<li><a href="#callingconv">Calling Conventions</a></li>
<li><a href="#globalvars">Global Variables</a></li>
<li><a href="#functionstructure">Functions</a></li>
+ <li><a href="#aliasstructure">Aliases</a>
<li><a href="#paramattrs">Parameter Attributes</a></li>
<li><a href="#moduleasm">Module-Level Inline Assembly</a></li>
+ <li><a href="#datalayout">Data Layout</a></li>
</ol>
</li>
<li><a href="#typesystem">Type System</a>
<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_vector">Vector Type</a></li>
<li><a href="#t_opaque">Opaque Type</a></li>
</ol>
</li>
<ol>
<li><a href="#int_varargs">Variable Argument Handling Intrinsics</a>
<ol>
- <li><a href="#i_va_start">'<tt>llvm.va_start</tt>' Intrinsic</a></li>
- <li><a href="#i_va_end">'<tt>llvm.va_end</tt>' Intrinsic</a></li>
- <li><a href="#i_va_copy">'<tt>llvm.va_copy</tt>' Intrinsic</a></li>
+ <li><a href="#int_va_start">'<tt>llvm.va_start</tt>' Intrinsic</a></li>
+ <li><a href="#int_va_end">'<tt>llvm.va_end</tt>' Intrinsic</a></li>
+ <li><a href="#int_va_copy">'<tt>llvm.va_copy</tt>' Intrinsic</a></li>
</ol>
</li>
<li><a href="#int_gc">Accurate Garbage Collection Intrinsics</a>
<ol>
- <li><a href="#i_gcroot">'<tt>llvm.gcroot</tt>' Intrinsic</a></li>
- <li><a href="#i_gcread">'<tt>llvm.gcread</tt>' Intrinsic</a></li>
- <li><a href="#i_gcwrite">'<tt>llvm.gcwrite</tt>' Intrinsic</a></li>
+ <li><a href="#int_gcroot">'<tt>llvm.gcroot</tt>' Intrinsic</a></li>
+ <li><a href="#int_gcread">'<tt>llvm.gcread</tt>' Intrinsic</a></li>
+ <li><a href="#int_gcwrite">'<tt>llvm.gcwrite</tt>' Intrinsic</a></li>
</ol>
</li>
<li><a href="#int_codegen">Code Generator Intrinsics</a>
<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>
+ <li><a href="#int_returnaddress">'<tt>llvm.returnaddress</tt>' Intrinsic</a></li>
+ <li><a href="#int_frameaddress">'<tt>llvm.frameaddress</tt>' Intrinsic</a></li>
+ <li><a href="#int_stacksave">'<tt>llvm.stacksave</tt>' Intrinsic</a></li>
+ <li><a href="#int_stackrestore">'<tt>llvm.stackrestore</tt>' Intrinsic</a></li>
+ <li><a href="#int_prefetch">'<tt>llvm.prefetch</tt>' Intrinsic</a></li>
+ <li><a href="#int_pcmarker">'<tt>llvm.pcmarker</tt>' Intrinsic</a></li>
+ <li><a href="#int_readcyclecounter"><tt>llvm.readcyclecounter</tt>' Intrinsic</a></li>
</ol>
</li>
<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_sqrt">'<tt>llvm.sqrt.*</tt>' Intrinsic</a></li>
- <li><a href="#i_powi">'<tt>llvm.powi.*</tt>' Intrinsic</a></li>
+ <li><a href="#int_memcpy">'<tt>llvm.memcpy.*</tt>' Intrinsic</a></li>
+ <li><a href="#int_memmove">'<tt>llvm.memmove.*</tt>' Intrinsic</a></li>
+ <li><a href="#int_memset">'<tt>llvm.memset.*</tt>' Intrinsic</a></li>
+ <li><a href="#int_sqrt">'<tt>llvm.sqrt.*</tt>' Intrinsic</a></li>
+ <li><a href="#int_powi">'<tt>llvm.powi.*</tt>' Intrinsic</a></li>
</ol>
</li>
<li><a href="#int_manip">Bit Manipulation Intrinsics</a>
<ol>
- <li><a href="#i_bswap">'<tt>llvm.bswap.*</tt>' Intrinsics</a></li>
+ <li><a href="#int_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>
+ <li><a href="#int_part_select">'<tt>llvm.part.select.*</tt>' Intrinsic </a></li>
+ <li><a href="#int_part_set">'<tt>llvm.part.set.*</tt>' Intrinsic </a></li>
</ol>
</li>
<li><a href="#int_debugger">Debugger intrinsics</a></li>
+ <li><a href="#int_eh">Exception Handling intrinsics</a></li>
+ <li><a href="#int_trampoline">Trampoline Intrinsic</a>
+ <ol>
+ <li><a href="#int_it">'<tt>llvm.init.trampoline</tt>' Intrinsic</a></li>
+ </ol>
+ </li>
+ <li><a href="#int_general">General intrinsics</a>
+ <ol>
+ <li><a href="#int_var_annotation">
+ <tt>llvm.var.annotation</tt>' Intrinsic</a></li>
+ </ol>
+ <ol>
+ <li><a href="#int_annotation">
+ <tt>llvm.annotation.*</tt>' Intrinsic</a></li>
+ </ol>
+ </li>
</ol>
</li>
</ol>
<div class="doc_text">
<p>The LLVM code representation is designed to be used in three
-different forms: as an in-memory compiler IR, as an on-disk bytecode
+different forms: as an in-memory compiler IR, as an on-disk bitcode
representation (suitable for fast loading by a Just-In-Time compiler),
and as a human readable assembly language representation. This allows
LLVM to provide a powerful intermediate representation for efficient
accepts and what is considered 'well formed'. For example, the
following instruction is syntactically okay, but not well formed:</p>
+<div class="doc_code">
<pre>
-
%x = <a href="#i_add">add</a> i32 1, %x
+%x = <a href="#i_add">add</a> i32 1, %x
</pre>
+</div>
<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
-the optimizer before it outputs bytecode. The violations pointed out
+the optimizer before it outputs bitcode. The violations pointed out
by the verifier pass indicate bugs in transformation passes or input to
the parser.</p>
+</div>
-<!-- Describe the typesetting conventions here. --> </div>
+<!-- Describe the typesetting conventions here. -->
<!-- *********************************************************************** -->
<div class="doc_section"> <a name="identifiers">Identifiers</a> </div>
<div class="doc_text">
-<p>LLVM uses three different forms of identifiers, for different
-purposes:</p>
+ <p>LLVM identifiers come in two basic types: global and local. Global
+ identifiers (functions, global variables) begin with the @ character. Local
+ identifiers (register names, types) begin with the % character. Additionally,
+ there are three different formats for identifiers, for different purposes:
<ol>
- <li>Named values are represented as a string of characters with a '%' prefix.
- For example, %foo, %DivisionByZero, %a.really.long.identifier. The actual
- regular expression used is '<tt>%[a-zA-Z$._][a-zA-Z$._0-9]*</tt>'.
+ <li>Named values are represented as a string of characters with their prefix.
+ For example, %foo, @DivisionByZero, %a.really.long.identifier. The actual
+ regular expression used is '<tt>[%@][a-zA-Z$._][a-zA-Z$._0-9]*</tt>'.
Identifiers which require other characters in their names can be surrounded
- with quotes. In this way, anything except a <tt>"</tt> character can be used
- in a name.</li>
+ with quotes. In this way, anything except a <tt>"</tt> character can
+ be used in a named value.</li>
- <li>Unnamed values are represented as an unsigned numeric value with a '%'
- prefix. For example, %12, %2, %44.</li>
+ <li>Unnamed values are represented as an unsigned numeric value with their
+ prefix. For example, %12, @2, %44.</li>
<li>Constants, which are described in a <a href="#constants">section about
constants</a>, below.</li>
</ol>
-<p>LLVM requires that values start with a '%' sign for two reasons: Compilers
+<p>LLVM requires that values start with a prefix for two reasons: Compilers
don't need to worry about name clashes with reserved words, and the set of
reserved words may be expanded in the future without penalty. Additionally,
unnamed identifiers allow a compiler to quickly come up with a temporary
'<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>
+none of them start with a prefix character ('%' or '@').</p>
<p>Here is an example of LLVM code to multiply the integer variable
'<tt>%X</tt>' by 8:</p>
<p>The easy way:</p>
+<div class="doc_code">
<pre>
-
%result = <a href="#i_mul">mul</a> i32 %X, 8
+%result = <a href="#i_mul">mul</a> i32 %X, 8
</pre>
+</div>
<p>After strength reduction:</p>
+<div class="doc_code">
<pre>
-
%result = <a href="#i_shl">shl</a> i32 %X, i8 3
+%result = <a href="#i_shl">shl</a> i32 %X, i8 3
</pre>
+</div>
<p>And the hard way:</p>
+<div class="doc_code">
<pre>
-
<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
+<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>
+</div>
<p>This last way of multiplying <tt>%X</tt> by 8 illustrates several
important lexical features of LLVM:</p>
global variable) definitions, resolves forward declarations, and merges
symbol table entries. Here is an example of the "hello world" module:</p>
+<div class="doc_code">
<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 i8 ]</a> c"hello world\0A\00" <i>; [13 x i8 ]*</i>
+<a href="#identifiers">
@.LC0</a> = <a href="#linkage_internal">internal</a> <a
+ 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> i32 %puts(i8 *) <i>; i32(i8 *)* </i>
-
-<i>; Global variable / Function body section separator</i>
-implementation
+<a href="#functionstructure">declare</a> i32 @puts(i8 *) <i>; i32(i8 *)* </i>
<i>; Definition of main function</i>
-define i32 %main() { <i>; i32()* </i>
+define i32 @main() { <i>; i32()* </i>
<i>; Convert [13x i8 ]* to i8 *...</i>
%cast210 = <a
- href="#i_getelementptr">getelementptr</a> [13 x i8 ]* %.LC0, i64 0, i64 0 <i>; i8 *</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> i32 %puts(i8 * %cast210) <i>; i32</i>
+ href="#i_call">call</a> i32 @puts(i8 * %cast210) <i>; i32</i>
<a
- href="#i_ret">ret</a> i32 0<br>}<br></pre>
+ href="#i_ret">ret</a> i32 0<br>}<br>
+</pre>
+</div>
<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>
<!-- ======================================================================= -->
until linked, if not linked, the symbol becomes null instead of being an
undefined reference.
