forked from OSchip/llvm-project
38 lines
921 B
LLVM
38 lines
921 B
LLVM
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; RUN: opt < %s -reassociate -disable-output
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; It has been detected that dead loops like the one in this test case can be
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; created by -jump-threading (it was detected by a csmith generated program).
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;
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; According to -verify this is valid input (even if it could be discussed if
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; the dead loop really satisfies SSA form).
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;
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; The problem found was that the -reassociate pass ends up in an infinite loop
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; when analysing the 'deadloop1' basic block. See "Bugzilla - Bug 30818".
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define void @deadloop1() {
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br label %endlabel
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deadloop1:
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%1 = xor i32 %2, 7
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%2 = xor i32 %1, 8
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br label %deadloop1
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endlabel:
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ret void
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}
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; Another example showing that dead code could result in infinite loops in
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; reassociate pass. See "Bugzilla - Bug 30818".
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define void @deadloop2() {
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br label %endlabel
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deadloop2:
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%1 = and i32 %2, 7
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%2 = and i32 %3, 8
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%3 = and i32 %1, 6
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br label %deadloop2
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endlabel:
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ret void
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}
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