Do not insert trivially dead select instructions, which allows us to

potentially fold more in one pass.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16583 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2004-09-29 05:43:32 +00:00
parent 4e998b2fea
commit 0ed7f42c1b

View File

@ -753,10 +753,19 @@ bool llvm::SimplifyCFG(BasicBlock *BB) {
FalseSucc->removePredecessor(BI->getParent());
// Insert a new select instruction.
Value *NewRetVal = new SelectInst(BI->getCondition(), TrueValue,
FalseValue, "retval", BI);
Value *NewRetVal;
Value *BrCond = BI->getCondition();
if (TrueValue != FalseValue)
NewRetVal = new SelectInst(BrCond, TrueValue,
FalseValue, "retval", BI);
else
NewRetVal = TrueValue;
new ReturnInst(NewRetVal, BI);
BI->getParent()->getInstList().erase(BI);
if (BrCond->use_empty())
if (Instruction *BrCondI = dyn_cast<Instruction>(BrCond))
BrCondI->getParent()->getInstList().erase(BrCondI);
return true;
}
}