</dd>
-</dl>
<dt><tt><b><a name="linkage_external">externally visible</a></b></tt>:</dt>
visible, meaning that it participates in linkage and can be used to resolve
external symbol references.
</dd>
+</dl>
<p>
The next two types of linkage are targeted for Microsoft Windows platform
<p>It is illegal for a function <i>declaration</i>
to have any linkage type other than "externally visible", <tt>dllimport</tt>,
or <tt>extern_weak</tt>.</p>
-
+<p>Aliases can have only <tt>external</tt>, <tt>internal</tt> and <tt>weak</tt>
+linkages.
</div>
<!-- ======================================================================= -->
directly.
</dd>
+ <dt><b>"<tt>protected</tt>" - Protected style</b>:</dt>
+
+ <dd>On ELF, protected visibility indicates that the symbol will be placed in
+ the dynamic symbol table, but that references within the defining module will
+ bind to the local symbol. That is, the symbol cannot be overridden by another
+ module.
+ </dd>
</dl>
</div>
<p>Global variables define regions of memory allocated at compilation time
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
+an explicit section to be placed in, and may have an optional explicit alignment
+specified. A variable may be defined as "thread_local", which means that it
+will not be shared by threads (each thread will have a separated copy of the
+variable). 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>
<p>For example, the following defines a global with an initializer, section,
and alignment:</p>
+<div class="doc_code">
<pre>
- %G = constant float 1.0, section "foo", align 4
+@G = constant float 1.0, section "foo", align 4
</pre>
+</div>
</div>
with a <a href="#terminators">terminator</a> instruction (such as a branch or
function return).</p>
-<p>The first basic block in a program is special in two ways: it is immediately
+<p>The first basic block in a function 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
<a href="#i_phi">PHI nodes</a>.</p>
-<p>LLVM functions are identified by their name and type signature. Hence, two
-functions with the same name but different parameter lists or return values are
-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>
</div>
+
+<!-- ======================================================================= -->
+<div class="doc_subsection">
+ <a name="aliasstructure">Aliases</a>
+</div>
+<div class="doc_text">
+ <p>Aliases act as "second name" for the aliasee value (which can be either
+ function or global variable or bitcast of global value). Aliases may have an
+ optional <a href="#linkage">linkage type</a>, and an
+ optional <a href="#visibility">visibility style</a>.</p>
+
+ <h5>Syntax:</h5>
+
+<div class="doc_code">
+<pre>
+@<Name> = [Linkage] [Visibility] alias <AliaseeTy> @<Aliasee>
+</pre>
+</div>
+
+</div>
+
+
+
<!-- ======================================================================= -->
<div class="doc_subsection"><a name="paramattrs">Parameter Attributes</a></div>
<div class="doc_text">
<p>Parameter attributes are simple keywords that follow the type specified. If
multiple parameter attributes are needed, they are space separated. For
- example:</p><pre>
- %someFunc = i16 (i8 sext %someParam) zext
- %someFunc = i16 (i8 zext %someParam) zext</pre>
+ example:</p>
+
+<div class="doc_code">
+<pre>
+%someFunc = i16 (i8 signext %someParam) zeroext
+%someFunc = i16 (i8 zeroext %someParam) zeroext
+</pre>
+</div>
+
<p>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). Also note
- that the attribute for the function result (zext) comes immediately after the
- argument list.</p>
+ a different attribute (<tt>signext</tt> in the first one, <tt>zeroext</tt> in
+ the second). Also note that the attribute for the function result
+ (<tt>zeroext</tt>) comes immediately after the argument list.</p>
<p>Currently, only the following parameter attributes are defined:</p>
<dl>
- <dt><tt>zext</tt></dt>
+ <dt><tt>zeroext</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>
+ <dt><tt>signext</tt></dt>
<dd>This indicates that the parameter should be sign extended just before
a call to this function.</dd>
<dt><tt>inreg</tt></dt>
target-specific</dd>
<dt><tt>sret</tt></dt>
<dd>This indicates that the parameter specifies the address of a structure
- that is the return value of the function in the source program.
- </dd>
+ that is the return value of the function in the source program.</dd>
+ <dt><tt>noalias</tt></dt>
+ <dd>This indicates that the parameter not alias any other object or any
+ other "noalias" objects during the function call.
+ <dt><tt>noreturn</tt></dt>
+ <dd>This function attribute indicates that the function never returns. This
+ indicates to LLVM that every call to this function should be treated as if
+ an <tt>unreachable</tt> instruction immediately followed the call.</dd>
+ <dt><tt>nounwind</tt></dt>
+ <dd>This function attribute indicates that the function type does not use
+ the unwind instruction and does not allow stack unwinding to propagate
+ through it.</dd>
+ <dt><tt>nest</tt></dt>
+ <dd>This indicates that the parameter can be excised using the
+ <a href="#int_trampoline">trampoline intrinsics</a>.</dd>
</dl>
</div>
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>
+<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
</p>
</div>
+<!-- ======================================================================= -->
+<div class="doc_subsection">
+ <a name="datalayout">Data Layout</a>
+</div>
+
+<div class="doc_text">
+<p>A module may specify a target specific data layout string that specifies how
+data is to be laid out in memory. The syntax for the data layout is simply:</p>
+<pre> target datalayout = "<i>layout specification</i>"</pre>
+<p>The <i>layout specification</i> consists of a list of specifications
+separated by the minus sign character ('-'). Each specification starts with a
+letter and may include other information after the letter to define some
+aspect of the data layout. The specifications accepted are as follows: </p>
+<dl>
+ <dt><tt>E</tt></dt>
+ <dd>Specifies that the target lays out data in big-endian form. That is, the
+ bits with the most significance have the lowest address location.</dd>
+ <dt><tt>e</tt></dt>
+ <dd>Specifies that hte target lays out data in little-endian form. That is,
+ the bits with the least significance have the lowest address location.</dd>
+ <dt><tt>p:<i>size</i>:<i>abi</i>:<i>pref</i></tt></dt>
+ <dd>This specifies the <i>size</i> of a pointer and its <i>abi</i> and
+ <i>preferred</i> alignments. All sizes are in bits. Specifying the <i>pref</i>
+ alignment is optional. If omitted, the preceding <tt>:</tt> should be omitted
+ too.</dd>
+ <dt><tt>i<i>size</i>:<i>abi</i>:<i>pref</i></tt></dt>
+ <dd>This specifies the alignment for an integer type of a given bit
+ <i>size</i>. The value of <i>size</i> must be in the range [1,2^23).</dd>
+ <dt><tt>v<i>size</i>:<i>abi</i>:<i>pref</i></tt></dt>
+ <dd>This specifies the alignment for a vector type of a given bit
+ <i>size</i>.</dd>
+ <dt><tt>f<i>size</i>:<i>abi</i>:<i>pref</i></tt></dt>
+ <dd>This specifies the alignment for a floating point type of a given bit
+ <i>size</i>. The value of <i>size</i> must be either 32 (float) or 64
+ (double).</dd>
+ <dt><tt>a<i>size</i>:<i>abi</i>:<i>pref</i></tt></dt>
+ <dd>This specifies the alignment for an aggregate type of a given bit
+ <i>size</i>.</dd>
+</dl>
+<p>When constructing the data layout for a given target, LLVM starts with a
+default set of specifications which are then (possibly) overriden by the
+specifications in the <tt>datalayout</tt> keyword. The default specifications
+are given in this list:</p>
+<ul>
+ <li><tt>E</tt> - big endian</li>
+ <li><tt>p:32:64:64</tt> - 32-bit pointers with 64-bit alignment</li>
+ <li><tt>i1:8:8</tt> - i1 is 8-bit (byte) aligned</li>
+ <li><tt>i8:8:8</tt> - i8 is 8-bit (byte) aligned</li>
+ <li><tt>i16:16:16</tt> - i16 is 16-bit aligned</li>
+ <li><tt>i32:32:32</tt> - i32 is 32-bit aligned</li>
+ <li><tt>i64:32:64</tt> - i64 has abi alignment of 32-bits but preferred
+ alignment of 64-bits</li>
+ <li><tt>f32:32:32</tt> - float is 32-bit aligned</li>
+ <li><tt>f64:64:64</tt> - double is 64-bit aligned</li>
+ <li><tt>v64:64:64</tt> - 64-bit vector is 64-bit aligned</li>
+ <li><tt>v128:128:128</tt> - 128-bit vector is 128-bit aligned</li>
+ <li><tt>a0:0:1</tt> - aggregates are 8-bit aligned</li>
+</ul>
+<p>When llvm is determining the alignment for a given type, it uses the
+following rules:
+<ol>
+ <li>If the type sought is an exact match for one of the specifications, that
+ specification is used.</li>
+ <li>If no match is found, and the type sought is an integer type, then the
+ smallest integer type that is larger than the bitwidth of the sought type is
+ used. If none of the specifications are larger than the bitwidth then the the
