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; RUN: llvm-as < %s | opt -simplifycfg | llvm-dis | \
; RUN: not grep switch
; Test normal folding
define i32 @test1() {
switch i32 5, label %Default [
i32 0, label %Foo
i32 1, label %Bar
i32 2, label %Baz
i32 5, label %TheDest
]
Default: ; preds = %0
ret i32 -1
Foo: ; preds = %0
ret i32 -2
Bar: ; preds = %0
ret i32 -3
Baz: ; preds = %0
ret i32 -4
TheDest: ; preds = %0
ret i32 1234
}
; Test folding to default dest
define i32 @test2() {
switch i32 3, label %Default [
i32 0, label %Foo
i32 1, label %Bar
i32 2, label %Baz
i32 5, label %TheDest
]
Default: ; preds = %0
ret i32 1234
Foo: ; preds = %0
ret i32 -2
Bar: ; preds = %0
ret i32 -5
Baz: ; preds = %0
ret i32 -6
TheDest: ; preds = %0
ret i32 -8
}
; Test folding all to same dest
define i32 @test3(i1 %C) {
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: ; preds = %Start, %Start, %Start, %Start, %Start, %0
ret i32 1234
}
; Test folding switch -> branch
define i32 @test4(i32 %C) {
switch i32 %C, label %L1 [
i32 0, label %L2
]
L1: ; preds = %0
ret i32 0
L2: ; preds = %0
ret i32 1
}
; Can fold into a cond branch!
define i32 @test5(i32 %C) {
switch i32 %C, label %L1 [
i32 0, label %L2
i32 123, label %L1
]
L1: ; preds = %0, %0
ret i32 0
L2: ; preds = %0
ret i32 1
}
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