1 //===- PassManagerBuilder.cpp - Build Standard Pass -----------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines the PassManagerBuilder class, which is used to set up a
11 // "standard" optimization sequence suitable for languages like C and C++.
13 //===----------------------------------------------------------------------===//
16 #include "llvm/Transforms/IPO/PassManagerBuilder.h"
17 #include "llvm-c/Transforms/PassManagerBuilder.h"
18 #include "llvm/ADT/SmallVector.h"
19 #include "llvm/Analysis/Passes.h"
20 #include "llvm/IR/Verifier.h"
21 #include "llvm/PassManager.h"
22 #include "llvm/Support/CommandLine.h"
23 #include "llvm/Support/ManagedStatic.h"
24 #include "llvm/Target/TargetLibraryInfo.h"
25 #include "llvm/Transforms/IPO.h"
26 #include "llvm/Transforms/Scalar.h"
27 #include "llvm/Transforms/Vectorize.h"
32 RunLoopVectorization("vectorize-loops", cl::Hidden,
33 cl::desc("Run the Loop vectorization passes"));
36 RunSLPVectorization("vectorize-slp", cl::Hidden,
37 cl::desc("Run the SLP vectorization passes"));
40 RunBBVectorization("vectorize-slp-aggressive", cl::Hidden,
41 cl::desc("Run the BB vectorization passes"));
44 UseGVNAfterVectorization("use-gvn-after-vectorization",
45 cl::init(false), cl::Hidden,
46 cl::desc("Run GVN instead of Early CSE after vectorization passes"));
48 static cl::opt<bool> UseNewSROA("use-new-sroa",
49 cl::init(true), cl::Hidden,
50 cl::desc("Enable the new, experimental SROA pass"));
53 RunLoopRerolling("reroll-loops", cl::Hidden,
54 cl::desc("Run the loop rerolling pass"));
56 PassManagerBuilder::PassManagerBuilder() {
59 LibraryInfo = nullptr;
61 DisableTailCalls = false;
62 DisableUnitAtATime = false;
63 DisableUnrollLoops = false;
64 BBVectorize = RunBBVectorization;
65 SLPVectorize = RunSLPVectorization;
66 LoopVectorize = RunLoopVectorization;
67 RerollLoops = RunLoopRerolling;
70 PassManagerBuilder::~PassManagerBuilder() {
75 /// Set of global extensions, automatically added as part of the standard set.
76 static ManagedStatic<SmallVector<std::pair<PassManagerBuilder::ExtensionPointTy,
77 PassManagerBuilder::ExtensionFn>, 8> > GlobalExtensions;
79 void PassManagerBuilder::addGlobalExtension(
80 PassManagerBuilder::ExtensionPointTy Ty,
81 PassManagerBuilder::ExtensionFn Fn) {
82 GlobalExtensions->push_back(std::make_pair(Ty, Fn));
85 void PassManagerBuilder::addExtension(ExtensionPointTy Ty, ExtensionFn Fn) {
86 Extensions.push_back(std::make_pair(Ty, Fn));
89 void PassManagerBuilder::addExtensionsToPM(ExtensionPointTy ETy,
90 PassManagerBase &PM) const {
91 for (unsigned i = 0, e = GlobalExtensions->size(); i != e; ++i)
92 if ((*GlobalExtensions)[i].first == ETy)
93 (*GlobalExtensions)[i].second(*this, PM);
94 for (unsigned i = 0, e = Extensions.size(); i != e; ++i)
95 if (Extensions[i].first == ETy)
96 Extensions[i].second(*this, PM);
100 PassManagerBuilder::addInitialAliasAnalysisPasses(PassManagerBase &PM) const {
101 // Add TypeBasedAliasAnalysis before BasicAliasAnalysis so that
102 // BasicAliasAnalysis wins if they disagree. This is intended to help
103 // support "obvious" type-punning idioms.
104 PM.add(createTypeBasedAliasAnalysisPass());
105 PM.add(createBasicAliasAnalysisPass());
108 void PassManagerBuilder::populateFunctionPassManager(FunctionPassManager &FPM) {
109 addExtensionsToPM(EP_EarlyAsPossible, FPM);
111 // Add LibraryInfo if we have some.