+ largest integer type is used. For example, given the default specifications
+ above, the i7 type will use the alignment of i8 (next largest) while both
+ i65 and i256 will use the alignment of i64 (largest specified).</li>
+ <li>If no match is found, and the type sought is a vector type, then the
+ largest vector type that is smaller than the sought vector type will be used
+ as a fall back. This happens because <128 x double> can be implemented in
+ terms of 64 <2 x double>, for example.</li>
+</ol>
+</div>
<!-- *********************************************************************** -->
<div class="doc_section"> <a name="typesystem">Type System</a> </div>
<table>
<tbody>
<tr><th>Type</th><th>Description</th></tr>
- <tr><td><tt>void</tt></td><td>No value</td></tr>
- <tr><td><tt>i8</tt></td><td>8-bit value</td></tr>
- <tr><td><tt>i32</tt></td><td>32-bit value</td></tr>
- <tr><td><tt>float</tt></td><td>32-bit floating point value</td></tr>
+ <tr><td><tt><a name="t_void">void</a></tt></td><td>No value</td></tr>
<tr><td><tt>label</tt></td><td>Branch destination</td></tr>
</tbody>
</table>
<table>
<tbody>
<tr><th>Type</th><th>Description</th></tr>
- <tr><td><tt>i1</tt></td><td>True or False value</td></tr>
- <tr><td><tt>i16</tt></td><td>16-bit value</td></tr>
- <tr><td><tt>i64</tt></td><td>64-bit value</td></tr>
+ <tr><td><tt>float</tt></td><td>32-bit floating point value</td></tr>
<tr><td><tt>double</tt></td><td>64-bit floating point value</td></tr>
</tbody>
</table>
<tr><th>Classification</th><th>Types</th></tr>
<tr>
<td><a name="t_integer">integer</a></td>
- <td><tt>i1, i8, i16, i32, i64</tt></td>
+ <td><tt>i1, i2, i3, ... i8, ... i16, ... i32, ... i64, ... </tt></td>
</tr>
<tr>
<td><a name="t_floating">floating point</a></td>
</tr>
<tr>
<td><a name="t_firstclass">first class</a></td>
- <td><tt>i1, i8, i16, i32, i64, float, double, <br/>
- <a href="#t_pointer">pointer</a>,<a href="#t_packed">packed</a></tt>
+ <td><tt>i1, ..., float, double, <br/>
+ <a href="#t_pointer">pointer</a>,<a href="#t_vector">vector</a></tt>
</td>
</tr>
</tbody>
</div>
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection"> <a name="t_integer">Integer Type</a> </div>
+
+<div class="doc_text">
+
+<h5>Overview:</h5>
+<p>The integer type is a very simple derived type that simply specifies an
+arbitrary bit width for the integer type desired. Any bit width from 1 bit to
+2^23-1 (about 8 million) can be specified.</p>
+
+<h5>Syntax:</h5>
+
+<pre>
+ iN
+</pre>
+
+<p>The number of bits the integer will occupy is specified by the <tt>N</tt>
+value.</p>
+
+<h5>Examples:</h5>
+<table class="layout">
+ <tr class="layout">
+ <td class="left">
+ <tt>i1</tt><br/>
+ <tt>i4</tt><br/>
+ <tt>i8</tt><br/>
+ <tt>i16</tt><br/>
+ <tt>i32</tt><br/>
+ <tt>i42</tt><br/>
+ <tt>i64</tt><br/>
+ <tt>i1942652</tt><br/>
+ </td>
+ <td class="left">
+ A boolean integer of 1 bit<br/>
+ A nibble sized integer of 4 bits.<br/>
+ A byte sized integer of 8 bits.<br/>
+ A half word sized integer of 16 bits.<br/>
+ A word sized integer of 32 bits.<br/>
+ An integer whose bit width is the answer. <br/>
+ A double word sized integer of 64 bits.<br/>
+ A really big integer of over 1 million bits.<br/>
+ </td>
+ </tr>
+</table>
+</div>
+
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection"> <a name="t_array">Array Type</a> </div>
<td class="left">function taking an <tt>i32</tt>, returning an <tt>i32</tt>
</td>
</tr><tr class="layout">
- <td class="left"><tt>float (i16 sext, i32 *) *
+ <td class="left"><tt>float (i16 signext, 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
<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>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>
+ <td class="left"><tt>{ i32, i32, i32 }</tt></td>
+ <td class="left">A triple of three <tt>i32</tt> values</td>
+ </tr><tr class="layout">
+ <td class="left"><tt>{ float, i32 (i32) * }</tt></td>
+ <td class="left">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>.</td>
</tr>
</table>
</div>
<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>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>
+ <td class="left"><tt>< { i32, i32, i32 } ></tt></td>
+ <td class="left">A triple of three <tt>i32</tt> values</td>
+ </tr><tr class="layout">
+ <td class="left"><tt>< { float, i32 (i32) * } ></tt></td>
+ <td class="left">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>.</td>
</tr>
</table>
</div>
</div>
<!-- _______________________________________________________________________ -->
-<div class="doc_subsubsection"> <a name="t_packed">Packed Type</a> </div>
+<div class="doc_subsubsection"> <a name="t_vector">Vector Type</a> </div>
<div class="doc_text">
<h5>Overview:</h5>
-<p>A packed type is a simple derived type that represents a vector
-of elements. Packed types are used when multiple primitive data
+<p>A vector type is a simple derived type that represents a vector
+of elements. Vector types are used when multiple primitive data
are operated in parallel using a single instruction (SIMD).
-A packed type requires a size (number of
+A vector type requires a size (number of
elements) and an underlying primitive data type. Vectors must have a power
-of two length (1, 2, 4, 8, 16 ...). Packed types are
+of two length (1, 2, 4, 8, 16 ...). Vector types are
considered <a href="#t_firstclass">first class</a>.</p>
<h5>Syntax:</h5>
<tt><2 x i64></tt><br/>
</td>
<td class="left">
- Packed vector of 4 32-bit integer values.<br/>
- Packed vector of 8 floating-point values.<br/>
- Packed vector of 2 64-bit integer values.<br/>
+ Vector of 4 32-bit integer values.<br/>
+ Vector of 8 floating-point values.<br/>
+ Vector of 2 64-bit integer values.<br/>
</td>
</tr>
</table>
<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>{ i32 4, float 17.0, i32* %G }</tt>",
- where "<tt>%G</tt>" is declared as "<tt>%G = external global i32</tt>". Structure constants
+ 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>
types of elements must match those specified by the type.
</dd>
- <dt><b>Packed constants</b></dt>
+ <dt><b>Vector constants</b></dt>
- <dd>Packed constants are represented with notation similar to packed type
+ <dd>Vector constants are represented with notation similar to vector type
definitions (a comma separated list of elements, surrounded by
less-than/greater-than's (<tt><></tt>)). For example: "<tt>< i32 42,
- i32 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
+ i32 11, i32 74, i32 100 ></tt>".
Vector constants must have <a
+ href="#t_vector">vector type</a>, and the number and types of elements must
match those specified by the type.
</dd>
href="#t_pointer">pointer</a> type. For example, the following is a legal LLVM
file:</p>
+<div class="doc_code">
<pre>
- %X = global i32 17
- %Y = global i32 42
- %Z = global [2 x i32*] [ i32* %X, i32* %Y ]
+@X = global i32 17
+@Y = global i32 42
+@Z = global [2 x i32*] [ i32* @X, i32* @Y ]
</pre>
+</div>
</div>
<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>
+ <dt><b><tt>fptoui ( 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>
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
+ vector 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>
inline assembler expression is:
</p>
+<div class="doc_code">
<pre>
- i32 (i32) asm "bswap $0", "=r,r"
+i32 (i32) asm "bswap $0", "=r,r"
</pre>
+</div>
<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>
+<div class="doc_code">
<pre>
- %X = call i32 asm "<a href="#i_bswap">bswap</a> $0", "=r,r"(i32 %Y)
+%X = call i32 asm "<a href="#int_bswap">bswap</a> $0", "=r,r"(i32 %Y)
</pre>
+</div>
<p>
Inline asms with side effects not visible in the constraint list must be marked
'<tt>sideeffect</tt>' keyword, like so:
</p>
+<div class="doc_code">
<pre>
- call void asm sideeffect "eieio", ""()
+call void asm sideeffect "eieio", ""()
</pre>
+</div>
<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
<h5>Arguments:</h5>
<p>The conditional branch form of the '<tt>br</tt>' instruction takes a
single '<tt>i1</tt>' value and two '<tt>label</tt>' values. The
-unconditional form of the '<tt>br</tt>' instruction takes a single '<tt>label</tt>'
-value as a target.</p>
+unconditional form of the '<tt>br</tt>' instruction takes a single
+'<tt>label</tt>' value as a target.</p>
<h5>Semantics:</h5>
<p>Upon execution of a conditional '<tt>br</tt>' instruction, the '<tt>i1</tt>'
argument is evaluated. If the value is <tt>true</tt>, control flows
<ol>
<li>
- 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 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>
+ %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>Binary operators are used to do most of the computation in a
program. They require two operands, execute an operation on them, and
produce a single value. The operands might represent
-multiple data, as is the case with the <a href="#t_packed">packed</a> data type.
