<li><a href="#linkage">Linkage Types</a></li>
<li><a href="#callingconv">Calling Conventions</a></li>
<li><a href="#globalvars">Global Variables</a></li>
- <li><a href="#functionstructure">Function Structure</a></li>
+ <li><a href="#functionstructure">Functions</a></li>
+ <li><a href="#paramattrs">Parameter Attributes</a></li>
+ <li><a href="#moduleasm">Module-Level Inline Assembly</a></li>
</ol>
</li>
<li><a href="#typesystem">Type System</a>
<ol>
- <li><a href="#t_primitive">Primitive Types</a>
+ <li><a href="#t_primitive">Primitive Types</a>
<ol>
<li><a href="#t_classifications">Type Classifications</a></li>
</ol>
<li><a href="#t_function">Function Type</a></li>
<li><a href="#t_pointer">Pointer Type</a></li>
<li><a href="#t_struct">Structure Type</a></li>
+ <li><a href="#t_pstruct">Packed Structure Type</a></li>
<li><a href="#t_packed">Packed Type</a></li>
<li><a href="#t_opaque">Opaque Type</a></li>
</ol>
<li><a href="#constantexprs">Constant Expressions</a>
</ol>
</li>
+ <li><a href="#othervalues">Other Values</a>
+ <ol>
+ <li><a href="#inlineasm">Inline Assembler Expressions</a>
+ </ol>
+ </li>
<li><a href="#instref">Instruction Reference</a>
<ol>
<li><a href="#terminators">Terminator Instructions</a>
<li><a href="#i_add">'<tt>add</tt>' Instruction</a></li>
<li><a href="#i_sub">'<tt>sub</tt>' Instruction</a></li>
<li><a href="#i_mul">'<tt>mul</tt>' Instruction</a></li>
- <li><a href="#i_div">'<tt>div</tt>' Instruction</a></li>
- <li><a href="#i_rem">'<tt>rem</tt>' Instruction</a></li>
- <li><a href="#i_setcc">'<tt>set<i>cc</i></tt>' Instructions</a></li>
+ <li><a href="#i_udiv">'<tt>udiv</tt>' Instruction</a></li>
+ <li><a href="#i_sdiv">'<tt>sdiv</tt>' Instruction</a></li>
+ <li><a href="#i_fdiv">'<tt>fdiv</tt>' Instruction</a></li>
+ <li><a href="#i_urem">'<tt>urem</tt>' Instruction</a></li>
+ <li><a href="#i_srem">'<tt>srem</tt>' Instruction</a></li>
+ <li><a href="#i_frem">'<tt>frem</tt>' Instruction</a></li>
</ol>
</li>
<li><a href="#bitwiseops">Bitwise Binary Operations</a>
<li><a href="#i_or">'<tt>or</tt>' Instruction</a></li>
<li><a href="#i_xor">'<tt>xor</tt>' Instruction</a></li>
<li><a href="#i_shl">'<tt>shl</tt>' Instruction</a></li>
- <li><a href="#i_shr">'<tt>shr</tt>' Instruction</a></li>
+ <li><a href="#i_lshr">'<tt>lshr</tt>' Instruction</a></li>
+ <li><a href="#i_ashr">'<tt>ashr</tt>' Instruction</a></li>
+ </ol>
+ </li>
+ <li><a href="#vectorops">Vector Operations</a>
+ <ol>
+ <li><a href="#i_extractelement">'<tt>extractelement</tt>' Instruction</a></li>
+ <li><a href="#i_insertelement">'<tt>insertelement</tt>' Instruction</a></li>
+ <li><a href="#i_shufflevector">'<tt>shufflevector</tt>' Instruction</a></li>
</ol>
</li>
- <li><a href="#memoryops">Memory Access Operations</a>
+ <li><a href="#memoryops">Memory Access and Addressing Operations</a>
<ol>
<li><a href="#i_malloc">'<tt>malloc</tt>' Instruction</a></li>
<li><a href="#i_free">'<tt>free</tt>' Instruction</a></li>
<li><a href="#i_alloca">'<tt>alloca</tt>' Instruction</a></li>
- <li><a href="#i_load">'<tt>load</tt>' Instruction</a></li>
- <li><a href="#i_store">'<tt>store</tt>' Instruction</a></li>
- <li><a href="#i_getelementptr">'<tt>getelementptr</tt>' Instruction</a></li>
+
<li><a href="#i_load">'<tt>load</tt>' Instruction</a></li>
+
<li><a href="#i_store">'<tt>store</tt>' Instruction</a></li>
+
<li><a href="#i_getelementptr">'<tt>getelementptr</tt>' Instruction</a></li>
</ol>
</li>
+ <li><a href="#convertops">Conversion Operations</a>
+ <ol>
+ <li><a href="#i_trunc">'<tt>trunc .. to</tt>' Instruction</a></li>
+ <li><a href="#i_zext">'<tt>zext .. to</tt>' Instruction</a></li>
+ <li><a href="#i_sext">'<tt>sext .. to</tt>' Instruction</a></li>
+ <li><a href="#i_fptrunc">'<tt>fptrunc .. to</tt>' Instruction</a></li>
+ <li><a href="#i_fpext">'<tt>fpext .. to</tt>' Instruction</a></li>
+ <li><a href="#i_fptoui">'<tt>fptoui .. to</tt>' Instruction</a></li>
+ <li><a href="#i_fptosi">'<tt>fptosi .. to</tt>' Instruction</a></li>
+ <li><a href="#i_uitofp">'<tt>uitofp .. to</tt>' Instruction</a></li>
+ <li><a href="#i_sitofp">'<tt>sitofp .. to</tt>' Instruction</a></li>
+ <li><a href="#i_ptrtoint">'<tt>ptrtoint .. to</tt>' Instruction</a></li>
+ <li><a href="#i_inttoptr">'<tt>inttoptr .. to</tt>' Instruction</a></li>
+ <li><a href="#i_bitcast">'<tt>bitcast .. to</tt>' Instruction</a></li>
+ </ol>
<li><a href="#otherops">Other Operations</a>
<ol>
+ <li><a href="#i_icmp">'<tt>icmp</tt>' Instruction</a></li>
+ <li><a href="#i_fcmp">'<tt>fcmp</tt>' Instruction</a></li>
<li><a href="#i_phi">'<tt>phi</tt>' Instruction</a></li>
- <li><a href="#i_cast">'<tt>cast .. to</tt>' Instruction</a></li>
<li><a href="#i_select">'<tt>select</tt>' Instruction</a></li>
<li><a href="#i_call">'<tt>call</tt>' Instruction</a></li>
- <li><a href="#i_vanext">'<tt>vanext</tt>' Instruction</a></li>
- <li><a href="#i_vaarg">'<tt>vaarg</tt>' Instruction</a></li>
+ <li><a href="#i_va_arg">'<tt>va_arg</tt>' Instruction</a></li>
</ol>
</li>
</ol>
<ol>
<li><a href="#i_returnaddress">'<tt>llvm.returnaddress</tt>' Intrinsic</a></li>
<li><a href="#i_frameaddress">'<tt>llvm.frameaddress</tt>' Intrinsic</a></li>
+ <li><a href="#i_stacksave">'<tt>llvm.stacksave</tt>' Intrinsic</a></li>
+ <li><a href="#i_stackrestore">'<tt>llvm.stackrestore</tt>' Intrinsic</a></li>
<li><a href="#i_prefetch">'<tt>llvm.prefetch</tt>' Intrinsic</a></li>
<li><a href="#i_pcmarker">'<tt>llvm.pcmarker</tt>' Intrinsic</a></li>
+ <li><a href="#i_readcyclecounter"><tt>llvm.readcyclecounter</tt>' Intrinsic</a></li>
</ol>
</li>
- <li><a href="#int_os">Operating System Intrinsics</a>
- <ol>
- <li><a href="#i_readport">'<tt>llvm.readport</tt>' Intrinsic</a></li>
- <li><a href="#i_writeport">'<tt>llvm.writeport</tt>' Intrinsic</a></li>
- <li><a href="#i_readio">'<tt>llvm.readio</tt>' Intrinsic</a></li>
- <li><a href="#i_writeio">'<tt>llvm.writeio</tt>' Intrinsic</a></li>
- </ol>
<li><a href="#int_libc">Standard C Library Intrinsics</a>
<ol>
- <li><a href="#i_memcpy">'<tt>llvm.memcpy</tt>' Intrinsic</a></li>
- <li><a href="#i_memmove">'<tt>llvm.memmove</tt>' Intrinsic</a></li>
- <li><a href="#i_memset">'<tt>llvm.memset</tt>' Intrinsic</a></li>
- <li><a href="#i_isunordered">'<tt>llvm.isunordered</tt>' Intrinsic</a></li>
+ <li><a href="#i_memcpy">'<tt>llvm.memcpy.*</tt>' Intrinsic</a></li>
+ <li><a href="#i_memmove">'<tt>llvm.memmove.*</tt>' Intrinsic</a></li>
+ <li><a href="#i_memset">'<tt>llvm.memset.*</tt>' Intrinsic</a></li>
+ <li><a href="#i_isunordered">'<tt>llvm.isunordered.*</tt>' Intrinsic</a></li>
+ <li><a href="#i_sqrt">'<tt>llvm.sqrt.*</tt>' Intrinsic</a></li>
+ <li><a href="#i_powi">'<tt>llvm.powi.*</tt>' Intrinsic</a></li>
</ol>
</li>
- <li><a href="#int_count">Bit counting Intrinsics</a>
+ <li><a href="#int_manip">Bit Manipulation Intrinsics</a>
<ol>
- <li><a href="#int_ctpop">'<tt>llvm.ctpop</tt>' Intrinsic </a></li>
- <li><a href="#int_cttz">'<tt>llvm.cttz</tt>' Intrinsic </a></li>
- <li><a href="#int_ctlz">'<tt>llvm.ctlz</tt>' Intrinsic </a></li>
+ <li><a href="#i_bswap">'<tt>llvm.bswap.*</tt>' Intrinsics</a></li>
+ <li><a href="#int_ctpop">'<tt>llvm.ctpop.*</tt>' Intrinsic </a></li>
+ <li><a href="#int_ctlz">'<tt>llvm.ctlz.*</tt>' Intrinsic </a></li>
+ <li><a href="#int_cttz">'<tt>llvm.cttz.*</tt>' Intrinsic </a></li>
</ol>
</li>
<li><a href="#int_debugger">Debugger intrinsics</a></li>
of LLVM are all equivalent. This document describes the human readable
representation and notation.</p>
-<p>The LLVM representation aims to be a light-weight and low-level
+<p>The LLVM representation aims to be light-weight and low-level
while being expressive, typed, and extensible at the same time. It
aims to be a "universal IR" of sorts, by being at a low enough level
that high-level ideas may be cleanly mapped to it (similar to how
following instruction is syntactically okay, but not well formed:</p>
<pre>
- %x = <a href="#i_add">add</a> int 1, %x
+ %x = <a href="#i_add">add</a> i32 1, %x
</pre>
<p>...because the definition of <tt>%x</tt> does not dominate all of
its uses. The LLVM infrastructure provides a verification pass that may
be used to verify that an LLVM module is well formed. This pass is
-automatically run by the parser after parsing input assembly, and by
+automatically run by the parser after parsing input assembly and by
the optimizer before it outputs bytecode. The violations pointed out
by the verifier pass indicate bugs in transformation passes or input to
the parser.</p>
variable without having to avoid symbol table conflicts.</p>
<p>Reserved words in LLVM are very similar to reserved words in other
-languages. There are keywords for different opcodes ('<tt><a
-href="#i_add">add</a></tt>', '<tt><a href="#i_cast">cast</a></tt>', '<tt><a
-href="#i_ret">ret</a></tt>', etc...), for primitive type names ('<tt><a
-href="#t_void">void</a></tt>', '<tt><a href="#t_uint">uint</a></tt>', etc...),
+languages. There are keywords for different opcodes
+('<tt><a href="#i_add">add</a></tt>',
+ '<tt><a href="#i_bitcast">bitcast</a></tt>',
+ '<tt><a href="#i_ret">ret</a></tt>', etc...), for primitive type names ('<tt><a
+href="#t_void">void</a></tt>', '<tt><a href="#t_primitive">i32</a></tt>', etc...),
and others. These reserved words cannot conflict with variable names, because
none of them start with a '%' character.</p>
<p>The easy way:</p>
<pre>
- %result = <a href="#i_mul">mul</a> uint %X, 8
+ %result = <a href="#i_mul">mul</a> i32 %X, 8
</pre>
<p>After strength reduction:</p>
<pre>
- %result = <a href="#i_shl">shl</a> uint %X, ubyte 3
+ %result = <a href="#i_shl">shl</a> i32 %X, i8 3
</pre>
<p>And the hard way:</p>
<pre>
- <a href="#i_add">add</a> uint %X, %X <i>; yields {uint}:%0</i>
- <a href="#i_add">add</a> uint %0, %0 <i>; yields {uint}:%1</i>
- %result = <a href="#i_add">add</a> uint %1, %1
+ <a href="#i_add">add</a> i32 %X, %X <i>; yields {i32}:%0</i>
+ <a href="#i_add">add</a> i32 %0, %0 <i>; yields {i32}:%1</i>
+ %result = <a href="#i_add">add</a> i32 %1, %1
</pre>
<p>This last way of multiplying <tt>%X</tt> by 8 illustrates several
</ol>
-<p>...and it also show a convention that we follow in this document. When
+<p>...and it also shows a convention that we follow in this document. When
demonstrating instructions, we will follow an instruction with a comment that
defines the type and name of value produced. Comments are shown in italic
text.</p>
<pre><i>; Declare the string constant as a global constant...</i>
<a href="#identifiers">%.LC0</a> = <a href="#linkage_internal">internal</a> <a
- href="#globalvars">constant</a> <a href="#t_array">[13 x sbyte]</a> c"hello world\0A\00" <i>; [13 x sbyte]*</i>
+ href="#globalvars">constant</a> <a href="#t_array">[13 x i8 ]</a> c"hello world\0A\00" <i>; [13 x i8 ]*</i>
<i>; External declaration of the puts function</i>
-<a href="#functionstructure">declare</a> int %puts(sbyte*) <i>; int(sbyte*)* </i>
+<a href="#functionstructure">declare</a> i32 %puts(i8 *) <i>; i32(i8 *)* </i>
+
+<i>; Global variable / Function body section separator</i>
+implementation
<i>; Definition of main function</i>
-int %main() { <i>; int()* </i>
- <i>; Convert [13x sbyte]* to sbyte *...</i>
+define i32 %main() { <i>; i32()* </i>
+ <i>; Convert [13x i8 ]* to i8 *...</i>
%cast210 = <a
- href="#i_getelementptr">getelementptr</a> [13 x sbyte]* %.LC0, long 0, long 0 <i>; sbyte*</i>
+ href="#i_getelementptr">getelementptr</a> [13 x i8 ]* %.LC0, i64 0, i64 0 <i>; i8 *</i>
<i>; Call puts function to write out the string to stdout...</i>
<a
- href="#i_call">call</a> int %puts(sbyte* %cast210) <i>; int</i>
+ href="#i_call">call</a> i32 %puts(i8 * %cast210) <i>; i32</i>
<a
- href="#i_ret">ret</a> int 0<br>}<br></pre>
+ href="#i_ret">ret</a> i32 0<br>}<br></pre>
<p>This example is made up of a <a href="#globalvars">global variable</a>
named "<tt>.LC0</tt>", an external declaration of the "<tt>puts</tt>"
array of char, and a pointer to a function), and have one of the following <a
href="#linkage">linkage types</a>.</p>
+<p>Due to a limitation in the current LLVM assembly parser (it is limited by
+one-token lookahead), modules are split into two pieces by the "implementation"
+keyword. Global variable prototypes and definitions must occur before the
+keyword, and function definitions must occur after it. Function prototypes may
+occur either before or after it. In the future, the implementation keyword may
+become a noop, if the parser gets smarter.</p>
+
</div>
<!-- ======================================================================= -->
<dd>"<tt>weak</tt>" linkage is exactly the same as <tt>linkonce</tt> linkage,
except that unreferenced <tt>weak</tt> globals may not be discarded. This is
- used to implement constructs in C such as "<tt>int X;</tt>" at global scope.
+ used to implement constructs in C such as "<tt>i32 X;</tt>" at global scope.
</dd>
<dt><tt><b><a name="linkage_appending">appending</a></b></tt>: </dt>
visible, meaning that it participates in linkage and can be used to resolve
external symbol references.
</dd>
+
+ <dt><tt><b><a name="linkage_externweak">extern_weak</a></b></tt>: </dt>
+
+ <dd>"<tt>extern_weak</tt>" TBD
+ </dd>
+
+ <p>
+ The next two types of linkage are targeted for Microsoft Windows platform
+ only. They are designed to support importing (exporting) symbols from (to)
+ DLLs.
+ </p>
+
+ <dt><tt><b><a name="linkage_dllimport">dllimport</a></b></tt>: </dt>
+
+ <dd>"<tt>dllimport</tt>" linkage causes the compiler to reference a function
+ or variable via a global pointer to a pointer that is set up by the DLL
+ exporting the symbol. On Microsoft Windows targets, the pointer name is
+ formed by combining <code>_imp__</code> and the function or variable name.
+ </dd>
+
+ <dt><tt><b><a name="linkage_dllexport">dllexport</a></b></tt>: </dt>
+
+ <dd>"<tt>dllexport</tt>" linkage causes the compiler to provide a global
+ pointer to a pointer in a DLL, so that it can be referenced with the
+ <tt>dllimport</tt> attribute. On Microsoft Windows targets, the pointer
+ name is formed by combining <code>_imp__</code> and the function or variable
+ name.
+ </dd>
+
</dl>
<p><a name="linkage_external">For example, since the "<tt>.LC0</tt>"
<dd>This calling convention (the default if no other calling convention is
specified) matches the target C calling conventions. This calling convention
- supports varargs function calls, and tolerates some mismatch in the declared
- prototype and implemented declaration of the function (as does normal C).
+ supports varargs function calls and tolerates some mismatch in the declared
+ prototype and implemented declaration of the function (as does normal C).
+ </dd>
+
+ <dt><b>"<tt>csretcc</tt>" - The C struct return calling convention</b>:</dt>
+
+ <dd>This calling convention matches the target C calling conventions, except
+ that functions with this convention are required to take a pointer as their
+ first argument, and the return type of the function must be void. This is
+ used for C functions that return aggregates by-value. In this case, the
+ function has been transformed to take a pointer to the struct as the first
+ argument to the function. For targets where the ABI specifies specific
+ behavior for structure-return calls, the calling convention can be used to
+ distinguish between struct return functions and other functions that take a
+ pointer to a struct as the first argument.
