clang  3.7.0
CGStmt.cpp
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1 //===--- CGStmt.cpp - Emit LLVM Code from Statements ----------------------===//
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 contains code to emit Stmt nodes as LLVM code.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "CodeGenFunction.h"
15 #include "CGDebugInfo.h"
16 #include "CodeGenModule.h"
17 #include "TargetInfo.h"
18 #include "clang/AST/StmtVisitor.h"
20 #include "clang/Basic/TargetInfo.h"
21 #include "clang/Sema/LoopHint.h"
23 #include "llvm/ADT/StringExtras.h"
24 #include "llvm/IR/CallSite.h"
25 #include "llvm/IR/DataLayout.h"
26 #include "llvm/IR/InlineAsm.h"
27 #include "llvm/IR/Intrinsics.h"
28 using namespace clang;
29 using namespace CodeGen;
30 
31 //===----------------------------------------------------------------------===//
32 // Statement Emission
33 //===----------------------------------------------------------------------===//
34 
36  if (CGDebugInfo *DI = getDebugInfo()) {
37  SourceLocation Loc;
38  Loc = S->getLocStart();
39  DI->EmitLocation(Builder, Loc);
40 
41  LastStopPoint = Loc;
42  }
43 }
44 
46  assert(S && "Null statement?");
47  PGO.setCurrentStmt(S);
48 
49  // These statements have their own debug info handling.
50  if (EmitSimpleStmt(S))
51  return;
52 
53  // Check if we are generating unreachable code.
54  if (!HaveInsertPoint()) {
55  // If so, and the statement doesn't contain a label, then we do not need to
56  // generate actual code. This is safe because (1) the current point is
57  // unreachable, so we don't need to execute the code, and (2) we've already
58  // handled the statements which update internal data structures (like the
59  // local variable map) which could be used by subsequent statements.
60  if (!ContainsLabel(S)) {
61  // Verify that any decl statements were handled as simple, they may be in
62  // scope of subsequent reachable statements.
63  assert(!isa<DeclStmt>(*S) && "Unexpected DeclStmt!");
64  return;
65  }
66 
67  // Otherwise, make a new block to hold the code.
69  }
70 
71  // Generate a stoppoint if we are emitting debug info.
72  EmitStopPoint(S);
73 
74  switch (S->getStmtClass()) {
75  case Stmt::NoStmtClass:
76  case Stmt::CXXCatchStmtClass:
77  case Stmt::SEHExceptStmtClass:
78  case Stmt::SEHFinallyStmtClass:
79  case Stmt::MSDependentExistsStmtClass:
80  llvm_unreachable("invalid statement class to emit generically");
81  case Stmt::NullStmtClass:
82  case Stmt::CompoundStmtClass:
83  case Stmt::DeclStmtClass:
84  case Stmt::LabelStmtClass:
85  case Stmt::AttributedStmtClass:
86  case Stmt::GotoStmtClass:
87  case Stmt::BreakStmtClass:
88  case Stmt::ContinueStmtClass:
89  case Stmt::DefaultStmtClass:
90  case Stmt::CaseStmtClass:
91  case Stmt::SEHLeaveStmtClass:
92  llvm_unreachable("should have emitted these statements as simple");
93 
94 #define STMT(Type, Base)
95 #define ABSTRACT_STMT(Op)
96 #define EXPR(Type, Base) \
97  case Stmt::Type##Class:
98 #include "clang/AST/StmtNodes.inc"
99  {
100  // Remember the block we came in on.
101  llvm::BasicBlock *incoming = Builder.GetInsertBlock();
102  assert(incoming && "expression emission must have an insertion point");
103 
104  EmitIgnoredExpr(cast<Expr>(S));
105 
106  llvm::BasicBlock *outgoing = Builder.GetInsertBlock();
107  assert(outgoing && "expression emission cleared block!");
108 
109  // The expression emitters assume (reasonably!) that the insertion
110  // point is always set. To maintain that, the call-emission code
111  // for noreturn functions has to enter a new block with no
112  // predecessors. We want to kill that block and mark the current
113  // insertion point unreachable in the common case of a call like
114  // "exit();". Since expression emission doesn't otherwise create
115  // blocks with no predecessors, we can just test for that.
116  // However, we must be careful not to do this to our incoming
117  // block, because *statement* emission does sometimes create
118  // reachable blocks which will have no predecessors until later in
119  // the function. This occurs with, e.g., labels that are not
120  // reachable by fallthrough.
121  if (incoming != outgoing && outgoing->use_empty()) {
122  outgoing->eraseFromParent();
123  Builder.ClearInsertionPoint();
124  }
125  break;
126  }
127 
128  case Stmt::IndirectGotoStmtClass:
129  EmitIndirectGotoStmt(cast<IndirectGotoStmt>(*S)); break;
130 
131  case Stmt::IfStmtClass: EmitIfStmt(cast<IfStmt>(*S)); break;
132  case Stmt::WhileStmtClass: EmitWhileStmt(cast<WhileStmt>(*S)); break;
133  case Stmt::DoStmtClass: EmitDoStmt(cast<DoStmt>(*S)); break;
134  case Stmt::ForStmtClass: EmitForStmt(cast<ForStmt>(*S)); break;
135 
136  case Stmt::ReturnStmtClass: EmitReturnStmt(cast<ReturnStmt>(*S)); break;
137 
138  case Stmt::SwitchStmtClass: EmitSwitchStmt(cast<SwitchStmt>(*S)); break;
139  case Stmt::GCCAsmStmtClass: // Intentional fall-through.
140  case Stmt::MSAsmStmtClass: EmitAsmStmt(cast<AsmStmt>(*S)); break;
141  case Stmt::CapturedStmtClass: {
142  const CapturedStmt *CS = cast<CapturedStmt>(S);
144  }
145  break;
146  case Stmt::ObjCAtTryStmtClass:
147  EmitObjCAtTryStmt(cast<ObjCAtTryStmt>(*S));
148  break;
149  case Stmt::ObjCAtCatchStmtClass:
150  llvm_unreachable(
151  "@catch statements should be handled by EmitObjCAtTryStmt");
152  case Stmt::ObjCAtFinallyStmtClass:
153  llvm_unreachable(
154  "@finally statements should be handled by EmitObjCAtTryStmt");
155  case Stmt::ObjCAtThrowStmtClass:
156  EmitObjCAtThrowStmt(cast<ObjCAtThrowStmt>(*S));
157  break;
158  case Stmt::ObjCAtSynchronizedStmtClass:
159  EmitObjCAtSynchronizedStmt(cast<ObjCAtSynchronizedStmt>(*S));
160  break;
161  case Stmt::ObjCForCollectionStmtClass:
162  EmitObjCForCollectionStmt(cast<ObjCForCollectionStmt>(*S));
163  break;
164  case Stmt::ObjCAutoreleasePoolStmtClass:
165  EmitObjCAutoreleasePoolStmt(cast<ObjCAutoreleasePoolStmt>(*S));
166  break;
167 
168  case Stmt::CXXTryStmtClass:
169  EmitCXXTryStmt(cast<CXXTryStmt>(*S));
170  break;
171  case Stmt::CXXForRangeStmtClass:
172  EmitCXXForRangeStmt(cast<CXXForRangeStmt>(*S));
173  break;
174  case Stmt::SEHTryStmtClass:
175  EmitSEHTryStmt(cast<SEHTryStmt>(*S));
176  break;
177  case Stmt::OMPParallelDirectiveClass:
178  EmitOMPParallelDirective(cast<OMPParallelDirective>(*S));
179  break;
180  case Stmt::OMPSimdDirectiveClass:
181  EmitOMPSimdDirective(cast<OMPSimdDirective>(*S));
182  break;
183  case Stmt::OMPForDirectiveClass:
184  EmitOMPForDirective(cast<OMPForDirective>(*S));
185  break;
186  case Stmt::OMPForSimdDirectiveClass:
187  EmitOMPForSimdDirective(cast<OMPForSimdDirective>(*S));
188  break;
189  case Stmt::OMPSectionsDirectiveClass:
190  EmitOMPSectionsDirective(cast<OMPSectionsDirective>(*S));
191  break;
192  case Stmt::OMPSectionDirectiveClass:
193  EmitOMPSectionDirective(cast<OMPSectionDirective>(*S));
194  break;
195  case Stmt::OMPSingleDirectiveClass:
196  EmitOMPSingleDirective(cast<OMPSingleDirective>(*S));
197  break;
198  case Stmt::OMPMasterDirectiveClass:
199  EmitOMPMasterDirective(cast<OMPMasterDirective>(*S));
200  break;
201  case Stmt::OMPCriticalDirectiveClass:
202  EmitOMPCriticalDirective(cast<OMPCriticalDirective>(*S));
203  break;
204  case Stmt::OMPParallelForDirectiveClass:
205  EmitOMPParallelForDirective(cast<OMPParallelForDirective>(*S));
206  break;
207  case Stmt::OMPParallelForSimdDirectiveClass:
208  EmitOMPParallelForSimdDirective(cast<OMPParallelForSimdDirective>(*S));
209  break;
210  case Stmt::OMPParallelSectionsDirectiveClass:
211  EmitOMPParallelSectionsDirective(cast<OMPParallelSectionsDirective>(*S));
212  break;
213  case Stmt::OMPTaskDirectiveClass:
214  EmitOMPTaskDirective(cast<OMPTaskDirective>(*S));
215  break;
216  case Stmt::OMPTaskyieldDirectiveClass:
217  EmitOMPTaskyieldDirective(cast<OMPTaskyieldDirective>(*S));
218  break;
219  case Stmt::OMPBarrierDirectiveClass:
220  EmitOMPBarrierDirective(cast<OMPBarrierDirective>(*S));
221  break;
222  case Stmt::OMPTaskwaitDirectiveClass:
223  EmitOMPTaskwaitDirective(cast<OMPTaskwaitDirective>(*S));
224  break;
225  case Stmt::OMPTaskgroupDirectiveClass:
226  EmitOMPTaskgroupDirective(cast<OMPTaskgroupDirective>(*S));
227  break;
228  case Stmt::OMPFlushDirectiveClass:
229  EmitOMPFlushDirective(cast<OMPFlushDirective>(*S));
230  break;
231  case Stmt::OMPOrderedDirectiveClass:
232  EmitOMPOrderedDirective(cast<OMPOrderedDirective>(*S));
233  break;
234  case Stmt::OMPAtomicDirectiveClass:
235  EmitOMPAtomicDirective(cast<OMPAtomicDirective>(*S));
236  break;
237  case Stmt::OMPTargetDirectiveClass:
238  EmitOMPTargetDirective(cast<OMPTargetDirective>(*S));
239  break;
240  case Stmt::OMPTeamsDirectiveClass:
241  EmitOMPTeamsDirective(cast<OMPTeamsDirective>(*S));
242  break;
243  case Stmt::OMPCancellationPointDirectiveClass:
244  EmitOMPCancellationPointDirective(cast<OMPCancellationPointDirective>(*S));
245  break;
246  case Stmt::OMPCancelDirectiveClass:
247  EmitOMPCancelDirective(cast<OMPCancelDirective>(*S));
248  break;
249  }
250 }
251 
253  switch (S->getStmtClass()) {
254  default: return false;
255  case Stmt::NullStmtClass: break;
256  case Stmt::CompoundStmtClass: EmitCompoundStmt(cast<CompoundStmt>(*S)); break;
257  case Stmt::DeclStmtClass: EmitDeclStmt(cast<DeclStmt>(*S)); break;
258  case Stmt::LabelStmtClass: EmitLabelStmt(cast<LabelStmt>(*S)); break;
259  case Stmt::AttributedStmtClass:
260  EmitAttributedStmt(cast<AttributedStmt>(*S)); break;
261  case Stmt::GotoStmtClass: EmitGotoStmt(cast<GotoStmt>(*S)); break;
262  case Stmt::BreakStmtClass: EmitBreakStmt(cast<BreakStmt>(*S)); break;
263  case Stmt::ContinueStmtClass: EmitContinueStmt(cast<ContinueStmt>(*S)); break;
264  case Stmt::DefaultStmtClass: EmitDefaultStmt(cast<DefaultStmt>(*S)); break;
265  case Stmt::CaseStmtClass: EmitCaseStmt(cast<CaseStmt>(*S)); break;
266  case Stmt::SEHLeaveStmtClass: EmitSEHLeaveStmt(cast<SEHLeaveStmt>(*S)); break;
267  }
268 
269  return true;
270 }
271 
272 /// EmitCompoundStmt - Emit a compound statement {..} node. If GetLast is true,
273 /// this captures the expression result of the last sub-statement and returns it
274 /// (for use by the statement expression extension).
276  AggValueSlot AggSlot) {
277  PrettyStackTraceLoc CrashInfo(getContext().getSourceManager(),S.getLBracLoc(),
278  "LLVM IR generation of compound statement ('{}')");
279 
280  // Keep track of the current cleanup stack depth, including debug scopes.
281  LexicalScope Scope(*this, S.getSourceRange());
282 
283  return EmitCompoundStmtWithoutScope(S, GetLast, AggSlot);
284 }
285 
288  bool GetLast,
289  AggValueSlot AggSlot) {
290 
292  E = S.body_end()-GetLast; I != E; ++I)
293  EmitStmt(*I);
294 
295  llvm::Value *RetAlloca = nullptr;
296  if (GetLast) {
297  // We have to special case labels here. They are statements, but when put
298  // at the end of a statement expression, they yield the value of their
299  // subexpression. Handle this by walking through all labels we encounter,
300  // emitting them before we evaluate the subexpr.
301  const Stmt *LastStmt = S.body_back();
302  while (const LabelStmt *LS = dyn_cast<LabelStmt>(LastStmt)) {
303  EmitLabel(LS->getDecl());
304  LastStmt = LS->getSubStmt();
305  }
306 
308 
309  QualType ExprTy = cast<Expr>(LastStmt)->getType();
310  if (hasAggregateEvaluationKind(ExprTy)) {
311  EmitAggExpr(cast<Expr>(LastStmt), AggSlot);
312  } else {
313  // We can't return an RValue here because there might be cleanups at
314  // the end of the StmtExpr. Because of that, we have to emit the result
315  // here into a temporary alloca.
316  RetAlloca = CreateMemTemp(ExprTy);
317  EmitAnyExprToMem(cast<Expr>(LastStmt), RetAlloca, Qualifiers(),
318  /*IsInit*/false);
319  }
320 
321  }
322 
323  return RetAlloca;
324 }
325 
326 void CodeGenFunction::SimplifyForwardingBlocks(llvm::BasicBlock *BB) {
327  llvm::BranchInst *BI = dyn_cast<llvm::BranchInst>(BB->getTerminator());
328 
329  // If there is a cleanup stack, then we it isn't worth trying to
330  // simplify this block (we would need to remove it from the scope map
331  // and cleanup entry).
332  if (!EHStack.empty())
333  return;
334 
335  // Can only simplify direct branches.
336  if (!BI || !BI->isUnconditional())
337  return;
338 
339  // Can only simplify empty blocks.
