1 //===- PassManagerBuilder.cpp - Build Standard Pass -----------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
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++.
12 //
13 //===----------------------------------------------------------------------===//
14
15
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/Analysis/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"
28
29 using namespace llvm;
30
31 static cl::opt<bool>
32 RunLoopVectorization("vectorize-loops",
33 cl::desc("Run the Loop vectorization passes"));
34
35 static cl::opt<bool>
36 RunBBVectorization("vectorize", cl::desc("Run the BB vectorization passes"));
37
38 static cl::opt<bool>
39 UseGVNAfterVectorization("use-gvn-after-vectorization",
40 cl::init(false), cl::Hidden,
41 cl::desc("Run GVN instead of Early CSE after vectorization passes"));
42
43 static cl::opt<bool> UseNewSROA("use-new-sroa",
44 cl::init(true), cl::Hidden,
45 cl::desc("Enable the new, experimental SROA pass"));
46
PassManagerBuilder()47 PassManagerBuilder::PassManagerBuilder() {
48 OptLevel = 2;
49 SizeLevel = 0;
50 LibraryInfo = 0;
51 Inliner = 0;
52 DisableSimplifyLibCalls = false;
53 DisableUnitAtATime = false;
54 DisableUnrollLoops = false;
55 Vectorize = RunBBVectorization;
56 LoopVectorize = RunLoopVectorization;
57 }
58
~PassManagerBuilder()59 PassManagerBuilder::~PassManagerBuilder() {
60 delete LibraryInfo;
61 delete Inliner;
62 }
63
64 /// Set of global extensions, automatically added as part of the standard set.
65 static ManagedStatic<SmallVector<std::pair<PassManagerBuilder::ExtensionPointTy,
66 PassManagerBuilder::ExtensionFn>, 8> > GlobalExtensions;
67
addGlobalExtension(PassManagerBuilder::ExtensionPointTy Ty,PassManagerBuilder::ExtensionFn Fn)68 void PassManagerBuilder::addGlobalExtension(
69 PassManagerBuilder::ExtensionPointTy Ty,
70 PassManagerBuilder::ExtensionFn Fn) {
71 GlobalExtensions->push_back(std::make_pair(Ty, Fn));
72 }
73
addExtension(ExtensionPointTy Ty,ExtensionFn Fn)74 void PassManagerBuilder::addExtension(ExtensionPointTy Ty, ExtensionFn Fn) {
75 Extensions.push_back(std::make_pair(Ty, Fn));
76 }
77
addExtensionsToPM(ExtensionPointTy ETy,PassManagerBase & PM) const78 void PassManagerBuilder::addExtensionsToPM(ExtensionPointTy ETy,
79 PassManagerBase &PM) const {
80 for (unsigned i = 0, e = GlobalExtensions->size(); i != e; ++i)
81 if ((*GlobalExtensions)[i].first == ETy)
82 (*GlobalExtensions)[i].second(*this, PM);
83 for (unsigned i = 0, e = Extensions.size(); i != e; ++i)
84 if (Extensions[i].first == ETy)
85 Extensions[i].second(*this, PM);
86 }
87
88 void
addInitialAliasAnalysisPasses(PassManagerBase & PM) const89 PassManagerBuilder::addInitialAliasAnalysisPasses(PassManagerBase &PM) const {
90 // Add TypeBasedAliasAnalysis before BasicAliasAnalysis so that
91 // BasicAliasAnalysis wins if they disagree. This is intended to help
92 // support "obvious" type-punning idioms.
93 PM.add(createTypeBasedAliasAnalysisPass());
94 PM.add(createBasicAliasAnalysisPass());
95 }
96
populateFunctionPassManager(FunctionPassManager & FPM)97 void PassManagerBuilder::populateFunctionPassManager(FunctionPassManager &FPM) {
98 addExtensionsToPM(EP_EarlyAsPossible, FPM);
99
100 // Add LibraryInfo if we have some.
101 if (LibraryInfo) FPM.add(new TargetLibraryInfo(*LibraryInfo));
102
103 if (OptLevel == 0) return;
104
105 addInitialAliasAnalysisPasses(FPM);
106
107 FPM.add(createCFGSimplificationPass());
108 if (UseNewSROA)
109 FPM.add(createSROAPass());
110 else
111 FPM.add(createScalarReplAggregatesPass());
112 FPM.add(createEarlyCSEPass());
113 FPM.add(createLowerExpectIntrinsicPass());
114 }
115
populateModulePassManager(PassManagerBase & MPM)116 void PassManagerBuilder::populateModulePassManager(PassManagerBase &MPM) {
117 // If all optimizations are disabled, just run the always-inline pass.
