<li><a href="#modulestructure">Module Structure</a></li>
<li><a href="#linkage">Linkage Types</a></li>
<li><a href="#callingconv">Calling Conventions</a></li>
+ <li><a href="#namedtypes">Named Types</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="#aliasstructure">Aliases</a></li>
<li><a href="#paramattrs">Parameter Attributes</a></li>
+ <li><a href="#fnattrs">Function Attributes</a></li>
<li><a href="#gc">Garbage Collector Names</a></li>
<li><a href="#moduleasm">Module-Level Inline Assembly</a></li>
<li><a href="#datalayout">Data Layout</a></li>
<li><a href="#t_opaque">Opaque Type</a></li>
</ol>
</li>
+ <li><a href="#t_uprefs">Type Up-references</a></li>
</ol>
</li>
<li><a href="#constants">Constants</a>
<ol>
- <li><a href="#simpleconstants">Simple Constants</a>
- <li><a href="#aggregateconstants">Aggregate Constants</a>
- <li><a href="#globalconstants">Global Variable and Function Addresses</a>
- <li><a href="#undefvalues">Undefined Values</a>
- <li><a href="#constantexprs">Constant Expressions</a>
+ <li><a href="#simpleconstants">Simple Constants</a></li>
+ <li><a href="#aggregateconstants">Aggregate Constants</a></li>
+ <li><a href="#globalconstants">Global Variable and Function Addresses</a></li>
+ <li><a href="#undefvalues">Undefined Values</a></li>
+ <li><a href="#constantexprs">Constant Expressions</a></li>
</ol>
</li>
<li><a href="#othervalues">Other Values</a>
<ol>
- <li><a href="#inlineasm">Inline Assembler Expressions</a>
+ <li><a href="#inlineasm">Inline Assembler Expressions</a></li>
</ol>
</li>
<li><a href="#instref">Instruction Reference</a>
<li><a href="#i_shufflevector">'<tt>shufflevector</tt>' Instruction</a></li>
</ol>
</li>
+ <li><a href="#aggregateops">Aggregate Operations</a>
+ <ol>
+ <li><a href="#i_extractvalue">'<tt>extractvalue</tt>' Instruction</a></li>
+ <li><a href="#i_insertvalue">'<tt>insertvalue</tt>' Instruction</a></li>
+ </ol>
+ </li>
<li><a href="#memoryops">Memory Access and Addressing Operations</a>
<ol>
<li><a href="#i_malloc">'<tt>malloc</tt>' Instruction</a></li>
<li><a href="#i_inttoptr">'<tt>inttoptr .. to</tt>' Instruction</a></li>
<li><a href="#i_bitcast">'<tt>bitcast .. to</tt>' Instruction</a></li>
</ol>
+ </li>
<li><a href="#otherops">Other Operations</a>
<ol>
<li><a href="#i_icmp">'<tt>icmp</tt>' Instruction</a></li>
<li><a href="#i_fcmp">'<tt>fcmp</tt>' Instruction</a></li>
+ <li><a href="#i_vicmp">'<tt>vicmp</tt>' Instruction</a></li>
+ <li><a href="#i_vfcmp">'<tt>vfcmp</tt>' Instruction</a></li>
<li><a href="#i_phi">'<tt>phi</tt>' Instruction</a></li>
<li><a href="#i_select">'<tt>select</tt>' Instruction</a></li>
<li><a href="#i_call">'<tt>call</tt>' Instruction</a></li>
<li><a href="#i_va_arg">'<tt>va_arg</tt>' Instruction</a></li>
- <li><a href="#i_getresult">'<tt>getresult</tt>' Instruction</a></li>
</ol>
</li>
</ol>
<li><a href="#int_it">'<tt>llvm.init.trampoline</tt>' Intrinsic</a></li>
</ol>
</li>
- <li><a href="#int_atomics">Atomic intrinsics</a>
- <ol>
- <li><a href="#int_memory_barrier"><tt>llvm.memory_barrier</tt></a></li>
- <li><a href="#int_atomic_lcs"><tt>llvm.atomic.lcs</tt></a></li>
- <li><a href="#int_atomic_las"><tt>llvm.atomic.las</tt></a></li>
- <li><a href="#int_atomic_swap"><tt>llvm.atomic.swap</tt></a></li>
- </ol>
- </li>
+ <li><a href="#int_atomics">Atomic intrinsics</a>
+ <ol>
+ <li><a href="#int_memory_barrier"><tt>llvm.memory_barrier</tt></a></li>
+ <li><a href="#int_atomic_cmp_swap"><tt>llvm.atomic.cmp.swap</tt></a></li>
+ <li><a href="#int_atomic_swap"><tt>llvm.atomic.swap</tt></a></li>
+ <li><a href="#int_atomic_load_add"><tt>llvm.atomic.load.add</tt></a></li>
+ <li><a href="#int_atomic_load_sub"><tt>llvm.atomic.load.sub</tt></a></li>
+ <li><a href="#int_atomic_load_and"><tt>llvm.atomic.load.and</tt></a></li>
+ <li><a href="#int_atomic_load_nand"><tt>llvm.atomic.load.nand</tt></a></li>
+ <li><a href="#int_atomic_load_or"><tt>llvm.atomic.load.or</tt></a></li>
+ <li><a href="#int_atomic_load_xor"><tt>llvm.atomic.load.xor</tt></a></li>
+ <li><a href="#int_atomic_load_max"><tt>llvm.atomic.load.max</tt></a></li>
+ <li><a href="#int_atomic_load_min"><tt>llvm.atomic.load.min</tt></a></li>
+ <li><a href="#int_atomic_load_umax"><tt>llvm.atomic.load.umax</tt></a></li>
+ <li><a href="#int_atomic_load_umin"><tt>llvm.atomic.load.umin</tt></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>
+ '<tt>llvm.var.annotation</tt>' Intrinsic</a></li>
<li><a href="#int_annotation">
- <tt>llvm.annotation.*</tt>' Intrinsic</a></li>
+ '<tt>llvm.annotation.*</tt>' Intrinsic</a></li>
<li><a href="#int_trap">
- <tt>llvm.trap</tt>' Intrinsic</a></li>
+ '<tt>llvm.trap</tt>' Intrinsic</a></li>
+ <li><a href="#int_stackprotector">
+ '<tt>llvm.stackprotector</tt>' Intrinsic</a></li>
</ol>
</li>
</ol>
<div class="doc_text">
<p>This document is a reference manual for the LLVM assembly language.
-LLVM is an SSA based representation that provides type safety,
-low-level operations, flexibility, and the capability of representing
-'all' high-level languages cleanly. It is the common code
+LLVM is a Static Single Assignment (SSA) based representation that provides
+type safety, low-level operations, flexibility, and the capability of
+representing 'all' high-level languages cleanly. It is the common code
representation used throughout all phases of the LLVM compilation
strategy.</p>
</div>
<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:
+ there are three different formats for identifiers, for different purposes:</p>
<ol>
<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 named value.</li>
+ with quotes. Special characters may be escaped using "\xx" where xx is the
+ ASCII code for the character in hexadecimal. In this way, any character can
+ be used in a name value, even quotes themselves.
<li>Unnamed values are represented as an unsigned numeric value with their
prefix. For example, %12, @2, %44.</li>
<i>; Definition of main function</i>
define i32 @main() { <i>; i32()* </i>
- <i>; Convert [13x i8 ]* to i8 *...</i>
+ <i>; Convert [13 x 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
<dl>
- <dt><tt><b><a name="linkage_internal">internal</a></b></tt> </dt>
+ <dt><tt><b><a name="linkage_private">private</a></b></tt>: </dt>
- <dd>Global values with internal linkage are only directly accessible by
+ <dd>Global values with private linkage are only directly accessible by
objects in the current module. In particular, linking code into a module with
- an internal global value may cause the internal to be renamed as necessary to
- avoid collisions. Because the symbol is internal to the module, all
- references can be updated. This corresponds to the notion of the
+ an private global value may cause the private to be renamed as necessary to
+ avoid collisions. Because the symbol is private to the module, all
+ references can be updated. This doesn't show up in any symbol table in the
+ object file.
+ </dd>
+
+ <dt><tt><b><a name="linkage_internal">internal</a></b></tt>: </dt>
+
+ <dd> Similar to private, but the value shows as a local symbol (STB_LOCAL in
+ the case of ELF) in the object file. This corresponds to the notion of the
'<tt>static</tt>' keyword in C.
</dd>
allowed to be discarded.
</dd>
+ <dt><tt><b><a name="linkage_common">common</a></b></tt>: </dt>
+
+ <dd>"<tt>common</tt>" linkage is exactly the same as <tt>linkonce</tt>
+ linkage, except that unreferenced <tt>common</tt> globals may not be
+ discarded. This is used for globals that may be emitted in multiple
+ translation units, but that are not guaranteed to be emitted into every
+ translation unit that uses them. One example of this is tentative
+ definitions in C, such as "<tt>int X;</tt>" at global scope.
+ </dd>
+
<dt><tt><b><a name="linkage_weak">weak</a></b></tt>: </dt>
- <dd>"<tt>weak</tt>" linkage is exactly the same as <tt>linkonce</tt> linkage,
- except that unreferenced <tt>weak</tt> globals may not be discarded. This is
- used for globals that may be emitted in multiple translation units, but that
- are not guaranteed to be emitted into every translation unit that uses them.
- One example of this are common globals in C, such as "<tt>int X;</tt>" at
- global scope.
+ <dd>"<tt>weak</tt>" linkage is the same as <tt>common</tt> linkage, except
+ that some targets may choose to emit different assembly sequences for them
+ for target-dependent reasons. This is used for globals that are declared
+ "weak" in C source code.
</dd>
<dt><tt><b><a name="linkage_appending">appending</a></b></tt>: </dt>
</dd>
<dt><tt><b><a name="linkage_externweak">extern_weak</a></b></tt>: </dt>
- <dd>The semantics of this linkage follow the ELF model: the symbol is weak
- until linked, if not linked, the symbol becomes null instead of being an
- undefined reference.
+ <dd>The semantics of this linkage follow the ELF object file model: the
+ symbol is weak until linked, if not linked, the symbol becomes null instead
+ of being an undefined reference.
</dd>
<dt><tt><b><a name="linkage_external">externally visible</a></b></tt>:</dt>
<p>
The next two types of linkage are targeted for Microsoft Windows platform
only. They are designed to support importing (exporting) symbols from (to)
- DLLs.
+ DLLs (Dynamic Link Libraries).
</p>
<dl>
<dd>"<tt>dllimport</tt>" linkage causes the compiler to reference a function
or variable via a global pointer to a pointer that is set up by the DLL
exporting the symbol. On Microsoft Windows targets, the pointer name is
- formed by combining <code>_imp__</code> and the function or variable name.
+ formed by combining <code>__imp_</code> and the function or variable name.
</dd>
<dt><tt><b><a name="linkage_dllexport">dllexport</a></b></tt>: </dt>
<dd>"<tt>dllexport</tt>" linkage causes the compiler to provide a global
pointer to a pointer in a DLL, so that it can be referenced with the
<tt>dllimport</tt> attribute. On Microsoft Windows targets, the pointer
- name is formed by combining <code>_imp__</code> and the function or variable
+ name is formed by combining <code>__imp_</code> and the function or variable
name.
</dd>
</dl>
-<p><a name="linkage_external"></a>For example, since the "<tt>.LC0</tt>"
+<p>For example, since the "<tt>.LC0</tt>"
variable is defined to be internal, if another module defined a "<tt>.LC0</tt>"
variable and was linked with this one, one of the two would be renamed,
preventing a collision. Since "<tt>main</tt>" and "<tt>puts</tt>" are
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.
+linkages.</p>
</div>
<!-- ======================================================================= -->
<dd>This calling convention attempts to make calls as fast as possible
(e.g. by passing things in registers). This calling convention allows the
target to use whatever tricks it wants to produce fast code for the target,
- without having to conform to an externally specified ABI. Implementations of
- this convention should allow arbitrary tail call optimization to be supported.
- This calling convention does not support varargs and requires the prototype of
- all callees to exactly match the prototype of the function definition.
+ without having to conform to an externally specified ABI (Application Binary
+ Interface). Implementations of this convention should allow arbitrary
+ <a href="CodeGenerator.html#tailcallopt">tail call optimization</a> to be
+ supported. This calling convention does not support varargs and requires the
+ prototype of all callees to exactly match the prototype of the function
+ definition.
</dd>
<dt><b>"<tt>coldcc</tt>" - The cold calling convention</b>:</dt>
<dl>
<dt><b>"<tt>default</tt>" - Default style</b>:</dt>
- <dd>On ELF, default visibility means that the declaration is visible to other
+ <dd>On targets that use the ELF object file format, default visibility means
+ that the declaration is visible to other
modules and, in shared libraries, means that the declared entity may be
overridden. On Darwin, default visibility means that the declaration is
visible to other modules. Default visibility corresponds to "external
</div>
+<!-- ======================================================================= -->
+<div class="doc_subsection">
+ <a name="namedtypes">Named Types</a>
+</div>
+
+<div class="doc_text">
+
+<p>LLVM IR allows you to specify name aliases for certain types. This can make
+it easier to read the IR and make the IR more condensed (particularly when
+recursive types are involved). An example of a name specification is:
+</p>
+
+<div class="doc_code">
+<pre>
+%mytype = type { %mytype*, i32 }
+</pre>
+</div>
+
+<p>You may give a name to any <a href="#typesystem">type</a> except "<a
+href="t_void">void</a>". Type name aliases may be used anywhere a type is
+expected with the syntax "%mytype".</p>
+
+<p>Note that type names are aliases for the structural type that they indicate,
+and that you can therefore specify multiple names for the same type. This often
+leads to confusing behavior when dumping out a .ll file. Since LLVM IR uses
+structural typing, the name is not part of the type. When printing out LLVM IR,
+the printer will pick <em>one name</em> to render all types of a particular
+shape. This means that if you have code where two different source types end up
+having the same LLVM type, that the dumper will sometimes print the "wrong" or
+unexpected type. This is an important design point and isn't going to
+change.</p>
+
+</div>
+
<!-- ======================================================================= -->
<div class="doc_subsection">
<a name="globalvars">Global Variables</a>
<div class="doc_code">
<pre>
-@G = constant float 1.0 addrspace(5), section "foo", align 4
+@G = addrspace(5) constant float 1.0, section "foo", align 4
</pre>
</div>
<a href="#callingconv">calling convention</a>, a return type, an optional
<a href="#paramattrs">parameter attribute</a> for the return type, a function
name, a (possibly empty) argument list (each with optional
-<a href="#paramattrs">parameter attributes</a>), an optional section, an
-optional alignment, an optional <a href="#gc">garbage collector name</a>, an
-opening curly brace, a list of basic blocks, and a closing curly brace.
+<a href="#paramattrs">parameter attributes</a>), optional
+<a href="#fnattrs">function attributes</a>, an optional section,
+an optional alignment, an optional <a href="#gc">garbage collector name</a>,
+an opening curly brace, a list of basic blocks, and a closing curly brace.
LLVM function declarations consist of the "<tt>declare</tt>" keyword, an
optional <a href="#linkage">linkage type</a>, an optional
name, a possibly empty list of arguments, an optional alignment, and an optional
<a href="#gc">garbage collector name</a>.</p>
-<p>A function definition contains a list of basic blocks, forming the CFG for
+<p>A function definition contains a list of basic blocks, forming the CFG
+(Control Flow Graph) for
the function. Each basic block may optionally start with a label (giving the
basic block a symbol table entry), contains a list of instructions, and ends
with a <a href="#terminators">terminator</a> instruction (such as a branch or
function is forced to have at least that much alignment. All alignments must be
a power of 2.</p>
+ <h5>Syntax:</h5>
+
+<div class="doc_code">
+<tt>
+define [<a href="#linkage">linkage</a>] [<a href="#visibility">visibility</a>]
+ [<a href="#callingconv">cconv</a>] [<a href="#paramattrs">ret attrs</a>]
+ <ResultType> @<FunctionName> ([argument list])
+ [<a href="#fnattrs">fn Attrs</a>] [section "name"] [align N]
+ [<a href="#gc">gc</a>] { ... }
+</tt>
+</div>
+
</div>
<div class="doc_code">
<pre>
-@<Name> = [Linkage] [Visibility] alias <AliaseeTy> @<Aliasee>
+@<Name> = alias [Linkage] [Visibility] <AliaseeTy> @<Aliasee>
</pre>
</div>
<div class="doc_code">
<pre>
-declare i32 @printf(i8* noalias , ...) nounwind
-declare i32 @atoi(i8*) nounwind readonly
+declare i32 @printf(i8* noalias , ...)
