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| ; RUN: opt %s -S -simplifycfg | FileCheck %s
; cmp1 implies cmp2 is false
; CHECK-LABEL: @test1
; CHECK-NOT: call void @is(i1 true)
; CHECK: call void @is(i1 false)
define void @test1(i32 %a) {
%cmp1 = icmp eq i32 %a, 0
br i1 %cmp1, label %taken, label %untaken
taken:
%cmp2 = icmp eq i32 %a, 1
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
}
; cmp1 implies cmp2 is false
; CHECK-LABEL: @test2
; CHECK-NOT: call void @is(i1 true)
; CHECK: call void @is(i1 false)
define void @test2(i32 %a) {
%cmp1 = icmp ugt i32 %a, 5
br i1 %cmp1, label %untaken, label %taken
taken:
%cmp2 = icmp ugt i32 %a, 6
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
}
; cmp1 implies cmp2 is false
; CHECK-LABEL: @test3
; CHECK-NOT: call void @is(i1 true)
; CHECK: call void @is(i1 false)
define void @test3(i32 %a) {
%cmp1 = icmp ugt i32 %a, 1
br i1 %cmp1, label %taken, label %untaken
taken:
%cmp2 = icmp eq i32 %a, 0
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
}
; cmp1 implies cmp2 is true
; CHECK-LABEL: @test4
; CHECK: call void @is(i1 true)
; CHECK-NOT: call void @is(i1 false)
define void @test4(i32 %a) {
%cmp1 = icmp sgt i32 %a, 1
br i1 %cmp1, label %taken, label %untaken
taken:
%cmp2 = icmp ugt i32 %a, 0
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
}
; cmp1 implies cmp2 is true
; CHECK-LABEL: @test5
; CHECK: call void @is(i1 true)
; CHECK-NOT: call void @is(i1 false)
define void @test5(i32 %a) {
%cmp1 = icmp sgt i32 %a, 5
br i1 %cmp1, label %taken, label %untaken
taken:
%cmp2 = icmp sgt i32 %a, -1
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
}
declare void @is(i1)
|