340  if (BI != BB->begin())
341  return;
342 
343  BB->replaceAllUsesWith(BI->getSuccessor(0));
344  BI->eraseFromParent();
345  BB->eraseFromParent();
346 }
347 
348 void CodeGenFunction::EmitBlock(llvm::BasicBlock *BB, bool IsFinished) {
349  llvm::BasicBlock *CurBB = Builder.GetInsertBlock();
350 
351  // Fall out of the current block (if necessary).
352  EmitBranch(BB);
353 
354  if (IsFinished && BB->use_empty()) {
355  delete BB;
356  return;
357  }
358 
359  // Place the block after the current block, if possible, or else at
360  // the end of the function.
361  if (CurBB && CurBB->getParent())
362  CurFn->getBasicBlockList().insertAfter(CurBB, BB);
363  else
364  CurFn->getBasicBlockList().push_back(BB);
365  Builder.SetInsertPoint(BB);
366 }
367 
368 void CodeGenFunction::EmitBranch(llvm::BasicBlock *Target) {
369  // Emit a branch from the current block to the target one if this
370  // was a real block. If this was just a fall-through block after a
371  // terminator, don't emit it.
372  llvm::BasicBlock *CurBB = Builder.GetInsertBlock();
373 
374  if (!CurBB || CurBB->getTerminator()) {
375  // If there is no insert point or the previous block is already
376  // terminated, don't touch it.
377  } else {
378  // Otherwise, create a fall-through branch.
379  Builder.CreateBr(Target);
380  }
381 
382  Builder.ClearInsertionPoint();
383 }
384 
385 void CodeGenFunction::EmitBlockAfterUses(llvm::BasicBlock *block) {
386  bool inserted = false;
387  for (llvm::User *u : block->users()) {
388  if (llvm::Instruction *insn = dyn_cast<llvm::Instruction>(u)) {
389  CurFn->getBasicBlockList().insertAfter(insn->getParent(), block);
390  inserted = true;
391  break;
392  }
393  }
394 
395  if (!inserted)
396  CurFn->getBasicBlockList().push_back(block);
397 
398  Builder.SetInsertPoint(block);
399 }
400 
403  JumpDest &Dest = LabelMap[D];
404  if (Dest.isValid()) return Dest;
405 
406  // Create, but don't insert, the new block.
407  Dest = JumpDest(createBasicBlock(D->getName()),
410  return Dest;
411 }
412 
414  // Add this label to the current lexical scope if we're within any
415  // normal cleanups. Jumps "in" to this label --- when permitted by
416  // the language --- may need to be routed around such cleanups.
417  if (EHStack.hasNormalCleanups() && CurLexicalScope)
418  CurLexicalScope->addLabel(D);
419 
420  JumpDest &Dest = LabelMap[D];
421 
422  // If we didn't need a forward reference to this label, just go
423  // ahead and create a destination at the current scope.
424  if (!Dest.isValid()) {
425  Dest = getJumpDestInCurrentScope(D->getName());
426 
427  // Otherwise, we need to give this label a target depth and remove
428  // it from the branch-fixups list.
429  } else {
430  assert(!Dest.getScopeDepth().isValid() && "already emitted label!");
433  }
434 
435  EmitBlock(Dest.getBlock());
437 }
438 
439 /// Change the cleanup scope of the labels in this lexical scope to
440 /// match the scope of the enclosing context.
442  assert(!Labels.empty());
443  EHScopeStack::stable_iterator innermostScope
445 
446  // Change the scope depth of all the labels.
448  i = Labels.begin(), e = Labels.end(); i != e; ++i) {
449  assert(CGF.LabelMap.count(*i));
450  JumpDest &dest = CGF.LabelMap.find(*i)->second;
451  assert(dest.getScopeDepth().isValid());
452  assert(innermostScope.encloses(dest.getScopeDepth()));
453  dest.setScopeDepth(innermostScope);
454  }
455 
456  // Reparent the labels if the new scope also has cleanups.
457  if (innermostScope != EHScopeStack::stable_end() && ParentScope) {
458  ParentScope->Labels.append(Labels.begin(), Labels.end());
459  }
460 }
461 
462 
464  EmitLabel(S.getDecl());
465  EmitStmt(S.getSubStmt());
466 }
467 
469  const Stmt *SubStmt = S.getSubStmt();
470  switch (SubStmt->getStmtClass()) {
471  case Stmt::DoStmtClass:
472  EmitDoStmt(cast<DoStmt>(*SubStmt), S.getAttrs());
473  break;
474  case Stmt::ForStmtClass:
475  EmitForStmt(cast<ForStmt>(*SubStmt), S.getAttrs());
476  break;
477  case Stmt::WhileStmtClass:
478  EmitWhileStmt(cast<WhileStmt>(*SubStmt), S.getAttrs());
479  break;
480  case Stmt::CXXForRangeStmtClass:
481  EmitCXXForRangeStmt(cast<CXXForRangeStmt>(*SubStmt), S.getAttrs());
482  break;
483  default:
484  EmitStmt(SubStmt);
485  }
486 }
487 
489  // If this code is reachable then emit a stop point (if generating
490  // debug info). We have to do this ourselves because we are on the
491  // "simple" statement path.
492  if (HaveInsertPoint())
493  EmitStopPoint(&S);
494 
496 }
497 
498 
500  if (const LabelDecl *Target = S.getConstantTarget()) {
502  return;
503  }
504 
505  // Ensure that we have an i8* for our PHI node.
506  llvm::Value *V = Builder.CreateBitCast(EmitScalarExpr(S.getTarget()),
507  Int8PtrTy, "addr");
508  llvm::BasicBlock *CurBB = Builder.GetInsertBlock();
509 
510  // Get the basic block for the indirect goto.
511  llvm::BasicBlock *IndGotoBB = GetIndirectGotoBlock();
512 
513  // The first instruction in the block has to be the PHI for the switch dest,
514  // add an entry for this branch.
515  cast<llvm::PHINode>(IndGotoBB->begin())->addIncoming(V, CurBB);
516 
517  EmitBranch(IndGotoBB);
518 }
519 
521  // C99 6.8.4.1: The first substatement is executed if the expression compares
522  // unequal to 0. The condition must be a scalar type.
523  LexicalScope ConditionScope(*this, S.getCond()->getSourceRange());
524 
525  if (S.getConditionVariable())
527 
528  // If the condition constant folds and can be elided, try to avoid emitting
529  // the condition and the dead arm of the if/else.
530  bool CondConstant;
531  if (ConstantFoldsToSimpleInteger(S.getCond(), CondConstant)) {
532  // Figure out which block (then or else) is executed.
533  const Stmt *Executed = S.getThen();
534  const Stmt *Skipped = S.getElse();
535  if (!CondConstant) // Condition false?
536  std::swap(Executed, Skipped);
537 
538  // If the skipped block has no labels in it, just emit the executed block.
539  // This avoids emitting dead code and simplifies the CFG substantially.
540  if (!ContainsLabel(Skipped)) {
541  if (CondConstant)
543  if (Executed) {
544  RunCleanupsScope ExecutedScope(*this);
545  EmitStmt(Executed);
546  }
547  return;
548  }
549  }
550 
551  // Otherwise, the condition did not fold, or we couldn't elide it. Just emit
552  // the conditional branch.
553  llvm::BasicBlock *ThenBlock = createBasicBlock("if.then");
554  llvm::BasicBlock *ContBlock = createBasicBlock("if.end");
555  llvm::BasicBlock *ElseBlock = ContBlock;
556  if (S.getElse())
557  ElseBlock = createBasicBlock("if.else");
558 
559  EmitBranchOnBoolExpr(S.getCond(), ThenBlock, ElseBlock,
560  getProfileCount(S.getThen()));
561 
562  // Emit the 'then' code.
563  EmitBlock(ThenBlock);
565  {
566  RunCleanupsScope ThenScope(*this);
567  EmitStmt(S.getThen());
568  }
569  EmitBranch(ContBlock);
570 
571  // Emit the 'else' code if present.
572  if (const Stmt *Else = S.getElse()) {
573  {
574  // There is no need to emit line number for an unconditional branch.
575  auto NL = ApplyDebugLocation::CreateEmpty(*this);
576  EmitBlock(ElseBlock);
577  }
578  {
579  RunCleanupsScope ElseScope(*this);
580  EmitStmt(Else);
581  }
582  {
583  // There is no need to emit line number for an unconditional branch.
584  auto NL = ApplyDebugLocation::CreateEmpty(*this);
585  EmitBranch(ContBlock);
586  }
587  }
588 
589  // Emit the continuation block for code after the if.
590  EmitBlock(ContBlock, true);
591 }
592 
594  llvm::BranchInst *CondBr,
595  ArrayRef<const Attr *> Attrs) {
596  // Return if there are no hints.
597  if (Attrs.empty())
598  return;
599 
600  // Add vectorize and unroll hints to the metadata on the conditional branch.
601  //
602  // FIXME: Should this really start with a size of 1?
604  for (const auto *Attr : Attrs) {
605  const LoopHintAttr *LH = dyn_cast<LoopHintAttr>(Attr);
606 
607  // Skip non loop hint attributes
608  if (!LH)
609  continue;
610 
611  LoopHintAttr::OptionType Option = LH->getOption();
612  LoopHintAttr::LoopHintState State = LH->getState();
613  const char *MetadataName;
614  switch (Option) {
615  case LoopHintAttr::Vectorize:
616  case LoopHintAttr::VectorizeWidth:
617  MetadataName = "llvm.loop.vectorize.width";
618  break;
619  case LoopHintAttr::Interleave:
620  case LoopHintAttr::InterleaveCount:
621  MetadataName = "llvm.loop.interleave.count";
622  break;
623  case LoopHintAttr::Unroll:
624  // With the unroll loop hint, a non-zero value indicates full unrolling.
625  MetadataName = State == LoopHintAttr::Disable ? "llvm.loop.unroll.disable"
626  : "llvm.loop.unroll.full";
627  break;
628  case LoopHintAttr::UnrollCount:
629  MetadataName = "llvm.loop.unroll.count";
630  break;
631  }
632 
633  Expr *ValueExpr = LH->getValue();
634  int ValueInt = 1;
635  if (ValueExpr) {
636  llvm::APSInt ValueAPS =
637  ValueExpr->EvaluateKnownConstInt(CGM.getContext());
638  ValueInt = static_cast<int>(ValueAPS.getSExtValue());
639  }
640 
641  llvm::Constant *Value;
642  llvm::MDString *Name;
643  switch (Option) {
644  case LoopHintAttr::Vectorize:
645  case LoopHintAttr::Interleave:
646  if (State != LoopHintAttr::Disable) {
647  // FIXME: In the future I will modifiy the behavior of the metadata
648  // so we can enable/disable vectorization and interleaving separately.
649  Name = llvm::MDString::get(Context, "llvm.loop.vectorize.enable");
650  Value = Builder.getTrue();
651  break;
652  }
653  // Vectorization/interleaving is disabled, set width/count to 1.
654  ValueInt = 1;
655  // Fallthrough.
656  case LoopHintAttr::VectorizeWidth:
657  case LoopHintAttr::InterleaveCount:
658  case LoopHintAttr::UnrollCount:
659  Name = llvm::MDString::get(Context, MetadataName);
660  Value = llvm::ConstantInt::get(Int32Ty, ValueInt);
661  break;
662  case LoopHintAttr::Unroll:
663  Name = llvm::MDString::get(Context, MetadataName);
664  Value = nullptr;
665  break;
666  }
667 
669  OpValues.push_back(Name);
670  if (Value)
671  OpValues.push_back(llvm::ConstantAsMetadata::get(Value));
672 
673  // Set or overwrite metadata indicated by Name.
674  Metadata.push_back(llvm::MDNode::get(Context, OpValues));
675  }
676 
677  // FIXME: This condition is never false. Should it be an assert?
678  if (!Metadata.empty()) {
679  // Add llvm.loop MDNode to CondBr.
680  llvm::MDNode *LoopID = llvm::MDNode::get(Context, Metadata);
681  LoopID->replaceOperandWith(0, LoopID); // First op points to itself.
682 
683  CondBr->setMetadata("llvm.loop", LoopID);
684  }
685 }
686 
688  ArrayRef<const Attr *> WhileAttrs) {
689  // Emit the header for the loop, which will also become
690  // the continue target.
691  JumpDest LoopHeader = getJumpDestInCurrentScope("while.cond");
692  EmitBlock(LoopHeader.getBlock());
693 
694  LoopStack.push(LoopHeader.getBlock(), WhileAttrs);
695 
696  // Create an exit block for when the condition fails, which will
697  // also become the break target.
698  JumpDest LoopExit = getJumpDestInCurrentScope("while.end");
699 
700  // Store the blocks to use for break and continue.
701  BreakContinueStack.push_back(BreakContinue(LoopExit, LoopHeader));
702 
703  // C++ [stmt.while]p2:
704  // When the condition of a while statement is a declaration, the
705  // scope of the variable that is declared extends from its point
706  // of declaration (3.3.2) to the end of the while statement.
707  // [...]
708  // The object created in a condition is destroyed and created
709  // with each iteration of the loop.
710  RunCleanupsScope ConditionScope(*this);
711 
712  if (S.getConditionVariable())
714 
715  // Evaluate the conditional in the while header. C99 6.8.5.1: The
716  // evaluation of the controlling expression takes place before each
717  // execution of the loop body.
718  llvm::Value *BoolCondVal = EvaluateExprAsBool(S.getCond());
719 
720  // while(1) is common, avoid extra exit blocks. Be sure
721  // to correctly handle break/continue though.
722  bool EmitBoolCondBranch = true;
723  if (llvm::ConstantInt *C = dyn_cast<llvm::ConstantInt>(BoolCondVal))
724  if (C->isOne())
725  EmitBoolCondBranch = false;
726 
727  // As long as the condition is true, go to the loop body.
728  llvm::BasicBlock *LoopBody = createBasicBlock("while.body");
729  if (EmitBoolCondBranch) {
730  llvm::BasicBlock *ExitBlock = LoopExit.getBlock();
731  if (ConditionScope.requiresCleanups())
732  ExitBlock = createBasicBlock("while.exit");
733  llvm::BranchInst *CondBr = Builder.CreateCondBr(
734  BoolCondVal, LoopBody, ExitBlock,
735  createProfileWeightsForLoop(S.getCond(), getProfileCount(S.getBody())));
736 
737  if (ExitBlock != LoopExit.getBlock()) {
738  EmitBlock(ExitBlock);
739  EmitBranchThroughCleanup(LoopExit);
740  }
741 
742  // Attach metadata to loop body conditional branch.
743  EmitCondBrHints(LoopBody->getContext(), CondBr, WhileAttrs);
744  }
745 
746  // Emit the loop body. We have to emit this in a cleanup scope
747  // because it might be a singleton DeclStmt.
748  {
749  RunCleanupsScope BodyScope(*this);
750  EmitBlock(LoopBody);
752  EmitStmt(S.getBody());
753  }
754 
755  BreakContinueStack.pop_back();
756 
757  // Immediately force cleanup.
758  ConditionScope.ForceCleanup();
759 
760  EmitStopPoint(&S);
761  // Branch to the loop header again.
762  EmitBranch(LoopHeader.getBlock());
763 
764  LoopStack.pop();
765 
766  // Emit the exit block.
