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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94317 91177308-0d34-0410-b5e6-96231b3b80d8
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@ -635,6 +635,35 @@ This sort of thing occurs a lot due to globalopt.
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===-------------------------------------------------------------------------===
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===-------------------------------------------------------------------------===
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We compile:
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define i32 @bar(i32 %x) nounwind readnone ssp {
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entry:
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%0 = icmp eq i32 %x, 0 ; <i1> [#uses=1]
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%neg = select i1 %0, i32 -1, i32 0 ; <i32> [#uses=1]
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ret i32 %neg
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}
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to:
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_bar:
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cmplwi cr0, r3, 0
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li r3, -1
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beq cr0, LBB1_2
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; BB#1: ; %entry
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li r3, 0
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LBB1_2: ; %entry
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blr
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it would be much better to produce:
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_bar:
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addic r3,r3,-1
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subfe r3,r3,r3
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blr
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===-------------------------------------------------------------------------===
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We currently compile 32-bit bswap:
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We currently compile 32-bit bswap:
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declare i32 @llvm.bswap.i32(i32 %A)
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declare i32 @llvm.bswap.i32(i32 %A)
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