http://codereview.chromium.org/7744052/diff/1/src/ia32/code-stubs-ia32.cc File src/ia32/code-stubs-ia32.cc (right):
http://codereview.chromium.org/7744052/diff/1/src/ia32/code-stubs-ia32.cc#newcode5707 src/ia32/code-stubs-ia32.cc:5707: __ SmiTag(edx); // Make edx a smi again. On 2011/08/29 14:51:27, antonm wrote:
On 2011/08/29 12:55:56, Yang wrote: > On 2011/08/26 16:10:55, antonm wrote: > > do you want to fallback here from make_two_character_string? > > Yes.
Brevity is .... :) I meant you know for sure you won't need a slice
for two
char string, so you're doing redundant work.
Oups. I actually managed to overlook this simple fact. Thanks. http://codereview.chromium.org/7744052/diff/1/src/ia32/code-stubs-ia32.cc#newcode5728 src/ia32/code-stubs-ia32.cc:5728: const uint32_t kSlicedNotConsMask = kSlicedStringTag & ~kConsStringTag; On 2011/08/29 14:51:27, antonm wrote:
On 2011/08/26 16:10:55, antonm wrote: > lift those constants into objects.h?
any response?
I did move these two lines into objects.h Maybe you were looking in the wrong diff. http://codereview.chromium.org/7744052/diff/1/src/ia32/code-stubs-ia32.cc#newcode5747 src/ia32/code-stubs-ia32.cc:5747: __ mov(edi, eax); On 2011/08/29 14:51:27, antonm wrote:
On 2011/08/29 12:55:56, Yang wrote: > On 2011/08/26 16:10:55, antonm wrote: > > maybe keep the parent string in eax and save this move? > > eax has to be used as destination when allocation the new sliced
string and as
> return value.
I am not sure, apparently you can allocate into any register you like,
at least
w/ some minimal amount of work (at least AllocateInNewSpace behaves
this way) Yes but the issue is that the return value of this code stub is fixed to be eax. Now I could of course load the original string into edi to begin with, but then I would have to move edi into eax in case the substring is the same as the original string. So the issue is that the return value has to be eax, the original string has to be loaded into eax as well since we need to be able to return the original string immediately if necessary. http://codereview.chromium.org/7744052/ -- v8-dev mailing list [email protected] http://groups.google.com/group/v8-dev
