Faster slow asserts.

Faster slow asserts.
Committed: http://code.google.com/p/v8/source/detail?r=9607

[Vyacheslav Egorov (Chromium), 2011-10-13 11:53:52]

LGTM

[Sven Panne, 2011-10-13 13:07:00]

http://codereview.chromium.org/8267004/diff/1/src/checks.h
File src/checks.h (right):

http://codereview.chromium.org/8267004/diff/1/src/checks.h#newcode273
src/checks.h:273: #define SLOW_ASSERT(condition) if (FLAG_enable_slow_asserts)
CHECK(condition)
Although it's a bit late for a comment: Using the ugly, but common "do { if ...
} while(0)" idiom here would be safer...

[Kevin Millikin (Chromium), 2011-10-13 13:21:19]

http://codereview.chromium.org/8267004/diff/1/src/checks.h
File src/checks.h (right):

http://codereview.chromium.org/8267004/diff/1/src/checks.h#newcode273
src/checks.h:273: #define SLOW_ASSERT(condition) if (FLAG_enable_slow_asserts)
CHECK(condition)
On 2011/10/13 13:07:00, Sven wrote:
> Although it's a bit late for a comment: Using the ugly, but common "do { if
...
> } while(0)" idiom here would be safer...

Yes, we need that, or else the ugly

if (FLAG_enable_slow_asserts) CHECK(condition) else (void)0

as used in the CHECK_OK macro in parser.h.

[Sven Panne, 2011-10-13 14:09:25]

On 2011/10/13 13:21:19, Kevin Millikin wrote:
> http://codereview.chromium.org/8267004/diff/1/src/checks.h
> File src/checks.h (right):
> 
> http://codereview.chromium.org/8267004/diff/1/src/checks.h#newcode273
> src/checks.h:273: #define SLOW_ASSERT(condition) if (FLAG_enable_slow_asserts)
> CHECK(condition)
> On 2011/10/13 13:07:00, Sven wrote:
> > Although it's a bit late for a comment: Using the ugly, but common "do { if
> ...
> > } while(0)" idiom here would be safer...
> 
> Yes, we need that, or else the ugly
> 
> if (FLAG_enable_slow_asserts) CHECK(condition) else (void)0
> 
> as used in the CHECK_OK macro in parser.h.

I've just seen CHECK_OK for the first time... o_O This even beats our usual 2nd
order macros in terms of "readability". +1 for the greatest CPP abuse in v8! :-)