[PATCH] D158463: [AMDGPU] Add IR-level pass to rewrite away address space 7

Mon Oct 30 18:24:58 PDT 2023

arsenm added inline comments.

================
Comment at: llvm/lib/Target/AMDGPU/AMDGPULowerBufferFatPointers.cpp:1175
+  if (IsVolatile)
+    Intr->setMetadata("amdgpu.volatile", MDNode::get(Ctx, {}));
+}
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krzysz00 wrote:
> arsenm wrote:
> > What is this for? The safer thing to do would be record not volatile in metadata 
> On the one hand, that'd make sense. On the other hand, are buffer loads and stores currently volatile (and so we'd have metadata marking them as non-volatile) or would volatile by default be a breaking semantics change?
> 
> The point of this was to not lose information.
Assuming volatile by default is always conservatively correct. Since you technically can drop metadata, relying on it to preserve knowledge of volatileness is risky 

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  https://reviews.llvm.org/D158463/new/

https://reviews.llvm.org/D158463