<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="#basicaa">-basicaa</a></td><td>Basic Alias Analysis (default AA impl)</td></tr>
+<tr><td><a href="#basicaa">-basicaa</a></td><td>Basic Alias Analysis (stateless AA impl)</td></tr>
<tr><td><a href="#basiccg">-basiccg</a></td><td>Basic CallGraph Construction</td></tr>
-<tr><td><a href="#codegenprepare">-codegenprepare</a></td><td>Optimize for code generation</td></tr>
<tr><td><a href="#count-aa">-count-aa</a></td><td>Count Alias Analysis Query Responses</td></tr>
<tr><td><a href="#debug-aa">-debug-aa</a></td><td>AA use debugger</td></tr>
<tr><td><a href="#domfrontier">-domfrontier</a></td><td>Dominance Frontier Construction</td></tr>
<tr><td><a href="#dot-callgraph">-dot-callgraph</a></td><td>Print Call Graph to 'dot' file</td></tr>
<tr><td><a href="#dot-cfg">-dot-cfg</a></td><td>Print CFG of function to 'dot' file</td></tr>
<tr><td><a href="#dot-cfg-only">-dot-cfg-only</a></td><td>Print CFG of function to 'dot' file (with no function bodies)</td></tr>
-<tr><td><a href="#dot-dom">-dot-dom</a></td><td>Print dominator tree of function to 'dot' file</td></tr>
-<tr><td><a href="#dot-dom-only">-dot-dom-only</a></td><td>Print dominator tree of function to 'dot' file (with no function bodies)</td></tr>
-<tr><td><a href="#dot-postdom">-dot-postdom</a></td><td>Print post dominator tree of function to 'dot' file</td></tr>
-<tr><td><a href="#dot-postdom-only">-dot-postdom-only</a></td><td>Print post dominator tree of function to 'dot' file (with no function bodies)</td></tr>
+<tr><td><a href="#dot-dom">-dot-dom</a></td><td>Print dominance tree of function to 'dot' file</td></tr>
+<tr><td><a href="#dot-dom-only">-dot-dom-only</a></td><td>Print dominance tree of function to 'dot' file (with no function bodies)</td></tr>
+<tr><td><a href="#dot-postdom">-dot-postdom</a></td><td>Print postdominance tree of function to 'dot' file</td></tr>
+<tr><td><a href="#dot-postdom-only">-dot-postdom-only</a></td><td>Print postdominance tree of function to 'dot' file (with no function bodies)</td></tr>
<tr><td><a href="#globalsmodref-aa">-globalsmodref-aa</a></td><td>Simple mod/ref analysis for globals</td></tr>
<tr><td><a href="#instcount">-instcount</a></td><td>Counts the various types of Instructions</td></tr>
-<tr><td><a href="#interprocedural-aa-eval">-interprocedural-aa-eval</a></td><td>Exhaustive Interprocedural Alias Analysis Precision Evaluator</td></tr>
-<tr><td><a href="#interprocedural-basic-aa">-interprocedural-basic-aa</a></td><td>Interprocedural Basic Alias Analysis</td></tr>
<tr><td><a href="#intervals">-intervals</a></td><td>Interval Partition Construction</td></tr>
<tr><td><a href="#iv-users">-iv-users</a></td><td>Induction Variable Users</td></tr>
<tr><td><a href="#lazy-value-info">-lazy-value-info</a></td><td>Lazy Value Information Analysis</td></tr>
<tr><td><a href="#lda">-lda</a></td><td>Loop Dependence Analysis</td></tr>
<tr><td><a href="#libcall-aa">-libcall-aa</a></td><td>LibCall Alias Analysis</td></tr>
-<tr><td><a href="#lint">-lint</a></td><td>Check for common errors in LLVM IR</td></tr>
-<tr><td><a href="#live-values">-live-values</a></td><td>Value Liveness Analysis</td></tr>
+<tr><td><a href="#lint">-lint</a></td><td>Statically lint-checks LLVM IR</td></tr>
<tr><td><a href="#loops">-loops</a></td><td>Natural Loop Information</td></tr>
<tr><td><a href="#memdep">-memdep</a></td><td>Memory Dependence Analysis</td></tr>
-<tr><td><a href="#module-debuginfo">-module-debuginfo</a></td><td>Prints module debug info metadata</td></tr>
+<tr><td><a href="#module-debuginfo">-module-debuginfo</a></td><td>Decodes module-level debug info</td></tr>
<tr><td><a href="#no-aa">-no-aa</a></td><td>No Alias Analysis (always returns 'may' alias)</td></tr>
<tr><td><a href="#no-profile">-no-profile</a></td><td>No Profile Information</td></tr>
-<tr><td><a href="#pointertracking">-pointertracking</a></td><td>Track pointer bounds</td></tr>