+multiple data, as is the case with the <a href="#t_vector">vector</a> data type.
The result value of a binary operator is not
necessarily the same type as its operands.</p>
<p>There are several different binary operators:</p>
<h5>Arguments:</h5>
<p>The two arguments to the '<tt>add</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.
+ This instruction can also take <a href="#t_vector">vector</a> versions of the values.
Both arguments must have identical types.</p>
<h5>Semantics:</h5>
<p>The value produced is the integer or floating point sum of the two
<p>The two arguments to the '<tt>sub</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.
+This instruction can also take <a href="#t_vector">vector</a> versions of the values.
Both arguments must have identical types.</p>
<h5>Semantics:</h5>
<p>The value produced is the integer or floating point difference of
the two operands.</p>
<h5>Example:</h5>
-<pre> <result> = sub i32 4, %var <i>; yields {i32}:result = 4 - %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>
<p>The two arguments to the '<tt>mul</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.
+This instruction can also take <a href="#t_vector">vector</a> versions of the values.
Both arguments must have identical types.</p>
<h5>Semantics:</h5>
<p>The value produced is the integer or floating point product of the
<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
+types. This instruction can also take <a href="#t_vector">vector</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
<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
+types. This instruction can also take <a href="#t_vector">vector</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
<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
+<p>The two arguments to the '<tt>fdiv</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>
+identical types. This instruction can also take <a href="#t_vector">vector</a>
+versions of floating point values.</p>
<h5>Semantics:</h5>
<p>The value produced is the floating point quotient of the two operands.</p>
<h5>Example:</h5>
types.</p>
<h5>Semantics:</h5>
<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
+has the same sign as the dividend, <tt>var1</tt>), not the <i>modulo</i>
+operator (where the result has the same sign as the divisor, <tt>var2</tt>) of
+
a value. For more information about the difference, see <a
href="http://mathforum.org/dr.math/problems/anne.4.28.99.html">The
-Math Forum</a>.</p>
+Math Forum</a>. For a table of how this is implemented in various languages,
+please see <a href="http://en.wikipedia.org/wiki/Modulo_operation">
+Wikipedia: modulo operation</a>.</p>
<h5>Example:</h5>
<pre> <result> = srem i32 4, %var <i>; yields {i32}:result = 4 % %var</i>
</pre>
<h5>Syntax:</h5>
<pre> <result> = shl <ty> <var1>, <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>Both arguments to the '<tt>shl</tt>' instruction must be the same <a
href="#t_integer">integer</a> type.</p>
+
<h5>Semantics:</h5>
-<p>The value produced is <tt>var1</tt> * 2<sup><tt>var2</tt></sup>.</p>
+
+<p>The value produced is <tt>var1</tt> * 2<sup><tt>var2</tt></sup>. If
+<tt>var2</tt> is (statically or dynamically) equal to or larger than the number
+of bits in <tt>var1</tt>, the result is undefined.</p>
+
<h5>Example:</h5><pre>
<result> = shl i32 4, %var <i>; yields {i32}: 4 << %var</i>
<result> = shl i32 4, 2 <i>; yields {i32}: 16</i>
<result> = shl i32 1, 10 <i>; yields {i32}: 1024</i>
+ <result> = shl i32 1, 32 <i>; undefined</i>
</pre>
</div>
<!-- _______________________________________________________________________ -->
<h5>Overview:</h5>
<p>The '<tt>lshr</tt>' instruction (logical shift right) returns the first
-operand shifted to the right a specified number of bits.</p>
+operand shifted to the right a specified number of bits with zero fill.</p>
<h5>Arguments:</h5>
<p>Both arguments to the '<tt>lshr</tt>' instruction must be the same
<a href="#t_integer">integer</a> type.</p>
<h5>Semantics:</h5>
+
<p>This instruction always performs a logical shift right operation. The most
significant bits of the result will be filled with zero bits after the
-shift.</p>
+shift. If <tt>var2</tt> is (statically or dynamically) equal to or larger than
+the number of bits in <tt>var1</tt>, the result is undefined.</p>
<h5>Example:</h5>
<pre>
<result> = lshr i32 4, 2 <i>; yields {i32}:result = 1</i>
<result> = lshr i8 4, 3 <i>; yields {i8}:result = 0</i>
<result> = lshr i8 -2, 1 <i>; yields {i8}:result = 0x7FFFFFFF </i>
+ <result> = lshr i32 1, 32 <i>; undefined</i>
</pre>
</div>
<h5>Overview:</h5>
<p>The '<tt>ashr</tt>' instruction (arithmetic shift right) returns the first
-operand shifted to the right a specified number of bits.</p>
+operand shifted to the right a specified number of bits with sign extension.</p>
<h5>Arguments:</h5>
<p>Both arguments to the '<tt>ashr</tt>' instruction must be the same
<h5>Semantics:</h5>
<p>This instruction always performs an arithmetic shift right operation,
The most significant bits of the result will be filled with the sign bit
-of <tt>var1</tt>.</p>
+of <tt>var1</tt>. If <tt>var2</tt> is (statically or dynamically) equal to or
+larger than the number of bits in <tt>var1</tt>, the result is undefined.
+</p>
<h5>Example:</h5>
<pre>
<result> = ashr i32 4, 2 <i>; yields {i32}:result = 1</i>
<result> = ashr i8 4, 3 <i>; yields {i8}:result = 0</i>
<result> = ashr i8 -2, 1 <i>; yields {i8}:result = -1</i>
+ <result> = ashr i32 1, 32 <i>; undefined</i>
</pre>
</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
+target-independent manner. These 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
<p>
The '<tt>extractelement</tt>' instruction extracts a single scalar
-element from a packed vector at a specified index.
+element from a vector at a specified index.
</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
+value of <a href="#t_vector">vector</a> type. The second operand is
an index indicating the position from which to extract the element.
The index may be a variable.</p>
<p>
The '<tt>insertelement</tt>' instruction inserts a scalar
-element into a packed vector at a specified index.
+element into a vector at a specified index.
</p>
<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
+value of <a href="#t_vector">vector</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
+The result is a 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.
<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>
+ <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>
<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>
+ %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>
<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>alloca</tt>' instruction allocates memory on the stack frame of the
+currently executing function, to be automatically released when this function
returns to its caller.</p>
<h5>Arguments:</h5>
<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, 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>
Instruction</a> </div>
<div class="doc_text">
<h5>Syntax:</h5>
-<pre> <result> = load <ty>* <pointer><br> <result> = volatile load <ty>* <pointer><br></pre>
+<pre> <result> = load <ty>* <pointer>[, align <alignment>]<br> <result> = volatile load <ty>* <pointer>[, align <alignment>]<br></pre>
<h5>Overview:</h5>
<p>The '<tt>load</tt>' instruction is used to read from memory.</p>
<h5>Arguments:</h5>
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>
+<pre> store <ty> <value>, <ty>* <pointer>[, align <alignment>] <i>; yields {void}</i>
+ volatile store <ty> <value>, <ty>* <pointer>[, align <alignment>] <i>; yields {void}</i>
</pre>
<h5>Overview:</h5>
<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 in which to store it. The type of the '<tt><pointer></tt>'
+to store and an address at 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
optimizer is not allowed to modify the number or order of execution of
<p>For example, let's consider a C code fragment and how it gets
compiled to LLVM:</p>
+<div class="doc_code">
<pre>
- struct RT {
- char A;
- i32 B[10][20];
- char C;
- };
- struct ST {
- i32 X;
- double Y;
- struct RT Z;
- };
-
- define i32 *foo(struct ST *s) {
- return &s[1].Z.B[5][13];
- }
+struct RT {
+ char A;
+ int B[10][20];
+ char C;
+};
+struct ST {
+ int X;
+ double Y;
+ struct RT Z;
+};
+
+int *foo(struct ST *s) {
+ return &s[1].Z.B[5][13];
+}
</pre>
+</div>
<p>The LLVM code generated by the GCC frontend is:</p>
+<div class="doc_code">
<pre>
- %RT = type { i8 , [10 x [20 x i32]], i8 }
- %ST = type { i32, double, %RT }
+%RT = type { i8 , [10 x [20 x i32]], i8 }
+%ST = type { i32, double, %RT }
- implementation
-
- define i32* %foo(%ST* %s) {
- entry:
- %reg = getelementptr %ST* %s, i32 1, i32 2, i32 1, i32 5, i32 13
- ret i32* %reg
- }
+define i32* %foo(%ST* %s) {
+entry:
+ %reg = getelementptr %ST* %s, i32 1, i32 2, i32 1, i32 5, i32 13
+ ret i32* %reg
+}
</pre>
+</div>
<h5>Semantics:</h5>
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>
+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>'
<pre>
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>
+ %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
<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>
+bits until it reaches the size of the destination type, <tt>ty2</tt>.</p>
<p>When zero extending from i1, the result will always be either 0 or 1.</p>
<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>
+the type <tt>ty2</tt>.</p>
<p>When sign extending from i1, the extension always results in -1 or 0.</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
+<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>
<h5>Syntax:</h5>
<pre>
- <result> = fp2uint <ty> <value> to <ty2> <i>; yields ty2</i>
+ <result> = fptoui <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
+<p>The '<tt>fptoui</tt>' converts a floating point <tt>value</tt> to its
unsigned integer equivalent of type <tt>ty2</tt>.
