[clang] [llvm] [HLSL][SPIRV][DXIL] Implement `dot4add_i8packed` intrinsic (PR #113623)

[Finn Plummer via cfe-commits]

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@@ -2527,6 +2640,11 @@ bool SPIRVInstructionSelector::selectIntrinsic(Register ResVReg,
   case Intrinsic::spv_udot:
   case Intrinsic::spv_sdot:
     return selectIntegerDot(ResVReg, ResType, I);
+  case Intrinsic::spv_dot4add_i8packed:
+    if (STI.canUseExtension(SPIRV::Extension::SPV_KHR_integer_dot_product) ||
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inbelic wrote:

Created for tracking here: https://github.com/llvm/llvm-project/issues/114632

https://github.com/llvm/llvm-project/pull/113623