<tr><td><a href="#postdomfrontier">-postdomfrontier</a></td><td>Post-Dominance Frontier Construction</td></tr>
<tr><td><a href="#postdomtree">-postdomtree</a></td><td>Post-Dominator Tree Construction</td></tr>
<tr><td><a href="#print-alias-sets">-print-alias-sets</a></td><td>Alias Set Printer</td></tr>
<tr><td><a href="#print-used-types">-print-used-types</a></td><td>Find Used Types</td></tr>
<tr><td><a href="#profile-estimator">-profile-estimator</a></td><td>Estimate profiling information</td></tr>
<tr><td><a href="#profile-loader">-profile-loader</a></td><td>Load profile information from llvmprof.out</td></tr>
-<tr><td><a href="#regions">-regions</a></td><td>Detect single entry single exit regions in a function</td></tr>
<tr><td><a href="#profile-verifier">-profile-verifier</a></td><td>Verify profiling information</td></tr>
+<tr><td><a href="#regions">-regions</a></td><td>Detect single entry single exit regions</td></tr>
<tr><td><a href="#scalar-evolution">-scalar-evolution</a></td><td>Scalar Evolution Analysis</td></tr>
<tr><td><a href="#scev-aa">-scev-aa</a></td><td>ScalarEvolution-based Alias Analysis</td></tr>
<tr><td><a href="#targetdata">-targetdata</a></td><td>Target Data Layout</td></tr>
<tr><th colspan="2"><b>TRANSFORM PASSES</b></th></tr>
<tr><th>Option</th><th>Name</th></tr>
-<tr><td><a href="#abcd">-abcd</a></td><td>Remove redundant conditional branches</td></tr>
<tr><td><a href="#adce">-adce</a></td><td>Aggressive Dead Code Elimination</td></tr>
<tr><td><a href="#always-inline">-always-inline</a></td><td>Inliner for always_inline functions</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>
<tr><td><a href="#break-crit-edges">-break-crit-edges</a></td><td>Break critical edges in CFG</td></tr>
-<tr><td><a href="#codegenprepare">-codegenprepare</a></td><td>Prepare a function for code generation </td></tr>
+<tr><td><a href="#codegenprepare">-codegenprepare</a></td><td>Optimize for code generation</td></tr>
<tr><td><a href="#constmerge">-constmerge</a></td><td>Merge Duplicate Global Constants</td></tr>
<tr><td><a href="#constprop">-constprop</a></td><td>Simple constant propagation</td></tr>
<tr><td><a href="#dce">-dce</a></td><td>Dead Code Elimination</td></tr>
<tr><td><a href="#internalize">-internalize</a></td><td>Internalize Global Symbols</td></tr>
<tr><td><a href="#ipconstprop">-ipconstprop</a></td><td>Interprocedural constant propagation</td></tr>
<tr><td><a href="#ipsccp">-ipsccp</a></td><td>Interprocedural Sparse Conditional Constant Propagation</td></tr>
-<tr><td><a href="#jump-threading">-jump-threading</a></td><td>Thread control through conditional blocks </td></tr>
+<tr><td><a href="#jump-threading">-jump-threading</a></td><td>Jump Threading</td></tr>
<tr><td><a href="#lcssa">-lcssa</a></td><td>Loop-Closed SSA Form Pass</td></tr>
<tr><td><a href="#licm">-licm</a></td><td>Loop Invariant Code Motion</td></tr>
-<tr><td><a href="#loop-deletion">-loop-deletion</a></td><td>Dead Loop Deletion Pass </td></tr>
+<tr><td><a href="#loop-deletion">-loop-deletion</a></td><td>Delete dead loops</td></tr>
<tr><td><a href="#loop-extract">-loop-extract</a></td><td>Extract loops into new functions</td></tr>
<tr><td><a href="#loop-extract-single">-loop-extract-single</a></td><td>Extract at most one loop into a new function</td></tr>
-<tr><td><a href="#loop-index-split">-loop-index-split</a></td><td>Index Split Loops</td></tr>
<tr><td><a href="#loop-reduce">-loop-reduce</a></td><td>Loop Strength Reduction</td></tr>
<tr><td><a href="#loop-rotate">-loop-rotate</a></td><td>Rotate Loops</td></tr>
+<tr><td><a href="#loop-simplify">-loop-simplify</a></td><td>Canonicalize natural loops</td></tr>
<tr><td><a href="#loop-unroll">-loop-unroll</a></td><td>Unroll loops</td></tr>
<tr><td><a href="#loop-unswitch">-loop-unswitch</a></td><td>Unswitch loops</td></tr>
-<tr><td><a href="#loopsimplify">-loopsimplify</a></td><td>Canonicalize natural loops</td></tr>
