[llvm] [AMDGPU] Fix LDS reporting for targets without CU mode (PR #223587)

[Shilei Tian via llvm-commits]

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@@ -15,6 +15,11 @@
 ; RUN: not llc -mtriple=amdgpu7.00-amd-amdhsa -filetype=null %s 2>&1 | FileCheck -check-prefix=ERROR-LIMIT64K %s
 ; RUN: not llc -mtriple=amdgpu6.00-amd-amdpal -filetype=null %s 2>&1 | FileCheck -check-prefix=ERROR-LIMIT32K %s
 
+; Pre-gfx10 has no WGP mode, so +cumode must not change the limit.
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shiltian wrote:

Yeah, I actually wondered what kind of mode before gfx10? How many SIMDs does a target support?

https://github.com/llvm/llvm-project/pull/223587