767  EmitBlock(LoopExit.getBlock(), true);
768 
769  // The LoopHeader typically is just a branch if we skipped emitting
770  // a branch, try to erase it.
771  if (!EmitBoolCondBranch)
772  SimplifyForwardingBlocks(LoopHeader.getBlock());
773 }
774 
776  ArrayRef<const Attr *> DoAttrs) {
777  JumpDest LoopExit = getJumpDestInCurrentScope("do.end");
778  JumpDest LoopCond = getJumpDestInCurrentScope("do.cond");
779 
780  uint64_t ParentCount = getCurrentProfileCount();
781 
782  // Store the blocks to use for break and continue.
783  BreakContinueStack.push_back(BreakContinue(LoopExit, LoopCond));
784 
785  // Emit the body of the loop.
786  llvm::BasicBlock *LoopBody = createBasicBlock("do.body");
787 
788  LoopStack.push(LoopBody, DoAttrs);
789 
790  EmitBlockWithFallThrough(LoopBody, &S);
791  {
792  RunCleanupsScope BodyScope(*this);
793  EmitStmt(S.getBody());
794  }
795 
796  EmitBlock(LoopCond.getBlock());
797 
798  // C99 6.8.5.2: "The evaluation of the controlling expression takes place
799  // after each execution of the loop body."
800 
801  // Evaluate the conditional in the while header.
802  // C99 6.8.5p2/p4: The first substatement is executed if the expression
803  // compares unequal to 0. The condition must be a scalar type.
804  llvm::Value *BoolCondVal = EvaluateExprAsBool(S.getCond());
805 
806  BreakContinueStack.pop_back();
807 
808  // "do {} while (0)" is common in macros, avoid extra blocks. Be sure
809  // to correctly handle break/continue though.
810  bool EmitBoolCondBranch = true;
811  if (llvm::ConstantInt *C = dyn_cast<llvm::ConstantInt>(BoolCondVal))
812  if (C->isZero())
813  EmitBoolCondBranch = false;
814 
815  // As long as the condition is true, iterate the loop.
816  if (EmitBoolCondBranch) {
817  uint64_t BackedgeCount = getProfileCount(S.getBody()) - ParentCount;
818  llvm::BranchInst *CondBr = Builder.CreateCondBr(
819  BoolCondVal, LoopBody, LoopExit.getBlock(),
820  createProfileWeightsForLoop(S.getCond(), BackedgeCount));
821 
822  // Attach metadata to loop body conditional branch.
823  EmitCondBrHints(LoopBody->getContext(), CondBr, DoAttrs);
824  }
825 
826  LoopStack.pop();
827 
828  // Emit the exit block.
829  EmitBlock(LoopExit.getBlock());
830 
831  // The DoCond block typically is just a branch if we skipped
832  // emitting a branch, try to erase it.
833  if (!EmitBoolCondBranch)
835 }
836 
838  ArrayRef<const Attr *> ForAttrs) {
839  JumpDest LoopExit = getJumpDestInCurrentScope("for.end");
840 
841  LexicalScope ForScope(*this, S.getSourceRange());
842 
843  // Evaluate the first part before the loop.
844  if (S.getInit())
845  EmitStmt(S.getInit());
846 
847  // Start the loop with a block that tests the condition.
848  // If there's an increment, the continue scope will be overwritten
849  // later.
850  JumpDest Continue = getJumpDestInCurrentScope("for.cond");
851  llvm::BasicBlock *CondBlock = Continue.getBlock();
852  EmitBlock(CondBlock);
853 
854  LoopStack.push(CondBlock, ForAttrs);
855 
856  // If the for loop doesn't have an increment we can just use the
857  // condition as the continue block. Otherwise we'll need to create
858  // a block for it (in the current scope, i.e. in the scope of the
859  // condition), and that we will become our continue block.
860  if (S.getInc())
861  Continue = getJumpDestInCurrentScope("for.inc");
862 
863  // Store the blocks to use for break and continue.
864  BreakContinueStack.push_back(BreakContinue(LoopExit, Continue));
865 
866  // Create a cleanup scope for the condition variable cleanups.
867  LexicalScope ConditionScope(*this, S.getSourceRange());
868 
869  if (S.getCond()) {
870  // If the for statement has a condition scope, emit the local variable
871  // declaration.
872  if (S.getConditionVariable()) {
874  }
875 
876  llvm::BasicBlock *ExitBlock = LoopExit.getBlock();
877  // If there are any cleanups between here and the loop-exit scope,
878  // create a block to stage a loop exit along.
879  if (ForScope.requiresCleanups())
880  ExitBlock = createBasicBlock("for.cond.cleanup");
881 
882  // As long as the condition is true, iterate the loop.
883  llvm::BasicBlock *ForBody = createBasicBlock("for.body");
884 
885  // C99 6.8.5p2/p4: The first substatement is executed if the expression
886  // compares unequal to 0. The condition must be a scalar type.
887  llvm::Value *BoolCondVal = EvaluateExprAsBool(S.getCond());
888  llvm::BranchInst *CondBr = Builder.CreateCondBr(
889  BoolCondVal, ForBody, ExitBlock,
890  createProfileWeightsForLoop(S.getCond(), getProfileCount(S.getBody())));
891 
892  // Attach metadata to loop body conditional branch.
893  EmitCondBrHints(ForBody->getContext(), CondBr, ForAttrs);
894 
895  if (ExitBlock != LoopExit.getBlock()) {
896  EmitBlock(ExitBlock);
897  EmitBranchThroughCleanup(LoopExit);
898  }
899 
900  EmitBlock(ForBody);
901  } else {
902  // Treat it as a non-zero constant. Don't even create a new block for the
903  // body, just fall into it.
904  }
906 
907  {
908  // Create a separate cleanup scope for the body, in case it is not
909  // a compound statement.
910  RunCleanupsScope BodyScope(*this);
911  EmitStmt(S.getBody());
912  }
913 
914  // If there is an increment, emit it next.
915  if (S.getInc()) {
916  EmitBlock(Continue.getBlock());
917  EmitStmt(S.getInc());
918  }
919 
920  BreakContinueStack.pop_back();
921 
922  ConditionScope.ForceCleanup();
923 
924  EmitStopPoint(&S);
925  EmitBranch(CondBlock);
926 
927  ForScope.ForceCleanup();
928 
929  LoopStack.pop();
930 
931  // Emit the fall-through block.
932  EmitBlock(LoopExit.getBlock(), true);
933 }
934 
935 void
937  ArrayRef<const Attr *> ForAttrs) {
938  JumpDest LoopExit = getJumpDestInCurrentScope("for.end");
939 
940  LexicalScope ForScope(*this, S.getSourceRange());
941 
942  // Evaluate the first pieces before the loop.
943  EmitStmt(S.getRangeStmt());
945 
946  // Start the loop with a block that tests the condition.
947  // If there's an increment, the continue scope will be overwritten
948  // later.
949  llvm::BasicBlock *CondBlock = createBasicBlock("for.cond");
950  EmitBlock(CondBlock);
951 
952  LoopStack.push(CondBlock, ForAttrs);
953 
954  // If there are any cleanups between here and the loop-exit scope,
955  // create a block to stage a loop exit along.
956  llvm::BasicBlock *ExitBlock = LoopExit.getBlock();
957  if (ForScope.requiresCleanups())
958  ExitBlock = createBasicBlock("for.cond.cleanup");
959 
960  // The loop body, consisting of the specified body and the loop variable.
961  llvm::BasicBlock *ForBody = createBasicBlock("for.body");
962 
963  // The body is executed if the expression, contextually converted
964  // to bool, is true.
965  llvm::Value *BoolCondVal = EvaluateExprAsBool(S.getCond());
966  llvm::BranchInst *CondBr = Builder.CreateCondBr(
967  BoolCondVal, ForBody, ExitBlock,
968  createProfileWeightsForLoop(S.getCond(), getProfileCount(S.getBody())));
969 
970  // Attach metadata to loop body conditional branch.
971  EmitCondBrHints(ForBody->getContext(), CondBr, ForAttrs);
972 
973  if (ExitBlock != LoopExit.getBlock()) {
974  EmitBlock(ExitBlock);
975  EmitBranchThroughCleanup(LoopExit);
976  }
977 
978  EmitBlock(ForBody);
980 
981  // Create a block for the increment. In case of a 'continue', we jump there.
982  JumpDest Continue = getJumpDestInCurrentScope("for.inc");
983 
984  // Store the blocks to use for break and continue.
985  BreakContinueStack.push_back(BreakContinue(LoopExit, Continue));
986 
987  {
988  // Create a separate cleanup scope for the loop variable and body.
989  LexicalScope BodyScope(*this, S.getSourceRange());
991  EmitStmt(S.getBody());
992  }
993 
994  EmitStopPoint(&S);
995  // If there is an increment, emit it next.
996  EmitBlock(Continue.getBlock());
997  EmitStmt(S.getInc());
998 
999  BreakContinueStack.pop_back();
1000 
1001  EmitBranch(CondBlock);
1002 
1003  ForScope.ForceCleanup();
1004 
1005  LoopStack.pop();
1006 
1007  // Emit the fall-through block.
1008  EmitBlock(LoopExit.getBlock(), true);
1009 }
1010 
1011 void CodeGenFunction::EmitReturnOfRValue(RValue RV, QualType Ty) {
1012  if (RV.isScalar()) {
1013  Builder.CreateStore(RV.getScalarVal(), ReturnValue);
1014  } else if (RV.isAggregate()) {
1016  } else {
1019  /*init*/ true);
1020  }
1022 }
1023 
1024 /// EmitReturnStmt - Note that due to GCC extensions, this can have an operand
1025 /// if the function returns void, or may be missing one if the function returns
1026 /// non-void. Fun stuff :).
1028  // Returning from an outlined SEH helper is UB, and we already warn on it.
1029  if (IsOutlinedSEHHelper) {
1030  Builder.CreateUnreachable();
1031  Builder.ClearInsertionPoint();
1032  }
1033 
1034  // Emit the result value, even if unused, to evalute the side effects.
1035  const Expr *RV = S.getRetValue();
1036 
1037  // Treat block literals in a return expression as if they appeared
1038  // in their own scope. This permits a small, easily-implemented
1039  // exception to our over-conservative rules about not jumping to
1040  // statements following block literals with non-trivial cleanups.
1041  RunCleanupsScope cleanupScope(*this);
1042  if (const ExprWithCleanups *cleanups =
1043  dyn_cast_or_null<ExprWithCleanups>(RV)) {
1044  enterFullExpression(cleanups);
1045  RV = cleanups->getSubExpr();
1046  }
1047 
1048  // FIXME: Clean this up by using an LValue for ReturnTemp,
1049  // EmitStoreThroughLValue, and EmitAnyExpr.
1050  if (getLangOpts().ElideConstructors &&
1052  // Apply the named return value optimization for this return statement,
1053  // which means doing nothing: the appropriate result has already been
1054  // constructed into the NRVO variable.
1055 
1056  // If there is an NRVO flag for this variable, set it to 1 into indicate
1057  // that the cleanup code should not destroy the variable.
1058  if (llvm::Value *NRVOFlag = NRVOFlags[S.getNRVOCandidate()])
1059  Builder.CreateStore(Builder.getTrue(), NRVOFlag);
1060  } else if (!ReturnValue || (RV && RV->getType()->isVoidType())) {
1061  // Make sure not to return anything, but evaluate the expression
1062  // for side effects.
1063  if (RV)
1064  EmitAnyExpr(RV);
1065  } else if (!RV) {
1066  // Do nothing (return value is left uninitialized)
1067  } else if (FnRetTy->isReferenceType()) {
1068  // If this function returns a reference, take the address of the expression
1069  // rather than the value.
1071  Builder.CreateStore(Result.getScalarVal(), ReturnValue);
1072  } else {
1073  switch (getEvaluationKind(RV->getType())) {
1074  case TEK_Scalar:
1075  Builder.CreateStore(EmitScalarExpr(RV), ReturnValue);
1076  break;
1077  case TEK_Complex:
1080  /*isInit*/ true);
1081  break;
1082  case TEK_Aggregate: {
1083  CharUnits Alignment = getContext().getTypeAlignInChars(RV->getType());
1085  Qualifiers(),
1089  break;
1090  }
1091  }
1092  }
1093 
1094  ++NumReturnExprs;
1095  if (!RV || RV->isEvaluatable(getContext()))
1096  ++NumSimpleReturnExprs;
1097 
1098  cleanupScope.ForceCleanup();
1100 }
1101 
1103  // As long as debug info is modeled with instructions, we have to ensure we
1104  // have a place to insert here and write the stop point here.
1105  if (HaveInsertPoint())
1106  EmitStopPoint(&S);
1107 
1108  for (const auto *I : S.decls())
1109  EmitDecl(*I);
1110 }
1111 
1113  assert(!BreakContinueStack.empty() && "break stmt not in a loop or switch!");
1114 
1115  // If this code is reachable then emit a stop point (if generating
1116  // debug info). We have to do this ourselves because we are on the
1117  // "simple" statement path.
1118  if (HaveInsertPoint())
1119  EmitStopPoint(&S);
1120 
1121  EmitBranchThroughCleanup(BreakContinueStack.back().BreakBlock);
1122 }
1123 
1125  assert(!BreakContinueStack.empty() && "continue stmt not in a loop!");
1126 
1127  // If this code is reachable then emit a stop point (if generating
1128  // debug info). We have to do this ourselves because we are on the
1129  // "simple" statement path.
1130  if (HaveInsertPoint())
1131  EmitStopPoint(&S);
1132 
1133  EmitBranchThroughCleanup(BreakContinueStack.back().ContinueBlock);
1134 }
1135 
1136 /// EmitCaseStmtRange - If case statement range is not too big then
1137 /// add multiple cases to switch instruction, one for each value within
1138 /// the range. If range is too big then emit "if" condition check.
1140  assert(S.getRHS() && "Expected RHS value in CaseStmt");
1141 
1142  llvm::APSInt LHS = S.getLHS()->EvaluateKnownConstInt(getContext());
1143  llvm::APSInt RHS = S.getRHS()->EvaluateKnownConstInt(getContext());
1144 
1145  // Emit the code for this case. We do this first to make sure it is
1146  // properly chained from our predecessor before generating the
1147  // switch machinery to enter this block.
1148  llvm::BasicBlock *CaseDest = createBasicBlock("sw.bb");
1149  EmitBlockWithFallThrough(CaseDest, &S);
1150  EmitStmt(S.getSubStmt());
1151 
1152  // If range is empty, do nothing.
1153  if (LHS.isSigned() ? RHS.slt(LHS) : RHS.ult(LHS))
1154  return;
1155 
1156  llvm::APInt Range = RHS - LHS;
1157  // FIXME: parameters such as this should not be hardcoded.
1158  if (Range.ult(llvm::APInt(Range.getBitWidth(), 64))) {
1159  // Range is small enough to add multiple switch instruction cases.
1160  uint64_t Total = getProfileCount(&S);
1161  unsigned NCases = Range.getZExtValue() + 1;
1162  // We only have one region counter for the entire set of cases here, so we
1163  // need to divide the weights evenly between the generated cases, ensuring
1164  // that the total weight is preserved. E.g., a weight of 5 over three cases
1165  // will be distributed as weights of 2, 2, and 1.
