[llvm] [AMDGPU] Support partial and empty WWM pools for SGPR spills (PR #213491)

[Matt Arsenault via llvm-commits]

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+# RUN: split-file %s %t
+# RUN: not llc -mtriple=amdgpu9.00-amd-amdhsa -amdgpu-stress-vgpr=1 -amdgpu-num-vgprs-for-wwm-alloc=2 -run-pass=si-lower-sgpr-spills -o /dev/null %t/strict.mir 2>&1 | FileCheck %s
+# RUN: not llc -mtriple=amdgpu9.00-amd-amdhsa -amdgpu-stress-vgpr=1 -amdgpu-num-vgprs-for-wwm-alloc=2 -amdgpu-prealloc-sgpr-spill-vgprs -run-pass=si-lower-sgpr-spills -o /dev/null %t/option.mir 2>&1 | FileCheck %s
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arsenm wrote:

-filetype=null 

https://github.com/llvm/llvm-project/pull/213491