</dd>
<dt><b>"<tt>fastcc</tt>" - The fast calling convention</b>:</dt>
<div class="doc_text">
<p>Global variables define regions of memory allocated at compilation time
-instead of run-time. Global variables may optionally be initialized. A
-variable may be defined as a global "constant", which indicates that the
+instead of run-time. Global variables may optionally be initialized, may have
+an explicit section to be placed in, and may
+have an optional explicit alignment specified. A
+variable may be defined as a global "constant," which indicates that the
contents of the variable will <b>never</b> be modified (enabling better
optimization, allowing the global data to be placed in the read-only section of
an executable, etc). Note that variables that need runtime initialization
-cannot be marked "constant", as there is a store to the variable.</p>
+cannot be marked "constant" as there is a store to the variable.</p>
<p>
LLVM explicitly allows <em>declarations</em> of global variables to be marked
describe a region of memory, and all memory objects in LLVM are
accessed through pointers.</p>
+<p>LLVM allows an explicit section to be specified for globals. If the target
+supports it, it will emit globals to the section specified.</p>
+
+<p>An explicit alignment may be specified for a global. If not present, or if
+the alignment is set to zero, the alignment of the global is set by the target
+to whatever it feels convenient. If an explicit alignment is specified, the
+global is forced to have at least that much alignment. All alignments must be
+a power of 2.</p>
+
</div>
<div class="doc_text">
-<p>LLVM function definitions consist of an optional <a href="#linkage">linkage
-type</a>, an optional <a href="#callingconv">calling convention</a>, a return
-type, a function name, a (possibly empty) argument list, an opening curly brace,
-a list of basic blocks, and a closing curly brace. LLVM function declarations
-are defined with the "<tt>declare</tt>" keyword, an optional <a
-href="#callingconv">calling convention</a>, a return type, a function name, and
-a possibly empty list of arguments.</p>
+<p>LLVM function definitions consist of the "<tt>define</tt>" keyord,
+an optional <a href="#linkage">linkage type</a>, an optional
+<a href="#callingconv">calling convention</a>, a return type, an optional
+<a href="#paramattrs">parameter attribute</a> for the return type, a function
+name, a (possibly empty) argument list (each with optional
+<a href="#paramattrs">parameter attributes</a>), an optional section, an
+optional alignment, an opening curly brace, a list of basic blocks, and a
+closing curly brace. LLVM function declarations
+consist of the "<tt>declare</tt>" keyword, an optional <a
+ href="#callingconv">calling convention</a>, a return type, an optional
+<a href="#paramattrs">parameter attribute</a> for the return type, a function
+name, a possibly empty list of arguments, and an optional alignment.</p>
<p>A function definition contains a list of basic blocks, forming the CFG for
the function. Each basic block may optionally start with a label (giving the
with a <a href="#terminators">terminator</a> instruction (such as a branch or
function return).</p>
-<p>The first basic block in program is special in two ways: it is immediately
+<p>The first basic block in a program is special in two ways: it is immediately
executed on entrance to the function, and it is not allowed to have predecessor
basic blocks (i.e. there can not be any branches to the entry block of a
function). Because the block can have no predecessors, it also cannot have any
considered different functions, and LLVM will resolve references to each
appropriately.</p>
+<p>LLVM allows an explicit section to be specified for functions. If the target
+supports it, it will emit functions to the section specified.</p>
+
+<p>An explicit alignment may be specified for a function. If not present, or if
+the alignment is set to zero, the alignment of the function is set by the target
+to whatever it feels convenient. If an explicit alignment is specified, the
+function is forced to have at least that much alignment. All alignments must be
+a power of 2.</p>
+
+</div>
+
+<!-- ======================================================================= -->
+<div class="doc_subsection"><a name="paramattrs">Parameter Attributes</a></div>
+<div class="doc_text">
+ <p>The return type and each parameter of a function type may have a set of
+ <i>parameter attributes</i> associated with them. Parameter attributes are
+ used to communicate additional information about the result or parameters of
+ a function. Parameter attributes are considered to be part of the function
+ type so two functions types that differ only by the parameter attributes
+ are different function types.</p>
+
+ <p>Parameter attributes consist of an at sign (@) followed by either a single
+ keyword or a comma separate list of keywords enclosed in parentheses. For
+ example:<pre>
+ %someFunc = i16 @zext (i8 @(sext) %someParam)
+ %someFunc = i16 @zext (i8 @zext %someParam)</pre>
+ Note that the two function types above are unique because the parameter
+ has a different attribute (@sext in the first one, @zext in the second).</p>
+
+ <p>Currently, only the following parameter attributes are defined:
+ <dl>
+ <dt><tt>@zext</tt></dt>
+ <dd>This indicates that the parameter should be zero extended just before
+ a call to this function.</dd>
+ <dt><tt>@sext</tt></dt>
+ <dd>This indicates that the parameter should be sign extended just before
+ a call to this function.</dd>
+ </dl></p>
+
+ <p>The current motivation for parameter attributes is to enable the sign and
+ zero extend information necessary for the C calling convention to be passed
+ from the front end to LLVM. The <tt>@zext</tt> and <tt>@sext</tt> attributes
+ are used by the code generator to perform the required extension. However,
+ parameter attributes are an orthogonal feature to calling conventions and
+ may be used for other purposes in the future.</p>
+</div>
+
+<!-- ======================================================================= -->
+<div class="doc_subsection">
+ <a name="moduleasm">Module-Level Inline Assembly</a>
</div>
+<div class="doc_text">
+<p>
+Modules may contain "module-level inline asm" blocks, which corresponds to the
+GCC "file scope inline asm" blocks. These blocks are internally concatenated by
+LLVM and treated as a single unit, but may be separated in the .ll file if
+desired. The syntax is very simple:
+</p>
+
+<div class="doc_code"><pre>
+ module asm "inline asm code goes here"
+ module asm "more can go here"
+</pre></div>
+
+<p>The strings can contain any character by escaping non-printable characters.
+ The escape sequence used is simply "\xx" where "xx" is the two digit hex code
+ for the number.
+</p>
+
+<p>
+ The inline asm code is simply printed to the machine code .s file when
+ assembly code is generated.
+</p>
+</div>
<!-- *********************************************************************** -->
<tbody>
<tr><th>Type</th><th>Description</th></tr>
<tr><td><tt>void</tt></td><td>No value</td></tr>
- <tr><td><tt>ubyte</tt></td><td>Unsigned 8-bit value</td></tr>
- <tr><td><tt>ushort</tt></td><td>Unsigned 16-bit value</td></tr>
- <tr><td><tt>uint</tt></td><td>Unsigned 32-bit value</td></tr>
- <tr><td><tt>ulong</tt></td><td>Unsigned 64-bit value</td></tr>
+ <tr><td><tt>i8</tt></td><td>Signless 8-bit value</td></tr>
+ <tr><td><tt>i32</tt></td><td>Signless 32-bit value</td></tr>
<tr><td><tt>float</tt></td><td>32-bit floating point value</td></tr>
<tr><td><tt>label</tt></td><td>Branch destination</td></tr>
</tbody>
<tbody>
<tr><th>Type</th><th>Description</th></tr>
<tr><td><tt>bool</tt></td><td>True or False value</td></tr>
- <tr><td><tt>sbyte</tt></td><td>Signed 8-bit value</td></tr>
- <tr><td><tt>short</tt></td><td>Signed 16-bit value</td></tr>
- <tr><td><tt>int</tt></td><td>Signed 32-bit value</td></tr>
- <tr><td><tt>long</tt></td><td>Signed 64-bit value</td></tr>
- <tr><td><tt>double</tt></td><td>64-bit floating point value</td></tr>
+ <tr><td><tt>i16</tt></td><td>Signless 16-bit value</td></tr>
+ <tr><td><tt>i64</tt></td><td>Signless 64-bit value</td></tr>
+ <tr><td><tt>double</tt></td><td>64-bit floating point value</td></tr>
</tbody>
</table>
</td>
<table border="1" cellspacing="0" cellpadding="4">
<tbody>
<tr><th>Classification</th><th>Types</th></tr>
- <tr>
- <td><a name="t_signed">signed</a></td>
- <td><tt>sbyte, short, int, long, float, double</tt></td>
- </tr>
- <tr>
- <td><a name="t_unsigned">unsigned</a></td>
- <td><tt>ubyte, ushort, uint, ulong</tt></td>
- </tr>
<tr>
<td><a name="t_integer">integer</a></td>
- <td><tt>ubyte, sbyte, ushort, short, uint, int, ulong, long</tt></td>
+ <td><tt>i8, i16, i32, i64</tt></td>
</tr>
<tr>
<td><a name="t_integral">integral</a></td>
- <td><tt>bool, ubyte, sbyte, ushort, short, uint, int, ulong, long</tt>
+ <td><tt>bool, i8, i16, i32, i64</tt>
</td>
</tr>
<tr>
</tr>
<tr>
<td><a name="t_firstclass">first class</a></td>
- <td><tt>bool, ubyte, sbyte, ushort, short, uint, int, ulong, long,<br>
- float, double, <a href="#t_pointer">pointer</a>,
- <a href="#t_packed">packed</a></tt></td>
+ <td><tt>bool, i8, i16, i32, i64, float, double, <br/>
+ <a href="#t_pointer">pointer</a>,<a href="#t_packed">packed</a></tt>
+ </td>
</tr>
</tbody>
</table>
[<# elements> x <elementtype>]
</pre>
-<p>The number of elements is a constant integer value, elementtype may
+<p>The number of elements is a constant integer value; elementtype may
be any type with a size.</p>
<h5>Examples:</h5>
<table class="layout">
<tr class="layout">
<td class="left">
- <tt>[40 x int ]</tt><br/>
- <tt>[41 x int ]</tt><br/>
- <tt>[40 x uint]</tt><br/>
+ <tt>[40 x i32 ]</tt><br/>
+ <tt>[41 x i32 ]</tt><br/>
+ <tt>[40 x i8]</tt><br/>
</td>
<td class="left">
- Array of 40 integer values.<br/>
- Array of 41 integer values.<br/>
- Array of 40 unsigned integer values.<br/>
+ Array of 40 32-bit integer values.<br/>
+ Array of 41 32-bit integer values.<br/>
+ Array of 40 8-bit integer values.<br/>
</td>
</tr>
</table>
<table class="layout">
<tr class="layout">
<td class="left">
- <tt>[3 x [4 x int]]</tt><br/>
+ <tt>[3 x [4 x i32]]</tt><br/>
<tt>[12 x [10 x float]]</tt><br/>
- <tt>[2 x [3 x [4 x uint]]]</tt><br/>
+ <tt>[2 x [3 x [4 x i16]]]</tt><br/>
</td>
<td class="left">
- 3x4 array integer values.<br/>
+ 3x4 array of 32-bit integer values.<br/>
12x10 array of single precision floating point values.<br/>
- 2x3x4 array of unsigned integer values.<br/>
+ 2x3x4 array of 16-bit integer values.<br/>
</td>
</tr>
</table>
+
+<p>Note that 'variable sized arrays' can be implemented in LLVM with a zero
+length array. Normally, accesses past the end of an array are undefined in
+LLVM (e.g. it is illegal to access the 5th element of a 3 element array).
+As a special case, however, zero length arrays are recognized to be variable
+length. This allows implementation of 'pascal style arrays' with the LLVM
+type "{ i32, [0 x float]}", for example.</p>
+
</div>
<!-- _______________________________________________________________________ -->
</p>
<h5>Syntax:</h5>
<pre> <returntype> (<parameter list>)<br></pre>
-<p>Where '<tt><parameter list></tt>' is a comma-separated list of type
+<p>...where '<tt><parameter list></tt>' is a comma-separated list of type
specifiers. Optionally, the parameter list may include a type <tt>...</tt>,
which indicates that the function takes a variable number of arguments.
Variable argument functions can access their arguments with the <a
<h5>Examples:</h5>
<table class="layout">
<tr class="layout">
- <td class="left">
- <tt>int (int)</tt> <br/>
- <tt>float (int, int *) *</tt><br/>
- <tt>int (sbyte *, ...)</tt><br/>
+ <td class="left"><tt>i32 (i32)</tt></td>
+ <td class="left">function taking an <tt>i32</tt>, returning an <tt>i32</tt>
</td>
- <td class="left">
- function taking an <tt>int</tt>, returning an <tt>int</tt><br/>
- <a href="#t_pointer">Pointer</a> to a function that takes an
- <tt>int</tt> and a <a href="#t_pointer">pointer</a> to <tt>int</tt>,
- returning <tt>float</tt>.<br/>
- A vararg function that takes at least one <a href="#t_pointer">pointer</a>
- to <tt>sbyte</tt> (signed char in C), which returns an integer. This is
- the signature for <tt>printf</tt> in LLVM.<br/>
+ </tr><tr class="layout">
+ <td class="left"><tt>float (i16 @sext, i32 *) *
+ </tt></td>
+ <td class="left"><a href="#t_pointer">Pointer</a> to a function that takes
+ an <tt>i16</tt> that should be sign extended and a
+ <a href="#t_pointer">pointer</a> to <tt>i32</tt>, returning
+ <tt>float</tt>.
+ </td>
+ </tr><tr class="layout">
+ <td class="left"><tt>i32 (i8*, ...)</tt></td>
+ <td class="left">A vararg function that takes at least one
+ <a href="#t_pointer">pointer</a> to <tt>i8 </tt> (char in C),
+ which returns an integer. This is the signature for <tt>printf</tt> in
+ LLVM.
</td>
</tr>
</table>
<table class="layout">
<tr class="layout">
<td class="left">
- <tt>{ int, int, int }</tt><br/>
- <tt>{ float, int (int) * }</tt><br/>
+ <tt>{ i32, i32, i32 }</tt><br/>
+ <tt>{ float, i32 (i32) * }</tt><br/>
+ </td>
+ <td class="left">
+ a triple of three <tt>i32</tt> values<br/>
+ A pair, where the first element is a <tt>float</tt> and the second element
+ is a <a href="#t_pointer">pointer</a> to a <a href="#t_function">function</a>
+ that takes an <tt>i32</tt>, returning an <tt>i32</tt>.<br/>
+ </td>
+ </tr>
+</table>
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection"> <a name="t_pstruct">Packed Structure Type</a>
+</div>
+<div class="doc_text">
+<h5>Overview:</h5>
+<p>The packed structure type is used to represent a collection of data members
+together in memory. There is no padding between fields. Further, the alignment
+of a packed structure is 1 byte. The elements of a packed structure may
+be any type that has a size.</p>
+<p>Structures are accessed using '<tt><a href="#i_load">load</a></tt>
+and '<tt><a href="#i_store">store</a></tt>' by getting a pointer to a
+field with the '<tt><a href="#i_getelementptr">getelementptr</a></tt>'
+instruction.</p>
+<h5>Syntax:</h5>
+<pre> < { <type list> } > <br></pre>
+<h5>Examples:</h5>
+<table class="layout">
+ <tr class="layout">
+ <td class="left">
+ <tt> < { i32, i32, i32 } > </tt><br/>
+ <tt> < { float, i32 (i32) * } > </tt><br/>
</td>
<td class="left">
- a triple of three <tt>int</tt> values<br/>
+ a triple of three <tt>i32</tt> values<br/>
A pair, where the first element is a <tt>float</tt> and the second element
is a <a href="#t_pointer">pointer</a> to a <a href="#t_function">function</a>
- that takes an <tt>int</tt>, returning an <tt>int</tt>.<br/>
+ that takes an <tt>i32</tt>, returning an <tt>i32</tt>.<br/>
</td>
</tr>
</table>
<table class="layout">
<tr class="layout">
<td class="left">
- <tt>[4x int]*</tt><br/>
- <tt>int (int *) *</tt><br/>
+ <tt>[4x i32]*</tt><br/>
+ <tt>i32 (i32 *) *</tt><br/>
</td>
<td class="left">
A <a href="#t_pointer">pointer</a> to <a href="#t_array">array</a> of
- four <tt>int</tt> values<br/>
+ four <tt>i32</tt> values<br/>
A <a href="#t_pointer">pointer</a> to a <a
- href="#t_function">function</a> that takes an <tt>int*</tt>, returning an
- <tt>int</tt>.<br/>
+ href="#t_function">function</a> that takes an <tt>i32*</tt>, returning an
+ <tt>i32</tt>.<br/>
</td>
</tr>
</table>
of elements. Packed types are used when multiple primitive data
are operated in parallel using a single instruction (SIMD).
A packed type requires a size (number of
-elements) and an underlying primitive data type. Packed types are
+elements) and an underlying primitive data type. Vectors must have a power
+of two length (1, 2, 4, 8, 16 ...). Packed types are
considered <a href="#t_firstclass">first class</a>.</p>
<h5>Syntax:</h5>
< <# elements> x <elementtype> >
</pre>
-<p>The number of elements is a constant integer value, elementtype may
+<p>The number of elements is a constant integer value; elementtype may
be any integral or floating point type.</p>
<h5>Examples:</h5>
<table class="layout">
<tr class="layout">
<td class="left">
- <tt><4 x int></tt><br/>
+ <tt><4 x i32></tt><br/>
<tt><8 x float></tt><br/>
- <tt><2 x uint></tt><br/>
+ <tt><2 x i64></tt><br/>
</td>
<td class="left">
- Packed vector of 4 integer values.<br/>
+ Packed vector of 4 32-bit integer values.<br/>
Packed vector of 8 floating-point values.<br/>
- Packed vector of 2 unsigned integer values.<br/>
+ Packed vector of 2 64-bit integer values.<br/>
</td>
</tr>
</table>
<dt><b>Integer constants</b></dt>
<dd>Standard integers (such as '4') are constants of the <a
- href="#t_integer">integer</a> type. Negative numbers may be used with signed
+ href="#t_integer">integer</a> type. Negative numbers may be used with
integer types.
</dd>
<dd>Floating point constants use standard decimal notation (e.g. 123.421),
exponential notation (e.g. 1.23421e+2), or a more precise hexadecimal
- notation. Floating point constants have an optional hexadecimal
notation (see below). Floating point constants must have a <a
href="#t_floating">floating point</a> type. </dd>
<dd>Structure constants are represented with notation similar to structure
type definitions (a comma separated list of elements, surrounded by braces
- (<tt>{}</tt>)). For example: "<tt>{ int 4, float 17.0, int* %G }</tt>",
- where "<tt>%G</tt>" is declared as "<tt>%G = external global int</tt>". Structure constants
+ (<tt>{}</tt>)). For example: "<tt>{ i32 4, float 17.0, i32* %G }</tt>",
+ where "<tt>%G</tt>" is declared as "<tt>%G = external global i32</tt>". Structure constants
must have <a href="#t_struct">structure type</a>, and the number and
types of elements must match those specified by the type.
</dd>
<dd>Array constants are represented with notation similar to array type
definitions (a comma separated list of elements, surrounded by square brackets
- (<tt>[]</tt>)). For example: "<tt>[ int 42, int 11, int 74 ]</tt>". Array
+ (<tt>[]</tt>)). For example: "<tt>[ i32 42, i32 11, i32 74 ]</tt>". Array
constants must have <a href="#t_array">array type</a>, and the number and
types of elements must match those specified by the type.
</dd>
<dd>Packed constants are represented with notation similar to packed type
definitions (a comma separated list of elements, surrounded by
- less-than/greater-than's (<tt><></tt>)). For example: "<tt>< int 42,
- i
nt 11, int 74, int 100 ></tt>". Packed constants must have <a
+ less-than/greater-than's (<tt><></tt>)). For example: "<tt>< i32 42,
+ i
32 11, i32 74, i32 100 ></tt>". Packed constants must have <a
href="#t_packed">packed type</a>, and the number and types of elements must
match those specified by the type.
</dd>
<dd>The string '<tt>zeroinitializer</tt>' can be used to zero initialize a
value to zero of <em>any</em> type, including scalar and aggregate types.
This is often used to avoid having to print large zero initializers (e.g. for
- large arrays), and is always exactly equivalent to using explicit zero
+ large arrays) and is always exactly equivalent to using explicit zero
initializers.
</dd>
</dl>
file:</p>
<pre>
- %X = global int 17
- %Y = global int 42
- %Z = global [2 x int*] [ int* %X, int* %Y ]
+ %X = global i32 17
+ %Y = global i32 42
+ %Z = global [2 x i32*] [ i32* %X, i32* %Y ]
</pre>
</div>
<div class="doc_subsection"><a name="undefvalues">Undefined Values</a></div>
<div class="doc_text">
<p>The string '<tt>undef</tt>' is recognized as a type-less constant that has
- no specific value. Undefined values may be of any type, and be used anywhere
+ no specific value. Undefined values may be of any type and be used anywhere
a constant is permitted.</p>
<p>Undefined values indicate to the compiler that the program is well defined
<p>Constant expressions are used to allow expressions involving other constants
to be used as constants. Constant expressions may be of any <a
-href="#t_firstclass">first class</a> type, and may involve any LLVM operation
+href="#t_firstclass">first class</a> type and may involve any LLVM operation
that does not have side effects (e.g. load and call are not supported). The
following is the syntax for constant expressions:</p>
<dl>
- <dt><b><tt>cast ( CST to TYPE )</tt></b></dt>
-
- <dd>Cast a constant to another type.</dd>
+ <dt><b><tt>trunc ( CST to TYPE )</tt></b></dt>
+ <dd>Truncate a constant to another type. The bit size of CST must be larger
+ than the bit size of TYPE. Both types must be integral.</dd>
+
+ <dt><b><tt>zext ( CST to TYPE )</tt></b></dt>
+ <dd>Zero extend a constant to another type. The bit size of CST must be
+ smaller or equal to the bit size of TYPE. Both types must be integral.</dd>
+
+ <dt><b><tt>sext ( CST to TYPE )</tt></b></dt>
+ <dd>Sign extend a constant to another type. The bit size of CST must be
+ smaller or equal to the bit size of TYPE. Both types must be integral.</dd>
+
+ <dt><b><tt>fptrunc ( CST to TYPE )</tt></b></dt>
+ <dd>Truncate a floating point constant to another floating point type. The
+ size of CST must be larger than the size of TYPE. Both types must be
+ floating point.</dd>
+
+ <dt><b><tt>fpext ( CST to TYPE )</tt></b></dt>
+ <dd>Floating point extend a constant to another type. The size of CST must be
+ smaller or equal to the size of TYPE. Both types must be floating point.</dd>
+
+ <dt><b><tt>fp2uint ( CST to TYPE )</tt></b></dt>
+ <dd>Convert a floating point constant to the corresponding unsigned integer
+ constant. TYPE must be an integer type. CST must be floating point. If the
+ value won't fit in the integer type, the results are undefined.</dd>
+
+ <dt><b><tt>fptosi ( CST to TYPE )</tt></b></dt>
+ <dd>Convert a floating point constant to the corresponding signed integer
+ constant. TYPE must be an integer type. CST must be floating point. If the
+ value won't fit in the integer type, the results are undefined.</dd>
+
+ <dt><b><tt>uitofp ( CST to TYPE )</tt></b></dt>
+ <dd>Convert an unsigned integer constant to the corresponding floating point
+ constant. TYPE must be floating point. CST must be of integer type. If the
+ value won't fit in the floating point type, the results are undefined.</dd>
+
+ <dt><b><tt>sitofp ( CST to TYPE )</tt></b></dt>
+ <dd>Convert a signed integer constant to the corresponding floating point
+ constant. TYPE must be floating point. CST must be of integer type. If the
+ value won't fit in the floating point type, the results are undefined.</dd>
+
+ <dt><b><tt>ptrtoint ( CST to TYPE )</tt></b></dt>
+ <dd>Convert a pointer typed constant to the corresponding integer constant
+ TYPE must be an integer type. CST must be of pointer type. The CST value is
+ zero extended, truncated, or unchanged to make it fit in TYPE.</dd>
+
+ <dt><b><tt>inttoptr ( CST to TYPE )</tt></b></dt>
+ <dd>Convert a integer constant to a pointer constant. TYPE must be a
+ pointer type. CST must be of integer type. The CST value is zero extended,
+ truncated, or unchanged to make it fit in a pointer size. This one is
+ <i>really</i> dangerous!</dd>
+
+ <dt><b><tt>bitcast ( CST to TYPE )</tt></b></dt>
+ <dd>Convert a constant, CST, to another TYPE. The size of CST and TYPE must be
+ identical (same number of bits). The conversion is done as if the CST value
+ was stored to memory and read back as TYPE. In other words, no bits change
+ with this operator, just the type. This can be used for conversion of
+ packed types to any other type, as long as they have the same bit width. For
+ pointers it is only valid to cast to another pointer type.
