Refactor x64 named loads to agree with ia32 implementation. Remove dead code...

Refactor x64 named loads to agree with ia32 implementation.  Remove dead code and flag is_global from x64 keyed loads.

Committed: http://code.google.com/p/v8/source/detail?r=4728

[Vyacheslav Egorov (Chromium), 2010-05-26 07:53:04]

LGTM with comments addressed.

(unfortunately similarities in code are very confusing because we consume
arguments in a slightly different way in x64 and ia32).

http://codereview.chromium.org/2121022/diff/1/2
File src/ia32/codegen-ia32.cc (right):

http://codereview.chromium.org/2121022/diff/1/2#newcode8646
src/ia32/codegen-ia32.cc:8646: key.reg(),
indentation is off

http://codereview.chromium.org/2121022/diff/1/3
File src/x64/codegen-x64.cc (left):

http://codereview.chromium.org/2121022/diff/1/3#oldcode7428
src/x64/codegen-x64.cc:7428: }
I see no reason to duplicate this code inside cases. 
UnloadReference() seems to handle SLOT case correctly.

http://codereview.chromium.org/2121022/diff/1/3
File src/x64/codegen-x64.cc (right):

http://codereview.chromium.org/2121022/diff/1/3#newcode7200
src/x64/codegen-x64.cc:7200: result = frame()->CallLoadIC(mode);
CallLoadIC() behaves differently on ia32 and x64. Comment that it does not drop
receiver?

http://codereview.chromium.org/2121022/diff/1/3#newcode7257
src/x64/codegen-x64.cc:7257: ASSERT(frame()->height() == original_height);
Implementation disagrees with comment in header file.
Comment declares that receiver is consumed.

http://codereview.chromium.org/2121022/diff/1/3#newcode7332
src/x64/codegen-x64.cc:7332: __ CompareRoot(elements.reg(),
Heap::kTheHoleValueRootIndex);
move result = elements above this line to agree with ia32? elements is no longer
used as elements here.

http://codereview.chromium.org/2121022/diff/1/3#newcode7402
src/x64/codegen-x64.cc:7402: // if (persist_after_get_) cgen_->frame()->Dup();
commented code

http://codereview.chromium.org/2121022/diff/1/3#newcode7414
src/x64/codegen-x64.cc:7414: //        cgen_->frame()->PushElementAt(1);
commented code

[William Hesse, 2010-05-26 11:38:25]

http://codereview.chromium.org/2121022/diff/1/3
File src/x64/codegen-x64.cc (left):

http://codereview.chromium.org/2121022/diff/1/3#oldcode7428
src/x64/codegen-x64.cc:7428: }
On 2010/05/26 07:53:04, Vyacheslav Egorov wrote:
> I see no reason to duplicate this code inside cases. 
> UnloadReference() seems to handle SLOT case correctly.

It is a step toward changing the Load and KeyedLoad ICs.  To change one without
changing the other, requires us to change UnloadReference to set_unloaded in
separate changes in the two places.

http://codereview.chromium.org/2121022/diff/1/3
File src/x64/codegen-x64.cc (right):

http://codereview.chromium.org/2121022/diff/1/3#newcode7200
src/x64/codegen-x64.cc:7200: result = frame()->CallLoadIC(mode);
On 2010/05/26 07:53:04, Vyacheslav Egorov wrote:
> CallLoadIC() behaves differently on ia32 and x64. Comment that it does not
drop
> receiver? 

We will be changing this in the subsequent change list.  But a temporary comment
is fine.

http://codereview.chromium.org/2121022/diff/1/3#newcode7257
src/x64/codegen-x64.cc:7257: ASSERT(frame()->height() == original_height);
On 2010/05/26 07:53:04, Vyacheslav Egorov wrote:
> Implementation disagrees with comment in header file.
> Comment declares that receiver is consumed. 

Done.

http://codereview.chromium.org/2121022/diff/1/3#newcode7332
src/x64/codegen-x64.cc:7332: __ CompareRoot(elements.reg(),
Heap::kTheHoleValueRootIndex);
On 2010/05/26 07:53:04, Vyacheslav Egorov wrote:
> move result = elements above this line to agree with ia32? elements is no
longer
> used as elements here.

Done.

http://codereview.chromium.org/2121022/diff/1/3#newcode7402
src/x64/codegen-x64.cc:7402: // if (persist_after_get_) cgen_->frame()->Dup();
On 2010/05/26 07:53:04, Vyacheslav Egorov wrote:
> commented code

Done.

http://codereview.chromium.org/2121022/diff/1/3#newcode7414
src/x64/codegen-x64.cc:7414: //        cgen_->frame()->PushElementAt(1);
On 2010/05/26 07:53:04, Vyacheslav Egorov wrote:
> commented code

Done.