[clang] [llvm] [HLSL][SPIRV][DXIL] Implement `dot4add_u8packed` intrinsic (PR #115068)

[Finn Plummer via cfe-commits]

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@@ -1743,7 +1743,7 @@ bool SPIRVInstructionSelector::selectDot4AddPackedExpansion(
   assert(I.getOperand(4).isReg());
   MachineBasicBlock &BB = *I.getParent();
 
-  bool Result = false;
+  bool Result = true;
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inbelic wrote:

Good idea. It would be probably also be a good idea to audit the other uses of `Result |=` in the file, as I think there are other instances it was mistakenly used. I will create a new pr with those and this in it.

https://github.com/llvm/llvm-project/pull/115068