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| author | Gordon Henriksen <gordonhenriksen@mac.com> | 2007-11-04 18:10:18 +0000 |
|---|---|---|
| committer | Gordon Henriksen <gordonhenriksen@mac.com> | 2007-11-04 18:10:18 +0000 |
| commit | 75ff18ed2b43439c76d449f7cc14776308bb85ea (patch) | |
| tree | d9496931345a52623015cc3e69444bc8e7a8f28f /docs/Passes.html | |
| parent | f4c164c2b5bbaa2be4f1d8fedcf9df621378340d (diff) | |
| download | external_llvm-75ff18ed2b43439c76d449f7cc14776308bb85ea.zip external_llvm-75ff18ed2b43439c76d449f7cc14776308bb85ea.tar.gz external_llvm-75ff18ed2b43439c76d449f7cc14776308bb85ea.tar.bz2 | |
Completing Passes.html with the exception of -emitbitcode, which should be
removed. This document could still stand for significant improvement:
* Editing the pass descriptions; most were lifted with minimal editing from
comments. Although implementation details were elided, many of the were not
written for the audience that would be interested in this document.
* More "before and after" examples.
* More implicit dependency details. (Perhaps listing transforms in
-std-compile-opts order would help alleviate this.)
* Adding documentation for how to invoke passes programmatically.
* Rearranging the document into a more logical taxonomy. For instance, putting
profiling passes together.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@43677 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'docs/Passes.html')
| -rw-r--r-- | docs/Passes.html | 63 |
1 files changed, 58 insertions, 5 deletions
diff --git a/docs/Passes.html b/docs/Passes.html index b8d5fa1..352263e 100644 --- a/docs/Passes.html +++ b/docs/Passes.html @@ -1808,7 +1808,10 @@ if (i == j) <a name="deadarghaX0r">Dead Argument Hacking (BUGPOINT USE ONLY; DO NOT USE)</a> </div> <div class="doc_text"> - <p>Yet to be written.</p> + <p> + Same as dead argument elimination, but deletes arguments to functions which + are external. This is only for use by <a + href="Bugpoint.html">bugpoint</a>.</p> </div> <!-------------------------------------------------------------------------- --> @@ -1816,7 +1819,9 @@ if (i == j) <a name="extract-blocks">Extract Basic Blocks From Module (for bugpoint use)</a> </div> <div class="doc_text"> - <p>Yet to be written.</p> + <p> + This pass is used by bugpoint to extract all blocks from the module into their + own functions.</p> </div> <!-------------------------------------------------------------------------- --> @@ -1832,7 +1837,50 @@ if (i == j) <a name="verify">Module Verifier</a> </div> <div class="doc_text"> - <p>Yet to be written.</p> + <p> + Verifies an LLVM IR code. This is useful to run after an optimization which is + undergoing testing. Note that <tt>llvm-as</tt> verifies its input before + emitting bitcode, and also that malformed bitcode is likely to make LLVM + crash. All language front-ends are therefore encouraged to verify their output + before performing optimizing transformations. + </p> + + <p> + <li>Both of a binary operator's parameters are of the same type.</li> + <li>Verify that the indices of mem access instructions match other + operands.</li> + <li>Verify that arithmetic and other things are only performed on + first-class types. Verify that shifts and logicals only happen on + integrals f.e.</li> + <li>All of the constants in a switch statement are of the correct type.</li> + <li>The code is in valid SSA form.</li> + <li>It should be illegal to put a label into any other type (like a + structure) or to return one. [except constant arrays!]</li> + <li>Only phi nodes can be self referential: 'add int %0, %0 ; <int>:0' is + bad.</li> + <li>PHI nodes must have an entry for each predecessor, with no extras.</li> + <li>PHI nodes must be the first thing in a basic block, all grouped + together.</li> + <li>PHI nodes must have at least one entry.</li> + <li>All basic blocks should only end with terminator insts, not contain + them.</li> + <li>The entry node to a function must not have predecessors.</li> + <li>All Instructions must be embedded into a basic block.</li> + <li>Functions cannot take a void-typed parameter.</li> + <li>Verify that a function's argument list agrees with its declared + type.</li> + <li>It is illegal to specify a name for a void value.</li> + <li>It is illegal to have a internal global value with no initializer.</li> + <li>It is illegal to have a ret instruction that returns a value that does + not agree with the function return value type.</li> + <li>Function call argument types match the function prototype.</li> + <li>All other things that are tested by asserts spread about the code.</li> + </p> + + <p> + Note that this does not provide full security verification (like Java), but + instead just tries to ensure that code is well-formed. + </p> </div> <!-------------------------------------------------------------------------- --> @@ -1840,7 +1888,9 @@ if (i == j) <a name="view-cfg">View CFG of function</a> </div> <div class="doc_text"> - <p>Yet to be written.</p> + <p> + Displays the control flow graph using the GraphViz tool. + </p> </div> <!-------------------------------------------------------------------------- --> @@ -1848,7 +1898,10 @@ if (i == j) <a name="view-cfg-only">View CFG of function (with no function bodies)</a> </div> <div class="doc_text"> - <p>Yet to be written.</p> + <p> + Displays the control flow graph using the GraphViz tool, but omitting function + bodies. + </p> </div> <!-- *********************************************************************** --> |