+<tr><td><a href="#loweratomic">-loweratomic</a></td><td>Lower atomic intrinsics to non-atomic form</td></tr>
<tr><td><a href="#lowerinvoke">-lowerinvoke</a></td><td>Lower invoke and unwind, for unwindless code generators</td></tr>
<tr><td><a href="#lowersetjmp">-lowersetjmp</a></td><td>Lower Set Jump</td></tr>
<tr><td><a href="#lowerswitch">-lowerswitch</a></td><td>Lower SwitchInst's to branches</td></tr>
<tr><td><a href="#mem2reg">-mem2reg</a></td><td>Promote Memory to Register</td></tr>
-<tr><td><a href="#memcpyopt">-memcpyopt</a></td><td>Optimize use of memcpy and friends</td></tr>
+<tr><td><a href="#memcpyopt">-memcpyopt</a></td><td>MemCpy Optimization</td></tr>
<tr><td><a href="#mergefunc">-mergefunc</a></td><td>Merge Functions</td></tr>
<tr><td><a href="#mergereturn">-mergereturn</a></td><td>Unify function exit nodes</td></tr>
<tr><td><a href="#partial-inliner">-partial-inliner</a></td><td>Partial Inliner</td></tr>
-<tr><td><a href="#partialspecialization">-partialspecialization</a></td><td>Partial Specialization</td></tr>
<tr><td><a href="#prune-eh">-prune-eh</a></td><td>Remove unused exception handling info</td></tr>
<tr><td><a href="#reassociate">-reassociate</a></td><td>Reassociate expressions</td></tr>
<tr><td><a href="#reg2mem">-reg2mem</a></td><td>Demote all values to stack slots</td></tr>
-<tr><td><a href="#scalarrepl">-scalarrepl</a></td><td>Scalar Replacement of Aggregates</td></tr>
+<tr><td><a href="#scalarrepl">-scalarrepl</a></td><td>Scalar Replacement of Aggregates (DT)</td></tr>
<tr><td><a href="#sccp">-sccp</a></td><td>Sparse Conditional Constant Propagation</td></tr>
-<tr><td><a href="#sink">-sink</a></td><td>Code Sinking</td></tr>
<tr><td><a href="#simplify-libcalls">-simplify-libcalls</a></td><td>Simplify well-known library calls</td></tr>
-<tr><td><a href="#simplify-libcalls-halfpowr">-simplify-libcalls-halfpowr</a></td><td>Simplify half_powr library calls</td></tr>
<tr><td><a href="#simplifycfg">-simplifycfg</a></td><td>Simplify the CFG</td></tr>
-<tr><td><a href="#split-geps">-split-geps</a></td><td>Split complex GEPs into simple GEPs</td></tr>
-<tr><td><a href="#ssi">-ssi</a></td><td>Static Single Information Construction</td></tr>
-<tr><td><a href="#ssi-everything">-ssi-everything</a></td><td>Static Single Information Construction (everything, intended for debugging)</td></tr>
+<tr><td><a href="#sink">-sink</a></td><td>Code sinking</td></tr>
+<tr><td><a href="#sretpromotion">-sretpromotion</a></td><td>Promote sret arguments to multiple ret values</td></tr>
<tr><td><a href="#strip">-strip</a></td><td>Strip all symbols from a module</td></tr>
<tr><td><a href="#strip-dead-debug-info">-strip-dead-debug-info</a></td><td>Strip debug info for unused symbols</td></tr>
-<tr><td><a href="#strip-dead-prototypes">-strip-dead-prototypes</a></td><td>Remove unused function declarations</td></tr>
+<tr><td><a href="#strip-dead-prototypes">-strip-dead-prototypes</a></td><td>Strip Unused Function Prototypes</td></tr>
<tr><td><a href="#strip-debug-declare">-strip-debug-declare</a></td><td>Strip all llvm.dbg.declare intrinsics</td></tr>
<tr><td><a href="#strip-nondebug">-strip-nondebug</a></td><td>Strip all symbols, except dbg symbols, from a module</td></tr>
-<tr><td><a href="#sretpromotion">-sretpromotion</a></td><td>Promote sret arguments</td></tr>
<tr><td><a href="#tailcallelim">-tailcallelim</a></td><td>Tail Call Elimination</td></tr>
<tr><td><a href="#tailduplicate">-tailduplicate</a></td><td>Tail Duplication</td></tr>
<tr><td><a href="#verify">-verify</a></td><td>Module Verifier</td></tr>
<tr><td><a href="#view-cfg">-view-cfg</a></td><td>View CFG of function</td></tr>
<tr><td><a href="#view-cfg-only">-view-cfg-only</a></td><td>View CFG of function (with no function bodies)</td></tr>
-<tr><td><a href="#view-dom">-view-dom</a></td><td>View dominator tree of function</td></tr>
