[llvm] [AMDGPU] Lazily emit waitcnts on function entry (PR #73122)

[Diana Picus via llvm-commits]

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@@ -6,10 +6,12 @@ declare hidden ptr addrspace(1) @ext(ptr addrspace(1))
 define ptr addrspace(1) @call_assert_align() {
 ; CHECK-LABEL: call_assert_align:
 ; CHECK:       ; %bb.0: ; %entry
-; CHECK-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    s_waitcnt lgkmcnt(0)
 ; CHECK-NEXT:    s_mov_b32 s16, s33
 ; CHECK-NEXT:    s_mov_b32 s33, s32
+; CHECK-NEXT:    s_waitcnt expcnt(0)
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rovka wrote:

Why are we waiting for expcnt here? (as opposed to after changing EXEC)

https://github.com/llvm/llvm-project/pull/73122