[llvm] [AMDGPU][SplitKit] Skip any uses that are placed before the current block (PR #177270)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,86 @@
+; REQUIRES: asserts
+;
+; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx1201 -O1 < %s -o /dev/null
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arsenm wrote:

Should generate checks 

https://github.com/llvm/llvm-project/pull/177270