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-<tr><td> <font size=+5 color="#EEEEFF" face="Georgia,Palatino,Times,Roman"><b>LLVM Language Reference Manual</b></font></td>
-</tr></table>
-
+<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
+<html>
+<head>
+ <title>LLVM Assembly Language Reference Manual</title>
+ <link rel="stylesheet" href="llvm.css" type="text/css">
+</head>
+<body>
+<div class="doc_title"> LLVM Language Reference Manual </div>
<ol>
- <li><a href="#abstract">Abstract</a>
- <li><a href="#introduction">Introduction</a>
- <li><a href="#identifiers">Identifiers</a>
+ <li><a href="#abstract">Abstract</a></li>
+ <li><a href="#introduction">Introduction</a></li>
+ <li><a href="#identifiers">Identifiers</a></li>
<li><a href="#typesystem">Type System</a>
<ol>
- <li><a href="#t_primitive">Primitive Types</a>
- <ol>
- <li><a href="#t_classifications">Type Classifications</a>
+ <li><a href="#t_primitive">Primitive Types</a>
+ <ol>
+ <li><a href="#t_classifications">Type Classifications</a></li>
</ol>
+ </li>
<li><a href="#t_derived">Derived Types</a>
<ol>
- <li><a href="#t_array" >Array Type</a>
- <li><a href="#t_function">Function Type</a>
- <li><a href="#t_pointer">Pointer Type</a>
- <li><a href="#t_struct" >Structure Type</a>
- <!-- <li><a href="#t_packed" >Packed Type</a> -->
+ <li><a href="#t_array">Array Type</a></li>
+ <li><a href="#t_function">Function Type</a></li>
+ <li><a href="#t_pointer">Pointer Type</a></li>
+ <li><a href="#t_struct">Structure Type</a></li>
+<!-- <li><a href="#t_packed" >Packed Type</a> -->
</ol>
+ </li>
</ol>
+ </li>
<li><a href="#highlevel">High Level Structure</a>
<ol>
- <li><a href="#modulestructure">Module Structure</a>
- <li><a href="#globalvars">Global Variables</a>
- <li><a href="#functionstructure">Function Structure</a>
+ <li><a href="#modulestructure">Module Structure</a></li>
+ <li><a href="#globalvars">Global Variables</a></li>
+ <li><a href="#functionstructure">Function Structure</a></li>
</ol>
+ </li>
<li><a href="#instref">Instruction Reference</a>
<ol>
<li><a href="#terminators">Terminator Instructions</a>
<ol>
- <li><a href="#i_ret" >'<tt>ret</tt>' Instruction</a>
- <li><a href="#i_br" >'<tt>br</tt>' Instruction</a>
- <li><a href="#i_switch">'<tt>switch</tt>' Instruction</a>
- <li><a href="#i_invoke">'<tt>invoke</tt>' Instruction</a>
+ <li><a href="#i_ret">'<tt>ret</tt>' Instruction</a></li>
+ <li><a href="#i_br">'<tt>br</tt>' Instruction</a></li>
+ <li><a href="#i_switch">'<tt>switch</tt>' Instruction</a></li>
+ <li><a href="#i_invoke">'<tt>invoke</tt>' Instruction</a></li>
+ <li><a href="#i_unwind">'<tt>unwind</tt>' Instruction</a></li>
</ol>
+ </li>
<li><a href="#binaryops">Binary Operations</a>
<ol>
- <li><a href="#i_add" >'<tt>add</tt>' Instruction</a>
- <li><a href="#i_sub" >'<tt>sub</tt>' Instruction</a>
- <li><a href="#i_mul" >'<tt>mul</tt>' Instruction</a>
- <li><a href="#i_div" >'<tt>div</tt>' Instruction</a>
- <li><a href="#i_rem" >'<tt>rem</tt>' Instruction</a>
- <li><a href="#i_setcc">'<tt>set<i>cc</i></tt>' Instructions</a>
+ <li><a href="#i_add">'<tt>add</tt>' Instruction</a></li>
+ <li><a href="#i_sub">'<tt>sub</tt>' Instruction</a></li>
+ <li><a href="#i_mul">'<tt>mul</tt>' Instruction</a></li>
+ <li><a href="#i_div">'<tt>div</tt>' Instruction</a></li>
+ <li><a href="#i_rem">'<tt>rem</tt>' Instruction</a></li>
+ <li><a href="#i_setcc">'<tt>set<i>cc</i></tt>' Instructions</a></li>
</ol>
+ </li>
<li><a href="#bitwiseops">Bitwise Binary Operations</a>
<ol>
- <li><a href="#i_and">'<tt>and</tt>' Instruction</a>
- <li><a href="#i_or" >'<tt>or</tt>' Instruction</a>
- <li><a href="#i_xor">'<tt>xor</tt>' Instruction</a>
- <li><a href="#i_shl">'<tt>shl</tt>' Instruction</a>
- <li><a href="#i_shr">'<tt>shr</tt>' Instruction</a>
+ <li><a href="#i_and">'<tt>and</tt>' Instruction</a></li>
+ <li><a href="#i_or">'<tt>or</tt>' Instruction</a></li>
+ <li><a href="#i_xor">'<tt>xor</tt>' Instruction</a></li>
+ <li><a href="#i_shl">'<tt>shl</tt>' Instruction</a></li>
+ <li><a href="#i_shr">'<tt>shr</tt>' Instruction</a></li>
</ol>
+ </li>
<li><a href="#memoryops">Memory Access Operations</a>
<ol>
- <li><a href="#i_malloc" >'<tt>malloc</tt>' Instruction</a>
- <li><a href="#i_free" >'<tt>free</tt>' Instruction</a>
- <li><a href="#i_alloca" >'<tt>alloca</tt>' Instruction</a>
- <li><a href="#i_load" >'<tt>load</tt>' Instruction</a>
- <li><a href="#i_store" >'<tt>store</tt>' Instruction</a>
- <li><a href="#i_getelementptr">'<tt>getelementptr</tt>' Instruction</a>
+ <li><a href="#i_malloc">'<tt>malloc</tt>' Instruction</a></li>
+ <li><a href="#i_free">'<tt>free</tt>' Instruction</a></li>
+ <li><a href="#i_alloca">'<tt>alloca</tt>' Instruction</a></li>
+ <li><a href="#i_load">'<tt>load</tt>' Instruction</a></li>
+ <li><a href="#i_store">'<tt>store</tt>' Instruction</a></li>
+ <li><a href="#i_getelementptr">'<tt>getelementptr</tt>' Instruction</a></li>
</ol>
+ </li>
<li><a href="#otherops">Other Operations</a>
<ol>
- <li><a href="#i_phi" >'<tt>phi</tt>' Instruction</a>
- <li><a href="#i_cast">'<tt>cast .. to</tt>' Instruction</a>
- <li><a href="#i_call" >'<tt>call</tt>' Instruction</a>
- <li><a href="#i_va_arg">'<tt>va_arg</tt>' Instruction</a>
+ <li><a href="#i_phi">'<tt>phi</tt>' Instruction</a></li>
+ <li><a href="#i_cast">'<tt>cast .. to</tt>' Instruction</a></li>
+ <li><a href="#i_call">'<tt>call</tt>' Instruction</a></li>
+ <li><a href="#i_vanext">'<tt>vanext</tt>' Instruction</a></li>
+ <li><a href="#i_vaarg">'<tt>vaarg</tt>' Instruction</a></li>
</ol>
+ </li>
</ol>
+ </li>
<li><a href="#intrinsics">Intrinsic Functions</a>
- <ol>
- <li><a href="#int_varargs">Variable Argument Handling Intrinsics</a>
<ol>
- <li><a href="#i_va_start">'<tt>llvm.va_start</tt>' Intrinsic</a>
- <li><a href="#i_va_end" >'<tt>llvm.va_end</tt>' Intrinsic</a>
- <li><a href="#i_va_copy" >'<tt>llvm.va_copy</tt>' Intrinsic</a>
+ <li><a href="#int_varargs">Variable Argument Handling Intrinsics</a>
+ <ol>
+ <li><a href="#i_va_start">'<tt>llvm.va_start</tt>' Intrinsic</a></li>
+ <li><a href="#i_va_end">'<tt>llvm.va_end</tt>' Intrinsic</a></li>
+ <li><a href="#i_va_copy">'<tt>llvm.va_copy</tt>' Intrinsic</a></li>
+ </ol>
+ </li>
</ol>
- </ol>
-
- <p><b>Written by <a href="mailto:sabre@nondot.org">Chris Lattner</a> and <A href="mailto:vadve@cs.uiuc.edu">Vikram Adve</a></b><p>
-
-
+ </li>
</ol>
-
-
+<div class="doc_text">
+<p><b>Written by <a href="mailto:sabre@nondot.org">Chris Lattner</a>
+and <a href="mailto:vadve@cs.uiuc.edu">Vikram Adve</a></b></p>
+<p> </p>
+</div>
<!-- *********************************************************************** -->
-<p><table width="100%" bgcolor="#330077" border=0 cellpadding=4 cellspacing=0>
-<tr><td align=center><font color="#EEEEFF" size=+2 face="Georgia,Palatino"><b>
-<a name="abstract">Abstract
-</b></font></td></tr></table><ul>
+<div class="doc_section"> <a name="abstract">Abstract </a></div>
<!-- *********************************************************************** -->
-
-<blockquote>
- 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 representation used throughout all phases of
- the LLVM compilation strategy.
-</blockquote>
-
-
-
-
+<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
+representation used throughout all phases of the LLVM compilation
+strategy.</p>
+</div>
<!-- *********************************************************************** -->
-</ul><table width="100%" bgcolor="#330077" border=0 cellpadding=4 cellspacing=0>
-<tr><td align=center><font color="#EEEEFF" size=+2 face="Georgia,Palatino"><b>
-<a name="introduction">Introduction
-</b></font></td></tr></table><ul>
+<div class="doc_section"> <a name="introduction">Introduction</a> </div>
<!-- *********************************************************************** -->
-
-The LLVM code representation is designed to be used in three different forms: as
-an in-memory compiler IR, as an on-disk bytecode representation, suitable for
-fast loading by a dynamic compiler, and as a human readable assembly language
-representation. This allows LLVM to provide a powerful intermediate
-representation for efficient compiler transformations and analysis, while
-providing a natural means to debug and visualize the transformations. The three
-different forms of LLVM are all equivalent. This document describes the human
-readable representation and notation.<p>
-
-The LLVM representation aims to be a light weight and low level while being
-expressive, typed, and extensible at the same time. It aims to be a "universal
-IR" of sorts, by being at a low enough level that high level ideas may be
-cleanly mapped to it (similar to how microprocessors are "universal IR's",
-allowing many source languages to be mapped to them). By providing type
-information, LLVM can be used as the target of optimizations: for example,
-through pointer analysis, it can be proven that a C automatic variable is never
-accessed outside of the current function... allowing it to be promoted to a
-simple SSA value instead of a memory location.<p>
-
+<div class="doc_text">
+<p>The LLVM code representation is designed to be used in three
+different forms: as an in-memory compiler IR, as an on-disk bytecode
+representation (suitable for fast loading by a Just-In-Time compiler),
+and as a human readable assembly language representation. This allows
+LLVM to provide a powerful intermediate representation for efficient
+compiler transformations and analysis, while providing a natural means
+to debug and visualize the transformations. The three different forms
+of LLVM are all equivalent. This document describes the human readable
+representation and notation.</p>
+<p>The LLVM representation aims to be a light-weight and low-level
+while being expressive, typed, and extensible at the same time. It
+aims to be a "universal IR" of sorts, by being at a low enough level
+that high-level ideas may be cleanly mapped to it (similar to how
+microprocessors are "universal IR's", allowing many source languages to
+be mapped to them). By providing type information, LLVM can be used as
+the target of optimizations: for example, through pointer analysis, it
+can be proven that a C automatic variable is never accessed outside of
+the current function... allowing it to be promoted to a simple SSA
+value instead of a memory location.</p>
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="wellformed"><h4><hr size=0>Well Formedness</h4><ul>
-
-It is important to note that this document describes 'well formed' LLVM assembly
-language. There is a difference between what the parser accepts and what is
-considered 'well formed'. For example, the following instruction is
-syntactically okay, but not well formed:<p>
-
-<pre>
- %x = <a href="#i_add">add</a> int 1, %x
-</pre>
-
-...because the definition of <tt>%x</tt> does not dominate all of its uses. The
-LLVM infrastructure provides a verification pass that may be used to verify that
-an LLVM module is well formed. This pass is automatically run by the parser
-after parsing input assembly, and by the optimizer before it outputs bytecode.
-The violations pointed out by the verifier pass indicate bugs in transformation
-passes or input to the parser.<p>
-
-<!-- Describe the typesetting conventions here. -->
-
-
+<div class="doc_subsubsection"> <a name="wellformed">Well-Formedness</a> </div>
+<div class="doc_text">
+<p>It is important to note that this document describes 'well formed'
+LLVM assembly language. There is a difference between what the parser
+accepts and what is considered 'well formed'. For example, the
+following instruction is syntactically okay, but not well formed:</p>
+<pre> %x = <a href="#i_add">add</a> int 1, %x<br></pre>
+<p>...because the definition of <tt>%x</tt> does not dominate all of
+its uses. The LLVM infrastructure provides a verification pass that may
+be used to verify that an LLVM module is well formed. This pass is
+automatically run by the parser after parsing input assembly, and by
+the optimizer before it outputs bytecode. The violations pointed out
+by the verifier pass indicate bugs in transformation passes or input to
+the parser.</p>
+<!-- Describe the typesetting conventions here. --> </div>
<!-- *********************************************************************** -->
-</ul><table width="100%" bgcolor="#330077" border=0 cellpadding=4 cellspacing=0>
-<tr><td align=center><font color="#EEEEFF" size=+2 face="Georgia,Palatino"><b>
-<a name="identifiers">Identifiers
-</b></font></td></tr></table><ul>
+<div class="doc_section"> <a name="identifiers">Identifiers</a> </div>
<!-- *********************************************************************** -->
-
-LLVM uses three different forms of identifiers, for different purposes:<p>
-
+<div class="doc_text">
+<p>LLVM uses three different forms of identifiers, for different
+purposes:</p>
<ol>
-<li>Numeric constants are represented as you would expect: 12, -3 123.421, etc. Floating point constants have an optional hexidecimal notation.
-<li>Named values are represented as a string of characters with a '%' prefix. For example, %foo, %DivisionByZero, %a.really.long.identifier. The actual regular expression used is '<tt>%[a-zA-Z$._][a-zA-Z$._0-9]*</tt>'.
-<li>Unnamed values are represented as an unsigned numeric value with a '%' prefix. For example, %12, %2, %44.
-</ol><p>
-
-LLVM requires the values start with a '%' sign for two reasons: Compilers don't
-need to worry about name clashes with reserved words, and the set of reserved
-words may be expanded in the future without penalty. Additionally, unnamed
-identifiers allow a compiler to quickly come up with a temporary variable
-without having to avoid symbol table conflicts.<p>
-
-Reserved words in LLVM are very similar to reserved words in other languages.
-There are keywords for different opcodes ('<tt><a href="#i_add">add</a></tt>',
-'<tt><a href="#i_cast">cast</a></tt>', '<tt><a href="#i_ret">ret</a></tt>',
-etc...), for primitive type names ('<tt><a href="#t_void">void</a></tt>',
-'<tt><a href="#t_uint">uint</a></tt>', etc...), and others. These reserved
-words cannot conflict with variable names, because none of them start with a '%'
-character.<p>
-
-Here is an example of LLVM code to multiply the integer variable '<tt>%X</tt>'
-by 8:<p>
-
-The easy way:
-<pre>
- %result = <a href="#i_mul">mul</a> uint %X, 8
-</pre>
-
-After strength reduction:
-<pre>
- %result = <a href="#i_shl">shl</a> uint %X, ubyte 3
-</pre>
-
-And the hard way:
-<pre>
- <a href="#i_add">add</a> uint %X, %X <i>; yields {uint}:%0</i>
- <a href="#i_add">add</a> uint %0, %0 <i>; yields {uint}:%1</i>
- %result = <a href="#i_add">add</a> uint %1, %1
-</pre>
-
-This last way of multiplying <tt>%X</tt> by 8 illustrates several important lexical features of LLVM:<p>
-
+ <li>Numeric constants are represented as you would expect: 12, -3
+123.421, etc. Floating point constants have an optional hexidecimal
+notation.</li>
+ <li>Named values are represented as a string of characters with a '%'
+prefix. For example, %foo, %DivisionByZero,
+%a.really.long.identifier. The actual regular expression used is '<tt>%[a-zA-Z$._][a-zA-Z$._0-9]*</tt>'.
