1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py 2; The unify-function-exit-nodes pass often makes basic blocks that just contain 3; a PHI node and a return. Make sure the simplify cfg can straighten out this 4; important case. This is basically the most trivial form of tail-duplication. 5 6; RUN: opt < %s -passes=simplifycfg -simplifycfg-require-and-preserve-domtree=1 -hoist-common-insts=true -S | FileCheck %s 7 8define i32 @test(i1 %B, i32 %A, i32 %B.upgrd.1) { 9; CHECK-LABEL: @test( 10; CHECK-NEXT: ret: 11; CHECK-NEXT: [[B_UPGRD_1_A:%.*]] = select i1 [[B:%.*]], i32 [[B_UPGRD_1:%.*]], i32 [[A:%.*]] 12; CHECK-NEXT: ret i32 [[B_UPGRD_1_A]] 13; 14 br i1 %B, label %T, label %F 15T: ; preds = %0 16 br label %ret 17F: ; preds = %0 18 br label %ret 19ret: ; preds = %F, %T 20 %X = phi i32 [ %A, %F ], [ %B.upgrd.1, %T ] ; <i32> [#uses=1] 21 ret i32 %X 22} 23 24 25; Make sure it's willing to move unconditional branches to return instructions 26; as well, even if the return block is shared and the source blocks are 27; non-empty. 28define i32 @test2(i1 %B, i32 %A, i32 %B.upgrd.2) { 29; CHECK-LABEL: @test2( 30; CHECK-NEXT: ret: 31; CHECK-NEXT: [[TMP0:%.*]] = call i32 @test(i1 true, i32 5, i32 8) 32; CHECK-NEXT: ret i32 [[A:%.*]] 33; 34 br i1 %B, label %T, label %F 35T: ; preds = %0 36 call i32 @test( i1 true, i32 5, i32 8 ) ; <i32>:1 [#uses=0] 37 br label %ret 38F: ; preds = %0 39 call i32 @test( i1 true, i32 5, i32 8 ) ; <i32>:2 [#uses=0] 40 br label %ret 41ret: ; preds = %F, %T 42 ret i32 %A 43} 44