+ </dd>
<dt><b><tt>getelementptr ( CSTPTR, IDX0, IDX1, ... )</tt></b></dt>
instruction, the index list may have zero or more indexes, which are required
to make sense for the type of "CSTPTR".</dd>
+ <dt><b><tt>select ( COND, VAL1, VAL2 )</tt></b></dt>
+
+ <dd>Perform the <a href="#i_select">select operation</a> on
+ constants.</dd>
+
+ <dt><b><tt>icmp COND ( VAL1, VAL2 )</tt></b></dt>
+ <dd>Performs the <a href="#i_icmp">icmp operation</a> on constants.</dd>
+
+ <dt><b><tt>fcmp COND ( VAL1, VAL2 )</tt></b></dt>
+ <dd>Performs the <a href="#i_fcmp">fcmp operation</a> on constants.</dd>
+
+ <dt><b><tt>extractelement ( VAL, IDX )</tt></b></dt>
+
+ <dd>Perform the <a href="#i_extractelement">extractelement
+ operation</a> on constants.
+
+ <dt><b><tt>insertelement ( VAL, ELT, IDX )</tt></b></dt>
+
+ <dd>Perform the <a href="#i_insertelement">insertelement
+ operation</a> on constants.</dd>
+
+
+ <dt><b><tt>shufflevector ( VEC1, VEC2, IDXMASK )</tt></b></dt>
+
+ <dd>Perform the <a href="#i_shufflevector">shufflevector
+ operation</a> on constants.</dd>
+
<dt><b><tt>OPCODE ( LHS, RHS )</tt></b></dt>
<dd>Perform the specified operation of the LHS and RHS constants. OPCODE may
be any of the <a href="#binaryops">binary</a> or <a href="#bitwiseops">bitwise
binary</a> operations. The constraints on operands are the same as those for
the corresponding instruction (e.g. no bitwise operations on floating point
- are allowed).</dd>
+ values are allowed).</dd>
</dl>
</div>
+<!-- *********************************************************************** -->
+<div class="doc_section"> <a name="othervalues">Other Values</a> </div>
+<!-- *********************************************************************** -->
+
+<!-- ======================================================================= -->
+<div class="doc_subsection">
+<a name="inlineasm">Inline Assembler Expressions</a>
+</div>
+
+<div class="doc_text">
+
+<p>
+LLVM supports inline assembler expressions (as opposed to <a href="#moduleasm">
+Module-Level Inline Assembly</a>) through the use of a special value. This
+value represents the inline assembler as a string (containing the instructions
+to emit), a list of operand constraints (stored as a string), and a flag that
+indicates whether or not the inline asm expression has side effects. An example
+inline assembler expression is:
+</p>
+
+<pre>
+ i32 (i32) asm "bswap $0", "=r,r"
+</pre>
+
+<p>
+Inline assembler expressions may <b>only</b> be used as the callee operand of
+a <a href="#i_call"><tt>call</tt> instruction</a>. Thus, typically we have:
+</p>
+
+<pre>
+ %X = call i32 asm "<a href="#i_bswap">bswap</a> $0", "=r,r"(i32 %Y)
+</pre>
+
+<p>
+Inline asms with side effects not visible in the constraint list must be marked
+as having side effects. This is done through the use of the
+'<tt>sideeffect</tt>' keyword, like so:
+</p>
+
+<pre>
+ call void asm sideeffect "eieio", ""()
+</pre>
+
+<p>TODO: The format of the asm and constraints string still need to be
+documented here. Constraints on what can be done (e.g. duplication, moving, etc
+need to be documented).
+</p>
+
+</div>
+
<!-- *********************************************************************** -->
<div class="doc_section"> <a name="instref">Instruction Reference</a> </div>
<!-- *********************************************************************** -->
<p>The LLVM instruction set consists of several different
classifications of instructions: <a href="#terminators">terminator
-instructions</a>, <a href="#binaryops">binary instructions</a>, <a
+instructions</a>, <a href="#binaryops">binary instructions</a>,
+<a href="#bitwiseops">bitwise binary instructions</a>, <a
href="#memoryops">memory instructions</a>, and <a href="#otherops">other
instructions</a>.</p>
</pre>
<h5>Overview:</h5>
<p>The '<tt>ret</tt>' instruction is used to return control flow (and a
-value) from a function, back to the caller.</p>
+value) from a function back to the caller.</p>
<p>There are two forms of the '<tt>ret</tt>' instruction: one that
returns a value and then causes control flow, and one that just causes
control flow to occur.</p>
href="#i_call"><tt>call</tt></a>" instruction, execution continues at
the instruction after the call. If the caller was an "<a
href="#i_invoke"><tt>invoke</tt></a>" instruction, execution continues
-at the beginning "normal" of the destination block. If the instruction
+at the beginning of the "normal" destination block. If the instruction
returns a value, that value shall set the call or invoke instruction's
return value.</p>
<h5>Example:</h5>
-<pre> ret int 5 <i>; Return an integer value of 5</i>
+<pre> ret i32 5 <i>; Return an integer value of 5</i>
ret void <i>; Return from a void function</i>
</pre>
</div>
to the '<tt>iftrue</tt>' <tt>label</tt> argument. If "cond" is <tt>false</tt>,
control flows to the '<tt>iffalse</tt>' <tt>label</tt> argument.</p>
<h5>Example:</h5>
-<pre>Test:<br> %cond = <a href="#i_
setcc">seteq</a> int %a, %b<br> br bool %cond, label %IfEqual, label %IfUnequal<br>IfEqual:<br> <a
- href="#i_ret">ret</a> int 1<br>IfUnequal:<br> <a href="#i_ret">ret</a> int 0<br></pre>
+<pre>Test:<br> %cond = <a href="#i_
icmp">icmp</a> eq, i32 %a, %b<br> br bool %cond, label %IfEqual, label %IfUnequal<br>IfEqual:<br> <a
+ href="#i_ret">ret</a> i32 1<br>IfUnequal:<br> <a href="#i_ret">ret</a> i32 0<br></pre>
</div>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
<pre>
<i>; Emulate a conditional br instruction</i>
- %Val = <a href="#i_cast">cast</a> bool %value to int
- switch int %Val, label %truedest [int 0, label %falsedest ]
+ %Val = <a href="#i_zext">zext</a> bool %value to i32
+ switch i32 %Val, label %truedest [i32 0, label %falsedest ]
<i>; Emulate an unconditional br instruction</i>
- switch uint 0, label %dest [ ]
+ switch i32 0, label %dest [ ]
<i>; Implement a jump table:</i>
- switch uint %val, label %otherwise [ uint 0, label %onzero
- uint 1, label %onone
- uint 2, label %ontwo ]
+ switch i32 %val, label %otherwise [ i32 0, label %onzero
+ i32 1, label %onone
+ i32 2, label %ontwo ]
</pre>
</div>
<pre>
<result> = invoke [<a href="#callingconv">cconv</a>] <ptr to function ty> %<function ptr val>(<function args>)
- to label <normal label> except label <exception label>
+ to label <normal label> unwind label <exception label>
</pre>
<h5>Overview:</h5>
<p>The '<tt>invoke</tt>' instruction causes control to transfer to a specified
function, with the possibility of control flow transfer to either the
-'<tt>normal</tt>' <tt>label</tt> label or the
-'<tt>exception</tt>'<tt>label</tt>. If the callee function returns with the
+'<tt>normal</tt>' label or the
+'<tt>exception</tt>' label. If the callee function returns with the
"<tt><a href="#i_ret">ret</a></tt>" instruction, control flow will return to the
"normal" label. If the callee (or any indirect callees) returns with the "<a
-href="#i_unwind"><tt>unwind</tt></a>" instruction, control is interrupted, and
-continued at the dynamically nearest "except" label.</p>
+href="#i_unwind"><tt>unwind</tt></a>" instruction, control is interrupted and
+continued at the dynamically nearest "exception" label.</p>
<h5>Arguments:</h5>
<ol>
<li>
-
<p>The optional "cconv" marker indicates which <a href="callingconv">calling
+ The optional "cconv" marker indicates which <a href="callingconv">calling
convention</a> the call should use. If none is specified, the call defaults
to using C calling conventions.
</li>
<h5>Example:</h5>
<pre>
- %retval = invoke int %Test(int 15) to label %Continue
- except label %TestCleanup <i>; {int}:retval set</i>
- %retval = invoke <a href="#callingconv">coldcc</a> int %Test(int 15) to label %Continue
- except label %TestCleanup <i>; {int}:retval set</i>
+ %retval = invoke i32 %Test(i32 15) to label %Continue
+ unwind label %TestCleanup <i>; {i32}:retval set</i>
+ %retval = invoke <a href="#callingconv">coldcc</a> i32 %Test(i32 15) to label %Continue
+ unwind label %TestCleanup <i>; {i32}:retval set</i>
</pre>
</div>
<p>The value produced is the integer or floating point sum of the two
operands.</p>
<h5>Example:</h5>
-<pre> <result> = add int 4, %var <i>; yields {int}:result = 4 + %var</i>
+<pre> <result> = add i32 4, %var <i>; yields {i32}:result = 4 + %var</i>
</pre>
</div>
<!-- _______________________________________________________________________ -->
<p>The value produced is the integer or floating point difference of
the two operands.</p>
<h5>Example:</h5>
-<pre> <result> = sub int 4, %var <i>; yields {int}:result = 4 - %var</i>
- <result> = sub int 0, %val <i>; yields {int}:result = -%var</i>
+<pre> <result> = sub i32 4, %var <i>; yields {i32}:result = 4 - %var</i>
+ <result> = sub i32 0, %val <i>; yields {i32}:result = -%var</i>
</pre>
</div>
<!-- _______________________________________________________________________ -->
<h5>Semantics:</h5>
<p>The value produced is the integer or floating point product of the
two operands.</p>
-<p>There is no signed vs unsigned multiplication. The appropriate
-action is taken based on the type of the operand.</p>
+<p>Because the operands are the same width, the result of an integer
+multiplication is the same whether the operands should be deemed unsigned or
+signed.</p>
+<h5>Example:</h5>
+<pre> <result> = mul i32 4, %var <i>; yields {i32}:result = 4 * %var</i>
+</pre>
+</div>
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection"> <a name="i_udiv">'<tt>udiv</tt>' Instruction
+</a></div>
+<div class="doc_text">
+<h5>Syntax:</h5>
+<pre> <result> = udiv <ty> <var1>, <var2> <i>; yields {ty}:result</i>
+</pre>
+<h5>Overview:</h5>
+<p>The '<tt>udiv</tt>' instruction returns the quotient of its two
+operands.</p>
+<h5>Arguments:</h5>
+<p>The two arguments to the '<tt>udiv</tt>' instruction must be
+<a href="#t_integer">integer</a> values. Both arguments must have identical
+types. This instruction can also take <a href="#t_packed">packed</a> versions
+of the values in which case the elements must be integers.</p>
+<h5>Semantics:</h5>
+<p>The value produced is the unsigned integer quotient of the two operands. This
+instruction always performs an unsigned division operation, regardless of
+whether the arguments are unsigned or not.</p>
+<h5>Example:</h5>
+<pre> <result> = udiv i32 4, %var <i>; yields {i32}:result = 4 / %var</i>
+</pre>
+</div>
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection"> <a name="i_sdiv">'<tt>sdiv</tt>' Instruction
+</a> </div>
+<div class="doc_text">
+<h5>Syntax:</h5>
+<pre> <result> = sdiv <ty> <var1>, <var2> <i>; yields {ty}:result</i>
+</pre>
+<h5>Overview:</h5>
+<p>The '<tt>sdiv</tt>' instruction returns the quotient of its two
+operands.</p>
+<h5>Arguments:</h5>
+<p>The two arguments to the '<tt>sdiv</tt>' instruction must be
+<a href="#t_integer">integer</a> values. Both arguments must have identical
+types. This instruction can also take <a href="#t_packed">packed</a> versions
+of the values in which case the elements must be integers.</p>
+<h5>Semantics:</h5>
+<p>The value produced is the signed integer quotient of the two operands. This
+instruction always performs a signed division operation, regardless of whether
+the arguments are signed or not.</p>
<h5>Example:</h5>
-<pre> <result> = mul int 4, %var <i>; yields {int}:result = 4 * %var</i>
+<pre> <result> = sdiv i32 4, %var <i>; yields {i32}:result = 4 / %var</i>
</pre>
</div>
<!-- _______________________________________________________________________ -->
-<div class="doc_subsubsection"> <a name="i_div">'<tt>div</tt>'
+<div class="doc_subsubsection"> <a name="i_fdiv">'<tt>fdiv</tt>'
Instruction</a> </div>
<div class="doc_text">
<h5>Syntax:</h5>
-<pre> <result> = div <ty> <var1>, <var2> <i>; yields {ty}:result</i>
+<pre> <result> = fdiv <ty> <var1>, <var2> <i>; yields {ty}:result</i>
</pre>
<h5>Overview:</h5>
-<p>The '<tt>div</tt>' instruction returns the quotient of its two
+<p>The '<tt>fdiv</tt>' instruction returns the quotient of its two
operands.</p>
<h5>Arguments:</h5>
-<p>The two arguments to the '<tt>div</tt>' instruction must be either <a
- href="#t_integer">integer</a> or <a href="#t_floating">floating point</a>
-values.
-This instruction can also take <a href="#t_packed">packed</a> versions of the values.
-Both arguments must have identical types.</p>
+<p>The two arguments to the '<tt>div</tt>' instruction must be
+<a href="#t_floating">floating point</a> values. Both arguments must have
+identical types. This instruction can also take <a href="#t_packed">packed</a>
+versions of the values in which case the elements must be floating point.</p>
<h5>Semantics:</h5>
-<p>The value produced is the integer or floating point quotient of the
-two operands.</p>
+<p>The value produced is the floating point quotient of the two operands.</p>
+<h5>Example:</h5>
+<pre> <result> = fdiv float 4.0, %var <i>; yields {float}:result = 4.0 / %var</i>
+</pre>
+</div>
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection"> <a name="i_urem">'<tt>urem</tt>' Instruction</a>
+</div>
+<div class="doc_text">
+<h5>Syntax:</h5>
+<pre> <result> = urem <ty> <var1>, <var2> <i>; yields {ty}:result</i>
+</pre>
+<h5>Overview:</h5>
+<p>The '<tt>urem</tt>' instruction returns the remainder from the
+unsigned division of its two arguments.</p>
+<h5>Arguments:</h5>
+<p>The two arguments to the '<tt>urem</tt>' instruction must be
+<a href="#t_integer">integer</a> values. Both arguments must have identical
+types.</p>
+<h5>Semantics:</h5>
+<p>This instruction returns the unsigned integer <i>remainder</i> of a division.
+This instruction always performs an unsigned division to get the remainder,
+regardless of whether the arguments are unsigned or not.</p>
<h5>Example:</h5>
-<pre> <result> = div int 4, %var <i>; yields {int}:result = 4 / %var</i>
+<pre> <result> = urem i32 4, %var <i>; yields {i32}:result = 4 % %var</i>
</pre>
+
</div>
<!-- _______________________________________________________________________ -->
-<div class="doc_subsubsection"> <a name="i_rem">'<tt>rem</tt>'
+<div class="doc_subsubsection"> <a name="i_srem">'<tt>srem</tt>'
Instruction</a> </div>
<div class="doc_text">
<h5>Syntax:</h5>
-<pre> <result> = rem <ty> <var1>, <var2> <i>; yields {ty}:result</i>
+<pre> <result> = srem <ty> <var1>, <var2> <i>; yields {ty}:result</i>
</pre>
<h5>Overview:</h5>
-<p>The '<tt>rem</tt>' instruction returns the remainder from the
-division of its two operands.</p>
+<p>The '<tt>srem</tt>' instruction returns the remainder from the
+signed division of its two operands.</p>
<h5>Arguments:</h5>
-<p>The two arguments to the '<tt>rem</tt>' instruction must be either <a
- href="#t_integer">integer</a> or <a href="#t_floating">floating point</a>
-values.
-This instruction can also take <a href="#t_packed">packed</a> versions of the values.