118 if (OptLevel == 0) {
119 if (Inliner) {
120 MPM.add(Inliner);
121 Inliner = 0;
122 }
123
124 // FIXME: This is a HACK! The inliner pass above implicitly creates a CGSCC
125 // pass manager, but we don't want to add extensions into that pass manager.
126 // To prevent this we must insert a no-op module pass to reset the pass
127 // manager to get the same behavior as EP_OptimizerLast in non-O0 builds.
128 if (!GlobalExtensions->empty() || !Extensions.empty())
129 MPM.add(createBarrierNoopPass());
130
131 addExtensionsToPM(EP_EnabledOnOptLevel0, MPM);
132 return;
133 }
134
135 // Add LibraryInfo if we have some.
136 if (LibraryInfo) MPM.add(new TargetLibraryInfo(*LibraryInfo));
137
138 addInitialAliasAnalysisPasses(MPM);
139
140 if (!DisableUnitAtATime) {
141 addExtensionsToPM(EP_ModuleOptimizerEarly, MPM);
142
143 MPM.add(createGlobalOptimizerPass()); // Optimize out global vars
144
145 MPM.add(createIPSCCPPass()); // IP SCCP
146 MPM.add(createDeadArgEliminationPass()); // Dead argument elimination
147
148 MPM.add(createInstructionCombiningPass());// Clean up after IPCP & DAE
149 MPM.add(createCFGSimplificationPass()); // Clean up after IPCP & DAE
150 }
151
152 // Start of CallGraph SCC passes.
153 if (!DisableUnitAtATime)
154 MPM.add(createPruneEHPass()); // Remove dead EH info
155 if (Inliner) {
156 MPM.add(Inliner);
157 Inliner = 0;
158 }
159 if (!DisableUnitAtATime)
160 MPM.add(createFunctionAttrsPass()); // Set readonly/readnone attrs
161 if (OptLevel > 2)
162 MPM.add(createArgumentPromotionPass()); // Scalarize uninlined fn args
163
164 // Start of function pass.
165 // Break up aggregate allocas, using SSAUpdater.
166 if (UseNewSROA)
167 MPM.add(createSROAPass(/*RequiresDomTree*/ false));
168 else
169 MPM.add(createScalarReplAggregatesPass(-1, false));
170 MPM.add(createEarlyCSEPass()); // Catch trivial redundancies
171 if (!DisableSimplifyLibCalls)
172 MPM.add(createSimplifyLibCallsPass()); // Library Call Optimizations
173 MPM.add(createJumpThreadingPass()); // Thread jumps.
174 MPM.add(createCorrelatedValuePropagationPass()); // Propagate conditionals
175 MPM.add(createCFGSimplificationPass()); // Merge & remove BBs
176 MPM.add(createInstructionCombiningPass()); // Combine silly seq's
177
178 MPM.add(createTailCallEliminationPass()); // Eliminate tail calls
179 MPM.add(createCFGSimplificationPass()); // Merge & remove BBs
180 MPM.add(createReassociatePass()); // Reassociate expressions
181 MPM.add(createLoopRotatePass()); // Rotate Loop
182 MPM.add(createLICMPass()); // Hoist loop invariants
183 MPM.add(createLoopUnswitchPass(SizeLevel || OptLevel < 3));
184 MPM.add(createInstructionCombiningPass());
185 MPM.add(createIndVarSimplifyPass()); // Canonicalize indvars
186 MPM.add(createLoopIdiomPass()); // Recognize idioms like memset.
187 MPM.add(createLoopDeletionPass()); // Delete dead loops
188
189 if (LoopVectorize && OptLevel > 2)
190 MPM.add(createLoopVectorizePass());
191
192 if (!DisableUnrollLoops)
193 MPM.add(createLoopUnrollPass()); // Unroll small loops
194 addExtensionsToPM(EP_LoopOptimizerEnd, MPM);
195
196 if (OptLevel > 1)
197 MPM.add(createGVNPass()); // Remove redundancies
198 MPM.add(createMemCpyOptPass()); // Remove memcpy / form memset
199 MPM.add(createSCCPPass()); // Constant prop with SCCP
200
201 // Run instcombine after redundancy elimination to exploit opportunities
202 // opened up by them.
203 MPM.add(createInstructionCombiningPass());
204 MPM.add(createJumpThreadingPass()); // Thread jumps
205 MPM.add(createCorrelatedValuePropagationPass());
206 MPM.add(createDeadStoreEliminationPass()); // Delete dead stores
207
208 addExtensionsToPM(EP_ScalarOptimizerLate, MPM);
209
210 if (Vectorize) {
211 MPM.add(createBBVectorizePass());
212 MPM.add(createInstructionCombiningPass());
213 if (OptLevel > 1 && UseGVNAfterVectorization)
214 MPM.add(createGVNPass()); // Remove redundancies
215 else
216 MPM.add(createEarlyCSEPass()); // Catch trivial redundancies
217
218 // BBVectorize may have significantly shortened a loop body; unroll again.
