On Nov 20, 2010, at 3:57 PM, John McCall wrote:
>>
>> I agree that it would make it easier to read/know. On the other hand, /* */
>> comments have a nice vectorized comment skipper and // don't (and can't
>> reasonably). It probably isn't measurable, but this means that // comments
>> are slower to lex than /* comments :-)
>
> If you're really concerned about this, you *can* put BCPL comments inside C
> comments. I, too, frequently find myself confused when looking at these
> headers because of the lengthy comments-than-don't-look-like-comments.
Yeah, but that also defeats the vectorized comment skipper:
// Skip over all non-interesting characters until we find end of buffer or a
// (probably ending) '/' character.
if (CurPtr + 24 < BufferEnd) {
// While not aligned to a 16-byte boundary.
while (C != '/' && ((intptr_t)CurPtr & 0x0F) != 0)
C = *CurPtr++;
if (C == '/') goto FoundSlash;
#ifdef __SSE2__
__m128i Slashes = _mm_set_epi8('/', '/', '/', '/', '/', '/', '/', '/',
'/', '/', '/', '/', '/', '/', '/', '/');
while (CurPtr+16 <= BufferEnd &&
_mm_movemask_epi8(_mm_cmpeq_epi8(*(__m128i*)CurPtr, Slashes)) == 0)
CurPtr += 16;
#elif __ALTIVEC__
...
-Chris
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