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https://github.com/RPCS3/llvm-mirror.git
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83c1a62e0a
Summary: If P branches to Q conditional on C and Q branches to R conditional on C' and C => C' then the branch conditional on C' can be folded to an unconditional branch. Reviewers: reames Subscribers: llvm-commits Differential Revision: http://reviews.llvm.org/D13972 llvm-svn: 251557
99 lines
2.1 KiB
LLVM
99 lines
2.1 KiB
LLVM
; RUN: opt -jump-threading -S < %s | FileCheck %s
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declare void @side_effect(i32)
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define void @test0(i32 %i, i32 %len) {
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; CHECK-LABEL: @test0(
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entry:
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call void @side_effect(i32 0)
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%i.inc = add nuw i32 %i, 1
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%c0 = icmp ult i32 %i.inc, %len
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br i1 %c0, label %left, label %right
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left:
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; CHECK: entry:
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; CHECK: br i1 %c0, label %left0, label %right
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; CHECK: left0:
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; CHECK: call void @side_effect
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; CHECK-NOT: br i1 %c1
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; CHECK: call void @side_effect
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call void @side_effect(i32 0)
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%c1 = icmp ult i32 %i, %len
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br i1 %c1, label %left0, label %right
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left0:
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call void @side_effect(i32 0)
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ret void
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right:
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%t = phi i32 [ 1, %left ], [ 2, %entry ]
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call void @side_effect(i32 %t)
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ret void
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}
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define void @test1(i32 %i, i32 %len) {
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; CHECK-LABEL: @test1(
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entry:
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call void @side_effect(i32 0)
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%i.inc = add nsw i32 %i, 1
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%c0 = icmp slt i32 %i.inc, %len
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br i1 %c0, label %left, label %right
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left:
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; CHECK: entry:
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; CHECK: br i1 %c0, label %left0, label %right
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; CHECK: left0:
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; CHECK: call void @side_effect
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; CHECK-NOT: br i1 %c1
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; CHECK: call void @side_effect
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call void @side_effect(i32 0)
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%c1 = icmp slt i32 %i, %len
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br i1 %c1, label %left0, label %right
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left0:
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call void @side_effect(i32 0)
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ret void
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right:
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%t = phi i32 [ 1, %left ], [ 2, %entry ]
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call void @side_effect(i32 %t)
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ret void
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}
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define void @test2(i32 %i, i32 %len, i1* %c.ptr) {
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; CHECK-LABEL: @test2(
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; CHECK: entry:
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; CHECK: br i1 %c0, label %cont, label %right
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; CHECK: cont:
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; CHECK: br i1 %c, label %left0, label %right
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; CHECK: left0:
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; CHECK: call void @side_effect(i32 0)
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; CHECK: call void @side_effect(i32 0)
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entry:
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call void @side_effect(i32 0)
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%i.inc = add nsw i32 %i, 1
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%c0 = icmp slt i32 %i.inc, %len
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br i1 %c0, label %cont, label %right
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cont:
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%c = load i1, i1* %c.ptr
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br i1 %c, label %left, label %right
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left:
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call void @side_effect(i32 0)
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%c1 = icmp slt i32 %i, %len
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br i1 %c1, label %left0, label %right
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left0:
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call void @side_effect(i32 0)
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ret void
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right:
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%t = phi i32 [ 1, %left ], [ 2, %entry ], [ 3, %cont ]
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call void @side_effect(i32 %t)
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ret void
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}
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