-<tr><td><a href="#view-dom-only">-view-dom-only</a></td><td>View dominator tree of function (with no function bodies)</td></tr>
-<tr><td><a href="#view-postdom">-view-postdom</a></td><td>View post dominator tree of function</td></tr>
-<tr><td><a href="#view-postdom-only">-view-postdom-only</a></td><td>View post dominator tree of function (with no function bodies)</td></tr>
+<tr><td><a href="#view-dom">-view-dom</a></td><td>View dominance tree of function</td></tr>
+<tr><td><a href="#view-dom-only">-view-dom-only</a></td><td>View dominance tree of function (with no function bodies)</td></tr>
+<tr><td><a href="#view-postdom">-view-postdom</a></td><td>View postdominance tree of function</td></tr>
+<tr><td><a href="#view-postdom-only">-view-postdom-only</a></td><td>View postdominance tree of function (with no function bodies)</td></tr>
</table>
</div>
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
- <a name="basicaa">-basicaa: Basic Alias Analysis (default AA impl)</a>
+ <a name="basicaa">-basicaa: Basic Alias Analysis (stateless AA impl)</a>
</div>
<div class="doc_text">
<p>
<p>Yet to be written.</p>
</div>
-<!-------------------------------------------------------------------------- -->
-<div class="doc_subsection">
- <a name="codegenprepare">-codegenprepare: Optimize for code generation</a>
-</div>
-<div class="doc_text">
- <p>
- This pass munges the code in the input function to better prepare it for
- SelectionDAG-based code generation. This works around limitations in it's
- basic-block-at-a-time approach. It should eventually be removed.
- </p>
-</div>
-
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
<a name="count-aa">-count-aa: Count Alias Analysis Query Responses</a>
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
- <a name="dot-dom">-dot-dom: Print dominator tree of function to 'dot' file</a>
+ <a name="dot-dom">-dot-dom: Print dominance tree of function to 'dot' file</a>
</div>
<div class="doc_text">
<p>
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
- <a name="dot-dom-only">-dot-dom-only: Print dominator tree of function to 'dot' file (with no
- function bodies)</a>
+ <a name="dot-dom-only">-dot-dom-only: Print dominance tree of function to 'dot' file (with no function bodies)</a>
</div>
<div class="doc_text">
<p>
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
- <a name="dot-postdom">dot-postdom: Print post dominator tree of function to 'dot' file</a>
+ <a name="dot-postdom">-dot-postdom: Print postdominance tree of function to 'dot' file</a>
</div>
<div class="doc_text">
<p>
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
- <a name="dot-postdom-only">dot-postdom-only: Print post dominator tree of function to 'dot' file
- (with no function bodies)</a>
+ <a name="dot-postdom-only">-dot-postdom-only: Print postdominance tree of function to 'dot' file (with no function bodies)</a>
</div>
<div class="doc_text">
<p>
</p>
</div>
-<!-------------------------------------------------------------------------- -->
-<div class="doc_subsection">
- <a name="interprocedural-aa-eval">-interprocedural-aa-eval: Exhaustive Interprocedural Alias Analysis Precision Evaluator</a>
-</div>
-<div class="doc_text">
- <p>This pass implements a simple N^2 alias analysis accuracy evaluator.
- Basically, for each function in the program, it simply queries to see how the
- alias analysis implementation answers alias queries between each pair of
- pointers in the function.
- </p>
-</div>
-
-<!-------------------------------------------------------------------------- -->
-<div class="doc_subsection">
- <a name="interprocedural-basic-aa">-interprocedural-basic-aa: Interprocedural Basic Alias Analysis</a>
-</div>
-<div class="doc_text">
- <p>This pass defines the default implementation of the Alias Analysis interface
- that simply implements a few identities (two different globals cannot alias,
- etc), but otherwise does no analysis.
