bool CodeGenPrepare::OptimizeCallInst(CallInst *CI) {
// Lower all uses of llvm.objectsize.*
IntrinsicInst *II = dyn_cast<IntrinsicInst>(CI);
if (II && II->getIntrinsicID() == Intrinsic::objectsize) {
bool Min = (cast<ConstantInt>(II->getArgOperand(1))->getZExtValue() == 1);
const Type *ReturnTy = CI->getType();
Constant *RetVal = ConstantInt::get(ReturnTy, Min ? 0 : -1ULL);
CI->replaceAllUsesWith(RetVal);
CI->eraseFromParent();
return true;
}
// From here on out we're working with named functions.
if (CI->getCalledFunction() == 0) return false;
// We'll need TargetData from here on out.
const TargetData *TD = TLI ? TLI->getTargetData() : 0;
if (!TD) return false;
// Lower all default uses of _chk calls. This is very similar
// to what InstCombineCalls does, but here we are only lowering calls
// that have the default "don't know" as the objectsize. Anything else
// should be left alone.
CodeGenPrepareFortifiedLibCalls Simplifier;
return Simplifier.fold(CI, TD);
}
bool CodeGenPrepare::OptimizeCallInst(CallInst *CI) {
BasicBlock *BB = CI->getParent();
// Lower inline assembly if we can.
// If we found an inline asm expession, and if the target knows how to
// lower it to normal LLVM code, do so now.
if (TLI && isa<InlineAsm>(CI->getCalledValue())) {
if (TLI->ExpandInlineAsm(CI)) {
// Avoid invalidating the iterator.
CurInstIterator = BB->begin();
// Avoid processing instructions out of order, which could cause
// reuse before a value is defined.
SunkAddrs.clear();
return true;
}
// Sink address computing for memory operands into the block.
if (OptimizeInlineAsmInst(CI))
return true;
}
// Lower all uses of llvm.objectsize.*
IntrinsicInst *II = dyn_cast<IntrinsicInst>(CI);
if (II && II->getIntrinsicID() == Intrinsic::objectsize) {
bool Min = (cast<ConstantInt>(II->getArgOperand(1))->getZExtValue() == 1);
Type *ReturnTy = CI->getType();
Constant *RetVal = ConstantInt::get(ReturnTy, Min ? 0 : -1ULL);
// Substituting this can cause recursive simplifications, which can
// invalidate our iterator. Use a WeakVH to hold onto it in case this
// happens.
WeakVH IterHandle(CurInstIterator);
ReplaceAndSimplifyAllUses(CI, RetVal, TLI ? TLI->getTargetData() : 0,
TLInfo, ModifiedDT ? 0 : DT);
// If the iterator instruction was recursively deleted, start over at the
// start of the block.
if (IterHandle != CurInstIterator) {
CurInstIterator = BB->begin();
SunkAddrs.clear();
}
return true;
}
// From here on out we're working with named functions.
if (CI->getCalledFunction() == 0) return false;
// We'll need TargetData from here on out.
const TargetData *TD = TLI ? TLI->getTargetData() : 0;
if (!TD) return false;
// Lower all default uses of _chk calls. This is very similar
// to what InstCombineCalls does, but here we are only lowering calls
// that have the default "don't know" as the objectsize. Anything else
// should be left alone.
CodeGenPrepareFortifiedLibCalls Simplifier;
return Simplifier.fold(CI, TD);
}