Avoid a smi check when comparing an unknown to a constant smi for equality on...

Avoid a smi check when comparing an unknown to a constant smi for equality on ia32 and x64 platforms.

Committed: http://code.google.com/p/v8/source/detail?r=5077

[William Hesse, 2010-07-13 14:19:58]

Will fix lint error.

[Mads Ager (chromium), 2010-07-13 17:21:20]

LGTM

Return statement comments below apply to x64 as well.

http://codereview.chromium.org/2897013/diff/1/2
File src/ia32/codegen-ia32.cc (right):

http://codereview.chromium.org/2897013/diff/1/2#newcode2806
src/ia32/codegen-ia32.cc:2806: return;
I think I would prefer an else instead of the return here.

http://codereview.chromium.org/2897013/diff/1/2#newcode2840
src/ia32/codegen-ia32.cc:2840: return;
And here as well.

http://codereview.chromium.org/2897013/diff/1/2#newcode2878
src/ia32/codegen-ia32.cc:2878: not_number.Branch(not_equal, left_side);
Indentation is off from here.

http://codereview.chromium.org/2897013/diff/1/3
File src/ia32/codegen-ia32.h (right):

http://codereview.chromium.org/2897013/diff/1/3#newcode563
src/ia32/codegen-ia32.h:563: // If at least one of the sides is a constant smi,
generate optimized code.
Could you add a blank line before the comment.

http://codereview.chromium.org/2897013/diff/1/5
File src/x64/codegen-x64.h (right):

http://codereview.chromium.org/2897013/diff/1/5#newcode524
src/x64/codegen-x64.h:524: // If at least one of the sides is a constant smi,
generate optimized code.
Could you add a blank line before the comment?

[William Hesse, 2010-07-15 08:51:04]

Comments all addressed.  Code modified to make the smi case fall through at the
end, in case cc != equal, to avoid a performance regression.