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

[Finn Plummer 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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inbelic wrote:

CHECK-EX _P_ will check for the expansion variant, whereas CHECK-EX _T_ is just used to check if the extension is emitted from the module

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