- </p>
-</div>
-
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
<a name="intervals">-intervals: Interval Partition Construction</a>
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
- <a name="lint">-lint: Check for common errors in LLVM IR</a>
+ <a name="lint">-lint: Statically lint-checks LLVM IR</a>
</div>
<div class="doc_text">
<p>This pass statically checks for common and easily-identified constructs
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
- <a name="live-values">-live-values: Values Liveness Analysis</a>
-</div>
-<div class="doc_text">
- <p>LLVM IR Value liveness analysis pass.</p>
-</div>
-
-<!-------------------------------------------------------------------------- -->
-<div class="doc_subsection">
- <a name="loops">-loops: Natural Loop Construction</a>
+ <a name="loops">-loops: Natural Loop Information</a>
</div>
<div class="doc_text">
<p>
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
- <a name="module-debuginfo">-module-debuginfo: Prints module debug info metadata</a>
+ <a name="module-debuginfo">-module-debuginfo: Decodes module-level debug info</a>
</div>
<div class="doc_text">
<p>This pass decodes the debug info metadata in a module and prints in a
</p>
</div>
-<!-------------------------------------------------------------------------- -->
-<div class="doc_subsection">
- <a name="pointertracking">-pointertracking: Track pointer bounds.</a>
-</div>
-<div class="doc_text">
- <p>Tracking of pointer bounds.
- </p>
-</div>
-
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
<a name="postdomfrontier">-postdomfrontier: Post-Dominance Frontier Construction</a>
<div class="doc_text">
<p>
This pass, only available in <code>opt</code>, prints the call graph to
- standard output in a human-readable form.
+ standard error in a human-readable form.
</p>
</div>
<div class="doc_text">
<p>
This pass, only available in <code>opt</code>, prints the SCCs of the call
- graph to standard output in a human-readable form.
+ graph to standard error in a human-readable form.
</p>
</div>
<div class="doc_text">
<p>
This pass, only available in <code>opt</code>, prints the SCCs of each
- function CFG to standard output in a human-readable form.
+ function CFG to standard error in a human-readable form.
</p>
</div>
<a name="print-dbginfo">-print-dbginfo: Print debug info in human readable form</a>
</div>
<div class="doc_text">
- <p>Pass that prints instructions, and associated debug info:
+ <p>Pass that prints instructions, and associated debug info:</p>
<ul>
<li>source/line/col information</li>
<li>original variable name</li>
<li>original type name</li>
</ul>
-
- </p>
</div>
<!-------------------------------------------------------------------------- -->
<p>Pass that checks profiling information for plausibility.</p>
</div>
<div class="doc_subsection">
- <a name="regions">-regions: Detect single entry single exit regions in a function</a>
+ <a name="regions">-regions: Detect single entry single exit regions</a>
</div>
<div class="doc_text">
<p>
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
- <a name="scev-aa">-scev-aa: </a>
+ <a name="scev-aa">-scev-aa: ScalarEvolution-based Alias Analysis</a>
</div>
<div class="doc_text">
<p>Simple alias analysis implemented in terms of ScalarEvolution queries.
</p>
</div>
-<!-------------------------------------------------------------------------- -->
-<div class="doc_subsection">
- <a name="strip-dead-debug-info">-strip-dead-debug-info: Strip debug info for unused symbols</a>
-</div>
-<div class="doc_text">
- <p>
- performs code stripping. this transformation can delete:
- </p>
-
- <ol>
- <li>names for virtual registers</li>
- <li>symbols for internal globals and functions</li>
- <li>debug information</li>
- </ol>
-
- <p>
- note that this transformation makes code much less readable, so it should
- only be used in situations where the <tt>strip</tt> utility would be used,
- such as reducing code size or making it harder to reverse engineer code.
- </p>
-</div>
-
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
<a name="targetdata">-targetdata: Target Data Layout</a>
<p>This section describes the LLVM Transform Passes.</p>
</div>
-<!-------------------------------------------------------------------------- -->
-<div class="doc_subsection">
- <a name="abcd">-abcd: Remove redundant conditional branches</a>
-</div>
-<div class="doc_text">
- <p>ABCD removes conditional branch instructions that can be proved redundant.
