Faster string equals in generated code.

Faster string equals in generated code.

In my previous change I mixed up "compare" and "equals". This made us
miss the fast length check before comparing strings for equality.

Now we have a separate helper for "equals". It shares some of the
inner loop details with "compare". I'll see if this can be cleaned up
without making it unreadable.

[Mads Ager (chromium), 2011-05-05 07:42:24]

LGTM

http://codereview.chromium.org/6928020/diff/1/src/ia32/code-stubs-ia32.cc
File src/ia32/code-stubs-ia32.cc (right):

http://codereview.chromium.org/6928020/diff/1/src/ia32/code-stubs-ia32.cc#new...
src/ia32/code-stubs-ia32.cc:5655: __ mov_b(scratch2, Operand(left, index,
times_1, 0));
Do you need "times_1, 0" here?

http://codereview.chromium.org/6928020/diff/1/src/x64/code-stubs-x64.cc
File src/x64/code-stubs-x64.cc (right):

http://codereview.chromium.org/6928020/diff/1/src/x64/code-stubs-x64.cc#newco...
src/x64/code-stubs-x64.cc:4541: __ movb(scratch2, Operand(left, index, times_1,
0));
Do you need "times_1, 0" here?

[Vitaly Repeshko, 2011-05-05 11:40:16]

http://codereview.chromium.org/6928020/diff/1/src/ia32/code-stubs-ia32.cc
File src/ia32/code-stubs-ia32.cc (right):

http://codereview.chromium.org/6928020/diff/1/src/ia32/code-stubs-ia32.cc#new...
src/ia32/code-stubs-ia32.cc:5655: __ mov_b(scratch2, Operand(left, index,
times_1, 0));
On 2011/05/05 07:42:24, Mads Ager wrote:
> Do you need "times_1, 0" here?

There's no Operand(reg, reg), only Operand(reg, imm).

http://codereview.chromium.org/6928020/diff/1/src/x64/code-stubs-x64.cc
File src/x64/code-stubs-x64.cc (right):

http://codereview.chromium.org/6928020/diff/1/src/x64/code-stubs-x64.cc#newco...
src/x64/code-stubs-x64.cc:4541: __ movb(scratch2, Operand(left, index, times_1,
0));
On 2011/05/05 07:42:24, Mads Ager wrote:
> Do you need "times_1, 0" here?

Same here.