+Identifiers which require other characters in their names can be
+surrounded with quotes. In this way, anything except a <tt>"</tt>
+character can be used in a name.</li>
+ <li>Unnamed values are represented as an unsigned numeric value with
+a '%' prefix. For example, %12, %2, %44.</li>
+</ol>
+<p>LLVM requires the values start with a '%' sign for two reasons:
+Compilers don't need to worry about name clashes with reserved words,
+and the set of reserved words may be expanded in the future without
+penalty. Additionally, unnamed identifiers allow a compiler to quickly
+come up with a temporary variable without having to avoid symbol table
+conflicts.</p>
+<p>Reserved words in LLVM are very similar to reserved words in other
+languages. There are keywords for different opcodes ('<tt><a
+ href="#i_add">add</a></tt>', '<tt><a href="#i_cast">cast</a></tt>', '<tt><a
+ href="#i_ret">ret</a></tt>', etc...), for primitive type names ('<tt><a
+ href="#t_void">void</a></tt>', '<tt><a href="#t_uint">uint</a></tt>',
+etc...), and others. These reserved words cannot conflict with
+variable names, because none of them start with a '%' character.</p>
+<p>Here is an example of LLVM code to multiply the integer variable '<tt>%X</tt>'
+by 8:</p>
+<p>The easy way:</p>
+<pre> %result = <a href="#i_mul">mul</a> uint %X, 8<br></pre>
+<p>After strength reduction:</p>
+<pre> %result = <a href="#i_shl">shl</a> uint %X, ubyte 3<br></pre>
+<p>And the hard way:</p>
+<pre> <a href="#i_add">add</a> uint %X, %X <i>; yields {uint}:%0</i>
+ <a
+ href="#i_add">add</a> uint %0, %0 <i>; yields {uint}:%1</i>
+ %result = <a
+ href="#i_add">add</a> uint %1, %1<br></pre>
+<p>This last way of multiplying <tt>%X</tt> by 8 illustrates several
+important lexical features of LLVM:</p>
<ol>
-<li>Comments are delimited with a '<tt>;</tt>' and go until the end of line.
-<li>Unnamed temporaries are created when the result of a computation is not
- assigned to a named value.
-<li>Unnamed temporaries are numbered sequentially
-</ol><p>
-
-...and it also show a convention that we follow in this document. When
-demonstrating instructions, we will follow an instruction with a comment that
-defines the type and name of value produced. Comments are shown in italic
-text.<p>
-
-The one non-intuitive notation for constants is the optional hexidecimal form of
-floating point constants. For example, the form '<tt>double
+ <li>Comments are delimited with a '<tt>;</tt>' and go until the end
+of line.</li>
+ <li>Unnamed temporaries are created when the result of a computation
+is not assigned to a named value.</li>
+ <li>Unnamed temporaries are numbered sequentially</li>
+</ol>
+<p>...and it also show a convention that we follow in this document.
+When demonstrating instructions, we will follow an instruction with a
+comment that defines the type and name of value produced. Comments are
+shown in italic text.</p>
+<p>The one non-intuitive notation for constants is the optional
+hexidecimal form of floating point constants. For example, the form '<tt>double
0x432ff973cafa8000</tt>' is equivalent to (but harder to read than) '<tt>double
-4.5e+15</tt>' which is also supported by the parser. The only time hexadecimal
-floating point constants are useful (and the only time that they are generated
-by the disassembler) is when an FP constant has to be emitted that is not
-representable as a decimal floating point number exactly. For example, NaN's,
-infinities, and other special cases are represented in their IEEE hexadecimal
-format so that assembly and disassembly do not cause any bits to change in the
-constants.<p>
-
-
+4.5e+15</tt>' which is also supported by the parser. The only time
+hexadecimal floating point constants are useful (and the only time that
+they are generated by the disassembler) is when an FP constant has to
+be emitted that is not representable as a decimal floating point number
+exactly. For example, NaN's, infinities, and other special cases are
+represented in their IEEE hexadecimal format so that assembly and
+disassembly do not cause any bits to change in the constants.</p>
+</div>
<!-- *********************************************************************** -->
-</ul><table width="100%" bgcolor="#330077" border=0 cellpadding=4 cellspacing=0>
-<tr><td align=center><font color="#EEEEFF" size=+2 face="Georgia,Palatino"><b>
-<a name="typesystem">Type System
-</b></font></td></tr></table><ul>
+<div class="doc_section"> <a name="typesystem">Type System</a> </div>
<!-- *********************************************************************** -->
-
-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 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 three address code representations.<p>
-
+<div class="doc_text">
+<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
+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
+three address code representations.</p>
<!-- The written form for the type system was heavily influenced by the
syntactic problems with types in the C language<sup><a
-href="#rw_stroustrup">1</a></sup>.<p> -->
-
-
-
+href="#rw_stroustrup">1</a></sup>.<p> --> </div>
<!-- ======================================================================= -->
-</ul><table width="100%" bgcolor="#441188" border=0 cellpadding=4 cellspacing=0>
-<tr><td> </td><td width="100%"> <font color="#EEEEFF" face="Georgia,Palatino"><b>
-<a name="t_primitive">Primitive Types
-</b></font></td></tr></table><ul>
-
-The primitive types are the fundemental building blocks of the LLVM system. The
-current set of primitive types are as follows:<p>
-
-<table border=0 align=center><tr><td>
-
-<table border=1 cellspacing=0 cellpadding=4 align=center>
-<tr><td><tt>void</tt></td> <td>No value</td></tr>
-<tr><td><tt>ubyte</tt></td> <td>Unsigned 8 bit value</td></tr>
-<tr><td><tt>ushort</tt></td><td>Unsigned 16 bit value</td></tr>
-<tr><td><tt>uint</tt></td> <td>Unsigned 32 bit value</td></tr>
-<tr><td><tt>ulong</tt></td> <td>Unsigned 64 bit value</td></tr>
-<tr><td><tt>float</tt></td> <td>32 bit floating point value</td></tr>
-<tr><td><tt>label</tt></td> <td>Branch destination</td></tr>
-</table>
-
-</td><td valign=top>
-
-<table border=1 cellspacing=0 cellpadding=4 align=center>
-<tr><td><tt>bool</tt></td> <td>True or False value</td></tr>
-<tr><td><tt>sbyte</tt></td> <td>Signed 8 bit value</td></tr>
-<tr><td><tt>short</tt></td> <td>Signed 16 bit value</td></tr>
-<tr><td><tt>int</tt></td> <td>Signed 32 bit value</td></tr>
-<tr><td><tt>long</tt></td> <td>Signed 64 bit value</td></tr>
-<tr><td><tt>double</tt></td><td>64 bit floating point value</td></tr>
+<div class="doc_subsection"> <a name="t_primitive">Primitive Types</a> </div>
+<div class="doc_text">
+<p>The primitive types are the fundemental building blocks of the LLVM
+system. The current set of primitive types are as follows:</p>
+<p>
+<table border="0" align="center">
+ <tbody>
+ <tr>
+ <td>
+ <table border="1" cellspacing="0" cellpadding="4" align="center">
+ <tbody>
+ <tr>
+ <td><tt>void</tt></td>
+ <td>No value</td>
+ </tr>
+ <tr>
+ <td><tt>ubyte</tt></td>
+ <td>Unsigned 8 bit value</td>
+ </tr>
+ <tr>
+ <td><tt>ushort</tt></td>
+ <td>Unsigned 16 bit value</td>
+ </tr>
+ <tr>
+ <td><tt>uint</tt></td>
+ <td>Unsigned 32 bit value</td>
+ </tr>
+ <tr>
+ <td><tt>ulong</tt></td>
+ <td>Unsigned 64 bit value</td>
+ </tr>
+ <tr>
+ <td><tt>float</tt></td>
+ <td>32 bit floating point value</td>
+ </tr>
+ <tr>
+ <td><tt>label</tt></td>
+ <td>Branch destination</td>
+ </tr>
+ </tbody>
+ </table>
+ </td>
+ <td valign="top">
+ <table border="1" cellspacing="0" cellpadding="4" align="center"">
+ <tbody>
+ <tr>
+ <td><tt>bool</tt></td>
+ <td>True or False value</td>
+ </tr>
+ <tr>
+ <td><tt>sbyte</tt></td>
+ <td>Signed 8 bit value</td>
+ </tr>
+ <tr>
+ <td><tt>short</tt></td>
+ <td>Signed 16 bit value</td>
+ </tr>
+ <tr>
+ <td><tt>int</tt></td>
+ <td>Signed 32 bit value</td>
+ </tr>
+ <tr>
+ <td><tt>long</tt></td>
+ <td>Signed 64 bit value</td>
+ </tr>
+ <tr>
+ <td><tt>double</tt></td>
+ <td>64 bit floating point value</td>
+ </tr>
+ </tbody>
+ </table>
+ </td>
+ </tr>
+ </tbody>
</table>
-
-</td></tr></table><p>
-
-
-
+</p>
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="t_classifications"><h4><hr size=0>Type Classifications</h4><ul>
-
-These different primitive types fall into a few useful classifications:<p>
-
-<table border=1 cellspacing=0 cellpadding=4 align=center>
-<tr><td><a name="t_signed">signed</td> <td><tt>sbyte, short, int, long, float, double</tt></td></tr>
-<tr><td><a name="t_unsigned">unsigned</td><td><tt>ubyte, ushort, uint, ulong</tt></td></tr>
-<tr><td><a name="t_integer">integer</td><td><tt>ubyte, sbyte, ushort, short, uint, int, ulong, long</tt></td></tr>
-<tr><td><a name="t_integral">integral</td><td><tt>bool, ubyte, sbyte, ushort, short, uint, int, ulong, long</tt></td></tr>
-<tr><td><a name="t_floating">floating point</td><td><tt>float, double</tt></td></tr>
-<tr><td><a name="t_firstclass">first class</td><td><tt>bool, ubyte, sbyte, ushort, short,<br> uint, int, ulong, long, float, double, <a href="#t_pointer">pointer</a></tt></td></tr>
-</table><p>
-
-
-
-
-
+<div class="doc_subsubsection"> <a name="t_classifications">Type
+Classifications</a> </div>
+<div class="doc_text">
+<p>These different primitive types fall into a few useful
+classifications:</p>
+<p>
+<table border="1" cellspacing="0" cellpadding="4" align="center">
+ <tbody>
+ <tr>
+ <td><a name="t_signed">signed</a></td>
+ <td><tt>sbyte, short, int, long, float, double</tt></td>
+ </tr>
+ <tr>
+ <td><a name="t_unsigned">unsigned</a></td>
+ <td><tt>ubyte, ushort, uint, ulong</tt></td>
+ </tr>
+ <tr>
+ <td><a name="t_integer">integer</a></td>
+ <td><tt>ubyte, sbyte, ushort, short, uint, int, ulong, long</tt></td>
+ </tr>
+ <tr>
+ <td><a name="t_integral">integral</a></td>
+ <td><tt>bool, ubyte, sbyte, ushort, short, uint, int, ulong, long</tt></td>
+ </tr>
+ <tr>
+ <td><a name="t_floating">floating point</a></td>
+ <td><tt>float, double</tt></td>
+ </tr>
+ <tr>
+ <td><a name="t_firstclass">first class</a></td>
+ <td><tt>bool, ubyte, sbyte, ushort, short,<br>
+uint, int, ulong, long, float, double, <a href="#t_pointer">pointer</a></tt></td>
+ </tr>
+ </tbody>
+</table>
+</p>
+<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>
+</div>
<!-- ======================================================================= -->
-</ul><table width="100%" bgcolor="#441188" border=0 cellpadding=4 cellspacing=0><tr><td> </td><td width="100%"> <font color="#EEEEFF" face="Georgia,Palatino"><b>
-<a name="t_derived">Derived Types
-</b></font></td></tr></table><ul>
-
-The real power in LLVM comes from the derived types in the system. This is what
-allows a programmer to represent arrays, functions, pointers, and other useful
-types. Note that these derived types may be recursive: For example, it is
-possible to have a two dimensional array.<p>
-
-
-
+<div class="doc_subsection"> <a name="t_derived">Derived Types</a> </div>
+<div class="doc_text">
+<p>The real power in LLVM comes from the derived types in the system.
+This is what allows a programmer to represent arrays, functions,
+pointers, and other useful types. Note that these derived types may be
+recursive: For example, it is possible to have a two dimensional array.</p>
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="t_array"><h4><hr size=0>Array Type</h4><ul>
-
+<div class="doc_subsubsection"> <a name="t_array">Array Type</a> </div>
+<div class="doc_text">
<h5>Overview:</h5>
-
-The array type is a very simple derived type that arranges elements sequentially
-in memory. The array type requires a size (number of elements) and an
-underlying data type.<p>
-
+<p>The array type is a very simple derived type that arranges elements
+sequentially in memory. The array type requires a size (number of
+elements) and an underlying data type.</p>
<h5>Syntax:</h5>
-<pre>
- [<# elements> x <elementtype>]
-</pre>
-
-The number of elements is a constant integer value, elementtype may be any type
-with a size.<p>
-
+<pre> [<# elements> x <elementtype>]<br></pre>
+<p>The number of elements is a constant integer value, elementtype may
+be any type with a size.</p>
<h5>Examples:</h5>
-<ul>
- <tt>[40 x int ]</tt>: Array of 40 integer values.<br>
- <tt>[41 x int ]</tt>: Array of 41 integer values.<br>
- <tt>[40 x uint]</tt>: Array of 40 unsigned integer values.<p>
-</ul>
-
-Here are some examples of multidimensional arrays:<p>
-<ul>
-<table border=0 cellpadding=0 cellspacing=0>
-<tr><td><tt>[3 x [4 x int]]</tt></td><td>: 3x4 array integer values.</td></tr>
-<tr><td><tt>[12 x [10 x float]]</tt></td><td>: 2x10 array of single precision floating point values.</td></tr>
-<tr><td><tt>[2 x [3 x [4 x uint]]]</tt></td><td>: 2x3x4 array of unsigned integer values.</td></tr>
+<p> <tt>[40 x int ]</tt>: Array of 40 integer values.<br>
+<tt>[41 x int ]</tt>: Array of 41 integer values.<br>
+<tt>[40 x uint]</tt>: Array of 40 unsigned integer values.</p>
+<p> </p>
+<p>Here are some examples of multidimensional arrays:</p>
+<p>
+<table border="0" cellpadding="0" cellspacing="0">
+ <tbody>
+ <tr>
+ <td><tt>[3 x [4 x int]]</tt></td>
+ <td>: 3x4 array integer values.</td>
+ </tr>
+ <tr>
+ <td><tt>[12 x [10 x float]]</tt></td>
+ <td>: 12x10 array of single precision floating point values.</td>
+ </tr>
+ <tr>
+ <td><tt>[2 x [3 x [4 x uint]]]</tt></td>
+ <td>: 2x3x4 array of unsigned integer values.</td>
+ </tr>
+ </tbody>
</table>
-</ul>
-
-
+</p>
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="t_function"><h4><hr size=0>Function Type</h4><ul>
-
+<div class="doc_subsubsection"> <a name="t_function">Function Type</a> </div>
+<div class="doc_text">
<h5>Overview:</h5>
-
-The function type can be thought of as a function signature. It consists of a
-return type and a list of formal parameter types. Function types are usually
-used when to build virtual function tables (which are structures of pointers to
-functions), for indirect function calls, and when defining a function.<p>
-
+<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.
+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>
+<p>
+The return type of a function type cannot be an aggregate type.
+</p>
<h5>Syntax:</h5>
-<pre>
- <returntype> (<parameter list>)
-</pre>
-
-Where '<tt><parameter list></tt>' is a comma seperated 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. Note
-that there currently is no way to define a function in LLVM that takes a
-variable number of arguments, but it is possible to <b>call</b> a function that
-is vararg.<p>
-
+<pre> <returntype> (<parameter list>)<br></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.
