[llvm] [AMDGPU] Fix debug line table for MSG_DEALLOC_VGPRS optimization (PR #88924)

[Jay Foad via llvm-commits]

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@@ -0,0 +1,40 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
+# RUN: llc -mtriple=amdgcn -mcpu=gfx1100 -run-pass=si-insert-waitcnts -o - %s | FileCheck %s
+
+# Verify that si-insert-waitcnts copies debug locations from the s_endpgm to the
+# "dealloc vgprs" s_sendmsg. If these are not present, the debugger will be
+# unable to break at the end of the shader.
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jayfoad wrote:

Could you add something like this description to the commit message when you merge? I guess the problem is that when you set a source breakpoint at the end of the program, you want the debugger to put it before the sendmsg not after it, so the vgprs are still available??

https://github.com/llvm/llvm-project/pull/88924