</p>
<h5>Arguments:</h5>
-<p>The '<tt>fp2uint</tt>' instruction takes a value to cast, which must be a
+<p>The '<tt>fptoui</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_integer">integer</a> type.</p>
<h5>Semantics:</h5>
-<p> The '<tt>fp2uint</tt>' instruction converts its
+<p> The '<tt>fptoui</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 i1, the conversion is done as a comparison against
-zero. If the <tt>value</tt> was zero, the i1 result will be <tt>false</tt>.
-If the <tt>value</tt> was non-zero, the i1 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 i1 <i>; yields i1:true</i>
- %X = fp2uint float 1.04E+17 to i8 <i>; yields undefined:1</i>
+ %X = fptoui double 123.0 to i32 <i>; yields i32:123</i>
+ %Y = fptoui float 1.0E+300 to i1 <i>; yields undefined:1</i>
+ %X = fptoui float 1.04E+17 to i8 <i>; yields undefined:1</i>
</pre>
</div>
towards zero) signed integer value. If the value cannot fit in <tt>ty2</tt>,
the results are undefined.</p>
-<p>When converting to i1, the conversion is done as a comparison against
-zero. If the <tt>value</tt> was zero, the i1 result will be <tt>false</tt>.
-If the <tt>value</tt> was non-zero, the i1 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 i1 <i>; yields i1:true</i>
+ %Y = fptosi float 1.0E-247 to i1 <i>; yields undefined:1</i>
%X = fptosi float 1.04E+17 to i8 <i>; yields undefined:1</i>
</pre>
</div>
<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>
+ %Y = uitofp i8 -1 to double <i>; yields double:255.0</i>
</pre>
</div>
<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>
+ %Y = sitofp i8 -1 to double <i>; yields double:-1.0</i>
</pre>
</div>
<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
+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>
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>
+are the same size, then nothing is done (<i>no-op cast</i>) other than a type
+change.</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>
+ %X = ptrtoint i32* %X to i8 <i>; yields truncation on 32-bit architecture</i>
+ %Y = ptrtoint i32* %x to i64 <i>; yields zero extension on 32-bit architecture</i>
</pre>
</div>
a pointer type, <tt>ty2</tt>.</p>
<h5>Arguments:</h5>
-<p>The '<tt>inttoptr</tt>' instruction takes an <a href="i_integer">integer</a>
+<p>The '<tt>inttoptr</tt>' instruction takes an <a href="#t_integer">integer</a>
value to cast, and a type to cast it to, which must be a
<a href="#t_pointer">pointer</a> type.
<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>
+ %X = inttoptr i32 255 to i32* <i>; yields zero extension on 64-bit architecture</i>
+ %X = inttoptr i32 255 to i32* <i>; yields no-op on 32-bit architecture</i>
+ %Y = inttoptr i64 0 to i32* <i>; yields truncation on 32-bit architecture</i>
</pre>
</div>
<h5>Example:</h5>
<pre>
- %X = bitcast i8 255 to i8 <i>; yields i8 :-1</i>
+ %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_text">
<h5>Syntax:</h5>
-<pre> <result> = icmp <cond> <ty> <var1>, <var2>
-<i>; yields {i1}:result</i>
+<pre> <result> = icmp <cond> <ty> <var1>, <var2> <i>; yields {i1}: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:
+the condition code indicating the kind of comparison to perform. It is not
+a value, just a keyword. The possible condition code are:
<ol>
<li><tt>eq</tt>: equal</li>
<li><tt>ne</tt>: not equal </li>
<tt>true</tt> if <tt>var1</tt> is less than or equal to <tt>var2</tt>.</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>
+values are compared as if they were integers.</p>
<h5>Example:</h5>
<pre> <result> = icmp eq i32 4, 5 <i>; yields: result=false</i>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
-<pre> <result> = fcmp <cond> <ty> <var1>, <var2>
-<i>; yields {i1}:result</i>
+<pre> <result> = fcmp <cond> <ty> <var1>, <var2> <i>; yields {i1}: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:
+the condition code indicating the kind of comparison to perform. It is not
+a value, just a keyword. The possible condition code are:
<ol>
<li><tt>false</tt>: no comparison, always returns false</li>
<li><tt>oeq</tt>: ordered and 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
+<p><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
<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
+<p>The type of the incoming values is 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>
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>
+<p>At runtime, the '<tt>phi</tt>' instruction logically takes on the value
+specified by the pair corresponding to the predecessor basic block that executed
+just prior to the current block.</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>
<h5>Syntax:</h5>
<pre>
- <result> = [tail] call [<a href="#callingconv">cconv</a>] <ty>* <fnptrval>(<param list>)
+ <result> = [tail] call [<a href="#callingconv">cconv</a>] <ty> [<fnty>*] <fnptrval>(<param list>)
</pre>
<h5>Overview:</h5>
href="#i_ret"><tt>ret</tt></a> instruction.
</li>
<li>
- <p>The optional "cconv" marker indicates which <a href="callingconv">calling
+ <p>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>
<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. 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>
+ <p>'<tt>ty</tt>': the type of the call instruction itself which is also
+ the type of the return value. Functions that return no value are marked
+ <tt><a href="#t_void">void</a></tt>.</p>
+ </li>
+ <li>
+ <p>'<tt>fnty</tt>': shall be the signature of the pointer to function
+ value being invoked. The argument types must match the types implied by
+ this 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
<h5>Example:</h5>
<pre>
- %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()
+ %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()
+ %Z = call void %foo(i8 97 signext)
</pre>
</div>
<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
+increments the <tt>va_list</tt> to point to the next argument. The
actual type of <tt>va_list</tt> is target specific.</p>
<h5>Semantics:</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
-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>
+well known names and semantics and are required to follow certain restrictions.
+Overall, these intrinsics represent an extension mechanism for the LLVM
+language that does not require changing all of the transformations in LLVM when
+adding to the language (or the bitcode 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
-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
-function. Additionally, because intrinsic functions are part of the LLVM
-language, it is required that they all be documented here if any are added.</p>
-
-
-<p>To learn how to add an intrinsic function, please see the <a
-href="ExtendingLLVM.html">Extending LLVM Guide</a>.
+prefix is reserved in LLVM for intrinsic names; thus, function names may not
+begin with this prefix. 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 function. Additionally, because intrinsic functions are part
+of the LLVM language, it is required if any are added that they be documented
+here.</p>
+
+<p>Some intrinsic functions can be overloaded, i.e., the intrinsic represents
+a family of functions that perform the same operation but on different data
+types. Because LLVM can represent over 8 million different integer types,
+overloading is used commonly to allow an intrinsic function to operate on any
+integer type. One or more of the argument types or the result type can be
+overloaded to accept any integer type. Argument types may also be defined as
+exactly matching a previous argument's type or the result type. This allows an
+intrinsic function which accepts multiple arguments, but needs all of them to
+be of the same type, to only be overloaded with respect to a single argument or
+the result.</p>
+
+<p>Overloaded intrinsics will have the names of its overloaded argument types
+encoded into its function name, each preceded by a period. Only those types
+which are overloaded result in a name suffix. Arguments whose type is matched
+against another type do not. For example, the <tt>llvm.ctpop</tt> function can
+take an integer of any width and returns an integer of exactly the same integer
+width. This leads to a family of functions such as
+<tt>i8 @llvm.ctpop.i8(i8 %val)</tt> and <tt>i29 @llvm.ctpop.i29(i29 %val)</tt>.
+Only one type, the return type, is overloaded, and only one type suffix is
+required. Because the argument's type is matched against the return type, it
+does not require its own name suffix.</p>
+
+<p>To learn how to add an intrinsic function, please see the
+<a href="ExtendingLLVM.html">Extending LLVM Guide</a>.