+Variable argument functions can access their arguments with the <a
+ href="#int_varargs">variable argument handling intrinsic</a> functions.</p>
<h5>Examples:</h5>
-<ul>
-<table border=0 cellpadding=0 cellspacing=0>
-
-<tr><td><tt>int (int)</tt></td><td>: function taking an <tt>int</tt>, returning
-an <tt>int</tt></td></tr>
-
-<tr><td><tt>float (int, int *) *</tt></td><td>: <a href="#t_pointer">Pointer</a>
-to a function that takes an <tt>int</tt> and a <a href="#t_pointer">pointer</a>
-to <tt>int</tt>, returning <tt>float</tt>.</td></tr>
-
-<tr><td><tt>int (sbyte *, ...)</tt></td><td>: A vararg function that takes at
-least one <a href="#t_pointer">pointer</a> to <tt>sbyte</tt> (signed char in C),
-which returns an integer. This is the signature for <tt>printf</tt> in
-LLVM.</td></tr>
-
+<p>
+<table border="0" cellpadding="0" cellspacing="0">
+ <tbody>
+ <tr>
+ <td><tt>int (int)</tt></td>
+ <td>: function taking an <tt>int</tt>, returning an <tt>int</tt></td>
+ </tr>
+ <tr>
+ <td><tt>float (int, int *) *</tt></td>
+ <td>: <a href="#t_pointer">Pointer</a> to a function that takes
+an <tt>int</tt> and a <a href="#t_pointer">pointer</a> to <tt>int</tt>,
+returning <tt>float</tt>.</td>
+ </tr>
+ <tr>
+ <td><tt>int (sbyte *, ...)</tt></td>
+ <td>: A vararg function that takes at least one <a
+ href="#t_pointer">pointer</a> to <tt>sbyte</tt> (signed char in C),
+which returns an integer. This is the signature for <tt>printf</tt>
+in LLVM.</td>
+ </tr>
+ </tbody>
</table>
-</ul>
-
-
-
+</p>
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="t_struct"><h4><hr size=0>Structure Type</h4><ul>
-
+<div class="doc_subsubsection"> <a name="t_struct">Structure Type</a> </div>
+<div class="doc_text">
<h5>Overview:</h5>
-
-The structure type is used to represent a collection of data members together in
-memory. The packing of the field types is defined to match the ABI of the
-underlying processor. The elements of a structure may be any type that has a
-size.<p>
-
-Structures are accessed using '<tt><a href="#i_load">load</a></tt> and '<tt><a
-href="#i_store">store</a></tt>' by getting a pointer to a field with the '<tt><a
-href="#i_getelementptr">getelementptr</a></tt>' instruction.<p>
-
+<p>The structure type is used to represent a collection of data members
+together in memory. The packing of the field types is defined to match
+the ABI of the underlying processor. The elements of a structure may
+be any type that has a size.</p>
+<p>Structures are accessed using '<tt><a href="#i_load">load</a></tt>
+and '<tt><a href="#i_store">store</a></tt>' by getting a pointer to a
+field with the '<tt><a href="#i_getelementptr">getelementptr</a></tt>'
+instruction.</p>
<h5>Syntax:</h5>
-<pre>
- { <type list> }
-</pre>
-
-
+<pre> { <type list> }<br></pre>
<h5>Examples:</h5>
-<table border=0 cellpadding=0 cellspacing=0>
-
-<tr><td><tt>{ int, int, int }</tt></td><td>: a triple of three <tt>int</tt>
-values</td></tr>
-
-<tr><td><tt>{ float, int (int) * }</tt></td><td>: A pair, where the first
-element is a <tt>float</tt> and the second element is a <a
-href="#t_pointer">pointer</a> to a <a href="t_function">function</a> that takes
-an <tt>int</tt>, returning an <tt>int</tt>.</td></tr>
-
+<p>
+<table border="0" cellpadding="0" cellspacing="0">
+ <tbody>
+ <tr>
+ <td><tt>{ int, int, int }</tt></td>
+ <td>: a triple of three <tt>int</tt> values</td>
+ </tr>
+ <tr>
+ <td><tt>{ float, int (int) * }</tt></td>
+ <td>: A pair, where the first element is a <tt>float</tt> and the
+second element is a <a href="#t_pointer">pointer</a> to a <a
+ href="t_function">function</a> that takes an <tt>int</tt>, returning
+an <tt>int</tt>.</td>
+ </tr>
+ </tbody>
</table>
-
-
+</p>
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="t_pointer"><h4><hr size=0>Pointer Type</h4><ul>
-
+<div class="doc_subsubsection"> <a name="t_pointer">Pointer Type</a> </div>
+<div class="doc_text">
<h5>Overview:</h5>
-
-As in many languages, the pointer type represents a pointer or reference to
-another object, which must live in memory.<p>
-
+<p>As in many languages, the pointer type represents a pointer or
+reference to another object, which must live in memory.</p>
<h5>Syntax:</h5>
-<pre>
- <type> *
-</pre>
-
+<pre> <type> *<br></pre>
<h5>Examples:</h5>
-
-<table border=0 cellpadding=0 cellspacing=0>
-
-<tr><td><tt>[4x int]*</tt></td><td>: <a href="#t_pointer">pointer</a> to <a
-href="#t_array">array</a> of four <tt>int</tt> values</td></tr>
-
-<tr><td><tt>int (int *) *</tt></td><td>: A <a href="#t_pointer">pointer</a> to a
-<a href="t_function">function</a> that takes an <tt>int</tt>, returning an
-<tt>int</tt>.</td></tr>
-
-</table>
<p>
+<table border="0" cellpadding="0" cellspacing="0">
+ <tbody>
+ <tr>
+ <td><tt>[4x int]*</tt></td>
+ <td>: <a href="#t_pointer">pointer</a> to <a href="#t_array">array</a>
+of four <tt>int</tt> values</td>
+ </tr>
+ <tr>
+ <td><tt>int (int *) *</tt></td>
+ <td>: A <a href="#t_pointer">pointer</a> to a <a
+ href="t_function">function</a> that takes an <tt>int</tt>, returning
+an <tt>int</tt>.</td>
+ </tr>
+ </tbody>
+</table>
+</p>
+</div>
+<!-- _______________________________________________________________________ --><!--
+<div class="doc_subsubsection">
+ <a name="t_packed">Packed Type</a>
+</div>
-
-<!-- _______________________________________________________________________ -->
-<!--
-</ul><a name="t_packed"><h4><hr size=0>Packed Type</h4><ul>
+<div class="doc_text">
Mention/decide that packed types work with saturation or not. Maybe have a packed+saturated type in addition to just a packed type.<p>
Packed types should be 'nonsaturated' because standard data types are not saturated. Maybe have a saturated packed type?<p>
--->
-
-
-<!-- *********************************************************************** -->
-</ul><table width="100%" bgcolor="#330077" border=0 cellpadding=4 cellspacing=0>
-<tr><td align=center><font color="#EEEEFF" size=+2 face="Georgia,Palatino"><b>
-<a name="highlevel">High Level Structure
-</b></font></td></tr></table><ul>
-<!-- *********************************************************************** -->
-
-
-<!-- ======================================================================= -->
-</ul><table width="100%" bgcolor="#441188" border=0 cellpadding=4 cellspacing=0>
-<tr><td> </td><td width="100%"> <font color="#EEEEFF" face="Georgia,Palatino"><b>
-<a name="modulestructure">Module Structure
-</b></font></td></tr></table><ul>
-
-LLVM programs are composed of "Module"s, each of which is a translation unit of
-the input programs. Each module consists of functions, global variables, and
-symbol table entries. Modules may be combined together with the LLVM linker,
-which merges function (and global variable) definitions, resolves forward
-declarations, and merges symbol table entries. Here is an example of the "hello world" module:<p>
-
-<pre>
-<i>; Declare the string constant as a global constant...</i>
-<a href="#identifiers">%.LC0</a> = <a href="#linkage_decl">internal</a> <a href="#globalvars">constant</a> <a href="#t_array">[13 x sbyte]</a> c"hello world\0A\00" <i>; [13 x sbyte]*</i>
-
-<i>; Forward declaration of puts</i>
-<a href="#functionstructure">declare</a> int "puts"(sbyte*) <i>; int(sbyte*)* </i>
+</div>
+
+--><!-- *********************************************************************** -->
+<div class="doc_section"> <a name="highlevel">High Level Structure</a> </div>
+<!-- *********************************************************************** --><!-- ======================================================================= -->
+<div class="doc_subsection"> <a name="modulestructure">Module Structure</a> </div>
+<div class="doc_text">
+<p>LLVM programs are composed of "Module"s, each of which is a
+translation unit of the input programs. Each module consists of
+functions, global variables, and symbol table entries. Modules may be
+combined together with the LLVM linker, which merges function (and
+global variable) definitions, resolves forward declarations, and merges
+symbol table entries. Here is an example of the "hello world" module:</p>
+<pre><i>; Declare the string constant as a global constant...</i>
+<a href="#identifiers">%.LC0</a> = <a href="#linkage_internal">internal</a> <a
+ href="#globalvars">constant</a> <a href="#t_array">[13 x sbyte]</a> c"hello world\0A\00" <i>; [13 x sbyte]*</i>
+
+<i>; External declaration of the puts function</i>
+<a href="#functionstructure">declare</a> int %puts(sbyte*) <i>; int(sbyte*)* </i>
<i>; Definition of main function</i>
-int "main"() { <i>; int()* </i>
+int %main() { <i>; int()* </i>
<i>; Convert [13x sbyte]* to sbyte *...</i>
- %cast210 = <a href="#i_getelementptr">getelementptr</a> [13 x sbyte]* %.LC0, long 0, long 0 <i>; sbyte*</i>
+ %cast210 = <a
+ href="#i_getelementptr">getelementptr</a> [13 x sbyte]* %.LC0, long 0, long 0 <i>; sbyte*</i>
<i>; Call puts function to write out the string to stdout...</i>
- <a href="#i_call">call</a> int %puts(sbyte* %cast210) <i>; int</i>
- <a href="#i_ret">ret</a> int 0
-}
-</pre>
-
-This example is made up of a <a href="#globalvars">global variable</a> named
-"<tt>.LC0</tt>", an external declaration of the "<tt>puts</tt>" function, and a
-<a href="#functionstructure">function definition</a> for "<tt>main</tt>".<p>
-
-<a name="linkage_decl">
-In general, a module is made up of a list of global values, where both functions
-and global variables are global values. Global values are represented by a
-pointer to a memory location (in this case, a pointer to an array of char, and a
-pointer to a function), and can be either "internal" or externally accessible
-(which corresponds to the static keyword in C, when used at global scope).<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 external (i.e., lacking "<tt>internal</tt>"
-declarations), they are accessible outside of the current module. It is illegal
-for a function declaration to be "<tt>internal</tt>".<p>
-
-
+ <a
+ href="#i_call">call</a> int %puts(sbyte* %cast210) <i>; int</i>
+ <a
+ href="#i_ret">ret</a> int 0<br>}<br></pre>
+<p>This example is made up of a <a href="#globalvars">global variable</a>
+named "<tt>.LC0</tt>", an external declaration of the "<tt>puts</tt>"
+function, and a <a href="#functionstructure">function definition</a>
+for "<tt>main</tt>".</p>
+<a name="linkage"> In general, a module is made up of a list of global
+values, where both functions and global variables are global values.
+Global values are represented by a pointer to a memory location (in
+this case, a pointer to an array of char, and a pointer to a function),
+and have one of the following linkage types:</a>
+<p> </p>
+<dl>
+ <a name="linkage_internal"> <dt><tt><b>internal</b></tt> </dt>
+ <dd>Global values with internal 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 '<tt>static</tt>' keyword in C, or the
+idea of "anonymous namespaces" in C++.
+ <p> </p>
+ </dd>
+ </a><a name="linkage_linkonce"> <dt><tt><b>linkonce</b></tt>: </dt>
+ <dd>"<tt>linkonce</tt>" linkage is similar to <tt>internal</tt>
+linkage, with the twist that linking together two modules defining the
+same <tt>linkonce</tt> globals will cause one of the globals to be
+discarded. This is typically used to implement inline functions.
+Unreferenced <tt>linkonce</tt> globals are allowed to be discarded.
+ <p> </p>
+ </dd>
+ </a><a name="linkage_weak"> <dt><tt><b>weak</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 to implement constructs in C such as "<tt>int
+X;</tt>" at global scope.
+ <p> </p>
+ </dd>
+ </a><a name="linkage_appending"> <dt><tt><b>appending</b></tt>: </dt>
+ <dd>"<tt>appending</tt>" linkage may only be applied to global
+variables of pointer to array type. When two global variables with
+appending linkage are linked together, the two global arrays are
+appended together. This is the LLVM, typesafe, equivalent of having
+the system linker append together "sections" with identical names when
+.o files are linked.
+ <p> </p>
+ </dd>
+ </a><a name="linkage_external"> <dt><tt><b>externally visible</b></tt>:</dt>
+ <dd>If none of the above identifiers are used, the global is
+externally visible, meaning that it participates in linkage and can be
+used to resolve external symbol references.
+ <p> </p>
+ </dd>
+ </a>
+</dl>
+<p> </p>
+<p><a name="linkage_external">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
+external (i.e., lacking any linkage declarations), they are accessible
+outside of the current module. It is illegal for a function <i>declaration</i>
+to have any linkage type other than "externally visible".</a></p>
+</div>
<!-- ======================================================================= -->
-</ul><table width="100%" bgcolor="#441188" border=0 cellpadding=4 cellspacing=0>
-<tr><td> </td><td width="100%"> <font color="#EEEEFF" face="Georgia,Palatino"><b>
-<a name="globalvars">Global Variables
-</b></font></td></tr></table><ul>
-
-Global variables define regions of memory allocated at compilation time instead
-of run-time. Global variables may optionally be initialized. A variable may
-be defined as a global "constant", which indicates that the contents of the
-variable will never be modified (opening options for optimization). Constants
-must always have an initial value.<p>
-
-As SSA values, global variables define pointer values that are in scope
-(i.e. they dominate) for all basic blocks in the program. Global variables
-always define a pointer to their "content" type because they describe a region
-of memory, and all memory objects in LLVM are accessed through pointers.<p>
-
-
-
+<div class="doc_subsection"> <a name="globalvars">Global Variables</a> </div>
+<div class="doc_text">
+<p>Global variables define regions of memory allocated at compilation
+time instead of run-time. Global variables may optionally be
+initialized. A variable may be defined as a global "constant", which
+indicates that the contents of the variable will never be modified
+(opening options for optimization). Constants must always have an
+initial value.</p>
+<p>As SSA values, global variables define pointer values that are in
+scope (i.e. they dominate) for all basic blocks in the program. Global
+variables always define a pointer to their "content" type because they
+describe a region of memory, and all memory objects in LLVM are
+accessed through pointers.</p>
+</div>
<!-- ======================================================================= -->
-</ul><table width="100%" bgcolor="#441188" border=0 cellpadding=4 cellspacing=0>
-<tr><td> </td><td width="100%"> <font color="#EEEEFF" face="Georgia,Palatino"><b>
-<a name="functionstructure">Function Structure
-</b></font></td></tr></table><ul>
-
-LLVM functions definitions are composed of a (possibly empty) argument list, an
-opening curly brace, a list of basic blocks, and a closing curly brace. LLVM
-function declarations are defined with the "<tt>declare</tt>" keyword, a
-function name and a function signature.<p>
-
-A function definition contains a list of basic blocks, forming the CFG for the
-function. Each basic block may optionally start with a label (giving the 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
-return).<p>
-
-The first basic block in program is special in two ways: it is immediately
-executed on entrance to the function, and it is not allowed to have predecessor
-basic blocks (i.e. there can not be any branches to the entry block of a
-function).<p>
-
-
+<div class="doc_subsection"> <a name="functionstructure">Functions</a> </div>
+<div class="doc_text">
+<p>LLVM function definitions are composed of a (possibly empty)
+argument list, an opening curly brace, a list of basic blocks, and a
+closing curly brace. LLVM function declarations are defined with the "<tt>declare</tt>"
+keyword, a function name, and a function signature.</p>
+<p>A function definition contains a list of basic blocks, forming the
+CFG for the function. Each basic block may optionally start with a
+label (giving the 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 return).</p>
+<p>The first basic block in program is special in two ways: it is
+immediately executed on entrance to the function, and it is not allowed
+to have predecessor basic blocks (i.e. there can not be any branches to
+the entry block of a function). Because the block can have no
+predecessors, it also cannot have any <a href="#i_phi">PHI nodes</a>.</p>
+<p>
+LLVM functions are identified by their name and type signature. Hence, two
+functions with the same name but different parameter lists or return values
+are considered different functions, and LLVM will resolves references to each
+appropriately.
