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

[Greg Roth via cfe-commits]

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@@ -0,0 +1,65 @@
+; RUN: llc -O0 -mtriple=spirv1.5-unknown-unknown %s -o - | FileCheck %s --check-prefixes=CHECK,CHECK-EXP
+; RUN: llc -O0 -mtriple=spirv1.6-unknown-unknown %s -o - | FileCheck %s --check-prefixes=CHECK,CHECK-DOT
+; RUN: llc -O0 -mtriple=spirv-unknown-unknown -spirv-ext=+SPV_KHR_integer_dot_product %s -o - | FileCheck %s --check-prefixes=CHECK,CHECK-DOT,CHECK-EXT
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pow2clk wrote:

I see this in the existing test as well. Perhaps you can remind me why we can expect both the integer dot product operations as well as the expansion in this case? 

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