[llvm] [DAG] Fold (umin (sub a b) a) -> (usubo a b); (select usubo.1 a usubo.0) (PR #161651)

[Simon Pilgrim via llvm-commits]

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@@ -0,0 +1,16 @@
+; RUN: llc < %s -mtriple=x86_64 | FileCheck %s
+
+; GitHub issue #161036
+
+define i64 @subIfNoUnderflow_umin(i64 %a, i64 %b) {
+; CHECK-LABEL: subIfNoUnderflow_umin
+; CHECK-LABEL: %bb.0
+; CHECK-NEXT: movq    %rdi, %rax
+; CHECK-NEXT: subq    %rsi, %rax
+; CHECK-NEXT: cmovbq  %rdi, %rax
+; CHECK-NEXT: retq
+entry:
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RKSimon wrote:

(style) remove entry

https://github.com/llvm/llvm-project/pull/161651