[clang] [RFC][Clang][AMDGPU] Emit only delta target-features to reduce IR bloat (PR #176533)

[Matt Arsenault via cfe-commits]

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@@ -470,6 +470,10 @@ CODEGENOPT(EmitIEEENaNCompliantInsts, 1, 1, Benign)
 /// Expands s_waitcnt instructions to help PC-sampling profilers identify stalls.
 CODEGENOPT(AMDGPUExpandWaitcntProfiling, 1, 0, Benign)
 
+/// Emit full target-features attribute for AMDGPU (for testing). (AMDGPU Only)
+/// By default, only features that differ from the target CPU's defaults are emitted.
+CODEGENOPT(AMDGPUEmitFullTargetFeatures, 1, 0, Benign)
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arsenm wrote:

This should not be be an option. this should be the only mode supported 

https://github.com/llvm/llvm-project/pull/176533