[llvm] [AMDGPU] Create local KnownBits in case DenseMap gets invalidated (PR #111568)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,120 @@
+; REQUIRES: asserts
+; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx1030 -o - %s 2>&1 | FileCheck %s
+
+; CHECK-NOT: Assertion `BitWidth == RHS.BitWidth && "Bit widths must be same for comparison"' failed
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arsenm wrote:

A check-not of an assert message is next to worthless, positively check the output 

https://github.com/llvm/llvm-project/pull/111568