+</p>
+</div>
<!-- *********************************************************************** -->
-</ul><table width="100%" bgcolor="#330077" border=0 cellpadding=4 cellspacing=0>
-<tr><td align=center><font color="#EEEEFF" size=+2 face="Georgia,Palatino"><b>
-<a name="instref">Instruction Reference
-</b></font></td></tr></table><ul>
+<div class="doc_section"> <a name="instref">Instruction Reference</a> </div>
<!-- *********************************************************************** -->
-
-The LLVM instruction set consists of several different classifications of
-instructions: <a href="#terminators">terminator instructions</a>, <a
-href="#binaryops">binary instructions</a>, <a href="#memoryops">memory
-instructions</a>, and <a href="#otherops">other instructions</a>.<p>
-
-
+<div class="doc_text">
+<p>The LLVM instruction set consists of several different
+classifications of instructions: <a href="#terminators">terminator
+instructions</a>, <a href="#binaryops">binary instructions</a>, <a
+ href="#memoryops">memory instructions</a>, and <a href="#otherops">other
+instructions</a>.</p>
+</div>
<!-- ======================================================================= -->
-</ul><table width="100%" bgcolor="#441188" border=0 cellpadding=4 cellspacing=0>
-<tr><td> </td><td width="100%"> <font color="#EEEEFF" face="Georgia,Palatino"><b>
-<a name="terminators">Terminator Instructions
-</b></font></td></tr></table><ul>
-
-As mentioned <a href="#functionstructure">previously</a>, every basic block in a
-program ends with a "Terminator" instruction, which indicates which block should
-be executed after the current block is finished. These terminator instructions
-typically yield a '<tt>void</tt>' value: they produce control flow, not values
-(the one exception being the '<a href="#i_invoke"><tt>invoke</tt></a>'
-instruction).<p>
-
-There are four different terminator instructions: the '<a
-href="#i_ret"><tt>ret</tt></a>' instruction, the '<a
-href="#i_br"><tt>br</tt></a>' instruction, the '<a
-href="#i_switch"><tt>switch</tt></a>' instruction, and the '<a
-href="#i_invoke"><tt>invoke</tt></a>' instruction.<p>
-
-
+<div class="doc_subsection"> <a name="terminators">Terminator
+Instructions</a> </div>
+<div class="doc_text">
+<p>As mentioned <a href="#functionstructure">previously</a>, every
+basic block in a program ends with a "Terminator" instruction, which
+indicates which block should be executed after the current block is
+finished. These terminator instructions typically yield a '<tt>void</tt>'
+value: they produce control flow, not values (the one exception being
+the '<a href="#i_invoke"><tt>invoke</tt></a>' instruction).</p>
+<p>There are five different terminator instructions: the '<a
+ href="#i_ret"><tt>ret</tt></a>' instruction, the '<a href="#i_br"><tt>br</tt></a>'
+instruction, the '<a href="#i_switch"><tt>switch</tt></a>' instruction,
+the '<a href="#i_invoke"><tt>invoke</tt></a>' instruction, and the '<a
+ href="#i_unwind"><tt>unwind</tt></a>' instruction.</p>
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_ret"><h4><hr size=0>'<tt>ret</tt>' Instruction</h4><ul>
-
+<div class="doc_subsubsection"> <a name="i_ret">'<tt>ret</tt>'
+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>
</pre>
-
<h5>Overview:</h5>
-
-The '<tt>ret</tt>' instruction is used to return control flow (and a value) from
-a function, back to the caller.<p>
-
-There are two forms of the '<tt>ret</tt>' instructruction: one that returns a
-value and then causes control flow, and one that just causes control flow to
-occur.<p>
-
+<p>The '<tt>ret</tt>' instruction is used to return control flow (and a
+value) from a function, back to the caller.</p>
+<p>There are two forms of the '<tt>ret</tt>' instructruction: one that
+returns a value and then causes control flow, and one that just causes
+control flow to occur.</p>
<h5>Arguments:</h5>
-
-The '<tt>ret</tt>' instruction may return any '<a href="#t_firstclass">first
-class</a>' type. Notice 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 a value that does not match the return type of the function.<p>
-
+<p>The '<tt>ret</tt>' instruction may return any '<a
+ href="#t_firstclass">first class</a>' type. Notice 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 a value that does not
+match the return type of the function.</p>
<h5>Semantics:</h5>
-
-When the '<tt>ret</tt>' instruction is executed, control flow returns back to
-the calling function's context. If the instruction returns a value, that value
-shall be propagated into the calling function's data space.<p>
-
+<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
+the instruction after the call. If the caller was an "<a
+ href="#i_invoke"><tt>invoke</tt></a>" instruction, execution continues
+at the beginning "normal" of the destination block. If the instruction
+returns a value, that value shall set the call or invoke instruction's
+return value.</p>
<h5>Example:</h5>
-<pre>
- ret int 5 <i>; Return an integer value of 5</i>
+<pre> ret int 5 <i>; Return an integer value of 5</i>
ret void <i>; Return from a void function</i>
</pre>
-
-
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_br"><h4><hr size=0>'<tt>br</tt>' Instruction</h4><ul>
-
+<div class="doc_subsubsection"> <a name="i_br">'<tt>br</tt>' Instruction</a> </div>
+<div class="doc_text">
<h5>Syntax:</h5>
-<pre>
- br bool <cond>, label <iftrue>, label <iffalse>
- br label <dest> <i>; Unconditional branch</i>
+<pre> br bool <cond>, label <iftrue>, label <iffalse><br> br label <dest> <i>; Unconditional branch</i>
</pre>
-
<h5>Overview:</h5>
-
-The '<tt>br</tt>' instruction is used to cause control flow to transfer to a
-different basic block in the current function. There are two forms of this
-instruction, corresponding to a conditional branch and an unconditional
-branch.<p>
-
+<p>The '<tt>br</tt>' instruction is used to cause control flow to
+transfer to a different basic block in the current function. There are
+two forms of this instruction, corresponding to a conditional branch
+and an unconditional branch.</p>
<h5>Arguments:</h5>
-
-The conditional branch form of the '<tt>br</tt>' instruction takes a single
-'<tt>bool</tt>' value and two '<tt>label</tt>' values. The unconditional form
-of the '<tt>br</tt>' instruction takes a single '<tt>label</tt>' value as a
-target.<p>
-
+<p>The conditional branch form of the '<tt>br</tt>' instruction takes a
+single '<tt>bool</tt>' value and two '<tt>label</tt>' values. The
+unconditional form of the '<tt>br</tt>' instruction takes a single '<tt>label</tt>'
+value as a target.</p>
<h5>Semantics:</h5>
-
-Upon execution of a conditional '<tt>br</tt>' instruction, the '<tt>bool</tt>'
-argument is evaluated. If the value is <tt>true</tt>, control flows to the
-'<tt>iftrue</tt>' '<tt>label</tt>' argument. If "cond" is <tt>false</tt>,
-control flows to the '<tt>iffalse</tt>' '<tt>label</tt>' argument.<p>
-
+<p>Upon execution of a conditional '<tt>br</tt>' instruction, the '<tt>bool</tt>'
+argument is evaluated. If the value is <tt>true</tt>, control flows
+to the '<tt>iftrue</tt>' <tt>label</tt> argument. If "cond" is <tt>false</tt>,
+control flows to the '<tt>iffalse</tt>' <tt>label</tt> argument.</p>
<h5>Example:</h5>
-<pre>
-Test:
- %cond = <a href="#i_setcc">seteq</a> int %a, %b
- br bool %cond, label %IfEqual, label %IfUnequal
-IfEqual:
- <a href="#i_ret">ret</a> int 1
-IfUnequal:
- <a href="#i_ret">ret</a> int 0
-</pre>
-
-
+<pre>Test:<br> %cond = <a href="#i_setcc">seteq</a> int %a, %b<br> br bool %cond, label %IfEqual, label %IfUnequal<br>IfEqual:<br> <a
+ href="#i_ret">ret</a> int 1<br>IfUnequal:<br> <a href="#i_ret">ret</a> int 0<br></pre>
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_switch"><h4><hr size=0>'<tt>switch</tt>' Instruction</h4><ul>
-
+<div class="doc_subsubsection"> <a name="i_switch">'<tt>switch</tt>'
+Instruction</a> </div>
+<div class="doc_text">
<h5>Syntax:</h5>
-<pre>
- switch int <value>, label <defaultdest> [ int <val>, label &dest>, ... ]
-
-</pre>
-
+<pre> switch uint <value>, label <defaultdest> [ int <val>, label &dest>, ... ]<br></pre>
<h5>Overview:</h5>
-
-The '<tt>switch</tt>' instruction is used to transfer control flow to one of
-several different places. It is a generalization of the '<tt>br</tt>'
-instruction, allowing a branch to occur to one of many possible destinations.<p>
-
+<p>The '<tt>switch</tt>' instruction is used to transfer control flow
+to one of several different places. It is a generalization of the '<tt>br</tt>'
+instruction, allowing a branch to occur to one of many possible
+destinations.</p>
<h5>Arguments:</h5>
-
-The '<tt>switch</tt>' instruction uses three parameters: a '<tt>uint</tt>'
-comparison value '<tt>value</tt>', a default '<tt>label</tt>' destination, and
-an array of pairs of comparison value constants and '<tt>label</tt>'s.<p>
-
+<p>The '<tt>switch</tt>' instruction uses three parameters: a '<tt>uint</tt>'
+comparison value '<tt>value</tt>', a default '<tt>label</tt>'
+destination, and an array of pairs of comparison value constants and '<tt>label</tt>'s.</p>
<h5>Semantics:</h5>
-
-The <tt>switch</tt> instruction specifies a table of values and destinations.
-When the '<tt>switch</tt>' instruction is executed, this table is searched for
-the given value. If the value is found, the corresponding destination is
-branched to, otherwise the default value it transfered to.<p>
-
+<p>The <tt>switch</tt> instruction specifies a table of values and
+destinations. When the '<tt>switch</tt>' instruction is executed, this
+table is searched for the given value. If the value is found, the
+corresponding destination is branched to, otherwise the default value
+it transfered to.</p>
<h5>Implementation:</h5>
-
-Depending on properties of the target machine and the particular <tt>switch</tt>
-instruction, this instruction may be code generated as a series of chained
-conditional branches, or with a lookup table.<p>
-
+<p>Depending on properties of the target machine and the particular <tt>switch</tt>
+instruction, this instruction may be code generated as a series of
+chained conditional branches, or with a lookup table.</p>
<h5>Example:</h5>
-<pre>
- <i>; Emulate a conditional br instruction</i>
- %Val = <a href="#i_cast">cast</a> bool %value to uint
- switch int %Val, label %truedest [int 0, label %falsedest ]
-
- <i>; Emulate an unconditional br instruction</i>
- switch int 0, label %dest [ ]
+<pre> <i>; Emulate a conditional br instruction</i>
+ %Val = <a
+ href="#i_cast">cast</a> bool %value to uint<br> switch uint %Val, label %truedest [int 0, label %falsedest ]<br><br> <i>; Emulate an unconditional br instruction</i>
+ switch uint 0, label %dest [ ]
<i>; Implement a jump table:</i>
- switch int %val, label %otherwise [ int 0, label %onzero,
- int 1, label %onone,
- int 2, label %ontwo ]
+ switch uint %val, label %otherwise [ int 0, label %onzero,
+ int 1, label %onone,
+ int 2, label %ontwo ]
</pre>
-
-
-
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_invoke"><h4><hr size=0>'<tt>invoke</tt>' Instruction</h4><ul>
-
+<div class="doc_subsubsection"> <a name="i_invoke">'<tt>invoke</tt>'
+Instruction</a> </div>
+<div class="doc_text">
<h5>Syntax:</h5>
-<pre>
- <result> = invoke <ptr to function ty> %<function ptr val>(<function args>)
- to label <normal label> except label <exception label>
-</pre>
-
+<pre> <result> = invoke <ptr to function ty> %<function ptr val>(<function args>)<br> to label <normal label> except label <exception label><br></pre>
<h5>Overview:</h5>
-
-The '<tt>invoke</tt>' instruction is used to cause control flow to transfer to a
-specified function, with the possibility of control flow transfer to either the
-'<tt>normal label</tt>' label or the '<tt>exception label</tt>'. The '<tt><a
-href="#i_call">call</a></tt>' instruction is closely related, but guarantees
-that control flow either never returns from the called function, or that it
-returns to the instruction following the '<tt><a href="#i_call">call</a></tt>'
-instruction.<p>
-
+<p>The '<tt>invoke</tt>' instruction causes control to transfer to a
+specified function, with the possibility of control flow transfer to
+either the '<tt>normal</tt>' <tt>label</tt> label or the '<tt>exception</tt>'<tt>label</tt>.
+If the callee function returns with the "<tt><a href="#i_ret">ret</a></tt>"
+instruction, control flow will return to the "normal" label. If the
+callee (or any indirect callees) returns with the "<a href="#i_unwind"><tt>unwind</tt></a>"
+instruction, control is interrupted, and continued at the dynamically
+nearest "except" label.</p>
<h5>Arguments:</h5>
-
-This instruction requires several arguments:<p>
+<p>This instruction requires several arguments:</p>
<ol>
-
-<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
-an arbitrary pointer to function value.<p>
-
-<li>'<tt>function ptr val</tt>': An LLVM value containing a pointer to a
-function to be invoked.
-
-<li>'<tt>function args</tt>': argument list whose types match the function
-signature argument types. If the function signature indicates the function
-accepts a variable number of arguments, the extra arguments can be specified.
-
-<li>'<tt>normal label</tt>': the label reached when the called function executes
-a '<tt><a href="#i_ret">ret</a></tt>' instruction.
-
-<li>'<tt>exception label</tt>': the label reached when an exception is thrown.
+ <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 an arbitrary pointer to function value. </li>
+ <li>'<tt>function ptr val</tt>': An LLVM value containing a pointer
+to a function to be invoked. </li>
+ <li>'<tt>function args</tt>': argument list whose types match the
+function signature argument types. If the function signature indicates
+the function accepts a variable number of arguments, the extra
+arguments can be specified. </li>
+ <li>'<tt>normal label</tt>': the label reached when the called
+function executes a '<tt><a href="#i_ret">ret</a></tt>' instruction. </li>
+ <li>'<tt>exception label</tt>': the label reached when a callee
+returns with the <a href="#i_unwind"><tt>unwind</tt></a> instruction. </li>
</ol>
-
<h5>Semantics:</h5>
-
-This instruction is designed to operate as a standard '<tt><a
-href="#i_call">call</a></tt>' instruction in most regards. The primary
-difference is that it associates a label with the function invocation that may
-be accessed via the runtime library provided by the execution environment. This
-instruction is used in languages with destructors to ensure that proper cleanup
-is performed in the case of either a <tt>longjmp</tt> or a thrown exception.
-Additionally, this is important for implementation of '<tt>catch</tt>' clauses
-in high-level languages that support them.<p>
-
-<!-- For a more comprehensive explanation of how this instruction is used, look in the llvm/docs/2001-05-18-ExceptionHandling.txt document.<p> -->
-
+<p>This instruction is designed to operate as a standard '<tt><a
+ href="#i_call">call</a></tt>' instruction in most regards. The
+primary difference is that it establishes an association with a label,
+which is used by the runtime library to unwind the stack.</p>
+<p>This instruction is used in languages with destructors to ensure
+that proper cleanup is performed in the case of either a <tt>longjmp</tt>
+or a thrown exception. Additionally, this is important for
+implementation of '<tt>catch</tt>' clauses in high-level languages that
+support them.</p>
<h5>Example:</h5>
-<pre>
- %retval = invoke int %Test(int 15)
- to label %Continue except label %TestCleanup <i>; {int}:retval set</i>
+<pre> %retval = invoke int %Test(int 15)<br> to label %Continue<br> except label %TestCleanup <i>; {int}:retval set</i>
</pre>
-
-
-
+</div>
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection"> <a name="i_unwind">'<tt>unwind</tt>'
+Instruction</a> </div>
+<div class="doc_text">
+<h5>Syntax:</h5>
+<pre> unwind<br></pre>
+<h5>Overview:</h5>
+<p>The '<tt>unwind</tt>' instruction unwinds the stack, continuing
+control flow at the first callee in the dynamic call stack which used
+an <a href="#i_invoke"><tt>invoke</tt></a> instruction to perform the
+call. This is primarily used to implement exception handling.</p>
+<h5>Semantics:</h5>
+<p>The '<tt>unwind</tt>' intrinsic 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 <tt>invoke</tt> instruction. If
+there is no <tt>invoke</tt> instruction in the dynamic call chain,
+undefined behavior results.</p>
+</div>
<!-- ======================================================================= -->
-</ul><table width="100%" bgcolor="#441188" border=0 cellpadding=4 cellspacing=0><tr><td> </td><td width="100%"> <font color="#EEEEFF" face="Georgia,Palatino"><b>
-<a name="binaryops">Binary Operations
-</b></font></td></tr></table><ul>
-
-Binary operators are used to do most of the computation in a program. They
-require two operands, execute an operation on them, and produce a single value.
