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50e8682f28
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@6965 91177308-0d34-0410-b5e6-96231b3b80d8
24 lines
817 B
LLVM
24 lines
817 B
LLVM
; edgefailure - This function illustrates how SCCP is not doing it's job. This
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; function should be optimized almost completely away: the loop should be
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; analyzed to detect that the body executes exactly once, and thus the branch
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; can be eliminated and code becomes trivially dead. This is distilled from a
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; real benchmark (mst from Olden benchmark, MakeGraph function). When SCCP is
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; fixed, this should be eliminated by a single SCCP application.
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;
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; RUN: as < %s | opt -sccp | dis | not grep loop
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int* %test() {
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bb1:
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%A = malloc int
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br label %bb2
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bb2:
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%i = phi int [ %i2, %bb2 ], [ 0, %bb1 ] ;; Always 0
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%i2 = add int %i, 1 ;; Always 1
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store int %i, int *%A
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%loop = setle int %i2, 0 ;; Always false
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br bool %loop, label %bb2, label %bb3
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bb3:
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ret int * %A
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}
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