[llvm] DAG: Preserve more flags when expanding gep (PR #110815)

[Matt Arsenault via llvm-commits]

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@@ -12,7 +12,7 @@ define void @pointer_add_unknown_offset(ptr %base, i32 %offset) !dbg !7 {
   ; CHECK-NEXT:   [[COPY:%[0-9]+]]:i64regs = COPY $i1
   ; CHECK-NEXT:   [[COPY1:%[0-9]+]]:i64regs = COPY $i0
   ; CHECK-NEXT:   [[SRAri:%[0-9]+]]:i64regs = SRAri [[COPY]], 0
-  ; CHECK-NEXT:   [[SLLXri:%[0-9]+]]:i64regs = SLLXri killed [[SRAri]], 2
+  ; CHECK-NEXT:   [[SLLXri:%[0-9]+]]:i64regs = nsw SLLXri killed [[SRAri]], 2
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arsenm wrote:

This test change is incidental, this test was not the point. The real tests are supposed to be from 671cbcf6420a9dfc81754d8dc683619f6f396ed8 (but in the final version of the patch, the codegen changes no longer manifest)

https://github.com/llvm/llvm-project/pull/110815