- With the SSI representation, each variable has a constraint. By analyzing these
- constraints we can prove that a branch is redundant. When a branch is proved
- redundant it means that one direction will always be taken; thus, we can change
- this branch into an unconditional jump.</p>
- <p>It is advisable to run <a href="#simplifycfg">SimplifyCFG</a> and
- <a href="#adce">Aggressive Dead Code Elimination</a> after ABCD
- to clean up the code.</p>
-</div>
-
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
<a name="adce">-adce: Aggressive Dead Code Elimination</a>
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
- <a name="codegenprepare">-codegenprepare: Prepare a function for code generation</a>
+ <a name="codegenprepare">-codegenprepare: Optimize for code generation</a>
</div>
<div class="doc_text">
This pass munges the code in the input function to better prepare it for
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
- <a name="jump-threading">-jump-threading: Thread control through conditional blocks</a>
+ <a name="jump-threading">-jump-threading: Jump Threading</a>
</div>
<div class="doc_text">
<p>
variable.</li>
</ul>
</div>
+
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
- <a name="loop-deletion">-loop-deletion: Dead Loop Deletion Pass</a>
+ <a name="loop-deletion">-loop-deletion: Delete dead loops</a>
</div>
<div class="doc_text">
<p>
</p>
</div>
-<!-------------------------------------------------------------------------- -->
-<div class="doc_subsection">
- <a name="loop-index-split">-loop-index-split: Index Split Loops</a>
-</div>
-<div class="doc_text">
- <p>
- This pass divides loop's iteration range by spliting loop such that each
- individual loop is executed efficiently.
- </p>
-</div>
-
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
<a name="loop-reduce">-loop-reduce: Loop Strength Reduction</a>
<p>A simple loop rotation transformation.</p>
</div>
+<!-------------------------------------------------------------------------- -->
+<div class="doc_subsection">
+ <a name="loop-simplify">-loop-simplify: Canonicalize natural loops</a>
+</div>
+<div class="doc_text">
+ <p>
+ This pass performs several transformations to transform natural loops into a
+ simpler form, which makes subsequent analyses and transformations simpler and
+ more effective.
+ </p>
+
+ <p>
+ Loop pre-header insertion guarantees that there is a single, non-critical
+ entry edge from outside of the loop to the loop header. This simplifies a
+ number of analyses and transformations, such as LICM.
+ </p>
+
+ <p>
+ Loop exit-block insertion guarantees that all exit blocks from the loop
+ (blocks which are outside of the loop that have predecessors inside of the
+ loop) only have predecessors from inside of the loop (and are thus dominated
+ by the loop header). This simplifies transformations such as store-sinking
+ that are built into LICM.
+ </p>
+
+ <p>
+ This pass also guarantees that loops will have exactly one backedge.
+ </p>
+
+ <p>
+ Note that the simplifycfg pass will clean up blocks which are split out but
+ end up being unnecessary, so usage of this pass should not pessimize
+ generated code.
+ </p>
+
+ <p>
+ This pass obviously modifies the CFG, but updates loop information and
+ dominator information.
+ </p>
+</div>
+
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
<a name="loop-unroll">-loop-unroll: Unroll loops</a>
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
- <a name="loopsimplify">-loopsimplify: Canonicalize natural loops</a>
+ <a name="loweratomic">-loweratomic: Lower atomic intrinsics to non-atomic form</a>
</div>
<div class="doc_text">
<p>
- This pass performs several transformations to transform natural loops into a
- simpler form, which makes subsequent analyses and transformations simpler and
- more effective.
- </p>
-
- <p>
- Loop pre-header insertion guarantees that there is a single, non-critical
- entry edge from outside of the loop to the loop header. This simplifies a
- number of analyses and transformations, such as LICM.
- </p>
-
- <p>
- Loop exit-block insertion guarantees that all exit blocks from the loop
- (blocks which are outside of the loop that have predecessors inside of the
- loop) only have predecessors from inside of the loop (and are thus dominated
- by the loop header). This simplifies transformations such as store-sinking
- that are built into LICM.
- </p>
-
- <p>
- This pass also guarantees that loops will have exactly one backedge.
- </p>
-
- <p>
- Note that the simplifycfg pass will clean up blocks which are split out but
- end up being unnecessary, so usage of this pass should not pessimize
- generated code.
- </p>
-
- <p>
- This pass obviously modifies the CFG, but updates loop information and
- dominator information.
- </p>
-</div>
-
-<!-------------------------------------------------------------------------- -->
-<div class="doc_subsection">
- <a name="lowerallocs">-lowerallocs: Lower allocations from instructions to calls</a>
-</div>
-<div class="doc_text">
- <p>
- Turn <tt>malloc</tt> and <tt>free</tt> instructions into <tt>@malloc</tt> and
- <tt>@free</tt> calls.