112 if (LibraryInfo) FPM.add(new TargetLibraryInfo(*LibraryInfo));
114 if (OptLevel == 0) return;
116 addInitialAliasAnalysisPasses(FPM);
118 FPM.add(createCFGSimplificationPass());
120 FPM.add(createSROAPass());
122 FPM.add(createScalarReplAggregatesPass());
123 FPM.add(createEarlyCSEPass());
124 FPM.add(createLowerExpectIntrinsicPass());
127 void PassManagerBuilder::populateModulePassManager(PassManagerBase &MPM) {
128 // If all optimizations are disabled, just run the always-inline pass.
135 // FIXME: This is a HACK! The inliner pass above implicitly creates a CGSCC
136 // pass manager, but we don't want to add extensions into that pass manager.
137 // To prevent this we must insert a no-op module pass to reset the pass
138 // manager to get the same behavior as EP_OptimizerLast in non-O0 builds.
139 if (!GlobalExtensions->empty() || !Extensions.empty())
140 MPM.add(createBarrierNoopPass());
142 addExtensionsToPM(EP_EnabledOnOptLevel0, MPM);
146 // Add LibraryInfo if we have some.
147 if (LibraryInfo) MPM.add(new TargetLibraryInfo(*LibraryInfo));
149 addInitialAliasAnalysisPasses(MPM);
151 if (!DisableUnitAtATime) {
152 addExtensionsToPM(EP_ModuleOptimizerEarly, MPM);
154 MPM.add(createGlobalOptimizerPass()); // Optimize out global vars
156 MPM.add(createIPSCCPPass()); // IP SCCP
157 MPM.add(createDeadArgEliminationPass()); // Dead argument elimination
159 MPM.add(createInstructionCombiningPass());// Clean up after IPCP & DAE
160 MPM.add(createCFGSimplificationPass()); // Clean up after IPCP & DAE
163 // Start of CallGraph SCC passes.
164 if (!DisableUnitAtATime)
165 MPM.add(createPruneEHPass()); // Remove dead EH info
170 if (!DisableUnitAtATime)
171 MPM.add(createFunctionAttrsPass()); // Set readonly/readnone attrs
173 MPM.add(createArgumentPromotionPass()); // Scalarize uninlined fn args
175 // Start of function pass.
176 // Break up aggregate allocas, using SSAUpdater.
178 MPM.add(createSROAPass(/*RequiresDomTree*/ false));
180 MPM.add(createScalarReplAggregatesPass(-1, false));
181 MPM.add(createEarlyCSEPass()); // Catch trivial redundancies
182 MPM.add(createJumpThreadingPass()); // Thread jumps.
183 MPM.add(createCorrelatedValuePropagationPass()); // Propagate conditionals
184 MPM.add(createCFGSimplificationPass()); // Merge & remove BBs
185 MPM.add(createInstructionCombiningPass()); // Combine silly seq's
187 if (!DisableTailCalls)
188 MPM.add(createTailCallEliminationPass()); // Eliminate tail calls
189 MPM.add(createCFGSimplificationPass()); // Merge & remove BBs
190 MPM.add(createReassociatePass()); // Reassociate expressions
191 MPM.add(createLoopRotatePass()); // Rotate Loop
192 MPM.add(createLICMPass()); // Hoist loop invariants
193 MPM.add(createLoopUnswitchPass(SizeLevel || OptLevel < 3));
194 MPM.add(createInstructionCombiningPass());
195 MPM.add(createIndVarSimplifyPass()); // Canonicalize indvars
196 MPM.add(createLoopIdiomPass()); // Recognize idioms like memset.
197 MPM.add(createLoopDeletionPass()); // Delete dead loops
199 if (!DisableUnrollLoops)
200 MPM.add(createSimpleLoopUnrollPass()); // Unroll small loops
201 addExtensionsToPM(EP_LoopOptimizerEnd, MPM);
204 MPM.add(createGVNPass()); // Remove redundancies
205 MPM.add(createMemCpyOptPass()); // Remove memcpy / form memset
206 MPM.add(createSCCPPass()); // Constant prop with SCCP
208 // Run instcombine after redundancy elimination to exploit opportunities
209 // opened up by them.
