| ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py |
| ; Test CFG simplify removal of branch instructions. |
| ; |
| ; RUN: opt < %s -passes=simplifycfg -simplifycfg-require-and-preserve-domtree=1 -S | FileCheck %s |
| ; RUN: opt < %s -passes=simplifycfg -S | FileCheck %s |
| |
| define void @test1() { |
| ; CHECK-LABEL: @test1( |
| ; CHECK-NEXT: ret void |
| ; |
| br label %1 |
| ret void |
| } |
| |
| define void @test2() { |
| ; CHECK-LABEL: @test2( |
| ; CHECK-NEXT: ret void |
| ; |
| ret void |
| ret void |
| } |
| |
| define void @test3(i1 %T) { |
| ; CHECK-LABEL: @test3( |
| ; CHECK-NEXT: ret void |
| ; |
| br i1 %T, label %1, label %1 |
| ret void |
| } |
| |
| ; Folding branch to a common destination. |
| define void @test4_fold(i32 %a, i32 %b) { |
| ; CHECK-LABEL: @test4_fold( |
| ; CHECK-NEXT: [[CMP1:%.*]] = icmp eq i32 [[A:%.*]], [[B:%.*]] |
| ; CHECK-NEXT: [[CMP2:%.*]] = icmp ugt i32 [[A]], 0 |
| ; CHECK-NEXT: [[OR_COND:%.*]] = and i1 [[CMP1]], [[CMP2]] |
| ; CHECK-NEXT: br i1 [[OR_COND]], label [[ELSE:%.*]], label [[COMMON_RET:%.*]] |
| ; CHECK: common.ret: |
| ; CHECK-NEXT: ret void |
| ; CHECK: else: |
| ; CHECK-NEXT: call void @foo() |
| ; CHECK-NEXT: br label [[COMMON_RET]] |
| ; |
| %cmp1 = icmp eq i32 %a, %b |
| br i1 %cmp1, label %taken, label %untaken |
| |
| taken: |
| %cmp2 = icmp ugt i32 %a, 0 |
| br i1 %cmp2, label %else, label %untaken |
| |
| else: |
| call void @foo() |
| ret void |
| |
| untaken: |
| ret void |
| } |
| |
| ; Prefer a simplification based on a dominating condition rather than folding a |
| ; branch to a common destination. |
| define void @test4_no_fold(i32 %a, i32 %b) { |
| ; CHECK-LABEL: @test4_no_fold( |
| ; CHECK-NEXT: untaken: |
| ; CHECK-NEXT: [[CMP1:%.*]] = icmp eq i32 [[A:%.*]], [[B:%.*]] |
| ; CHECK-NEXT: ret void |
| ; |
| %cmp1 = icmp eq i32 %a, %b |
| br i1 %cmp1, label %taken, label %untaken |
| |
| taken: |
| %cmp2 = icmp ugt i32 %a, %b |
| br i1 %cmp2, label %else, label %untaken |
| |
| else: |
| call void @foo() |
| ret void |
| |
| untaken: |
| ret void |
| } |
| |
| declare void @foo() |
| |
| ; PR5795 |
| define void @test5(i32 %A) { |
| ; CHECK-LABEL: @test5( |
| ; CHECK-NEXT: common.ret: |
| ; CHECK-NEXT: ret void |
| ; |
| switch i32 %A, label %return [ |
| i32 2, label %1 |
| i32 10, label %2 |
| ] |
| |
| ret void |
| |
| ret void |
| |
| return: ; preds = %entry |
| ret void |
| } |
| |
| |
| ; PR14893 |
| define i8 @test6f() { |
| ; CHECK-LABEL: @test6f( |
| ; CHECK-NEXT: bb0: |
| ; CHECK-NEXT: [[R:%.*]] = alloca i8, align 1 |
| ; CHECK-NEXT: [[TMP:%.*]] = call i8 @test6g(ptr [[R]]) |
| ; CHECK-NEXT: [[TMP1:%.*]] = icmp eq i8 [[TMP]], 0 |
| ; CHECK-NEXT: [[TMP3:%.*]] = load i8, ptr [[R]], align 1 |
| ; CHECK-NEXT: [[TMP4:%.*]] = icmp eq i8 [[TMP3]], 1 |
| ; CHECK-NEXT: [[OR_COND:%.*]] = select i1 [[TMP1]], i1 true, i1 [[TMP4]] |
| ; CHECK-NEXT: [[TMP6:%.*]] = select i1 [[OR_COND]], i8 0, i8 1 |
| ; CHECK-NEXT: ret i8 [[TMP6]] |
| ; |
| |
| bb0: |
| %r = alloca i8, align 1 |
| %tmp = call i8 @test6g(ptr %r) |
| %tmp1 = icmp eq i8 %tmp, 0 |
| br i1 %tmp1, label %bb2, label %bb1 |
| bb1: |
| %tmp3 = load i8, ptr %r, align 1, !range !2, !tbaa !10, !dbg !5 |
| %tmp4 = icmp eq i8 %tmp3, 1 |
| br i1 %tmp4, label %bb2, label %bb3 |
| bb2: |
| br label %bb3 |
| bb3: |
| %tmp6 = phi i8 [ 0, %bb2 ], [ 1, %bb1 ] |
| ret i8 %tmp6 |
| } |
| declare i8 @test6g(ptr) |
| |
| !llvm.dbg.cu = !{!3} |
| !llvm.module.flags = !{!8, !9} |
| |
| !0 = !{!10, !10, i64 0} |
| !1 = !{!"foo"} |
| !2 = !{i8 0, i8 2} |
| !3 = distinct !DICompileUnit(language: DW_LANG_C99, file: !7, producer: "clang", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !4, globals: !4) |
| !4 = !{} |
| !5 = !DILocation(line: 23, scope: !6) |
| !6 = distinct !DISubprogram(name: "foo", scope: !3, file: !7, line: 1, type: !DISubroutineType(types: !4), isLocal: false, isDefinition: true, scopeLine: 1, flags: DIFlagPrototyped, isOptimized: false, unit: !3, retainedNodes: !4) |
| !7 = !DIFile(filename: "foo.c", directory: "/") |
| !8 = !{i32 2, !"Dwarf Version", i32 2} |
| !9 = !{i32 2, !"Debug Info Version", i32 3} |
| !10 = !{!"scalar type", !1} |