+declare i32 @atoi(i8 zeroext)
+declare signext i8 @returns_signed_char()
</pre>
</div>
<p>Currently, only the following parameter attributes are defined:</p>
<dl>
<dt><tt>zeroext</tt></dt>
- <dd>This indicates that the parameter should be zero extended just before
- a call to this function.</dd>
+ <dd>This indicates to the code generator that the parameter or return value
+ should be zero-extended to a 32-bit value by the caller (for a parameter)
+ or the callee (for a return value).</dd>
<dt><tt>signext</tt></dt>
- <dd>This indicates that the parameter should be sign extended just before
- a call to this function.</dd>
+ <dd>This indicates to the code generator that the parameter or return value
+ should be sign-extended to a 32-bit value by the caller (for a parameter)
+ or the callee (for a return value).</dd>
<dt><tt>inreg</tt></dt>
- <dd>This indicates that the parameter should be placed in register (if
- possible) during assembling function call. Support for this attribute is
- target-specific</dd>
+ <dd>This indicates that this parameter or return value should be treated
+ in a special target-dependent fashion during while emitting code for a
+ function call or return (usually, by putting it in a register as opposed
+ to memory, though some targets use it to distinguish between two different
+ kinds of registers). Use of this attribute is target-specific.</dd>
- <dt><tt>byval</tt></dt>
+ <dt><tt><a name="byval">byval</a></tt></dt>
<dd>This indicates that the pointer parameter should really be passed by
value to the function. The attribute implies that a hidden copy of the
pointee is made between the caller and the callee, so the callee is unable
- to modify the value in the callee. This attribute is only valid on llvm
+ to modify the value in the callee. This attribute is only valid on LLVM
pointer arguments. It is generally used to pass structs and arrays by
- value, but is also valid on scalars (even though this is silly).</dd>
+ value, but is also valid on pointers to scalars. The copy is considered to
+ belong to the caller not the callee (for example,
+ <tt><a href="#readonly">readonly</a></tt> functions should not write to
+ <tt>byval</tt> parameters). This is not a valid attribute for return
+ values. </dd>
<dt><tt>sret</tt></dt>
<dd>This indicates that the pointer parameter specifies the address of a
structure that is the return value of the function in the source program.
- Loads and stores to the structure are assumed not to trap.
- May only be applied to the first parameter.</dd>
+ This pointer must be guaranteed by the caller to be valid: loads and stores
+ to the structure may be assumed by the callee to not to trap. This may only
+ be applied to the first parameter. This is not a valid attribute for
+ return values. </dd>
<dt><tt>noalias</tt></dt>
- <dd>This indicates that the parameter does not alias any global or any other
- parameter. The caller is responsible for ensuring that this is the case,
- usually by placing the value in a stack allocation.</dd>
-
- <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 no exceptions unwind out of the
- function. Usually this is because the function makes no use of exceptions,
- but it may also be that the function catches any exceptions thrown when
- executing it.</dd>
+ <dd>This indicates that the pointer does not alias any global or any other
+ parameter. The caller is responsible for ensuring that this is the
+ case. On a function return value, <tt>noalias</tt> additionally indicates
+ that the pointer does not alias any other pointers visible to the
+ caller. For further details, please see the discussion of the NoAlias
+ response in
+ <a href="http://llvm.org/docs/AliasAnalysis.html#MustMayNo">alias
+ analysis</a>.</dd>
+
+ <dt><tt>nocapture</tt></dt>
+ <dd>This indicates that the callee does not make any copies of the pointer
+ that outlive the callee itself. This is not a valid attribute for return
+ values.</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>
- <dt><tt>readonly</tt></dt>
- <dd>This function attribute indicates that the function has no side-effects
- except for producing a return value or throwing an exception. The value
- returned must only depend on the function arguments and/or global variables.
- It may use values obtained by dereferencing pointers.</dd>
- <dt><tt>readnone</tt></dt>
- <dd>A <tt>readnone</tt> function has the same restrictions as a <tt>readonly</tt>
- function, but in addition it is not allowed to dereference any pointer arguments
- or global variables.
+ <dd>This indicates that the pointer parameter can be excised using the
+ <a href="#int_trampoline">trampoline intrinsics</a>. This is not a valid
+ attribute for return values.</dd>
</dl>
</div>
the named garbage collection algorithm.</p>
</div>
+<!-- ======================================================================= -->
+<div class="doc_subsection">
+ <a name="fnattrs">Function Attributes</a>
+</div>
+
+<div class="doc_text">
+
+<p>Function attributes are set to communicate additional information about
+ a function. Function attributes are considered to be part of the function,
+ not of the function type, so functions with different parameter attributes
+ can have the same function type.</p>
+
+ <p>Function attributes are simple keywords that follow the type specified. If
+ multiple attributes are needed, they are space separated. For
+ example:</p>
+
+<div class="doc_code">
+<pre>
+define void @f() noinline { ... }
+define void @f() alwaysinline { ... }
+define void @f() alwaysinline optsize { ... }
+define void @f() optsize
+</pre>
+</div>
+
+<dl>
+<dt><tt>alwaysinline</tt></dt>
+<dd>This attribute indicates that the inliner should attempt to inline this
+function into callers whenever possible, ignoring any active inlining size
+threshold for this caller.</dd>
+
+<dt><tt>noinline</tt></dt>
+<dd>This attribute indicates that the inliner should never inline this function
+in any situation. This attribute may not be used together with the
+<tt>alwaysinline</tt> attribute.</dd>
+
+<dt><tt>optsize</tt></dt>
+<dd>This attribute suggests that optimization passes and code generator passes
+make choices that keep the code size of this function low, and otherwise do
+optimizations specifically to reduce code size.</dd>
+
+<dt><tt>noreturn</tt></dt>
+<dd>This function attribute indicates that the function never returns normally.
+This produces undefined behavior at runtime if the function ever does
+dynamically return.</dd>
+
+<dt><tt>nounwind</tt></dt>
+<dd>This function attribute indicates that the function never returns with an
+unwind or exceptional control flow. If the function does unwind, its runtime
+behavior is undefined.</dd>
+
+<dt><tt>readnone</tt></dt>
+<dd>This attribute indicates that the function computes its result (or the
+exception it throws) based strictly on its arguments, without dereferencing any
+pointer arguments or otherwise accessing any mutable state (e.g. memory, control
+registers, etc) visible to caller functions. It does not write through any
+pointer arguments (including <tt><a href="#byval">byval</a></tt> arguments) and
+never changes any state visible to callers.</dd>
+
+<dt><tt><a name="readonly">readonly</a></tt></dt>
+<dd>This attribute indicates that the function does not write through any
+pointer arguments (including <tt><a href="#byval">byval</a></tt> arguments)
+or otherwise modify any state (e.g. memory, control registers, etc) visible to
+caller functions. It may dereference pointer arguments and read state that may
+be set in the caller. A readonly function always returns the same value (or
+throws the same exception) when called with the same set of arguments and global
+state.</dd>
+
+<dt><tt><a name="ssp">ssp</a></tt></dt>
+<dd>This attribute indicates that the function should emit a stack smashing
+protector. It is in the form of a "canary"—a random value placed on the
+stack before the local variables that's checked upon return from the function to
+see if it has been overwritten. A heuristic is used to determine if a function
+needs stack protectors or not.
+
+<p>If a function that has an <tt>ssp</tt> attribute is inlined into a function
+that doesn't have an <tt>ssp</tt> attribute, then the resulting function will
+have an <tt>ssp</tt> attribute.</p></dd>
+
+<dt><tt>sspreq</tt></dt>
+<dd>This attribute indicates that the function should <em>always</em> emit a
+stack smashing protector. This overrides the <tt><a href="#ssp">ssp</a></tt>
+function attribute.
+
+<p>If a function that has an <tt>sspreq</tt> attribute is inlined into a
+function that doesn't have an <tt>sspreq</tt> attribute or which has
+an <tt>ssp</tt> attribute, then the resulting function will have
+an <tt>sspreq</tt> attribute.</p></dd>
+</dl>
+
+</div>
+
<!-- ======================================================================= -->
<div class="doc_subsection">
<a name="moduleasm">Module-Level Inline Assembly</a>
<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,
+ <dd>Specifies that the 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
<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
+ <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>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:
+<p>When LLVM is determining the alignment for a given type, it uses the
+following rules:</p>
<ol>
<li>If the type sought is an exact match for one of the specifications, that
specification is used.</li>
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>
+ 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>
<p>The LLVM type system is one of the most important features of the
intermediate representation. Being typed enables a number of
-optimizations to be performed on the IR directly, without having to do
+optimizations to be performed on the intermediate representation directly,
+without having to do
extra analyses on the side before the transformation. A strong type
system makes it easier to read the generated code and enables novel
analyses and transformations that are not feasible to perform on normal
<td><a href="#t_integer">integer</a>,
<a href="#t_floating">floating point</a>,
<a href="#t_pointer">pointer</a>,
- <a href="#t_vector">vector</a>
+ <a href="#t_vector">vector</a>,
+ <a href="#t_struct">structure</a>,
+ <a href="#t_array">array</a>,
+ <a href="#t_label">label</a>.
</td>
</tr>
<tr>
<td><a href="#t_primitive">primitive</a></td>
<td><a href="#t_label">label</a>,
<a href="#t_void">void</a>,
- <a href="#t_integer">integer</a>,
<a href="#t_floating">floating point</a>.</td>
</tr>
<tr>
<a href="#t_pstruct">packed structure</a>,
<a href="#t_vector">vector</a>,
<a href="#t_opaque">opaque</a>.
+ </td>
</tr>
</tbody>
</table>
<p>The <a href="#t_firstclass">first class</a> types are perhaps the
most important. Values of these types are the only ones which can be
produced by instructions, passed as arguments, or used as operands to
-instructions. This means that all structures and arrays must be
-manipulated either by pointer or by component.</p>
+instructions.</p>
</div>
<!-- ======================================================================= -->
</tr>
</tbody>
</table>
+
+<p>Note that the code generator does not yet support large integer types
+to be used as function return types. The specific limit on how large a
+return type the code generator can currently handle is target-dependent;
+currently it's often 64 bits for 32-bit targets and 128 bits for 64-bit
+targets.</p>
+
</div>
<!-- _______________________________________________________________________ -->
length. This allows implementation of 'pascal style arrays' with the LLVM
type "{ i32, [0 x float]}", for example.</p>
+<p>Note that the code generator does not yet support large aggregate types
+to be used as function return types. The specific limit on how large an
+aggregate return type the code generator can currently handle is
+target-dependent, and also dependent on the aggregate element types.</p>
+
</div>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection"> <a name="t_function">Function Type</a> </div>
<div class="doc_text">
+
<h5>Overview:</h5>
+
<p>The function type can be thought of as a function signature. It
consists of a return type and a list of formal parameter types. The
-return type of a function type is a scalar type or a void type or a struct type.
+return type of a function type is a scalar type, a void type, or a struct type.
If the return type is a struct type then all struct elements must be of first
-class types. Function types are usually used to build virtual function tables
-(which are structures of pointers to functions), for indirect function
-calls, and when defining a function.</p>
+class types, and the struct must have at least one element.</p>
<h5>Syntax:</h5>
-<pre> <returntype list> (<parameter list>)<br></pre>
+
+<pre>
+ <returntype list> (<parameter list>)
+</pre>
+
<p>...where '<tt><parameter list></tt>' is a comma-separated list of type
specifiers. Optionally, the parameter list may include a type <tt>...</tt>,
which indicates that the function takes a variable number of arguments.
href="#int_varargs">variable argument handling intrinsic</a> functions.
'<tt><returntype list></tt>' is a comma-separated list of
<a href="#t_firstclass">first class</a> type specifiers.</p>
+
<h5>Examples:</h5>
<table class="layout">
<tr class="layout">
</td>
</tr><tr class="layout">
<td class="left"><tt>{i32, i32} (i32)</tt></td>
- <td class="left">A function taking an <tt>i32></tt>, returning two
- <tt> i32 </tt> values as an aggregate of type <tt>{ i32, i32 }</tt>
+ <td class="left">A function taking an <tt>i32</tt>, returning two
+ <tt>i32</tt> values as an aggregate of type <tt>{ i32, i32 }</tt>
</td>
</tr>
</table>
an <tt>i32</tt>.</td>
</tr>
</table>
+
+<p>Note that the code generator does not yet support large aggregate types
+to be used as function return types. The specific limit on how large an
+aggregate return type the code generator can currently handle is
+target-dependent, and also dependent on the aggregate element types.</p>
+
</div>
<!-- _______________________________________________________________________ -->
<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">
+<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
<h5>Examples:</h5>
<table class="layout">
<tr class="layout">
- <td class="left"><tt>[4x i32]*</tt></td>
+ <td class="left"><tt>[4 x i32]*</tt></td>
<td class="left">A <a href="#t_pointer">pointer</a> to <a
href="#t_array">array</a> of four <tt>i32</tt> values.</td>
</tr>
<td class="left">Vector of 2 64-bit integer values.</td>
</tr>
</table>
+
+<p>Note that the code generator does not yet support large vector types
+to be used as function return types. The specific limit on how large a
+vector return type codegen can currently handle is target-dependent;
+currently it's often a few times longer than a hardware vector register.</p>
+
</div>
<!-- _______________________________________________________________________ -->
</table>
</div>
+<!-- ======================================================================= -->
+<div class="doc_subsection">
+ <a name="t_uprefs">Type Up-references</a>
+</div>
+
+<div class="doc_text">
+<h5>Overview:</h5>
+<p>
+An "up reference" allows you to refer to a lexically enclosing type without
+requiring it to have a name. For instance, a structure declaration may contain a
+pointer to any of the types it is lexically a member of. Example of up
+references (with their equivalent as named type declarations) include:</p>
+
+<pre>
+ { \2 * } %x = type { %t* }
+ { \2 }* %y = type { %y }*
+ \1* %z = type %z*
+</pre>
+
+<p>
+An up reference is needed by the asmprinter for printing out cyclic types when
+there is no declared name for a type in the cycle. Because the asmprinter does
+not want to print out an infinite type string, it needs a syntax to handle
+recursive types that have no names (all names are optional in llvm IR).
+</p>
+
+<h5>Syntax:</h5>
+<pre>
+ \<level>
+</pre>
+
+<p>
+The level is the count of the lexical type that is being referred to.
+</p>
+
+<h5>Examples:</h5>
+
+<table class="layout">
+ <tr class="layout">
+ <td class="left"><tt>\1*</tt></td>
+ <td class="left">Self-referential pointer.</td>
+ </tr>
+ <tr class="layout">
+ <td class="left"><tt>{ { \3*, i8 }, i32 }</tt></td>
+ <td class="left">Recursive structure where the upref refers to the out-most
+ structure.</td>
+ </tr>
+</table>
+</div>
+
<!-- *********************************************************************** -->
<div class="doc_section"> <a name="constants">Constants</a> </div>
<dd>Floating point constants use standard decimal notation (e.g. 123.421),
exponential notation (e.g. 1.23421e+2), or a more precise hexadecimal
- notation (see below). Floating point constants must have a <a
- href="#t_floating">floating point</a> type. </dd>
+ notation (see below). The assembler requires the exact decimal value of
+ a floating-point constant. For example, the assembler accepts 1.25 but
+ rejects 1.3 because 1.3 is a repeating decimal in binary. Floating point
+ constants must have a <a href="#t_floating">floating point</a> type. </dd>
<dt><b>Null pointer constants</b></dt>
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
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.
+ pointers it is only valid to cast to another pointer type. It is not valid
+ to bitcast to or from an aggregate type.
</dd>
<dt><b><tt>getelementptr ( CSTPTR, IDX0, IDX1, ... )</tt></b></dt>
<dt><b><tt>fcmp COND ( VAL1, VAL2 )</tt></b></dt>
<dd>Performs the <a href="#i_fcmp">fcmp operation</a> on constants.</dd>
+ <dt><b><tt>vicmp COND ( VAL1, VAL2 )</tt></b></dt>
+ <dd>Performs the <a href="#i_vicmp">vicmp operation</a> on constants.</dd>
+
+ <dt><b><tt>vfcmp COND ( VAL1, VAL2 )</tt></b></dt>
+ <dd>Performs the <a href="#i_vfcmp">vfcmp operation</a> on constants.</dd>
+
<dt><b><tt>extractelement ( VAL, IDX )</tt></b></dt>
<dd>Perform the <a href="#i_extractelement">extractelement
- operation</a> on constants.
