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| ; RUN: opt -jump-threading -S < %s | FileCheck %s
declare void @side_effect(i32)
define void @test0(i32 %i, i32 %len) {
; CHECK-LABEL: @test0(
entry:
call void @side_effect(i32 0)
%i.inc = add nuw i32 %i, 1
%c0 = icmp ult i32 %i.inc, %len
br i1 %c0, label %left, label %right
left:
; CHECK: entry:
; CHECK: br i1 %c0, label %left0, label %right
; CHECK: left0:
; CHECK: call void @side_effect
; CHECK-NOT: br i1 %c1
; CHECK: call void @side_effect
call void @side_effect(i32 0)
%c1 = icmp ult i32 %i, %len
br i1 %c1, label %left0, label %right
left0:
call void @side_effect(i32 0)
ret void
right:
%t = phi i32 [ 1, %left ], [ 2, %entry ]
call void @side_effect(i32 %t)
ret void
}
define void @test1(i32 %i, i32 %len) {
; CHECK-LABEL: @test1(
entry:
call void @side_effect(i32 0)
%i.inc = add nsw i32 %i, 1
%c0 = icmp slt i32 %i.inc, %len
br i1 %c0, label %left, label %right
left:
; CHECK: entry:
; CHECK: br i1 %c0, label %left0, label %right
; CHECK: left0:
; CHECK: call void @side_effect
; CHECK-NOT: br i1 %c1
; CHECK: call void @side_effect
call void @side_effect(i32 0)
%c1 = icmp slt i32 %i, %len
br i1 %c1, label %left0, label %right
left0:
call void @side_effect(i32 0)
ret void
right:
%t = phi i32 [ 1, %left ], [ 2, %entry ]
call void @side_effect(i32 %t)
ret void
}
define void @test2(i32 %i, i32 %len, i1* %c.ptr) {
; CHECK-LABEL: @test2(
; CHECK: entry:
; CHECK: br i1 %c0, label %cont, label %right
; CHECK: cont:
; CHECK: br i1 %c, label %left0, label %right
; CHECK: left0:
; CHECK: call void @side_effect(i32 0)
; CHECK: call void @side_effect(i32 0)
entry:
call void @side_effect(i32 0)
%i.inc = add nsw i32 %i, 1
%c0 = icmp slt i32 %i.inc, %len
br i1 %c0, label %cont, label %right
cont:
%c = load i1, i1* %c.ptr
br i1 %c, label %left, label %right
left:
call void @side_effect(i32 0)
%c1 = icmp slt i32 %i, %len
br i1 %c1, label %left0, label %right
left0:
call void @side_effect(i32 0)
ret void
right:
%t = phi i32 [ 1, %left ], [ 2, %entry ], [ 3, %cont ]
call void @side_effect(i32 %t)
ret void
}
; A s<= B implies A s> B is false.
; CHECK-LABEL: @test3(
; CHECK: entry:
; CHECK: br i1 %cmp, label %if.end, label %if.end3
; CHECK-NOT: br i1 %cmp1, label %if.then2, label %if.end
; CHECK-NOT: call void @side_effect(i32 0)
; CHECK: br label %if.end3
; CHECK: ret void
define void @test3(i32 %a, i32 %b) {
entry:
%cmp = icmp sle i32 %a, %b
br i1 %cmp, label %if.then, label %if.end3
if.then:
%cmp1 = icmp sgt i32 %a, %b
br i1 %cmp1, label %if.then2, label %if.end
if.then2:
call void @side_effect(i32 0)
br label %if.end
if.end:
br label %if.end3
if.end3:
ret void
}
declare void @is(i1)
; If A >=s B is false then A <=s B is implied true.
; CHECK-LABEL: @test_sge_sle
; CHECK: call void @is(i1 true)
; CHECK-NOT: call void @is(i1 false)
define void @test_sge_sle(i32 %a, i32 %b) {
%cmp1 = icmp sge i32 %a, %b
br i1 %cmp1, label %untaken, label %taken
taken:
%cmp2 = icmp sle i32 %a, %b
br i1 %cmp2, label %istrue, label %isfalse
istrue:
call void @is(i1 true)
ret void
isfalse:
call void @is(i1 false)
ret void
untaken:
ret void
}
; If A <=s B is false then A <=s B is implied false.
; CHECK-LABEL: @test_sle_sle
; CHECK-NOT: call void @is(i1 true)
; CHECK: call void @is(i1 false)
define void @test_sle_sle(i32 %a, i32 %b) {
%cmp1 = icmp sle i32 %a, %b
br i1 %cmp1, label %untaken, label %taken
taken:
%cmp2 = icmp sle i32 %a, %b
br i1 %cmp2, label %istrue, label %isfalse
istrue:
call void @is(i1 true)
ret void
isfalse:
call void @is(i1 false)
ret void
untaken:
ret void
}
|