-The result value of a binary operator is not neccesarily the same type as its
-operands.<p>
-
-There are several different binary operators:<p>
-
-
+<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
+produce a single value. The result value of a binary operator is not
+necessarily the same type as its operands.</p>
+<p>There are several different binary operators:</p>
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_add"><h4><hr size=0>'<tt>add</tt>' Instruction</h4><ul>
-
+<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> <var1>, <var2> <i>; yields {ty}:result</i>
</pre>
-
<h5>Overview:</h5>
-The '<tt>add</tt>' instruction returns the sum of its two operands.<p>
-
+<p>The '<tt>add</tt>' instruction returns the sum of its two operands.</p>
<h5>Arguments:</h5>
-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. Both arguments must have identical types.<p>
-
+<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. Both arguments must have identical types.</p>
<h5>Semantics:</h5>
-
-The value produced is the integer or floating point sum of the two operands.<p>
-
+<p>The value produced is the integer or floating point sum of the two
+operands.</p>
<h5>Example:</h5>
-<pre>
- <result> = add int 4, %var <i>; yields {int}:result = 4 + %var</i>
+<pre> <result> = add int 4, %var <i>; yields {int}:result = 4 + %var</i>
</pre>
-
-
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_sub"><h4><hr size=0>'<tt>sub</tt>' Instruction</h4><ul>
-
+<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> <var1>, <var2> <i>; yields {ty}:result</i>
</pre>
-
<h5>Overview:</h5>
-
-The '<tt>sub</tt>' instruction returns the difference of its two operands.<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>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>
<h5>Arguments:</h5>
-
-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. Both arguments must have identical types.<p>
-
+<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. Both arguments must have identical types.</p>
<h5>Semantics:</h5>
-
-The value produced is the integer or floating point difference of the two
-operands.<p>
-
+<p>The value produced is the integer or floating point difference of
+the two operands.</p>
<h5>Example:</h5>
-<pre>
- <result> = sub int 4, %var <i>; yields {int}:result = 4 - %var</i>
+<pre> <result> = sub int 4, %var <i>; yields {int}:result = 4 - %var</i>
<result> = sub int 0, %val <i>; yields {int}:result = -%var</i>
</pre>
-
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_mul"><h4><hr size=0>'<tt>mul</tt>' Instruction</h4><ul>
-
+<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> <var1>, <var2> <i>; yields {ty}:result</i>
</pre>
-
<h5>Overview:</h5>
-The '<tt>mul</tt>' instruction returns the product of its two operands.<p>
-
+<p>The '<tt>mul</tt>' instruction returns the product of its two
+operands.</p>
<h5>Arguments:</h5>
-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. Both arguments must have identical types.<p>
-
+<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. Both arguments must have identical types.</p>
<h5>Semantics:</h5>
-
-The value produced is the integer or floating point product of the two
-operands.<p>
-
-There is no signed vs unsigned multiplication. The appropriate action is taken
-based on the type of the operand. <p>
-
-
+<p>The value produced is the integer or floating point product of the
+two operands.</p>
+<p>There is no signed vs unsigned multiplication. The appropriate
+action is taken based on the type of the operand.</p>
<h5>Example:</h5>
-<pre>
- <result> = mul int 4, %var <i>; yields {int}:result = 4 * %var</i>
+<pre> <result> = mul int 4, %var <i>; yields {int}:result = 4 * %var</i>
</pre>
-
-
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_div"><h4><hr size=0>'<tt>div</tt>' Instruction</h4><ul>
-
+<div class="doc_subsubsection"> <a name="i_div">'<tt>div</tt>'
+Instruction</a> </div>
+<div class="doc_text">
<h5>Syntax:</h5>
-<pre>
- <result> = div <ty> <var1>, <var2> <i>; yields {ty}:result</i>
+<pre> <result> = div <ty> <var1>, <var2> <i>; yields {ty}:result</i>
</pre>
-
<h5>Overview:</h5>
-
-The '<tt>div</tt>' instruction returns the quotient of its two operands.<p>
-
+<p>The '<tt>div</tt>' instruction returns the quotient of its two
+operands.</p>
<h5>Arguments:</h5>
-
-The two arguments to the '<tt>div</tt>' instruction must be either <a
-href="#t_integer">integer</a> or <a href="#t_floating">floating point</a>
-values. Both arguments must have identical types.<p>
-
+<p>The two arguments to the '<tt>div</tt>' instruction must be either <a
+ href="#t_integer">integer</a> or <a href="#t_floating">floating point</a>
+values. Both arguments must have identical types.</p>
<h5>Semantics:</h5>
-
-The value produced is the integer or floating point quotient of the two
-operands.<p>
-
+<p>The value produced is the integer or floating point quotient of the
+two operands.</p>
<h5>Example:</h5>
-<pre>
- <result> = div int 4, %var <i>; yields {int}:result = 4 / %var</i>
+<pre> <result> = div int 4, %var <i>; yields {int}:result = 4 / %var</i>
</pre>
-
-
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_rem"><h4><hr size=0>'<tt>rem</tt>' Instruction</h4><ul>
-
+<div class="doc_subsubsection"> <a name="i_rem">'<tt>rem</tt>'
+Instruction</a> </div>
+<div class="doc_text">
<h5>Syntax:</h5>
-<pre>
- <result> = rem <ty> <var1>, <var2> <i>; yields {ty}:result</i>
+<pre> <result> = rem <ty> <var1>, <var2> <i>; yields {ty}:result</i>
</pre>
-
<h5>Overview:</h5>
-The '<tt>rem</tt>' instruction returns the remainder from the division of its two operands.<p>
-
+<p>The '<tt>rem</tt>' instruction returns the remainder from the
+division of its two operands.</p>
<h5>Arguments:</h5>
-The two arguments to the '<tt>rem</tt>' instruction must be either <a href="#t_integer">integer</a> or <a href="#t_floating">floating point</a> values. Both arguments must have identical types.<p>
-
+<p>The two arguments to the '<tt>rem</tt>' instruction must be either <a
+ href="#t_integer">integer</a> or <a href="#t_floating">floating point</a>
+values. Both arguments must have identical types.</p>
<h5>Semantics:</h5>
-
-This returns the <i>remainder</i> of a division (where the result has the same
-sign as the divisor), not the <i>modulus</i> (where the result has the same sign
-as the dividend) of a value. For more information about the difference, see: <a
-href="http://mathforum.org/dr.math/problems/anne.4.28.99.html">The Math
-Forum</a>.<p>
-
+<p>This returns the <i>remainder</i> of a division (where the result
+has the same sign as the divisor), not the <i>modulus</i> (where the
+result has the same sign as the dividend) of a value. For more
+information about the difference, see: <a
+ href="http://mathforum.org/dr.math/problems/anne.4.28.99.html">The
+Math Forum</a>.</p>
<h5>Example:</h5>
-<pre>
- <result> = rem int 4, %var <i>; yields {int}:result = 4 % %var</i>
+<pre> <result> = rem int 4, %var <i>; yields {int}:result = 4 % %var</i>
</pre>
-
-
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_setcc"><h4><hr size=0>'<tt>set<i>cc</i></tt>' Instructions</h4><ul>
-
+<div class="doc_subsubsection"> <a name="i_setcc">'<tt>set<i>cc</i></tt>'
+Instructions</a> </div>
+<div class="doc_text">
<h5>Syntax:</h5>
-<pre>
- <result> = seteq <ty> <var1>, <var2> <i>; yields {bool}:result</i>
+<pre> <result> = seteq <ty> <var1>, <var2> <i>; yields {bool}:result</i>
<result> = setne <ty> <var1>, <var2> <i>; yields {bool}:result</i>
<result> = setlt <ty> <var1>, <var2> <i>; yields {bool}:result</i>
<result> = setgt <ty> <var1>, <var2> <i>; yields {bool}:result</i>
<result> = setle <ty> <var1>, <var2> <i>; yields {bool}:result</i>
<result> = setge <ty> <var1>, <var2> <i>; yields {bool}:result</i>
</pre>
-
-<h5>Overview:</h5> The '<tt>set<i>cc</i></tt>' family of instructions returns a
-boolean value based on a comparison of their two operands.<p>
-
-<h5>Arguments:</h5> The two arguments to the '<tt>set<i>cc</i></tt>'
-instructions must be of <a href="#t_firstclass">first class</a> or <a
-href="#t_pointer">pointer</a> type (it is not possible to compare
-'<tt>label</tt>'s, '<tt>array</tt>'s, '<tt>structure</tt>' or '<tt>void</tt>'
-values, etc...). Both arguments must have identical types.<p>
-
-The '<tt>setlt</tt>', '<tt>setgt</tt>', '<tt>setle</tt>', and '<tt>setge</tt>'
-instructions do not operate on '<tt>bool</tt>' typed arguments.<p>
-
+<h5>Overview:</h5>
+<p>The '<tt>set<i>cc</i></tt>' family of instructions returns a boolean
+value based on a comparison of their two operands.</p>
+<h5>Arguments:</h5>
+<p>The two arguments to the '<tt>set<i>cc</i></tt>' instructions must
+be of <a href="#t_firstclass">first class</a> type (it is not possible
+to compare '<tt>label</tt>'s, '<tt>array</tt>'s, '<tt>structure</tt>'
+or '<tt>void</tt>' values, etc...). Both arguments must have identical
+types.</p>
<h5>Semantics:</h5>
-
-The '<tt>seteq</tt>' instruction yields a <tt>true</tt> '<tt>bool</tt>' value if
-both operands are equal.<br>
-
-The '<tt>setne</tt>' instruction yields a <tt>true</tt> '<tt>bool</tt>' value if
-both operands are unequal.<br>
-
-The '<tt>setlt</tt>' instruction yields a <tt>true</tt> '<tt>bool</tt>' value if
-the first operand is less than the second operand.<br>
-
-The '<tt>setgt</tt>' instruction yields a <tt>true</tt> '<tt>bool</tt>' value if
-the first operand is greater than the second operand.<br>
-
-The '<tt>setle</tt>' instruction yields a <tt>true</tt> '<tt>bool</tt>' value if
-the first operand is less than or equal to the second operand.<br>
-
-The '<tt>setge</tt>' instruction yields a <tt>true</tt> '<tt>bool</tt>' value if
-the first operand is greater than or equal to the second operand.<p>
-
+<p>The '<tt>seteq</tt>' instruction yields a <tt>true</tt> '<tt>bool</tt>'
+value if both operands are equal.<br>
+The '<tt>setne</tt>' instruction yields a <tt>true</tt> '<tt>bool</tt>'
+value if both operands are unequal.<br>
+The '<tt>setlt</tt>' instruction yields a <tt>true</tt> '<tt>bool</tt>'
+value if the first operand is less than the second operand.<br>
+The '<tt>setgt</tt>' instruction yields a <tt>true</tt> '<tt>bool</tt>'
+value if the first operand is greater than the second operand.<br>
+The '<tt>setle</tt>' instruction yields a <tt>true</tt> '<tt>bool</tt>'
+value if the first operand is less than or equal to the second operand.<br>
+The '<tt>setge</tt>' instruction yields a <tt>true</tt> '<tt>bool</tt>'
+value if the first operand is greater than or equal to the second
+operand.</p>
<h5>Example:</h5>
-<pre>
- <result> = seteq int 4, 5 <i>; yields {bool}:result = false</i>
+<pre> <result> = seteq int 4, 5 <i>; yields {bool}:result = false</i>
<result> = setne float 4, 5 <i>; yields {bool}:result = true</i>
<result> = setlt uint 4, 5 <i>; yields {bool}:result = true</i>
<result> = setgt sbyte 4, 5 <i>; yields {bool}:result = false</i>
<result> = setle sbyte 4, 5 <i>; yields {bool}:result = true</i>
<result> = setge sbyte 4, 5 <i>; yields {bool}:result = false</i>
</pre>
-
-
-
+</div>
<!-- ======================================================================= -->
-</ul><table width="100%" bgcolor="#441188" border=0 cellpadding=4 cellspacing=0>
-<tr><td> </td><td width="100%"> <font color="#EEEEFF" face="Georgia,Palatino"><b>
-<a name="bitwiseops">Bitwise Binary Operations
-</b></font></td></tr></table><ul>
-
-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>
-
+<div class="doc_subsection"> <a name="bitwiseops">Bitwise Binary
+Operations</a> </div>
+<div class="doc_text">
+<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>
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_and"><h4><hr size=0>'<tt>and</tt>' Instruction</h4><ul>
-
+<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> <var1>, <var2> <i>; yields {ty}:result</i>
</pre>
-
<h5>Overview:</h5>
-The '<tt>and</tt>' instruction returns the bitwise logical and of its two operands.<p>
-
+<p>The '<tt>and</tt>' instruction returns the bitwise logical and of
+its two operands.</p>
<h5>Arguments:</h5>
-
-The two arguments to the '<tt>and</tt>' instruction must be <a
-href="#t_integral">integral</a> values. Both arguments must have identical
-types.<p>
-
-
+<p>The two arguments to the '<tt>and</tt>' instruction must be <a
+ href="#t_integral">integral</a> values. Both arguments must have
+identical types.</p>
<h5>Semantics:</h5>
-
-The truth table used for the '<tt>and</tt>' instruction is:<p>
-
-<center><table border=1 cellspacing=0 cellpadding=4>
-<tr><td>In0</td> <td>In1</td> <td>Out</td></tr>
-<tr><td>0</td> <td>0</td> <td>0</td></tr>
-<tr><td>0</td> <td>1</td> <td>0</td></tr>
-<tr><td>1</td> <td>0</td> <td>0</td></tr>
-<tr><td>1</td> <td>1</td> <td>1</td></tr>
-</table></center><p>
-
-
+<p>The truth table used for the '<tt>and</tt>' instruction is:</p>
+<p> </p>
+<center>
+<table border="1" cellspacing="0" cellpadding="4">
+ <tbody>
+ <tr>
+ <td>In0</td>
+ <td>In1</td>
+ <td>Out</td>
+ </tr>
+ <tr>
+ <td>0</td>
+ <td>0</td>
+ <td>0</td>
+ </tr>
+ <tr>
+ <td>0</td>
+ <td>1</td>
+ <td>0</td>
+ </tr>
+ <tr>
+ <td>1</td>
+ <td>0</td>
+ <td>0</td>
+ </tr>
+ <tr>
+ <td>1</td>
+ <td>1</td>
+ <td>1</td>
+ </tr>
+ </tbody>
+</table>
+</center>
<h5>Example:</h5>
-<pre>
- <result> = and int 4, %var <i>; yields {int}:result = 4 & %var</i>
+<pre> <result> = and int 4, %var <i>; yields {int}:result = 4 & %var</i>
<result> = and int 15, 40 <i>; yields {int}:result = 8</i>
<result> = and int 4, 8 <i>; yields {int}:result = 0</i>
</pre>
-
-
-
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_or"><h4><hr size=0>'<tt>or</tt>' Instruction</h4><ul>
-
+<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> <var1>, <var2> <i>; yields {ty}:result</i>
</pre>
-
-<h5>Overview:</h5> The '<tt>or</tt>' instruction returns the bitwise logical
-inclusive or of its two operands.<p>
-
+<h5>Overview:</h5>
+<p>The '<tt>or</tt>' instruction returns the bitwise logical inclusive
+or of its two operands.</p>
<h5>Arguments:</h5>
-
-The two arguments to the '<tt>or</tt>' instruction must be <a
-href="#t_integral">integral</a> values. Both arguments must have identical
-types.<p>
-
-
+<p>The two arguments to the '<tt>or</tt>' instruction must be <a
+ href="#t_integral">integral</a> values. Both arguments must have
+identical types.</p>
<h5>Semantics:</h5>
-
-The truth table used for the '<tt>or</tt>' instruction is:<p>
-
-<center><table border=1 cellspacing=0 cellpadding=4>
-<tr><td>In0</td> <td>In1</td> <td>Out</td></tr>
-<tr><td>0</td> <td>0</td> <td>0</td></tr>
-<tr><td>0</td> <td>1</td> <td>1</td></tr>
-<tr><td>1</td> <td>0</td> <td>1</td></tr>
-<tr><td>1</td> <td>1</td> <td>1</td></tr>
-</table></center><p>
-
-
+<p>The truth table used for the '<tt>or</tt>' instruction is:</p>
+<p> </p>
+<center>
+<table border="1" cellspacing="0" cellpadding="4">
+ <tbody>
+ <tr>
+ <td>In0</td>
+ <td>In1</td>
+ <td>Out</td>
+ </tr>
+ <tr>
+ <td>0</td>
+ <td>0</td>
+ <td>0</td>
+ </tr>
+ <tr>
+ <td>0</td>
+ <td>1</td>
+ <td>1</td>
+ </tr>
+ <tr>
+ <td>1</td>
+ <td>0</td>
+ <td>1</td>
+ </tr>
+ <tr>
+ <td>1</td>
+ <td>1</td>
+ <td>1</td>
+ </tr>
+ </tbody>
+</table>
+</center>
<h5>Example:</h5>
-<pre>
- <result> = or int 4, %var <i>; yields {int}:result = 4 | %var</i>
+<pre> <result> = or int 4, %var <i>; yields {int}:result = 4 | %var</i>
<result> = or int 15, 40 <i>; yields {int}:result = 47</i>
<result> = or int 4, 8 <i>; yields {int}:result = 12</i>
</pre>
-
-
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_xor"><h4><hr size=0>'<tt>xor</tt>' Instruction</h4><ul>
-
+<div class="doc_subsubsection"> <a name="i_xor">'<tt>xor</tt>'
+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> <var1>, <var2> <i>; yields {ty}:result</i>
</pre>
-
<h5>Overview:</h5>
-
-The '<tt>xor</tt>' instruction returns the bitwise logical exclusive or of its
-two operands.<p>
-
+<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>
-
-The two arguments to the '<tt>xor</tt>' instruction must be <a
-href="#t_integral">integral</a> values. Both arguments must have identical
-types.<p>
-
-
+<p>The two arguments to the '<tt>xor</tt>' instruction must be <a
+ href="#t_integral">integral</a> values. Both arguments must have
+identical types.</p>
<h5>Semantics:</h5>
-
-The truth table used for the '<tt>xor</tt>' instruction is:<p>
-
-<center><table border=1 cellspacing=0 cellpadding=4>
-<tr><td>In0</td> <td>In1</td> <td>Out</td></tr>
-<tr><td>0</td> <td>0</td> <td>0</td></tr>
-<tr><td>0</td> <td>1</td> <td>1</td></tr>
-<tr><td>1</td> <td>0</td> <td>1</td></tr>
-<tr><td>1</td> <td>1</td> <td>0</td></tr>
-</table></center><p>
-
-
+<p>The truth table used for the '<tt>xor</tt>' instruction is:</p>
+<p> </p>
+<center>
+<table border="1" cellspacing="0" cellpadding="4">
+ <tbody>
+ <tr>
+ <td>In0</td>
+ <td>In1</td>
+ <td>Out</td>
+ </tr>
+ <tr>
+ <td>0</td>
+ <td>0</td>
+ <td>0</td>
+ </tr>
+ <tr>
+ <td>0</td>
+ <td>1</td>
+ <td>1</td>
+ </tr>
+ <tr>
+ <td>1</td>
+ <td>0</td>
+ <td>1</td>
+ </tr>
+ <tr>
+ <td>1</td>
+ <td>1</td>
+ <td>0</td>
+ </tr>
+ </tbody>
+</table>
+</center>
+<p> </p>
<h5>Example:</h5>
-<pre>
- <result> = xor int 4, %var <i>; yields {int}:result = 4 ^ %var</i>
+<pre> <result> = xor int 4, %var <i>; yields {int}:result = 4 ^ %var</i>
<result> = xor int 15, 40 <i>; yields {int}:result = 39</i>
<result> = xor int 4, 8 <i>; yields {int}:result = 12</i>
+ <result> = xor int %V, -1 <i>; yields {int}:result = ~%V</i>
</pre>
-
-
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_shl"><h4><hr size=0>'<tt>shl</tt>' Instruction</h4><ul>
-
+<div class="doc_subsubsection"> <a name="i_shl">'<tt>shl</tt>'
+Instruction</a> </div>
+<div class="doc_text">
<h5>Syntax:</h5>
-<pre>
- <result> = shl <ty> <var1>, ubyte <var2> <i>; yields {ty}:result</i>
+<pre> <result> = shl <ty> <var1>, ubyte <var2> <i>; yields {ty}:result</i>
</pre>
-
<h5>Overview:</h5>
-
-The '<tt>shl</tt>' instruction returns the first operand shifted to the left a
-specified number of bits.
