[llvm] [AMDGPU] Rewrite GFX12 SGPR hazard handling to dedicated pass (PR #118750)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,331 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
+# RUN: llc -mtriple=amdgcn -mcpu=gfx1200 -verify-machineinstrs -run-pass post-RA-hazard-rec,amdgpu-wait-sgpr-hazards -o - %s | FileCheck -check-prefix=GCN %s
+
+--- |
+  @mem = internal unnamed_addr addrspace(4) constant [4 x <4 x i32>] [<4 x i32> <i32 0, i32 0, i32 0, i32 0>, <4 x i32> <i32 0, i32 0, i32 0, i32 0>, <4 x i32> <i32 0, i32 0, i32 0, i32 0>, <4 x i32> <i32 0, i32 0, i32 0, i32 0>]
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arsenm wrote:

Dead global 

https://github.com/llvm/llvm-project/pull/118750