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Passes.html now 'passes' validation.

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llvm-svn: 43335
This commit is contained in:
Gordon Henriksen 2007-10-25 08:58:56 +00:00
parent f95443425b
commit 2fe2889448
1 changed files with 21 additions and 19 deletions
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40
docs/Passes.html
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@ -4,6 +4,7 @@
<head>
<title>LLVM's Analysis and Transform Passes</title>
<link rel="stylesheet" href="llvm.css" type="text/css">
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
</head>
<body>
@ -20,7 +21,7 @@ while (<HTML>) {
m:^<tr><td><a href="#(.*)">-.*</a></td><td>.*</td></tr>$: or next;
$order{$1} = sprintf("%03d", 1 + int %order);
}
open HELP, "../Release/bin/opt --help|" or die "open: opt --help: $!\n";
open HELP, "../Release/bin/opt -help|" or die "open: opt -help: $!\n";
while (<HELP>) {
m:^ -([^ ]+) +- (.*)$: or next;
my $o = $order{$1};
@ -66,8 +67,8 @@ EOT
</div>
<div class="doc_text" >
<table>
<tr><th colspan="3"><b>ANALYSIS PASSES</b></th></tr>
<tr><th>Option</th><th>Name</th><th>Directory</th></tr>
<tr><th colspan="2"><b>ANALYSIS PASSES</b></th></tr>
<tr><th>Option</th><th>Name</th></tr>
<tr><td><a href="#aa-eval">-aa-eval</a></td><td>Exhaustive Alias Analysis Precision Evaluator</td></tr>
<tr><td><a href="#anders-aa">-anders-aa</a></td><td>Andersen's Interprocedural Alias Analysis</td></tr>
<tr><td><a href="#basicaa">-basicaa</a></td><td>Basic Alias Analysis (default AA impl)</td></tr>
@ -105,8 +106,8 @@ EOT
<tr><td><a href="#targetdata">-targetdata</a></td><td>Target Data Layout</td></tr>
<tr><th colspan="3"><b>TRANSFORM PASSES</b></th></tr>
<tr><th>Option</th><th>Name</th><th>Directory</th></tr>
<tr><th colspan="2"><b>TRANSFORM PASSES</b></th></tr>
<tr><th>Option</th><th>Name</th></tr>
<tr><td><a href="#adce">-adce</a></td><td>Aggressive Dead Code Elimination</td></tr>
<tr><td><a href="#argpromotion">-argpromotion</a></td><td>Promote 'by reference' arguments to scalars</td></tr>
<tr><td><a href="#block-placement">-block-placement</a></td><td>Profile Guided Basic Block Placement</td></tr>
@ -169,8 +170,8 @@ EOT
<tr><td><a href="#tailduplicate">-tailduplicate</a></td><td>Tail Duplication</td></tr>
<tr><th colspan="3"><b>UTILITY PASSES</b></th></tr>
<tr><th>Option</th><th>Name</th><th>Directory</th></tr>
<tr><th colspan="2"><b>UTILITY PASSES</b></th></tr>
<tr><th>Option</th><th>Name</th></tr>
<tr><td><a href="#deadarghaX0r">-deadarghaX0r</a></td><td>Dead Argument Hacking (BUGPOINT USE ONLY; DO NOT USE)</td></tr>
<tr><td><a href="#extract-blocks">-extract-blocks</a></td><td>Extract Basic Blocks From Module (for bugpoint use)</td></tr>
<tr><td><a href="#emitbitcode">-emitbitcode</a></td><td>Bitcode Writer</td></tr>
@ -529,15 +530,16 @@ EOT
<p>Correlated Expression Elimination propagates information from conditional
branches to blocks dominated by destinations of the branch. It propagates
information from the condition check itself into the body of the branch,
allowing transformations like these for example:
<pre>
if (i == 7)
... 4*i; // constant propagation
allowing transformations like these for example:</p>
<blockquote><pre>
if (i == 7)
... 4*i; // constant propagation
M = i+1; N = j+1;
if (i == j)
X = M-N; // = M-M == 0;
</pre></p>
M = i+1; N = j+1;
if (i == j)
X = M-N; // = M-M == 0;
</pre></blockquote>
<p>This is called Correlated Expression Elimination because we eliminate or
simplify expressions that are correlated with the direction of a branch. In
@ -569,10 +571,10 @@ EOT
<div class="doc_text">
<p>This file implements constant propagation and merging. It looks for
instructions involving only constant operands and replaces them with a
constant value instead of an instruction. For example:
<pre>add i32 1, 2</pre><br/>
becomes
<pre>i32 3</pre></p>
constant value instead of an instruction. For example:</p>
<blockquote><pre>add i32 1, 2</pre></blockquote>
<p>becomes</p>
<blockquote><pre>i32 3</pre></blockquote>
<p>NOTE: this pass has a habit of making definitions be dead. It is a good
idea to to run a <a href="#die">DIE</a> (Dead Instruction Elimination) pass
sometime after running this pass.</p>