+ operation</a> on constants.</dd>
<dt><b><tt>insertelement ( VAL, ELT, IDX )</tt></b></dt>
<p>TODO: The format of the asm and constraints string still need to be
documented here. Constraints on what can be done (e.g. duplication, moving, etc
-need to be documented).
+need to be documented). This is probably best done by reference to another
+document that covers inline asm from a holistic perspective.
</p>
</div>
Instruction</a> </div>
<div class="doc_text">
<h5>Syntax:</h5>
-<pre> ret <type> <value> <i>; Return a value from a non-void function</i>
+<pre>
+ ret <type> <value> <i>; Return a value from a non-void function</i>
ret void <i>; Return from void function</i>
- ret <type> <value>, <type> <value> <i>; Return two values from a non-void function </i>
</pre>
+
<h5>Overview:</h5>
-<p>The '<tt>ret</tt>' instruction is used to return control flow (and a
-value) from a function back to the caller.</p>
+
+<p>The '<tt>ret</tt>' instruction is used to return control flow (and
+optionally a value) from a function back to the caller.</p>
<p>There are two forms of the '<tt>ret</tt>' instruction: one that
returns a value and then causes control flow, and one that just causes
control flow to occur.</p>
+
<h5>Arguments:</h5>
-<p>The '<tt>ret</tt>' instruction may return one or multiple values. The
-type of each return value must be a '<a href="#t_firstclass">first class</a>'
- type. Note that a function is not <a href="#wellformed">well formed</a>
-if there exists a '<tt>ret</tt>' instruction inside of the function that
-returns values that do not match the return type of the function.</p>
+
+<p>The '<tt>ret</tt>' instruction optionally accepts a single argument,
+the return value. The type of the return value must be a
+'<a href="#t_firstclass">first class</a>' type.</p>
+
+<p>A function is not <a href="#wellformed">well formed</a> if
+it it has a non-void return type and contains a '<tt>ret</tt>'
+instruction with no return value or a return value with a type that
+does not match its type, or if it has a void return type and contains
+a '<tt>ret</tt>' instruction with a return value.</p>
+
<h5>Semantics:</h5>
+
<p>When the '<tt>ret</tt>' instruction is executed, control flow
returns back to the calling function's context. If the caller is a "<a
href="#i_call"><tt>call</tt></a>" instruction, execution continues at
href="#i_invoke"><tt>invoke</tt></a>" instruction, execution continues
at the beginning of the "normal" destination block. If the instruction
returns a value, that value shall set the call or invoke instruction's
-return value. If the instruction returns multiple values then these
-values can only be accessed through a '<a href="#i_getresult"><tt>getresult</tt>
-</a>' instruction.</p>
+return value.</p>
+
<h5>Example:</h5>
-<pre> ret i32 5 <i>; Return an integer value of 5</i>
+
+<pre>
+ ret i32 5 <i>; Return an integer value of 5</i>
ret void <i>; Return from a void function</i>
- ret i32 4, i8 2 <i>; Return two values 4 and 2 </i>
+ ret { i32, i8 } { i32 4, i8 2 } <i>; Return an aggregate of values 4 and 2</i>
</pre>
+
+<p>Note that the code generator does not yet fully support large
+ return values. The specific sizes that are currently supported are
+ dependent on the target. For integers, on 32-bit targets the limit
+ is often 64 bits, and on 64-bit targets the limit is often 128 bits.
+ For aggregate types, the current limits are dependent on the element
+ types; for example targets are often limited to 2 total integer
+ elements and 2 total floating-point elements.</p>
+
</div>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection"> <a name="i_br">'<tt>br</tt>' Instruction</a> </div>
<pre>
<i>; Emulate a conditional br instruction</i>
%Val = <a href="#i_zext">zext</a> i1 %value to i32
- switch i32 %Val, label %truedest [i32 0, label %falsedest ]
+ switch i32 %Val, label %truedest [ i32 0, label %falsedest ]
<i>; Emulate an unconditional br instruction</i>
switch i32 0, label %dest [ ]
<i>; Implement a jump table:</i>
- switch i32 %val, label %otherwise [ i32 0, label %onzero
- i32 1, label %onone
- i32 2, label %ontwo ]
+ switch i32 %val, label %otherwise [ i32 0, label %onzero
+ i32 1, label %onone
+ i32 2, label %ontwo ]
</pre>
</div>
<h5>Syntax:</h5>
<pre>
- <result> = invoke [<a href="#callingconv">cconv</a>] <ptr to function ty> <function ptr val>(<function args>)
+ <result> = invoke [<a href="#callingconv">cconv</a>] [<a href="#paramattrs">ret attrs</a>] <ptr to function ty> <function ptr val>(<function args>) [<a href="#fnattrs">fn attrs</a>]
to label <normal label> unwind label <exception label>
</pre>
"<tt><a href="#i_ret">ret</a></tt>" instruction, control flow will return to the
"normal" label. If the callee (or any indirect callees) returns with the "<a
href="#i_unwind"><tt>unwind</tt></a>" instruction, control is interrupted and
-continued at the dynamically nearest "exception" label. If the callee function
-returns multiple values then individual return values are only accessible through
-a '<tt><a href="#i_getresult">getresult</a></tt>' instruction.</p>
+continued at the dynamically nearest "exception" label.</p>
<h5>Arguments:</h5>
convention</a> the call should use. If none is specified, the call defaults
to using C calling conventions.
</li>
+
+ <li>The optional <a href="#paramattrs">Parameter Attributes</a> list for
+ return values. Only '<tt>zeroext</tt>', '<tt>signext</tt>',
+ and '<tt>inreg</tt>' attributes are valid here.</li>
+
<li>'<tt>ptr to function ty</tt>': shall be the signature of the pointer to
function value being invoked. In most cases, this is a direct function
invocation, but indirect <tt>invoke</tt>s are just as possible, branching off
<li>'<tt>exception label</tt>': the label reached when a callee returns with
the <a href="#i_unwind"><tt>unwind</tt></a> instruction. </li>
+ <li>The optional <a href="#fnattrs">function attributes</a> list. Only
+ '<tt>noreturn</tt>', '<tt>nounwind</tt>', '<tt>readonly</tt>' and
+ '<tt>readnone</tt>' attributes are valid here.</li>
</ol>
<h5>Semantics:</h5>
<h5>Semantics:</h5>
-<p>The '<tt>unwind</tt>' intrinsic causes execution of the current function to
+<p>The '<tt>unwind</tt>' instruction causes execution of the current function to
immediately halt. The dynamic call stack is then searched for the first <a
href="#i_invoke"><tt>invoke</tt></a> instruction on the call stack. Once found,
execution continues at the "exceptional" destination block specified by the
<div class="doc_subsection"> <a name="binaryops">Binary Operations</a> </div>
<div class="doc_text">
<p>Binary operators are used to do most of the computation in a
-program. They require two operands, execute an operation on them, and
+program. They require two operands of the same type, 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_vector">vector</a> data type.
-The result value of a binary operator is not
-necessarily the same type as its operands.</p>
+The result value has the same type as its operands.</p>
<p>There are several different binary operators:</p>
</div>
<!-- _______________________________________________________________________ -->
-<div class="doc_subsubsection"> <a name="i_add">'<tt>add</tt>'
-Instruction</a> </div>
+<div class="doc_subsubsection">
+ <a name="i_add">'<tt>add</tt>' Instruction</a>
+</div>
+
<div class="doc_text">
+
<h5>Syntax:</h5>
-<pre> <result> = add <ty> <var1>, <var2> <i>; yields {ty}:result</i>
+
+<pre>
+ <result> = add <ty> <op1>, <op2> <i>; yields {ty}:result</i>
</pre>
+
<h5>Overview:</h5>
+
<p>The '<tt>add</tt>' instruction returns the sum of its two operands.</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_vector">vector</a> versions of the values.
-Both arguments must have identical types.</p>
+
+<p>The two arguments to the '<tt>add</tt>' instruction must be <a
+ href="#t_integer">integer</a>, <a href="#t_floating">floating point</a>, or
+ <a href="#t_vector">vector</a> 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
operands.</p>
+
<p>If an integer sum has unsigned overflow, the result returned is the
mathematical result modulo 2<sup>n</sup>, where n is the bit width of
the result.</p>
+
<p>Because LLVM integers use a two's complement representation, this
instruction is appropriate for both signed and unsigned integers.</p>
+
<h5>Example:</h5>
-<pre> <result> = add i32 4, %var <i>; yields {i32}:result = 4 + %var</i>
+
+<pre>
+ <result> = add i32 4, %var <i>; yields {i32}:result = 4 + %var</i>
</pre>
</div>
<!-- _______________________________________________________________________ -->
-<div class="doc_subsubsection"> <a name="i_sub">'<tt>sub</tt>'
-Instruction</a> </div>
+<div class="doc_subsubsection">
+ <a name="i_sub">'<tt>sub</tt>' Instruction</a>
+</div>
+
<div class="doc_text">
+
<h5>Syntax:</h5>
-<pre> <result> = sub <ty> <var1>, <var2> <i>; yields {ty}:result</i>
+
+<pre>
+ <result> = sub <ty> <op1>, <op2> <i>; yields {ty}:result</i>
</pre>
+
<h5>Overview:</h5>
+
<p>The '<tt>sub</tt>' instruction returns the difference of its two
operands.</p>
-<p>Note that the '<tt>sub</tt>' instruction is used to represent the '<tt>neg</tt>'
-instruction present in most other intermediate representations.</p>
+
+<p>Note that the '<tt>sub</tt>' instruction is used to represent the
+'<tt>neg</tt>' instruction present in most other intermediate
+representations.</p>
+
<h5>Arguments:</h5>
-<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_vector">vector</a> versions of the values.
-Both arguments must have identical types.</p>
+
+<p>The two arguments to the '<tt>sub</tt>' instruction must be <a
+ href="#t_integer">integer</a>, <a href="#t_floating">floating point</a>,
+ or <a href="#t_vector">vector</a> 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>
+
<p>If an integer difference has unsigned overflow, the result returned is the
mathematical result modulo 2<sup>n</sup>, where n is the bit width of
the result.</p>
+
<p>Because LLVM integers use a two's complement representation, this
instruction is appropriate for both signed and unsigned integers.</p>
+
<h5>Example:</h5>
<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>
+
<!-- _______________________________________________________________________ -->
-<div class="doc_subsubsection"> <a name="i_mul">'<tt>mul</tt>'
-Instruction</a> </div>
+<div class="doc_subsubsection">
+ <a name="i_mul">'<tt>mul</tt>' Instruction</a>
+</div>
+
<div class="doc_text">
+
<h5>Syntax:</h5>
-<pre> <result> = mul <ty> <var1>, <var2> <i>; yields {ty}:result</i>
+<pre> <result> = mul <ty> <op1>, <op2> <i>; yields {ty}:result</i>
</pre>
<h5>Overview:</h5>
<p>The '<tt>mul</tt>' instruction returns the product of its two
operands.</p>
+
<h5>Arguments:</h5>
-<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_vector">vector</a> versions of the values.
-Both arguments must have identical types.</p>
+
+<p>The two arguments to the '<tt>mul</tt>' instruction must be <a
+href="#t_integer">integer</a>, <a href="#t_floating">floating point</a>,
+or <a href="#t_vector">vector</a> values. Both arguments must have identical
+types.</p>
+
<h5>Semantics:</h5>
+
<p>The value produced is the integer or floating point product of the
two operands.</p>
+
<p>If the result of an integer multiplication has unsigned overflow,
the result returned is the mathematical result modulo
2<sup>n</sup>, where n is the bit width of the result.</p>
<pre> <result> = mul i32 4, %var <i>; yields {i32}:result = 4 * %var</i>
</pre>
</div>
+
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection"> <a name="i_udiv">'<tt>udiv</tt>' Instruction
</a></div>
<div class="doc_text">
<h5>Syntax:</h5>
-<pre> <result> = udiv <ty> <var1>, <var2> <i>; yields {ty}:result</i>
+<pre> <result> = udiv <ty> <op1>, <op2> <i>; yields {ty}:result</i>
</pre>
<h5>Overview:</h5>
<p>The '<tt>udiv</tt>' instruction returns the quotient of its two
operands.</p>
+
<h5>Arguments:</h5>
+
<p>The two arguments to the '<tt>udiv</tt>' instruction must be
-<a href="#t_integer">integer</a> values. Both arguments must have identical
-types. This instruction can also take <a href="#t_vector">vector</a> versions
-of the values in which case the elements must be integers.</p>
+<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
+values. Both arguments must have identical types.</p>
+
<h5>Semantics:</h5>
+
<p>The value produced is the unsigned integer quotient of the two operands.</p>
<p>Note that unsigned integer division and signed integer division are distinct
operations; for signed integer division, use '<tt>sdiv</tt>'.</p>
</a> </div>
<div class="doc_text">
<h5>Syntax:</h5>
-<pre> <result> = sdiv <ty> <var1>, <var2> <i>; yields {ty}:result</i>
+<pre>
+ <result> = sdiv <ty> <op1>, <op2> <i>; yields {ty}:result</i>
</pre>
+
<h5>Overview:</h5>
+
<p>The '<tt>sdiv</tt>' instruction returns the quotient of its two
operands.</p>
+
<h5>Arguments:</h5>
-<p>The two arguments to the '<tt>sdiv</tt>' instruction must be
-<a href="#t_integer">integer</a> values. Both arguments must have identical
-types. This instruction can also take <a href="#t_vector">vector</a> versions
-of the values in which case the elements must be integers.</p>
+
+<p>The two arguments to the '<tt>sdiv</tt>' instruction must be
+<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
+values. Both arguments must have identical types.</p>
+
<h5>Semantics:</h5>
-<p>The value produced is the signed integer quotient of the two operands.</p>
+<p>The value produced is the signed integer quotient of the two operands rounded towards zero.</p>
<p>Note that signed integer division and unsigned integer division are distinct
operations; for unsigned integer division, use '<tt>udiv</tt>'.</p>
<p>Division by zero leads to undefined behavior. Overflow also leads to
Instruction</a> </div>
<div class="doc_text">
<h5>Syntax:</h5>
-<pre> <result> = fdiv <ty> <var1>, <var2> <i>; yields {ty}:result</i>
+<pre>
+ <result> = fdiv <ty> <op1>, <op2> <i>; yields {ty}:result</i>
</pre>
<h5>Overview:</h5>
+
<p>The '<tt>fdiv</tt>' instruction returns the quotient of its two
operands.</p>
+
<h5>Arguments:</h5>
+
<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_vector">vector</a>
-versions of floating point values.</p>
+<a href="#t_floating">floating point</a> or <a href="#t_vector">vector</a>
+of floating point values. Both arguments must have identical types.</p>
+
<h5>Semantics:</h5>
+
<p>The value produced is the floating point quotient of the two operands.</p>
+
<h5>Example:</h5>
-<pre> <result> = fdiv float 4.0, %var <i>; yields {float}:result = 4.0 / %var</i>
+
+<pre>
+ <result> = fdiv float 4.0, %var <i>; yields {float}:result = 4.0 / %var</i>
</pre>
</div>
+
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection"> <a name="i_urem">'<tt>urem</tt>' Instruction</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
-<pre> <result> = urem <ty> <var1>, <var2> <i>; yields {ty}:result</i>
+<pre> <result> = urem <ty> <op1>, <op2> <i>; yields {ty}:result</i>
</pre>
<h5>Overview:</h5>
<p>The '<tt>urem</tt>' instruction returns the remainder from the
unsigned division of its two arguments.</p>
<h5>Arguments:</h5>
-<p>The two arguments to the '<tt>urem</tt>' instruction must be
-<a href="#t_integer">integer</a> values. Both arguments must have identical
-types. This instruction can also take <a href="#t_vector">vector</a> versions
-of the values in which case the elements must be integers.</p>
+<p>The two arguments to the '<tt>urem</tt>' instruction must be
+<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
+values. Both arguments must have identical types.</p>
<h5>Semantics:</h5>
<p>This instruction returns the unsigned integer <i>remainder</i> of a division.
