[clang] [AMDGPU] Make `__GCC_DESTRUCTIVE_SIZE` 128 on AMDGPU (PR #115241)

[Matt Arsenault via cfe-commits]

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@@ -462,6 +462,10 @@ class LLVM_LIBRARY_VISIBILITY AMDGPUTargetInfo final : public TargetInfo {
   }
 
   bool hasHIPImageSupport() const override { return HasImage; }
+
+  std::pair<unsigned, unsigned> hardwareInterferenceSizes() const override {
+    return std::make_pair(128, 128);
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arsenm wrote:

Comment this is imprecise 

https://github.com/llvm/llvm-project/pull/115241