[llvm] [AMDGPU] Fix computation of waves/EU maximum (PR #140921)

[Matt Arsenault via llvm-commits]

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@@ -200,3 +200,15 @@ entry:
   ret void
 }
 attributes #10 = {"amdgpu-flat-work-group-size"="256,256" "amdgpu-waves-per-eu"="2,2"}
+
+; Minimum 2 waves, maximum limited by LDS usage.
+; CHECK-LABEL: {{^}}empty_at_least_2_lds_limited:
+; CHECK: SGPRBlocks: 12
+; CHECK: VGPRBlocks: 12
+; CHECK: NumSGPRsForWavesPerEU: 102
+; CHECK: NumVGPRsForWavesPerEU: 49
+define amdgpu_kernel void @empty_at_least_2_lds_limited() #11 {
+entry:
+  ret void
+}
+attributes #11 = {"amdgpu-flat-work-group-size"="1,256" "amdgpu-waves-per-eu"="2" "amdgpu-lds-size"="16384"}
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arsenm wrote:

Can you add a copy where the attribute is fully specified with both min and max 

https://github.com/llvm/llvm-project/pull/140921