-Both arguments must have identical types.</p>
+<p>The two arguments to the '<tt>srem</tt>' instruction must be
+<a href="#t_integer">integer</a> values. Both arguments must have identical
+types.</p>
<h5>Semantics:</h5>
-<p>This returns the <i>remainder</i> of a division (where the result
+<p>This instruction returns the <i>remainder</i> of a division (where the result
has the same sign as the divisor), not the <i>modulus</i> (where the
result has the same sign as the dividend) of a value. For more
-information about the difference, see
: <a
+information about the difference, see <a
href="http://mathforum.org/dr.math/problems/anne.4.28.99.html">The
Math Forum</a>.</p>
<h5>Example:</h5>
-<pre> <result> = rem int 4, %var <i>; yields {int}:result = 4 % %var</i>
+<pre> <result> = srem i32 4, %var <i>; yields {i32}:result = 4 % %var</i>
</pre>
+
</div>
<!-- _______________________________________________________________________ -->
-<div class="doc_subsubsection"> <a name="i_setcc">'<tt>set<i>cc</i></tt>'
-Instructions</a> </div>
+<div class="doc_subsubsection"> <a name="i_frem">'<tt>frem</tt>'
+Instruction</a> </div>
<div class="doc_text">
<h5>Syntax:</h5>
-<pre> <result> = seteq <ty> <var1>, <var2> <i>; yields {bool}:result</i>
- <result> = setne <ty> <var1>, <var2> <i>; yields {bool}:result</i>
- <result> = setlt <ty> <var1>, <var2> <i>; yields {bool}:result</i>
- <result> = setgt <ty> <var1>, <var2> <i>; yields {bool}:result</i>
- <result> = setle <ty> <var1>, <var2> <i>; yields {bool}:result</i>
- <result> = setge <ty> <var1>, <var2> <i>; yields {bool}:result</i>
+<pre> <result> = frem <ty> <var1>, <var2> <i>; yields {ty}:result</i>
</pre>
<h5>Overview:</h5>
-<p>The '<tt>set<i>cc</i></tt>' family of instructions returns a boolean
-value based on a comparison of their two operands.</p>
+<p>The '<tt>frem</tt>' instruction returns the remainder from the
+division of its two operands.</p>
<h5>Arguments:</h5>
-<p>The two arguments to the '<tt>set<i>cc</i></tt>' instructions must
-be of <a href="#t_firstclass">first class</a> type (it is not possible
-to compare '<tt>label</tt>'s, '<tt>array</tt>'s, '<tt>structure</tt>'
-or '<tt>void</tt>' values, etc...). Both arguments must have identical
-types.</p>
+<p>The two arguments to the '<tt>frem</tt>' instruction must be
+<a href="#t_floating">floating point</a> values. Both arguments must have
+identical types.</p>
<h5>Semantics:</h5>
-<p>The '<tt>seteq</tt>' instruction yields a <tt>true</tt> '<tt>bool</tt>'
-value if both operands are equal.<br>
-The '<tt>setne</tt>' instruction yields a <tt>true</tt> '<tt>bool</tt>'
-value if both operands are unequal.<br>
-The '<tt>setlt</tt>' instruction yields a <tt>true</tt> '<tt>bool</tt>'
-value if the first operand is less than the second operand.<br>
-The '<tt>setgt</tt>' instruction yields a <tt>true</tt> '<tt>bool</tt>'
-value if the first operand is greater than the second operand.<br>
-The '<tt>setle</tt>' instruction yields a <tt>true</tt> '<tt>bool</tt>'
-value if the first operand is less than or equal to the second operand.<br>
-The '<tt>setge</tt>' instruction yields a <tt>true</tt> '<tt>bool</tt>'
-value if the first operand is greater than or equal to the second
-operand.</p>
+<p>This instruction returns the <i>remainder</i> of a division.</p>
<h5>Example:</h5>
-<pre> <result> = seteq int 4, 5 <i>; yields {bool}:result = false</i>
- <result> = setne float 4, 5 <i>; yields {bool}:result = true</i>
- <result> = setlt uint 4, 5 <i>; yields {bool}:result = true</i>
- <result> = setgt sbyte 4, 5 <i>; yields {bool}:result = false</i>
- <result> = setle sbyte 4, 5 <i>; yields {bool}:result = true</i>
- <result> = setge sbyte 4, 5 <i>; yields {bool}:result = false</i>
+<pre> <result> = frem float 4.0, %var <i>; yields {float}:result = 4.0 % %var</i>
</pre>
</div>
+
<!-- ======================================================================= -->
<div class="doc_subsection"> <a name="bitwiseops">Bitwise Binary
Operations</a> </div>
</table>
</div>
<h5>Example:</h5>
-<pre> <result> = and int 4, %var <i>; yields {int}:result = 4 & %var</i>
- <result> = and int 15, 40 <i>; yields {int}:result = 8</i>
- <result> = and int 4, 8 <i>; yields {int}:result = 0</i>
+<pre> <result> = and i32 4, %var <i>; yields {i32}:result = 4 & %var</i>
+ <result> = and i32 15, 40 <i>; yields {i32}:result = 8</i>
+ <result> = and i32 4, 8 <i>; yields {i32}:result = 0</i>
</pre>
</div>
<!-- _______________________________________________________________________ -->
</table>
</div>
<h5>Example:</h5>
-<pre> <result> = or int 4, %var <i>; yields {int}:result = 4 | %var</i>
- <result> = or int 15, 40 <i>; yields {int}:result = 47</i>
- <result> = or int 4, 8 <i>; yields {int}:result = 12</i>
+<pre> <result> = or i32 4, %var <i>; yields {i32}:result = 4 | %var</i>
+ <result> = or i32 15, 40 <i>; yields {i32}:result = 47</i>
+ <result> = or i32 4, 8 <i>; yields {i32}:result = 12</i>
</pre>
</div>
<!-- _______________________________________________________________________ -->
</div>
<p> </p>
<h5>Example:</h5>
-<pre> <result> = xor int 4, %var <i>; yields {int}:result = 4 ^ %var</i>
- <result> = xor int 15, 40 <i>; yields {int}:result = 39</i>
- <result> = xor int 4, 8 <i>; yields {int}:result = 12</i>
- <result> = xor int %V, -1 <i>; yields {int}:result = ~%V</i>
+<pre> <result> = xor i32 4, %var <i>; yields {i32}:result = 4 ^ %var</i>
+ <result> = xor i32 15, 40 <i>; yields {i32}:result = 39</i>
+ <result> = xor i32 4, 8 <i>; yields {i32}:result = 12</i>
+ <result> = xor i32 %V, -1 <i>; yields {i32}:result = ~%V</i>
</pre>
</div>
<!-- _______________________________________________________________________ -->
Instruction</a> </div>
<div class="doc_text">
<h5>Syntax:</h5>
-<pre> <result> = shl <ty> <var1>, ubyte <var2> <i>; yields {ty}:result</i>
+<pre> <result> = shl <ty> <var1>, i8 <var2> <i>; yields {ty}:result</i>
</pre>
<h5>Overview:</h5>
<p>The '<tt>shl</tt>' instruction returns the first operand shifted to
the left a specified number of bits.</p>
<h5>Arguments:</h5>
<p>The first argument to the '<tt>shl</tt>' instruction must be an <a
- href="#t_integer">integer</a> type. The second argument must be an '<tt>ubyte</tt>'
+ href="#t_integer">integer</a> type. The second argument must be an '<tt>i8</tt>'
type.</p>
<h5>Semantics:</h5>
<p>The value produced is <tt>var1</tt> * 2<sup><tt>var2</tt></sup>.</p>
<h5>Example:</h5>
-<pre> <result> = shl int 4, ubyte %var <i>; yields {int}:result = 4 << %var</i>
- <result> = shl int 4, ubyte 2 <i>; yields {int}:result = 16</i>
- <result> = shl int 1, ubyte 10 <i>; yields {int}:result = 1024</i>
+<pre> <result> = shl i32 4, i8 %var <i>; yields {i32}:result = 4 << %var</i>
+ <result> = shl i32 4, i8 2 <i>; yields {i32}:result = 16</i>
+ <result> = shl i32 1, i8 10 <i>; yields {i32}:result = 1024</i>
</pre>
</div>
<!-- _______________________________________________________________________ -->
-<div class="doc_subsubsection"> <a name="i_shr">'<tt>shr</tt>'
+<div class="doc_subsubsection"> <a name="i_lshr">'<tt>lshr</tt>'
Instruction</a> </div>
<div class="doc_text">
<h5>Syntax:</h5>
-<pre> <result> = shr <ty> <var1>, ubyte <var2> <i>; yields {ty}:result</i>
+<pre> <result> = lshr <ty> <var1>, i8 <var2> <i>; yields {ty}:result</i>
</pre>
+
<h5>Overview:</h5>
-<p>The '<tt>shr</tt>' instruction returns the first operand shifted to
-the right a specified number of bits.</p>
+<p>The '<tt>lshr</tt>' instruction (logical shift right) returns the first
+operand shifted to the right a specified number of bits.</p>
+
<h5>Arguments:</h5>
-<p>The first argument to the '<tt>shr</tt>' instruction must be an <a
- href="#t_integer">integer</a> type. The second argument must be an '<tt>ubyte</tt>'
-type.</p>
+<p>The first argument to the '<tt>
lshr</tt>' instruction must be an <a
+ href="#t_integer">integer</a> type. The second argument must be an '<tt>i8</tt>' type.</p>
+
<h5>Semantics:</h5>
-<p>If the first argument is a <a href="#t_signed">signed</a> type, the
-most significant bit is duplicated in the newly free'd bit positions.
-If the first argument is unsigned, zero bits shall fill the empty
-positions.</p>
+<p>This instruction always performs a logical shift right operation. The
+<tt>var2</tt> most significant bits will be filled with zero bits after the
+shift.</p>
+
<h5>Example:</h5>
-<pre> <result> = shr int 4, ubyte %var <i>; yields {int}:result = 4 >> %var</i>
- <result> = shr uint 4, ubyte 1 <i>; yields {uint}:result = 2</i>
- <result> = shr int 4, ubyte 2 <i>; yields {int}:result = 1</i>
- <result> = shr sbyte 4, ubyte 3 <i>; yields {sbyte}:result = 0</i>
- <result> = shr sbyte -2, ubyte 1 <i>; yields {sbyte}:result = -1</i>
+<pre>
+ <result> = lshr i32 4, i8 1 <i>; yields {i32}:result = 2</i>
+ <result> = lshr i32 4, i8 2 <i>; yields {i32}:result = 1</i>
+ <result> = lshr i8 4, i8 3 <i>; yields {i8 }:result = 0</i>
+ <result> = lshr i8 -2, i8 1 <i>; yields {i8 }:result = 0x7FFFFFFF </i>
</pre>
</div>
+
<!-- ======================================================================= -->
-<div class="doc_subsection"> <a name="memoryops">Memory Access
-Operations</a></div>
-<div class="doc_text">
-<p>A key design point of an SSA-based representation is how it
-represents memory. In LLVM, no memory locations are in SSA form, which
-makes things very simple. This section describes how to read, write,
-allocate, and free memory in LLVM.</p>
-</div>
-<!-- _______________________________________________________________________ -->
-<div class="doc_subsubsection"> <a name="i_malloc">'<tt>malloc</tt>'
+<div class="doc_subsubsection"> <a name="i_ashr">'<tt>ashr</tt>'
Instruction</a> </div>
<div class="doc_text">
+
<h5>Syntax:</h5>
-<pre> <result> = malloc <type>, uint <NumElements> <i>; yields {type*}:result</i>
- <result> = malloc <type> <i>; yields {type*}:result</i>
+<pre> <result> = ashr <ty> <var1>, i8 <var2> <i>; yields {ty}:result</i>
</pre>
+
<h5>Overview:</h5>
-<p>The '<tt>malloc</tt>' instruction allocates memory from the system
-heap and returns a pointer to it.</p>
+<p>The '<tt>ashr</tt>' instruction (arithmetic shift right) returns the first
+operand shifted to the right a specified number of bits.</p>
+
<h5>Arguments:</h5>
-<p>The '<tt>malloc</tt>' instruction allocates <tt>sizeof(<type>)*NumElements</tt>
-bytes of memory from the operating system and returns a pointer of the
-appropriate type to the program. The second form of the instruction is
-a shorter version of the first instruction that defaults to allocating
-one element.</p>
-<p>'<tt>type</tt>' must be a sized type.</p>
+<p>The first argument to the '<tt>ashr</tt>' instruction must be an
+<a href="#t_integer">integer</a> type. The second argument must be an
+'<tt>i8</tt>' type.</p>
+
<h5>Semantics:</h5>
-<p>Memory is allocated using the system "<tt>malloc</tt>" function, and
-a pointer is returned.</p>
-<h5>Example:</h5>
-<pre> %array = malloc [4 x ubyte ] <i>; yields {[%4 x ubyte]*}:array</i>
+<p>This instruction always performs an arithmetic shift right operation,
+regardless of whether the arguments are signed or not. The <tt>var2</tt> most
+significant bits will be filled with the sign bit of <tt>var1</tt>.</p>
- %size = <a
- href="#i_add">add</a> uint 2, 2 <i>; yields {uint}:size = uint 4</i>
- %array1 = malloc ubyte, uint 4 <i>; yields {ubyte*}:array1</i>
- %array2 = malloc [12 x ubyte], uint %size <i>; yields {[12 x ubyte]*}:array2</i>
+<h5>Example:</h5>
+<pre>
+ <result> = ashr i32 4, i8 1 <i>; yields {i32}:result = 2</i>
+ <result> = ashr i32 4, i8 2 <i>; yields {i32}:result = 1</i>
+ <result> = ashr i8 4, i8 3 <i>; yields {i8}:result = 0</i>
+ <result> = ashr i8 -2, i8 1 <i>; yields {i8 }:result = -1</i>
</pre>
</div>
+
+<!-- ======================================================================= -->
+<div class="doc_subsection">
+ <a name="vectorops">Vector Operations</a>
+</div>
+
+<div class="doc_text">
+
+<p>LLVM supports several instructions to represent vector operations in a
+target-independent manner. This instructions cover the element-access and
+vector-specific operations needed to process vectors effectively. While LLVM
+does directly support these vector operations, many sophisticated algorithms
+will want to use target-specific intrinsics to take full advantage of a specific
+target.</p>
+
+</div>
+
<!-- _______________________________________________________________________ -->
-<div class="doc_subsubsection"> <a name="i_free">'<tt>free</tt>'
-Instruction</a> </div>
+<div class="doc_subsubsection">
+ <a name="i_extractelement">'<tt>extractelement</tt>' Instruction</a>
+</div>
+
<div class="doc_text">
+
<h5>Syntax:</h5>
-<pre> free <type> <value> <i>; yields {void}</i>
+
+<pre>
+ <result> = extractelement <n x <ty>> <val>, i32 <idx> <i>; yields <ty></i>
</pre>
+
<h5>Overview:</h5>
-<p>The '<tt>free</tt>' instruction returns memory back to the unused
-memory heap, to be reallocated in the future.</p>
-<p> </p>
+
+<p>
+The '<tt>extractelement</tt>' instruction extracts a single scalar
+element from a packed vector at a specified index.
+</p>
+
+
<h5>Arguments:</h5>
-<p>'<tt>value</tt>' shall be a pointer value that points to a value
-that was allocated with the '<tt><a href="#i_malloc">malloc</a></tt>'
-instruction.</p>
+
+<p>
+The first operand of an '<tt>extractelement</tt>' instruction is a
+value of <a href="#t_packed">packed</a> type. The second operand is
+an index indicating the position from which to extract the element.
+The index may be a variable.</p>
+
<h5>Semantics:</h5>
-<p>Access to the memory pointed to by the pointer is no longer defined
-after this instruction executes.</p>
+
+<p>
+The result is a scalar of the same type as the element type of
+<tt>val</tt>. Its value is the value at position <tt>idx</tt> of
+<tt>val</tt>. If <tt>idx</tt> exceeds the length of <tt>val</tt>, the
+results are undefined.
+</p>
+
<h5>Example:</h5>
-<pre> %array = <a href="#i_malloc">malloc</a> [4 x ubyte] <i>; yields {[4 x ubyte]*}:array</i>
- free [4 x ubyte]* %array
+
+<pre>
+ %result = extractelement <4 x i32> %vec, i32 0 <i>; yields i32</i>
</pre>
</div>
+
+
<!-- _______________________________________________________________________ -->
-<div class="doc_subsubsection"> <a name="i_alloca">'<tt>alloca</tt>'
-Instruction</a> </div>
+<div class="doc_subsubsection">
+ <a name="i_insertelement">'<tt>insertelement</tt>' Instruction</a>
+</div>
+
<div class="doc_text">
+
<h5>Syntax:</h5>
-<pre> <result> = alloca <type>, uint <NumElements> <i>; yields {type*}:result</i>
- <result> = alloca <type> <i>; yields {type*}:result</i>
+
+<pre>
+ <result> = insertelement <n x <ty>> <val>, <ty> <elt>, i32 <idx> <i>; yields <n x <ty>></i>
</pre>
+
<h5>Overview:</h5>
-<p>The '<tt>alloca</tt>' instruction allocates memory on the current
-stack frame of the procedure that is live until the current function
+
+<p>
+The '<tt>insertelement</tt>' instruction inserts a scalar
+element into a packed vector at a specified index.
+</p>
+
+
+<h5>Arguments:</h5>
+
+<p>
+The first operand of an '<tt>insertelement</tt>' instruction is a
+value of <a href="#t_packed">packed</a> type. The second operand is a
+scalar value whose type must equal the element type of the first
+operand. The third operand is an index indicating the position at
+which to insert the value. The index may be a variable.</p>
+
+<h5>Semantics:</h5>
+
+<p>
+The result is a packed vector of the same type as <tt>val</tt>. Its
+element values are those of <tt>val</tt> except at position
+<tt>idx</tt>, where it gets the value <tt>elt</tt>. If <tt>idx</tt>
+exceeds the length of <tt>val</tt>, the results are undefined.
+</p>
+
+<h5>Example:</h5>
+
+<pre>
+ %result = insertelement <4 x i32> %vec, i32 1, i32 0 <i>; yields <4 x i32></i>
+</pre>
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="i_shufflevector">'<tt>shufflevector</tt>' Instruction</a>
+</div>
+
+<div class="doc_text">
+
+<h5>Syntax:</h5>
+
+<pre>
+ <result> = shufflevector <n x <ty>> <v1>, <n x <ty>> <v2>, <n x i32> <mask> <i>; yields <n x <ty>></i>
+</pre>
+
+<h5>Overview:</h5>
+
+<p>
+The '<tt>shufflevector</tt>' instruction constructs a permutation of elements
+from two input vectors, returning a vector of the same type.
+</p>
+
+<h5>Arguments:</h5>
+
+<p>
+The first two operands of a '<tt>shufflevector</tt>' instruction are vectors
+with types that match each other and types that match the result of the
+instruction. The third argument is a shuffle mask, which has the same number
+of elements as the other vector type, but whose element type is always 'i32'.
+</p>
+
+<p>
+The shuffle mask operand is required to be a constant vector with either
+constant integer or undef values.
+</p>
+
+<h5>Semantics:</h5>
+
+<p>
+The elements of the two input vectors are numbered from left to right across
+both of the vectors. The shuffle mask operand specifies, for each element of
+the result vector, which element of the two input registers the result element
+gets. The element selector may be undef (meaning "don't care") and the second
+operand may be undef if performing a shuffle from only one vector.
+</p>
+
+<h5>Example:</h5>
+
+<pre>
+ %result = shufflevector <4 x i32> %v1, <4 x i32> %v2,
+ <4 x i32> <i32 0, i32 4, i32 1, i32 5> <i>; yields <4 x i32></i>
+ %result = shufflevector <4 x i32> %v1, <4 x i32> undef,
+ <4 x i32> <i32 0, i32 1, i32 2, i32 3> <i>; yields <4 x i32></i> - Identity shuffle.