-This instruction always performs an unsigned division to get the remainder,
-regardless of whether the arguments are unsigned or not.</p>
+This instruction always performs an unsigned division to get the remainder.</p>
<p>Note that unsigned integer remainder and signed integer remainder are
distinct operations; for signed integer remainder, use '<tt>srem</tt>'.</p>
<p>Taking the remainder of a division by zero leads to undefined behavior.</p>
</div>
<!-- _______________________________________________________________________ -->
-<div class="doc_subsubsection"> <a name="i_srem">'<tt>srem</tt>'
-Instruction</a> </div>
+<div class="doc_subsubsection">
+ <a name="i_srem">'<tt>srem</tt>' Instruction</a>
+</div>
+
<div class="doc_text">
+
<h5>Syntax:</h5>
-<pre> <result> = srem <ty> <var1>, <var2> <i>; yields {ty}:result</i>
+
+<pre>
+ <result> = srem <ty> <op1>, <op2> <i>; yields {ty}:result</i>
</pre>
+
<h5>Overview:</h5>
+
<p>The '<tt>srem</tt>' instruction returns the remainder from the
signed division of its two operands. 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>Arguments:</h5>
+
<p>The two arguments to the '<tt>srem</tt>' instruction must be
-<a href="#t_integer">integer</a> values. Both arguments must have identical
-types.</p>
+<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
+values. Both arguments must have identical 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 dividend, <tt>var1</tt>), not the <i>modulo</i>
-operator (where the result has the same sign as the divisor, <tt>var2</tt>) of
+has the same sign as the dividend, <tt>op1</tt>), not the <i>modulo</i>
+operator (where the result has the same sign as the divisor, <tt>op2</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>. For a table of how this is implemented in various languages,
</div>
<!-- _______________________________________________________________________ -->
-<div class="doc_subsubsection"> <a name="i_frem">'<tt>frem</tt>'
-Instruction</a> </div>
+<div class="doc_subsubsection">
+ <a name="i_frem">'<tt>frem</tt>' Instruction</a> </div>
+
<div class="doc_text">
+
<h5>Syntax:</h5>
-<pre> <result> = frem <ty> <var1>, <var2> <i>; yields {ty}:result</i>
+<pre> <result> = frem <ty> <op1>, <op2> <i>; yields {ty}:result</i>
</pre>
<h5>Overview:</h5>
<p>The '<tt>frem</tt>' instruction returns the remainder from the
division of its two operands.</p>
<h5>Arguments:</h5>
<p>The two arguments to the '<tt>frem</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_vector">vector</a>
-versions of floating point values.</p>
+<a href="#t_floating">floating point</a> or <a href="#t_vector">vector</a>
+of floating point values. Both arguments must have identical types.</p>
+
<h5>Semantics:</h5>
-<p>This instruction returns the <i>remainder</i> of a division.</p>
+
+<p>This instruction returns the <i>remainder</i> of a division.
+The remainder has the same sign as the dividend.</p>
+
<h5>Example:</h5>
-<pre> <result> = frem float 4.0, %var <i>; yields {float}:result = 4.0 % %var</i>
+
+<pre>
+ <result> = frem float 4.0, %var <i>; yields {float}:result = 4.0 % %var</i>
</pre>
</div>
<p>Bitwise binary operators are used to do various forms of
bit-twiddling in a program. They are generally very efficient
instructions and can commonly be strength reduced from other
-instructions. They require two operands, execute an operation on them,
-and produce a single value. The resulting value of the bitwise binary
-operators is always the same type as its first operand.</p>
+instructions. They require two operands of the same type, execute an operation on them,
+and produce a single value. The resulting value is the same type as its operands.</p>
</div>
<!-- _______________________________________________________________________ -->
Instruction</a> </div>
<div class="doc_text">
<h5>Syntax:</h5>
-<pre> <result> = shl <ty> <var1>, <var2> <i>; yields {ty}:result</i>
+<pre> <result> = shl <ty> <op1>, <op2> <i>; yields {ty}:result</i>
</pre>
<h5>Overview:</h5>
<h5>Arguments:</h5>
<p>Both arguments to the '<tt>shl</tt>' instruction must be the same <a
- href="#t_integer">integer</a> type.</p>
+ href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
+type. '<tt>op2</tt>' is treated as an unsigned value.</p>
<h5>Semantics:</h5>
-<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>
+<p>The value produced is <tt>op1</tt> * 2<sup><tt>op2</tt></sup> mod 2<sup>n</sup>,
+where n is the width of the result. If <tt>op2</tt> is (statically or dynamically) negative or
+equal to or larger than the number of bits in <tt>op1</tt>, the result is undefined.
+If the arguments are vectors, each vector element of <tt>op1</tt> is shifted by the
+corresponding shift amount in <tt>op2</tt>.</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>
+ <result> = shl <2 x i32> < i32 1, i32 1>, < i32 1, i32 2> <i>; yields: result=<2 x i32> < i32 2, i32 4></i>
</pre>
</div>
<!-- _______________________________________________________________________ -->
Instruction</a> </div>
<div class="doc_text">
<h5>Syntax:</h5>
-<pre> <result> = lshr <ty> <var1>, <var2> <i>; yields {ty}:result</i>
+<pre> <result> = lshr <ty> <op1>, <op2> <i>; yields {ty}:result</i>
</pre>
<h5>Overview:</h5>
<h5>Arguments:</h5>
<p>Both arguments to the '<tt>lshr</tt>' instruction must be the same
-<a href="#t_integer">integer</a> type.</p>
+<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
+type. '<tt>op2</tt>' is treated as an unsigned value.</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. 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>
+shift. If <tt>op2</tt> is (statically or dynamically) equal to or larger than
+the number of bits in <tt>op1</tt>, the result is undefined. If the arguments are
+vectors, each vector element of <tt>op1</tt> is shifted by the corresponding shift
+amount in <tt>op2</tt>.</p>
<h5>Example:</h5>
<pre>
<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>
+ <result> = lshr <2 x i32> < i32 -2, i32 4>, < i32 1, i32 2> <i>; yields: result=<2 x i32> < i32 0x7FFFFFFF, i32 1></i>
</pre>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
-<pre> <result> = ashr <ty> <var1>, <var2> <i>; yields {ty}:result</i>
+<pre> <result> = ashr <ty> <op1>, <op2> <i>; yields {ty}:result</i>
</pre>
<h5>Overview:</h5>
<h5>Arguments:</h5>
<p>Both arguments to the '<tt>ashr</tt>' instruction must be the same
-<a href="#t_integer">integer</a> type.</p>
+<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
+type. '<tt>op2</tt>' is treated as an unsigned value.</p>
<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>. 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>
+of <tt>op1</tt>. If <tt>op2</tt> is (statically or dynamically) equal to or
+larger than the number of bits in <tt>op1</tt>, the result is undefined. If the
+arguments are vectors, each vector element of <tt>op1</tt> is shifted by the
+corresponding shift amount in <tt>op2</tt>.</p>
<h5>Example:</h5>
<pre>
<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>
+ <result> = ashr <2 x i32> < i32 -2, i32 4>, < i32 1, i32 3> <i>; yields: result=<2 x i32> < i32 -1, i32 0></i>
</pre>
</div>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection"> <a name="i_and">'<tt>and</tt>'
Instruction</a> </div>
+
<div class="doc_text">
+
<h5>Syntax:</h5>
-<pre> <result> = and <ty> <var1>, <var2> <i>; yields {ty}:result</i>
+
+<pre>
+ <result> = and <ty> <op1>, <op2> <i>; yields {ty}:result</i>
</pre>
+
<h5>Overview:</h5>
+
<p>The '<tt>and</tt>' instruction returns the bitwise logical and of
its two operands.</p>
+
<h5>Arguments:</h5>
-<p>The two arguments to the '<tt>and</tt>' instruction must be <a
- href="#t_integer">integer</a> values. Both arguments must have
-identical types.</p>
+
+<p>The two arguments to the '<tt>and</tt>' instruction must be
+<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
+values. Both arguments must have identical types.</p>
+
<h5>Semantics:</h5>
<p>The truth table used for the '<tt>and</tt>' instruction is:</p>
<p> </p>
-<div style="align: center">
+<div>
<table border="1" cellspacing="0" cellpadding="4">
<tbody>
<tr>
</table>
</div>
<h5>Example:</h5>
-<pre> <result> = and i32 4, %var <i>; yields {i32}:result = 4 & %var</i>
+<pre>
+ <result> = and i32 4, %var <i>; yields {i32}:result = 4 & %var</i>
<result> = and i32 15, 40 <i>; yields {i32}:result = 8</i>
<result> = and i32 4, 8 <i>; yields {i32}:result = 0</i>
</pre>
<div class="doc_subsubsection"> <a name="i_or">'<tt>or</tt>' Instruction</a> </div>
<div class="doc_text">
<h5>Syntax:</h5>
-<pre> <result> = or <ty> <var1>, <var2> <i>; yields {ty}:result</i>
+<pre> <result> = or <ty> <op1>, <op2> <i>; yields {ty}:result</i>
</pre>
<h5>Overview:</h5>
<p>The '<tt>or</tt>' instruction returns the bitwise logical inclusive
or of its two operands.</p>
<h5>Arguments:</h5>
-<p>The two arguments to the '<tt>or</tt>' instruction must be <a
- href="#t_integer">integer</a> values. Both arguments must have
-identical types.</p>
+
+<p>The two arguments to the '<tt>or</tt>' instruction must be
+<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
+values. Both arguments must have identical types.</p>
<h5>Semantics:</h5>
<p>The truth table used for the '<tt>or</tt>' instruction is:</p>
<p> </p>
-<div style="align: center">
+<div>
<table border="1" cellspacing="0" cellpadding="4">
<tbody>
<tr>
Instruction</a> </div>
<div class="doc_text">
<h5>Syntax:</h5>
-<pre> <result> = xor <ty> <var1>, <var2> <i>; yields {ty}:result</i>
+<pre> <result> = xor <ty> <op1>, <op2> <i>; yields {ty}:result</i>
</pre>
<h5>Overview:</h5>
<p>The '<tt>xor</tt>' instruction returns the bitwise logical exclusive
or of its two operands. The <tt>xor</tt> is used to implement the
"one's complement" operation, which is the "~" operator in C.</p>
<h5>Arguments:</h5>
-<p>The two arguments to the '<tt>xor</tt>' instruction must be <a
- href="#t_integer">integer</a> values. Both arguments must have
-identical types.</p>
+<p>The two arguments to the '<tt>xor</tt>' instruction must be
+<a href="#t_integer">integer</a> or <a href="#t_vector">vector</a> of integer
+values. Both arguments must have identical types.</p>
+
<h5>Semantics:</h5>
+
<p>The truth table used for the '<tt>xor</tt>' instruction is:</p>
<p> </p>
-<div style="align: center">
+<div>
<table border="1" cellspacing="0" cellpadding="4">
<tbody>
<tr>
<h5>Syntax:</h5>
<pre>
- <result> = insertelement <n x <ty>> <val>, <ty> <elt>, i32 <idx> <i>; yields <n x <ty>></i>
+ <result> = insertelement <n x <ty>> <val>, <ty> <elt>, i32 <idx> <i>; yields <n x <ty>></i>
</pre>
<h5>Overview:</h5>
<h5>Syntax:</h5>
<pre>
- <result> = shufflevector <n x <ty>> <v1>, <n x <ty>> <v2>, <n x i32> <mask> <i>; yields <n x <ty>></i>
+ <result> = shufflevector <n x <ty>> <v1>, <n x <ty>> <v2>, <m x i32> <mask> <i>; yields <m x <ty>></i>
</pre>
<h5>Overview:</h5>
<p>
The '<tt>shufflevector</tt>' instruction constructs a permutation of elements
-from two input vectors, returning a vector of the same type.
+from two input vectors, returning a vector with the same element type as
+the input and length that is the same as the shuffle mask.
</p>
<h5>Arguments:</h5>
<p>
-The first two operands of a '<tt>shufflevector</tt>' instruction are vectors
-with types that match each other and types that match the result of the
-instruction. The third argument is a shuffle mask, which has the same number
-of elements as the other vector type, but whose element type is always 'i32'.
+The first two operands of a '<tt>shufflevector</tt>' instruction are vectors
+with types that match each other. The third argument is a shuffle mask whose
+element type is always 'i32'. The result of the instruction is a vector whose
+length is the same as the shuffle mask and whose element type is the same as
+the element type of the first two operands.
</p>
<p>
<p>
The elements of the two input vectors are numbered from left to right across
both of the vectors. The shuffle mask operand specifies, for each element of
-the result vector, which element of the two input registers the result element
+the result vector, which element of the two input vectors the result element
gets. The element selector may be undef (meaning "don't care") and the second
operand may be undef if performing a shuffle from only one vector.
</p>
<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.
+ %result = shufflevector <8 x i32> %v1, <8 x i32> undef,
+ <4 x i32> <i32 0, i32 1, i32 2, i32 3> <i>; yields <4 x i32></i>
+ %result = shufflevector <4 x i32> %v1, <4 x i32> %v2,
+ <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7 > <i>; yields <8 x i32></i>
</pre>
</div>
<!-- ======================================================================= -->
<div class="doc_subsection">
- <a name="memoryops">Memory Access and Addressing Operations</a>
+ <a name="aggregateops">Aggregate Operations</a>
</div>
<div class="doc_text">
-<p>A key design point of an SSA-based representation is how it
-represents memory. In LLVM, no memory locations are in SSA form, which
-makes things very simple. This section describes how to read, write,
-allocate, and free memory in LLVM.</p>
+<p>LLVM supports several instructions for working with aggregate values.
+</p>
</div>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="i_malloc">'<tt>malloc</tt>' Instruction</a>
+ <a name="i_extractvalue">'<tt>extractvalue</tt>' Instruction</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- <result> = malloc <type>[, i32 <NumElements>][, align <alignment>] <i>; yields {type*}:result</i>
+ <result> = extractvalue <aggregate type> <val>, <idx>{, <idx>}*
</pre>
<h5>Overview:</h5>
-<p>The '<tt>malloc</tt>' instruction allocates memory from the system
-heap and returns a pointer to it. The object is always allocated in the generic
-address space (address space zero).</p>
+<p>
+The '<tt>extractvalue</tt>' instruction extracts the value of a struct field
+or array element from an aggregate value.
+</p>
-<h5>Arguments:</h5>
-<p>The '<tt>malloc</tt>' instruction allocates
-<tt>sizeof(<type>)*NumElements</tt>
-bytes of memory from the operating system and returns a pointer of the
-appropriate type to the program. If "NumElements" is specified, it is the
-number of elements allocated, otherwise "NumElements" is defaulted to be one.
-If an alignment is specified, the value result of the allocation is guaranteed to
-be aligned to at least that boundary. If not specified, or if zero, the target can
-choose to align the allocation on any convenient boundary.</p>
+<h5>Arguments:</h5>
-<p>'<tt>type</tt>' must be a sized type.</p>
+<p>
+The first operand of an '<tt>extractvalue</tt>' instruction is a
+value of <a href="#t_struct">struct</a> or <a href="#t_array">array</a>
+type. The operands are constant indices to specify which value to extract
+in a similar manner as indices in a
+'<tt><a href="#i_getelementptr">getelementptr</a></tt>' instruction.
+</p>
<h5>Semantics:</h5>
-<p>Memory is allocated using the system "<tt>malloc</tt>" function, and
-a pointer is returned.</p>
+<p>
+The result is the value at the position in the aggregate specified by
+the index operands.
+</p>
+
+<h5>Example:</h5>
+
+<pre>
+ %result = extractvalue {i32, float} %agg, 0 <i>; yields i32</i>
+</pre>
+</div>
+
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="i_insertvalue">'<tt>insertvalue</tt>' Instruction</a>
+</div>
+
+<div class="doc_text">
+
+<h5>Syntax:</h5>
+
+<pre>
+ <result> = insertvalue <aggregate type> <val>, <ty> <val>, <idx> <i>; yields <n x <ty>></i>
+</pre>
+
+<h5>Overview:</h5>
+
+<p>
+The '<tt>insertvalue</tt>' instruction inserts a value
+into a struct field or array element in an aggregate.
