[clang] [llvm] Add length HLSL function to DirectX Backend (PR #101256)
Farzon Lotfi via cfe-commits
cfe-commits at lists.llvm.org
Tue Jul 30 15:45:12 PDT 2024
================
@@ -157,6 +158,42 @@ static bool expandAnyIntrinsic(CallInst *Orig) {
return true;
}
+static bool expandLengthIntrinsic(CallInst *Orig) {
+ Value *X = Orig->getOperand(0);
+ IRBuilder<> Builder(Orig->getParent());
+ Builder.SetInsertPoint(Orig);
+ Type *Ty = X->getType();
+ Type *EltTy = Ty->getScalarType();
+
+ // Though dx.length does work on scalar type, we can optimize it to just emit
+ // fabs, in CGBuiltin.cpp. We shouldn't see a scalar type here because
+ // CGBuiltin.cpp should have emitted a fabs call.
+ assert(Ty->isVectorTy() && "dx.length only works on vector type");
+ Value *Elt = Builder.CreateExtractElement(X, (uint64_t)0);
+ auto *XVec = dyn_cast<FixedVectorType>(Ty);
+ unsigned size = XVec->getNumElements();
+ if (size > 1) {
----------------
farzonl wrote:
I don't think we will evert get a vector of size 1, that should just be a scalar which you have an assert for so I would delete this if statement. If you are really concerned you can add the size check to your assert. But whatever you decide delete the if.
https://github.com/llvm/llvm-project/pull/101256
More information about the cfe-commits
mailing list