[clang] [llvm] [DXIL] `exp`, `any`, `lerp`, & `rcp` Intrinsic Lowering (PR #84526)

[Justin Bogner via llvm-commits]

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@@ -18015,38 +18015,11 @@ Value *CodeGenFunction::EmitHLSLBuiltinExpr(unsigned BuiltinID,
     Value *X = EmitScalarExpr(E->getArg(0));
     Value *Y = EmitScalarExpr(E->getArg(1));
     Value *S = EmitScalarExpr(E->getArg(2));
-    llvm::Type *Xty = X->getType();
-    llvm::Type *Yty = Y->getType();
-    llvm::Type *Sty = S->getType();
-    if (!Xty->isVectorTy() && !Yty->isVectorTy() && !Sty->isVectorTy()) {
-      if (Xty->isFloatingPointTy()) {
-        auto V = Builder.CreateFSub(Y, X);
-        V = Builder.CreateFMul(S, V);
-        return Builder.CreateFAdd(X, V, "dx.lerp");
-      }
-      llvm_unreachable("Scalar Lerp is only supported on floats.");
-    }
-    // A VectorSplat should have happened
-    assert(Xty->isVectorTy() && Yty->isVectorTy() && Sty->isVectorTy() &&
-           "Lerp of vector and scalar is not supported.");
-
-    [[maybe_unused]] auto *XVecTy =
-        E->getArg(0)->getType()->getAs<VectorType>();
-    [[maybe_unused]] auto *YVecTy =
-        E->getArg(1)->getType()->getAs<VectorType>();
-    [[maybe_unused]] auto *SVecTy =
-        E->getArg(2)->getType()->getAs<VectorType>();
-    // A HLSLVectorTruncation should have happend
-    assert(XVecTy->getNumElements() == YVecTy->getNumElements() &&
-           XVecTy->getNumElements() == SVecTy->getNumElements() &&
-           "Lerp requires vectors to be of the same size.");
-    assert(XVecTy->getElementType()->isRealFloatingType() &&
-           XVecTy->getElementType() == YVecTy->getElementType() &&
-           XVecTy->getElementType() == SVecTy->getElementType() &&
-           "Lerp requires float vectors to be of the same type.");
+    if (!E->getArg(0)->getType()->hasFloatingRepresentation())
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bogner wrote:

Probably clearer to use `X` here rather than repeating `E->getArg(0)`

https://github.com/llvm/llvm-project/pull/84526