diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Analysis/ScalarEvolutionExpander.cpp | 30 |
1 files changed, 15 insertions, 15 deletions
diff --git a/lib/Analysis/ScalarEvolutionExpander.cpp b/lib/Analysis/ScalarEvolutionExpander.cpp index a241960..9872ced 100644 --- a/lib/Analysis/ScalarEvolutionExpander.cpp +++ b/lib/Analysis/ScalarEvolutionExpander.cpp @@ -73,7 +73,7 @@ Value *SCEVExpander::InsertCastOfTo(Instruction::CastOps opcode, Value *V, /// InsertBinop - Insert the specified binary operator, doing a small amount /// of work to avoid inserting an obviously redundant operation. Value *SCEVExpander::InsertBinop(Instruction::BinaryOps Opcode, Value *LHS, - Value *RHS, Instruction *&InsertPt) { + Value *RHS, Instruction *InsertPt) { // Fold a binop with constant operands. if (Constant *CLHS = dyn_cast<Constant>(LHS)) if (Constant *CRHS = dyn_cast<Constant>(RHS)) @@ -81,21 +81,21 @@ Value *SCEVExpander::InsertBinop(Instruction::BinaryOps Opcode, Value *LHS, // Do a quick scan to see if we have this binop nearby. If so, reuse it. unsigned ScanLimit = 6; - for (BasicBlock::iterator IP = InsertPt, E = InsertPt->getParent()->begin(); - ScanLimit; --IP, --ScanLimit) { - if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(IP)) - if (BinOp->getOpcode() == Opcode && BinOp->getOperand(0) == LHS && - BinOp->getOperand(1) == RHS) { - // If we found the instruction *at* the insert point, insert later - // instructions after it. - if (BinOp == InsertPt) - InsertPt = ++IP; - return BinOp; - } - if (IP == E) break; + BasicBlock::iterator BlockBegin = InsertPt->getParent()->begin(); + if (InsertPt != BlockBegin) { + // Scanning starts from the last instruction before InsertPt. + BasicBlock::iterator IP = InsertPt; + --IP; + for (; ScanLimit; --IP, --ScanLimit) { + if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(IP)) + if (BinOp->getOpcode() == Opcode && BinOp->getOperand(0) == LHS && + BinOp->getOperand(1) == RHS) + return BinOp; + if (IP == BlockBegin) break; + } } - - // If we don't have + + // If we haven't found this binop, insert it. return BinaryOperator::Create(Opcode, LHS, RHS, "tmp", InsertPt); } |