[llvm] [AMDGPU] Set SGPR spill stack IDs when creating spill slots (PR #197628)

[via llvm-commits]

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@@ -0,0 +1,62 @@
+; RUN: llc -O1 -mtriple=amdgcn-amd-amdhsa -mcpu=gfx90a -verify-machineinstrs -o - %s > /dev/null
+
+define void @sgpr_scavenge_fi_stack_id(double %arg, i1 %outer.cond, i1 %exit.cond, i1 %middle.cond, i1 %inner.cond, i1 %loop.break.cond, ptr addrspace(5) %out, i1 %select.cond) {
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woruyu wrote:

understand! I have deleted `-o -` and removed unused attribute. However, this case is very sensitive to SGPR register pressure and is difficult to simplify.

https://github.com/llvm/llvm-project/pull/197628