1166  uint64_t Weight = Total / NCases, Rem = Total % NCases;
1167  for (unsigned I = 0; I != NCases; ++I) {
1168  if (SwitchWeights)
1169  SwitchWeights->push_back(Weight + (Rem ? 1 : 0));
1170  if (Rem)
1171  Rem--;
1172  SwitchInsn->addCase(Builder.getInt(LHS), CaseDest);
1173  LHS++;
1174  }
1175  return;
1176  }
1177 
1178  // The range is too big. Emit "if" condition into a new block,
1179  // making sure to save and restore the current insertion point.
1180  llvm::BasicBlock *RestoreBB = Builder.GetInsertBlock();
1181 
1182  // Push this test onto the chain of range checks (which terminates
1183  // in the default basic block). The switch's default will be changed
1184  // to the top of this chain after switch emission is complete.
1185  llvm::BasicBlock *FalseDest = CaseRangeBlock;
1186  CaseRangeBlock = createBasicBlock("sw.caserange");
1187 
1188  CurFn->getBasicBlockList().push_back(CaseRangeBlock);
1189  Builder.SetInsertPoint(CaseRangeBlock);
1190 
1191  // Emit range check.
1192  llvm::Value *Diff =
1193  Builder.CreateSub(SwitchInsn->getCondition(), Builder.getInt(LHS));
1194  llvm::Value *Cond =
1195  Builder.CreateICmpULE(Diff, Builder.getInt(Range), "inbounds");
1196 
1197  llvm::MDNode *Weights = nullptr;
1198  if (SwitchWeights) {
1199  uint64_t ThisCount = getProfileCount(&S);
1200  uint64_t DefaultCount = (*SwitchWeights)[0];
1201  Weights = createProfileWeights(ThisCount, DefaultCount);
1202 
1203  // Since we're chaining the switch default through each large case range, we
1204  // need to update the weight for the default, ie, the first case, to include
1205  // this case.
1206  (*SwitchWeights)[0] += ThisCount;
1207  }
1208  Builder.CreateCondBr(Cond, CaseDest, FalseDest, Weights);
1209 
1210  // Restore the appropriate insertion point.
1211  if (RestoreBB)
1212  Builder.SetInsertPoint(RestoreBB);
1213  else
1214  Builder.ClearInsertionPoint();
1215 }
1216 
1218  // If there is no enclosing switch instance that we're aware of, then this
1219  // case statement and its block can be elided. This situation only happens
1220  // when we've constant-folded the switch, are emitting the constant case,
1221  // and part of the constant case includes another case statement. For
1222  // instance: switch (4) { case 4: do { case 5: } while (1); }
1223  if (!SwitchInsn) {
1224  EmitStmt(S.getSubStmt());
1225  return;
1226  }
1227 
1228  // Handle case ranges.
1229  if (S.getRHS()) {
1230  EmitCaseStmtRange(S);
1231  return;
1232  }
1233 
1234  llvm::ConstantInt *CaseVal =
1236 
1237  // If the body of the case is just a 'break', try to not emit an empty block.
1238  // If we're profiling or we're not optimizing, leave the block in for better
1239  // debug and coverage analysis.
1240  if (!CGM.getCodeGenOpts().ProfileInstrGenerate &&
1241  CGM.getCodeGenOpts().OptimizationLevel > 0 &&
1242  isa<BreakStmt>(S.getSubStmt())) {
1243  JumpDest Block = BreakContinueStack.back().BreakBlock;
1244 
1245  // Only do this optimization if there are no cleanups that need emitting.
1246  if (isObviouslyBranchWithoutCleanups(Block)) {
1247  if (SwitchWeights)
1248  SwitchWeights->push_back(getProfileCount(&S));
1249  SwitchInsn->addCase(CaseVal, Block.getBlock());
1250 
1251  // If there was a fallthrough into this case, make sure to redirect it to
1252  // the end of the switch as well.
1253  if (Builder.GetInsertBlock()) {
1254  Builder.CreateBr(Block.getBlock());
1255  Builder.ClearInsertionPoint();
1256  }
1257  return;
1258  }
1259  }
1260 
1261  llvm::BasicBlock *CaseDest = createBasicBlock("sw.bb");
1262  EmitBlockWithFallThrough(CaseDest, &S);
1263  if (SwitchWeights)
1264  SwitchWeights->push_back(getProfileCount(&S));
1265  SwitchInsn->addCase(CaseVal, CaseDest);
1266 
1267  // Recursively emitting the statement is acceptable, but is not wonderful for
1268  // code where we have many case statements nested together, i.e.:
1269  // case 1:
1270  // case 2:
1271  // case 3: etc.
1272  // Handling this recursively will create a new block for each case statement
1273  // that falls through to the next case which is IR intensive. It also causes
1274  // deep recursion which can run into stack depth limitations. Handle
1275  // sequential non-range case statements specially.
1276  const CaseStmt *CurCase = &S;
1277  const CaseStmt *NextCase = dyn_cast<CaseStmt>(S.getSubStmt());
1278 
1279  // Otherwise, iteratively add consecutive cases to this switch stmt.
1280  while (NextCase && NextCase->getRHS() == nullptr) {
1281  CurCase = NextCase;
1282  llvm::ConstantInt *CaseVal =
1283  Builder.getInt(CurCase->getLHS()->EvaluateKnownConstInt(getContext()));
1284 
1285  if (SwitchWeights)
1286  SwitchWeights->push_back(getProfileCount(NextCase));
1287  if (CGM.getCodeGenOpts().ProfileInstrGenerate) {
1288  CaseDest = createBasicBlock("sw.bb");
1289  EmitBlockWithFallThrough(CaseDest, &S);
1290  }
1291 
1292  SwitchInsn->addCase(CaseVal, CaseDest);
1293  NextCase = dyn_cast<CaseStmt>(CurCase->getSubStmt());
1294  }
1295 
1296  // Normal default recursion for non-cases.
1297  EmitStmt(CurCase->getSubStmt());
1298 }
1299 
1301  llvm::BasicBlock *DefaultBlock = SwitchInsn->getDefaultDest();
1302  assert(DefaultBlock->empty() &&
1303  "EmitDefaultStmt: Default block already defined?");
1304 
1305  EmitBlockWithFallThrough(DefaultBlock, &S);
1306 
1307  EmitStmt(S.getSubStmt());
1308 }
1309 
1310 /// CollectStatementsForCase - Given the body of a 'switch' statement and a
1311 /// constant value that is being switched on, see if we can dead code eliminate
1312 /// the body of the switch to a simple series of statements to emit. Basically,
1313 /// on a switch (5) we want to find these statements:
1314 /// case 5:
1315 /// printf(...); <--
1316 /// ++i; <--
1317 /// break;
1318 ///
1319 /// and add them to the ResultStmts vector. If it is unsafe to do this
1320 /// transformation (for example, one of the elided statements contains a label
1321 /// that might be jumped to), return CSFC_Failure. If we handled it and 'S'
1322 /// should include statements after it (e.g. the printf() line is a substmt of
1323 /// the case) then return CSFC_FallThrough. If we handled it and found a break
1324 /// statement, then return CSFC_Success.
1325 ///
1326 /// If Case is non-null, then we are looking for the specified case, checking
1327 /// that nothing we jump over contains labels. If Case is null, then we found
1328 /// the case and are looking for the break.
1329 ///
1330 /// If the recursive walk actually finds our Case, then we set FoundCase to
1331 /// true.
1332 ///
1335  const SwitchCase *Case,
1336  bool &FoundCase,
1337  SmallVectorImpl<const Stmt*> &ResultStmts) {
1338  // If this is a null statement, just succeed.
1339  if (!S)
1340  return Case ? CSFC_Success : CSFC_FallThrough;
1341 
1342  // If this is the switchcase (case 4: or default) that we're looking for, then
1343  // we're in business. Just add the substatement.
1344  if (const SwitchCase *SC = dyn_cast<SwitchCase>(S)) {
1345  if (S == Case) {
1346  FoundCase = true;
1347  return CollectStatementsForCase(SC->getSubStmt(), nullptr, FoundCase,
1348  ResultStmts);
1349  }
1350 
1351  // Otherwise, this is some other case or default statement, just ignore it.
1352  return CollectStatementsForCase(SC->getSubStmt(), Case, FoundCase,
1353  ResultStmts);
1354  }
1355 
1356  // If we are in the live part of the code and we found our break statement,
1357  // return a success!
1358  if (!Case && isa<BreakStmt>(S))
1359  return CSFC_Success;
1360 
1361  // If this is a switch statement, then it might contain the SwitchCase, the
1362  // break, or neither.
1363  if (const CompoundStmt *CS = dyn_cast<CompoundStmt>(S)) {
1364  // Handle this as two cases: we might be looking for the SwitchCase (if so
1365  // the skipped statements must be skippable) or we might already have it.
1366  CompoundStmt::const_body_iterator I = CS->body_begin(), E = CS->body_end();
1367  if (Case) {
1368  // Keep track of whether we see a skipped declaration. The code could be
1369  // using the declaration even if it is skipped, so we can't optimize out
1370  // the decl if the kept statements might refer to it.
1371  bool HadSkippedDecl = false;
1372 
1373  // If we're looking for the case, just see if we can skip each of the
1374  // substatements.
1375  for (; Case && I != E; ++I) {
1376  HadSkippedDecl |= isa<DeclStmt>(*I);
1377 
1378  switch (CollectStatementsForCase(*I, Case, FoundCase, ResultStmts)) {
1379  case CSFC_Failure: return CSFC_Failure;
1380  case CSFC_Success:
1381  // A successful result means that either 1) that the statement doesn't
1382  // have the case and is skippable, or 2) does contain the case value
1383  // and also contains the break to exit the switch. In the later case,
1384  // we just verify the rest of the statements are elidable.
1385  if (FoundCase) {
1386  // If we found the case and skipped declarations, we can't do the
1387  // optimization.
1388  if (HadSkippedDecl)
1389  return CSFC_Failure;
1390 
1391  for (++I; I != E; ++I)
1392  if (CodeGenFunction::ContainsLabel(*I, true))
1393  return CSFC_Failure;
1394  return CSFC_Success;
1395  }
1396  break;
1397  case CSFC_FallThrough:
1398  // If we have a fallthrough condition, then we must have found the
1399  // case started to include statements. Consider the rest of the
1400  // statements in the compound statement as candidates for inclusion.
1401  assert(FoundCase && "Didn't find case but returned fallthrough?");
1402  // We recursively found Case, so we're not looking for it anymore.
1403  Case = nullptr;
1404 
1405  // If we found the case and skipped declarations, we can't do the
1406  // optimization.
1407  if (HadSkippedDecl)
1408  return CSFC_Failure;
1409  break;
1410  }
1411  }
1412  }
1413 
1414  // If we have statements in our range, then we know that the statements are
1415  // live and need to be added to the set of statements we're tracking.
1416  for (; I != E; ++I) {
1417  switch (CollectStatementsForCase(*I, nullptr, FoundCase, ResultStmts)) {
1418  case CSFC_Failure: return CSFC_Failure;
1419  case CSFC_FallThrough:
1420  // A fallthrough result means that the statement was simple and just
1421  // included in ResultStmt, keep adding them afterwards.
1422  break;
1423  case CSFC_Success:
1424  // A successful result means that we found the break statement and
1425  // stopped statement inclusion. We just ensure that any leftover stmts
1426  // are skippable and return success ourselves.
1427  for (++I; I != E; ++I)
1428  if (CodeGenFunction::ContainsLabel(*I, true))
1429  return CSFC_Failure;
1430  return CSFC_Success;
1431  }
1432  }
1433 
1434  return Case ? CSFC_Success : CSFC_FallThrough;
1435  }
1436 
1437  // Okay, this is some other statement that we don't handle explicitly, like a
1438  // for statement or increment etc. If we are skipping over this statement,
1439  // just verify it doesn't have labels, which would make it invalid to elide.
1440  if (Case) {
1441  if (CodeGenFunction::ContainsLabel(S, true))
1442  return CSFC_Failure;
1443  return CSFC_Success;
1444  }
1445 
1446  // Otherwise, we want to include this statement. Everything is cool with that
1447  // so long as it doesn't contain a break out of the switch we're in.
1449 
1450  // Otherwise, everything is great. Include the statement and tell the caller
1451  // that we fall through and include the next statement as well.
1452  ResultStmts.push_back(S);
1453  return CSFC_FallThrough;
1454 }
1455 
1456 /// FindCaseStatementsForValue - Find the case statement being jumped to and
1457 /// then invoke CollectStatementsForCase to find the list of statements to emit
1458 /// for a switch on constant. See the comment above CollectStatementsForCase
1459 /// for more details.
1461  const llvm::APSInt &ConstantCondValue,
1462  SmallVectorImpl<const Stmt*> &ResultStmts,
1463  ASTContext &C,
1464  const SwitchCase *&ResultCase) {
1465  // First step, find the switch case that is being branched to. We can do this
1466  // efficiently by scanning the SwitchCase list.
1467  const SwitchCase *Case = S.getSwitchCaseList();
1468  const DefaultStmt *DefaultCase = nullptr;
1469 
1470  for (; Case; Case = Case->getNextSwitchCase()) {
1471  // It's either a default or case. Just remember the default statement in
1472  // case we're not jumping to any numbered cases.
1473  if (const DefaultStmt *DS = dyn_cast<DefaultStmt>(Case)) {
1474  DefaultCase = DS;
1475  continue;
1476  }
1477 
1478  // Check to see if this case is the one we're looking for.
1479  const CaseStmt *CS = cast<CaseStmt>(Case);
1480  // Don't handle case ranges yet.
1481  if (CS->getRHS()) return false;
1482 
1483  // If we found our case, remember it as 'case'.
1484  if (CS->getLHS()->EvaluateKnownConstInt(C) == ConstantCondValue)
1485  break;
1486  }
1487 
1488  // If we didn't find a matching case, we use a default if it exists, or we
1489  // elide the whole switch body!
1490  if (!Case) {
1491  // It is safe to elide the body of the switch if it doesn't contain labels
1492  // etc. If it is safe, return successfully with an empty ResultStmts list.
1493  if (!DefaultCase)
1494  return !CodeGenFunction::ContainsLabel(&S);
1495  Case = DefaultCase;
1496  }
1497 
1498  // Ok, we know which case is being jumped to, try to collect all the
1499  // statements that follow it. This can fail for a variety of reasons. Also,
1500  // check to see that the recursive walk actually found our case statement.
1501  // Insane cases like this can fail to find it in the recursive walk since we
1502  // don't handle every stmt kind:
1503  // switch (4) {
1504  // while (1) {
1505  // case 4: ...
1506  bool FoundCase = false;
1507  ResultCase = Case;
1508  return CollectStatementsForCase(S.getBody(), Case, FoundCase,
1509  ResultStmts) != CSFC_Failure &&
1510  FoundCase;
1511 }
1512 
1514  // Handle nested switch statements.
1515  llvm::SwitchInst *SavedSwitchInsn = SwitchInsn;
1516  SmallVector<uint64_t, 16> *SavedSwitchWeights = SwitchWeights;
1517  llvm::BasicBlock *SavedCRBlock = CaseRangeBlock;
1518 
1519  // See if we can constant fold the condition of the switch and therefore only
1520  // emit the live case statement (if any) of the switch.
