[clang] [llvm] [clang][SPIR-V] Add support for AMDGCN flavoured SPIRV (PR #89796)

[Alex Voicu via cfe-commits]

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@@ -1,4 +1,5 @@
 ; RUN: llc -O0 -mtriple=spirv64-unknown-unknown %s -o - | FileCheck %s
+; RUN: llc -O0 -mtriple=spirv64-amd-amdhsa %s -o - | FileCheck %s
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AlexVlx wrote:

I've rolled back most of these, except for a couple of places where there is a substantive difference (`spirv64-amdgcn-amdhsa` encodes the program address space in its DL, which yields slightly different IR in places).

https://github.com/llvm/llvm-project/pull/89796