[llvm] [GISel][AArch64][AMDGPU][RISCV] Canonicalize (sub X, C) -> (add X, -C) (PR #114309)

[Matt Arsenault via llvm-commits]

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@@ -197,7 +197,7 @@ body: |
     %7:_(s8) = G_CONSTANT i8 1
     ; CHECK: [[T3:%[0-9]+]]:_(s8) = G_TRUNC [[T0]](s32)
     %8:_(s8) = G_SUB %2, %7
-    ; CHECK: [[T4:%[0-9]+]]:_(s8) = G_SUB [[T3]], {{.*}}
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arsenm wrote:

Test with the dropped NUW? 

https://github.com/llvm/llvm-project/pull/114309