1521  llvm::APSInt ConstantCondValue;
1522  if (ConstantFoldsToSimpleInteger(S.getCond(), ConstantCondValue)) {
1523  SmallVector<const Stmt*, 4> CaseStmts;
1524  const SwitchCase *Case = nullptr;
1525  if (FindCaseStatementsForValue(S, ConstantCondValue, CaseStmts,
1526  getContext(), Case)) {
1527  if (Case)
1529  RunCleanupsScope ExecutedScope(*this);
1530 
1531  // Emit the condition variable if needed inside the entire cleanup scope
1532  // used by this special case for constant folded switches.
1533  if (S.getConditionVariable())
1535 
1536  // At this point, we are no longer "within" a switch instance, so
1537  // we can temporarily enforce this to ensure that any embedded case
1538  // statements are not emitted.
1539  SwitchInsn = nullptr;
1540 
1541  // Okay, we can dead code eliminate everything except this case. Emit the
1542  // specified series of statements and we're good.
1543  for (unsigned i = 0, e = CaseStmts.size(); i != e; ++i)
1544  EmitStmt(CaseStmts[i]);
1546 
1547  // Now we want to restore the saved switch instance so that nested
1548  // switches continue to function properly
1549  SwitchInsn = SavedSwitchInsn;
1550 
1551  return;
1552  }
1553  }
1554 
1555  JumpDest SwitchExit = getJumpDestInCurrentScope("sw.epilog");
1556 
1557  RunCleanupsScope ConditionScope(*this);
1558  if (S.getConditionVariable())
1560  llvm::Value *CondV = EmitScalarExpr(S.getCond());
1561 
1562  // Create basic block to hold stuff that comes after switch
1563  // statement. We also need to create a default block now so that
1564  // explicit case ranges tests can have a place to jump to on
1565  // failure.
1566  llvm::BasicBlock *DefaultBlock = createBasicBlock("sw.default");
1567  SwitchInsn = Builder.CreateSwitch(CondV, DefaultBlock);
1568  if (PGO.haveRegionCounts()) {
1569  // Walk the SwitchCase list to find how many there are.
1570  uint64_t DefaultCount = 0;
1571  unsigned NumCases = 0;
1572  for (const SwitchCase *Case = S.getSwitchCaseList();
1573  Case;
1574  Case = Case->getNextSwitchCase()) {
1575  if (isa<DefaultStmt>(Case))
1576  DefaultCount = getProfileCount(Case);
1577  NumCases += 1;
1578  }
1579  SwitchWeights = new SmallVector<uint64_t, 16>();
1580  SwitchWeights->reserve(NumCases);
1581  // The default needs to be first. We store the edge count, so we already
1582  // know the right weight.
1583  SwitchWeights->push_back(DefaultCount);
1584  }
1585  CaseRangeBlock = DefaultBlock;
1586 
1587  // Clear the insertion point to indicate we are in unreachable code.
1588  Builder.ClearInsertionPoint();
1589 
1590  // All break statements jump to NextBlock. If BreakContinueStack is non-empty
1591  // then reuse last ContinueBlock.
1592  JumpDest OuterContinue;
1593  if (!BreakContinueStack.empty())
1594  OuterContinue = BreakContinueStack.back().ContinueBlock;
1595 
1596  BreakContinueStack.push_back(BreakContinue(SwitchExit, OuterContinue));
1597 
1598  // Emit switch body.
1599  EmitStmt(S.getBody());
1600 
1601  BreakContinueStack.pop_back();
1602 
1603  // Update the default block in case explicit case range tests have
1604  // been chained on top.
1605  SwitchInsn->setDefaultDest(CaseRangeBlock);
1606 
1607  // If a default was never emitted:
1608  if (!DefaultBlock->getParent()) {
1609  // If we have cleanups, emit the default block so that there's a
1610  // place to jump through the cleanups from.
1611  if (ConditionScope.requiresCleanups()) {
1612  EmitBlock(DefaultBlock);
1613 
1614  // Otherwise, just forward the default block to the switch end.
1615  } else {
1616  DefaultBlock->replaceAllUsesWith(SwitchExit.getBlock());
1617  delete DefaultBlock;
1618  }
1619  }
1620 
1621  ConditionScope.ForceCleanup();
1622 
1623  // Emit continuation.
1624  EmitBlock(SwitchExit.getBlock(), true);
1626 
1627  if (SwitchWeights) {
1628  assert(SwitchWeights->size() == 1 + SwitchInsn->getNumCases() &&
1629  "switch weights do not match switch cases");
1630  // If there's only one jump destination there's no sense weighting it.
1631  if (SwitchWeights->size() > 1)
1632  SwitchInsn->setMetadata(llvm::LLVMContext::MD_prof,
1633  createProfileWeights(*SwitchWeights));
1634  delete SwitchWeights;
1635  }
1636  SwitchInsn = SavedSwitchInsn;
1637  SwitchWeights = SavedSwitchWeights;
1638  CaseRangeBlock = SavedCRBlock;
1639 }
1640 
1641 static std::string
1642 SimplifyConstraint(const char *Constraint, const TargetInfo &Target,
1644  std::string Result;
1645 
1646  while (*Constraint) {
1647  switch (*Constraint) {
1648  default:
1649  Result += Target.convertConstraint(Constraint);
1650  break;
1651  // Ignore these
1652  case '*':
1653  case '?':
1654  case '!':
1655  case '=': // Will see this and the following in mult-alt constraints.
1656  case '+':
1657  break;
1658  case '#': // Ignore the rest of the constraint alternative.
1659  while (Constraint[1] && Constraint[1] != ',')
1660  Constraint++;
1661  break;
1662  case '&':
1663  case '%':
1664  Result += *Constraint;
1665  while (Constraint[1] && Constraint[1] == *Constraint)
1666  Constraint++;
1667  break;
1668  case ',':
1669  Result += "|";
1670  break;
1671  case 'g':
1672  Result += "imr";
1673  break;
1674  case '[': {
1675  assert(OutCons &&
1676  "Must pass output names to constraints with a symbolic name");
1677  unsigned Index;
1678  bool result = Target.resolveSymbolicName(Constraint,
1679  &(*OutCons)[0],
1680  OutCons->size(), Index);
1681  assert(result && "Could not resolve symbolic name"); (void)result;
1682  Result += llvm::utostr(Index);
1683  break;
1684  }
1685  }
1686 
1687  Constraint++;
1688  }
1689 
1690  return Result;
1691 }
1692 
1693 /// AddVariableConstraints - Look at AsmExpr and if it is a variable declared
1694 /// as using a particular register add that as a constraint that will be used
1695 /// in this asm stmt.
1696 static std::string
1697 AddVariableConstraints(const std::string &Constraint, const Expr &AsmExpr,
1699  const AsmStmt &Stmt, const bool EarlyClobber) {
1700  const DeclRefExpr *AsmDeclRef = dyn_cast<DeclRefExpr>(&AsmExpr);
1701  if (!AsmDeclRef)
1702  return Constraint;
1703  const ValueDecl &Value = *AsmDeclRef->getDecl();
1704  const VarDecl *Variable = dyn_cast<VarDecl>(&Value);
1705  if (!Variable)
1706  return Constraint;
1707  if (Variable->getStorageClass() != SC_Register)
1708  return Constraint;
1709  AsmLabelAttr *Attr = Variable->getAttr<AsmLabelAttr>();
1710  if (!Attr)
1711  return Constraint;
1712  StringRef Register = Attr->getLabel();
1713  assert(Target.isValidGCCRegisterName(Register));
1714  // We're using validateOutputConstraint here because we only care if
1715  // this is a register constraint.
1716  TargetInfo::ConstraintInfo Info(Constraint, "");
1717  if (Target.validateOutputConstraint(Info) &&
1718  !Info.allowsRegister()) {
1719  CGM.ErrorUnsupported(&Stmt, "__asm__");
1720  return Constraint;
1721  }
1722  // Canonicalize the register here before returning it.
1723  Register = Target.getNormalizedGCCRegisterName(Register);
1724  return (EarlyClobber ? "&{" : "{") + Register.str() + "}";
1725 }
1726 
1727 llvm::Value*
1728 CodeGenFunction::EmitAsmInputLValue(const TargetInfo::ConstraintInfo &Info,
1729  LValue InputValue, QualType InputType,
1730  std::string &ConstraintStr,
1731  SourceLocation Loc) {
1732  llvm::Value *Arg;
1733  if (Info.allowsRegister() || !Info.allowsMemory()) {
1735  Arg = EmitLoadOfLValue(InputValue, Loc).getScalarVal();
1736  } else {
1737  llvm::Type *Ty = ConvertType(InputType);
1738  uint64_t Size = CGM.getDataLayout().getTypeSizeInBits(Ty);
1739  if (Size <= 64 && llvm::isPowerOf2_64(Size)) {
1740  Ty = llvm::IntegerType::get(getLLVMContext(), Size);
1741  Ty = llvm::PointerType::getUnqual(Ty);
1742 
1743  Arg = Builder.CreateLoad(Builder.CreateBitCast(InputValue.getAddress(),
1744  Ty));
1745  } else {
1746  Arg = InputValue.getAddress();
1747  ConstraintStr += '*';
1748  }
1749  }
1750  } else {
1751  Arg = InputValue.getAddress();
1752  ConstraintStr += '*';
1753  }
1754 
1755  return Arg;
1756 }
1757 
1758 llvm::Value* CodeGenFunction::EmitAsmInput(
1759  const TargetInfo::ConstraintInfo &Info,
1760  const Expr *InputExpr,
1761  std::string &ConstraintStr) {
1762  // If this can't be a register or memory, i.e., has to be a constant
1763  // (immediate or symbolic), try to emit it as such.
1764  if (!Info.allowsRegister() && !Info.allowsMemory()) {
1765  llvm::APSInt Result;
1766  if (InputExpr->EvaluateAsInt(Result, getContext()))
1767  return llvm::ConstantInt::get(getLLVMContext(), Result);
1768  assert(!Info.requiresImmediateConstant() &&
1769  "Required-immediate inlineasm arg isn't constant?");
1770  }
1771 
1772  if (Info.allowsRegister() || !Info.allowsMemory())
1774  return EmitScalarExpr(InputExpr);
1775 
1776  InputExpr = InputExpr->IgnoreParenNoopCasts(getContext());
1777  LValue Dest = EmitLValue(InputExpr);
1778  return EmitAsmInputLValue(Info, Dest, InputExpr->getType(), ConstraintStr,
1779  InputExpr->getExprLoc());
1780 }
1781 
1782 /// getAsmSrcLocInfo - Return the !srcloc metadata node to attach to an inline
1783 /// asm call instruction. The !srcloc MDNode contains a list of constant
1784 /// integers which are the source locations of the start of each line in the
1785 /// asm.
1786 static llvm::MDNode *getAsmSrcLocInfo(const StringLiteral *Str,
1787  CodeGenFunction &CGF) {
1789  // Add the location of the first line to the MDNode.
1790  Locs.push_back(llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(
1791  CGF.Int32Ty, Str->getLocStart().getRawEncoding())));
1792  StringRef StrVal = Str->getString();
1793  if (!StrVal.empty()) {
1794  const SourceManager &SM = CGF.CGM.getContext().getSourceManager();
1795  const LangOptions &LangOpts = CGF.CGM.getLangOpts();
1796 
1797  // Add the location of the start of each subsequent line of the asm to the
1798  // MDNode.
1799  for (unsigned i = 0, e = StrVal.size()-1; i != e; ++i) {
1800  if (StrVal[i] != '\n') continue;
1801  SourceLocation LineLoc = Str->getLocationOfByte(i+1, SM, LangOpts,
1802  CGF.getTarget());
1803  Locs.push_back(llvm::ConstantAsMetadata::get(
1804  llvm::ConstantInt::get(CGF.Int32Ty, LineLoc.getRawEncoding())));
1805  }
1806  }
1807 
1808  return llvm::MDNode::get(CGF.getLLVMContext(), Locs);
1809 }
1810 
1812  // Assemble the final asm string.
1813  std::string AsmString = S.generateAsmString(getContext());
1814 
1815  // Get all the output and input constraints together.
1816  SmallVector<TargetInfo::ConstraintInfo, 4> OutputConstraintInfos;
1817  SmallVector<TargetInfo::ConstraintInfo, 4> InputConstraintInfos;
1818 
1819  for (unsigned i = 0, e = S.getNumOutputs(); i != e; i++) {
1820  StringRef Name;
1821  if (const GCCAsmStmt *GAS = dyn_cast<GCCAsmStmt>(&S))
1822  Name = GAS->getOutputName(i);
1824  bool IsValid = getTarget().validateOutputConstraint(Info); (void)IsValid;
1825  assert(IsValid && "Failed to parse output constraint");
1826  OutputConstraintInfos.push_back(Info);
1827  }
1828 
1829  for (unsigned i = 0, e = S.getNumInputs(); i != e; i++) {
1830  StringRef Name;
1831  if (const GCCAsmStmt *GAS = dyn_cast<GCCAsmStmt>(&S))
1832  Name = GAS->getInputName(i);
1834  bool IsValid =
1835  getTarget().validateInputConstraint(OutputConstraintInfos.data(),
1836  S.getNumOutputs(), Info);
1837  assert(IsValid && "Failed to parse input constraint"); (void)IsValid;
1838  InputConstraintInfos.push_back(Info);
1839  }
1840 
1841  std::string Constraints;
1842 
1843  std::vector<LValue> ResultRegDests;
1844  std::vector<QualType> ResultRegQualTys;
1845  std::vector<llvm::Type *> ResultRegTypes;
1846  std::vector<llvm::Type *> ResultTruncRegTypes;
1847  std::vector<llvm::Type *> ArgTypes;
1848  std::vector<llvm::Value*> Args;
1849 
1850  // Keep track of inout constraints.
1851  std::string InOutConstraints;
1852  std::vector<llvm::Value*> InOutArgs;
1853  std::vector<llvm::Type*> InOutArgTypes;
1854 
1855  // An inline asm can be marked readonly if it meets the following conditions:
1856  // - it doesn't have any sideeffects
1857  // - it doesn't clobber memory
1858  // - it doesn't return a value by-reference
1859  // It can be marked readnone if it doesn't have any input memory constraints
1860  // in addition to meeting the conditions listed above.
1861  bool ReadOnly = true, ReadNone = true;
1862 
1863  for (unsigned i = 0, e = S.getNumOutputs(); i != e; i++) {
1864  TargetInfo::ConstraintInfo &Info = OutputConstraintInfos[i];
1865 
1866  // Simplify the output constraint.
1867  std::string OutputConstraint(S.getOutputConstraint(i));
1868  OutputConstraint = SimplifyConstraint(OutputConstraint.c_str() + 1,
1869  getTarget());
1870 
1871  const Expr *OutExpr = S.getOutputExpr(i);
1872  OutExpr = OutExpr->IgnoreParenNoopCasts(getContext());
1873 
1874  OutputConstraint = AddVariableConstraints(OutputConstraint, *OutExpr,
1875  getTarget(), CGM, S,
1876  Info.earlyClobber());
1877 
1878  LValue Dest = EmitLValue(OutExpr);
1879  if (!Constraints.empty())
1880  Constraints += ',';
1881 
1882  // If this is a register output, then make the inline asm return it
1883  // by-value. If this is a memory result, return the value by-reference.
