80 lines
2.2 KiB
LLVM
80 lines
2.2 KiB
LLVM
; RUN: opt < %s -simplifycfg -S | \
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; RUN: not grep {call void @DEAD}
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; Test that we can thread a simple known condition through switch statements.
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declare void @foo1()
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declare void @foo2()
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declare void @DEAD()
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define void @test1(i32 %V) {
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switch i32 %V, label %A [
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i32 4, label %T
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i32 17, label %Done
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i32 1234, label %A
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]
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;; V == 4 if we get here.
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T: ; preds = %0
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call void @foo1( )
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;; This switch is always statically determined.
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switch i32 %V, label %A2 [
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i32 4, label %B
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i32 17, label %C
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i32 42, label %C
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]
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A2: ; preds = %T
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call void @DEAD( )
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call void @DEAD( )
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;; always true
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%cond2 = icmp eq i32 %V, 4 ; <i1> [#uses=1]
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br i1 %cond2, label %Done, label %C
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A: ; preds = %0, %0
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call void @foo1( )
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;; always true
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%cond = icmp ne i32 %V, 4 ; <i1> [#uses=1]
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br i1 %cond, label %Done, label %C
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Done: ; preds = %B, %A, %A2, %0
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ret void
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B: ; preds = %T
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call void @foo2( )
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;; always true
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%cond3 = icmp eq i32 %V, 4 ; <i1> [#uses=1]
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br i1 %cond3, label %Done, label %C
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C: ; preds = %B, %A, %A2, %T, %T
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call void @DEAD( )
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ret void
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}
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define void @test2(i32 %V) {
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switch i32 %V, label %A [
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i32 4, label %T
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i32 17, label %D
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i32 1234, label %E
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]
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;; V != 4, 17, 1234 here.
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A: ; preds = %0
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call void @foo1( )
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;; This switch is always statically determined.
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switch i32 %V, label %E [
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i32 4, label %C
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i32 17, label %C
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i32 42, label %D
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]
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;; unreacahble.
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C: ; preds = %A, %A
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call void @DEAD( )
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ret void
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T: ; preds = %0
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call void @foo1( )
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call void @foo1( )
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ret void
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D: ; preds = %A, %0
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call void @foo1( )
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ret void
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E: ; preds = %A, %0
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ret void
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}
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