-
+<p>The '<tt>shl</tt>' instruction returns the first operand shifted to
+the left a specified number of bits.</p>
<h5>Arguments:</h5>
-
-The first argument to the '<tt>shl</tt>' instruction must be an <a
-href="#t_integer">integer</a> type. The second argument must be an
-'<tt>ubyte</tt>' type.<p>
-
+<p>The first argument to the '<tt>shl</tt>' instruction must be an <a
+ href="#t_integer">integer</a> type. The second argument must be an '<tt>ubyte</tt>'
+type.</p>
<h5>Semantics:</h5>
-
-The value produced is <tt>var1</tt> * 2<sup><tt>var2</tt></sup>.<p>
-
-
+<p>The value produced is <tt>var1</tt> * 2<sup><tt>var2</tt></sup>.</p>
<h5>Example:</h5>
-<pre>
- <result> = shl int 4, ubyte %var <i>; yields {int}:result = 4 << %var</i>
+<pre> <result> = shl int 4, ubyte %var <i>; yields {int}:result = 4 << %var</i>
<result> = shl int 4, ubyte 2 <i>; yields {int}:result = 16</i>
<result> = shl int 1, ubyte 10 <i>; yields {int}:result = 1024</i>
</pre>
-
-
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_shr"><h4><hr size=0>'<tt>shr</tt>' Instruction</h4><ul>
-
-
+<div class="doc_subsubsection"> <a name="i_shr">'<tt>shr</tt>'
+Instruction</a> </div>
+<div class="doc_text">
<h5>Syntax:</h5>
-<pre>
- <result> = shr <ty> <var1>, ubyte <var2> <i>; yields {ty}:result</i>
+<pre> <result> = shr <ty> <var1>, ubyte <var2> <i>; yields {ty}:result</i>
</pre>
-
<h5>Overview:</h5>
-The '<tt>shr</tt>' instruction returns the first operand shifted to the right a specified number of bits.
-
+<p>The '<tt>shr</tt>' instruction returns the first operand shifted to
+the right a specified number of bits.</p>
<h5>Arguments:</h5>
-The first argument to the '<tt>shr</tt>' instruction must be an <a href="#t_integer">integer</a> type. The second argument must be an '<tt>ubyte</tt>' type.<p>
-
+<p>The first argument to the '<tt>shr</tt>' instruction must be an <a
+ href="#t_integer">integer</a> type. The second argument must be an '<tt>ubyte</tt>'
+type.</p>
<h5>Semantics:</h5>
-
-If the first argument is a <a href="#t_signed">signed</a> type, the most
-significant bit is duplicated in the newly free'd bit positions. If the first
-argument is unsigned, zero bits shall fill the empty positions.<p>
-
+<p>If the first argument is a <a href="#t_signed">signed</a> type, the
+most significant bit is duplicated in the newly free'd bit positions.
+If the first argument is unsigned, zero bits shall fill the empty
+positions.</p>
<h5>Example:</h5>
-<pre>
- <result> = shr int 4, ubyte %var <i>; yields {int}:result = 4 >> %var</i>
+<pre> <result> = shr int 4, ubyte %var <i>; yields {int}:result = 4 >> %var</i>
<result> = shr uint 4, ubyte 1 <i>; yields {uint}:result = 2</i>
<result> = shr int 4, ubyte 2 <i>; yields {int}:result = 1</i>
<result> = shr sbyte 4, ubyte 3 <i>; yields {sbyte}:result = 0</i>
<result> = shr sbyte -2, ubyte 1 <i>; yields {sbyte}:result = -1</i>
</pre>
-
-
-
-
-
+</div>
<!-- ======================================================================= -->
-</ul><table width="100%" bgcolor="#441188" border=0 cellpadding=4 cellspacing=0>
-<tr><td> </td><td width="100%"> <font color="#EEEEFF" face="Georgia,Palatino"><b>
-<a name="memoryops">Memory Access Operations
-</b></font></td></tr></table><ul>
-
-Accessing memory in SSA form is, well, sticky at best. This section describes how to read, write, allocate and free memory in LLVM.<p>
-
-
+<div class="doc_subsection"> <a name="memoryops">Memory Access
+Operations</a></div>
+<div class="doc_text">
+<p>A key design point of an SSA-based representation is how it
+represents memory. In LLVM, no memory locations are in SSA form, which
+makes things very simple. This section describes how to read, write,
+allocate and free memory in LLVM.</p>
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_malloc"><h4><hr size=0>'<tt>malloc</tt>' Instruction</h4><ul>
-
+<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>, uint <NumElements> <i>; yields {type*}:result</i>
+<pre> <result> = malloc <type>, uint <NumElements> <i>; yields {type*}:result</i>
<result> = malloc <type> <i>; yields {type*}:result</i>
</pre>
-
<h5>Overview:</h5>
-The '<tt>malloc</tt>' instruction allocates memory from the system heap and returns a pointer to it.<p>
-
+<p>The '<tt>malloc</tt>' instruction allocates memory from the system
+heap and returns a pointer to it.</p>
<h5>Arguments:</h5>
-
-The the '<tt>malloc</tt>' instruction allocates
-<tt>sizeof(<type>)*NumElements</tt> bytes of memory from the operating
-system, and returns a pointer of the appropriate type to the program. The
-second form of the instruction is a shorter version of the first instruction
-that defaults to allocating one element.<p>
-
-'<tt>type</tt>' must be a sized type<p>
-
+<p>The the '<tt>malloc</tt>' instruction allocates <tt>sizeof(<type>)*NumElements</tt>
+bytes of memory from the operating system, and returns a pointer of the
+appropriate type to the program. The second form of the instruction is
+a shorter version of the first instruction that defaults to allocating
+one element.</p>
+<p>'<tt>type</tt>' must be a sized type.</p>
<h5>Semantics:</h5>
-Memory is allocated, a pointer is returned.<p>
-
+<p>Memory is allocated using the system "<tt>malloc</tt>" function, and
+a pointer is returned.</p>
<h5>Example:</h5>
-<pre>
- %array = malloc [4 x ubyte ] <i>; yields {[%4 x ubyte]*}:array</i>
+<pre> %array = malloc [4 x ubyte ] <i>; yields {[%4 x ubyte]*}:array</i>
- %size = <a href="#i_add">add</a> uint 2, 2 <i>; yields {uint}:size = uint 4</i>
+ %size = <a
+ href="#i_add">add</a> uint 2, 2 <i>; yields {uint}:size = uint 4</i>
%array1 = malloc ubyte, uint 4 <i>; yields {ubyte*}:array1</i>
%array2 = malloc [12 x ubyte], uint %size <i>; yields {[12 x ubyte]*}:array2</i>
</pre>
-
-
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_free"><h4><hr size=0>'<tt>free</tt>' Instruction</h4><ul>
-
+<div class="doc_subsubsection"> <a name="i_free">'<tt>free</tt>'
+Instruction</a> </div>
+<div class="doc_text">
<h5>Syntax:</h5>
-<pre>
- free <type> <value> <i>; yields {void}</i>
+<pre> free <type> <value> <i>; yields {void}</i>
</pre>
-
-
<h5>Overview:</h5>
-The '<tt>free</tt>' instruction returns memory back to the unused memory heap, to be reallocated in the future.<p>
-
-
+<p>The '<tt>free</tt>' instruction returns memory back to the unused
+memory heap, to be reallocated in the future.</p>
+<p> </p>
<h5>Arguments:</h5>
-
-'<tt>value</tt>' shall be a pointer value that points to a value that was
-allocated with the '<tt><a href="#i_malloc">malloc</a></tt>' instruction.<p>
-
-
+<p>'<tt>value</tt>' shall be a pointer value that points to a value
+that was allocated with the '<tt><a href="#i_malloc">malloc</a></tt>'
+instruction.</p>
<h5>Semantics:</h5>
-
-Access to the memory pointed to by the pointer is not longer defined after this instruction executes.<p>
-
+<p>Access to the memory pointed to by the pointer is not longer defined
+after this instruction executes.</p>
<h5>Example:</h5>
-<pre>
- %array = <a href="#i_malloc">malloc</a> [4 x ubyte] <i>; yields {[4 x ubyte]*}:array</i>
+<pre> %array = <a href="#i_malloc">malloc</a> [4 x ubyte] <i>; yields {[4 x ubyte]*}:array</i>
free [4 x ubyte]* %array
</pre>
-
-
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_alloca"><h4><hr size=0>'<tt>alloca</tt>' Instruction</h4><ul>
-
+<div class="doc_subsubsection"> <a name="i_alloca">'<tt>alloca</tt>'
+Instruction</a> </div>
+<div class="doc_text">
<h5>Syntax:</h5>
-<pre>
- <result> = alloca <type>, uint <NumElements> <i>; yields {type*}:result</i>
+<pre> <result> = alloca <type>, uint <NumElements> <i>; yields {type*}:result</i>
<result> = alloca <type> <i>; yields {type*}:result</i>
</pre>
-
<h5>Overview:</h5>
-
-The '<tt>alloca</tt>' instruction allocates memory on the current stack frame of
-the procedure that is live until the current function returns to its caller.<p>
-
+<p>The '<tt>alloca</tt>' instruction allocates memory on the current
+stack frame of the procedure that is live until the current function
+returns to its caller.</p>
<h5>Arguments:</h5>
-
-The the '<tt>alloca</tt>' instruction allocates
-<tt>sizeof(<type>)*NumElements</tt> bytes of memory on the runtime stack,
-returning a pointer of the appropriate type to the program. The second form of
-the instruction is a shorter version of the first that defaults to allocating
-one element.<p>
-
-'<tt>type</tt>' may be any sized type.<p>
-
+<p>The the '<tt>alloca</tt>' instruction allocates <tt>sizeof(<type>)*NumElements</tt>
+bytes of memory on the runtime stack, returning a pointer of the
+appropriate type to the program. The second form of the instruction is
+a shorter version of the first that defaults to allocating one element.</p>
+<p>'<tt>type</tt>' may be any sized type.</p>
<h5>Semantics:</h5>
-
-Memory is allocated, a pointer is returned. '<tt>alloca</tt>'d memory is
-automatically released when the function returns. The '<tt>alloca</tt>'
-instruction is commonly used to represent automatic variables that must have an
-address available, as well as spilled variables.<p>
-
+<p>Memory is allocated, a pointer is returned. '<tt>alloca</tt>'d
+memory is automatically released when the function returns. The '<tt>alloca</tt>'
+instruction is commonly used to represent automatic variables that must
+have an address available. When the function returns (either with the <tt><a
+ href="#i_ret">ret</a></tt> or <tt><a href="#i_invoke">invoke</a></tt>
+instructions), the memory is reclaimed.</p>
<h5>Example:</h5>
-<pre>
- %ptr = alloca int <i>; yields {int*}:ptr</i>
+<pre> %ptr = alloca int <i>; yields {int*}:ptr</i>
%ptr = alloca int, uint 4 <i>; yields {int*}:ptr</i>
</pre>
-
-
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_load"><h4><hr size=0>'<tt>load</tt>' Instruction</h4><ul>
-
+<div class="doc_subsubsection"> <a name="i_load">'<tt>load</tt>'
+Instruction</a> </div>
+<div class="doc_text">
<h5>Syntax:</h5>
-<pre>
- <result> = load <ty>* <pointer>
-</pre>
-
+<pre> <result> = load <ty>* <pointer><br> <result> = volatile load <ty>* <pointer><br></pre>
<h5>Overview:</h5>
-The '<tt>load</tt>' instruction is used to read from memory.<p>
-
+<p>The '<tt>load</tt>' instruction is used to read from memory.</p>
<h5>Arguments:</h5>
-
-The argument to the '<tt>load</tt>' instruction specifies the memory address to load from. The pointer must point to a <a href="t_firstclass">first class</a> type.<p>
-
+<p>The argument to the '<tt>load</tt>' instruction specifies the memory
+address to load from. The pointer must point to a <a
+ href="t_firstclass">first class</a> type. If the <tt>load</tt> is
+marked as <tt>volatile</tt> then the optimizer is not allowed to modify
+the number or order of execution of this <tt>load</tt> with other
+volatile <tt>load</tt> and <tt><a href="#i_store">store</a></tt>
+instructions. </p>
<h5>Semantics:</h5>
-
-The location of memory pointed to is loaded.