210 MPM.add(createInstructionCombiningPass());
211 MPM.add(createJumpThreadingPass()); // Thread jumps
212 MPM.add(createCorrelatedValuePropagationPass());
213 MPM.add(createDeadStoreEliminationPass()); // Delete dead stores
215 addExtensionsToPM(EP_ScalarOptimizerLate, MPM);
218 MPM.add(createLoopRerollPass());
220 MPM.add(createSLPVectorizerPass()); // Vectorize parallel scalar chains.
223 MPM.add(createBBVectorizePass());
224 MPM.add(createInstructionCombiningPass());
225 if (OptLevel > 1 && UseGVNAfterVectorization)
226 MPM.add(createGVNPass()); // Remove redundancies
228 MPM.add(createEarlyCSEPass()); // Catch trivial redundancies
230 // BBVectorize may have significantly shortened a loop body; unroll again.
231 if (!DisableUnrollLoops)
232 MPM.add(createLoopUnrollPass());
235 MPM.add(createAggressiveDCEPass()); // Delete dead instructions
236 MPM.add(createCFGSimplificationPass()); // Merge & remove BBs
237 MPM.add(createInstructionCombiningPass()); // Clean up after everything.
239 // FIXME: This is a HACK! The inliner pass above implicitly creates a CGSCC
240 // pass manager that we are specifically trying to avoid. To prevent this
241 // we must insert a no-op module pass to reset the pass manager.
242 MPM.add(createBarrierNoopPass());
243 MPM.add(createLoopVectorizePass(DisableUnrollLoops, LoopVectorize));
244 // FIXME: Because of #pragma vectorize enable, the passes below are always
245 // inserted in the pipeline, even when the vectorizer doesn't run (ex. when
246 // on -O1 and no #pragma is found). Would be good to have these two passes
247 // as function calls, so that we can only pass them when the vectorizer
249 MPM.add(createInstructionCombiningPass());
250 MPM.add(createCFGSimplificationPass());
252 if (!DisableUnrollLoops)
253 MPM.add(createLoopUnrollPass()); // Unroll small loops
255 if (!DisableUnitAtATime) {
256 // FIXME: We shouldn't bother with this anymore.
257 MPM.add(createStripDeadPrototypesPass()); // Get rid of dead prototypes
259 // GlobalOpt already deletes dead functions and globals, at -O2 try a
260 // late pass of GlobalDCE. It is capable of deleting dead cycles.
262 MPM.add(createGlobalDCEPass()); // Remove dead fns and globals.
263 MPM.add(createConstantMergePass()); // Merge dup global constants
266 addExtensionsToPM(EP_OptimizerLast, MPM);
269 void PassManagerBuilder::populateLTOPassManager(PassManagerBase &PM,
272 bool DisableGVNLoadPRE) {
273 // Provide AliasAnalysis services for optimizations.
274 addInitialAliasAnalysisPasses(PM);
276 // Now that composite has been compiled, scan through the module, looking
277 // for a main function. If main is defined, mark all other functions
280 PM.add(createInternalizePass("main"));
282 // Propagate constants at call sites into the functions they call. This
283 // opens opportunities for globalopt (and inlining) by substituting function
284 // pointers passed as arguments to direct uses of functions.
285 PM.add(createIPSCCPPass());
287 // Now that we internalized some globals, see if we can hack on them!
288 PM.add(createGlobalOptimizerPass());
290 // Linking modules together can lead to duplicated global constants, only
291 // keep one copy of each constant.
292 PM.add(createConstantMergePass());
294 // Remove unused arguments from functions.
295 PM.add(createDeadArgEliminationPass());
297 // Reduce the code after globalopt and ipsccp. Both can open up significant
298 // simplification opportunities, and both can propagate functions through
299 // function pointers. When this happens, we often have to resolve varargs
300 // calls, etc, so let instcombine do this.
301 PM.add(createInstructionCombiningPass());
303 // Inline small functions
305 PM.add(createFunctionInliningPass());
307 PM.add(createPruneEHPass()); // Remove dead EH info.
309 // Optimize globals again if we ran the inliner.
311 PM.add(createGlobalOptimizerPass());
312 PM.add(createGlobalDCEPass()); // Remove dead functions.
314 // If we didn't decide to inline a function, check to see if we can
315 // transform it to pass arguments by value instead of by reference.
316 PM.add(createArgumentPromotionPass());
318 // The IPO passes may leave cruft around. Clean up after them.
319 PM.add(createInstructionCombiningPass());
320 PM.add(createJumpThreadingPass());
324 PM.add(createSROAPass());
326 PM.add(createScalarReplAggregatesPass());
328 // Run a few AA driven optimizations here and now, to cleanup the code.
