Factor checked library call optimization into a common helper class and use it
to unify the almost identical code in CodeGenPrepare and InstCombineCalls.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98338 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/CodeGenPrepare.cpp b/lib/Transforms/Scalar/CodeGenPrepare.cpp
index c26d74d..50c9630 100644
--- a/lib/Transforms/Scalar/CodeGenPrepare.cpp
+++ b/lib/Transforms/Scalar/CodeGenPrepare.cpp
@@ -540,9 +540,22 @@
return MadeChange;
}
+namespace {
+class CodeGenPrepareFortifiedLibCalls : public SimplifyFortifiedLibCalls {
+protected:
+ void replaceCall(Value *With) {
+ CI->replaceAllUsesWith(With);
+ CI->eraseFromParent();
+ }
+ bool isFoldable(unsigned SizeCIOp, unsigned, bool) const {
+ if (ConstantInt *SizeCI = dyn_cast<ConstantInt>(CI->getOperand(SizeCIOp)))
+ return SizeCI->isAllOnesValue();
+ return false;
+ }
+};
+} // end anonymous namespace
+
bool CodeGenPrepare::OptimizeCallInst(CallInst *CI) {
- bool MadeChange = false;
-
// Lower all uses of llvm.objectsize.*
IntrinsicInst *II = dyn_cast<IntrinsicInst>(CI);
if (II && II->getIntrinsicID() == Intrinsic::objectsize) {
@@ -561,102 +574,12 @@
const TargetData *TD = TLI ? TLI->getTargetData() : 0;
if (!TD) return false;
- // Lower all default uses of _chk calls. This is code very similar
- // to the code in InstCombineCalls, but here we are only lowering calls
+ // 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.
- StringRef Name = CI->getCalledFunction()->getName();
- BasicBlock *BB = CI->getParent();
- IRBuilder<> B(CI->getParent()->getContext());
-
- // Set the builder to the instruction after the call.
- B.SetInsertPoint(BB, CI);
-
- if (Name == "__memcpy_chk") {
- ConstantInt *SizeCI = dyn_cast<ConstantInt>(CI->getOperand(4));
- if (!SizeCI)
- return 0;
- if (SizeCI->isAllOnesValue()) {
- EmitMemCpy(CI->getOperand(1), CI->getOperand(2), CI->getOperand(3),
- 1, B, TD);
- CI->replaceAllUsesWith(CI->getOperand(1));
- CI->eraseFromParent();
- return true;
- }
- return 0;
- }
-
- // Should be similar to memcpy.
- if (Name == "__mempcpy_chk") {
- return 0;
- }
-
- if (Name == "__memmove_chk") {
- ConstantInt *SizeCI = dyn_cast<ConstantInt>(CI->getOperand(4));
- if (!SizeCI)
- return 0;
- if (SizeCI->isAllOnesValue()) {
- EmitMemMove(CI->getOperand(1), CI->getOperand(2), CI->getOperand(3),
- 1, B, TD);
- CI->replaceAllUsesWith(CI->getOperand(1));
- CI->eraseFromParent();
- return true;
- }
- return 0;
- }
-
- if (Name == "__memset_chk") {
- ConstantInt *SizeCI = dyn_cast<ConstantInt>(CI->getOperand(4));
- if (!SizeCI)
- return 0;
- if (SizeCI->isAllOnesValue()) {
- Value *Val = B.CreateIntCast(CI->getOperand(2), B.getInt8Ty(),
- false);
- EmitMemSet(CI->getOperand(1), Val, CI->getOperand(3), B, TD);
- CI->replaceAllUsesWith(CI->getOperand(1));
- CI->eraseFromParent();
- return true;
- }
- return 0;
- }
-
- if (Name == "__strcpy_chk" || Name == "__stpcpy_chk") {
- ConstantInt *SizeCI = dyn_cast<ConstantInt>(CI->getOperand(3));
- if (!SizeCI)
- return 0;
- if (SizeCI->isAllOnesValue()) {
- Value *Ret = EmitStrCpy(CI->getOperand(1), CI->getOperand(2), B, TD,
- Name.substr(2, 6));
- CI->replaceAllUsesWith(Ret);
- CI->eraseFromParent();
- return true;
- }
- return 0;
- }
-
- if (Name == "__strncpy_chk") {
- ConstantInt *SizeCI = dyn_cast<ConstantInt>(CI->getOperand(4));
- if (!SizeCI)
- return 0;
- if (SizeCI->isAllOnesValue()) {
- Value *Ret = EmitStrNCpy(CI->getOperand(1), CI->getOperand(2),
- CI->getOperand(3), B, TD);
- CI->replaceAllUsesWith(Ret);
- CI->eraseFromParent();
- return true;
- }
- return 0;
- }
-
- if (Name == "__strcat_chk") {
- return 0;
- }
-
- if (Name == "__strncat_chk") {
- return 0;
- }
-
- return MadeChange;
+ CodeGenPrepareFortifiedLibCalls Simplifier;
+ return Simplifier.fold(CI, TD);
}
//===----------------------------------------------------------------------===//
// Memory Optimization