-
+<p>The location of memory pointed to is loaded.</p>
<h5>Examples:</h5>
-<pre>
- %ptr = <a href="#i_alloca">alloca</a> int <i>; yields {int*}:ptr</i>
- <a href="#i_store">store</a> int 3, int* %ptr <i>; yields {void}</i>
+<pre> %ptr = <a href="#i_alloca">alloca</a> int <i>; yields {int*}:ptr</i>
+ <a
+ href="#i_store">store</a> int 3, int* %ptr <i>; yields {void}</i>
%val = load int* %ptr <i>; yields {int}:val = int 3</i>
</pre>
-
-
-
-
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_store"><h4><hr size=0>'<tt>store</tt>' Instruction</h4><ul>
-
+<div class="doc_subsubsection"> <a name="i_store">'<tt>store</tt>'
+Instruction</a> </div>
<h5>Syntax:</h5>
-<pre>
- store <ty> <value>, <ty>* <pointer> <i>; yields {void}</i>
+<pre> store <ty> <value>, <ty>* <pointer> <i>; yields {void}</i>
+ volatile store <ty> <value>, <ty>* <pointer> <i>; yields {void}</i>
</pre>
-
<h5>Overview:</h5>
-The '<tt>store</tt>' instruction is used to write to memory.<p>
-
+<p>The '<tt>store</tt>' instruction is used to write to memory.</p>
<h5>Arguments:</h5>
-
-There are two arguments to the '<tt>store</tt>' instruction: a value to store
-and an address to store it into. The type of the '<tt><pointer></tt>'
+<p>There are two arguments to the '<tt>store</tt>' instruction: a value
+to store and an address to store it into. The type of the '<tt><pointer></tt>'
operand must be a pointer to the type of the '<tt><value></tt>'
-operand.<p>
-
-<h5>Semantics:</h5> The contents of memory are updated to contain
-'<tt><value></tt>' at the location specified by the
-'<tt><pointer></tt>' operand.<p>
-
+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>
+<h5>Semantics:</h5>
+<p>The contents of memory are updated to contain '<tt><value></tt>'
+at the location specified by the '<tt><pointer></tt>' operand.</p>
<h5>Example:</h5>
-<pre>
- %ptr = <a href="#i_alloca">alloca</a> int <i>; yields {int*}:ptr</i>
- <a href="#i_store">store</a> int 3, int* %ptr <i>; yields {void}</i>
+<pre> %ptr = <a href="#i_alloca">alloca</a> int <i>; yields {int*}:ptr</i>
+ <a
+ href="#i_store">store</a> int 3, int* %ptr <i>; yields {void}</i>
%val = load int* %ptr <i>; yields {int}:val = int 3</i>
</pre>
-
-
-
-
<!-- _______________________________________________________________________ -->
-</ul><a name="i_getelementptr"><h4><hr size=0>'<tt>getelementptr</tt>' Instruction</h4><ul>
-
+<div class="doc_subsubsection"> <a name="i_getelementptr">'<tt>getelementptr</tt>'
+Instruction</a> </div>
+<div class="doc_text">
<h5>Syntax:</h5>
-<pre>
- <result> = getelementptr <ty>* <ptrval>{, long <aidx>|, ubyte <sidx>}*
-</pre>
-
+<pre> <result> = getelementptr <ty>* <ptrval>{, long <aidx>|, ubyte <sidx>}*<br></pre>
<h5>Overview:</h5>
-
-The '<tt>getelementptr</tt>' instruction is used to get the address of a
-subelement of an aggregate data structure.<p>
-
+<p>The '<tt>getelementptr</tt>' instruction is used to get the address
+of a subelement of an aggregate data structure.</p>
<h5>Arguments:</h5>
-
-This instruction takes a list of <tt>long</tt> values and <tt>ubyte</tt>
-constants that indicate what form of addressing to perform. 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.<p>
-
-For example, lets consider a C code fragment and how it gets compiled to
-LLVM:<p>
-
-<pre>
-struct RT {
- char A;
- int B[10][20];
- char C;
-};
-struct ST {
- int X;
- double Y;
- struct RT Z;
-};
-
-int *foo(struct ST *s) {
- return &s[1].Z.B[5][13];
-}
-</pre>
-
-The LLVM code generated by the GCC frontend is:
-
-<pre>
-%RT = type { sbyte, [10 x [20 x int]], sbyte }
-%ST = type { int, double, %RT }
-
-int* "foo"(%ST* %s) {
- %reg = getelementptr %ST* %s, long 1, ubyte 2, ubyte 1, long 5, long 13
- ret int* %reg
-}
-</pre>
-
+<p>This instruction takes a list of <tt>long</tt> values and <tt>ubyte</tt>
+constants that indicate what form of addressing to perform. 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.</p>
+<p>For example, let's consider a C code fragment and how it gets
+compiled to LLVM:</p>
+<pre>struct RT {<br> char A;<br> int B[10][20];<br> char C;<br>};<br>struct ST {<br> int X;<br> double Y;<br> struct RT Z;<br>};<br><br>int *foo(struct ST *s) {<br> return &s[1].Z.B[5][13];<br>}<br></pre>
+<p>The LLVM code generated by the GCC frontend is:</p>
+<pre>%RT = type { sbyte, [10 x [20 x int]], sbyte }<br>%ST = type { int, double, %RT }<br><br>int* "foo"(%ST* %s) {<br> %reg = getelementptr %ST* %s, long 1, ubyte 2, ubyte 1, long 5, long 13<br> ret int* %reg<br>}<br></pre>
<h5>Semantics:</h5>
-
-The index types specified for the '<tt>getelementptr</tt>' instruction depend on
-the pointer type that is being index into. <a href="t_pointer">Pointer</a> and
-<a href="t_array">array</a> types require '<tt>long</tt>' values, and <a
-href="t_struct">structure</a> types require '<tt>ubyte</tt>'
-<b>constants</b>.<p>
-
-In the example above, the first index is indexing into the '<tt>%ST*</tt>' type,
-which is a pointer, yielding a '<tt>%ST</tt>' = '<tt>{ int, double, %RT }</tt>'
-type, a structure. The second index indexes into the third element of the
-structure, yielding a '<tt>%RT</tt>' = '<tt>{ sbyte, [10 x [20 x int]], sbyte
-}</tt>' type, another structure. The third index indexes into the second
-element of the structure, yielding a '<tt>[10 x [20 x int]]</tt>' type, an
-array. The two dimensions of the array are subscripted into, yielding an
-'<tt>int</tt>' type. The '<tt>getelementptr</tt>' instruction return a pointer
-to this element, thus yielding a '<tt>int*</tt>' type.<p>
-
-Note that it is perfectly legal to index partially through a structure,
-returning a pointer to an inner element. Because of this, the LLVM code for the
-given testcase is equivalent to:<p>
-
-<pre>
-int* "foo"(%ST* %s) {
- %t1 = getelementptr %ST* %s , long 1 <i>; yields %ST*:%t1</i>
+<p>The index types specified for the '<tt>getelementptr</tt>'
+instruction depend on the pointer type that is being index into. <a
+ href="t_pointer">Pointer</a> and <a href="t_array">array</a> types
+require '<tt>long</tt>' values, and <a href="t_struct">structure</a>
+types require '<tt>ubyte</tt>' <b>constants</b>.</p>
+<p>In the example above, the first index is indexing into the '<tt>%ST*</tt>'
+type, which is a pointer, yielding a '<tt>%ST</tt>' = '<tt>{ int,
+double, %RT }</tt>' type, a structure. The second index indexes into
+the third element of the structure, yielding a '<tt>%RT</tt>' = '<tt>{
+sbyte, [10 x [20 x int]], sbyte }</tt>' type, another structure. The
+third index indexes into the second element of the structure, yielding
+a '<tt>[10 x [20 x int]]</tt>' type, an array. The two dimensions of
+the array are subscripted into, yielding an '<tt>int</tt>' type. The '<tt>getelementptr</tt>'
+instruction return a pointer to this element, thus yielding a '<tt>int*</tt>'
+type.</p>
+<p>Note that it is perfectly legal to index partially through a
+structure, returning a pointer to an inner element. Because of this,
+the LLVM code for the given testcase is equivalent to:</p>
+<pre>int* "foo"(%ST* %s) {<br> %t1 = getelementptr %ST* %s , long 1 <i>; yields %ST*:%t1</i>
%t2 = getelementptr %ST* %t1, long 0, ubyte 2 <i>; yields %RT*:%t2</i>
%t3 = getelementptr %RT* %t2, long 0, ubyte 1 <i>; yields [10 x [20 x int]]*:%t3</i>
%t4 = getelementptr [10 x [20 x int]]* %t3, long 0, long 5 <i>; yields [20 x int]*:%t4</i>
ret int* %t5
}
</pre>
-
-
-
<h5>Example:</h5>
-<pre>
- <i>; yields [12 x ubyte]*:aptr</i>
- %aptr = getelementptr {int, [12 x ubyte]}* %sptr, long 0, ubyte 1
-</pre>
-
-
-
+<pre> <i>; yields [12 x ubyte]*:aptr</i>
+ %aptr = getelementptr {int, [12 x ubyte]}* %sptr, long 0, ubyte 1<br></pre>
+<h5> Note To The Novice:</h5>
+When using indexing into global arrays with the '<tt>getelementptr</tt>'
+instruction, you must remember that the </div>
<!-- ======================================================================= -->
-</ul><table width="100%" bgcolor="#441188" border=0 cellpadding=4 cellspacing=0>
-<tr><td> </td><td width="100%"> <font color="#EEEEFF" face="Georgia,Palatino"><b>
-<a name="otherops">Other Operations
-</b></font></td></tr></table><ul>
-
-The instructions in this catagory are the "miscellaneous" functions, that defy better classification.<p>
-
-
+<div class="doc_subsection"> <a name="otherops">Other Operations</a> </div>
+<div class="doc_text">
+<p>The instructions in this catagory are the "miscellaneous"
+instructions, which defy better classification.</p>
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_phi"><h4><hr size=0>'<tt>phi</tt>' Instruction</h4><ul>
-
+<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>], ...
-</pre>
-
+<pre> <result> = phi <ty> [ <val0>, <label0>], ...<br></pre>
<h5>Overview:</h5>
-
-The '<tt>phi</tt>' instruction is used to implement the φ node in the SSA
-graph representing the function.<p>
-
+<p>The '<tt>phi</tt>' instruction is used to implement the φ node in
+the SSA graph representing the function.</p>
<h5>Arguments:</h5>
-
-The type of the incoming values are specified with the first type field. After
-this, the '<tt>phi</tt>' instruction takes a list of pairs as arguments, with
-one pair for each predecessor basic block of the current block.<p>
-
-There must be no non-phi instructions between the start of a basic block and the
-PHI instructions: i.e. PHI instructions must be first in a basic block.<p>
-
+<p>The type of the incoming values are specified with the first type
+field. After this, the '<tt>phi</tt>' instruction takes a list of pairs
+as arguments, with one pair for each predecessor basic block of the
+current block. Only values of <a href="#t_firstclass">first class</a>
+type may be used as the value arguments to the PHI node. Only labels
+may be used as the label arguments.</p>
+<p>There must be no non-phi instructions between the start of a basic
+block and the PHI instructions: i.e. PHI instructions must be first in
+a basic block.</p>
<h5>Semantics:</h5>
-
-At runtime, the '<tt>phi</tt>' instruction logically takes on the value
-specified by the parameter, depending on which basic block we came from in the
-last <a href="#terminators">terminator</a> instruction.<p>
-
+<p>At runtime, the '<tt>phi</tt>' instruction logically takes on the
+value specified by the parameter, depending on which basic block we
+came from in the last <a href="#terminators">terminator</a> instruction.</p>
<h5>Example:</h5>
-
-<pre>
-Loop: ; Infinite loop that counts from 0 on up...
- %indvar = phi uint [ 0, %LoopHeader ], [ %nextindvar, %Loop ]
- %nextindvar = add uint %indvar, 1
- br label %Loop
-</pre>
-
-
+<pre>Loop: ; Infinite loop that counts from 0 on up...<br> %indvar = phi uint [ 0, %LoopHeader ], [ %nextindvar, %Loop ]<br> %nextindvar = add uint %indvar, 1<br> br label %Loop<br></pre>
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_cast"><h4><hr size=0>'<tt>cast .. to</tt>' Instruction</h4><ul>
-
+<div class="doc_subsubsection"> <a name="i_cast">'<tt>cast .. to</tt>'
+Instruction</a> </div>
+<div class="doc_text">
<h5>Syntax:</h5>
-<pre>
- <result> = cast <ty> <value> to <ty2> <i>; yields ty2</i>
+<pre> <result> = cast <ty> <value> to <ty2> <i>; yields ty2</i>
</pre>
-
<h5>Overview:</h5>
-
-The '<tt>cast</tt>' instruction is used as the primitive means to convert
-integers to floating point, change data type sizes, and break type safety (by
-casting pointers).<p>
-
+<p>The '<tt>cast</tt>' instruction is used as the primitive means to
+convert integers to floating point, change data type sizes, and break
+type safety (by casting pointers).</p>
<h5>Arguments:</h5>
-
-The '<tt>cast</tt>' instruction takes a value to cast, which must be a first
-class value, and a type to cast it to, which must also be a first class type.<p>
-
+<p>The '<tt>cast</tt>' instruction takes a value to cast, which must be
+a first class value, and a type to cast it to, which must also be a <a
+ href="#t_firstclass">first class</a> type.</p>
<h5>Semantics:</h5>
-
-This instruction follows the C rules for explicit casts when determining how the
-data being cast must change to fit in its new container.<p>
-
-When casting to bool, any value that would be considered true in the context of
-a C '<tt>if</tt>' condition is converted to the boolean '<tt>true</tt>' values,
-all else are '<tt>false</tt>'.<p>
-
-When extending an integral value from a type of one signness to another (for
-example '<tt>sbyte</tt>' to '<tt>ulong</tt>'), the value is sign-extended if the
-<b>source</b> value is signed, and zero-extended if the source value is
-unsigned. <tt>bool</tt> values are always zero extended into either zero or
-one.<p>
-
+<p>This instruction follows the C rules for explicit casts when
+determining how the data being cast must change to fit in its new
+container.</p>
+<p>When casting to bool, any value that would be considered true in the
+context of a C '<tt>if</tt>' condition is converted to the boolean '<tt>true</tt>'
+values, all else are '<tt>false</tt>'.</p>
+<p>When extending an integral value from a type of one signness to
+another (for example '<tt>sbyte</tt>' to '<tt>ulong</tt>'), the value
+is sign-extended if the <b>source</b> value is signed, and
+zero-extended if the source value is unsigned. <tt>bool</tt> values
+are always zero extended into either zero or one.</p>
<h5>Example:</h5>
-<pre>
- %X = cast int 257 to ubyte <i>; yields ubyte:1</i>
+<pre> %X = cast int 257 to ubyte <i>; yields ubyte:1</i>
%Y = cast int 123 to bool <i>; yields bool:true</i>
</pre>
-
-
-
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_call"><h4><hr size=0>'<tt>call</tt>' Instruction</h4><ul>
-
+<div class="doc_subsubsection"> <a name="i_call">'<tt>call</tt>'
+Instruction</a> </div>
+<div class="doc_text">
<h5>Syntax:</h5>
-<pre>
- <result> = call <ty>* <fnptrval>(<param list>)
-</pre>
-
+<pre> <result> = call <ty>* <fnptrval>(<param list>)<br></pre>
<h5>Overview:</h5>
-
-The '<tt>call</tt>' instruction represents a simple function call.<p>
-
+<p>The '<tt>call</tt>' instruction represents a simple function call.</p>
<h5>Arguments:</h5>
-
-This instruction requires several arguments:<p>
+<p>This instruction requires several arguments:</p>
<ol>
-
-<li>'<tt>ty</tt>': shall be the signature of the pointer to function value being
-invoked. The argument types must match the types implied by this signature.<p>
-
-<li>'<tt>fnptrval</tt>': An LLVM value containing a pointer to a function to be
-invoked. In most cases, this is a direct function invocation, but indirect
-<tt>call</tt>s are just as possible, calling an arbitrary pointer to function
-values.<p>
-
-<li>'<tt>function args</tt>': argument list whose types match the function
-signature argument types. If the function signature indicates the function
-accepts a variable number of arguments, the extra arguments can be specified.