+ This pass lowers atomic intrinsics to non-atomic form for use in a known
+ non-preemptible environment.
</p>
<p>
- This is a target-dependent tranformation because it depends on the size of
- data types and alignment constraints.
+ The pass does not verify that the environment is non-preemptible (in
+ general this would require knowledge of the entire call graph of the
+ program including any libraries which may not be available in bitcode form);
+ it simply lowers every atomic intrinsic.
</p>
</div>
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
- <a name="memcpyopt">-memcpyopt: Optimize use of memcpy and friend</a>
+ <a name="memcpyopt">-memcpyopt: MemCpy Optimization</a>
</div>
<div class="doc_text">
<p>
</p>
</div>
-<!-------------------------------------------------------------------------- -->
-<div class="doc_subsection">
- <a name="partialspecialization">-partialspecialization: Partial Specialization</a>
-</div>
-<div class="doc_text">
- <p>This pass finds function arguments that are often a common constant and
- specializes a version of the called function for that constant.
-
- This pass simply does the cloning for functions it specializes. It depends
- on <a href="#ipsccp">IPSCCP</a> and <a href="#deadargelim">DAE</a> to clean up the results.
-
- The initial heuristic favors constant arguments that are used in control
- flow.
- </p>
-</div>
-
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
<a name="prune-eh">-prune-eh: Remove unused exception handling info</a>
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
- <a name="scalarrepl">-scalarrepl: Scalar Replacement of Aggregates</a>
+ <a name="scalarrepl">-scalarrepl: Scalar Replacement of Aggregates (DT)</a>
</div>
<div class="doc_text">
<p>
</p>
</div>
-<!-------------------------------------------------------------------------- -->
-<div class="doc_subsection">
- <a name="sink">-sink: Code Sinking</a>
-</div>
-<div class="doc_text">
- <p>This pass moves instructions into successor blocks, when possible, so that
- they aren't executed on paths where their results aren't needed.
- </p>
-</div>
-
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
<a name="simplify-libcalls">-simplify-libcalls: Simplify well-known library calls</a>
</p>
</div>
-<!-------------------------------------------------------------------------- -->
-<div class="doc_subsection">
- <a name="simplify-libcalls-halfpowr">-simplify-libcalls-halfpowr: Simplify half_powr library calls</a>
-</div>
-<div class="doc_text">
- <p>Simple pass that applies an experimental transformation on calls
- to specific functions.
- </p>
-</div>
-
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
<a name="simplifycfg">-simplifycfg: Simplify the CFG</a>
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
- <a name="split-geps">-split-geps: Split complex GEPs into simple GEPs</a>
+ <a name="sink">-sink: Code sinking</a>
</div>
<div class="doc_text">
- <p>This function breaks GEPs with more than 2 non-zero operands into smaller
- GEPs each with no more than 2 non-zero operands. This exposes redundancy
- between GEPs with common initial operand sequences.
+ <p>This pass moves instructions into successor blocks, when possible, so that
+ they aren't executed on paths where their results aren't needed.
</p>
</div>
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
- <a name="ssi">-ssi: Static Single Information Construction</a>
+ <a name="sretpromotion">-sretpromotion: Promote sret arguments to multiple ret values</a>
</div>
<div class="doc_text">
- <p>This pass converts a list of variables to the Static Single Information
- form.
-
- We are building an on-demand representation, that is, we do not convert
- every single variable in the target function to SSI form. Rather, we receive
- a list of target variables that must be converted. We also do not
- completely convert a target variable to the SSI format. Instead, we only
- change the variable in the points where new information can be attached
- to its live range, that is, at branch points.
+ <p>
+ This pass finds functions that return a struct (using a pointer to the struct
+ as the first argument of the function, marked with the '<tt>sret</tt>' attribute) and
+ replaces them with a new function that simply returns each of the elements of
+ that struct (using multiple return values).
+ </p>
+
+ <p>
+ This pass works under a number of conditions:
</p>
+
+ <ul>
+ <li>The returned struct must not contain other structs</li>
+ <li>The returned struct must only be used to load values from</li>
+ <li>The placeholder struct passed in is the result of an <tt>alloca</tt></li>
+ </ul>
</div>
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
- <a name="ssi-everything">-ssi-everything: Static Single Information Construction (everything, intended for debugging)</a>
+ <a name="strip">-strip: Strip all symbols from a module</a>
</div>
<div class="doc_text">
- <p>A pass that runs <a href="#ssi">SSI</a> on every non-void variable, intended for debugging.