1884  if (!Info.allowsMemory() && hasScalarEvaluationKind(OutExpr->getType())) {
1885  Constraints += "=" + OutputConstraint;
1886  ResultRegQualTys.push_back(OutExpr->getType());
1887  ResultRegDests.push_back(Dest);
1888  ResultRegTypes.push_back(ConvertTypeForMem(OutExpr->getType()));
1889  ResultTruncRegTypes.push_back(ResultRegTypes.back());
1890 
1891  // If this output is tied to an input, and if the input is larger, then
1892  // we need to set the actual result type of the inline asm node to be the
1893  // same as the input type.
1894  if (Info.hasMatchingInput()) {
1895  unsigned InputNo;
1896  for (InputNo = 0; InputNo != S.getNumInputs(); ++InputNo) {
1897  TargetInfo::ConstraintInfo &Input = InputConstraintInfos[InputNo];
1898  if (Input.hasTiedOperand() && Input.getTiedOperand() == i)
1899  break;
1900  }
1901  assert(InputNo != S.getNumInputs() && "Didn't find matching input!");
1902 
1903  QualType InputTy = S.getInputExpr(InputNo)->getType();
1904  QualType OutputType = OutExpr->getType();
1905 
1906  uint64_t InputSize = getContext().getTypeSize(InputTy);
1907  if (getContext().getTypeSize(OutputType) < InputSize) {
1908  // Form the asm to return the value as a larger integer or fp type.
1909  ResultRegTypes.back() = ConvertType(InputTy);
1910  }
1911  }
1912  if (llvm::Type* AdjTy =
1913  getTargetHooks().adjustInlineAsmType(*this, OutputConstraint,
1914  ResultRegTypes.back()))
1915  ResultRegTypes.back() = AdjTy;
1916  else {
1917  CGM.getDiags().Report(S.getAsmLoc(),
1918  diag::err_asm_invalid_type_in_input)
1919  << OutExpr->getType() << OutputConstraint;
1920  }
1921  } else {
1922  ArgTypes.push_back(Dest.getAddress()->getType());
1923  Args.push_back(Dest.getAddress());
1924  Constraints += "=*";
1925  Constraints += OutputConstraint;
1926  ReadOnly = ReadNone = false;
1927  }
1928 
1929  if (Info.isReadWrite()) {
1930  InOutConstraints += ',';
1931 
1932  const Expr *InputExpr = S.getOutputExpr(i);
1933  llvm::Value *Arg = EmitAsmInputLValue(Info, Dest, InputExpr->getType(),
1934  InOutConstraints,
1935  InputExpr->getExprLoc());
1936 
1937  if (llvm::Type* AdjTy =
1938  getTargetHooks().adjustInlineAsmType(*this, OutputConstraint,
1939  Arg->getType()))
1940  Arg = Builder.CreateBitCast(Arg, AdjTy);
1941 
1942  if (Info.allowsRegister())
1943  InOutConstraints += llvm::utostr(i);
1944  else
1945  InOutConstraints += OutputConstraint;
1946 
1947  InOutArgTypes.push_back(Arg->getType());
1948  InOutArgs.push_back(Arg);
1949  }
1950  }
1951 
1952  // If this is a Microsoft-style asm blob, store the return registers (EAX:EDX)
1953  // to the return value slot. Only do this when returning in registers.
1954  if (isa<MSAsmStmt>(&S)) {
1955  const ABIArgInfo &RetAI = CurFnInfo->getReturnInfo();
1956  if (RetAI.isDirect() || RetAI.isExtend()) {
1957  // Make a fake lvalue for the return value slot.
1958  LValue ReturnSlot = MakeAddrLValue(ReturnValue, FnRetTy);
1960  *this, ReturnSlot, Constraints, ResultRegTypes, ResultTruncRegTypes,
1961  ResultRegDests, AsmString, S.getNumOutputs());
1962  SawAsmBlock = true;
1963  }
1964  }
1965 
1966  for (unsigned i = 0, e = S.getNumInputs(); i != e; i++) {
1967  const Expr *InputExpr = S.getInputExpr(i);
1968 
1969  TargetInfo::ConstraintInfo &Info = InputConstraintInfos[i];
1970 
1971  if (Info.allowsMemory())
1972  ReadNone = false;
1973 
1974  if (!Constraints.empty())
1975  Constraints += ',';
1976 
1977  // Simplify the input constraint.
1978  std::string InputConstraint(S.getInputConstraint(i));
1979  InputConstraint = SimplifyConstraint(InputConstraint.c_str(), getTarget(),
1980  &OutputConstraintInfos);
1981 
1982  InputConstraint = AddVariableConstraints(
1983  InputConstraint, *InputExpr->IgnoreParenNoopCasts(getContext()),
1984  getTarget(), CGM, S, false /* No EarlyClobber */);
1985 
1986  llvm::Value *Arg = EmitAsmInput(Info, InputExpr, Constraints);
1987 
1988  // If this input argument is tied to a larger output result, extend the
1989  // input to be the same size as the output. The LLVM backend wants to see
1990  // the input and output of a matching constraint be the same size. Note
1991  // that GCC does not define what the top bits are here. We use zext because
1992  // that is usually cheaper, but LLVM IR should really get an anyext someday.
1993  if (Info.hasTiedOperand()) {
1994  unsigned Output = Info.getTiedOperand();
1995  QualType OutputType = S.getOutputExpr(Output)->getType();
1996  QualType InputTy = InputExpr->getType();
1997 
1998  if (getContext().getTypeSize(OutputType) >
1999  getContext().getTypeSize(InputTy)) {
2000  // Use ptrtoint as appropriate so that we can do our extension.
2001  if (isa<llvm::PointerType>(Arg->getType()))
2002  Arg = Builder.CreatePtrToInt(Arg, IntPtrTy);
2003  llvm::Type *OutputTy = ConvertType(OutputType);
2004  if (isa<llvm::IntegerType>(OutputTy))
2005  Arg = Builder.CreateZExt(Arg, OutputTy);
2006  else if (isa<llvm::PointerType>(OutputTy))
2007  Arg = Builder.CreateZExt(Arg, IntPtrTy);
2008  else {
2009  assert(OutputTy->isFloatingPointTy() && "Unexpected output type");
2010  Arg = Builder.CreateFPExt(Arg, OutputTy);
2011  }
2012  }
2013  }
2014  if (llvm::Type* AdjTy =
2015  getTargetHooks().adjustInlineAsmType(*this, InputConstraint,
2016  Arg->getType()))
2017  Arg = Builder.CreateBitCast(Arg, AdjTy);
2018  else
2019  CGM.getDiags().Report(S.getAsmLoc(), diag::err_asm_invalid_type_in_input)
2020  << InputExpr->getType() << InputConstraint;
2021 
2022  ArgTypes.push_back(Arg->getType());
2023  Args.push_back(Arg);
2024  Constraints += InputConstraint;
2025  }
2026 
2027  // Append the "input" part of inout constraints last.
2028  for (unsigned i = 0, e = InOutArgs.size(); i != e; i++) {
2029  ArgTypes.push_back(InOutArgTypes[i]);
2030  Args.push_back(InOutArgs[i]);
2031  }
2032  Constraints += InOutConstraints;
2033 
2034  // Clobbers
2035  for (unsigned i = 0, e = S.getNumClobbers(); i != e; i++) {
2036  StringRef Clobber = S.getClobber(i);
2037 
2038  if (Clobber == "memory")
2039  ReadOnly = ReadNone = false;
2040  else if (Clobber != "cc")
2041  Clobber = getTarget().getNormalizedGCCRegisterName(Clobber);
2042 
2043  if (!Constraints.empty())
2044  Constraints += ',';
2045 
2046  Constraints += "~{";
2047  Constraints += Clobber;
2048  Constraints += '}';
2049  }
2050 
2051  // Add machine specific clobbers
2052  std::string MachineClobbers = getTarget().getClobbers();
2053  if (!MachineClobbers.empty()) {
2054  if (!Constraints.empty())
2055  Constraints += ',';
2056  Constraints += MachineClobbers;
2057  }
2058 
2059  llvm::Type *ResultType;
2060  if (ResultRegTypes.empty())
2061  ResultType = VoidTy;
2062  else if (ResultRegTypes.size() == 1)
2063  ResultType = ResultRegTypes[0];
2064  else
2065  ResultType = llvm::StructType::get(getLLVMContext(), ResultRegTypes);
2066 
2067  llvm::FunctionType *FTy =
2068  llvm::FunctionType::get(ResultType, ArgTypes, false);
2069 
2070  bool HasSideEffect = S.isVolatile() || S.getNumOutputs() == 0;
2071  llvm::InlineAsm::AsmDialect AsmDialect = isa<MSAsmStmt>(&S) ?
2072  llvm::InlineAsm::AD_Intel : llvm::InlineAsm::AD_ATT;
2073  llvm::InlineAsm *IA =
2074  llvm::InlineAsm::get(FTy, AsmString, Constraints, HasSideEffect,
2075  /* IsAlignStack */ false, AsmDialect);
2076  llvm::CallInst *Result = Builder.CreateCall(IA, Args);
2077  Result->addAttribute(llvm::AttributeSet::FunctionIndex,
2078  llvm::Attribute::NoUnwind);
2079 
2080  // Attach readnone and readonly attributes.
2081  if (!HasSideEffect) {
2082  if (ReadNone)
2083  Result->addAttribute(llvm::AttributeSet::FunctionIndex,
2084  llvm::Attribute::ReadNone);
2085  else if (ReadOnly)
2086  Result->addAttribute(llvm::AttributeSet::FunctionIndex,
2087  llvm::Attribute::ReadOnly);
2088  }
2089 
2090  // Slap the source location of the inline asm into a !srcloc metadata on the
2091  // call.
2092  if (const GCCAsmStmt *gccAsmStmt = dyn_cast<GCCAsmStmt>(&S)) {
2093  Result->setMetadata("srcloc", getAsmSrcLocInfo(gccAsmStmt->getAsmString(),
2094  *this));
2095  } else {
2096  // At least put the line number on MS inline asm blobs.
2097  auto Loc = llvm::ConstantInt::get(Int32Ty, S.getAsmLoc().getRawEncoding());
2098  Result->setMetadata("srcloc",
2099  llvm::MDNode::get(getLLVMContext(),
2100  llvm::ConstantAsMetadata::get(Loc)));
2101  }
2102 
2103  // Extract all of the register value results from the asm.
2104  std::vector<llvm::Value*> RegResults;
2105  if (ResultRegTypes.size() == 1) {
2106  RegResults.push_back(Result);
2107  } else {
2108  for (unsigned i = 0, e = ResultRegTypes.size(); i != e; ++i) {
2109  llvm::Value *Tmp = Builder.CreateExtractValue(Result, i, "asmresult");
2110  RegResults.push_back(Tmp);
2111  }
2112  }
2113 
2114  assert(RegResults.size() == ResultRegTypes.size());
2115  assert(RegResults.size() == ResultTruncRegTypes.size());
2116  assert(RegResults.size() == ResultRegDests.size());
2117  for (unsigned i = 0, e = RegResults.size(); i != e; ++i) {
2118  llvm::Value *Tmp = RegResults[i];
2119 
2120  // If the result type of the LLVM IR asm doesn't match the result type of
2121  // the expression, do the conversion.
2122  if (ResultRegTypes[i] != ResultTruncRegTypes[i]) {
2123  llvm::Type *TruncTy = ResultTruncRegTypes[i];
2124 
2125  // Truncate the integer result to the right size, note that TruncTy can be
2126  // a pointer.
2127  if (TruncTy->isFloatingPointTy())
2128  Tmp = Builder.CreateFPTrunc(Tmp, TruncTy);
2129  else if (TruncTy->isPointerTy() && Tmp->getType()->isIntegerTy()) {
2130  uint64_t ResSize = CGM.getDataLayout().getTypeSizeInBits(TruncTy);
2131  Tmp = Builder.CreateTrunc(Tmp,
2132  llvm::IntegerType::get(getLLVMContext(), (unsigned)ResSize));
2133  Tmp = Builder.CreateIntToPtr(Tmp, TruncTy);
2134  } else if (Tmp->getType()->isPointerTy() && TruncTy->isIntegerTy()) {
2135  uint64_t TmpSize =CGM.getDataLayout().getTypeSizeInBits(Tmp->getType());
2136  Tmp = Builder.CreatePtrToInt(Tmp,
2137  llvm::IntegerType::get(getLLVMContext(), (unsigned)TmpSize));
2138  Tmp = Builder.CreateTrunc(Tmp, TruncTy);
2139  } else if (TruncTy->isIntegerTy()) {
2140  Tmp = Builder.CreateTrunc(Tmp, TruncTy);
2141  } else if (TruncTy->isVectorTy()) {
2142  Tmp = Builder.CreateBitCast(Tmp, TruncTy);
2143  }
2144  }
2145 
2146  EmitStoreThroughLValue(RValue::get(Tmp), ResultRegDests[i]);
2147  }
2148 }
2149 
2151  const RecordDecl *RD = S.getCapturedRecordDecl();
2152  QualType RecordTy = getContext().getRecordType(RD);
2153 
2154  // Initialize the captured struct.
2156  CreateMemTemp(RecordTy, "agg.captured"), RecordTy);
2157 
2158  RecordDecl::field_iterator CurField = RD->field_begin();
2160  E = S.capture_init_end();
2161  I != E; ++I, ++CurField) {
2162  LValue LV = EmitLValueForFieldInitialization(SlotLV, *CurField);
2163  if (CurField->hasCapturedVLAType()) {
2164  auto VAT = CurField->getCapturedVLAType();
2165  EmitStoreThroughLValue(RValue::get(VLASizeMap[VAT->getSizeExpr()]), LV);
2166  } else {
2167  EmitInitializerForField(*CurField, LV, *I, None);
2168  }
2169  }
2170 
2171  return SlotLV;
2172 }
2173 
2174 /// Generate an outlined function for the body of a CapturedStmt, store any
2175 /// captured variables into the captured struct, and call the outlined function.
2176 llvm::Function *
2178  LValue CapStruct = InitCapturedStruct(S);
2179 
2180  // Emit the CapturedDecl
2181  CodeGenFunction CGF(CGM, true);
2182  CGCapturedStmtRAII CapInfoRAII(CGF, new CGCapturedStmtInfo(S, K));
2183  llvm::Function *F = CGF.GenerateCapturedStmtFunction(S);
2184  delete CGF.CapturedStmtInfo;
2185 
2186  // Emit call to the helper function.
2187  EmitCallOrInvoke(F, CapStruct.getAddress());
2188 
2189  return F;
2190 }
2191 
2192 llvm::Value *
2194  LValue CapStruct = InitCapturedStruct(S);
2195  return CapStruct.getAddress();
2196 }
2197 
2198 /// Creates the outlined function for a CapturedStmt.
