[llvm] [AMDGPU][Draft] OOB mode - module flag (PR #160922)

[Krzysztof Drewniak via llvm-commits]

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@@ -291,6 +290,17 @@ class GCNSubtarget final : public AMDGPUGenSubtargetInfo,
   // Dummy feature to use for assembler in tablegen.
   bool FeatureDisable = false;
 
+  // Module flag features.
+
+  // Out-Of-Bounds mode flags.
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krzysz00 wrote:

Ok, so

1. There should be a bit flags enum here
2. I think you'll want to somewhere define the module linking behavior - I forget the exact mechanism for this, but I'm pretty sure there is one - such that a relaxed module linked to a strict module is strict (This might require two separate flags for untyped and typed buffers)
3. As a general thought, defaulting to strict mode in HIP code will make a lot of compute people suddenly unhappy with their performance drops (especially once we actually implement it into lower-buffer-fat-pointers). So we'll want to communicate this change pretty well

https://github.com/llvm/llvm-project/pull/160922