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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@109448 91177308-0d34-0410-b5e6-96231b3b80d8
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@ -636,3 +636,24 @@ A custom Thumb version would also be a slight improvement over the generic
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version.
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//===---------------------------------------------------------------------===//
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Consider the following simple C code:
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void foo(unsigned char *a, unsigned char *b, int *c) {
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if ((*a | *b) == 0) *c = 0;
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}
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currently llvm-gcc generates something like this (nice branchless code I'd say):
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ldrb r0, [r0]
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ldrb r1, [r1]
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orr r0, r1, r0
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tst r0, #255
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moveq r0, #0
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streq r0, [r2]
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bx lr
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Note that both "tst" and "moveq" are redundant.
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//===---------------------------------------------------------------------===//
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