parent
9b41823177
commit
bb10e90487
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@ -1919,5 +1919,21 @@ something like the following, which eliminates a branch:
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ret
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ret
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.LBB0_2:
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.LBB0_2:
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jmp foo # TAILCALL
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jmp foo # TAILCALL
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//===---------------------------------------------------------------------===//
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Given a branch where the two target blocks are identical ("ret i32 %b" in
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both), simplifycfg will simplify them away. But not so for a switch statement:
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define i32 @f(i32 %a, i32 %b) nounwind readnone {
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entry:
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switch i32 %a, label %bb3 [
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i32 4, label %bb
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i32 6, label %bb
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]
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bb: ; preds = %entry, %entry
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ret i32 %b
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bb3: ; preds = %entry
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ret i32 %b
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}
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//===---------------------------------------------------------------------===//
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//===---------------------------------------------------------------------===//
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