Backed out the micro-optimization in 1.4. It was to help gcc-2.6.3
on i486's (and probably i386's), but it has had very little effect since gcc-2.7 or gcc-2.95. With gcc-3.3, it gave a small pessimization for at least i386's, athlon-xp's and pentium4's, a small optimization (I think) for pentium1's, and made no difference for i386's. (movzbl is best for all the later processors, and the micro-optimization was to stop it being used on i486's.)
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2020-12-20 02:59:44 +00:00
svn path=/head/; revision=118017
@ -49,12 +49,7 @@ scanc(size, cp, table, mask0)
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mask = mask0;
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for (end = &cp[size]; cp < end; ++cp) {
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/*
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* gcc-2.6.3 generates poor (un)sign extension code on i386's.
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* The cast to volatile should have no effect, but in fact it
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* improves the code on i386's.
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*/
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if (table[*(volatile const u_char *)cp] & mask)
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if (table[*cp] & mask)
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break;
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}
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return (end - cp);
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