219 if (!DisableUnrollLoops)
220 MPM.add(createLoopUnrollPass());
221 }
222
223 MPM.add(createAggressiveDCEPass()); // Delete dead instructions
224 MPM.add(createCFGSimplificationPass()); // Merge & remove BBs
225 MPM.add(createInstructionCombiningPass()); // Clean up after everything.
226
227 if (!DisableUnitAtATime) {
228 // FIXME: We shouldn't bother with this anymore.
229 MPM.add(createStripDeadPrototypesPass()); // Get rid of dead prototypes
230
231 // GlobalOpt already deletes dead functions and globals, at -O2 try a
232 // late pass of GlobalDCE. It is capable of deleting dead cycles.
233 if (OptLevel > 1) {
234 MPM.add(createGlobalDCEPass()); // Remove dead fns and globals.
235 MPM.add(createConstantMergePass()); // Merge dup global constants
236 }
237 }
238 addExtensionsToPM(EP_OptimizerLast, MPM);
239 }
240
populateLTOPassManager(PassManagerBase & PM,bool Internalize,bool RunInliner,bool DisableGVNLoadPRE)241 void PassManagerBuilder::populateLTOPassManager(PassManagerBase &PM,
242 bool Internalize,
243 bool RunInliner,
244 bool DisableGVNLoadPRE) {
245 // Provide AliasAnalysis services for optimizations.
246 addInitialAliasAnalysisPasses(PM);
247
248 // Now that composite has been compiled, scan through the module, looking
249 // for a main function. If main is defined, mark all other functions
250 // internal.
251 if (Internalize) {
252 std::vector<const char*> E;
253 E.push_back("main");
254 PM.add(createInternalizePass(E));
255 }
256
257 // Propagate constants at call sites into the functions they call. This
258 // opens opportunities for globalopt (and inlining) by substituting function
259 // pointers passed as arguments to direct uses of functions.
260 PM.add(createIPSCCPPass());
261
262 // Now that we internalized some globals, see if we can hack on them!
263 PM.add(createGlobalOptimizerPass());
264
265 // Linking modules together can lead to duplicated global constants, only
266 // keep one copy of each constant.
267 PM.add(createConstantMergePass());
268
269 // Remove unused arguments from functions.
270 PM.add(createDeadArgEliminationPass());
271
272 // Reduce the code after globalopt and ipsccp. Both can open up significant
273 // simplification opportunities, and both can propagate functions through
274 // function pointers. When this happens, we often have to resolve varargs
275 // calls, etc, so let instcombine do this.
276 PM.add(createInstructionCombiningPass());
277
278 // Inline small functions
279 if (RunInliner)
280 PM.add(createFunctionInliningPass());
281
282 PM.add(createPruneEHPass()); // Remove dead EH info.
283
284 // Optimize globals again if we ran the inliner.
285 if (RunInliner)
286 PM.add(createGlobalOptimizerPass());
287 PM.add(createGlobalDCEPass()); // Remove dead functions.
288
289 // If we didn't decide to inline a function, check to see if we can
290 // transform it to pass arguments by value instead of by reference.
291 PM.add(createArgumentPromotionPass());
292
293 // The IPO passes may leave cruft around. Clean up after them.
294 PM.add(createInstructionCombiningPass());
295 PM.add(createJumpThreadingPass());
296 // Break up allocas
297 if (UseNewSROA)
298 PM.add(createSROAPass());
299 else
300 PM.add(createScalarReplAggregatesPass());
301
302 // Run a few AA driven optimizations here and now, to cleanup the code.
303 PM.add(createFunctionAttrsPass()); // Add nocapture.
304 PM.add(createGlobalsModRefPass()); // IP alias analysis.
305
306 PM.add(createLICMPass()); // Hoist loop invariants.
307 PM.add(createGVNPass(DisableGVNLoadPRE)); // Remove redundancies.
308 PM.add(createMemCpyOptPass()); // Remove dead memcpys.
309 // Nuke dead stores.
310 PM.add(createDeadStoreEliminationPass());
311
312 // Cleanup and simplify the code after the scalar optimizations.
313 PM.add(createInstructionCombiningPass());
314
315 PM.add(createJumpThreadingPass());
316
317 // Delete basic blocks, which optimization passes may have killed.
318 PM.add(createCFGSimplificationPass());
319
320 // Now that we have optimized the program, discard unreachable functions.