+</p>
+
+
+<h5>Arguments:</h5>
+
+<p>
+The first operand of an '<tt>insertvalue</tt>' instruction is a
+value of <a href="#t_struct">struct</a> or <a href="#t_array">array</a> type.
+The second operand is a first-class value to insert.
+The following operands are constant indices
+indicating the position at which to insert the value in a similar manner as
+indices in a
+'<tt><a href="#i_getelementptr">getelementptr</a></tt>' instruction.
+The value to insert must have the same type as the value identified
+by the indices.
+</p>
+
+<h5>Semantics:</h5>
+
+<p>
+The result is an aggregate of the same type as <tt>val</tt>. Its
+value is that of <tt>val</tt> except that the value at the position
+specified by the indices is that of <tt>elt</tt>.
+</p>
+
+<h5>Example:</h5>
+
+<pre>
+ %result = insertvalue {i32, float} %agg, i32 1, 0 <i>; yields {i32, float}</i>
+</pre>
+</div>
+
+
+<!-- ======================================================================= -->
+<div class="doc_subsection">
+ <a name="memoryops">Memory Access and Addressing Operations</a>
+</div>
+
+<div class="doc_text">
+
+<p>A key design point of an SSA-based representation is how it
+represents memory. In LLVM, no memory locations are in SSA form, which
+makes things very simple. This section describes how to read, write,
+allocate, and free memory in LLVM.</p>
+
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="i_malloc">'<tt>malloc</tt>' Instruction</a>
+</div>
+
+<div class="doc_text">
+
+<h5>Syntax:</h5>
+
+<pre>
+ <result> = malloc <type>[, i32 <NumElements>][, align <alignment>] <i>; yields {type*}:result</i>
+</pre>
+
+<h5>Overview:</h5>
+
+<p>The '<tt>malloc</tt>' instruction allocates memory from the system
+heap and returns a pointer to it. The object is always allocated in the generic
+address space (address space zero).</p>
+
+<h5>Arguments:</h5>
+
+<p>The '<tt>malloc</tt>' instruction allocates
+<tt>sizeof(<type>)*NumElements</tt>
+bytes of memory from the operating system and returns a pointer of the
+appropriate type to the program. If "NumElements" is specified, it is the
+number of elements allocated, otherwise "NumElements" is defaulted to be one.
+If a constant alignment is specified, the value result of the allocation is guaranteed to
+be aligned to at least that boundary. If not specified, or if zero, the target can
+choose to align the allocation on any convenient boundary.</p>
+
+<p>'<tt>type</tt>' must be a sized type.</p>
+
+<h5>Semantics:</h5>
+
+<p>Memory is allocated using the system "<tt>malloc</tt>" function, and
+a pointer is returned. The result of a zero byte allocation is undefined. The
+result is null if there is insufficient memory available.</p>
<h5>Example:</h5>
<pre>
- %array = malloc [4 x i8 ] <i>; yields {[%4 x i8]*}:array</i>
+ %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>
%array3 = malloc i32, i32 4, align 1024 <i>; yields {i32*}:array3</i>
%array4 = malloc i32, align 1024 <i>; yields {i32*}:array4</i>
</pre>
+
+<p>Note that the code generator does not yet respect the
+ alignment value.</p>
+
</div>
<!-- _______________________________________________________________________ -->
<h5>Syntax:</h5>
<pre>
- free <type> <value> <i>; yields {void}</i>
+ free <type> <value> <i>; yields {void}</i>
</pre>
<h5>Overview:</h5>
<h5>Semantics:</h5>
<p>Access to the memory pointed to by the pointer is no longer defined
-after this instruction executes.</p>
+after this instruction executes. If the pointer is null, the operation
+is a noop.</p>
<h5>Example:</h5>
<pre>
- %array = <a href="#i_malloc">malloc</a> [4 x i8] <i>; yields {[4 x i8]*}:array</i>
+ %array = <a href="#i_malloc">malloc</a> [4 x i8] <i>; yields {[4 x i8]*}:array</i>
free [4 x i8]* %array
</pre>
</div>
bytes of memory on the runtime stack, returning a pointer of the
appropriate type to the program. If "NumElements" is specified, it is the
number of elements allocated, otherwise "NumElements" is defaulted to be one.
-If an alignment is specified, the value result of the allocation is guaranteed
+If a constant alignment is specified, the value result of the allocation is guaranteed
to be aligned to at least that boundary. If not specified, or if zero, the target
can choose to align the allocation on any convenient boundary.</p>
<h5>Semantics:</h5>
-<p>Memory is allocated; a pointer is returned. '<tt>alloca</tt>'d
+<p>Memory is allocated; a pointer is returned. The operation is undefiend if
+there is insufficient stack space for the allocation. '<tt>alloca</tt>'d
memory is automatically released when the function returns. The '<tt>alloca</tt>'
instruction is commonly used to represent automatic variables that must
have an address available. When the function returns (either with the <tt><a
href="#i_ret">ret</a></tt> or <tt><a href="#i_unwind">unwind</a></tt>
-instructions), the memory is reclaimed.</p>
+instructions), the memory is reclaimed. Allocating zero bytes
+is legal, but the result is undefined.</p>
<h5>Example:</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, align 1024 <i>; yields {i32*}:ptr</i>
+ %ptr = alloca i32 <i>; yields {i32*}:ptr</i>
+ %ptr = alloca i32, i32 4 <i>; yields {i32*}:ptr</i>
+ %ptr = alloca i32, i32 4, align 1024 <i>; yields {i32*}:ptr</i>
+ %ptr = alloca i32, align 1024 <i>; yields {i32*}:ptr</i>
</pre>
</div>
volatile <tt>load</tt> and <tt><a href="#i_store">store</a></tt>
instructions. </p>
<p>
-The optional "align" argument specifies the alignment of the operation
+The optional constant "align" argument specifies the alignment of the operation
(that is, the alignment of the memory address). A value of 0 or an
omitted "align" argument means that the operation has the preferential
alignment for the target. It is the responsibility of the code emitter
<h5>Arguments:</h5>
<p>There are two arguments to the '<tt>store</tt>' instruction: a value
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 must be a pointer to the <a href="#t_firstclass">first class</a> 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
this <tt>store</tt> with other volatile <tt>load</tt> and <tt><a
href="#i_store">store</a></tt> instructions.</p>
<p>
-The optional "align" argument specifies the alignment of the operation
+The optional constant "align" argument specifies the alignment of the operation
(that is, the alignment of the memory address). A value of 0 or an
omitted "align" argument means that the operation has the preferential
alignment for the target. It is the responsibility of the code emitter
<div class="doc_text">
<h5>Syntax:</h5>
<pre>
- <result> = getelementptr <ty>* <ptrval>{, <ty> <idx>}*
+ <result> = getelementptr <pty>* <ptrval>{, <ty> <idx>}*
</pre>
<h5>Overview:</h5>
<p>
The '<tt>getelementptr</tt>' instruction is used to get the address of a
-subelement of an aggregate data structure.</p>
+subelement of an aggregate data structure. It performs address calculation only
+and does not access memory.</p>
<h5>Arguments:</h5>
-<p>This instruction takes a list of integer operands that indicate what
-elements of the aggregate object to index to. The actual types of the arguments
-provided depend on the type of the first pointer argument. The
-'<tt>getelementptr</tt>' instruction is used to index down through the type
-levels of a structure or to a specific index in an array. When indexing into a
-structure, only <tt>i32</tt> integer constants are allowed. When indexing
-into an array or pointer, only integers of 32 or 64 bits are allowed, and will
-be sign extended to 64-bit values.</p>
+<p>The first argument is always a pointer, and forms the basis of the
+calculation. The remaining arguments are indices, that indicate which of the
+elements of the aggregate object are indexed. The interpretation of each index
+is dependent on the type being indexed into. The first index always indexes the
+pointer value given as the first argument, the second index indexes a value of
+the type pointed to (not necessarily the value directly pointed to, since the
+first index can be non-zero), etc. The first type indexed into must be a pointer
+value, subsequent types can be arrays, vectors and structs. Note that subsequent
+types being indexed into can never be pointers, since that would require loading
+the pointer before continuing calculation.</p>
+
+<p>The type of each index argument depends on the type it is indexing into.
+When indexing into a (packed) structure, only <tt>i32</tt> integer
+<b>constants</b> are allowed. When indexing into an array, pointer or vector,
+only integers of 32 or 64 bits are allowed (also non-constants). 32-bit values
+will be sign extended to 64-bits if required.</p>
<p>For example, let's consider a C code fragment and how it gets
compiled to LLVM:</p>
<div class="doc_code">
<pre>
-%RT = type { i8 , [10 x [20 x i32]], i8 }
-%ST = type { i32, double, %RT }
+%RT = <a href="#namedtypes">type</a> { i8 , [10 x [20 x i32]], i8 }
+%ST = <a href="#namedtypes">type</a> { i32, double, %RT }
define i32* %foo(%ST* %s) {
entry:
<h5>Semantics:</h5>
-<p>The index types specified for the '<tt>getelementptr</tt>' instruction depend
-on the pointer type that is being indexed into. <a href="#t_pointer">Pointer</a>
-and <a href="#t_array">array</a> types can use a 32-bit or 64-bit
-<a href="#t_integer">integer</a> type but the value will always be sign extended
-to 64-bits. <a href="#t_struct">Structure</a> types require <tt>i32</tt>
-<b>constants</b>.</p>
-
<p>In the example above, the first index is indexing into the '<tt>%ST*</tt>'
type, which is a pointer, yielding a '<tt>%ST</tt>' = '<tt>{ i32, double, %RT
}</tt>' type, a structure. The second index indexes into the third element of
<p>Note that it is undefined to access an array out of bounds: array and
pointer indexes must always be within the defined bounds of the array type.
-The one exception for this rules is zero length arrays. These arrays are
+The one exception for this rule is zero length arrays. These arrays are
defined to be accessible as variable length arrays, which requires access
beyond the zero'th element.</p>
<pre>
<i>; yields [12 x i8]*:aptr</i>
- %aptr = getelementptr {i32, [12 x i8]}* %sptr, i64 0, i32 1
+ %aptr = getelementptr {i32, [12 x i8]}* %saptr, i64 0, i32 1
+ <i>; yields i8*:vptr</i>
+ %vptr = getelementptr {i32, <2 x i8>}* %svptr, i64 0, i32 1, i32 1
+ <i>; yields i8*:eptr</i>
+ %eptr = getelementptr [12 x i8]* %aptr, i64 0, i32 1
</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
-<tt>ty2</tt>, which must be an <a href="#t_integer">integer</a> type.
+<tt>ty2</tt>, which must be an <a href="#t_integer">integer</a> type.</p>
<h5>Semantics:</h5>
<p>The '<tt>ptrtoint</tt>' instruction converts <tt>value</tt> to integer type
<h5>Arguments:</h5>
<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.
+<a href="#t_pointer">pointer</a> type.</p>
<h5>Semantics:</h5>
<p>The '<tt>inttoptr</tt>' instruction converts <tt>value</tt> to type
</pre>
<h5>Overview:</h5>
+
<p>The '<tt>bitcast</tt>' instruction converts <tt>value</tt> to type
<tt>ty2</tt> without changing any bits.</p>
<h5>Arguments:</h5>
+
<p>The '<tt>bitcast</tt>' instruction takes a value to cast, which must be
-a first class value, and a type to cast it to, which must also be a <a
- href="#t_firstclass">first class</a> type. The bit sizes of <tt>value</tt>
+a non-aggregate first class value, and a type to cast it to, which must also be
+a non-aggregate <a href="#t_firstclass">first class</a> type. The bit sizes of
+<tt>value</tt>
and the destination type, <tt>ty2</tt>, must be identical. If the source
-type is a pointer, the destination type must also be a pointer.</p>
+type is a pointer, the destination type must also be a pointer. This
+instruction supports bitwise conversion of vectors to integers and to vectors
+of other types (as long as they have the same size).</p>
<h5>Semantics:</h5>
<p>The '<tt>bitcast</tt>' instruction converts <tt>value</tt> to type
<pre>
%X = bitcast i8 255 to i8 <i>; yields i8 :-1</i>
%Y = bitcast i32* %x to sint* <i>; yields sint*:%x</i>
- %Z = bitcast <2xint> %V to i64; <i>; yields i64: %V</i>
+ %Z = bitcast <2 x int> %V to i64; <i>; yields i64: %V</i>
</pre>
</div>
</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> <op1>, <op2> <i>; yields {i1} or {<N x 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>
+<p>The '<tt>icmp</tt>' instruction returns a boolean value or
+a vector of boolean values based on comparison
+of its two integer, integer vector, or pointer operands.</p>
<h5>Arguments:</h5>
<p>The '<tt>icmp</tt>' instruction takes three operands. The first operand is
the condition code indicating the kind of comparison to perform. It is not
a value, just a keyword. The possible condition code are:
+</p>
<ol>
<li><tt>eq</tt>: equal</li>
<li><tt>ne</tt>: not equal </li>
<li><tt>sle</tt>: signed less or equal</li>
</ol>
<p>The remaining two arguments must be <a href="#t_integer">integer</a> or
-<a href="#t_pointer">pointer</a> typed. They must also be identical types.</p>
+<a href="#t_pointer">pointer</a>
+or integer <a href="#t_vector">vector</a> typed.
+They must also be identical types.</p>
<h5>Semantics:</h5>
-<p>The '<tt>icmp</tt>' compares <tt>var1</tt> and <tt>var2</tt> according to
+<p>The '<tt>icmp</tt>' compares <tt>op1</tt> and <tt>op2</tt> according to
the condition code given as <tt>cond</tt>. The comparison performed always
-yields a <a href="#t_primitive">i1</a> result, as follows:
+yields either an <a href="#t_primitive"><tt>i1</tt></a> or vector of <tt>i1</tt> result, as follows:
+</p>
<ol>
<li><tt>eq</tt>: yields <tt>true</tt> if the operands are equal,
<tt>false</tt> otherwise. No sign interpretation is necessary or performed.
</li>
<li><tt>ne</tt>: yields <tt>true</tt> if the operands are unequal,
- <tt>false</tt> otherwise. No sign interpretation is necessary or performed.
+ <tt>false</tt> otherwise. No sign interpretation is necessary or performed.</li>
<li><tt>ugt</tt>: interprets the operands as unsigned values and yields
- <tt>true</tt> if <tt>var1</tt> is greater than <tt>var2</tt>.</li>
+ <tt>true</tt> if <tt>op1</tt> is greater than <tt>op2</tt>.</li>
<li><tt>uge</tt>: interprets the operands as unsigned values and yields
- <tt>true</tt> if <tt>var1</tt> is greater than or equal to <tt>var2</tt>.</li>
+ <tt>true</tt> if <tt>op1</tt> is greater than or equal to <tt>op2</tt>.</li>
<li><tt>ult</tt>: interprets the operands as unsigned values and yields
- <tt>true</tt> if <tt>var1</tt> is less than <tt>var2</tt>.</li>
+ <tt>true</tt> if <tt>op1</tt> is less than <tt>op2</tt>.</li>
<li><tt>ule</tt>: interprets the operands as unsigned values and yields
- <tt>true</tt> if <tt>var1</tt> is less than or equal to <tt>var2</tt>.</li>
+ <tt>true</tt> if <tt>op1</tt> is less than or equal to <tt>op2</tt>.</li>
<li><tt>sgt</tt>: interprets the operands as signed values and yields
- <tt>true</tt> if <tt>var1</tt> is greater than <tt>var2</tt>.</li>
+ <tt>true</tt> if <tt>op1</tt> is greater than <tt>op2</tt>.</li>
<li><tt>sge</tt>: interprets the operands as signed values and yields
- <tt>true</tt> if <tt>var1</tt> is greater than or equal to <tt>var2</tt>.</li>
+ <tt>true</tt> if <tt>op1</tt> is greater than or equal to <tt>op2</tt>.</li>
<li><tt>slt</tt>: interprets the operands as signed values and yields
- <tt>true</tt> if <tt>var1</tt> is less than <tt>var2</tt>.</li>
+ <tt>true</tt> if <tt>op1</tt> is less than <tt>op2</tt>.</li>
<li><tt>sle</tt>: interprets the operands as signed values and yields
- <tt>true</tt> if <tt>var1</tt> is less than or equal to <tt>var2</tt>.</li>
+ <tt>true</tt> if <tt>op1</tt> is less than or equal to <tt>op2</tt>.</li>
</ol>
<p>If the operands are <a href="#t_pointer">pointer</a> typed, the pointer
values are compared as if they were integers.</p>
+<p>If the operands are integer vectors, then they are compared
+element by element. The result is an <tt>i1</tt> vector with
+the same number of elements as the values being compared.
