[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:

No. It just introduces the flags, which may or may not survive to the end of the target's selection 

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