321 PM.add(createGlobalDCEPass());
322 }
323
LLVMPassManagerBuilderCreate()324 LLVMPassManagerBuilderRef LLVMPassManagerBuilderCreate() {
325 PassManagerBuilder *PMB = new PassManagerBuilder();
326 return wrap(PMB);
327 }
328
LLVMPassManagerBuilderDispose(LLVMPassManagerBuilderRef PMB)329 void LLVMPassManagerBuilderDispose(LLVMPassManagerBuilderRef PMB) {
330 PassManagerBuilder *Builder = unwrap(PMB);
331 delete Builder;
332 }
333
334 void
LLVMPassManagerBuilderSetOptLevel(LLVMPassManagerBuilderRef PMB,unsigned OptLevel)335 LLVMPassManagerBuilderSetOptLevel(LLVMPassManagerBuilderRef PMB,
336 unsigned OptLevel) {
337 PassManagerBuilder *Builder = unwrap(PMB);
338 Builder->OptLevel = OptLevel;
339 }
340
341 void
LLVMPassManagerBuilderSetSizeLevel(LLVMPassManagerBuilderRef PMB,unsigned SizeLevel)342 LLVMPassManagerBuilderSetSizeLevel(LLVMPassManagerBuilderRef PMB,
343 unsigned SizeLevel) {
344 PassManagerBuilder *Builder = unwrap(PMB);
345 Builder->SizeLevel = SizeLevel;
346 }
347
348 void
LLVMPassManagerBuilderSetDisableUnitAtATime(LLVMPassManagerBuilderRef PMB,LLVMBool Value)349 LLVMPassManagerBuilderSetDisableUnitAtATime(LLVMPassManagerBuilderRef PMB,
350 LLVMBool Value) {
351 PassManagerBuilder *Builder = unwrap(PMB);
352 Builder->DisableUnitAtATime = Value;
353 }
354
355 void
LLVMPassManagerBuilderSetDisableUnrollLoops(LLVMPassManagerBuilderRef PMB,LLVMBool Value)356 LLVMPassManagerBuilderSetDisableUnrollLoops(LLVMPassManagerBuilderRef PMB,
357 LLVMBool Value) {
358 PassManagerBuilder *Builder = unwrap(PMB);
359 Builder->DisableUnrollLoops = Value;
360 }
361
362 void
LLVMPassManagerBuilderSetDisableSimplifyLibCalls(LLVMPassManagerBuilderRef PMB,LLVMBool Value)363 LLVMPassManagerBuilderSetDisableSimplifyLibCalls(LLVMPassManagerBuilderRef PMB,
364 LLVMBool Value) {
365 PassManagerBuilder *Builder = unwrap(PMB);
366 Builder->DisableSimplifyLibCalls = Value;
367 }
368
369 void
LLVMPassManagerBuilderUseInlinerWithThreshold(LLVMPassManagerBuilderRef PMB,unsigned Threshold)370 LLVMPassManagerBuilderUseInlinerWithThreshold(LLVMPassManagerBuilderRef PMB,
371 unsigned Threshold) {
372 PassManagerBuilder *Builder = unwrap(PMB);
373 Builder->Inliner = createFunctionInliningPass(Threshold);
374 }
375
376 void
LLVMPassManagerBuilderPopulateFunctionPassManager(LLVMPassManagerBuilderRef PMB,LLVMPassManagerRef PM)377 LLVMPassManagerBuilderPopulateFunctionPassManager(LLVMPassManagerBuilderRef PMB,
378 LLVMPassManagerRef PM) {
379 PassManagerBuilder *Builder = unwrap(PMB);
380 FunctionPassManager *FPM = unwrap<FunctionPassManager>(PM);
381 Builder->populateFunctionPassManager(*FPM);
382 }
383
384 void
LLVMPassManagerBuilderPopulateModulePassManager(LLVMPassManagerBuilderRef PMB,LLVMPassManagerRef PM)385 LLVMPassManagerBuilderPopulateModulePassManager(LLVMPassManagerBuilderRef PMB,
386 LLVMPassManagerRef PM) {
387 PassManagerBuilder *Builder = unwrap(PMB);
388 PassManagerBase *MPM = unwrap(PM);
389 Builder->populateModulePassManager(*MPM);
390 }
391
LLVMPassManagerBuilderPopulateLTOPassManager(LLVMPassManagerBuilderRef PMB,LLVMPassManagerRef PM,LLVMBool Internalize,LLVMBool RunInliner)392 void LLVMPassManagerBuilderPopulateLTOPassManager(LLVMPassManagerBuilderRef PMB,
393 LLVMPassManagerRef PM,
394 LLVMBool Internalize,
395 LLVMBool RunInliner) {
396 PassManagerBuilder *Builder = unwrap(PMB);
397 PassManagerBase *LPM = unwrap(PM);
398 Builder->populateLTOPassManager(*LPM, Internalize != 0, RunInliner != 0);
399 }
400