+Otherwise, the result is an <tt>i1</tt>.
+</p>
<h5>Example:</h5>
<pre> <result> = icmp eq i32 4, 5 <i>; yields: result=false</i>
<result> = icmp ule i16 -4, 5 <i>; yields: result=false</i>
<result> = icmp sge i16 4, 5 <i>; yields: result=false</i>
</pre>
+
+<p>Note that the code generator does not yet support vector types with
+ the <tt>icmp</tt> instruction.</p>
+
</div>
<!-- _______________________________________________________________________ -->
</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> <op1>, <op2> <i>; yields {i1} or {<N x 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>
+<p>The '<tt>fcmp</tt>' instruction returns a boolean value
+or vector of boolean values based on comparison
+of its operands.</p>
+<p>
+If the operands are floating point scalars, then the result
+type is a boolean (<a href="#t_primitive"><tt>i1</tt></a>).
+</p>
+<p>If the operands are floating point vectors, then the result type
+is a vector of boolean with the same number of elements as the
+operands being compared.</p>
<h5>Arguments:</h5>
<p>The '<tt>fcmp</tt>' instruction takes three operands. The first operand is
the condition code indicating the kind of comparison to perform. It is not
-a value, just a keyword. The possible condition code are:
+a value, just a keyword. The possible condition code are:</p>
<ol>
<li><tt>false</tt>: no comparison, always returns false</li>
<li><tt>oeq</tt>: ordered and equal</li>
</ol>
<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>Each of <tt>val1</tt> and <tt>val2</tt> arguments must be
+either a <a href="#t_floating">floating point</a> type
+or a <a href="#t_vector">vector</a> of floating point type.
+They must have identical types.</p>
<h5>Semantics:</h5>
-<p>The '<tt>fcmp</tt>' compares <tt>var1</tt> and <tt>var2</tt> according to
-the condition code given as <tt>cond</tt>. The comparison performed always
-yields a <a href="#t_primitive">i1</a> result, as follows:
+<p>The '<tt>fcmp</tt>' instruction compares <tt>op1</tt> and <tt>op2</tt>
+according to the condition code given as <tt>cond</tt>.
+If the operands are vectors, then the vectors are compared
+element by element.
+Each comparison performed
+always yields an <a href="#t_primitive">i1</a> result, as follows:</p>
<ol>
<li><tt>false</tt>: always yields <tt>false</tt>, regardless of operands.</li>
<li><tt>oeq</tt>: yields <tt>true</tt> if both operands are not a QNAN and
- <tt>var1</tt> is equal to <tt>var2</tt>.</li>
+ <tt>op1</tt> is equal to <tt>op2</tt>.</li>
<li><tt>ogt</tt>: yields <tt>true</tt> if both operands are not a QNAN and
- <tt>var1</tt> is greather than <tt>var2</tt>.</li>
+ <tt>op1</tt> is greather than <tt>op2</tt>.</li>
<li><tt>oge</tt>: yields <tt>true</tt> if both operands are not a QNAN and
- <tt>var1</tt> is greater than or equal to <tt>var2</tt>.</li>
+ <tt>op1</tt> is greater than or equal to <tt>op2</tt>.</li>
<li><tt>olt</tt>: yields <tt>true</tt> if both operands are not a QNAN and
- <tt>var1</tt> is less than <tt>var2</tt>.</li>
+ <tt>op1</tt> is less than <tt>op2</tt>.</li>
<li><tt>ole</tt>: yields <tt>true</tt> if both operands are not a QNAN and
- <tt>var1</tt> is less than or equal to <tt>var2</tt>.</li>
+ <tt>op1</tt> is less than or equal to <tt>op2</tt>.</li>
<li><tt>one</tt>: yields <tt>true</tt> if both operands are not a QNAN and
- <tt>var1</tt> is not equal to <tt>var2</tt>.</li>
+ <tt>op1</tt> is not equal to <tt>op2</tt>.</li>
<li><tt>ord</tt>: yields <tt>true</tt> if both operands are not a QNAN.</li>
<li><tt>ueq</tt>: yields <tt>true</tt> if either operand is a QNAN or
- <tt>var1</tt> is equal to <tt>var2</tt>.</li>
+ <tt>op1</tt> is equal to <tt>op2</tt>.</li>
<li><tt>ugt</tt>: yields <tt>true</tt> if either operand is a QNAN or
- <tt>var1</tt> is greater than <tt>var2</tt>.</li>
+ <tt>op1</tt> is greater than <tt>op2</tt>.</li>
<li><tt>uge</tt>: yields <tt>true</tt> if either operand is a QNAN or
- <tt>var1</tt> is greater than or equal to <tt>var2</tt>.</li>
+ <tt>op1</tt> is greater than or equal to <tt>op2</tt>.</li>
<li><tt>ult</tt>: yields <tt>true</tt> if either operand is a QNAN or
- <tt>var1</tt> is less than <tt>var2</tt>.</li>
+ <tt>op1</tt> is less than <tt>op2</tt>.</li>
<li><tt>ule</tt>: yields <tt>true</tt> if either operand is a QNAN or
- <tt>var1</tt> is less than or equal to <tt>var2</tt>.</li>
+ <tt>op1</tt> is less than or equal to <tt>op2</tt>.</li>
<li><tt>une</tt>: yields <tt>true</tt> if either operand is a QNAN or
- <tt>var1</tt> is not equal to <tt>var2</tt>.</li>
+ <tt>op1</tt> is not equal to <tt>op2</tt>.</li>
<li><tt>uno</tt>: yields <tt>true</tt> if either operand is a QNAN.</li>
<li><tt>true</tt>: always yields <tt>true</tt>, regardless of operands.</li>
</ol>
<h5>Example:</h5>
<pre> <result> = fcmp oeq float 4.0, 5.0 <i>; yields: result=false</i>
- <result> = icmp one float 4.0, 5.0 <i>; yields: result=true</i>
- <result> = icmp olt float 4.0, 5.0 <i>; yields: result=true</i>
- <result> = icmp ueq double 1.0, 2.0 <i>; yields: result=false</i>
+ <result> = fcmp one float 4.0, 5.0 <i>; yields: result=true</i>
+ <result> = fcmp olt float 4.0, 5.0 <i>; yields: result=true</i>
+ <result> = fcmp ueq double 1.0, 2.0 <i>; yields: result=false</i>
</pre>
+
+<p>Note that the code generator does not yet support vector types with
+ the <tt>fcmp</tt> instruction.</p>
+
</div>
<!-- _______________________________________________________________________ -->
-<div class="doc_subsubsection"> <a name="i_phi">'<tt>phi</tt>'
-Instruction</a> </div>
+<div class="doc_subsubsection">
+ <a name="i_vicmp">'<tt>vicmp</tt>' Instruction</a>
+</div>
<div class="doc_text">
<h5>Syntax:</h5>
+<pre> <result> = vicmp <cond> <ty> <op1>, <op2> <i>; yields {ty}:result</i>
+</pre>
+<h5>Overview:</h5>
+<p>The '<tt>vicmp</tt>' instruction returns an integer vector value based on
+element-wise comparison of its two integer vector operands.</p>
+<h5>Arguments:</h5>
+<p>The '<tt>vicmp</tt>' instruction takes three operands. The first operand is
+the condition code indicating the kind of comparison to perform. It is not
+a value, just a keyword. The possible condition code are:</p>
+<ol>
+ <li><tt>eq</tt>: equal</li>
+ <li><tt>ne</tt>: not equal </li>
+ <li><tt>ugt</tt>: unsigned greater than</li>
+ <li><tt>uge</tt>: unsigned greater or equal</li>
+ <li><tt>ult</tt>: unsigned less than</li>
+ <li><tt>ule</tt>: unsigned less or equal</li>
+ <li><tt>sgt</tt>: signed greater than</li>
+ <li><tt>sge</tt>: signed greater or equal</li>
+ <li><tt>slt</tt>: signed less than</li>
+ <li><tt>sle</tt>: signed less or equal</li>
+</ol>
+<p>The remaining two arguments must be <a href="#t_vector">vector</a> or
+<a href="#t_integer">integer</a> typed. They must also be identical types.</p>
+<h5>Semantics:</h5>
+<p>The '<tt>vicmp</tt>' instruction compares <tt>op1</tt> and <tt>op2</tt>
+according to the condition code given as <tt>cond</tt>. The comparison yields a
+<a href="#t_vector">vector</a> of <a href="#t_integer">integer</a> result, of
+identical type as the values being compared. The most significant bit in each
+element is 1 if the element-wise comparison evaluates to true, and is 0
+otherwise. All other bits of the result are undefined. The condition codes
+are evaluated identically to the <a href="#i_icmp">'<tt>icmp</tt>'
+instruction</a>.</p>
+
+<h5>Example:</h5>
+<pre>
+ <result> = vicmp eq <2 x i32> < i32 4, i32 0>, < i32 5, i32 0> <i>; yields: result=<2 x i32> < i32 0, i32 -1 ></i>
+ <result> = vicmp ult <2 x i8 > < i8 1, i8 2>, < i8 2, i8 2 > <i>; yields: result=<2 x i8> < i8 -1, i8 0 ></i>
+</pre>
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="i_vfcmp">'<tt>vfcmp</tt>' Instruction</a>
+</div>
+<div class="doc_text">
+<h5>Syntax:</h5>
+<pre> <result> = vfcmp <cond> <ty> <op1>, <op2></pre>
+<h5>Overview:</h5>
+<p>The '<tt>vfcmp</tt>' instruction returns an integer vector value based on
+element-wise comparison of its two floating point vector operands. The output
+elements have the same width as the input elements.</p>
+<h5>Arguments:</h5>
+<p>The '<tt>vfcmp</tt>' instruction takes three operands. The first operand is
+the condition code indicating the kind of comparison to perform. It is not
+a value, just a keyword. The possible condition code are:</p>
+<ol>
+ <li><tt>false</tt>: no comparison, always returns false</li>
+ <li><tt>oeq</tt>: ordered and equal</li>
+ <li><tt>ogt</tt>: ordered and greater than </li>
+ <li><tt>oge</tt>: ordered and greater than or equal</li>
+ <li><tt>olt</tt>: ordered and less than </li>
+ <li><tt>ole</tt>: ordered and less than or equal</li>
+ <li><tt>one</tt>: ordered and not equal</li>
+ <li><tt>ord</tt>: ordered (no nans)</li>
+ <li><tt>ueq</tt>: unordered or equal</li>
+ <li><tt>ugt</tt>: unordered or greater than </li>
+ <li><tt>uge</tt>: unordered or greater than or equal</li>
+ <li><tt>ult</tt>: unordered or less than </li>
+ <li><tt>ule</tt>: unordered or less than or equal</li>
+ <li><tt>une</tt>: unordered or not equal</li>
+ <li><tt>uno</tt>: unordered (either nans)</li>
+ <li><tt>true</tt>: no comparison, always returns true</li>
+</ol>
+<p>The remaining two arguments must be <a href="#t_vector">vector</a> of
+<a href="#t_floating">floating point</a> typed. They must also be identical
+types.</p>
+<h5>Semantics:</h5>
+<p>The '<tt>vfcmp</tt>' instruction compares <tt>op1</tt> and <tt>op2</tt>
+according to the condition code given as <tt>cond</tt>. The comparison yields a
+<a href="#t_vector">vector</a> of <a href="#t_integer">integer</a> result, with
+an identical number of elements as the values being compared, and each element
+having identical with to the width of the floating point elements. The most
+significant bit in each element is 1 if the element-wise comparison evaluates to
+true, and is 0 otherwise. All other bits of the result are undefined. The
+condition codes are evaluated identically to the
+<a href="#i_fcmp">'<tt>fcmp</tt>' instruction</a>.</p>
+
+<h5>Example:</h5>
+<pre>
+ <i>; yields: result=<2 x i32> < i32 0, i32 -1 ></i>
+ <result> = vfcmp oeq <2 x float> < float 4, float 0 >, < float 5, float 0 >
+
+ <i>; yields: result=<2 x i64> < i64 -1, i64 0 ></i>
+ <result> = vfcmp ult <2 x double> < double 1, double 2 >, < double 2, double 2>
+</pre>
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="i_phi">'<tt>phi</tt>' Instruction</a>
+</div>
+
+<div class="doc_text">
+
+<h5>Syntax:</h5>
+
<pre> <result> = phi <ty> [ <val0>, <label0>], ...<br></pre>
<h5>Overview:</h5>
<p>The '<tt>phi</tt>' instruction is used to implement the φ node in
the SSA graph representing the function.</p>
<h5>Arguments:</h5>
+
<p>The type of the incoming values 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>
type may be used as the value arguments to the PHI node. Only labels
may be used as the label arguments.</p>
+
<p>There must be no non-phi instructions between the start of a basic
block and the PHI instructions: i.e. PHI instructions must be first in
a basic block.</p>
+
<h5>Semantics:</h5>
+
<p>At runtime, the '<tt>phi</tt>' instruction logically takes on the value
specified by the 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>
+<pre>
+Loop: ; Infinite loop that counts from 0 on up...
+ %indvar = phi i32 [ 0, %LoopHeader ], [ %nextindvar, %Loop ]
+ %nextindvar = add i32 %indvar, 1
+ br label %Loop
+</pre>
</div>
<!-- _______________________________________________________________________ -->
<h5>Syntax:</h5>
<pre>
- <result> = select i1 <cond>, <ty> <val1>, <ty> <val2> <i>; yields ty</i>
+ <result> = select <i>selty</i> <cond>, <ty> <val1>, <ty> <val2> <i>; yields ty</i>
+
+ <i>selty</i> is either i1 or {<N x i1>}
</pre>
<h5>Overview:</h5>
<h5>Arguments:</h5>
<p>
-The '<tt>select</tt>' instruction requires a boolean value indicating the condition, and two values of the same <a href="#t_firstclass">first class</a> type.
+The '<tt>select</tt>' instruction requires an 'i1' value or
+a vector of 'i1' values indicating the
+condition, and two values of the same <a href="#t_firstclass">first class</a>
+type. If the val1/val2 are vectors and
+the condition is a scalar, then entire vectors are selected, not
+individual elements.
</p>
<h5>Semantics:</h5>
<p>
-If the boolean condition evaluates to true, the instruction returns the first
+If the condition is an i1 and it evaluates to 1, the instruction returns the first
value argument; otherwise, it returns the second value argument.
</p>
+<p>
+If the condition is a vector of i1, then the value arguments must
+be vectors of the same size, and the selection is done element
+by element.
+</p>
<h5>Example:</h5>
<pre>
%X = select i1 true, i8 17, i8 42 <i>; yields i8:17</i>
</pre>
+
+<p>Note that the code generator does not yet support conditions
+ with vector type.</p>
+
</div>
<h5>Syntax:</h5>
<pre>
- <result> = [tail] call [<a href="#callingconv">cconv</a>] <ty> [<fnty>*] <fnptrval>(<param list>)
+ <result> = [tail] call [<a href="#callingconv">cconv</a>] [<a href="#paramattrs">ret attrs</a>] <ty> [<fnty>*] <fnptrval>(<function args>) [<a href="#fnattrs">fn attrs</a>]
</pre>
<h5>Overview:</h5>
any allocas or varargs in the caller. If the "tail" marker is present, the
function call is eligible for tail call optimization. Note that calls may
be marked "tail" even if they do not occur before a <a
- href="#i_ret"><tt>ret</tt></a> instruction.
+ href="#i_ret"><tt>ret</tt></a> instruction.</p>
</li>
<li>
<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.