+ <li>
+ <p>'<tt>ty</tt>': shall be the signature of the pointer to function
+value being invoked. The argument types must match the types implied
+by this signature.</p>
+ </li>
+ <li>
+ <p>'<tt>fnptrval</tt>': An LLVM value containing a pointer to a
+function to be invoked. In most cases, this is a direct function
+invocation, but indirect <tt>call</tt>s are just as possible,
+calling an arbitrary pointer to function values.</p>
+ </li>
+ <li>
+ <p>'<tt>function args</tt>': argument list whose types match the
+function signature argument types. If the function signature
+indicates the function accepts a variable number of arguments, the
+extra arguments can be specified.</p>
+ </li>
</ol>
-
<h5>Semantics:</h5>
-
-The '<tt>call</tt>' instruction is used to cause control flow to transfer to a
-specified function, with its incoming arguments bound to 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. This is a simpler
-case of the <a href="#i_invoke">invoke</a> instruction.<p>
-
+<p>The '<tt>call</tt>' instruction is used to cause control flow to
+transfer to a specified function, with its incoming arguments bound to
+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. This is a simpler case of
+the <a href="#i_invoke">invoke</a> instruction.</p>
<h5>Example:</h5>
-<pre>
- %retval = call int %test(int %argc)
- call int(sbyte*, ...) *%printf(sbyte* %msg, int 12, sbyte 42);
-
-</pre>
-
+<pre> %retval = call int %test(int %argc)<br> call int(sbyte*, ...) *%printf(sbyte* %msg, int 12, sbyte 42);<br></pre>
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_va_arg"><h4><hr size=0>'<tt>va_arg</tt>' Instruction</h4><ul>
-
+<div class="doc_subsubsection"> <a name="i_vanext">'<tt>vanext</tt>'
+Instruction</a> </div>
+<div class="doc_text">
<h5>Syntax:</h5>
-<pre>
- <result> = va_arg <va_list>* <arglist>, <retty>
-</pre>
-
+<pre> <resultarglist> = vanext <va_list> <arglist>, <argty><br></pre>
<h5>Overview:</h5>
-
-The '<tt>va_arg</tt>' instruction is used to access arguments passed through the
-"variable argument" area of a function call. It corresponds directly to the
-<tt>va_arg</tt> macro in C.<p>
-
+<p>The '<tt>vanext</tt>' instruction is used to access arguments passed
+through the "variable argument" area of a function call. It is used to
+implement the <tt>va_arg</tt> macro in C.</p>
<h5>Arguments:</h5>
-
-This instruction takes a pointer to a <tt>valist</tt> value to read a new
-argument from. The return type of the instruction is defined by the second
-argument, a type.<p>
-
+<p>This instruction takes a <tt>valist</tt> value and the type of the
+argument. It returns another <tt>valist</tt>.</p>
<h5>Semantics:</h5>
-
-The '<tt>va_arg</tt>' instruction works just like the <tt>va_arg</tt> macro
-available in C. In a target-dependent way, it reads the argument indicated by
-the value the arglist points to, updates the arglist, then returns a value of
-the specified type. This instruction should be used in conjunction with the
-variable argument handling <a href="#int_varargs">Intrinsic Functions</a>.<p>
-
-It is legal for this instruction to be called in a function which does not take
-a variable number of arguments, for example, the <tt>vfprintf</tt> function.<p>
-
-<tt>va_arg</tt> is an LLVM instruction instead of an <a
-href="#intrinsics">intrinsic function</a> because the return type depends on an
-argument.<p>
-
+<p>The '<tt>vanext</tt>' instruction advances the specified <tt>valist</tt>
+past an argument of the specified type. In conjunction with the <a
+ href="#i_vaarg"><tt>vaarg</tt></a> instruction, it is used to implement
+the <tt>va_arg</tt> macro available in C. For more information, see
+the variable argument handling <a href="#int_varargs">Intrinsic
+Functions</a>.</p>
+<p>It is legal for this instruction to be called in a function which
+does not take a variable number of arguments, for example, the <tt>vfprintf</tt>
+function.</p>
+<p><tt>vanext</tt> is an LLVM instruction instead of an <a
+ href="#intrinsics">intrinsic function</a> because it takes an type as
+an argument.</p>
<h5>Example:</h5>
-
-See the <a href="#int_varargs">variable argument processing</a> section.<p>
-
+<p>See the <a href="#int_varargs">variable argument processing</a>
+section.</p>
+</div>
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection"> <a name="i_vaarg">'<tt>vaarg</tt>'
+Instruction</a> </div>
+<div class="doc_text">
+<h5>Syntax:</h5>
+<pre> <resultval> = vaarg <va_list> <arglist>, <argty><br></pre>
+<h5>Overview:</h5>
+<p>The '<tt>vaarg</tt>' instruction is used to access arguments passed
+through the "variable argument" area of a function call. It is used to
+implement the <tt>va_arg</tt> macro in C.</p>
+<h5>Arguments:</h5>
+<p>This instruction takes a <tt>valist</tt> value and the type of the
+argument. It returns a value of the specified argument type.</p>
+<h5>Semantics:</h5>
+<p>The '<tt>vaarg</tt>' instruction loads an argument of the specified
+type from the specified <tt>va_list</tt>. In conjunction with the <a
+ href="#i_vanext"><tt>vanext</tt></a> instruction, it is used to
+implement the <tt>va_arg</tt> macro available in C. For more
+information, see the variable argument handling <a href="#int_varargs">Intrinsic
+Functions</a>.</p>
+<p>It is legal for this instruction to be called in a function which
+does not take a variable number of arguments, for example, the <tt>vfprintf</tt>
+function.</p>
+<p><tt>vaarg</tt> is an LLVM instruction instead of an <a
+ href="#intrinsics">intrinsic function</a> because it takes an type as
+an argument.</p>
+<h5>Example:</h5>
+<p>See the <a href="#int_varargs">variable argument processing</a>
+section.</p>
+</div>
<!-- *********************************************************************** -->
-</ul><table width="100%" bgcolor="#330077" border=0 cellpadding=4 cellspacing=0>
-<tr><td align=center><font color="#EEEEFF" size=+2 face="Georgia,Palatino"><b>
-<a name="intrinsics">Intrinsic Functions
-</b></font></td></tr></table><ul>
+<div class="doc_section"> <a name="intrinsics">Intrinsic Functions</a> </div>
<!-- *********************************************************************** -->
-
-LLVM supports the notion of an "intrinsic function". These functions have well
-known names and semantics, and are required to follow certain restrictions.
-Overall, these instructions represent an extension mechanism for the LLVM
-language that does not require changing all of the transformations in LLVM to
-add to the language (or the bytecode reader/writer, the parser, etc...).<p>
-
-Intrinsic function names must all start with an "<tt>llvm.</tt>" prefix, this
-prefix is reserved in LLVM for intrinsic names, thus functions may not be named
-this. Intrinsic functions must always be external functions: you cannot define
-the body of intrinsic functions. Intrinsic functions may only be used in call
-or invoke instructions: it is illegal to take the address of an intrinsic
-function. Additionally, because intrinsic functions are part of the LLVM
-language, it is required that they all be documented here if any are added.<p>
-
-Unless an intrinsic function is target-specific, there must be a lowering pass
-to eliminate the intrinsic or all backends must support the intrinsic
-function.<p>
-
-
+<div class="doc_text">
+<p>LLVM supports the notion of an "intrinsic function". These
+functions have well known names and semantics, and are required to
+follow certain restrictions. Overall, these instructions represent an
+extension mechanism for the LLVM language that does not require
+changing all of the transformations in LLVM to add to the language (or
+the bytecode reader/writer, the parser, etc...).</p>
+<p>Intrinsic function names must all start with an "<tt>llvm.</tt>"
+prefix, this prefix is reserved in LLVM for intrinsic names, thus
+functions may not be named this. Intrinsic functions must always be
+external functions: you cannot define the body of intrinsic functions.
+Intrinsic functions may only be used in call or invoke instructions: it
+is illegal to take the address of an intrinsic function. Additionally,
+because intrinsic functions are part of the LLVM language, it is
+required that they all be documented here if any are added.</p>
+<p>Unless an intrinsic function is target-specific, there must be a
+lowering pass to eliminate the intrinsic or all backends must support
+the intrinsic function.</p>
+</div>
<!-- ======================================================================= -->
-</ul><table width="100%" bgcolor="#441188" border=0 cellpadding=4 cellspacing=0>
-<tr><td> </td><td width="100%"> <font color="#EEEEFF" face="Georgia,Palatino"><b>
-<a name="int_varargs">Variable Argument Handling Intrinsics
-</b></font></td></tr></table><ul>
-
-Variable argument support is defined in LLVM with the <a
-href="#i_va_arg"><tt>va_arg</tt></a> instruction and these three intrinsic
-functions. These function correspond almost directly to the similarly named
-macros defined in the <tt><stdarg.h></tt> header file.<p>
-
-All of these functions operate on arguments that use a target-specific type
-"<tt>va_list</tt>". The LLVM assembly language reference manual does not define
-what this type is, so all transformations should be prepared to handle
-intrinsics with any type used.<p>
-
-This example shows how the <a href="#i_va_arg"><tt>va_arg</tt></a> instruction
-and the variable argument handling intrinsic functions are used.<p>
-
-<pre>
-int %test(int %X, ...) {
- ; Allocate two va_list items. On this target, va_list is of type sbyte*
- %ap = alloca sbyte*
- %aq = alloca sbyte*
-
- ; Initialize variable argument processing
- call void (sbyte**)* %<a href="#i_va_start">llvm.va_start</a>(sbyte** %ap)
-
- ; Read a single integer argument
- %tmp = <a href="#i_va_arg">va_arg</a> sbyte** %ap, int
-
- ; Demonstrate usage of llvm.va_copy and llvm_va_end
- %apv = load sbyte** %ap
- call void %<a href="#i_va_copy">llvm.va_copy</a>(sbyte** %aq, sbyte* %apv)
- call void %<a href="#i_va_end">llvm.va_end</a>(sbyte** %aq)
-
- ; Stop processing of arguments.
- call void %<a href="#i_va_end">llvm.va_end</a>(sbyte** %ap)
- ret int %tmp
-}
-</pre>
-
+<div class="doc_subsection"> <a name="int_varargs">Variable Argument
+Handling Intrinsics</a> </div>
+<div class="doc_text">
+<p>Variable argument support is defined in LLVM with the <a
+ href="#i_vanext"><tt>vanext</tt></a> instruction and these three
+intrinsic functions. These functions are related to the similarly
+named macros defined in the <tt><stdarg.h></tt> header file.</p>
+<p>All of these functions operate on arguments that use a
+target-specific value type "<tt>va_list</tt>". The LLVM assembly
+language reference manual does not define what this type is, so all
+transformations should be prepared to handle intrinsics with any type
+used.</p>
+<p>This example shows how the <a href="#i_vanext"><tt>vanext</tt></a>
+instruction and the variable argument handling intrinsic functions are
+used.</p>
+<pre>int %test(int %X, ...) {<br> ; Initialize variable argument processing<br> %ap = call sbyte*()* %<a
+ href="#i_va_start">llvm.va_start</a>()<br><br> ; Read a single integer argument<br> %tmp = vaarg sbyte* %ap, int<br><br> ; Advance to the next argument<br> %ap2 = vanext sbyte* %ap, int<br><br> ; Demonstrate usage of llvm.va_copy and llvm.va_end<br> %aq = call sbyte* (sbyte*)* %<a
+ href="#i_va_copy">llvm.va_copy</a>(sbyte* %ap2)<br> call void %<a
+ href="#i_va_end">llvm.va_end</a>(sbyte* %aq)<br><br> ; Stop processing of arguments.<br> call void %<a
+ href="#i_va_end">llvm.va_end</a>(sbyte* %ap2)<br> ret int %tmp<br>}<br></pre>
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_va_start"><h4><hr size=0>'<tt>llvm.va_start</tt>' Intrinsic</h4><ul>
-
+<div class="doc_subsubsection"> <a name="i_va_start">'<tt>llvm.va_start</tt>'
+Intrinsic</a> </div>
+<div class="doc_text">
<h5>Syntax:</h5>
-<pre>
- call void (va_list*)* %llvm.va_start(<va_list>* <arglist>)
-</pre>
-
+<pre> call va_list ()* %llvm.va_start()<br></pre>
<h5>Overview:</h5>
-
-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> and <tt><a
-href="#i_va_end">llvm.va_end</a></tt>, and must be called before either are
-invoked.<p>
-
-<h5>Arguments:</h5>
-
-The argument is a pointer to a <tt>va_list</tt> element to initialize.<p>
-
+<p>The '<tt>llvm.va_start</tt>' intrinsic returns a new <tt><arglist></tt>
+for subsequent use by the variable argument intrinsics.</p>
<h5>Semantics:</h5>
-
-The '<tt>llvm.va_start</tt>' intrinsic works just like the <tt>va_start</tt>
-macro available in C. In a target-dependent way, it initializes the
-<tt>va_list</tt> element the argument points to, so that the next call to
-<tt>va_arg</tt> will produce the first variable argument passed to the function.
-Unlike the C <tt>va_start</tt> macro, this intrinsic does not need to know the
-last argument of the function, the compiler can figure that out.<p>
-
-
+<p>The '<tt>llvm.va_start</tt>' intrinsic works just like the <tt>va_start</tt>
+macro available in C. In a target-dependent way, it initializes and
+returns a <tt>va_list</tt> element, so that the next <tt>vaarg</tt>
+will produce the first variable argument passed to the function. Unlike
+the C <tt>va_start</tt> macro, this intrinsic does not need to know the
+last argument of the function, the compiler can figure that out.</p>
+<p>Note that this intrinsic function is only legal to be called from
+within the body of a variable argument function.</p>
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_va_end"><h4><hr size=0>'<tt>llvm.va_end</tt>' Intrinsic</h4><ul>
-
+<div class="doc_subsubsection"> <a name="i_va_end">'<tt>llvm.va_end</tt>'
+Intrinsic</a> </div>
+<div class="doc_text">
<h5>Syntax:</h5>
-<pre>
- call void (va_list*)* %llvm.va_end(<va_list>* <arglist>)
-</pre>
-
+<pre> call void (va_list)* %llvm.va_end(va_list <arglist>)<br></pre>
<h5>Overview:</h5>
-
-The '<tt>llvm.va_end</tt>' intrinsic destroys <tt>*<arglist></tt> which
-has been initialized previously with <tt><a
-href="#i_va_begin">llvm.va_begin</a></tt>.<p>
-
+<p>The '<tt>llvm.va_end</tt>' intrinsic destroys <tt><arglist></tt>
+which has been initialized previously with <tt><a href="#i_va_start">llvm.va_start</a></tt>
+or <tt><a href="#i_va_copy">llvm.va_copy</a></tt>.</p>
<h5>Arguments:</h5>
-
-The argument is a pointer to a <tt>va_list</tt> element to destroy.<p>
-
+<p>The argument is a <tt>va_list</tt> to destroy.</p>
<h5>Semantics:</h5>
-
-The '<tt>llvm.va_end</tt>' intrinsic works just like the <tt>va_end</tt> macro
-available in C. In a target-dependent way, it destroys the <tt>va_list</tt>
-that the argument points to. Calls to <a
-href="#i_va_start"><tt>llvm.va_start</tt></a> and <a
-href="#i_va_copy"><tt>llvm.va_copy</tt></a> must be matched exactly with calls
-to <tt>llvm.va_end</tt>.<p>
-
-
-
+<p>The '<tt>llvm.va_end</tt>' intrinsic works just like the <tt>va_end</tt>
+macro available in C. In a target-dependent way, it destroys the <tt>va_list</tt>.
+Calls to <a href="#i_va_start"><tt>llvm.va_start</tt></a> and <a
+ href="#i_va_copy"><tt>llvm.va_copy</tt></a> must be matched exactly
+with calls to <tt>llvm.va_end</tt>.</p>
+</div>
<!-- _______________________________________________________________________ -->
-</ul><a name="i_va_copy"><h4><hr size=0>'<tt>llvm.va_copy</tt>' Intrinsic</h4><ul>
-
+<div class="doc_subsubsection"> <a name="i_va_copy">'<tt>llvm.va_copy</tt>'
+Intrinsic</a> </div>
+<div class="doc_text">
<h5>Syntax:</h5>
-<pre>
- call void (va_list*, va_list)* %va_copy(<va_list>* <destarglist>,
- <va_list> <srcarglist>)
-</pre>
-
+<pre> call va_list (va_list)* %llvm.va_copy(va_list <destarglist>)<br></pre>
<h5>Overview:</h5>
-
-The '<tt>llvm.va_copy</tt>' intrinsic copies the current argument position from
-the source argument list to the destination argument list.<p>
-
+<p>The '<tt>llvm.va_copy</tt>' intrinsic copies the current argument
+position from the source argument list to the destination argument list.</p>
<h5>Arguments:</h5>
-
-The first argument is a pointer to a <tt>va_list</tt> element to initialize.
-The second argument is a <tt>va_list</tt> element to copy from.<p>
-
-
+<p>The argument is the <tt>va_list</tt> to copy.</p>
<h5>Semantics:</h5>
-
-The '<tt>llvm.va_copy</tt>' intrinsic works just like the <tt>va_copy</tt> macro
-available in C. In a target-dependent way, it copies the source
-<tt>va_list</tt> element into the destination list. This intrinsic is necessary
-because the <tt><a href="i_va_begin">llvm.va_begin</a></tt> intrinsic may be
-arbitrarily complex and require memory allocation, for example.<p>
-
-
-<!-- *********************************************************************** -->
-</ul>
+<p>The '<tt>llvm.va_copy</tt>' intrinsic works just like the <tt>va_copy</tt>
+macro available in C. In a target-dependent way, it copies the source <tt>va_list</tt>
+element into the returned list. This intrinsic is necessary because the <tt><a
+ href="i_va_start">llvm.va_start</a></tt> intrinsic may be arbitrarily
+complex and require memory allocation, for example.</p>
+</div>
<!-- *********************************************************************** -->
-
-
<hr>
-<font size=-1>
+<div class="doc_footer">
<address><a href="mailto:sabre@nondot.org">Chris Lattner</a></address>
-<!-- Created: Tue Jan 23 15:19:28 CST 2001 -->
-<!-- hhmts start -->
-Last modified: Wed Jun 18 16:29:55 CDT 2003
-<!-- hhmts end -->
-</font>
-</body></html>
+<a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a> <br>
+Last modified: $Date$ </div>
+</body>
+</html>