+ <p>
+ performs code stripping. this transformation can delete:
+ </p>
+
+ <ol>
+ <li>names for virtual registers</li>
+ <li>symbols for internal globals and functions</li>
+ <li>debug information</li>
+ </ol>
+
+ <p>
+ note that this transformation makes code much less readable, so it should
+ only be used in situations where the <tt>strip</tt> utility would be used,
+ such as reducing code size or making it harder to reverse engineer code.
</p>
</div>
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
- <a name="strip">-strip: Strip all symbols from a module</a>
+ <a name="strip-dead-debug-info">-strip-dead-debug-info: Strip debug info for unused symbols</a>
</div>
<div class="doc_text">
<p>
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
- <a name="strip-dead-prototypes">-strip-dead-prototypes: Remove unused function declarations</a>
+ <a name="strip-dead-prototypes">-strip-dead-prototypes: Strip Unused Function Prototypes</a>
</div>
<div class="doc_text">
<p>
<a name="strip-debug-declare">-strip-debug-declare: Strip all llvm.dbg.declare intrinsics</a>
</div>
<div class="doc_text">
- <p>This pass implements code stripping. Specifically, it can delete:
+ <p>This pass implements code stripping. Specifically, it can delete:</p>
<ul>
<li>names for virtual registers</li>
<li>symbols for internal globals and functions</li>
<li>debug information</li>
</ul>
+ <p>
Note that this transformation makes code much less readable, so it should
only be used in situations where the 'strip' utility would be used, such as
reducing code size or making it harder to reverse engineer code.
<a name="strip-nondebug">-strip-nondebug: Strip all symbols, except dbg symbols, from a module</a>
</div>
<div class="doc_text">
- <p>This pass implements code stripping. Specifically, it can delete:
+ <p>This pass implements code stripping. Specifically, it can delete:</p>
<ul>
<li>names for virtual registers</li>
<li>symbols for internal globals and functions</li>
<li>debug information</li>
</ul>
+ <p>
Note that this transformation makes code much less readable, so it should
only be used in situations where the 'strip' utility would be used, such as
reducing code size or making it harder to reverse engineer code.
</p>
</div>
-<!-------------------------------------------------------------------------- -->
-<div class="doc_subsection">
- <a name="sretpromotion">-sretpromotion: Promote sret arguments</a>
-</div>
-<div class="doc_text">
- <p>
- This pass finds functions that return a struct (using a pointer to the struct
- as the first argument of the function, marked with the '<tt>sret</tt>' attribute) and
- replaces them with a new function that simply returns each of the elements of
- that struct (using multiple return values).
- </p>
-
- <p>
- This pass works under a number of conditions:
- </p>
-
- <ul>
- <li>The returned struct must not contain other structs</li>
- <li>The returned struct must only be used to load values from</li>
- <li>The placeholder struct passed in is the result of an <tt>alloca</tt></li>
- </ul>
-</div>
-
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
<a name="tailcallelim">-tailcallelim: Tail Call Elimination</a>
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
- <a name="view-dom">-view-dom: View dominator tree of function</a>
+ <a name="view-dom">-view-dom: View dominance tree of function</a>
</div>
<div class="doc_text">
<p>
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
- <a name="view-dom-only">-view-dom-only: View dominator tree of function (with no function
- bodies)
- </a>
+ <a name="view-dom-only">-view-dom-only: View dominance tree of function (with no function bodies)</a>
</div>
<div class="doc_text">
<p>
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
- <a name="view-postdom">-view-postdom: View post dominator tree of function</a>
+ <a name="view-postdom">-view-postdom: View postdominance tree of function</a>
</div>
<div class="doc_text">
<p>
<!-------------------------------------------------------------------------- -->
<div class="doc_subsection">
- <a name="view-postdom-only">-view-postdom-only: View post dominator tree of function (with no
- function bodies)
- </a>
+ <a name="view-postdom-only">-view-postdom-only: View postdominance tree of function (with no function bodies)</a>
</div>
<div class="doc_text">
<p>
src="http://www.w3.org/Icons/valid-html401-blue" alt="Valid HTML 4.01"></a>
<a href="mailto:rspencer@x10sys.com">Reid Spencer</a><br>
- <a href="http://llvm.org">LLVM Compiler Infrastructure</a><br>
+ <a href="http://llvm.org/">LLVM Compiler Infrastructure</a><br>
Last modified: $Date$
</address>
projects / oota-llvm.git / blobdiff