2199 llvm::Function *
2201  assert(CapturedStmtInfo &&
2202  "CapturedStmtInfo should be set when generating the captured function");
2203  const CapturedDecl *CD = S.getCapturedDecl();
2204  const RecordDecl *RD = S.getCapturedRecordDecl();
2205  SourceLocation Loc = S.getLocStart();
2206  assert(CD->hasBody() && "missing CapturedDecl body");
2207 
2208  // Build the argument list.
2209  ASTContext &Ctx = CGM.getContext();
2210  FunctionArgList Args;
2211  Args.append(CD->param_begin(), CD->param_end());
2212 
2213  // Create the function declaration.
2214  FunctionType::ExtInfo ExtInfo;
2215  const CGFunctionInfo &FuncInfo =
2216  CGM.getTypes().arrangeFreeFunctionDeclaration(Ctx.VoidTy, Args, ExtInfo,
2217  /*IsVariadic=*/false);
2218  llvm::FunctionType *FuncLLVMTy = CGM.getTypes().GetFunctionType(FuncInfo);
2219 
2220  llvm::Function *F =
2223  CGM.SetInternalFunctionAttributes(CD, F, FuncInfo);
2224  if (CD->isNothrow())
2225  F->addFnAttr(llvm::Attribute::NoUnwind);
2226 
2227  // Generate the function.
2228  StartFunction(CD, Ctx.VoidTy, F, FuncInfo, Args,
2229  CD->getLocation(),
2230  CD->getBody()->getLocStart());
2231  // Set the context parameter in CapturedStmtInfo.
2232  llvm::Value *DeclPtr = LocalDeclMap[CD->getContextParam()];
2233  assert(DeclPtr && "missing context parameter for CapturedStmt");
2234  CapturedStmtInfo->setContextValue(Builder.CreateLoad(DeclPtr));
2235 
2236  // Initialize variable-length arrays.
2238  Ctx.getTagDeclType(RD));
2239  for (auto *FD : RD->fields()) {
2240  if (FD->hasCapturedVLAType()) {
2241  auto *ExprArg = EmitLoadOfLValue(EmitLValueForField(Base, FD),
2242  S.getLocStart()).getScalarVal();
2243  auto VAT = FD->getCapturedVLAType();
2244  VLASizeMap[VAT->getSizeExpr()] = ExprArg;
2245  }
2246  }
2247 
2248  // If 'this' is captured, load it into CXXThisValue.
2251  LValue ThisLValue = EmitLValueForField(Base, FD);
2252  CXXThisValue = EmitLoadOfLValue(ThisLValue, Loc).getScalarVal();
2253  }
2254 
2255  PGO.assignRegionCounters(CD, F);
2256  CapturedStmtInfo->EmitBody(*this, CD->getBody());
2258 
2259  return F;
2260 }
Expr * getInc()
Definition: Stmt.h:1178
void EmitInitializerForField(FieldDecl *Field, LValue LHS, Expr *Init, ArrayRef< VarDecl * > ArrayIndexes)
Definition: CGClass.cpp:629
void EmitIndirectGotoStmt(const IndirectGotoStmt &S)
Definition: CGStmt.cpp:499
const SwitchCase * getNextSwitchCase() const
Definition: Stmt.h:667
virtual void EmitBody(CodeGenFunction &CGF, const Stmt *S)
Emit the captured statement body.
Stmt * body_back()
Definition: Stmt.h:589
CapturedDecl * getCapturedDecl()
Retrieve the outlined function declaration.
Definition: Stmt.h:2104
unsigned getNumOutputs() const
Definition: Stmt.h:1447
body_iterator body_end()
Definition: Stmt.h:587
void EmitOMPTaskwaitDirective(const OMPTaskwaitDirective &S)
StringRef getName() const
Definition: Decl.h:168
void EmitSEHLeaveStmt(const SEHLeaveStmt &S)
bool isEvaluatable(const ASTContext &Ctx) const
llvm::Type * ConvertTypeForMem(QualType T)
void EmitBranchOnBoolExpr(const Expr *Cond, llvm::BasicBlock *TrueBlock, llvm::BasicBlock *FalseBlock, uint64_t TrueCount)
void EmitGotoStmt(const GotoStmt &S)
Definition: CGStmt.cpp:488
bool resolveSymbolicName(const char *&Name, ConstraintInfo *OutputConstraints, unsigned NumOutputs, unsigned &Index) const
void EmitAttributedStmt(const AttributedStmt &S)
Definition: CGStmt.cpp:468
bool hasMatchingInput() const
Return true if this output operand has a matching (tied) input operand.
Expr * getCond()
Definition: Stmt.h:1066
llvm::Module & getModule() const
void EmitCXXTryStmt(const CXXTryStmt &S)
const TargetInfo & getTarget() const
std::pair< llvm::Value *, llvm::Value * > getComplexVal() const
Definition: CGValue.h:61
static stable_iterator stable_end()
Create a stable reference to the bottom of the EH stack.
Definition: EHScopeStack.h:369
const Expr * getOutputExpr(unsigned i) const
Definition: Stmt.cpp:344
Defines the PrettyStackTraceEntry class, which is used to make crashes give more contextual informati...
Represents an attribute applied to a statement.
Definition: Stmt.h:833
llvm::Value * EmitCompoundStmt(const CompoundStmt &S, bool GetLast=false, AggValueSlot AVS=AggValueSlot::ignored())
Definition: CGStmt.cpp:275
void EmitAutoVarDecl(const VarDecl &D)
Definition: CGDecl.cpp:847
const llvm::DataLayout & getDataLayout() const
void EmitOMPOrderedDirective(const OMPOrderedDirective &S)
bool validateOutputConstraint(ConstraintInfo &Info) const
void EmitStoreThroughLValue(RValue Src, LValue Dst, bool isInit=false)
Definition: CGExpr.cpp:1469
void EmitComplexExprIntoLValue(const Expr *E, LValue dest, bool isInit)
QualType getRecordType(const RecordDecl *Decl) const
DiagnosticBuilder Report(SourceLocation Loc, unsigned DiagID)
Issue the message to the client.
Definition: Diagnostic.h:1118
const Stmt * getElse() const
Definition: Stmt.h:918
SourceLocation getLocStart() const LLVM_READONLY
Definition: Expr.h:1607
const LangOptions & getLangOpts() const
LValue EmitLValueForFieldInitialization(LValue Base, const FieldDecl *Field)
Definition: CGExpr.cpp:2794
unsigned getRawEncoding() const
When a SourceLocation itself cannot be used, this returns an (opaque) 32-bit integer encoding for it...
VarDecl * getConditionVariable() const
Retrieve the variable declared in this "for" statement, if any.
Definition: Stmt.cpp:925
const CGFunctionInfo & arrangeFreeFunctionDeclaration(QualType ResTy, const FunctionArgList &Args, const FunctionType::ExtInfo &Info, bool isVariadic)
Definition: CGCall.cpp:460
llvm::Value * getAddress() const
Definition: CGValue.h:265
void EmitOMPParallelForSimdDirective(const OMPParallelForSimdDirective &S)
Stmt * getSubStmt()
Definition: Stmt.h:763
void EmitOMPCriticalDirective(const OMPCriticalDirective &S)
uint64_t getProfileCount(const Stmt *S)
Get the profiler's count for the given statement.
field_iterator field_begin() const
Definition: Decl.cpp:3629
uint64_t getTypeSize(QualType T) const
Return the size of the specified (complete) type T, in bits.
Definition: ASTContext.h:1701
void EmitLabel(const LabelDecl *D)
Definition: CGStmt.cpp:413
void SimplifyForwardingBlocks(llvm::BasicBlock *BB)
Definition: CGStmt.cpp:326
bool isVoidType() const
Definition: Type.h:5426
JumpDest getJumpDestForLabel(const LabelDecl *S)
Definition: CGStmt.cpp:402
void EmitCXXForRangeStmt(const CXXForRangeStmt &S, ArrayRef< const Attr * > Attrs=None)
Definition: CGStmt.cpp:936
void EmitOMPSimdDirective(const OMPSimdDirective &S)
Stmt * getBody()
Definition: Stmt.h:1114
void setScopeDepth(EHScopeStack::stable_iterator depth)
unsigned getNumInputs() const
Definition: Stmt.h:1469
Holds long-lived AST nodes (such as types and decls) that can be referred to throughout the semantic ...
Definition: ASTContext.h:89
LineState State
RValue EmitReferenceBindingToExpr(const Expr *E)
Emits a reference binding to the passed in expression.
Definition: CGExpr.cpp:442
bool isReferenceType() const
Definition: Type.h:5241
llvm::CallSite EmitCallOrInvoke(llvm::Value *Callee, ArrayRef< llvm::Value * > Args, const Twine &Name="")
Definition: CGCall.cpp:3069
SourceLocation getLBracLoc() const
Definition: Stmt.h:633
static bool FindCaseStatementsForValue(const SwitchStmt &S, const llvm::APSInt &ConstantCondValue, SmallVectorImpl< const Stmt * > &ResultStmts, ASTContext &C, const SwitchCase *&ResultCase)
Definition: CGStmt.cpp:1460
Keeps track of the various options that can be enabled, which controls the dialect of C or C++ that i...
Definition: LangOptions.h:48
StorageClass getStorageClass() const
Returns the storage class as written in the source. For the computed linkage of symbol, see getLinkage.
Definition: Decl.h:871
const VarDecl * getNRVOCandidate() const
Retrieve the variable that might be used for the named return value optimization. ...
Definition: Stmt.h:1378
RValue EmitAnyExpr(const Expr *E, AggValueSlot aggSlot=AggValueSlot::ignored(), bool ignoreResult=false)
Definition: CGExpr.cpp:119
T * getAttr() const
Definition: DeclBase.h:484
LValue MakeAddrLValue(llvm::Value *V, QualType T, CharUnits Alignment=CharUnits())
static bool hasScalarEvaluationKind(QualType T)
StringRef getOutputConstraint(unsigned i) const
Definition: Stmt.cpp:336
void EmitDoStmt(const DoStmt &S, ArrayRef< const Attr * > Attrs=None)
Definition: CGStmt.cpp:775
void pop()
End the current loop.
Definition: CGLoopInfo.cpp:114
bool isValidGCCRegisterName(StringRef Name) const
Returns whether the passed in string is a valid register name according to GCC.
void EmitOMPCancellationPointDirective(const OMPCancellationPointDirective &S)
RAII for correct setting/restoring of CapturedStmtInfo.
field_range fields() const
Definition: Decl.h:3349
Stmt * getBody()
Definition: Stmt.h:1179
void EmitContinueStmt(const ContinueStmt &S)
Definition: CGStmt.cpp:1124
void EmitOMPTargetDirective(const OMPTargetDirective &S)
Stmt * getInit()
Definition: Stmt.h:1158
llvm::Value * getAggregateAddr() const
getAggregateAddr() - Return the Value* of the address of the aggregate.
Definition: CGValue.h:66
static OMPLinearClause * Create(const ASTContext &C, SourceLocation StartLoc, SourceLocation LParenLoc, SourceLocation ColonLoc, SourceLocation EndLoc, ArrayRef< Expr * > VL, ArrayRef< Expr * > IL, Expr *Step, Expr *CalcStep)
Creates clause with a list of variables VL and a linear step Step.
void EmitSwitchStmt(const SwitchStmt &S)
Definition: CGStmt.cpp:1513
LabelStmt * getStmt() const
Definition: Decl.h:378
bool isObviouslyBranchWithoutCleanups(JumpDest Dest) const
Definition: CGCleanup.cpp:915
void incrementProfileCounter(const Stmt *S)
Increment the profiler's counter for the given statement.
Expr * getCond()
Definition: Stmt.h:1177
void EmitStmt(const Stmt *S)
Definition: CGStmt.cpp:45
void EmitOMPParallelDirective(const OMPParallelDirective &S)
llvm::BasicBlock * createBasicBlock(const Twine &name="", llvm::Function *parent=nullptr, llvm::BasicBlock *before=nullptr)
createBasicBlock - Create an LLVM basic block.
void EmitIgnoredExpr(const Expr *E)
EmitIgnoredExpr - Emit an expression in a context which ignores the result.
Definition: CGExpr.cpp:107
llvm::Function * EmitCapturedStmt(const CapturedStmt &S, CapturedRegionKind K)
Definition: CGStmt.cpp:2177
bool requiresCleanups() const
Determine whether this scope requires any cleanups.
void EmitDefaultStmt(const DefaultStmt &S)
Definition: CGStmt.cpp:1300
static bool ContainsLabel(const Stmt *S, bool IgnoreCaseStmts=false)
const RecordDecl * getCapturedRecordDecl() const
Retrieve the record declaration for captured variables.
Definition: Stmt.h:2126
void EmitCaseStmtRange(const CaseStmt &S)
Definition: CGStmt.cpp:1139
This represents the body of a CapturedStmt, and serves as its DeclContext.
Definition: Decl.h:3616
LValue EmitLValueForField(LValue Base, const FieldDecl *Field)
Definition: CGExpr.cpp:2680
SourceLocation getAsmLoc() const
Definition: Stmt.h:1428
void EmitOMPParallelSectionsDirective(const OMPParallelSectionsDirective &S)
const TargetCodeGenInfo & getTargetCodeGenInfo()
Expr * IgnoreParenNoopCasts(ASTContext &Ctx) LLVM_READONLY
Definition: Expr.cpp:2559
virtual std::string convertConstraint(const char *&Constraint) const
ASTContext * Context
SourceLocation getBodyRBrace() const
Definition: DeclBase.cpp:693
std::string generateAsmString(const ASTContext &C) const
Assemble final IR asm string.
Definition: Stmt.cpp:328
SourceManager & SM
Exposes information about the current target.
virtual StringRef getHelperName() const
Get the name of the capture helper.
static TypeEvaluationKind getEvaluationKind(QualType T)
LabelDecl * getDecl() const
Definition: Stmt.h:809
bool empty() const
Determines whether the exception-scopes stack is empty.
Definition: EHScopeStack.h:327
const Expr * getInputExpr(unsigned i) const
Definition: Stmt.cpp:360
llvm::Value * GenerateCapturedStmtArgument(const CapturedStmt &S)
Definition: CGStmt.cpp:2193
bool isAggregate() const
Definition: CGValue.h:49
Enters a new scope for capturing cleanups, all of which will be executed once the scope is exited...
void EmitCaseStmt(const CaseStmt &S)
Definition: CGStmt.cpp:1217
VarDecl * getConditionVariable() const
Retrieve the variable declared in this "while" statement, if any.
