[clang] [llvm] [HLSL][DXIL][SPIRV] Create llvm dot intrinsic and use for HLSL (PR #102872)

[Farzon Lotfi via cfe-commits]

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@@ -18470,22 +18470,14 @@ llvm::Value *CodeGenFunction::EmitScalarOrConstFoldImmArg(unsigned ICEArguments,
   return Arg;
 }
 
-Intrinsic::ID getDotProductIntrinsic(QualType QT, int elementCount) {
-  if (QT->hasFloatingRepresentation()) {
-    switch (elementCount) {
-    case 2:
-      return Intrinsic::dx_dot2;
-    case 3:
-      return Intrinsic::dx_dot3;
-    case 4:
-      return Intrinsic::dx_dot4;
-    }
-  }
-  if (QT->hasSignedIntegerRepresentation())
-    return Intrinsic::dx_sdot;
-
-  assert(QT->hasUnsignedIntegerRepresentation());
-  return Intrinsic::dx_udot;
+// Return dot product intrinsic that corresponds to the QT scalar type
+Intrinsic::ID getDotProductIntrinsic(QualType QT) {
+  if (QT->isFloatingType())
+    return Intrinsic::fdot;
+  if (QT->isSignedIntegerType())
+    return Intrinsic::sdot;
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farzonl wrote:

hmm rereading kparzysz  posts in the rfc and seeing aarch64 wants integer dot seems like my comment here isn't correct. I still feel weird about it because our usages of it don't lower to a specific opcode in either the SPIRV or DXIL backends.

https://github.com/llvm/llvm-project/pull/102872