+ to using C calling conventions.</p>
</li>
+
+ <li>
+ <p>The optional <a href="#paramattrs">Parameter Attributes</a> list for
+ return values. Only '<tt>zeroext</tt>', '<tt>signext</tt>',
+ and '<tt>inreg</tt>' attributes are valid here.</p>
+ </li>
+
<li>
<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
indicates the function accepts a variable number of arguments, the extra
arguments can be specified.</p>
</li>
+ <li>
+ <p>The optional <a href="#fnattrs">function attributes</a> list. Only
+ '<tt>noreturn</tt>', '<tt>nounwind</tt>', '<tt>readonly</tt>' and
+ '<tt>readnone</tt>' attributes are valid here.</p>
+ </li>
</ol>
<h5>Semantics:</h5>
the specified values. Upon a '<tt><a href="#i_ret">ret</a></tt>'
instruction in the called function, control flow continues with the
instruction after the function call, and the return value of the
-function is bound to the result argument. If the callee returns multiple
-values then the return values of the function are only accessible through
-the '<tt><a href="#i_getresult">getresult</a></tt>' instruction.</p>
+function is bound to the result argument.</p>
<h5>Example:</h5>
call void %foo(i8 97 signext)
%struct.A = type { i32, i8 }
- %r = call %struct.A @foo() <i>; yields { 32, i8 }</i>
- %gr = getresult %struct.A %r, 0 <i>; yields i32</i>
- %gr1 = getresult %struct.A %r, 1 <i>; yields i8</i>
+ %r = call %struct.A @foo() <i>; yields { 32, i8 }</i>
+ %gr = extractvalue %struct.A %r, 0 <i>; yields i32</i>
+ %gr1 = extractvalue %struct.A %r, 1 <i>; yields i8</i>
+ %Z = call void @foo() noreturn <i>; indicates that %foo never returns normally</i>
+ %ZZ = call zeroext i32 @bar() <i>; Return value is %zero extended</i>
</pre>
</div>
<p>See the <a href="#int_varargs">variable argument processing</a> section.</p>
-</div>
-
-<!-- _______________________________________________________________________ -->
-<div class="doc_subsubsection">
- <a name="i_getresult">'<tt>getresult</tt>' Instruction</a>
-</div>
-
-<div class="doc_text">
-
-<h5>Syntax:</h5>
-<pre>
- <resultval> = getresult <type> <retval>, <index>
-</pre>
-
-<h5>Overview:</h5>
-
-<p> The '<tt>getresult</tt>' instruction is used to extract individual values
-from a '<tt><a href="#i_call">call</a></tt>'
-or '<tt><a href="#i_invoke">invoke</a></tt>' instruction that returns multiple
-results.</p>
-
-<h5>Arguments:</h5>
-
-<p>The '<tt>getresult</tt>' instruction takes a call or invoke value as its
-first argument. The value must have <a href="#t_struct">structure type</a>.
-The second argument is an unsigned index value which must be in range for
-the number of values returned by the call.</p>
-
-<h5>Semantics:</h5>
-
-<p>The '<tt>getresult</tt>' instruction extracts the element identified by
-'<tt>index</tt>' from the aggregate value.</p>
-
-<h5>Example:</h5>
-
-<pre>
- %struct.A = type { i32, i8 }
-
- %r = call %struct.A @foo()
- %gr = getresult %struct.A %r, 0 <i>; yields i32:%gr</i>
- %gr1 = getresult %struct.A %r, 1 <i>; yields i8:%gr1</i>
- add i32 %gr, 42
- add i8 %gr1, 41
-</pre>
+<p>Note that the code generator does not yet fully support va_arg
+ on many targets. Also, it does not currently support va_arg with
+ aggregate types on any target.</p>
</div>
<h5>Syntax:</h5>
<pre> declare void %llvm.va_start(i8* <arglist>)<br></pre>
<h5>Overview:</h5>
-<P>The '<tt>llvm.va_start</tt>' intrinsic initializes
+<p>The '<tt>llvm.va_start</tt>' intrinsic initializes
<tt>*<arglist></tt> for subsequent use by <tt><a
href="#i_va_arg">va_arg</a></tt>.</p>
<h5>Arguments:</h5>
-<P>The argument is a pointer to a <tt>va_list</tt> element to initialize.</p>
+<p>The argument is a pointer to a <tt>va_list</tt> element to initialize.</p>
<h5>Semantics:</h5>
-<P>The '<tt>llvm.va_start</tt>' intrinsic works just like the <tt>va_start</tt>
+<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 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.
<p>
LLVM support for <a href="GarbageCollection.html">Accurate Garbage
-Collection</a> requires the implementation and generation of these intrinsics.
+Collection</a> (GC) requires the implementation and generation of these
+intrinsics.
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="#int_gcread">read</a> and <a href="#int_gcwrite">write</a> barriers.
<h5>Semantics:</h5>
-<p>At runtime, a call to this intrinsics stores a null pointer into the "ptrloc"
+<p>At runtime, a call to this intrinsic stores a null pointer into the "ptrloc"
location. At compile-time, the code generator generates information to allow
the runtime to find the pointer at GC safe points. The '<tt>llvm.gcroot</tt>'
intrinsic may only be used in a function which <a href="#gc">specifies a GC
<p>
The '<tt>llvm.pcmarker</tt>' intrinsic is a method to export a Program Counter
-(PC) in a region of
-code to simulators and other tools. The method is target specific, but it is
-expected that the marker will use exported symbols to transmit the PC of the marker.
-The marker makes no guarantees that it will remain with any specific instruction
-after optimizations. It is possible that the presence of a marker will inhibit
+(PC) in a region of
+code to simulators and other tools. The method is target specific, but it is
+expected that the marker will use exported symbols to transmit the PC of the
+marker.
+The marker makes no guarantees that it will remain with any specific instruction
+after optimizations. It is possible that the presence of a marker will inhibit
optimizations. The intended use is to be inserted after optimizations to allow
correlations of simulation runs.
</p>
<div class="doc_text">
<h5>Syntax:</h5>
+<p>This is an overloaded intrinsic. You can use llvm.memcpy on any integer bit
+width. Not all targets support all bit widths however.</p>
<pre>
+ declare void @llvm.memcpy.i8(i8 * <dest>, i8 * <src>,
+ i8 <len>, i32 <align>)
+ declare void @llvm.memcpy.i16(i8 * <dest>, i8 * <src>,
+ i16 <len>, i32 <align>)
declare void @llvm.memcpy.i32(i8 * <dest>, i8 * <src>,
i32 <len>, i32 <align>)
declare void @llvm.memcpy.i64(i8 * <dest>, i8 * <src>,
<div class="doc_text">
<h5>Syntax:</h5>
+<p>This is an overloaded intrinsic. You can use llvm.memmove on any integer bit
+width. Not all targets support all bit widths however.</p>
<pre>
+ declare void @llvm.memmove.i8(i8 * <dest>, i8 * <src>,
+ i8 <len>, i32 <align>)
+ declare void @llvm.memmove.i16(i8 * <dest>, i8 * <src>,
+ i16 <len>, i32 <align>)
declare void @llvm.memmove.i32(i8 * <dest>, i8 * <src>,
i32 <len>, i32 <align>)
declare void @llvm.memmove.i64(i8 * <dest>, i8 * <src>,
<div class="doc_text">
<h5>Syntax:</h5>
+<p>This is an overloaded intrinsic. You can use llvm.memset on any integer bit
+width. Not all targets support all bit widths however.</p>
<pre>
+ declare void @llvm.memset.i8(i8 * <dest>, i8 <val>,
+ i8 <len>, i32 <align>)
+ declare void @llvm.memset.i16(i8 * <dest>, i8 <val>,
+ i16 <len>, i32 <align>)
declare void @llvm.memset.i32(i8 * <dest>, i8 <val>,
i32 <len>, i32 <align>)
declare void @llvm.memset.i64(i8 * <dest>, i8 <val>,
<h5>Syntax:</h5>
<p>This is an overloaded intrinsic. You can use <tt>llvm.sqrt</tt> on any
floating point or vector of floating point type. Not all targets support all
-types however.
+types however.</p>
<pre>
declare float @llvm.sqrt.f32(float %Val)
declare double @llvm.sqrt.f64(double %Val)
<h5>Syntax:</h5>
<p>This is an overloaded intrinsic. You can use <tt>llvm.powi</tt> on any
floating point or vector of floating point type. Not all targets support all
-types however.
+types however.</p>
<pre>
declare float @llvm.powi.f32(float %Val, i32 %power)
declare double @llvm.powi.f64(double %Val, i32 %power)
<h5>Syntax:</h5>
<p>This is an overloaded intrinsic. You can use <tt>llvm.sin</tt> on any
floating point or vector of floating point type. Not all targets support all
-types however.
+types however.</p>
<pre>
declare float @llvm.sin.f32(float %Val)
declare double @llvm.sin.f64(double %Val)
<h5>Syntax:</h5>
<p>This is an overloaded intrinsic. You can use <tt>llvm.cos</tt> on any
floating point or vector of floating point type. Not all targets support all
-types however.
+types however.</p>
<pre>
declare float @llvm.cos.f32(float %Val)
declare double @llvm.cos.f64(double %Val)
<h5>Syntax:</h5>
<p>This is an overloaded intrinsic. You can use <tt>llvm.pow</tt> on any
floating point or vector of floating point type. Not all targets support all
-types however.
+types however.</p>
<pre>
declare float @llvm.pow.f32(float %Val, float %Power)
declare double @llvm.pow.f64(double %Val, double %Power)
<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).
+type that is an even number of bytes (i.e. BitWidth % 16 == 0).</p>
<pre>
declare i16 @llvm.bswap.i16(i16 <id>)
declare i32 @llvm.bswap.i32(i32 <id>)
<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.
+width. Not all targets support all bit widths however.</p>
<pre>
declare i8 @llvm.ctpop.i8 (i8 <src>)
declare i16 @llvm.ctpop.i16(i16 <src>)
<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.
+integer bit width. Not all targets support all bit widths however.</p>
<pre>
declare i8 @llvm.ctlz.i8 (i8 <src>)
declare i16 @llvm.ctlz.i16(i16 <src>)
<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.
+integer bit width. Not all targets support all bit widths however.</p>
<pre>
declare i8 @llvm.cttz.i8 (i8 <src>)
declare i16 @llvm.cttz.i16(i16 <src>)
<h5>Syntax:</h5>
<p>This is an overloaded intrinsic. You can use <tt>llvm.part.select</tt>
-on any integer bit width.
+on any integer bit width.</p>
<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)
<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.
+ <li>The mask is ANDed with <tt>%val</tt> to produce the result.</li>
</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
<h5>Syntax:</h5>
<p>This is an overloaded intrinsic. You can use <tt>llvm.part.set</tt>
-on any integer bit width.
+on any integer bit width.</p>
<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)
<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.
+to the <tt>%hi</tt>th bit.</p>
<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.
+<tt>%hi</tt> bit in <tt>%val</tt> and etc. down to the <tt>%lo</tt>th bit.</p>
<h5>Examples:</h5>
<pre>
llvm.part.set(0xFFFF, 0, 4, 7) -> 0xFF0F
These intrinsic functions expand the "universal IR" of LLVM to represent
hardware constructs for atomic operations and memory synchronization. This
provides an interface to the hardware, not an interface to the programmer. It
- is aimed at a low enough level to allow any programming models or APIs which
+ is aimed at a low enough level to allow any programming models or APIs
+ (Application Programming Interfaces) which
need atomic behaviors to map cleanly onto it. It is also modeled primarily on
hardware behavior. Just as hardware provides a "universal IR" for source
languages, it also provides a starting point for developing a "universal"
<li><tt>ls</tt>: load-store barrier</li>
<li><tt>sl</tt>: store-load barrier</li>
<li><tt>ss</tt>: store-store barrier</li>
- <li><tt>device</tt>: barrier applies to device and uncached memory also.
+ <li><tt>device</tt>: barrier applies to device and uncached memory also.</li>
</ul>
<h5>Semantics:</h5>
<p>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="int_atomic_lcs">'<tt>llvm.atomic.lcs.*</tt>' Intrinsic</a>
+ <a name="int_atomic_cmp_swap">'<tt>llvm.atomic.cmp.swap.*</tt>' Intrinsic</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<p>
- This is an overloaded intrinsic. You can use <tt>llvm.atomic.lcs</tt> on any
- integer bit width. Not all targets support all bit widths however.</p>
+ This is an overloaded intrinsic. You can use <tt>llvm.atomic.cmp.swap</tt> on
+ any integer bit width and for different address spaces. Not all targets
+ support all bit widths however.</p>
<pre>
-declare i8 @llvm.atomic.lcs.i8( i8* <ptr>, i8 <cmp>, i8 <val> )
-declare i16 @llvm.atomic.lcs.i16( i16* <ptr>, i16 <cmp>, i16 <val> )
-declare i32 @llvm.atomic.lcs.i32( i32* <ptr>, i32 <cmp>, i32 <val> )
-declare i64 @llvm.atomic.lcs.i64( i64* <ptr>, i64 <cmp>, i64 <val> )
+declare i8 @llvm.atomic.cmp.swap.i8.p0i8( i8* <ptr>, i8 <cmp>, i8 <val> )
+declare i16 @llvm.atomic.cmp.swap.i16.p0i16( i16* <ptr>, i16 <cmp>, i16 <val> )
+declare i32 @llvm.atomic.cmp.swap.i32.p0i32( i32* <ptr>, i32 <cmp>, i32 <val> )
+declare i64 @llvm.atomic.cmp.swap.i64.p0i64( i64* <ptr>, i64 <cmp>, i64 <val> )
</pre>
<h5>Overview:</h5>
</p>
<h5>Arguments:</h5>
<p>
- The <tt>llvm.atomic.lcs</tt> intrinsic takes three arguments. The result as
+ The <tt>llvm.atomic.cmp.swap</tt> intrinsic takes three arguments. The result as
well as both <tt>cmp</tt> and <tt>val</tt> must be integer values with the
same bit width. The <tt>ptr</tt> argument must be a pointer to a value of
this integer type. While any bit width integer may be used, targets may only
store i32 4, %ptr
%val1 = add i32 4, 4
-%result1 = call i32 @llvm.atomic.lcs.i32( i32* %ptr, i32 4, %val1 )
+%result1 = call i32 @llvm.atomic.cmp.swap.i32.p0i32( i32* %ptr, i32 4, %val1 )
<i>; yields {i32}:result1 = 4</i>
%stored1 = icmp eq i32 %result1, 4 <i>; yields {i1}:stored1 = true</i>
%memval1 = load i32* %ptr <i>; yields {i32}:memval1 = 8</i>
%val2 = add i32 1, 1
-%result2 = call i32 @llvm.atomic.lcs.i32( i32* %ptr, i32 5, %val2 )
+%result2 = call i32 @llvm.atomic.cmp.swap.i32.p0i32( i32* %ptr, i32 5, %val2 )
<i>; yields {i32}:result2 = 8</i>
%stored2 = icmp eq i32 %result2, 5 <i>; yields {i1}:stored2 = false</i>
This is an overloaded intrinsic. You can use <tt>llvm.atomic.swap</tt> on any
integer bit width. Not all targets support all bit widths however.</p>
<pre>
-declare i8 @llvm.atomic.swap.i8( i8* <ptr>, i8 <val> )
-declare i16 @llvm.atomic.swap.i16( i16* <ptr>, i16 <val> )
-declare i32 @llvm.atomic.swap.i32( i32* <ptr>, i32 <val> )
-declare i64 @llvm.atomic.swap.i64( i64* <ptr>, i64 <val> )
+declare i8 @llvm.atomic.swap.i8.p0i8( i8* <ptr>, i8 <val> )
+declare i16 @llvm.atomic.swap.i16.p0i16( i16* <ptr>, i16 <val> )
+declare i32 @llvm.atomic.swap.i32.p0i32( i32* <ptr>, i32 <val> )
+declare i64 @llvm.atomic.swap.i64.p0i64( i64* <ptr>, i64 <val> )
</pre>
<h5>Overview:</h5>
<h5>Arguments:</h5>
<p>
- The <tt>llvm.atomic.ls</tt> intrinsic takes two arguments. Both the
+ The <tt>llvm.atomic.swap</tt> intrinsic takes two arguments. Both the
<tt>val</tt> argument and the result must be integers of the same bit width.