+</pre>
+</div>
+
+
+<!-- ======================================================================= -->
+<div class="doc_subsection">
+ <a name="memoryops">Memory Access and Addressing Operations</a>
+</div>
+
+<div class="doc_text">
+
+<p>A key design point of an SSA-based representation is how it
+represents memory. In LLVM, no memory locations are in SSA form, which
+makes things very simple. This section describes how to read, write,
+allocate, and free memory in LLVM.</p>
+
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="i_malloc">'<tt>malloc</tt>' Instruction</a>
+</div>
+
+<div class="doc_text">
+
+<h5>Syntax:</h5>
+
+<pre>
+ <result> = malloc <type>[, i32 <NumElements>][, align <alignment>] <i>; yields {type*}:result</i>
+</pre>
+
+<h5>Overview:</h5>
+
+<p>The '<tt>malloc</tt>' instruction allocates memory from the system
+heap and returns a pointer to it.</p>
+
+<h5>Arguments:</h5>
+
+<p>The '<tt>malloc</tt>' instruction allocates
+<tt>sizeof(<type>)*NumElements</tt>
+bytes of memory from the operating system and returns a pointer of the
+appropriate type to the program. If "NumElements" is specified, it is the
+number of elements allocated. If an alignment is specified, the value result
+of the allocation is guaranteed to be aligned to at least that boundary. If
+not specified, or if zero, the target can choose to align the allocation on any
+convenient boundary.</p>
+
+<p>'<tt>type</tt>' must be a sized type.</p>
+
+<h5>Semantics:</h5>
+
+<p>Memory is allocated using the system "<tt>malloc</tt>" function, and
+a pointer is returned.</p>
+
+<h5>Example:</h5>
+
+<pre>
+ %array = malloc [4 x i8 ] <i>; yields {[%4 x i8]*}:array</i>
+
+ %size = <a href="#i_add">add</a> i32 2, 2 <i>; yields {i32}:size = i32 4</i>
+ %array1 = malloc i8, i32 4 <i>; yields {i8*}:array1</i>
+ %array2 = malloc [12 x i8], i32 %size <i>; yields {[12 x i8]*}:array2</i>
+ %array3 = malloc i32, i32 4, align 1024 <i>; yields {i32*}:array3</i>
+ %array4 = malloc i32, align 1024 <i>; yields {i32*}:array4</i>
+</pre>
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="i_free">'<tt>free</tt>' Instruction</a>
+</div>
+
+<div class="doc_text">
+
+<h5>Syntax:</h5>
+
+<pre>
+ free <type> <value> <i>; yields {void}</i>
+</pre>
+
+<h5>Overview:</h5>
+
+<p>The '<tt>free</tt>' instruction returns memory back to the unused
+memory heap to be reallocated in the future.</p>
+
+<h5>Arguments:</h5>
+
+<p>'<tt>value</tt>' shall be a pointer value that points to a value
+that was allocated with the '<tt><a href="#i_malloc">malloc</a></tt>'
+instruction.</p>
+
+<h5>Semantics:</h5>
+
+<p>Access to the memory pointed to by the pointer is no longer defined
+after this instruction executes.</p>
+
+<h5>Example:</h5>
+
+<pre>
+ %array = <a href="#i_malloc">malloc</a> [4 x i8] <i>; yields {[4 x i8]*}:array</i>
+ free [4 x i8]* %array
+</pre>
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="i_alloca">'<tt>alloca</tt>' Instruction</a>
+</div>
+
+<div class="doc_text">
+
+<h5>Syntax:</h5>
+
+<pre>
+ <result> = alloca <type>[, i32 <NumElements>][, align <alignment>] <i>; yields {type*}:result</i>
+</pre>
+
+<h5>Overview:</h5>
+
+<p>The '<tt>alloca</tt>' instruction allocates memory on the current
+stack frame of the procedure that is live until the current function
returns to its caller.</p>
+
<h5>Arguments:</h5>
+
<p>The '<tt>alloca</tt>' instruction allocates <tt>sizeof(<type>)*NumElements</tt>
bytes of memory on the runtime stack, returning a pointer of the
-appropriate type to the program. The second form of the instruction is
-a shorter version of the first that defaults to allocating one element.</p>
+appropriate type to the program. If "NumElements" is specified, it is the
+number of elements allocated. If an alignment is specified, the value result
+of the allocation is guaranteed to be aligned to at least that boundary. If
+not specified, or if zero, the target can choose to align the allocation on any
+convenient boundary.</p>
+
<p>'<tt>type</tt>' may be any sized type.</p>
+
<h5>Semantics:</h5>
-<p>Memory is allocated, a pointer is returned. '<tt>alloca</tt>'d
+
+<p>Memory is allocated; a pointer is returned. '<tt>alloca</tt>'d
memory is automatically released when the function returns. The '<tt>alloca</tt>'
instruction is commonly used to represent automatic variables that must
have an address available. When the function returns (either with the <tt><a
- href="#i_ret">ret</a></tt> or <tt><a href="#i_invoke">invoke</a></tt>
+ href="#i_ret">ret</a></tt> or <tt><a href="#i_unwind">unwind</a></tt>
instructions), the memory is reclaimed.</p>
+
<h5>Example:</h5>
-<pre> %ptr = alloca int <i>; yields {int*}:ptr</i>
- %ptr = alloca int, uint 4 <i>; yields {int*}:ptr</i>
+
+<pre>
+ %ptr = alloca i32 <i>; yields {i32*}:ptr</i>
+ %ptr = alloca i32, i32 4 <i>; yields {i32*}:ptr</i>
+ %ptr = alloca i32, i32 4, align 1024 <i>; yields {i32*}:ptr</i>
+ %ptr = alloca i32, align 1024 <i>; yields {i32*}:ptr</i>
</pre>
</div>
+
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection"> <a name="i_load">'<tt>load</tt>'
Instruction</a> </div>
<p>The '<tt>load</tt>' instruction is used to read from memory.</p>
<h5>Arguments:</h5>
<p>The argument to the '<tt>load</tt>' instruction specifies the memory
-address
to load from. The pointer must point to a <a
+address
from which to load. The pointer must point to a <a
href="#t_firstclass">first class</a> type. If the <tt>load</tt> is
-marked as <tt>volatile</tt> then the optimizer is not allowed to modify
+marked as <tt>volatile</tt>, then the optimizer is not allowed to modify
the number or order of execution of this <tt>load</tt> with other
volatile <tt>load</tt> and <tt><a href="#i_store">store</a></tt>
instructions. </p>
<h5>Semantics:</h5>
<p>The location of memory pointed to is loaded.</p>
<h5>Examples:</h5>
-<pre> %ptr = <a href="#i_alloca">alloca</a> int <i>; yields {int*}:ptr</i>
+<pre> %ptr = <a href="#i_alloca">alloca</a> i32 <i>; yields {i32*}:ptr</i>
<a
- href="#i_store">store</a> int 3, int* %ptr <i>; yields {void}</i>
- %val = load int* %ptr <i>; yields {int}:val = int 3</i>
+ href="#i_store">store</a> i32 3, i32* %ptr <i>; yields {void}</i>
+ %val = load i32* %ptr <i>; yields {i32}:val = i32 3</i>
</pre>
</div>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection"> <a name="i_store">'<tt>store</tt>'
Instruction</a> </div>
+<div class="doc_text">
<h5>Syntax:</h5>
<pre> store <ty> <value>, <ty>* <pointer> <i>; yields {void}</i>
volatile store <ty> <value>, <ty>* <pointer> <i>; yields {void}</i>
<p>The '<tt>store</tt>' instruction is used to write to memory.</p>
<h5>Arguments:</h5>
<p>There are two arguments to the '<tt>store</tt>' instruction: a value
-to store and an address to store it into. The type of the '<tt><pointer></tt>'
+to store and an address in which to store it. The type of the '<tt><pointer></tt>'
operand must be a pointer to the type of the '<tt><value></tt>'
-operand. If the <tt>store</tt> is marked as <tt>volatile</tt> then the
+operand. If the <tt>store</tt> is marked as <tt>volatile</tt>, then the
optimizer is not allowed to modify the number or order of execution of
this <tt>store</tt> with other volatile <tt>load</tt> and <tt><a
href="#i_store">store</a></tt> instructions.</p>
<p>The contents of memory are updated to contain '<tt><value></tt>'
at the location specified by the '<tt><pointer></tt>' operand.</p>
<h5>Example:</h5>
-<pre> %ptr = <a href="#i_alloca">alloca</a> int <i>; yields {int*}:ptr</i>
+<pre> %ptr = <a href="#i_alloca">alloca</a> i32 <i>; yields {i32*}:ptr</i>
<a
- href="#i_store">store</a> int 3, int* %ptr <i>; yields {void}</i>
- %val = load int* %ptr <i>; yields {int}:val = int 3</i>
+ href="#i_store">store</a> i32 3, i32* %ptr <i>; yields {void}</i>
+ %val = load i32* %ptr <i>; yields {i32}:val = i32 3</i>
</pre>
+</div>
+
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
<a name="i_getelementptr">'<tt>getelementptr</tt>' Instruction</a>
<h5>Arguments:</h5>
-<p>This instruction takes a list of integer constants that indicate what
+<p>This instruction takes a list of integer operands that indicate what
elements of the aggregate object to index to. The actual types of the arguments
provided depend on the type of the first pointer argument. The
'<tt>getelementptr</tt>' instruction is used to index down through the type
-levels of a structure. When indexing into a structure, only <tt>uint</tt>
-integer constants are allowed. When indexing into an array or pointer
-<tt>int</tt> and <tt>long</tt> indexes are allowed of any sign.</p>
+levels of a structure or to a specific index in an array. When indexing into a
+structure, only <tt>i32</tt> integer constants are allowed. When indexing
+into an array or pointer, only integers of 32 or 64 bits are allowed, and will
+be sign extended to 64-bit values.</p>
<p>For example, let's consider a C code fragment and how it gets
compiled to LLVM:</p>
<pre>
struct RT {
char A;
- int B[10][20];
+ i32 B[10][20];
char C;
};
struct ST {
- int X;
+ i32 X;
double Y;
struct RT Z;
};
- int *foo(struct ST *s) {
+ define i32 *foo(struct ST *s) {
return &s[1].Z.B[5][13];
}
</pre>
<p>The LLVM code generated by the GCC frontend is:</p>
<pre>
- %RT = type { sbyte, [10 x [20 x int]], sbyte }
- %ST = type { int, double, %RT }
+ %RT = type { i8 , [10 x [20 x i32]], i8 }
+ %ST = type { i32, double, %RT }
implementation
- int* %foo(%ST* %s) {
+ define i32* %foo(%ST* %s) {
entry:
- %reg = getelementptr %ST* %s, int 1, uint 2, uint 1, int 5, int 13
- ret int* %reg
+ %reg = getelementptr %ST* %s, i32 1, i32 2, i32 1, i32 5, i32 13
+ ret i32* %reg
}
</pre>
<h5>Semantics:</h5>
<p>The index types specified for the '<tt>getelementptr</tt>' instruction depend
-on the pointer type that is being index into. <a href="#t_pointer">Pointer</a>
-and <a href="#t_array">array</a> types require <tt>uint</tt>, <tt>int</tt>,
-<tt>ulong</tt>, or <tt>long</tt> values, and <a href="#t_struct">structure</a>
-types require <tt>uint</tt> <b>constants</b>.</p>
+on the pointer type that is being indexed into. <a href="#t_pointer">Pointer</a>
+and <a href="#t_array">array</a> types can use a 32-bit or 64-bit
+<a href="#t_integer">integer</a> type but the value will always be sign extended
+to 64-bits. <a href="#t_struct">Structure</a> types, require <tt>i32</tt>
+<b>constants</b>.</p>
<p>In the example above, the first index is indexing into the '<tt>%ST*</tt>'
-type, which is a pointer, yielding a '<tt>%ST</tt>' = '<tt>{ int, double, %RT
+type, which is a pointer, yielding a '<tt>%ST</tt>' = '<tt>{ i32, double, %RT
}</tt>' type, a structure. The second index indexes into the third element of
-the structure, yielding a '<tt>%RT</tt>' = '<tt>{ sbyte, [10 x [20 x int]],
-sbyte }</tt>' type, another structure. The third index indexes into the second
-element of the structure, yielding a '<tt>[10 x [20 x int]]</tt>' type, an
+the structure, yielding a '<tt>%RT</tt>' = '<tt>{ i8 , [10 x [20 x i32]],
+i8 }</tt>' type, another structure. The third index indexes into the second
+element of the structure, yielding a '<tt>[10 x [20 x i32]]</tt>' type, an
array. The two dimensions of the array are subscripted into, yielding an
-'<tt>int</tt>' type. The '<tt>getelementptr</tt>' instruction return a pointer
-to this element, thus computing a value of '<tt>int*</tt>' type.</p>
+'<tt>i32</tt>' type. The '<tt>getelementptr</tt>' instruction returns a pointer
+to this element, thus computing a value of '<tt>i32*</tt>' type.</p>
<p>Note that it is perfectly legal to index partially through a
structure, returning a pointer to an inner element. Because of this,
the LLVM code for the given testcase is equivalent to:</p>
<pre>
- int* %foo(%ST* %s) {
- %t1 = getelementptr %ST* %s, int 1 <i>; yields %ST*:%t1</i>
- %t2 = getelementptr %ST* %t1, int 0, uint 2 <i>; yields %RT*:%t2</i>
- %t3 = getelementptr %RT* %t2, int 0, uint 1 <i>; yields [10 x [20 x int]]*:%t3</i>
- %t4 = getelementptr [10 x [20 x int]]* %t3, int 0, int 5 <i>; yields [20 x int]*:%t4</i>
- %t5 = getelementptr [20 x int]* %t4, int 0, int 13 <i>; yields int*:%t5</i>
- ret int* %t5
+ define i32* %foo(%ST* %s) {
+ %t1 = getelementptr %ST* %s, i32 1 <i>; yields %ST*:%t1</i>
+ %t2 = getelementptr %ST* %t1, i32 0, i32 2 <i>; yields %RT*:%t2</i>
+ %t3 = getelementptr %RT* %t2, i32 0, i32 1 <i>; yields [10 x [20 x i32]]*:%t3</i>
+ %t4 = getelementptr [10 x [20 x i32]]* %t3, i32 0, i32 5 <i>; yields [20 x i32]*:%t4</i>
+ %t5 = getelementptr [20 x i32]* %t4, i32 0, i32 13 <i>; yields i32*:%t5</i>
+ ret i32* %t5
}
</pre>
+
+<p>Note that it is undefined to access an array out of bounds: array and
+pointer indexes must always be within the defined bounds of the array type.
+The one exception for this rules is zero length arrays. These arrays are
+defined to be accessible as variable length arrays, which requires access
+beyond the zero'th element.</p>
+
+<p>The getelementptr instruction is often confusing. For some more insight
+into how it works, see <a href="GetElementPtr.html">the getelementptr
+FAQ</a>.</p>
+
<h5>Example:</h5>
+
<pre>
- <i>; yields [12 x ubyte]*:aptr</i>
- %aptr = getelementptr {int, [12 x ubyte]}* %sptr, long 0, uint 1
+ <i>; yields [12 x i8]*:aptr</i>
+ %aptr = getelementptr {i32, [12 x i8]}* %sptr, i64 0, i32 1
</pre>
-
</div>
+
<!-- ======================================================================= -->
-<div class="doc_subsection"> <a name="otherops">Other Operations</a> </div>
+<div class="doc_subsection"> <a name="convertops">Conversion Operations</a>
+</div>
<div class="doc_text">
-<p>The instructions in this category are the "miscellaneous"
-instructions, which defy better classification.</p>
+<p>The instructions in this category are the conversion instructions (casting)
+which all take a single operand and a type. They perform various bit conversions
+on the operand.</p>
</div>
+
<!-- _______________________________________________________________________ -->
-<div class="doc_subsubsection"> <a name="i_phi">'<tt>phi</tt>'
-Instruction</a> </div>
+<div class="doc_subsubsection">
+ <a name="i_trunc">'<tt>trunc .. to</tt>' Instruction</a>
+</div>
<div class="doc_text">
+
<h5>Syntax:</h5>
-<pre> <result> = phi <ty> [ <val0>, <label0>], ...<br></pre>
+<pre>
+ <result> = trunc <ty> <value> to <ty2> <i>; yields ty2</i>
+</pre>
+
<h5>Overview:</h5>
-<p>The '<tt>phi</tt>' instruction is used to implement the φ node in
-the SSA graph representing the function.</p>
+<p>
+The '<tt>trunc</tt>' instruction truncates its operand to the type <tt>ty2</tt>.
+</p>
+
<h5>Arguments:</h5>
-<p>The type of the incoming values are specified with the first type
-field. After this, the '<tt>phi</tt>' instruction takes a list of pairs
-as arguments, with one pair for each predecessor basic block of the
-current block. Only values of <a href="#t_firstclass">first class</a>
-type may be used as the value arguments to the PHI node. Only labels
-may be used as the label arguments.</p>
-<p>There must be no non-phi instructions between the start of a basic
-block and the PHI instructions: i.e. PHI instructions must be first in
-a basic block.</p>
+<p>
+The '<tt>trunc</tt>' instruction takes a <tt>value</tt> to trunc, which must
+be an <a href="#t_integer">integer</a> type, and a type that specifies the size
+and type of the result, which must be an <a href="#t_integral">integral</a>
+type. The bit size of <tt>value</tt> must be larger than the bit size of
+<tt>ty2</tt>. Equal sized types are not allowed.</p>
+
<h5>Semantics:</h5>
-<p>At runtime, the '<tt>phi</tt>' instruction logically takes on the
-value specified by the parameter, depending on which basic block we
-came from in the last <a href="#terminators">terminator</a> instruction.</p>
+<p>
+The '<tt>trunc</tt>' instruction truncates the high order bits in <tt>value</tt>
+and converts the remaining bits to <tt>ty2</tt>. Since the source size must be
+larger than the destination size, <tt>trunc</tt> cannot be a <i>no-op cast</i>.
+It will always truncate bits.</p>
+
<h5>Example:</h5>
-<pre>Loop: ; Infinite loop that counts from 0 on up...<br> %indvar = phi uint [ 0, %LoopHeader ], [ %nextindvar, %Loop ]<br> %nextindvar = add uint %indvar, 1<br> br label %Loop<br></pre>
+<pre>
+ %X = trunc i32 257 to i8 <i>; yields i8:1</i>
+ %Y = trunc i32 123 to bool <i>; yields bool:true</i>
+</pre>
</div>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_cast">'<tt>cast .. to</tt>' Instruction</a>
+ <a name="i_zext">'<tt>zext .. to</tt>' Instruction</a>
</div>
-
<div class="doc_text">
<h5>Syntax:</h5>
+<pre>
+ <result> = zext <ty> <value> to <ty2> <i>; yields ty2</i>
+</pre>
+
+<h5>Overview:</h5>
+<p>The '<tt>zext</tt>' instruction zero extends its operand to type
+<tt>ty2</tt>.</p>
+
+
+<h5>Arguments:</h5>
+<p>The '<tt>zext</tt>' instruction takes a value to cast, which must be of
+<a href="#t_integral">integral</a> type, and a type to cast it to, which must
+also be of <a href="#t_integral">integral</a> type. The bit size of the
+<tt>value</tt> must be smaller than the bit size of the destination type,
+<tt>ty2</tt>.</p>
+
+<h5>Semantics:</h5>
+<p>The <tt>zext</tt> fills the high order bits of the <tt>value</tt> with zero
+bits until it reaches the size of the destination type, <tt>ty2</tt>. When the
+the operand and the type are the same size, no bit filling is done and the
+cast is considered a <i>no-op cast</i> because no bits change (only the type
+changes).</p>
+
+<p>When zero extending from bool, the result will alwasy be either 0 or 1.</p>
+<h5>Example:</h5>
+<pre>
+ %X = zext i32 257 to i64 <i>; yields i64:257</i>
+ %Y = zext bool true to i32 <i>; yields i32:1</i>
+</pre>
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="i_sext">'<tt>sext .. to</tt>' Instruction</a>
+</div>
+<div class="doc_text">
+
+<h5>Syntax:</h5>
<pre>
- <result> = cast <ty> <value> to <ty2> <i>; yields ty2</i>
+ <result> = sext <ty> <value> to <ty2> <i>; yields ty2</i>
</pre>
<h5>Overview:</h5>
+<p>The '<tt>sext</tt>' sign extends <tt>value</tt> to the type <tt>ty2</tt>.</p>
+<h5>Arguments:</h5>
<p>
-The '<tt>cast</tt>' instruction is used as the primitive means to convert
-integers to floating point, change data type sizes, and break type safety (by
-casting pointers).
-</p>
+The '<tt>sext</tt>' instruction takes a value to cast, which must be of
+<a href="#t_integral">integral</a> type, and a type to cast it to, which must
+also be of <a href="#t_integral">integral</a> type. The bit size of the
+<tt>value</tt> must be smaller than the bit size of the destination type,
+<tt>ty2</tt>.</p>
+
+<h5>Semantics:</h5>
+<p>
+The '<tt>sext</tt>' instruction performs a sign extension by copying the sign
+bit (highest order bit) of the <tt>value</tt> until it reaches the bit size of
+the type <tt>ty2</tt>. When the the operand and the type are the same size,
+no bit filling is done and the cast is considered a <i>no-op cast</i> because
+no bits change (only the type changes).</p>
+
+<p>When sign extending from bool, the extension always results in -1 or 0.</p>
+
+<h5>Example:</h5>
+<pre>
+ %X = sext i8 -1 to i16 <i>; yields i16 :65535</i>
+ %Y = sext bool true to i32 <i>; yields i32:-1</i>
+</pre>
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="i_fptrunc">'<tt>fptrunc .. to</tt>' Instruction</a>
+</div>
+
+<div class="doc_text">
+
+<h5>Syntax:</h5>
+
+<pre>
+ <result> = fptrunc <ty> <value> to <ty2> <i>; yields ty2</i>
+</pre>
+
+<h5>Overview:</h5>
+<p>The '<tt>fptrunc</tt>' instruction truncates <tt>value</tt> to type
+<tt>ty2</tt>.</p>
<h5>Arguments:</h5>
+<p>The '<tt>fptrunc</tt>' instruction takes a <a href="#t_floating">floating
+ point</a> value to cast and a <a href="#t_floating">floating point</a> type to
+cast it to. The size of <tt>value</tt> must be larger than the size of
+<tt>ty2</tt>. This implies that <tt>fptrunc</tt> cannot be used to make a
+<i>no-op cast</i>.</p>
-<p>
-The '<tt>cast</tt>' instruction takes a value to cast, which must be a first
-class value, and a type to cast it to, which must also be a <a
-href="#t_firstclass">first class</a> type.
-</p>
+<h5>Semantics:</h5>
+<p> The '<tt>fptrunc</tt>' instruction truncates a <tt>value</tt> from a larger
+<a href="#t_floating">floating point</a> type to a smaller
+<a href="#t_floating">floating point</a> type. If the value cannot fit within
+the destination type, <tt>ty2</tt>, then the results are undefined.</p>
+
+<h5>Example:</h5>
+<pre>
+ %X = fptrunc double 123.0 to float <i>; yields float:123.0</i>
+ %Y = fptrunc double 1.0E+300 to float <i>; yields undefined</i>
+</pre>
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="i_fpext">'<tt>fpext .. to</tt>' Instruction</a>
+</div>
+<div class="doc_text">
+
+<h5>Syntax:</h5>
+<pre>
+ <result> = fpext <ty> <value> to <ty2> <i>; yields ty2</i>
+</pre>
+
+<h5>Overview:</h5>
+<p>The '<tt>fpext</tt>' extends a floating point <tt>value</tt> to a larger
+floating point value.</p>
+
+<h5>Arguments:</h5>
+<p>The '<tt>fpext</tt>' instruction takes a
+<a href="#t_floating">floating point</a> <tt>value</tt> to cast,
+and a <a href="#t_floating">floating point</a> type to cast it to. The source
+type must be smaller than the destination type.</p>
<h5>Semantics:</h5>
+<p>The '<tt>fpext</tt>' instruction extends the <tt>value</tt> from a smaller
+<a href="t_floating">floating point</a> type to a larger
+<a href="t_floating">floating point</a> type. The <tt>fpext</tt> cannot be
+used to make a <i>no-op cast</i> because it always changes bits. Use
+<tt>bitcast</tt> to make a <i>no-op cast</i> for a floating point cast.</p>
-<p>
-This instruction follows the C rules for explicit casts when determining how the
-data being cast must change to fit in its new container.
+<h5>Example:</h5>
+<pre>
+ %X = fpext float 3.1415 to double <i>; yields double:3.1415</i>
+ %Y = fpext float 1.0 to float <i>; yields float:1.0 (no-op)</i>
+</pre>
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="i_fp2uint">'<tt>fptoui .. to</tt>' Instruction</a>
+</div>
+<div class="doc_text">
+
+<h5>Syntax:</h5>
+<pre>
+ <result> = fp2uint <ty> <value> to <ty2> <i>; yields ty2</i>
+</pre>
+
+<h5>Overview:</h5>
+<p>The '<tt>fp2uint</tt>' converts a floating point <tt>value</tt> to its
+unsigned integer equivalent of type <tt>ty2</tt>.
