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; RUN: opt < %s -simplifycfg -S | FileCheck %s
define void @test1(i1 %C, i1* %BP) {
; CHECK-LABEL: @test1(
; CHECK: entry:
; CHECK-NEXT: ret void
entry:
br i1 %C, label %T, label %F
T:
store i1 %C, i1* %BP
unreachable
F:
ret void
}
define void @test2() {
; CHECK-LABEL: @test2(
; CHECK: entry:
; CHECK-NEXT: call void @test2()
; CHECK-NEXT: ret void
entry:
invoke void @test2( )
to label %N unwind label %U
U:
unreachable
N:
ret void
}
define i32 @test3(i32 %v) {
; CHECK-LABEL: @test3(
; CHECK: entry:
; CHECK-NEXT: [[CMP:%[A-Za-z0-9]+]] = icmp eq i32 %v, 2
; CHECK-NEXT: select i1 [[CMP]], i32 2, i32 1
; CHECK-NEXT: ret
entry:
switch i32 %v, label %default [
i32 1, label %U
i32 2, label %T
]
default:
ret i32 1
U:
unreachable
T:
ret i32 2
}
;; We can either convert the following control-flow to a select or remove the
;; unreachable control flow because of the undef store of null. Make sure we do
;; the latter.
define void @test5(i1 %cond, i8* %ptr) {
; CHECK-LABEL: test5
; CHECK: entry:
; CHECK-NOT: select
; CHECK: store i8 2, i8* %ptr
; CHECK: ret
entry:
br i1 %cond, label %bb1, label %bb3
bb3:
br label %bb2
bb1:
br label %bb2
bb2:
%ptr.2 = phi i8* [ %ptr, %bb3 ], [ null, %bb1 ]
store i8 2, i8* %ptr.2, align 8
ret void
}
; CHECK-LABEL: test6
; CHECK: entry:
; CHECK-NOT: select
; CHECK: store i8 2, i8* %ptr
; CHECK: ret
define void @test6(i1 %cond, i8* %ptr) {
entry:
br i1 %cond, label %bb1, label %bb2
bb1:
br label %bb2
bb2:
%ptr.2 = phi i8* [ %ptr, %entry ], [ null, %bb1 ]
store i8 2, i8* %ptr.2, align 8
ret void
}
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