329 PM.add(createFunctionAttrsPass()); // Add nocapture.
330 PM.add(createGlobalsModRefPass()); // IP alias analysis.
332 PM.add(createLICMPass()); // Hoist loop invariants.
333 PM.add(createGVNPass(DisableGVNLoadPRE)); // Remove redundancies.
334 PM.add(createMemCpyOptPass()); // Remove dead memcpys.
337 PM.add(createDeadStoreEliminationPass());
339 // More loops are countable; try to optimize them.
340 PM.add(createIndVarSimplifyPass());
341 PM.add(createLoopDeletionPass());
342 PM.add(createLoopVectorizePass(true, true));
344 // Cleanup and simplify the code after the scalar optimizations.
345 PM.add(createInstructionCombiningPass());
347 PM.add(createJumpThreadingPass());
349 // Delete basic blocks, which optimization passes may have killed.
350 PM.add(createCFGSimplificationPass());
352 // Now that we have optimized the program, discard unreachable functions.
353 PM.add(createGlobalDCEPass());
356 inline PassManagerBuilder *unwrap(LLVMPassManagerBuilderRef P) {
357 return reinterpret_cast<PassManagerBuilder*>(P);
360 inline LLVMPassManagerBuilderRef wrap(PassManagerBuilder *P) {
361 return reinterpret_cast<LLVMPassManagerBuilderRef>(P);
364 LLVMPassManagerBuilderRef LLVMPassManagerBuilderCreate() {
365 PassManagerBuilder *PMB = new PassManagerBuilder();
369 void LLVMPassManagerBuilderDispose(LLVMPassManagerBuilderRef PMB) {
370 PassManagerBuilder *Builder = unwrap(PMB);
375 LLVMPassManagerBuilderSetOptLevel(LLVMPassManagerBuilderRef PMB,
377 PassManagerBuilder *Builder = unwrap(PMB);
378 Builder->OptLevel = OptLevel;
382 LLVMPassManagerBuilderSetSizeLevel(LLVMPassManagerBuilderRef PMB,
383 unsigned SizeLevel) {
384 PassManagerBuilder *Builder = unwrap(PMB);
385 Builder->SizeLevel = SizeLevel;
389 LLVMPassManagerBuilderSetDisableUnitAtATime(LLVMPassManagerBuilderRef PMB,
391 PassManagerBuilder *Builder = unwrap(PMB);
392 Builder->DisableUnitAtATime = Value;
396 LLVMPassManagerBuilderSetDisableUnrollLoops(LLVMPassManagerBuilderRef PMB,
398 PassManagerBuilder *Builder = unwrap(PMB);
399 Builder->DisableUnrollLoops = Value;
403 LLVMPassManagerBuilderSetDisableSimplifyLibCalls(LLVMPassManagerBuilderRef PMB,
405 // NOTE: The simplify-libcalls pass has been removed.
409 LLVMPassManagerBuilderUseInlinerWithThreshold(LLVMPassManagerBuilderRef PMB,
410 unsigned Threshold) {
411 PassManagerBuilder *Builder = unwrap(PMB);
412 Builder->Inliner = createFunctionInliningPass(Threshold);
416 LLVMPassManagerBuilderPopulateFunctionPassManager(LLVMPassManagerBuilderRef PMB,
417 LLVMPassManagerRef PM) {
418 PassManagerBuilder *Builder = unwrap(PMB);
419 FunctionPassManager *FPM = unwrap<FunctionPassManager>(PM);
420 Builder->populateFunctionPassManager(*FPM);
424 LLVMPassManagerBuilderPopulateModulePassManager(LLVMPassManagerBuilderRef PMB,
425 LLVMPassManagerRef PM) {
426 PassManagerBuilder *Builder = unwrap(PMB);
427 PassManagerBase *MPM = unwrap(PM);
428 Builder->populateModulePassManager(*MPM);
431 void LLVMPassManagerBuilderPopulateLTOPassManager(LLVMPassManagerBuilderRef PMB,
432 LLVMPassManagerRef PM,
433 LLVMBool Internalize,
434 LLVMBool RunInliner) {
435 PassManagerBuilder *Builder = unwrap(PMB);
436 PassManagerBase *LPM = unwrap(PM);
437 Builder->populateLTOPassManager(*LPM, Internalize != 0, RunInliner != 0);