diff options
| -rw-r--r-- | include/llvm/Analysis/ScalarEvolutionExpander.h | 4 | ||||
| -rw-r--r-- | lib/Analysis/ScalarEvolutionExpander.cpp | 25 |
2 files changed, 20 insertions, 9 deletions
diff --git a/include/llvm/Analysis/ScalarEvolutionExpander.h b/include/llvm/Analysis/ScalarEvolutionExpander.h index 647a7dcf51..a8c03b2219 100644 --- a/include/llvm/Analysis/ScalarEvolutionExpander.h +++ b/include/llvm/Analysis/ScalarEvolutionExpander.h @@ -72,8 +72,8 @@ namespace llvm { public: /// SCEVExpander - Construct a SCEVExpander in "canonical" mode. explicit SCEVExpander(ScalarEvolution &se, const char *name) - : SE(se), IVName(name), IVIncInsertLoop(0), CanonicalMode(true), - Builder(se.getContext(), TargetFolder(se.TD)) {} + : SE(se), IVName(name), IVIncInsertLoop(0), IVIncInsertPos(0), + CanonicalMode(true), Builder(se.getContext(), TargetFolder(se.TD)) {} /// clear - Erase the contents of the InsertedExpressions map so that users /// trying to expand the same expression into multiple BasicBlocks or diff --git a/lib/Analysis/ScalarEvolutionExpander.cpp b/lib/Analysis/ScalarEvolutionExpander.cpp index 9f6063e56a..478f555fec 100644 --- a/lib/Analysis/ScalarEvolutionExpander.cpp +++ b/lib/Analysis/ScalarEvolutionExpander.cpp @@ -19,6 +19,7 @@ #include "llvm/LLVMContext.h" #include "llvm/Target/TargetData.h" #include "llvm/ADT/STLExtras.h" + using namespace llvm; /// ReuseOrCreateCast - Arrange for there to be a cast of V to Ty at IP, @@ -848,6 +849,8 @@ SCEVExpander::getAddRecExprPHILiterally(const SCEVAddRecExpr *Normalized, const Loop *L, const Type *ExpandTy, const Type *IntTy) { + assert(!IVIncInsertLoop || IVIncInsertPos && "Uninitialized insert position"); + // Reuse a previously-inserted PHI, if present. for (BasicBlock::iterator I = L->getHeader()->begin(); PHINode *PN = dyn_cast<PHINode>(I); ++I) @@ -872,13 +875,15 @@ SCEVExpander::getAddRecExprPHILiterally(const SCEVAddRecExpr *Normalized, // If any of the operands don't dominate the insert position, bail. // Addrec operands are always loop-invariant, so this can only happen // if there are instructions which haven't been hoisted. - for (User::op_iterator OI = IncV->op_begin()+1, - OE = IncV->op_end(); OI != OE; ++OI) - if (Instruction *OInst = dyn_cast<Instruction>(OI)) - if (!SE.DT->dominates(OInst, IVIncInsertPos)) { - IncV = 0; - break; - } + if (L == IVIncInsertLoop) { + for (User::op_iterator OI = IncV->op_begin()+1, + OE = IncV->op_end(); OI != OE; ++OI) + if (Instruction *OInst = dyn_cast<Instruction>(OI)) + if (!SE.DT->dominates(OInst, IVIncInsertPos)) { + IncV = 0; + break; + } + } if (!IncV) break; // Advance to the next instruction. @@ -920,6 +925,12 @@ SCEVExpander::getAddRecExprPHILiterally(const SCEVAddRecExpr *Normalized, Value *StartV = expandCodeFor(Normalized->getStart(), ExpandTy, L->getHeader()->begin()); + // StartV must be hoisted into L's preheader to dominate the new phi. + Instruction *StartI = dyn_cast<Instruction>(StartV); + assert(!StartI || SE.DT->properlyDominates(StartI->getParent(), + L->getHeader()) && ""); + (void)StartI; + // Expand code for the step value. Insert instructions right before the // terminator corresponding to the back-edge. Do this before creating the PHI // so that PHI reuse code doesn't see an incomplete PHI. If the stride is |