[llvm] [InstCombine] Fold `(icmp eq/ne (xor x, y), C1)` even if multiuse (PR #87275)

[via llvm-commits]

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@@ -3698,7 +3698,8 @@ exit:
 define i32 @src_select_xxory_eq0_xorxy_y(i32 %x, i32 %y) {
 ; CHECK-LABEL: @src_select_xxory_eq0_xorxy_y(
 ; CHECK-NEXT:    [[XOR0:%.*]] = icmp eq i32 [[X:%.*]], [[Y:%.*]]
-; CHECK-NEXT:    [[COND:%.*]] = select i1 [[XOR0]], i32 0, i32 [[Y]]
+; CHECK-NEXT:    [[XOR:%.*]] = select i1 [[XOR0]], i32 [[X]], i32 0
+; CHECK-NEXT:    [[COND:%.*]] = xor i32 [[XOR]], [[Y]]
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goldsteinn wrote:

This should be cleaned up by: https://github.com/llvm/llvm-project/pull/73362

https://github.com/llvm/llvm-project/pull/87275