Definition: Stmt.cpp:985
void EmitOMPTeamsDirective(const OMPTeamsDirective &S)
void SetInternalFunctionAttributes(const Decl *D, llvm::Function *F, const CGFunctionInfo &FI)
Stmt * getBody() const override
Definition: Decl.h:3640
LabelDecl * getConstantTarget()
Definition: Stmt.cpp:1005
bool haveRegionCounts() const
Definition: CodeGenPGO.h:53
Stmt * getBody()
Definition: Stmt.h:1069
void EmitSEHTryStmt(const SEHTryStmt &S)
ASTContext & getContext() const
Expr * getRHS()
Definition: Stmt.h:718
llvm::BasicBlock * getBlock() const
EHScopeStack::stable_iterator getScopeDepth() const
llvm::Value * EmitCompoundStmtWithoutScope(const CompoundStmt &S, bool GetLast=false, AggValueSlot AVS=AggValueSlot::ignored())
Definition: CGStmt.cpp:287
static llvm::MDNode * getAsmSrcLocInfo(const StringLiteral *Str, CodeGenFunction &CGF)
Definition: CGStmt.cpp:1786
stable_iterator stable_begin() const
Definition: EHScopeStack.h:364
llvm::LLVMContext & getLLVMContext()
llvm::BasicBlock * GetIndirectGotoBlock()
const SwitchCase * getSwitchCaseList() const
Definition: Stmt.h:987
void EmitOMPMasterDirective(const OMPMasterDirective &S)
bool EvaluateAsInt(llvm::APSInt &Result, const ASTContext &Ctx, SideEffectsKind AllowSideEffects=SE_NoSideEffects) const
llvm::Function * GenerateCapturedStmtFunction(const CapturedStmt &S)
Creates the outlined function for a CapturedStmt.
Definition: CGStmt.cpp:2200
LValue MakeNaturalAlignAddrLValue(llvm::Value *V, QualType T)
void ResolveBranchFixups(llvm::BasicBlock *Target)
Definition: CGCleanup.cpp:349
void EmitOMPBarrierDirective(const OMPBarrierDirective &S)
static CSFC_Result CollectStatementsForCase(const Stmt *S, const SwitchCase *Case, bool &FoundCase, SmallVectorImpl< const Stmt * > &ResultStmts)
Definition: CGStmt.cpp:1334
StringRef getInputConstraint(unsigned i) const
Definition: Stmt.cpp:352
ValueDecl * getDecl()
Definition: Expr.h:994
The result type of a method or function.
SourceLocation getLocationOfByte(unsigned ByteNo, const SourceManager &SM, const LangOptions &Features, const TargetInfo &Target) const
Definition: Expr.cpp:1006
void EmitDeclStmt(const DeclStmt &S)
Definition: CGStmt.cpp:1102
void EmitAnyExprToMem(const Expr *E, llvm::Value *Location, Qualifiers Quals, bool IsInitializer)
Definition: CGExpr.cpp:148
LabelDecl * getLabel() const
Definition: Stmt.h:1226
bool isNothrow() const
Definition: Decl.h:3643
void EmitOMPFlushDirective(const OMPFlushDirective &S)
CharUnits getTypeAlignInChars(QualType T) const
Return the ABI-specified alignment of a (complete) type T, in characters.
This captures a statement into a function. For example, the following pragma annotated compound state...
Definition: Stmt.h:1989
ASTContext & getContext() const
Encodes a location in the source. The SourceManager can decode this to get at the full include stack...
void EmitOMPForDirective(const OMPForDirective &S)
void EmitAggregateCopy(llvm::Value *DestPtr, llvm::Value *SrcPtr, QualType EltTy, bool isVolatile=false, CharUnits Alignment=CharUnits::Zero(), bool isAssignment=false)
Definition: CGExprAgg.cpp:1425
llvm::Value * EvaluateExprAsBool(const Expr *E)
Definition: CGExpr.cpp:91
Expr * getLHS()
Definition: Stmt.h:717
void EmitObjCForCollectionStmt(const ObjCForCollectionStmt &S)
Definition: CGObjC.cpp:1439
capture_init_iterator capture_init_end() const
Retrieve the iterator pointing one past the last initialization argument.
Definition: Stmt.h:2178
bool ConstantFoldsToSimpleInteger(const Expr *Cond, bool &Result)
An aggregate value slot.
Definition: CGValue.h:363
const Expr * getCond() const
Definition: Stmt.h:985
llvm::APSInt EvaluateKnownConstInt(const ASTContext &Ctx, SmallVectorImpl< PartialDiagnosticAt > *Diag=nullptr) const
param_iterator param_begin() const
Retrieve an iterator pointing to the first parameter decl.
Definition: Decl.h:3673
void EmitOMPTaskgroupDirective(const OMPTaskgroupDirective &S)
const CodeGenOptions & getCodeGenOpts() const
void EmitOMPSingleDirective(const OMPSingleDirective &S)
void StartFunction(GlobalDecl GD, QualType RetTy, llvm::Function *Fn, const CGFunctionInfo &FnInfo, const FunctionArgList &Args, SourceLocation Loc=SourceLocation(), SourceLocation StartLoc=SourceLocation())
Emit code for the start of a function.
const LangOptions & getLangOpts() const
VarDecl * getConditionVariable() const
Retrieve the variable declared in this "switch" statement, if any.
Definition: Stmt.cpp:951
llvm::AllocaInst * CreateMemTemp(QualType T, const Twine &Name="tmp")
Definition: CGExpr.cpp:80
void EmitOMPForSimdDirective(const OMPForSimdDirective &S)
void EmitOMPAtomicDirective(const OMPAtomicDirective &S)
JumpDest getJumpDestInCurrentScope(llvm::BasicBlock *Target)
void EmitOMPSectionDirective(const OMPSectionDirective &S)
virtual llvm::Type * adjustInlineAsmType(CodeGen::CodeGenFunction &CGF, StringRef Constraint, llvm::Type *Ty) const
void EmitOMPSectionsDirective(const OMPSectionsDirective &S)
void EmitForStmt(const ForStmt &S, ArrayRef< const Attr * > Attrs=None)
Definition: CGStmt.cpp:837
const CGFunctionInfo * CurFnInfo
void enterFullExpression(const ExprWithCleanups *E)
void EmitDecl(const Decl &D)
Definition: CGDecl.cpp:35
void FinishFunction(SourceLocation EndLoc=SourceLocation())
SourceLocation getExprLoc() const LLVM_READONLY
Definition: Expr.cpp:193
llvm::Value * EmitScalarExpr(const Expr *E, bool IgnoreResultAssign=false)
QualType getType() const
Definition: Expr.h:125
void EmitObjCAtSynchronizedStmt(const ObjCAtSynchronizedStmt &S)
Definition: CGObjC.cpp:1733
void ErrorUnsupported(const Stmt *S, const char *Type)
Print out an error that codegen doesn't support the specified stmt yet.
VarDecl * getConditionVariable() const
Retrieve the variable declared in this "if" statement, if any.
Definition: Stmt.cpp:894
bool isScalar() const
Definition: CGValue.h:47
void EmitOMPTaskyieldDirective(const OMPTaskyieldDirective &S)
LValue InitCapturedStruct(const CapturedStmt &S)
Definition: CGStmt.cpp:2150
const Stmt * getBody() const
Definition: Stmt.h:986
llvm::Value * getScalarVal() const
getScalarVal() - Return the Value* of this scalar value.
Definition: CGValue.h:54
void EmitOMPParallelForDirective(const OMPParallelForDirective &S)
CSFC_Result
Definition: CGStmt.cpp:1333
bool hasTiedOperand() const
Return true if this input operand is a matching constraint that ties it to an output operand...
StringRef getString() const
Definition: Expr.h:1521
void EmitOMPCancelDirective(const OMPCancelDirective &S)
const Expr * getRetValue() const
Definition: Stmt.cpp:1013
void EmitObjCAtThrowStmt(const ObjCAtThrowStmt &S)
Definition: CGObjC.cpp:1729
body_iterator body_begin()
Definition: Stmt.h:586
Stmt *const * const_body_iterator
Definition: Stmt.h:596
void EmitAggExpr(const Expr *E, AggValueSlot AS)
Definition: CGExprAgg.cpp:1403
const Stmt * getThen() const
Definition: Stmt.h:916
JumpDest ReturnBlock
ReturnBlock - Unified return block.
static bool hasAggregateEvaluationKind(QualType T)
API for captured statement code generation.
static std::string SimplifyConstraint(const char *Constraint, const TargetInfo &Target, SmallVectorImpl< TargetInfo::ConstraintInfo > *OutCons=nullptr)
Definition: CGStmt.cpp:1642
void EmitBlockWithFallThrough(llvm::BasicBlock *BB, const Stmt *S)
DeclStmt * getBeginEndStmt()
Definition: StmtCXX.h:151
void EmitStoreOfComplex(ComplexPairTy V, LValue dest, bool isInit)
EmitStoreOfComplex - Store a complex number into the specified l-value.
void EmitAsmStmt(const AsmStmt &S)
Definition: CGStmt.cpp:1811
static std::string AddVariableConstraints(const std::string &Constraint, const Expr &AsmExpr, const TargetInfo &Target, CodeGenModule &CGM, const AsmStmt &Stmt, const bool EarlyClobber)
Definition: CGStmt.cpp:1697
decl_range decls()
Definition: Stmt.h:497
bool isNRVOVariable() const
Determine whether this local variable can be used with the named return value optimization (NRVO)...
Definition: Decl.h:1202
bool isVolatile() const
Definition: Stmt.h:1434
Internal linkage, which indicates that the entity can be referred to from within the translation unit...
Definition: Linkage.h:33
SourceLocation getLocStart() const LLVM_READONLY
Definition: Stmt.h:2182
StringRef getClobber(unsigned i) const
Definition: Stmt.cpp:368
ImplicitParamDecl * getContextParam() const
Retrieve the parameter containing captured variables.
Definition: Decl.h:3658
void EmitBlock(llvm::BasicBlock *BB, bool IsFinished=false)
Definition: CGStmt.cpp:348
SourceManager & getSourceManager()
Definition: ASTContext.h:494
DeclStmt * getRangeStmt()
Definition: StmtCXX.h:150
void EmitStopPoint(const Stmt *S)
EmitStopPoint - Emit a debug stoppoint if we are emitting debug info.
Definition: CGStmt.cpp:35
ArrayRef< const Attr * > getAttrs() const
Definition: Stmt.h:863
Expr * getTarget()
Definition: Stmt.h:1266
param_iterator param_end() const
Retrieve an iterator one past the last parameter decl.
Definition: Decl.h:3675
void setCurrentStmt(const Stmt *S)
Definition: CodeGenPGO.h:76
Expr * getCond()
Definition: Stmt.h:1111
llvm::DenseMap< const VarDecl *, llvm::Value * > NRVOFlags
A mapping from NRVO variables to the flags used to indicate when the NRVO has been applied to this va...
DiagnosticsEngine & getDiags() const
void EmitIfStmt(const IfStmt &S)
Definition: CGStmt.cpp:520
void EmitBranch(llvm::BasicBlock *Block)
Definition: CGStmt.cpp:368
void EmitReturnStmt(const ReturnStmt &S)
Definition: CGStmt.cpp:1027
llvm::Type * ConvertType(QualType T)
LValue EmitLValue(const Expr *E)
Definition: CGExpr.cpp:831
const Expr * getCond() const
Definition: Stmt.h:914
CapturedRegionKind getCapturedRegionKind() const
Retrieve the captured region kind.
Definition: Stmt.h:2116
void EmitLabelStmt(const LabelStmt &S)
Definition: CGStmt.cpp:463
StringRef getNormalizedGCCRegisterName(StringRef Name) const
Returns the "normalized" GCC register name.
RValue EmitLoadOfLValue(LValue V, SourceLocation Loc)
Definition: CGExpr.cpp:1316
bool hasNormalCleanups() const
Determines whether there are any normal cleanups on the stack.
Definition: EHScopeStack.h:334
const StringRef Input
Defines the clang::TargetInfo interface.
void ForceCleanup()
Force the emission of cleanups now, instead of waiting until this object is destroyed.
capture_init_iterator capture_init_begin() const
Retrieve the first initialization argument.
Definition: Stmt.h:2172
CGCapturedStmtInfo * CapturedStmtInfo
bool validateInputConstraint(ConstraintInfo *OutputConstraints, unsigned NumOutputs, ConstraintInfo &info) const
stable_iterator getInnermostNormalCleanup() const
Definition: EHScopeStack.h:340
A reference to a declared variable, function, enum, etc. [C99 6.5.1p2].
Definition: Expr.h:899
static RValue get(llvm::Value *V)
Definition: CGValue.h:71
bool EmitSimpleStmt(const Stmt *S)
Definition: CGStmt.cpp:252
CapturedRegionKind
The different kinds of captured statement.
Definition: CapturedStmt.h:17
void EmitBranchThroughCleanup(JumpDest Dest)
Definition: CGCleanup.cpp:940
static AggValueSlot forAddr(llvm::Value *addr, CharUnits align, Qualifiers quals, IsDestructed_t isDestructed, NeedsGCBarriers_t needsGC, IsAliased_t isAliased, IsZeroed_t isZeroed=IsNotZeroed)
Definition: CGValue.h:424
static ApplyDebugLocation CreateEmpty(CodeGenFunction &CGF)
Definition: CGDebugInfo.h:542
Stmt * getSubStmt()
Definition: Stmt.h:812
DeclStmt * getLoopVarStmt()
Definition: StmtCXX.h:156
unsigned getNumClobbers() const
Definition: Stmt.h:1479
SourceLocation getLocation() const
Definition: DeclBase.h:372
void EmitObjCAtTryStmt(const ObjCAtTryStmt &S)
Definition: CGObjC.cpp:1725
void EmitWhileStmt(const WhileStmt &S, ArrayRef< const Attr * > Attrs=None)
Definition: CGStmt.cpp:687
virtual void addReturnRegisterOutputs(CodeGen::CodeGenFunction &CGF, CodeGen::LValue ReturnValue, std::string &Constraints, std::vector< llvm::Type * > &ResultRegTypes, std::vector< llvm::Type * > &ResultTruncRegTypes, std::vector< CodeGen::LValue > &ResultRegDests, std::string &AsmString, unsigned NumOutputs) const
Adds constraints and types for result registers.
void EmitBlockAfterUses(llvm::BasicBlock *BB)
Definition: CGStmt.cpp:385
void assignRegionCounters(const Decl *D, llvm::Function *Fn)
Definition: CodeGenPGO.cpp:660
void EmitBreakStmt(const BreakStmt &S)
Definition: CGStmt.cpp:1112
void EmitObjCAutoreleasePoolStmt(const ObjCAutoreleasePoolStmt &S)
Definition: CGObjC.cpp:2839
void push(llvm::BasicBlock *Header, llvm::ArrayRef< const Attr * > Attrs=llvm::None)
Begin a new structured loop. The set of staged attributes will be applied to the loop and then cleare...
Definition: CGLoopInfo.cpp:81
static bool containsBreak(const Stmt *S)
virtual bool hasBody() const
Returns true if this Decl represents a declaration for a body of code, such as a function or method d...
Definition: DeclBase.h:846
This class handles loading and caching of source files into memory.
Stmt * getSubStmt()
Definition: Stmt.h:866
void EmitOMPTaskDirective(const OMPTaskDirective &S)
void EmitCondBrHints(llvm::LLVMContext &Context, llvm::BranchInst *CondBr, ArrayRef< const Attr * > Attrs)
Definition: CGStmt.cpp:593
Attr - This represents one attribute.
Definition: Attr.h:44
virtual const char * getClobbers() const =0
Returns a string of target-specific clobbers, in LLVM format.
Stmt * getSubStmt()
Definition: Stmt.h:719
llvm::FunctionType * GetFunctionType(const CGFunctionInfo &Info)
GetFunctionType - Get the LLVM function type for.
Definition: CGCall.cpp:1253