</p>
</div>
<p>All of these functions operate on arguments that use a
target-specific value type "<tt>va_list</tt>". The LLVM assembly
language reference manual does not define what this type is, so all
-transformations should be prepared to handle intrinsics with any type
-used.</p>
+transformations should be prepared to handle these functions regardless of
+the type used.</p>
<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>
+<div class="doc_code">
<pre>
-define i32 %test(i32 %X, ...) {
+define i32 @test(i32 %X, ...) {
; Initialize variable argument processing
- %ap = alloca i8 *
+ %ap = alloca i8*
%ap2 = bitcast i8** %ap to i8*
- call void %<a href="#i_va_start">llvm.va_start</a>(i8* %ap2)
+ call void @llvm.va_start(i8* %ap2)
; Read a single integer argument
- %tmp = va_arg i8 ** %ap, i32
+ %tmp = va_arg i8** %ap, i32
; Demonstrate usage of llvm.va_copy and llvm.va_end
- %aq = alloca i8 *
+ %aq = alloca i8*
%aq2 = bitcast i8** %aq to i8*
- call void %<a href="#i_va_copy">llvm.va_copy</a>(i8 *%aq2, i8* %ap2)
- call void %<a href="#i_va_end">llvm.va_end</a>(i8* %aq2)
+ call void @llvm.va_copy(i8* %aq2, i8* %ap2)
+ call void @llvm.va_end(i8* %aq2)
; Stop processing of arguments.
- call void %<a href="#i_va_end">llvm.va_end</a>(i8* %ap2)
+ call void @llvm.va_end(i8* %ap2)
ret i32 %tmp
}
+
+declare void @llvm.va_start(i8*)
+declare void @llvm.va_copy(i8*, i8*)
+declare void @llvm.va_end(i8*)
</pre>
</div>
+</div>
+
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_va_start">'<tt>llvm.va_start</tt>' Intrinsic</a>
+ <a name="int_va_start">'<tt>llvm.va_start</tt>' Intrinsic</a>
</div>
<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_list</tt> element to which the argument points, 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>
+last argument of the function as the compiler can figure that out.</p>
</div>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_va_end">'<tt>llvm.va_end</tt>' Intrinsic</a>
+ <a name="int_va_end">'<tt>llvm.va_end</tt>' Intrinsic</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
-<pre> declare void %llvm.va_end(i8* <arglist>)<br></pre>
+<pre> declare void @llvm.va_end(i8* <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>
+<p>The '<tt>llvm.va_end</tt>' intrinsic destroys <tt>*<arglist></tt>,
+which has been initialized previously with <tt><a href="#int_va_start">llvm.va_start</a></tt>
or <tt><a href="#i_va_copy">llvm.va_copy</a></tt>.</p>
<h5>Arguments:</h5>
-<p>The argument is a <tt>va_list</tt> to destroy.</p>
+<p>The argument is a pointer to a <tt>va_list</tt> to destroy.</p>
<h5>Semantics:</h5>
<p>The '<tt>llvm.va_end</tt>' intrinsic works just like the <tt>va_end</tt>
-macro available in C. In a target-dependent way, it destroys the <tt>va_list</tt>.
-Calls to <a href="#i_va_start"><tt>llvm.va_start</tt></a> and <a
- href="#i_va_copy"><tt>llvm.va_copy</tt></a> must be matched exactly
-with calls to <tt>llvm.va_end</tt>.</p>
+macro available in C. In a target-dependent way, it destroys the
+<tt>va_list</tt> element to which the argument points. Calls to <a
+href="#int_va_start"><tt>llvm.va_start</tt></a> and <a href="#int_va_copy">
+<tt>llvm.va_copy</tt></a> must be matched exactly with calls to
+<tt>llvm.va_end</tt>.</p>
</div>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_va_copy">'<tt>llvm.va_copy</tt>' Intrinsic</a>
+ <a name="int_va_copy">'<tt>llvm.va_copy</tt>' Intrinsic</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- declare void %llvm.va_copy(i8* <destarglist>, i8* <srcarglist>)
+ declare void @llvm.va_copy(i8* <destarglist>, i8* <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>
<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 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>
+<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 <tt>va_list</tt> element. This
+intrinsic is necessary because the <tt><a href="#int_va_start">
+llvm.va_start</a></tt> intrinsic may be arbitrarily complex and require, for
+example, memory allocation.</p>
</div>
<p>
LLVM support for <a href="GarbageCollection.html">Accurate Garbage
Collection</a> requires the implementation and generation of these intrinsics.
-These intrinsics allow identification of <a href="#i_gcroot">GC roots on the
+These intrinsics allow identification of <a href="#int_gcroot">GC roots on the
stack</a>, as well as garbage collector implementations that require <a
-href="#i_gcread">read</a> and <a href="#i_gcwrite">write</a> barriers.
+href="#int_gcread">read</a> and <a href="#int_gcwrite">write</a> barriers.
Front-ends for type-safe garbage collected languages should generate these
intrinsics to make use of the LLVM garbage collectors. For more details, see <a
href="GarbageCollection.html">Accurate Garbage Collection with LLVM</a>.
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_gcroot">'<tt>llvm.gcroot</tt>' Intrinsic</a>
+ <a name="int_gcroot">'<tt>llvm.gcroot</tt>' Intrinsic</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- declare void %llvm.gcroot(<ty>** %ptrloc, <ty2>* %metadata)
+ declare void @llvm.gcroot(i8** %ptrloc, i8* %metadata)
</pre>
<h5>Overview:</h5>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_gcread">'<tt>llvm.gcread</tt>' Intrinsic</a>
+ <a name="int_gcread">'<tt>llvm.gcread</tt>' Intrinsic</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- declare i8 * %llvm.gcread(i8 * %ObjPtr, i8 ** %Ptr)
+ declare i8* @llvm.gcread(i8* %ObjPtr, i8** %Ptr)
</pre>
<h5>Overview:</h5>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_gcwrite">'<tt>llvm.gcwrite</tt>' Intrinsic</a>
+ <a name="int_gcwrite">'<tt>llvm.gcwrite</tt>' Intrinsic</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- declare void %llvm.gcwrite(i8 * %P1, i8 * %Obj, i8 ** %P2)
+ declare void @llvm.gcwrite(i8* %P1, i8* %Obj, i8** %P2)
</pre>
<h5>Overview:</h5>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_returnaddress">'<tt>llvm.returnaddress</tt>' Intrinsic</a>
+ <a name="int_returnaddress">'<tt>llvm.returnaddress</tt>' Intrinsic</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- declare i8 *%llvm.returnaddress(i32 <level>)
+ declare i8 *@llvm.returnaddress(i32 <level>)
</pre>
<h5>Overview:</h5>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_frameaddress">'<tt>llvm.frameaddress</tt>' Intrinsic</a>
+ <a name="int_frameaddress">'<tt>llvm.frameaddress</tt>' Intrinsic</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- declare i8 *%llvm.frameaddress(i32 <level>)
+ declare i8 *@llvm.frameaddress(i32 <level>)
</pre>
<h5>Overview:</h5>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_stacksave">'<tt>llvm.stacksave</tt>' Intrinsic</a>
+ <a name="int_stacksave">'<tt>llvm.stacksave</tt>' Intrinsic</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- declare i8 *%llvm.stacksave()
+ declare i8 *@llvm.stacksave()
</pre>
<h5>Overview:</h5>
<p>
The '<tt>llvm.stacksave</tt>' intrinsic is used to remember the current state of
-the function stack, for use with <a href="#i_stackrestore">
+the function stack, for use with <a href="#int_stackrestore">
<tt>llvm.stackrestore</tt></a>. This is useful for implementing language
features like scoped automatic variable sized arrays in C99.
</p>
<p>
This intrinsic returns a opaque pointer value that can be passed to <a
-href="#i_stackrestore"><tt>llvm.stackrestore</tt></a>. When an
+href="#int_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
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_stackrestore">'<tt>llvm.stackrestore</tt>' Intrinsic</a>
+ <a name="int_stackrestore">'<tt>llvm.stackrestore</tt>' Intrinsic</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- declare void %llvm.stackrestore(i8 * %ptr)
+ declare void @llvm.stackrestore(i8 * %ptr)
</pre>
<h5>Overview:</h5>
<p>
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
+href="#int_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>
-See the description for <a href="#i_stacksave"><tt>llvm.stacksave</tt></a>.
+See the description for <a href="#int_stacksave"><tt>llvm.stacksave</tt></a>.