</p>
-<p>
-When casting to bool, any value that would be considered true in the context of
-a C '<tt>if</tt>' condition is converted to the boolean '<tt>true</tt>' values,
-all else are '<tt>false</tt>'.
+<h5>Arguments:</h5>
+<p>The '<tt>fp2uint</tt>' instruction takes a value to cast, which must be a
+<a href="#t_floating">floating point</a> value, and a type to cast it to, which
+must be an <a href="#t_integral">integral</a> type.</p>
+
+<h5>Semantics:</h5>
+<p> The '<tt>fp2uint</tt>' instruction converts its
+<a href="#t_floating">floating point</a> operand into the nearest (rounding
+towards zero) unsigned integer value. If the value cannot fit in <tt>ty2</tt>,
+the results are undefined.</p>
+
+<p>When converting to bool, the conversion is done as a comparison against
+zero. If the <tt>value</tt> was zero, the bool result will be <tt>false</tt>.
+If the <tt>value</tt> was non-zero, the bool result will be <tt>true</tt>.</p>
+
+<h5>Example:</h5>
+<pre>
+ %X = fp2uint double 123.0 to i32 <i>; yields i32:123</i>
+ %Y = fp2uint float 1.0E+300 to bool <i>; yields bool:true</i>
+ %X = fp2uint float 1.04E+17 to i8 <i>; yields undefined:1</i>
+</pre>
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="i_fptosi">'<tt>fptosi .. to</tt>' Instruction</a>
+</div>
+<div class="doc_text">
+
+<h5>Syntax:</h5>
+<pre>
+ <result> = fptosi <ty> <value> to <ty2> <i>; yields ty2</i>
+</pre>
+
+<h5>Overview:</h5>
+<p>The '<tt>fptosi</tt>' instruction converts
+<a href="#t_floating">floating point</a> <tt>value</tt> to type <tt>ty2</tt>.
</p>
-<p>
-When extending an integral value from a type of one signness to another (for
-example '<tt>sbyte</tt>' to '<tt>ulong</tt>'), the value is sign-extended if the
-<b>source</b> value is signed, and zero-extended if the source value is
-unsigned. <tt>bool</tt> values are always zero extended into either zero or
-one.
+
+<h5>Arguments:</h5>
+<p> The '<tt>fptosi</tt>' instruction takes a value to cast, which must be a
+<a href="#t_floating">floating point</a> value, and a type to cast it to, which
+must also be an <a href="#t_integral">integral</a> type.</p>
+
+<h5>Semantics:</h5>
+<p>The '<tt>fptosi</tt>' instruction converts its
+<a href="#t_floating">floating point</a> operand into the nearest (rounding
+towards zero) signed integer value. If the value cannot fit in <tt>ty2</tt>,
+the results are undefined.</p>
+
+<p>When converting to bool, the conversion is done as a comparison against
+zero. If the <tt>value</tt> was zero, the bool result will be <tt>false</tt>.
+If the <tt>value</tt> was non-zero, the bool result will be <tt>true</tt>.</p>
+
+<h5>Example:</h5>
+<pre>
+ %X = fptosi double -123.0 to i32 <i>; yields i32:-123</i>
+ %Y = fptosi float 1.0E-247 to bool <i>; yields bool:true</i>
+ %X = fptosi float 1.04E+17 to i8 <i>; yields undefined:1</i>
+</pre>
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="i_uitofp">'<tt>uitofp .. to</tt>' Instruction</a>
+</div>
+<div class="doc_text">
+
+<h5>Syntax:</h5>
+<pre>
+ <result> = uitofp <ty> <value> to <ty2> <i>; yields ty2</i>
+</pre>
+
+<h5>Overview:</h5>
+<p>The '<tt>uitofp</tt>' instruction regards <tt>value</tt> as an unsigned
+integer and converts that value to the <tt>ty2</tt> type.</p>
+
+
+<h5>Arguments:</h5>
+<p>The '<tt>uitofp</tt>' instruction takes a value to cast, which must be an
+<a href="#t_integral">integral</a> value, and a type to cast it to, which must
+be a <a href="#t_floating">floating point</a> type.</p>
+
+<h5>Semantics:</h5>
+<p>The '<tt>uitofp</tt>' instruction interprets its operand as an unsigned
+integer quantity and converts it to the corresponding floating point value. If
+the value cannot fit in the floating point value, the results are undefined.</p>
+
+
+<h5>Example:</h5>
+<pre>
+ %X = uitofp i32 257 to float <i>; yields float:257.0</i>
+ %Y = uitofp i8 -1 to double <i>; yields double:255.0</i>
+</pre>
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="i_sitofp">'<tt>sitofp .. to</tt>' Instruction</a>
+</div>
+<div class="doc_text">
+
+<h5>Syntax:</h5>
+<pre>
+ <result> = sitofp <ty> <value> to <ty2> <i>; yields ty2</i>
+</pre>
+
+<h5>Overview:</h5>
+<p>The '<tt>sitofp</tt>' instruction regards <tt>value</tt> as a signed
+integer and converts that value to the <tt>ty2</tt> type.</p>
+
+<h5>Arguments:</h5>
+<p>The '<tt>sitofp</tt>' instruction takes a value to cast, which must be an
+<a href="#t_integral">integral</a> value, and a type to cast it to, which must be
+a <a href="#t_floating">floating point</a> type.</p>
+
+<h5>Semantics:</h5>
+<p>The '<tt>sitofp</tt>' instruction interprets its operand as a signed
+integer quantity and converts it to the corresponding floating point value. If
+the value cannot fit in the floating point value, the results are undefined.</p>
+
+<h5>Example:</h5>
+<pre>
+ %X = sitofp i32 257 to float <i>; yields float:257.0</i>
+ %Y = sitofp i8 -1 to double <i>; yields double:-1.0</i>
+</pre>
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="i_ptrtoint">'<tt>ptrtoint .. to</tt>' Instruction</a>
+</div>
+<div class="doc_text">
+
+<h5>Syntax:</h5>
+<pre>
+ <result> = ptrtoint <ty> <value> to <ty2> <i>; yields ty2</i>
+</pre>
+
+<h5>Overview:</h5>
+<p>The '<tt>ptrtoint</tt>' instruction converts the pointer <tt>value</tt> to
+the integer type <tt>ty2</tt>.</p>
+
+<h5>Arguments:</h5>
+<p>The '<tt>ptrtoint</tt>' instruction takes a <tt>value</tt> to cast, which
+must be a <a href="t_pointer">pointer</a> value, and a type to cast it to
+<tt>ty2</tt>, which must be an <a href="#t_integer">integer</a> type.
+
+<h5>Semantics:</h5>
+<p>The '<tt>ptrtoint</tt>' instruction converts <tt>value</tt> to integer type
+<tt>ty2</tt> by interpreting the pointer value as an integer and either
+truncating or zero extending that value to the size of the integer type. If
+<tt>value</tt> is smaller than <tt>ty2</tt> then a zero extension is done. If
+<tt>value</tt> is larger than <tt>ty2</tt> then a truncation is done. If they
+are the same size, then nothing is done (<i>no-op cast</i>).</p>
+
+<h5>Example:</h5>
+<pre>
+ %X = ptrtoint i32* %X to i8 <i>; yields truncation on 32-bit</i>
+ %Y = ptrtoint i32* %x to i64 <i>; yields zero extend on 32-bit</i>
+</pre>
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="i_inttoptr">'<tt>inttoptr .. to</tt>' Instruction</a>
+</div>
+<div class="doc_text">
+
+<h5>Syntax:</h5>
+<pre>
+ <result> = inttoptr <ty> <value> to <ty2> <i>; yields ty2</i>
+</pre>
+
+<h5>Overview:</h5>
+<p>The '<tt>inttoptr</tt>' instruction converts an integer <tt>value</tt> to
+a pointer type, <tt>ty2</tt>.</p>
+
+<h5>Arguments:</h5>
+<p>The '<tt>inttoptr</tt>' instruction takes an <a href="i_integer">integer</a>
+value to cast, and a type to cast it to, which must be a
+<a href="#t_pointer">pointer</a> type. </tt>
+
+<h5>Semantics:</h5>
+<p>The '<tt>inttoptr</tt>' instruction converts <tt>value</tt> to type
+<tt>ty2</tt> by applying either a zero extension or a truncation depending on
+the size of the integer <tt>value</tt>. If <tt>value</tt> is larger than the
+size of a pointer then a truncation is done. If <tt>value</tt> is smaller than
+the size of a pointer then a zero extension is done. If they are the same size,
+nothing is done (<i>no-op cast</i>).</p>
+
+<h5>Example:</h5>
+<pre>
+ %X = inttoptr i32 255 to i32* <i>; yields zero extend on 64-bit</i>
+ %X = inttoptr i32 255 to i32* <i>; yields no-op on 32-bit </i>
+ %Y = inttoptr i16 0 to i32* <i>; yields zero extend on 32-bit</i>
+</pre>
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="i_bitcast">'<tt>bitcast .. to</tt>' Instruction</a>
+</div>
+<div class="doc_text">
+
+<h5>Syntax:</h5>
+<pre>
+ <result> = bitcast <ty> <value> to <ty2> <i>; yields ty2</i>
+</pre>
+
+<h5>Overview:</h5>
+<p>The '<tt>bitcast</tt>' instruction converts <tt>value</tt> to type
+<tt>ty2</tt> without changing any bits.</p>
+
+<h5>Arguments:</h5>
+<p>The '<tt>bitcast</tt>' instruction takes a value to cast, which must be
+a first class value, and a type to cast it to, which must also be a <a
+ href="#t_firstclass">first class</a> type. The bit sizes of <tt>value</tt>
+and the destination type, <tt>ty2</tt>, must be identical.</p>
+
+<h5>Semantics:</h5>
+<p>The '<tt>bitcast</tt>' instruction converts <tt>value</tt> to type
+<tt>ty2</tt>. It is always a <i>no-op cast</i> because no bits change with
+this conversion. The conversion is done as if the <tt>value</tt> had been
+stored to memory and read back as type <tt>ty2</tt>. Pointer types may only be
+converted to other pointer types with this instruction. To convert pointers to
+other types, use the <a href="#i_inttoptr">inttoptr</a> or
+<a href="#i_ptrtoint">ptrtoint</a> instructions first.</p>
+
+<h5>Example:</h5>
+<pre>
+ %X = bitcast i8 255 to i8 <i>; yields i8 :-1</i>
+ %Y = bitcast i32* %x to sint* <i>; yields sint*:%x</i>
+ %Z = bitcast <2xint> %V to i64; <i>; yields i64: %V</i>
+</pre>
+</div>
+
+<!-- ======================================================================= -->
+<div class="doc_subsection"> <a name="otherops">Other Operations</a> </div>
+<div class="doc_text">
+<p>The instructions in this category are the "miscellaneous"
+instructions, which defy better classification.</p>
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection"><a name="i_icmp">'<tt>icmp</tt>' Instruction</a>
+</div>
+<div class="doc_text">
+<h5>Syntax:</h5>
+<pre> <result> = icmp <cond> <ty> <var1>, <var2> <i>; yields {bool}:result</i>
+</pre>
+<h5>Overview:</h5>
+<p>The '<tt>icmp</tt>' instruction returns a boolean value based on comparison
+of its two integer operands.</p>
+<h5>Arguments:</h5>
+<p>The '<tt>icmp</tt>' instruction takes three operands. The first operand is
+the condition code which indicates the kind of comparison to perform. It is not
+a value, just a keyword. The possibilities for the condition code are:
+<ol>
+ <li><tt>eq</tt>: equal</li>
+ <li><tt>ne</tt>: not equal </li>
+ <li><tt>ugt</tt>: unsigned greater than</li>
+ <li><tt>uge</tt>: unsigned greater or equal</li>
+ <li><tt>ult</tt>: unsigned less than</li>
+ <li><tt>ule</tt>: unsigned less or equal</li>
+ <li><tt>sgt</tt>: signed greater than</li>
+ <li><tt>sge</tt>: signed greater or equal</li>
+ <li><tt>slt</tt>: signed less than</li>
+ <li><tt>sle</tt>: signed less or equal</li>
+</ol>
+<p>The remaining two arguments must be <a href="#t_integral">integral</a> or
+<a href="#t_pointer">pointer</a> typed. They must also be identical types.</p>
+<h5>Semantics:</h5>
+<p>The '<tt>icmp</tt>' compares <tt>var1</tt> and <tt>var2</tt> according to
+the condition code given as <tt>cond</tt>. The comparison performed always
+yields a <a href="#t_bool">bool</a> result, as follows:
+<ol>
+ <li><tt>eq</tt>: yields <tt>true</tt> if the operands are equal,
+ <tt>false</tt> otherwise. No sign interpretation is necessary or performed.
+ </li>
+ <li><tt>ne</tt>: yields <tt>true</tt> if the operands are unequal,
+ <tt>false</tt> otherwise. No sign interpretation is necessary or performed.
+ <li><tt>ugt</tt>: interprets the operands as unsigned values and yields
+ <tt>true</tt> if <tt>var1</tt> is greater than <tt>var2</tt>.</li>
+ <li><tt>uge</tt>: interprets the operands as unsigned values and yields
+ <tt>true</tt> if <tt>var1</tt> is greater than or equal to <tt>var2</tt>.</li>
+ <li><tt>ult</tt>: interprets the operands as unsigned values and yields
+ <tt>true</tt> if <tt>var1</tt> is less than <tt>var2</tt>.</li>
+ <li><tt>ule</tt>: interprets the operands as unsigned values and yields
+ <tt>true</tt> if <tt>var1</tt> is less than or equal to <tt>var2</tt>.</li>
+ <li><tt>sgt</tt>: interprets the operands as signed values and yields
+ <tt>true</tt> if <tt>var1</tt> is greater than <tt>var2</tt>.</li>
+ <li><tt>sge</tt>: interprets the operands as signed values and yields
+ <tt>true</tt> if <tt>var1</tt> is greater than or equal to <tt>var2</tt>.</li>
+ <li><tt>slt</tt>: interprets the operands as signed values and yields
+ <tt>true</tt> if <tt>var1</tt> is less than <tt>var2</tt>.</li>
+ <li><tt>sle</tt>: interprets the operands as signed values and yields
+ <tt>true</tt> if <tt>var1</tt> is less than or equal to <tt>var2</tt>.</li>
+ </li>
+</ol>
+<p>If the operands are <a href="#t_pointer">pointer</a> typed, the pointer
+values are treated as integers and then compared.</p>
+<p>If the operands are <a href="#t_packed">packed</a> typed, the elements of
+the vector are compared in turn and the predicate must hold for all
+elements.</p>
+
+<h5>Example:</h5>
+<pre> <result> = icmp eq i32 4, 5 <i>; yields: result=false</i>
+ <result> = icmp ne float* %X, %X <i>; yields: result=false</i>
+ <result> = icmp ult i16 4, 5 <i>; yields: result=true</i>
+ <result> = icmp sgt i16 4, 5 <i>; yields: result=false</i>
+ <result> = icmp ule i16 -4, 5 <i>; yields: result=false</i>
+ <result> = icmp sge i16 4, 5 <i>; yields: result=false</i>
+</pre>
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection"><a name="i_fcmp">'<tt>fcmp</tt>' Instruction</a>
+</div>
+<div class="doc_text">
+<h5>Syntax:</h5>
+<pre> <result> = fcmp <cond> <ty> <var1>, <var2> <i>; yields {bool}:result</i>
+</pre>
+<h5>Overview:</h5>
+<p>The '<tt>fcmp</tt>' instruction returns a boolean value based on comparison
+of its floating point operands.</p>
+<h5>Arguments:</h5>
+<p>The '<tt>fcmp</tt>' instruction takes three operands. The first operand is
+the condition code which indicates the kind of comparison to perform. It is not
+a value, just a keyword. The possibilities for the condition code are:
+<ol>
+ <li><tt>false</tt>: no comparison, always returns false</li>
+ <li><tt>oeq</tt>: ordered and equal</li>
+ <li><tt>ogt</tt>: ordered and greater than </li>
+ <li><tt>oge</tt>: ordered and greater than or equal</li>
+ <li><tt>olt</tt>: ordered and less than </li>
+ <li><tt>ole</tt>: ordered and less than or equal</li>
+ <li><tt>one</tt>: ordered and not equal</li>
+ <li><tt>ord</tt>: ordered (no nans)</li>
+ <li><tt>ueq</tt>: unordered or equal</li>
+ <li><tt>ugt</tt>: unordered or greater than </li>
+ <li><tt>uge</tt>: unordered or greater than or equal</li>
+ <li><tt>ult</tt>: unordered or less than </li>
+ <li><tt>ule</tt>: unordered or less than or equal</li>
+ <li><tt>une</tt>: unordered or not equal</li>
+ <li><tt>uno</tt>: unordered (either nans)</li>
+ <li><tt>true</tt>: no comparison, always returns true</li>
+</ol>
+<p>In the preceding, <i>ordered</i> means that neither operand is a QNAN while
+<i>unordered</i> means that either operand may be a QNAN.</p>
+<p>The <tt>val1</tt> and <tt>val2</tt> arguments must be
+<a href="#t_floating">floating point</a> typed. They must have identical
+types.</p>
+<p>In the foregoing, <i>ordered</i> means that neither operand is a QNAN and
+<i>unordered</i> means that either operand is a QNAN.</p>
+<h5>Semantics:</h5>
+<p>The '<tt>fcmp</tt>' compares <tt>var1</tt> and <tt>var2</tt> according to
+the condition code given as <tt>cond</tt>. The comparison performed always
+yields a <a href="#t_bool">bool</a> result, as follows:
+<ol>
+ <li><tt>false</tt>: always yields <tt>false</tt>, regardless of operands.</li>
+ <li><tt>oeq</tt>: yields <tt>true</tt> if both operands are not a QNAN and
+ <tt>var1</tt> is equal to <tt>var2</tt>.</li>
+ <li><tt>ogt</tt>: yields <tt>true</tt> if both operands are not a QNAN and
+ <tt>var1</tt> is greather than <tt>var2</tt>.</li>
+ <li><tt>oge</tt>: yields <tt>true</tt> if both operands are not a QNAN and
+ <tt>var1</tt> is greater than or equal to <tt>var2</tt>.</li>
+ <li><tt>olt</tt>: yields <tt>true</tt> if both operands are not a QNAN and
+ <tt>var1</tt> is less than <tt>var2</tt>.</li>
+ <li><tt>ole</tt>: yields <tt>true</tt> if both operands are not a QNAN and
+ <tt>var1</tt> is less than or equal to <tt>var2</tt>.</li>
+ <li><tt>one</tt>: yields <tt>true</tt> if both operands are not a QNAN and
+ <tt>var1</tt> is not equal to <tt>var2</tt>.</li>
+ <li><tt>ord</tt>: yields <tt>true</tt> if both operands are not a QNAN.</li>
+ <li><tt>ueq</tt>: yields <tt>true</tt> if either operand is a QNAN or
+ <tt>var1</tt> is equal to <tt>var2</tt>.</li>
+ <li><tt>ugt</tt>: yields <tt>true</tt> if either operand is a QNAN or
+ <tt>var1</tt> is greater than <tt>var2</tt>.</li>
+ <li><tt>uge</tt>: yields <tt>true</tt> if either operand is a QNAN or
+ <tt>var1</tt> is greater than or equal to <tt>var2</tt>.</li>
+ <li><tt>ult</tt>: yields <tt>true</tt> if either operand is a QNAN or
+ <tt>var1</tt> is less than <tt>var2</tt>.</li>
+ <li><tt>ule</tt>: yields <tt>true</tt> if either operand is a QNAN or
+ <tt>var1</tt> is less than or equal to <tt>var2</tt>.</li>
+ <li><tt>une</tt>: yields <tt>true</tt> if either operand is a QNAN or
+ <tt>var1</tt> is not equal to <tt>var2</tt>.</li>
+ <li><tt>uno</tt>: yields <tt>true</tt> if either operand is a QNAN.</li>
+ <li><tt>true</tt>: always yields <tt>true</tt>, regardless of operands.</li>
+</ol>
+<p>If the operands are <a href="#t_packed">packed</a> typed, the elements of
+the vector are compared in turn and the predicate must hold for all elements.
