[llvm] [AMDGPU] Defaults for missing dimensions in SYCL required wg size (PR #68872)

[Matt Arsenault via llvm-commits]

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@@ -317,10 +317,38 @@ static bool processUse(CallInst *CI, bool IsV5OrAbove) {
   return MadeChange;
 }
 
+// SYCL allows required work-group size attribute to be partially specified
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arsenm wrote:

That sounds like a source syntax difference, clang could still emit consistent metadata with 1 padding. The IR doesn't need to 1:1 correspond to what the source looks like

If we really needed to support 2 forms of the metadata, I would expect to just have a utility function to read the effective value. You don't need to rewrite it

https://github.com/llvm/llvm-project/pull/68872