</p>
</div>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_prefetch">'<tt>llvm.prefetch</tt>' Intrinsic</a>
+ <a name="int_prefetch">'<tt>llvm.prefetch</tt>' Intrinsic</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- declare void %llvm.prefetch(i8 * <address>,
- i32 <rw>, i32 <locality>)
+ declare void @llvm.prefetch(i8* <address>, i32 <rw>, i32 <locality>)
</pre>
<h5>Overview:</h5>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_pcmarker">'<tt>llvm.pcmarker</tt>' Intrinsic</a>
+ <a name="int_pcmarker">'<tt>llvm.pcmarker</tt>' Intrinsic</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- declare void %llvm.pcmarker( i32 <id> )
+ declare void @llvm.pcmarker(i32 <id>)
</pre>
<h5>Overview:</h5>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_readcyclecounter">'<tt>llvm.readcyclecounter</tt>' Intrinsic</a>
+ <a name="int_readcyclecounter">'<tt>llvm.readcyclecounter</tt>' Intrinsic</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- declare i64 %llvm.readcyclecounter( )
+ declare i64 @llvm.readcyclecounter( )
</pre>
<h5>Overview:</h5>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_memcpy">'<tt>llvm.memcpy</tt>' Intrinsic</a>
+ <a name="int_memcpy">'<tt>llvm.memcpy</tt>' Intrinsic</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- declare void %llvm.memcpy.i32(i8 * <dest>, i8 * <src>,
+ declare void @llvm.memcpy.i32(i8 * <dest>, i8 * <src>,
i32 <len>, i32 <align>)
- declare void %llvm.memcpy.i64(i8 * <dest>, i8 * <src>,
+ declare void @llvm.memcpy.i64(i8 * <dest>, i8 * <src>,
i64 <len>, i32 <align>)
</pre>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_memmove">'<tt>llvm.memmove</tt>' Intrinsic</a>
+ <a name="int_memmove">'<tt>llvm.memmove</tt>' Intrinsic</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- declare void %llvm.memmove.i32(i8 * <dest>, i8 * <src>,
+ declare void @llvm.memmove.i32(i8 * <dest>, i8 * <src>,
i32 <len>, i32 <align>)
- declare void %llvm.memmove.i64(i8 * <dest>, i8 * <src>,
+ declare void @llvm.memmove.i64(i8 * <dest>, i8 * <src>,
i64 <len>, i32 <align>)
</pre>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_memset">'<tt>llvm.memset.*</tt>' Intrinsics</a>
+ <a name="int_memset">'<tt>llvm.memset.*</tt>' Intrinsics</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- declare void %llvm.memset.i32(i8 * <dest>, i8 <val>,
+ declare void @llvm.memset.i32(i8 * <dest>, i8 <val>,
i32 <len>, i32 <align>)
- declare void %llvm.memset.i64(i8 * <dest>, i8 <val>,
+ declare void @llvm.memset.i64(i8 * <dest>, i8 <val>,
i64 <len>, i32 <align>)
</pre>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_sqrt">'<tt>llvm.sqrt.*</tt>' Intrinsic</a>
+ <a name="int_sqrt">'<tt>llvm.sqrt.*</tt>' Intrinsic</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
+<p>This is an overloaded intrinsic. You can use <tt>llvm.sqrt</tt> on any
+floating point type. Not all targets support all types however.
<pre>
- declare float %llvm.sqrt.f32(float %Val)
- declare double %llvm.sqrt.f64(double %Val)
+ declare float @llvm.sqrt.f32(float %Val)
+ declare double @llvm.sqrt.f64(double %Val)
+ declare x86_fp80 @llvm.sqrt.f80(x86_fp80 %Val)
+ declare fp128 @llvm.sqrt.f128(fp128 %Val)
+ declare ppc_fp128 @llvm.sqrt.ppcf128(ppc_fp128 %Val)
</pre>
<h5>Overview:</h5>
<h5>Semantics:</h5>
<p>
-This function returns the sqrt of the specified operand if it is a positive
+This function returns the sqrt of the specified operand if it is a nonnegative
floating point number.
</p>
</div>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_powi">'<tt>llvm.powi.*</tt>' Intrinsic</a>
+ <a name="int_powi">'<tt>llvm.powi.*</tt>' Intrinsic</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
+<p>This is an overloaded intrinsic. You can use <tt>llvm.powi</tt> on any
+floating point type. Not all targets support all types however.
<pre>
- declare float %llvm.powi.f32(float %Val, i32 %power)
- declare double %llvm.powi.f64(double %Val, i32 %power)
+ declare float @llvm.powi.f32(float %Val, i32 %power)
+ declare double @llvm.powi.f64(double %Val, i32 %power)
+ declare x86_fp80 @llvm.powi.f80(x86_fp80 %Val, i32 %power)
+ declare fp128 @llvm.powi.f128(fp128 %Val, i32 %power)
+ declare ppc_fp128 @llvm.powi.ppcf128(ppc_fp128 %Val, i32 %power)
</pre>
<h5>Overview:</h5>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_bswap">'<tt>llvm.bswap.*</tt>' Intrinsics</a>
+ <a name="int_bswap">'<tt>llvm.bswap.*</tt>' Intrinsics</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
+<p>This is an overloaded intrinsic function. You can use bswap on any integer
+type that is an even number of bytes (i.e. BitWidth % 16 == 0).
<pre>
- declare i16 %llvm.bswap.i16(i16 <id>)
- declare i32 %llvm.bswap.i32(i32 <id>)
- declare i64 %llvm.bswap.i64(i64 <id>)
+ 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.
+The '<tt>llvm.bswap</tt>' family of intrinsics is used to byte swap integer
+values with an even number of bytes (positive multiple of 16 bits). 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
+The <tt>llvm.bswap.i16</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.
+i32 will have its bytes in 3, 2, 1, 0 order. The <tt>llvm.bswap.i48</tt>,
+<tt>llvm.bswap.i64</tt> and other intrinsics extend this concept to
+additional even-byte lengths (6 bytes, 8 bytes and more, respectively).
</p>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
+<p>This is an overloaded intrinsic. You can use llvm.ctpop on any integer bit
+width. Not all targets support all bit widths however.
<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>)
+ 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>)
+ declare i256 @llvm.ctpop.i256(i256 <src>)
</pre>
<h5>Overview:</h5>
<div class="doc_text">
<h5>Syntax:</h5>
+<p>This is an overloaded intrinsic. You can use <tt>llvm.ctlz</tt> on any
+integer bit width. Not all targets support all bit widths however.
<pre>
- 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>)
+ 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>)
+ declare i256 @llvm.ctlz.i256(i256 <src>)
</pre>
<h5>Overview:</h5>
<div class="doc_text">
<h5>Syntax:</h5>
+<p>This is an overloaded intrinsic. You can use <tt>llvm.cttz</tt> on any
+integer bit width. Not all targets support all bit widths however.
<pre>
- 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>)
+ 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>)
+ declare i256 @llvm.cttz.i256(i256 <src>)
</pre>
<h5>Overview:</h5>
</p>
</div>
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="int_part_select">'<tt>llvm.part.select.*</tt>' Intrinsic</a>
+</div>
+
+<div class="doc_text">
+
+<h5>Syntax:</h5>
+<p>This is an overloaded intrinsic. You can use <tt>llvm.part.select</tt>
+on any integer bit width.
+<pre>
+ declare i17 @llvm.part.select.i17 (i17 %val, i32 %loBit, i32 %hiBit)
+ declare i29 @llvm.part.select.i29 (i29 %val, i32 %loBit, i32 %hiBit)
+</pre>
+
+<h5>Overview:</h5>
+<p>The '<tt>llvm.part.select</tt>' family of intrinsic functions selects a
+range of bits from an integer value and returns them in the same bit width as
+the original value.</p>
+
+<h5>Arguments:</h5>
+<p>The first argument, <tt>%val</tt> and the result may be integer types of
+any bit width but they must have the same bit width. The second and third
+arguments must be <tt>i32</tt> type since they specify only a bit index.</p>
+
+<h5>Semantics:</h5>
+<p>The operation of the '<tt>llvm.part.select</tt>' intrinsic has two modes
+of operation: forwards and reverse. If <tt>%loBit</tt> is greater than
+<tt>%hiBits</tt> then the intrinsic operates in reverse mode. Otherwise it
+operates in forward mode.</p>
+<p>In forward mode, this intrinsic is the equivalent of shifting <tt>%val</tt>
+right by <tt>%loBit</tt> bits and then ANDing it with a mask with
+only the <tt>%hiBit - %loBit</tt> bits set, as follows:</p>
+<ol>
+ <li>The <tt>%val</tt> is shifted right (LSHR) by the number of bits specified
+ by <tt>%loBits</tt>. This normalizes the value to the low order bits.</li>
+ <li>The <tt>%loBits</tt> value is subtracted from the <tt>%hiBits</tt> value
+ to determine the number of bits to retain.</li>
+ <li>A mask of the retained bits is created by shifting a -1 value.</li>
+ <li>The mask is ANDed with <tt>%val</tt> to produce the result.
+</ol>
+<p>In reverse mode, a similar computation is made except that the bits are
+returned in the reverse order. So, for example, if <tt>X</tt> has the value
+<tt>i16 0x0ACF (101011001111)</tt> and we apply
+<tt>part.select(i16 X, 8, 3)</tt> to it, we get back the value
+<tt>i16 0x0026 (000000100110)</tt>.</p>
+</div>
+
+<div class="doc_subsubsection">
+ <a name="int_part_set">'<tt>llvm.part.set.*</tt>' Intrinsic</a>
+</div>
+
+<div class="doc_text">
+
+<h5>Syntax:</h5>
+<p>This is an overloaded intrinsic. You can use <tt>llvm.part.set</tt>
+on any integer bit width.