The first argument, <tt>ptr</tt>, must be a pointer to a value of this
integer type. The targets may only lower integer representations they
store i32 4, %ptr
%val1 = add i32 4, 4
-%result1 = call i32 @llvm.atomic.swap.i32( i32* %ptr, i32 %val1 )
+%result1 = call i32 @llvm.atomic.swap.i32.p0i32( i32* %ptr, i32 %val1 )
<i>; yields {i32}:result1 = 4</i>
%stored1 = icmp eq i32 %result1, 4 <i>; yields {i1}:stored1 = true</i>
%memval1 = load i32* %ptr <i>; yields {i32}:memval1 = 8</i>
%val2 = add i32 1, 1
-%result2 = call i32 @llvm.atomic.swap.i32( i32* %ptr, i32 %val2 )
+%result2 = call i32 @llvm.atomic.swap.i32.p0i32( i32* %ptr, i32 %val2 )
<i>; yields {i32}:result2 = 8</i>
%stored2 = icmp eq i32 %result2, 8 <i>; yields {i1}:stored2 = true</i>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
- <a name="int_atomic_las">'<tt>llvm.atomic.las.*</tt>' Intrinsic</a>
+ <a name="int_atomic_load_add">'<tt>llvm.atomic.load.add.*</tt>' Intrinsic</a>
</div>
<div class="doc_text">
<h5>Syntax:</h5>
<p>
- This is an overloaded intrinsic. You can use <tt>llvm.atomic.las</tt> on any
+ This is an overloaded intrinsic. You can use <tt>llvm.atomic.load.add</tt> on any
integer bit width. Not all targets support all bit widths however.</p>
<pre>
-declare i8 @llvm.atomic.las.i8.( i8* <ptr>, i8 <delta> )
-declare i16 @llvm.atomic.las.i16.( i16* <ptr>, i16 <delta> )
-declare i32 @llvm.atomic.las.i32.( i32* <ptr>, i32 <delta> )
-declare i64 @llvm.atomic.las.i64.( i64* <ptr>, i64 <delta> )
+declare i8 @llvm.atomic.load.add.i8..p0i8( i8* <ptr>, i8 <delta> )
+declare i16 @llvm.atomic.load.add.i16..p0i16( i16* <ptr>, i16 <delta> )
+declare i32 @llvm.atomic.load.add.i32..p0i32( i32* <ptr>, i32 <delta> )
+declare i64 @llvm.atomic.load.add.i64..p0i64( i64* <ptr>, i64 <delta> )
</pre>
<h5>Overview:</h5>
<pre>
%ptr = malloc i32
store i32 4, %ptr
-%result1 = call i32 @llvm.atomic.las.i32( i32* %ptr, i32 4 )
+%result1 = call i32 @llvm.atomic.load.add.i32.p0i32( i32* %ptr, i32 4 )
<i>; yields {i32}:result1 = 4</i>
-%result2 = call i32 @llvm.atomic.las.i32( i32* %ptr, i32 2 )
+%result2 = call i32 @llvm.atomic.load.add.i32.p0i32( i32* %ptr, i32 2 )
<i>; yields {i32}:result2 = 8</i>
-%result3 = call i32 @llvm.atomic.las.i32( i32* %ptr, i32 5 )
+%result3 = call i32 @llvm.atomic.load.add.i32.p0i32( i32* %ptr, i32 5 )
<i>; yields {i32}:result3 = 10</i>
-%memval = load i32* %ptr <i>; yields {i32}:memval1 = 15</i>
+%memval1 = load i32* %ptr <i>; yields {i32}:memval1 = 15</i>
</pre>
</div>
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="int_atomic_load_sub">'<tt>llvm.atomic.load.sub.*</tt>' Intrinsic</a>
+
+</div>
+<div class="doc_text">
+<h5>Syntax:</h5>
+<p>
+ This is an overloaded intrinsic. You can use <tt>llvm.atomic.load.sub</tt> on
+ any integer bit width and for different address spaces. Not all targets
+ support all bit widths however.</p>
+<pre>
+declare i8 @llvm.atomic.load.sub.i8.p0i32( i8* <ptr>, i8 <delta> )
+declare i16 @llvm.atomic.load.sub.i16.p0i32( i16* <ptr>, i16 <delta> )
+declare i32 @llvm.atomic.load.sub.i32.p0i32( i32* <ptr>, i32 <delta> )
+declare i64 @llvm.atomic.load.sub.i64.p0i32( i64* <ptr>, i64 <delta> )
+
+</pre>
+<h5>Overview:</h5>
+<p>
+ This intrinsic subtracts <tt>delta</tt> to the value stored in memory at
+ <tt>ptr</tt>. It yields the original value at <tt>ptr</tt>.
+</p>
+<h5>Arguments:</h5>
+<p>
+
+ The intrinsic takes two arguments, the first a pointer to an integer value
+ and the second an integer value. The result is also an integer value. These
+ integer types can have any bit width, but they must all have the same bit
+ width. The targets may only lower integer representations they support.
+</p>
+<h5>Semantics:</h5>
+<p>
+ This intrinsic does a series of operations atomically. It first loads the
+ value stored at <tt>ptr</tt>. It then subtracts <tt>delta</tt>, stores the
+ result to <tt>ptr</tt>. It yields the original value stored at <tt>ptr</tt>.
+</p>
+
+<h5>Examples:</h5>
+<pre>
+%ptr = malloc i32
+ store i32 8, %ptr
+%result1 = call i32 @llvm.atomic.load.sub.i32.p0i32( i32* %ptr, i32 4 )
+ <i>; yields {i32}:result1 = 8</i>
+%result2 = call i32 @llvm.atomic.load.sub.i32.p0i32( i32* %ptr, i32 2 )
+ <i>; yields {i32}:result2 = 4</i>
+%result3 = call i32 @llvm.atomic.load.sub.i32.p0i32( i32* %ptr, i32 5 )
+ <i>; yields {i32}:result3 = 2</i>
+%memval1 = load i32* %ptr <i>; yields {i32}:memval1 = -3</i>
+</pre>
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="int_atomic_load_and">'<tt>llvm.atomic.load.and.*</tt>' Intrinsic</a><br>
+ <a name="int_atomic_load_nand">'<tt>llvm.atomic.load.nand.*</tt>' Intrinsic</a><br>
+ <a name="int_atomic_load_or">'<tt>llvm.atomic.load.or.*</tt>' Intrinsic</a><br>
+ <a name="int_atomic_load_xor">'<tt>llvm.atomic.load.xor.*</tt>' Intrinsic</a><br>
+
+</div>
+<div class="doc_text">
+<h5>Syntax:</h5>
+<p>
+ These are overloaded intrinsics. You can use <tt>llvm.atomic.load_and</tt>,
+ <tt>llvm.atomic.load_nand</tt>, <tt>llvm.atomic.load_or</tt>, and
+ <tt>llvm.atomic.load_xor</tt> on any integer bit width and for different
+ address spaces. Not all targets support all bit widths however.</p>
+<pre>
+declare i8 @llvm.atomic.load.and.i8.p0i8( i8* <ptr>, i8 <delta> )
+declare i16 @llvm.atomic.load.and.i16.p0i16( i16* <ptr>, i16 <delta> )
+declare i32 @llvm.atomic.load.and.i32.p0i32( i32* <ptr>, i32 <delta> )
+declare i64 @llvm.atomic.load.and.i64.p0i64( i64* <ptr>, i64 <delta> )
+
+</pre>
+
+<pre>
+declare i8 @llvm.atomic.load.or.i8.p0i8( i8* <ptr>, i8 <delta> )
+declare i16 @llvm.atomic.load.or.i16.p0i16( i16* <ptr>, i16 <delta> )
+declare i32 @llvm.atomic.load.or.i32.p0i32( i32* <ptr>, i32 <delta> )
+declare i64 @llvm.atomic.load.or.i64.p0i64( i64* <ptr>, i64 <delta> )
+
+</pre>
+
+<pre>
+declare i8 @llvm.atomic.load.nand.i8.p0i32( i8* <ptr>, i8 <delta> )
+declare i16 @llvm.atomic.load.nand.i16.p0i32( i16* <ptr>, i16 <delta> )
+declare i32 @llvm.atomic.load.nand.i32.p0i32( i32* <ptr>, i32 <delta> )
+declare i64 @llvm.atomic.load.nand.i64.p0i32( i64* <ptr>, i64 <delta> )
+
+</pre>
+
+<pre>
+declare i8 @llvm.atomic.load.xor.i8.p0i32( i8* <ptr>, i8 <delta> )
+declare i16 @llvm.atomic.load.xor.i16.p0i32( i16* <ptr>, i16 <delta> )
+declare i32 @llvm.atomic.load.xor.i32.p0i32( i32* <ptr>, i32 <delta> )
+declare i64 @llvm.atomic.load.xor.i64.p0i32( i64* <ptr>, i64 <delta> )
+
+</pre>
+<h5>Overview:</h5>
+<p>
+ These intrinsics bitwise the operation (and, nand, or, xor) <tt>delta</tt> to
+ the value stored in memory at <tt>ptr</tt>. It yields the original value
+ at <tt>ptr</tt>.
+</p>
+<h5>Arguments:</h5>
+<p>
+
+ These intrinsics take two arguments, the first a pointer to an integer value
+ and the second an integer value. The result is also an integer value. These
+ integer types can have any bit width, but they must all have the same bit
+ width. The targets may only lower integer representations they support.
+</p>
+<h5>Semantics:</h5>
+<p>
+ These intrinsics does a series of operations atomically. They first load the
+ value stored at <tt>ptr</tt>. They then do the bitwise operation
+ <tt>delta</tt>, store the result to <tt>ptr</tt>. They yield the original
+ value stored at <tt>ptr</tt>.
+</p>
+
+<h5>Examples:</h5>
+<pre>
+%ptr = malloc i32
+ store i32 0x0F0F, %ptr
+%result0 = call i32 @llvm.atomic.load.nand.i32.p0i32( i32* %ptr, i32 0xFF )
+ <i>; yields {i32}:result0 = 0x0F0F</i>
+%result1 = call i32 @llvm.atomic.load.and.i32.p0i32( i32* %ptr, i32 0xFF )
+ <i>; yields {i32}:result1 = 0xFFFFFFF0</i>
+%result2 = call i32 @llvm.atomic.load.or.i32.p0i32( i32* %ptr, i32 0F )
+ <i>; yields {i32}:result2 = 0xF0</i>
+%result3 = call i32 @llvm.atomic.load.xor.i32.p0i32( i32* %ptr, i32 0F )
+ <i>; yields {i32}:result3 = FF</i>
+%memval1 = load i32* %ptr <i>; yields {i32}:memval1 = F0</i>
+</pre>
+</div>
+
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="int_atomic_load_max">'<tt>llvm.atomic.load.max.*</tt>' Intrinsic</a><br>
+ <a name="int_atomic_load_min">'<tt>llvm.atomic.load.min.*</tt>' Intrinsic</a><br>
+ <a name="int_atomic_load_umax">'<tt>llvm.atomic.load.umax.*</tt>' Intrinsic</a><br>
+ <a name="int_atomic_load_umin">'<tt>llvm.atomic.load.umin.*</tt>' Intrinsic</a><br>
+
+</div>
+<div class="doc_text">
+<h5>Syntax:</h5>
+<p>
+ These are overloaded intrinsics. You can use <tt>llvm.atomic.load_max</tt>,
+ <tt>llvm.atomic.load_min</tt>, <tt>llvm.atomic.load_umax</tt>, and
+ <tt>llvm.atomic.load_umin</tt> on any integer bit width and for different
+ address spaces. Not all targets
+ support all bit widths however.</p>
+<pre>
+declare i8 @llvm.atomic.load.max.i8.p0i8( i8* <ptr>, i8 <delta> )
+declare i16 @llvm.atomic.load.max.i16.p0i16( i16* <ptr>, i16 <delta> )
+declare i32 @llvm.atomic.load.max.i32.p0i32( i32* <ptr>, i32 <delta> )
+declare i64 @llvm.atomic.load.max.i64.p0i64( i64* <ptr>, i64 <delta> )
+
+</pre>
+
+<pre>
+declare i8 @llvm.atomic.load.min.i8.p0i8( i8* <ptr>, i8 <delta> )
+declare i16 @llvm.atomic.load.min.i16.p0i16( i16* <ptr>, i16 <delta> )
+declare i32 @llvm.atomic.load.min.i32..p0i32( i32* <ptr>, i32 <delta> )
+declare i64 @llvm.atomic.load.min.i64..p0i64( i64* <ptr>, i64 <delta> )
+
+</pre>
+
+<pre>
+declare i8 @llvm.atomic.load.umax.i8.p0i8( i8* <ptr>, i8 <delta> )
+declare i16 @llvm.atomic.load.umax.i16.p0i16( i16* <ptr>, i16 <delta> )
+declare i32 @llvm.atomic.load.umax.i32.p0i32( i32* <ptr>, i32 <delta> )
+declare i64 @llvm.atomic.load.umax.i64.p0i64( i64* <ptr>, i64 <delta> )
+
+</pre>
+
+<pre>
+declare i8 @llvm.atomic.load.umin.i8..p0i8( i8* <ptr>, i8 <delta> )
+declare i16 @llvm.atomic.load.umin.i16.p0i16( i16* <ptr>, i16 <delta> )
+declare i32 @llvm.atomic.load.umin.i32..p0i32( i32* <ptr>, i32 <delta> )
+declare i64 @llvm.atomic.load.umin.i64..p0i64( i64* <ptr>, i64 <delta> )
+
+</pre>
+<h5>Overview:</h5>
+<p>
+ These intrinsics takes the signed or unsigned minimum or maximum of
+ <tt>delta</tt> and the value stored in memory at <tt>ptr</tt>. It yields the
+ original value at <tt>ptr</tt>.
+</p>
+<h5>Arguments:</h5>
+<p>
+
+ These intrinsics take two arguments, the first a pointer to an integer value
+ and the second an integer value. The result is also an integer value. These
+ integer types can have any bit width, but they must all have the same bit
+ width. The targets may only lower integer representations they support.
+</p>
+<h5>Semantics:</h5>
+<p>
+ These intrinsics does a series of operations atomically. They first load the
+ value stored at <tt>ptr</tt>. They then do the signed or unsigned min or max
+ <tt>delta</tt> and the value, store the result to <tt>ptr</tt>. They yield
+ the original value stored at <tt>ptr</tt>.
+</p>
+
+<h5>Examples:</h5>
+<pre>
+%ptr = malloc i32
+ store i32 7, %ptr
+%result0 = call i32 @llvm.atomic.load.min.i32.p0i32( i32* %ptr, i32 -2 )
+ <i>; yields {i32}:result0 = 7</i>
+%result1 = call i32 @llvm.atomic.load.max.i32.p0i32( i32* %ptr, i32 8 )
+ <i>; yields {i32}:result1 = -2</i>
+%result2 = call i32 @llvm.atomic.load.umin.i32.p0i32( i32* %ptr, i32 10 )
+ <i>; yields {i32}:result2 = 8</i>
+%result3 = call i32 @llvm.atomic.load.umax.i32.p0i32( i32* %ptr, i32 30 )
+ <i>; yields {i32}:result3 = 8</i>
+%memval1 = load i32* %ptr <i>; yields {i32}:memval1 = 30</i>
+</pre>
+</div>
<!-- ======================================================================= -->
<div class="doc_subsection">
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.
+</p>
</div>
<!-- _______________________________________________________________________ -->
</p>
</div>
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="int_stackprotector">'<tt>llvm.stackprotector</tt>' Intrinsic</a>
+</div>
+<div class="doc_text">
+<h5>Syntax:</h5>
+<pre>
+declare void @llvm.stackprotector( i8* <guard>, i8** <slot> )
+
+</pre>
+<h5>Overview:</h5>
+<p>
+ The <tt>llvm.stackprotector</tt> intrinsic takes the <tt>guard</tt> and stores
+ it onto the stack at <tt>slot</tt>. The stack slot is adjusted to ensure that
+ it is placed on the stack before local variables.
+</p>
+<h5>Arguments:</h5>
+<p>
+ The <tt>llvm.stackprotector</tt> intrinsic requires two pointer arguments. The
+ first argument is the value loaded from the stack guard
+ <tt>@__stack_chk_guard</tt>. The second variable is an <tt>alloca</tt> that
+ has enough space to hold the value of the guard.
+</p>
+<h5>Semantics:</h5>
+<p>
+ This intrinsic causes the prologue/epilogue inserter to force the position of
+ the <tt>AllocaInst</tt> stack slot to be before local variables on the
+ stack. This is to ensure that if a local variable on the stack is overwritten,
+ it will destroy the value of the guard. When the function exits, the guard on
+ the stack is checked against the original guard. If they're different, then
+ the program aborts by calling the <tt>__stack_chk_fail()</tt> function.
+</p>
+</div>
+
<!-- *********************************************************************** -->
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projects / oota-llvm.git / blobdiff