[llvm] Handle GEPs with negative offset and 'nuw' attribute (PR #117147)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,228 @@
+;RUN: llc  -stop-after="hexagon-isel"  < %s | FileCheck %s
+
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arsenm wrote:

This test is far too big 

https://github.com/llvm/llvm-project/pull/117147