+<pre>
+ declare i17 @llvm.part.set.i17.i9 (i17 %val, i9 %repl, i32 %lo, i32 %hi)
+ declare i29 @llvm.part.set.i29.i9 (i29 %val, i9 %repl, i32 %lo, i32 %hi)
+</pre>
+
+<h5>Overview:</h5>
+<p>The '<tt>llvm.part.set</tt>' family of intrinsic functions replaces a range
+of bits in an integer value with another integer value. It returns the integer
+with the replaced bits.</p>
+
+<h5>Arguments:</h5>
+<p>The first argument, <tt>%val</tt> and the result may be integer types of
+any bit width but they must have the same bit width. <tt>%val</tt> is the value
+whose bits will be replaced. The second argument, <tt>%repl</tt> may be an
+integer of any bit width. The third and fourth arguments must be <tt>i32</tt>
+type since they specify only a bit index.</p>
+
+<h5>Semantics:</h5>
+<p>The operation of the '<tt>llvm.part.set</tt>' intrinsic has two modes
+of operation: forwards and reverse. If <tt>%lo</tt> is greater than
+<tt>%hi</tt> then the intrinsic operates in reverse mode. Otherwise it
+operates in forward mode.</p>
+<p>For both modes, the <tt>%repl</tt> value is prepared for use by either
+truncating it down to the size of the replacement area or zero extending it
+up to that size.</p>
+<p>In forward mode, the bits between <tt>%lo</tt> and <tt>%hi</tt> (inclusive)
+are replaced with corresponding bits from <tt>%repl</tt>. That is the 0th bit
+in <tt>%repl</tt> replaces the <tt>%lo</tt>th bit in <tt>%val</tt> and etc. up
+to the <tt>%hi</tt>th bit.
+<p>In reverse mode, a similar computation is made except that the bits are
+reversed. That is, the <tt>0</tt>th bit in <tt>%repl</tt> replaces the
+<tt>%hi</tt> bit in <tt>%val</tt> and etc. down to the <tt>%lo</tt>th bit.
+<h5>Examples:</h5>
+<pre>
+ llvm.part.set(0xFFFF, 0, 4, 7) -> 0xFF0F
+ llvm.part.set(0xFFFF, 0, 7, 4) -> 0xFF0F
+ llvm.part.set(0xFFFF, 1, 7, 4) -> 0xFF8F
+ llvm.part.set(0xFFFF, F, 8, 3) -> 0xFFE7
+ llvm.part.set(0xFFFF, 0, 3, 8) -> 0xFE07
+</pre>
+</div>
+
<!-- ======================================================================= -->
<div class="doc_subsection">
<a name="int_debugger">Debugger Intrinsics</a>
</div>
+<!-- ======================================================================= -->
+<div class="doc_subsection">
+ <a name="int_eh">Exception Handling Intrinsics</a>
+</div>
+
+<div class="doc_text">
+<p> The LLVM exception handling intrinsics (which all start with
+<tt>llvm.eh.</tt> prefix), are described in the <a
+href="ExceptionHandling.html#format_common_intrinsics">LLVM Exception
+Handling</a> document. </p>
+</div>
+
+<!-- ======================================================================= -->
+<div class="doc_subsection">
+ <a name="int_trampoline">Trampoline Intrinsic</a>
+</div>
+
+<div class="doc_text">
+<p>
+ This intrinsic makes it possible to excise one parameter, marked with
+ the <tt>nest</tt> attribute, from a function. The result is a callable
+ function pointer lacking the nest parameter - the caller does not need
+ to provide a value for it. Instead, the value to use is stored in
+ advance in a "trampoline", a block of memory usually allocated
+ on the stack, which also contains code to splice the nest value into the
+ argument list. This is used to implement the GCC nested function address
+ extension.
+</p>
+<p>
+ For example, if the function is
+ <tt>i32 f(i8* nest %c, i32 %x, i32 %y)</tt> then the resulting function
+ pointer has signature <tt>i32 (i32, i32)*</tt>. It can be created as follows:</p>
+<pre>
+ %tramp = alloca [10 x i8], align 4 ; size and alignment only correct for X86
+ %tramp1 = getelementptr [10 x i8]* %tramp, i32 0, i32 0
+ %p = call i8* @llvm.init.trampoline( i8* %tramp1, i8* bitcast (i32 (i8* nest , i32, i32)* @f to i8*), i8* %nval )
+ %fp = bitcast i8* %p to i32 (i32, i32)*
+</pre>
+ <p>The call <tt>%val = call i32 %fp( i32 %x, i32 %y )</tt> is then equivalent
+ to <tt>%val = call i32 %f( i8* %nval, i32 %x, i32 %y )</tt>.</p>
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="int_it">'<tt>llvm.init.trampoline</tt>' Intrinsic</a>
+</div>
+<div class="doc_text">
+<h5>Syntax:</h5>
+<pre>
+declare i8* @llvm.init.trampoline(i8* <tramp>, i8* <func>, i8* <nval>)
+</pre>
+<h5>Overview:</h5>
+<p>
+ This fills the memory pointed to by <tt>tramp</tt> with code
+ and returns a function pointer suitable for executing it.
+</p>
+<h5>Arguments:</h5>
+<p>
+ The <tt>llvm.init.trampoline</tt> intrinsic takes three arguments, all
+ pointers. The <tt>tramp</tt> argument must point to a sufficiently large
+ and sufficiently aligned block of memory; this memory is written to by the
+ intrinsic. Note that the size and the alignment are target-specific - LLVM
+ currently provides no portable way of determining them, so a front-end that
+ generates this intrinsic needs to have some target-specific knowledge.
+ The <tt>func</tt> argument must hold a function bitcast to an <tt>i8*</tt>.
+</p>
+<h5>Semantics:</h5>
+<p>
+ The block of memory pointed to by <tt>tramp</tt> is filled with target
+ dependent code, turning it into a function. A pointer to this function is
+ returned, but needs to be bitcast to an
+ <a href="#int_trampoline">appropriate function pointer type</a>
+ before being called. The new function's signature is the same as that of
+ <tt>func</tt> with any arguments marked with the <tt>nest</tt> attribute
+ removed. At most one such <tt>nest</tt> argument is allowed, and it must be
+ of pointer type. Calling the new function is equivalent to calling
+ <tt>func</tt> with the same argument list, but with <tt>nval</tt> used for the
+ missing <tt>nest</tt> argument. If, after calling
+ <tt>llvm.init.trampoline</tt>, the memory pointed to by <tt>tramp</tt> is
+ modified, then the effect of any later call to the returned function pointer is
+ undefined.
+</p>
+</div>
+
+<!-- ======================================================================= -->
+<div class="doc_subsection">
+ <a name="int_general">General Intrinsics</a>
+</div>
+
+<div class="doc_text">
+<p> This class of intrinsics is designed to be generic and has
+no specific purpose. </p>
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="int_var_annotation">'<tt>llvm.var.annotation</tt>' Intrinsic</a>
+</div>
+
+<div class="doc_text">
+
+<h5>Syntax:</h5>
+<pre>
+ declare void @llvm.var.annotation(i8* <val>, i8* <str>, i8* <str>, i32 <int> )
+</pre>
+
+<h5>Overview:</h5>
+
+<p>
+The '<tt>llvm.var.annotation</tt>' intrinsic
+</p>
+
+<h5>Arguments:</h5>
+
+<p>
+The first argument is a pointer to a value, the second is a pointer to a
+global string, the third is a pointer to a global string which is the source
+file name, and the last argument is the line number.
+</p>
+
+<h5>Semantics:</h5>
+
+<p>
+This intrinsic allows annotation of local variables with arbitrary strings.
+This can be useful for special purpose optimizations that want to look for these
+ annotations. These have no other defined use, they are ignored by code
+ generation and optimization.
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="int_annotation">'<tt>llvm.annotation.*</tt>' Intrinsic</a>
+</div>
+
+<div class="doc_text">
+
+<h5>Syntax:</h5>
+<p>This is an overloaded intrinsic. You can use '<tt>llvm.annotation</tt>' on
+any integer bit width.
+</p>
+<pre>
+ declare i8 @llvm.annotation.i8(i8 <val>, i8* <str>, i8* <str>, i32 <int> )
+ declare i16 @llvm.annotation.i16(i16 <val>, i8* <str>, i8* <str>, i32 <int> )
+ declare i32 @llvm.annotation.i32(i32 <val>, i8* <str>, i8* <str>, i32 <int> )
+ declare i64 @llvm.annotation.i64(i64 <val>, i8* <str>, i8* <str>, i32 <int> )
+ declare i256 @llvm.annotation.i256(i256 <val>, i8* <str>, i8* <str>, i32 <int> )
+</pre>
+
+<h5>Overview:</h5>
+
+<p>
+The '<tt>llvm.annotation</tt>' intrinsic.
+</p>
+
+<h5>Arguments:</h5>
+
+<p>
+The first argument is an integer value (result of some expression),
+the second is a pointer to a global string, the third is a pointer to a global
+string which is the source file name, and the last argument is the line number.
+It returns the value of the first argument.
+</p>
+
+<h5>Semantics:</h5>
+
+<p>
+This intrinsic allows annotations to be put on arbitrary expressions
+with arbitrary strings. This can be useful for special purpose optimizations
+that want to look for these annotations. These have no other defined use, they
+are ignored by code generation and optimization.
+</div>
+
<!-- *********************************************************************** -->
<hr>
<address>
projects / oota-llvm.git / blobdiff