forked from OSchip/llvm-project
133 lines
3.0 KiB
LLVM
133 lines
3.0 KiB
LLVM
; Test CFG simplify removal of branch instructions.
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;
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; RUN: opt < %s -simplifycfg -S | FileCheck %s
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; RUN: opt < %s -passes=simplify-cfg -S | FileCheck %s
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define void @test1() {
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br label %1
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ret void
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; CHECK-LABEL: @test1(
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; CHECK-NEXT: ret void
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}
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define void @test2() {
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ret void
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ret void
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; CHECK-LABEL: @test2(
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; CHECK-NEXT: ret void
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; CHECK-NEXT: }
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}
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define void @test3(i1 %T) {
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br i1 %T, label %1, label %1
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ret void
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; CHECK-LABEL: @test3(
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; CHECK-NEXT: ret void
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}
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; Folding branch to a common destination.
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; CHECK-LABEL: @test4_fold
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; CHECK: %cmp1 = icmp eq i32 %a, %b
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; CHECK: %cmp2 = icmp ugt i32 %a, 0
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; CHECK: %or.cond = and i1 %cmp1, %cmp2
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; CHECK: br i1 %or.cond, label %else, label %untaken
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; CHECK-NOT: taken:
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; CHECK: ret void
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define void @test4_fold(i32 %a, i32 %b) {
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%cmp1 = icmp eq i32 %a, %b
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br i1 %cmp1, label %taken, label %untaken
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taken:
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%cmp2 = icmp ugt i32 %a, 0
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br i1 %cmp2, label %else, label %untaken
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else:
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call void @foo()
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ret void
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untaken:
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ret void
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}
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; Prefer a simplification based on a dominating condition rather than folding a
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; branch to a common destination.
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; CHECK-LABEL: @test4
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; CHECK-NOT: br
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; CHECK-NOT: br
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; CHECK-NOT: call
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; CHECK: ret void
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define void @test4_no_fold(i32 %a, i32 %b) {
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%cmp1 = icmp eq i32 %a, %b
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br i1 %cmp1, label %taken, label %untaken
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taken:
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%cmp2 = icmp ugt i32 %a, %b
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br i1 %cmp2, label %else, label %untaken
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else:
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call void @foo()
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ret void
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untaken:
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ret void
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}
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declare void @foo()
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; PR5795
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define void @test5(i32 %A) {
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switch i32 %A, label %return [
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i32 2, label %1
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i32 10, label %2
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]
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ret void
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ret void
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return: ; preds = %entry
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ret void
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; CHECK-LABEL: @test5(
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; CHECK-NEXT: ret void
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}
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; PR14893
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define i8 @test6f() {
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; CHECK-LABEL: @test6f
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; CHECK: alloca i8, align 1
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; CHECK-NEXT: call i8 @test6g
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; CHECK-NEXT: icmp eq i8 %tmp, 0
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; CHECK-NEXT: load i8, i8* %r, align 1, !dbg !{{[0-9]+$}}
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bb0:
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%r = alloca i8, align 1
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%tmp = call i8 @test6g(i8* %r)
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%tmp1 = icmp eq i8 %tmp, 0
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br i1 %tmp1, label %bb2, label %bb1
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bb1:
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%tmp3 = load i8, i8* %r, align 1, !range !2, !tbaa !1, !dbg !5
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%tmp4 = icmp eq i8 %tmp3, 1
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br i1 %tmp4, label %bb2, label %bb3
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bb2:
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br label %bb3
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bb3:
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%tmp6 = phi i8 [ 0, %bb2 ], [ 1, %bb1 ]
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ret i8 %tmp6
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}
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declare i8 @test6g(i8*)
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!llvm.dbg.cu = !{!3}
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!llvm.module.flags = !{!8, !9}
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!0 = !{!1, !1, i64 0}
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!1 = !{!"foo"}
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!2 = !{i8 0, i8 2}
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!3 = distinct !DICompileUnit(language: DW_LANG_C99, file: !7, producer: "clang", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !4, globals: !4)
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!4 = !{}
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!5 = !DILocation(line: 23, scope: !6)
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!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, variables: !4)
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!7 = !DIFile(filename: "foo.c", directory: "/")
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!8 = !{i32 2, !"Dwarf Version", i32 2}
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!9 = !{i32 2, !"Debug Info Version", i32 3}
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