</p>
<h5>Example:</h5>
-
-<pre>
- %X = cast int 257 to ubyte <i>; yields ubyte:1</i>
- %Y = cast int 123 to bool <i>; yields bool:true</i>
+<pre> <result> = fcmp oeq float 4.0, 5.0 <i>; yields: result=false</i>
+ <result> = icmp one float 4.0, 5.0 <i>; yields: result=true</i>
+ <result> = icmp olt float 4.0, 5.0 <i>; yields: result=true</i>
+ <result> = icmp ueq double 1.0, 2.0 <i>; yields: result=false</i>
</pre>
</div>
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection"> <a name="i_phi">'<tt>phi</tt>'
+Instruction</a> </div>
+<div class="doc_text">
+<h5>Syntax:</h5>
+<pre> <result> = phi <ty> [ <val0>, <label0>], ...<br></pre>
+<h5>Overview:</h5>
+<p>The '<tt>phi</tt>' instruction is used to implement the φ node in
+the SSA graph representing the function.</p>
+<h5>Arguments:</h5>
+<p>The type of the incoming values are specified with the first type
+field. After this, the '<tt>phi</tt>' instruction takes a list of pairs
+as arguments, with one pair for each predecessor basic block of the
+current block. Only values of <a href="#t_firstclass">first class</a>
+type may be used as the value arguments to the PHI node. Only labels
+may be used as the label arguments.</p>
+<p>There must be no non-phi instructions between the start of a basic
+block and the PHI instructions: i.e. PHI instructions must be first in
+a basic block.</p>
+<h5>Semantics:</h5>
+<p>At runtime, the '<tt>phi</tt>' instruction logically takes on the
+value specified by the parameter, depending on which basic block we
+came from in the last <a href="#terminators">terminator</a> instruction.</p>
+<h5>Example:</h5>
+<pre>Loop: ; Infinite loop that counts from 0 on up...<br> %indvar = phi i32 [ 0, %LoopHeader ], [ %nextindvar, %Loop ]<br> %nextindvar = add i32 %indvar, 1<br> br label %Loop<br></pre>
+</div>
+
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
<a name="i_select">'<tt>select</tt>' Instruction</a>
<p>
If the boolean condition evaluates to true, the instruction returns the first
-value argument, otherwise it returns the second value argument.
+value argument; otherwise, it returns the second value argument.
</p>
<h5>Example:</h5>
<pre>
- %X = select bool true, ubyte 17, ubyte 42 <i>; yields ubyte:17</i>
+ %X = select bool true, i8 17, i8 42 <i>; yields i8:17</i>
</pre>
</div>
-
-
-
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
<a name="i_call">'<tt>call</tt>' Instruction</a>
<li>
<p>'<tt>ty</tt>': shall be the signature of the pointer to function value
being invoked. The argument types must match the types implied by this
- signature.</p>
+ signature. This type can be omitted if the function is not varargs and
+ if the function type does not return a pointer to a function.</p>
</li>
<li>
<p>'<tt>fnptrval</tt>': An LLVM value containing a pointer to a function to
be invoked. In most cases, this is a direct function invocation, but
indirect <tt>call</tt>s are just as possible, calling an arbitrary pointer
- to function values.</p>
+ to function value.</p>
</li>
<li>
<p>'<tt>function args</tt>': argument list whose types match the
<h5>Example:</h5>
<pre>
- %retval = call int %test(int %argc)
- call int(sbyte*, ...) *%printf(sbyte* %msg, int 12, sbyte 42);
- %X = tail call int %foo()
- %Y = tail call <a href="#callingconv">fastcc</a> int %foo()
-</pre>
-
-</div>
-
-<!-- _______________________________________________________________________ -->
-<div class="doc_subsubsection">
- <a name="i_vanext">'<tt>vanext</tt>' Instruction</a>
-</div>
-
-<div class="doc_text">
-
-<h5>Syntax:</h5>
-
-<pre>
- <resultarglist> = vanext <va_list> <arglist>, <argty>
+ %retval = call i32 %test(i32 %argc)
+ call i32(i8 *, ...) *%printf(i8 * %msg, i32 12, i8 42);
+ %X = tail call i32 %foo()
+ %Y = tail call <a href="#callingconv">fastcc</a> i32 %foo()
</pre>
-<h5>Overview:</h5>
-
-<p>The '<tt>vanext</tt>' instruction is used to access arguments passed
-through the "variable argument" area of a function call. It is used to
-implement the <tt>va_arg</tt> macro in C.</p>
-
-<h5>Arguments:</h5>
-
-<p>This instruction takes a <tt>va_list</tt> value and the type of the
-argument. It returns another <tt>va_list</tt>. The actual type of
-<tt>va_list</tt> may be defined differently for different targets. Most targets
-use a <tt>va_list</tt> type of <tt>sbyte*</tt> or some other pointer type.</p>
-
-<h5>Semantics:</h5>
-
-<p>The '<tt>vanext</tt>' instruction advances the specified <tt>va_list</tt>
-past an argument of the specified type. In conjunction with the <a
- href="#i_vaarg"><tt>vaarg</tt></a> instruction, it is used to implement
-the <tt>va_arg</tt> macro available in C. For more information, see
-the variable argument handling <a href="#int_varargs">Intrinsic
-Functions</a>.</p>
-
-<p>It is legal for this instruction to be called in a function which
-does not take a variable number of arguments, for example, the <tt>vfprintf</tt>
-function.</p>
-
-<p><tt>vanext</tt> is an LLVM instruction instead of an <a
-href="#intrinsics">intrinsic function</a> because it takes a type as an
-argument. The type refers to the current argument in the <tt>va_list</tt>, it
-tells the compiler how far on the stack it needs to advance to find the next
-argument</p>
-
-<h5>Example:</h5>
-
-<p>See the <a href="#int_varargs">variable argument processing</a>
-section.</p>
-
</div>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_vaarg">'<tt>vaarg</tt>' Instruction</a>
+ <a name="i_va_arg">'<tt>va_arg</tt>' Instruction</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- <resultval> = vaarg <va_list> <arglist>, <argty>
+ <resultval> = va_arg <va_list*> <arglist>, <argty>
</pre>
<h5>Overview:</h5>
-<p>The '<tt>vaarg</tt>' instruction is used to access arguments passed through
+<p>The '<tt>va_arg</tt>' instruction is used to access arguments passed through
the "variable argument" area of a function call. It is used to implement the
<tt>va_arg</tt> macro in C.</p>
<h5>Arguments:</h5>
-<p>This instruction takes a <tt>va_list</tt> value and the type of the
-argument. It returns a value of the specified argument type. Again, the actual
-type of <tt>va_list</tt> is target specific.</p>
+<p>This instruction takes a <tt>va_list*</tt> value and the type of
+the argument. It returns a value of the specified argument type and
+increments the <tt>va_list</tt> to point to the next argument. Again, the
+actual type of <tt>va_list</tt> is target specific.</p>
<h5>Semantics:</h5>
-<p>The '<tt>vaarg</tt>' instruction loads an argument of the specified type from
-the specified <tt>va_list</tt>. In conjunction with the <a
-href="#i_vanext"><tt>vanext</tt></a> instruction, it is used to implement the
-<tt>va_arg</tt> macro available in C. For more information, see the variable
-argument handling <a href="#int_varargs">Intrinsic Functions</a>.</p>
+<p>The '<tt>va_arg</tt>' instruction loads an argument of the specified
+type from the specified <tt>va_list</tt> and causes the
+<tt>va_list</tt> to point to the next argument. For more information,
+see the variable argument handling <a href="#int_varargs">Intrinsic
+Functions</a>.</p>
<p>It is legal for this instruction to be called in a function which does not
take a variable number of arguments, for example, the <tt>vfprintf</tt>
function.</p>
-<p><tt>vaarg</tt> is an LLVM instruction instead of an <a
-href="#intrinsics">intrinsic function</a> because it takes an type as an
+<p><tt>va
_arg</tt> is an LLVM instruction instead of an <a
+href="#intrinsics">intrinsic function</a> because it takes a type as an
argument.</p>
<h5>Example:</h5>
<div class="doc_text">
<p>LLVM supports the notion of an "intrinsic function". These functions have
-well known names and semantics, and are required to follow certain
+well known names and semantics and are required to follow certain
restrictions. Overall, these instructions represent an extension mechanism for
the LLVM language that does not require changing all of the transformations in
LLVM to add to the language (or the bytecode reader/writer, the parser,
etc...).</p>
-<p>Intrinsic function names must all start with an "<tt>llvm.</tt>" prefix, this
-prefix is reserved in LLVM for intrinsic names, thus functions may not be named
+<p>Intrinsic function names must all start with an "<tt>llvm.</tt>" prefix. This
+prefix is reserved in LLVM for intrinsic names; thus, functions may not be named
this. Intrinsic functions must always be external functions: you cannot define
the body of intrinsic functions. Intrinsic functions may only be used in call
or invoke instructions: it is illegal to take the address of an intrinsic
language, it is required that they all be documented here if any are added.</p>
-<p>To learn how to add an intrinsic
s, please see the <a
+<p>To learn how to add an intrinsic
function, please see the <a
href="ExtendingLLVM.html">Extending LLVM Guide</a>.
</p>
<div class="doc_text">
<p>Variable argument support is defined in LLVM with the <a
- href="#i_vanext"><tt>vanext</tt></a> instruction and these three
+ href="#i_va_arg"><tt>va_arg</tt></a> instruction and these three
intrinsic functions. These functions are related to the similarly
named macros defined in the <tt><stdarg.h></tt> header file.</p>
transformations should be prepared to handle intrinsics with any type
used.</p>
-<p>This example shows how the <a href="#i_vanext"><tt>vanext</tt></a>
+<p>This example shows how the <a href="#i_va_arg"><tt>va_arg</tt></a>
instruction and the variable argument handling intrinsic functions are
used.</p>
<pre>
-int %test(int %X, ...) {
+define i32 %test(i32 %X, ...) {
; Initialize variable argument processing
- %ap = call sbyte* %<a href="#i_va_start">llvm.va_start</a>()
+ %ap = alloca i8 *
+ call void %<a href="#i_va_start">llvm.va_start</a>(i8 ** %ap)
; Read a single integer argument
- %tmp = vaarg sbyte* %ap, int
-
- ; Advance to the next argument
- %ap2 = vanext sbyte* %ap, int
+ %tmp = va_arg i8 ** %ap, i32
; Demonstrate usage of llvm.va_copy and llvm.va_end
- %aq = call sbyte* %<a href="#i_va_copy">llvm.va_copy</a>(sbyte* %ap2)
- call void %<a href="#i_va_end">llvm.va_end</a>(sbyte* %aq)
+ %aq = alloca i8 *
+ call void %<a href="#i_va_copy">llvm.va_copy</a>(i8 ** %aq, i8 ** %ap)
+ call void %<a href="#i_va_end">llvm.va_end</a>(i8 ** %aq)
; Stop processing of arguments.
- call void %<a href="#i_va_end">llvm.va_end</a>(sbyte* %ap2)
- ret int %tmp
+ call void %<a href="#i_va_end">llvm.va_end</a>(i8 ** %ap)
+ ret i32 %tmp
}
</pre>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
-<pre> declare <va_list> %llvm.va_start()<br></pre>
+<pre> declare void %llvm.va_start(<va_list>* <arglist>)<br></pre>
<h5>Overview:</h5>
-<p>The '<tt>llvm.va_start</tt>' intrinsic returns a new <tt><arglist></tt>
-for subsequent use by the variable argument intrinsics.</p>
+<P>The '<tt>llvm.va_start</tt>' intrinsic initializes
+<tt>*<arglist></tt> for subsequent use by <tt><a
+href="#i_va_arg">va_arg</a></tt>.</p>
+
+<h5>Arguments:</h5>
+
+<P>The argument is a pointer to a <tt>va_list</tt> element to initialize.</p>
+
<h5>Semantics:</h5>
-<p>The '<tt>llvm.va_start</tt>' intrinsic works just like the <tt>va_start</tt>
-macro available in C. In a target-dependent way, it initializes and
-returns a <tt>va_list</tt> element, so that the next <tt>vaarg</tt>
-will produce the first variable argument passed to the function. Unlike
-the C <tt>va_start</tt> macro, this intrinsic does not need to know the
+
+<P>The '<tt>llvm.va_start</tt>' intrinsic works just like the <tt>va_start</tt>
+macro available in C. In a target-dependent way, it initializes the
+<tt>va_list</tt> element the argument points to, so that the next call to
+<tt>va_arg</tt> will produce the first variable argument passed to the function.
+Unlike the C <tt>va_start</tt> macro, this intrinsic does not need to know the
last argument of the function, the compiler can figure that out.</p>
-<p>Note that this intrinsic function is only legal to be called from
-within the body of a variable argument function.</p>
+
</div>
<!-- _______________________________________________________________________ -->
<div class="doc_text">
<h5>Syntax:</h5>
-<pre> declare void %llvm.va_end(<va_list> <arglist>)<br></pre>
+<pre> declare void %llvm.va_end(<va_list*> <arglist>)<br></pre>
<h5>Overview:</h5>
<p>The '<tt>llvm.va_end</tt>' intrinsic destroys <tt><arglist></tt>
which has been initialized previously with <tt><a href="#i_va_start">llvm.va_start</a></tt>
<h5>Syntax:</h5>
<pre>
- declare <va_list> %llvm.va_copy(<va_list> <destarglist>)
+ declare void %llvm.va_copy(<va_list>* <destarglist>,
+ <va_list>* <srcarglist>)
</pre>
<h5>Overview:</h5>
-<p>The '<tt>llvm.va_copy</tt>' intrinsic copies the current argument position
-from the source argument list to the destination argument list.</p>
+<p>The '<tt>llvm.va_copy</tt>' intrinsic copies the current argument position from
+the source argument list to the destination argument list.</p>
<h5>Arguments:</h5>
-<p>The argument is the <tt>va_list</tt> to copy.</p>
+<p>The first argument is a pointer to a <tt>va_list</tt> element to initialize.
+The second argument is a pointer to a <tt>va_list</tt> element to copy from.</p>
+
<h5>Semantics:</h5>
-<p>The '<tt>llvm.va_copy</tt>' intrinsic works just like the <tt>va_copy</tt>
-macro available in C. In a target-dependent way, it copies the source
-<tt>va_list</tt> element into the returned list. This intrinsic is necessary
-because the <tt><a href="#i_va_start">llvm.va_start</a></tt> intrinsic may be
+<p>The '<tt>llvm.va_copy</tt>' intrinsic works just like the <tt>va_copy</tt> macro
+available in C. In a target-dependent way, it copies the source
+<tt>va_list</tt> element into the destination list. This intrinsic is necessary
+because the <tt><a href="i_va_begin">llvm.va_begin</a></tt> intrinsic may be
arbitrarily complex and require memory allocation, for example.</p>
</div>
<h5>Syntax:</h5>
<pre>
- declare sbyte* %llvm.gcread(sbyte** %Ptr)
+ declare i8 * %llvm.gcread(i8 * %ObjPtr, i8 ** %Ptr)
</pre>
<h5>Overview:</h5>
<h5>Arguments:</h5>
-<p>The argument is the address to read from, which should be an address
-allocated from the garbage collector.</p>
+<p>The second argument is the address to read from, which should be an address
+allocated from the garbage collector. The first object is a pointer to the
+start of the referenced object, if needed by the language runtime (otherwise
+null).</p>
<h5>Semantics:</h5>
<h5>Syntax:</h5>
<pre>
- declare void %llvm.gcwrite(sbyte* %P1, sbyte** %P2)
+ declare void %llvm.gcwrite(i8 * %P1, i8 * %Obj, i8 ** %P2)
</pre>
<h5>Overview:</h5>
<h5>Arguments:</h5>
-<p>The first argument is the reference to store, and the second is the heap
-location to store to.</p>
+<p>The first argument is the reference to store, the second is the start of the
+object to store it to, and the third is the address of the field of Obj to
+store to. If the runtime does not require a pointer to the object, Obj may be
+null.</p>
<h5>Semantics:</h5>
<h5>Syntax:</h5>
<pre>
- declare void* %llvm.returnaddress(uint <level>)
+ declare i8 *%llvm.returnaddress(i32 <level>)
</pre>
<h5>Overview:</h5>
<p>
-The '<tt>llvm.returnaddress</tt>' intrinsic returns a target-specific value
-indicating the return address of the current function or one of its callers.
+The '<tt>llvm.returnaddress</tt>' intrinsic attempts to compute a
+target-specific value indicating the return address of the current function
+or one of its callers.
</p>
<h5>Arguments:</h5>
<h5>Syntax:</h5>
<pre>
- declare void* %llvm.frameaddress(uint <level>)
+ declare i8 *%llvm.frameaddress(i32 <level>)
</pre>
<h5>Overview:</h5>
<p>
-The '<tt>llvm.frameaddress</tt>' intrinsic returns the target-specific frame
-pointer value for the specified stack frame.
+The '<tt>llvm.frameaddress</tt>' intrinsic attempts to return the
+target-specific frame pointer value for the specified stack frame.
</p>
<h5>Arguments:</h5>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_prefetch">'<tt>llvm.prefetch</tt>' Intrinsic</a>
+ <a name="i_stacksave">'<tt>llvm.stacksave</tt>' Intrinsic</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- declare void %llvm.prefetch(sbyte * <address>,
- uint <rw>, uint <locality>)
+ declare i8 *%llvm.stacksave()
</pre>
<h5>Overview:</h5>
-
-<p>
-The '<tt>llvm.prefetch</tt>' intrinsic is a hint to the code generator to insert
-a prefetch instruction if supported, otherwise it is a noop. Prefetches have no
-effect on the behavior of the program, but can change its performance
-characteristics.
-</p>
-
-<h5>Arguments:</h5>
-
<p>
-<tt>address</tt> is the address to be prefetched, <tt>rw</tt> is the specifier
-determining if the fetch should be for a read (0) or write (1), and
-<tt>locality</tt> is a temporal locality specifier ranging from (0) - no
-locality, to (3) - extremely local keep in cache. The <tt>rw</tt> and
-<tt>locality</tt> arguments must be constant integers.
+The '<tt>llvm.stacksave</tt>' intrinsic is used to remember the current state of
+the function stack, for use with <a href="#i_stackrestore">
+<tt>llvm.stackrestore</tt></a>. This is useful for implementing language
+features like scoped automatic variable sized arrays in C99.
</p>
<h5>Semantics:</h5>
<p>
-This intrinsic does not modify the behavior of the program. In particular,
-prefetches cannot trap and do not produce a value. On targets that support this
-intrinsic, the prefetch can provide hints to the processor cache for better
-performance.
+This intrinsic returns a opaque pointer value that can be passed to <a
+href="#i_stackrestore"><tt>llvm.stackrestore</tt></a>. When an
+<tt>llvm.stackrestore</tt> intrinsic is executed with a value saved from
+<tt>llvm.stacksave</tt>, it effectively restores the state of the stack to the
+state it was in when the <tt>llvm.stacksave</tt> intrinsic executed. In
+practice, this pops any <a href="#i_alloca">alloca</a> blocks from the stack
+that were allocated after the <tt>llvm.stacksave</tt> was executed.
</p>
</div>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_pcmarker">'<tt>llvm.pcmarker</tt>' Intrinsic</a>
+ <a name="i_stackrestore">'<tt>llvm.stackrestore</tt>' Intrinsic</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- declare void %llvm.pcmarker( uint <id> )
+ declare void %llvm.stackrestore(i8 * %ptr)
</pre>
<h5>Overview:</h5>
-
-<p>
-The '<tt>llvm.pcmarker</tt>' intrinsic is a method to export a PC in a region of
-code to simulators and other tools. The method is target specific, but it is
-expected that the marker will use exported symbols to transmit the PC of the marker.
-The marker makes no guaranties that it will remain with any specific instruction
-after optimizations. It is possible that the presense of a marker will inhibit
-optimizations. The intended use is to be inserted after optmizations to allow
-corrolations of simulation runs.
-</p>
-
-<h5>Arguments:</h5>
-
<p>
-<tt>id</tt> is a numerical id identifying the marker.
+The '<tt>llvm.stackrestore</tt>' intrinsic is used to restore the state of
+the function stack to the state it was in when the corresponding <a
+href="#llvm.stacksave"><tt>llvm.stacksave</tt></a> intrinsic executed. This is
+useful for implementing language features like scoped automatic variable sized
+arrays in C99.
</p>
<h5>Semantics:</h5>
<p>
-This intrinsic does not modify the behavior of the program. Backends that do not
-support this intrinisic may ignore it.
+See the description for <a href="#i_stacksave"><tt>llvm.stacksave</tt></a>.
</p>
</div>
-<!-- ======================================================================= -->
-<div class="doc_subsection">
- <a name="int_os">Operating System Intrinsics</a>
-</div>
-
-<div class="doc_text">
-<p>
-These intrinsics are provided by LLVM to support the implementation of
-operating system level code.
-</p>
-
-</div>
-
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_readport">'<tt>llvm.readport</tt>' Intrinsic</a>
+ <a name="i_prefetch">'<tt>llvm.prefetch</tt>' Intrinsic</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- declare <integer type> %llvm.readport (<integer type> <address>)
+ declare void %llvm.prefetch(i8 * <address>,
+ i32 <rw>, i32 <locality>)
</pre>
<h5>Overview:</h5>
-<p>
-The '<tt>llvm.readport</tt>' intrinsic reads data from the specified hardware
-I/O port.
