2003-08-17-FoldSwitch.ll
1.84 KB
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; NOTE: Assertions have been autogenerated by update_test_checks.py
; RUN: opt < %s -simplifycfg -S | FileCheck %s
; Test normal folding
define i32 @test1() {
; CHECK-LABEL: @test1(
; CHECK-NEXT: TheDest:
; CHECK-NEXT: ret i32 1234
;
switch i32 5, label %Default [
i32 0, label %Foo
i32 1, label %Bar
i32 2, label %Baz
i32 5, label %TheDest
]
Default:
ret i32 -1
Foo:
ret i32 -2
Bar:
ret i32 -3
Baz:
ret i32 -4
TheDest:
ret i32 1234
}
; Test folding to default dest
define i32 @test2() {
; CHECK-LABEL: @test2(
; CHECK-NEXT: Default:
; CHECK-NEXT: ret i32 1234
;
switch i32 3, label %Default [
i32 0, label %Foo
i32 1, label %Bar
i32 2, label %Baz
i32 5, label %TheDest
]
Default:
ret i32 1234
Foo:
ret i32 -2
Bar:
ret i32 -5
Baz:
ret i32 -6
TheDest:
ret i32 -8
}
; Test folding all to same dest
define i32 @test3(i1 %C) {
; CHECK-LABEL: @test3(
; CHECK-NEXT: TheDest:
; CHECK-NEXT: ret i32 1234
;
br i1 %C, label %Start, label %TheDest
Start: ; preds = %0
switch i32 3, label %TheDest [
i32 0, label %TheDest
i32 1, label %TheDest
i32 2, label %TheDest
i32 5, label %TheDest
]
TheDest:
ret i32 1234
}
; Test folding switch -> branch
define i32 @test4(i32 %C) {
; CHECK-LABEL: @test4(
; CHECK-NEXT: L1:
; CHECK-NEXT: [[COND:%.*]] = icmp eq i32 %C, 0
; CHECK-NEXT: [[DOT:%.*]] = select i1 [[COND]], i32 1, i32 0
; CHECK-NEXT: ret i32 [[DOT]]
;
switch i32 %C, label %L1 [
i32 0, label %L2
]
L1:
ret i32 0
L2:
ret i32 1
}
; Can fold into a cond branch!
define i32 @test5(i32 %C) {
; CHECK-LABEL: @test5(
; CHECK-NEXT: L1:
; CHECK-NEXT: [[COND:%.*]] = icmp eq i32 %C, 0
; CHECK-NEXT: [[DOT:%.*]] = select i1 [[COND]], i32 1, i32 0
; CHECK-NEXT: ret i32 [[DOT]]
;
switch i32 %C, label %L1 [
i32 0, label %L2
i32 123, label %L1
]
L1:
ret i32 0
L2:
ret i32 1
}