A64: Port LSeqStringGetChar.

A64: Port LSeqStringGetChar.

BUG=
R=rodolph.perfetta@arm.com

Committed: https://code.google.com/p/v8/source/detail?r=19133

[ulan, 2014-02-05 19:03:09]

PTAL

[Rodolph Perfetta (ARM), 2014-02-05 20:07:21]

https://codereview.chromium.org/153993011/diff/60001/src/a64/lithium-codegen-...
File src/a64/lithium-codegen-a64.cc (right):

https://codereview.chromium.org/153993011/diff/60001/src/a64/lithium-codegen-...
src/a64/lithium-codegen-a64.cc:4463: ASSERT(!temp.is(string));
string is declared "AtStart" and temp is declared "TempRegister" so nothing is
stopping the allocator to give them the same register.

https://codereview.chromium.org/153993011/diff/60001/src/a64/lithium-codegen-...
src/a64/lithium-codegen-a64.cc:4464: ASSERT(!temp.is(ToRegister(index)));
ditto.

https://codereview.chromium.org/153993011/diff/60001/src/a64/lithium-codegen-...
src/a64/lithium-codegen-a64.cc:4481: if (FLAG_debug_code) {
because string and index are at start, this debug code could corrupt them.

It's a shame that debug code forces us to put more stringent constraints on the
allocator but we can revisit later if you add a todo.

[ulan, 2014-02-06 08:55:54]

PTAL

https://codereview.chromium.org/153993011/diff/60001/src/a64/lithium-codegen-...
File src/a64/lithium-codegen-a64.cc (right):

https://codereview.chromium.org/153993011/diff/60001/src/a64/lithium-codegen-...
src/a64/lithium-codegen-a64.cc:4481: if (FLAG_debug_code) {
On 2014/02/05 20:07:22, Rodolph Perfetta (ARM) wrote:
> because string and index are at start, this debug code could corrupt them.
> 
> It's a shame that debug code forces us to put more stringent constraints on
the
> allocator but we can revisit later if you add a todo.

Good catch! I removed "AtStart" and added TODO.

[Rodolph Perfetta (ARM), 2014-02-06 09:32:21]

lgtm

[ulan, 2014-02-06 09:43:09]

Committed patchset #3 manually as r19133 (presubmit successful).