-</p>
-
-<h5>Arguments:</h5>
-
-<p>
-The argument to this intrinsic indicates the hardware I/O address from which
-to read the data. The address is in the hardware I/O address namespace (as
-opposed to being a memory location for memory mapped I/O).
-</p>
-
-<h5>Semantics:</h5>
-
-<p>
-The '<tt>llvm.readport</tt>' intrinsic reads data from the hardware I/O port
-specified by <i>address</i> and returns the value. The address and return
-value must be integers, but the size is dependent upon the platform upon which
-the program is code generated. For example, on x86, the address must be an
-unsigned 16-bit value, and the return value must be 8, 16, or 32 bits.
-</p>
-
-</div>
-
-<!-- _______________________________________________________________________ -->
-<div class="doc_subsubsection">
- <a name="i_writeport">'<tt>llvm.writeport</tt>' Intrinsic</a>
-</div>
-
-<div class="doc_text">
-
-<h5>Syntax:</h5>
-<pre>
- call void (<integer type>, <integer type>)*
- %llvm.writeport (<integer type> <value>,
- <integer type> <address>)
-</pre>
-
-<h5>Overview:</h5>
<p>
-The '<tt>llvm.writeport</tt>' intrinsic writes data to the specified hardware
-I/O port.
+The '<tt>llvm.prefetch</tt>' intrinsic is a hint to the code generator to insert
+a prefetch instruction if supported; otherwise, it is a noop. Prefetches have
+no
+effect on the behavior of the program but can change its performance
+characteristics.
</p>
<h5>Arguments:</h5>
<p>
-The first argument is the value to write to the I/O port.
-</p>
-
-<p>
-The second argument indicates the hardware I/O address to which data should be
-written. The address is in the hardware I/O address namespace (as opposed to
-being a memory location for memory mapped I/O).
+<tt>address</tt> is the address to be prefetched, <tt>rw</tt> is the specifier
+determining if the fetch should be for a read (0) or write (1), and
+<tt>locality</tt> is a temporal locality specifier ranging from (0) - no
+locality, to (3) - extremely local keep in cache. The <tt>rw</tt> and
+<tt>locality</tt> arguments must be constant integers.
</p>
<h5>Semantics:</h5>
<p>
-The '<tt>llvm.writeport</tt>' intrinsic writes <i>value</i> to the I/O port
-specified by <i>address</i>. The address and value must be integers, but the
-size is dependent upon the platform upon which the program is code generated.
-For example, on x86, the address must be an unsigned 16-bit value, and the
-value written must be 8, 16, or 32 bits in length.
+This intrinsic does not modify the behavior of the program. In particular,
+prefetches cannot trap and do not produce a value. On targets that support this
+intrinsic, the prefetch can provide hints to the processor cache for better
+performance.
</p>
</div>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_readio">'<tt>llvm.readio</tt>' Intrinsic</a>
+ <a name="i_pcmarker">'<tt>llvm.pcmarker</tt>' Intrinsic</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- declare <result> %llvm.readio (<ty> * <pointer>)
+ declare void %llvm.pcmarker( i32 <id> )
</pre>
<h5>Overview:</h5>
+
<p>
-The '<tt>llvm.readio</tt>' intrinsic reads data from a memory mapped I/O
-address.
+The '<tt>llvm.pcmarker</tt>' intrinsic is a method to export a Program Counter
+(PC) in a region of
+code to simulators and other tools. The method is target specific, but it is
+expected that the marker will use exported symbols to transmit the PC of the marker.
+The marker makes no guarantees that it will remain with any specific instruction
+after optimizations. It is possible that the presence of a marker will inhibit
+optimizations. The intended use is to be inserted after optimizations to allow
+correlations of simulation runs.
</p>
<h5>Arguments:</h5>
<p>
-The argument to this intrinsic is a pointer indicating the memory address from
-which to read the data. The data must be a
-<a href="#t_firstclass">first class</a> type.
+<tt>id</tt> is a numerical id identifying the marker.
</p>
<h5>Semantics:</h5>
<p>
-The '<tt>llvm.readio</tt>' intrinsic reads data from a memory mapped I/O
-location specified by <i>pointer</i> and returns the value. The argument must
-be a pointer, and the return value must be a
-<a href="#t_firstclass">first class</a> type. However, certain architectures
-may not support I/O on all first class types. For example, 32-bit processors
-may only support I/O on data types that are 32 bits or less.
-</p>
-
-<p>
-This intrinsic enforces an in-order memory model for llvm.readio and
-llvm.writeio calls on machines that use dynamic scheduling. Dynamically
-scheduled processors may execute loads and stores out of order, re-ordering at
-run time accesses to memory mapped I/O registers. Using these intrinsics
-ensures that accesses to memory mapped I/O registers occur in program order.
+This intrinsic does not modify the behavior of the program. Backends that do not
+support this intrinisic may ignore it.
</p>
</div>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_writeio">'<tt>llvm.writeio</tt>' Intrinsic</a>
+ <a name="i_readcyclecounter">'<tt>llvm.readcyclecounter</tt>' Intrinsic</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- declare void %llvm.writeio (<ty1> <value>, <ty2> * <pointer>)
+ declare i64 %llvm.readcyclecounter( )
</pre>
<h5>Overview:</h5>
-<p>
-The '<tt>llvm.writeio</tt>' intrinsic writes data to the specified memory
-mapped I/O address.
-</p>
-
-<h5>Arguments:</h5>
<p>
-The first argument is the value to write to the memory mapped I/O location.
-The second argument is a pointer indicating the memory address to which the
-data should be written.
+The '<tt>llvm.readcyclecounter</tt>' intrinsic provides access to the cycle
+counter register (or similar low latency, high accuracy clocks) on those targets
+that support it. On X86, it should map to RDTSC. On Alpha, it should map to RPCC.
+As the backing counters overflow quickly (on the order of 9 seconds on alpha), this
+should only be used for small timings.
</p>
<h5>Semantics:</h5>
<p>
-The '<tt>llvm.writeio</tt>' intrinsic writes <i>value</i> to the memory mapped
-I/O address specified by <i>pointer</i>. The value must be a
-<a href="#t_firstclass">first class</a> type. However, certain architectures
-may not support I/O on all first class types. For example, 32-bit processors
-may only support I/O on data types that are 32 bits or less.
-</p>
-
-<p>
-This intrinsic enforces an in-order memory model for llvm.readio and
-llvm.writeio calls on machines that use dynamic scheduling. Dynamically
-scheduled processors may execute loads and stores out of order, re-ordering at
-run time accesses to memory mapped I/O registers. Using these intrinsics
-ensures that accesses to memory mapped I/O registers occur in program order.
+When directly supported, reading the cycle counter should not modify any memory.
+Implementations are allowed to either return a application specific value or a
+system wide value. On backends without support, this is lowered to a constant 0.
</p>
</div>
<h5>Syntax:</h5>
<pre>
- declare void %llvm.memcpy(sbyte* <dest>, sbyte* <src>,
- uint <len>, uint <align>)
+ declare void %llvm.memcpy.i32(i8 * <dest>, i8 * <src>,
+ i32 <len>, i32 <align>)
+ declare void %llvm.memcpy.i64(i8 * <dest>, i8 * <src>,
+ i64 <len>, i32 <align>)
</pre>
<h5>Overview:</h5>
<p>
-The '<tt>llvm.memcpy</tt>' intrinsic copies a block of memory from the source
+The '<tt>llvm.memcpy.*</tt>' intrinsics copy a block of memory from the source
location to the destination location.
</p>
<p>
-Note that, unlike the standard libc function, the <tt>llvm.memcpy</tt> intrinsic
-does not return a value, and takes an extra alignment argument.
+Note that, unlike the standard libc function, the <tt>llvm.memcpy.*</tt>
+intrinsics do not return a value, and takes an extra alignment argument.
</p>
<h5>Arguments:</h5>
<p>
The first argument is a pointer to the destination, the second is a pointer to
-the source. The third argument is an (arbitrarily sized) integer argument
+the source. The third argument is an integer argument
specifying the number of bytes to copy, and the fourth argument is the alignment
of the source and destination locations.
</p>
<p>
If the call to this intrinisic has an alignment value that is not 0 or 1, then
-the caller guarantees that the size of the copy is a multiple of the alignment
-and that both the source and destination pointers are aligned to that boundary.
+the caller guarantees that both the source and destination pointers are aligned
+to that boundary.
</p>
<h5>Semantics:</h5>
<p>
-The '<tt>llvm.memcpy</tt>' intrinsic copies a block of memory from the source
+The '<tt>llvm.memcpy.*</tt>' intrinsics copy a block of memory from the source
location to the destination location, which are not allowed to overlap. It
copies "len" bytes of memory over. If the argument is known to be aligned to
some boundary, this can be specified as the fourth argument, otherwise it should
<h5>Syntax:</h5>
<pre>
- declare void %llvm.memmove(sbyte* <dest>, sbyte* <src>,
- uint <len>, uint <align>)
+ declare void %llvm.memmove.i32(i8 * <dest>, i8 * <src>,
+ i32 <len>, i32 <align>)
+ declare void %llvm.memmove.i64(i8 * <dest>, i8 * <src>,
+ i64 <len>, i32 <align>)
</pre>
<h5>Overview:</h5>
<p>
-The '<tt>llvm.memmove</tt>' intrinsic moves a block of memory from the source
-location to the destination location. It is similar to the '<tt>llvm.memcpy</tt>'
-intrinsic but allows the two memory locations to overlap.
+The '<tt>llvm.memmove.*</tt>' intrinsics move a block of memory from the source
+location to the destination location. It is similar to the
+'<tt>llvm.memcmp</tt>' intrinsic but allows the two memory locations to overlap.
</p>
<p>
-Note that, unlike the standard libc function, the <tt>llvm.memmove</tt> intrinsic
-does not return a value, and takes an extra alignment argument.
+Note that, unlike the standard libc function, the <tt>llvm.memmove.*</tt>
+intrinsics do not return a value, and takes an extra alignment argument.
</p>
<h5>Arguments:</h5>
<p>
The first argument is a pointer to the destination, the second is a pointer to
-the source. The third argument is an (arbitrarily sized) integer argument
+the source. The third argument is an integer argument
specifying the number of bytes to copy, and the fourth argument is the alignment
of the source and destination locations.
</p>
<p>
If the call to this intrinisic has an alignment value that is not 0 or 1, then
-the caller guarantees that the size of the copy is a multiple of the alignment
-and that both the source and destination pointers are aligned to that boundary.
+the caller guarantees that the source and destination pointers are aligned to
+that boundary.
</p>
<h5>Semantics:</h5>
<p>
-The '<tt>llvm.memmove</tt>' intrinsic copies a block of memory from the source
+The '<tt>llvm.memmove.*</tt>' intrinsics copy a block of memory from the source
location to the destination location, which may overlap. It
copies "len" bytes of memory over. If the argument is known to be aligned to
some boundary, this can be specified as the fourth argument, otherwise it should
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_memset">'<tt>llvm.memset</tt>' Intrinsic</a>
+ <a name="i_memset">'<tt>llvm.memset.*</tt>' Intrinsics</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- declare void %llvm.memset(sbyte* <dest>, ubyte <val>,
- uint <len>, uint <align>)
+ declare void %llvm.memset.i32(i8 * <dest>, i8 <val>,
+ i32 <len>, i32 <align>)
+ declare void %llvm.memset.i64(i8 * <dest>, i8 <val>,
+ i64 <len>, i32 <align>)
</pre>
<h5>Overview:</h5>
<p>
-The '<tt>llvm.memset</tt>' intrinsic fills a block of memory with a particular
+The '<tt>llvm.memset.*</tt>' intrinsics fill a block of memory with a particular
byte value.
</p>
<p>
The first argument is a pointer to the destination to fill, the second is the
-byte value to fill it with, the third argument is an (arbitrarily sized) integer
+byte value to fill it with, the third argument is an integer
argument specifying the number of bytes to fill, and the fourth argument is the
known alignment of destination location.
</p>
<p>
If the call to this intrinisic has an alignment value that is not 0 or 1, then
-the caller guarantees that the size of the copy is a multiple of the alignment
-and that the destination pointer is aligned to that boundary.
+the caller guarantees that the destination pointer is aligned to that boundary.
</p>
<h5>Semantics:</h5>
<p>
-The '<tt>llvm.memset</tt>' intrinsic fills "len" bytes of memory starting at the
+The '<tt>llvm.memset.*</tt>' intrinsics fill "len" bytes of memory starting at
+the
destination location. If the argument is known to be aligned to some boundary,
this can be specified as the fourth argument, otherwise it should be set to 0 or
1.
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_isunordered">'<tt>llvm.isunordered</tt>' Intrinsic</a>
+ <a name="i_isunordered">'<tt>llvm.isunordered.*</tt>' Intrinsic</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- declare bool %llvm.isunordered(<float or double> Val1, <float or double> Val2)
+ declare bool %llvm.isunordered.f32(float Val1, float Val2)
+ declare bool %llvm.isunordered.f64(double Val1, double Val2)
</pre>
<h5>Overview:</h5>
<p>
-The '<tt>llvm.isunordered</tt>' intrinsic returns true if either or both of the
+The '<tt>llvm.isunordered</tt>' intrinsics return true if either or both of the
specified floating point values is a NAN.
</p>
</div>
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="i_sqrt">'<tt>llvm.sqrt.*</tt>' Intrinsic</a>
+</div>
+
+<div class="doc_text">
+
+<h5>Syntax:</h5>
+<pre>
+ declare float %llvm.sqrt.f32(float %Val)
+ declare double %llvm.sqrt.f64(double %Val)
+</pre>
+
+<h5>Overview:</h5>
+
+<p>
+The '<tt>llvm.sqrt</tt>' intrinsics return the sqrt of the specified operand,
+returning the same value as the libm '<tt>sqrt</tt>' function would. Unlike
+<tt>sqrt</tt> in libm, however, <tt>llvm.sqrt</tt> has undefined behavior for
+negative numbers (which allows for better optimization).
+</p>
+
+<h5>Arguments:</h5>
+
+<p>
+The argument and return value are floating point numbers of the same type.
+</p>
+
+<h5>Semantics:</h5>
+
+<p>
+This function returns the sqrt of the specified operand if it is a positive
+floating point number.
+</p>
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="i_powi">'<tt>llvm.powi.*</tt>' Intrinsic</a>
+</div>
+
+<div class="doc_text">
+
+<h5>Syntax:</h5>
+<pre>
+ declare float %llvm.powi.f32(float %Val, i32 %power)
+ declare double %llvm.powi.f64(double %Val, i32 %power)
+</pre>
+
+<h5>Overview:</h5>
+
+<p>
+The '<tt>llvm.powi.*</tt>' intrinsics return the first operand raised to the
+specified (positive or negative) power. The order of evaluation of
+multiplications is not defined.
+</p>
+
+<h5>Arguments:</h5>
+
+<p>
+The second argument is an integer power, and the first is a value to raise to
+that power.
+</p>
+
+<h5>Semantics:</h5>
+
+<p>
+This function returns the first value raised to the second power with an
+unspecified sequence of rounding operations.</p>
+</div>
+
+
<!-- ======================================================================= -->
<div class="doc_subsection">
- <a name="int_count">Bit Counting Intrinsics</a>
+ <a name="int_manip">Bit Manipulation Intrinsics</a>
</div>
<div class="doc_text">
<p>
-LLVM provides intrinsics for a few important bit counting operations.
+LLVM provides intrinsics for a few important bit manipulation operations.
These allow efficient code generation for some algorithms.
</p>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="int_ctpop">'<tt>llvm.ctpop</tt>' Intrinsic</a>
+ <a name="i_bswap">'<tt>llvm.bswap.*</tt>' Intrinsics</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- declare int %llvm.ctpop(int <src>)
+ declare i16 %llvm.bswap.i16(i16 <id>)
+ declare i32 %llvm.bswap.i32(i32 <id>)
+ declare i64 %llvm.bswap.i64(i64 <id>)
+</pre>
+
+<h5>Overview:</h5>
+
+<p>
+The '<tt>llvm.bwsap</tt>' family of intrinsics is used to byteswap a 16, 32 or
+64 bit quantity. These are useful for performing operations on data that is not
+in the target's native byte order.
+</p>
+
+<h5>Semantics:</h5>
+
+<p>
+The <tt>llvm.bswap.16</tt> intrinsic returns an i16 value that has the high
+and low byte of the input i16 swapped. Similarly, the <tt>llvm.bswap.i32</tt>
+intrinsic returns an i32 value that has the four bytes of the input i32
+swapped, so that if the input bytes are numbered 0, 1, 2, 3 then the returned
+i32 will have its bytes in 3, 2, 1, 0 order. The <tt>llvm.bswap.i64</tt>
+intrinsic extends this concept to 64 bits.
+</p>
+
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="int_ctpop">'<tt>llvm.ctpop.*</tt>' Intrinsic</a>
+</div>
+
+<div class="doc_text">
+<h5>Syntax:</h5>
+<pre>
+ declare i8 %llvm.ctpop.i8 (i8 <src>)
+ declare i16 %llvm.ctpop.i16(i16 <src>)
+ declare i32 %llvm.ctpop.i32(i32 <src>)
+ declare i64 %llvm.ctpop.i64(i64 <src>)
</pre>
<h5>Overview:</h5>
<p>
-The '<tt>llvm.ctpop</tt>' intrinsic counts the number of ones in a variable.
+The '<tt>llvm.ctpop</tt>' family of intrinsics counts the number of bits set in a
+value.
</p>
<h5>Arguments:</h5>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="int_cttz">'<tt>llvm.cttz</tt>' Intrinsic</a>
+ <a name="int_ctlz">'<tt>llvm.ctlz.*</tt>' Intrinsic</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- declare int %llvm.cttz(int <src>)
-
+ declare i8 %llvm.ctlz.i8 (i8 <src>)
+ declare i16 %llvm.ctlz.i16(i16 <src>)
+ declare i32 %llvm.ctlz.i32(i32 <src>)
+ declare i64 %llvm.ctlz.i64(i64 <src>)
</pre>
<h5>Overview:</h5>
<p>
-The '<tt>llvm.cttz</tt>' intrinsic counts the number of trailing zeros.
+The '<tt>llvm.ctlz</tt>' family of intrinsic functions counts the number of
+leading zeros in a variable.
</p>
<h5>Arguments:</h5>
<p>
The only argument is the value to be counted. The argument may be of any
-integer type. The return type must match the argument type.
+integer type. The return type must match the argument type.
</p>
<h5>Semantics:</h5>
<p>
-The '<tt>llvm.cttz</tt>' intrinsic counts the trailing zeros in a variable. If
-the src == 0 then the result is the size in bits of the type of src.
+The '<tt>llvm.ctlz</tt>' intrinsic counts the leading (most significant) zeros
+in a variable. If the src == 0 then the result is the size in bits of the type
+of src. For example, <tt>llvm.ctlz(i32 2) = 30</tt>.
</p>
</div>
+
+
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="int_ctlz">'<tt>llvm.ctlz</tt>' Intrinsic</a>
+ <a name="int_cttz">'<tt>llvm.cttz.*</tt>' Intrinsic</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- declare int %llvm.ctlz(int <src>)
-
+ declare i8 %llvm.cttz.i8 (i8 <src>)
+ declare i16 %llvm.cttz.i16(i16 <src>)
+ declare i32 %llvm.cttz.i32(i32 <src>)
+ declare i64 %llvm.cttz.i64(i64 <src>)
</pre>
<h5>Overview:</h5>
<p>
-The '<tt>llvm.ctlz</tt>' intrinsic counts the number of leading zeros in a
-variable.
+The '<tt>llvm.cttz</tt>' family of intrinsic functions counts the number of
+trailing zeros.
</p>
<h5>Arguments:</h5>
<p>
The only argument is the value to be counted. The argument may be of any
-integer type. The return type must match the argument type.
+integer type. The return type must match the argument type.
</p>
<h5>Semantics:</h5>
<p>
-The '<tt>llvm.ctlz</tt>' intrinsic counts the leading zeros in a variable. If
-the src == 0 then the result is the size in bits of the type of src.
+The '<tt>llvm.cttz</tt>' intrinsic counts the trailing (least significant) zeros
+in a variable. If the src == 0 then the result is the size in bits of the type
+of src. For example, <tt>llvm.cttz(2) = 1</tt>.
</p>
</div>
-
<!-- ======================================================================= -->
<div class="doc_subsection">
<a name="int_debugger">Debugger Intrinsics</a>
src="http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01!" /></a>
<a href="mailto:sabre@nondot.org">Chris Lattner</a><br>
- <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br>
+ <a href="http://llvm.org">The LLVM Compiler Infrastructure</a><br>
Last modified: $Date$
</address>
</body>
projects / oota-llvm.git / blobdiff