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Chandler fixed this.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147247 91177308-0d34-0410-b5e6-96231b3b80d8
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@ -2060,35 +2060,3 @@ Instead we could generate:
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The trick is to match "fetch_and_add(X, -C) == C".
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//===---------------------------------------------------------------------===//
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unsigned log2(unsigned x) {
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return x > 1 ? 32-__builtin_clz(x-1) : 0;
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}
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generates (x86_64):
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xorl %eax, %eax
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cmpl $2, %edi
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jb LBB0_2
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## BB#1:
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decl %edi
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movl $63, %ecx
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bsrl %edi, %eax
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cmovel %ecx, %eax
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xorl $-32, %eax
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addl $33, %eax
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LBB0_2:
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ret
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The cmov and the early test are redundant:
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xorl %eax, %eax
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cmpl $2, %edi
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jb LBB0_2
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## BB#1:
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decl %edi
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bsrl %edi, %eax
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xorl $-32, %eax
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addl $33, %eax
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LBB0_2:
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ret
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//===---------------------------------------------------------------------===//
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