Increase coverage of global loads in optimized code

Increase coverage of global loads in optimized code

In the cases where a global property cell cannot be used in the optimized code
use standard load ic to get the property instead of bailing out.

This is re-committing r7212 and r7215 which where reverted in r7239 with the addition of recoring the source position in the hydrogen code for the LoadGlobalCell instruction. To record that position an optional position field has been added to the variable proxy AST node.
Committed: http://code.google.com/p/v8/source/detail?r=7474

[Søren Thygesen Gjesse, 2011-04-01 10:56:05]

The original patch is in patch set 1 and 2 and patch set 3 is the changes to
record the position. Patch set 4 is just a rebase.

[fschneider, 2011-04-01 11:38:57]

LGTM.

http://codereview.chromium.org/6758007/diff/11008/src/arm/lithium-arm.cc
File src/arm/lithium-arm.cc (right):

http://codereview.chromium.org/6758007/diff/11008/src/arm/lithium-arm.cc#newc...
src/arm/lithium-arm.cc:1727: LLoadGlobalCell* result = new LLoadGlobalCell();
Should be enough to write:

new LLoadGlobalCell;

http://codereview.chromium.org/6758007/diff/11008/src/arm/lithium-codegen-arm.cc
File src/arm/lithium-codegen-arm.cc (right):

http://codereview.chromium.org/6758007/diff/11008/src/arm/lithium-codegen-arm...
src/arm/lithium-codegen-arm.cc:2183: RelocInfo::Mode mode = instr->for_typeof()
? RelocInfo::CODE_TARGET :
For consistency maybe align like

? RelocInfo::CODE_TARGET
: RelocInfo::CODE_TARGET_CONTEXT;

http://codereview.chromium.org/6758007/diff/11008/src/ast.cc
File src/ast.cc (right):

http://codereview.chromium.org/6758007/diff/11008/src/ast.cc#newcode96
src/ast.cc:96: // names must be canonicalized for fast equality checks
-->Names must be canonicalized for fast equality checks.

[Søren Thygesen Gjesse, 2011-04-01 11:47:31]

http://codereview.chromium.org/6758007/diff/11008/src/arm/lithium-arm.cc
File src/arm/lithium-arm.cc (right):

http://codereview.chromium.org/6758007/diff/11008/src/arm/lithium-arm.cc#newc...
src/arm/lithium-arm.cc:1727: LLoadGlobalCell* result = new LLoadGlobalCell();
On 2011/04/01 11:38:57, fschneider wrote:
> Should be enough to write:
> 
> new LLoadGlobalCell; 

Done.

http://codereview.chromium.org/6758007/diff/11008/src/arm/lithium-codegen-arm.cc
File src/arm/lithium-codegen-arm.cc (right):

http://codereview.chromium.org/6758007/diff/11008/src/arm/lithium-codegen-arm...
src/arm/lithium-codegen-arm.cc:2183: RelocInfo::Mode mode = instr->for_typeof()
? RelocInfo::CODE_TARGET :
On 2011/04/01 11:38:57, fschneider wrote:
> For consistency maybe align like
> 
> ? RelocInfo::CODE_TARGET
> : RelocInfo::CODE_TARGET_CONTEXT;

Done.

http://codereview.chromium.org/6758007/diff/11008/src/ast.cc
File src/ast.cc (right):

http://codereview.chromium.org/6758007/diff/11008/src/ast.cc#newcode96
src/ast.cc:96: // names must be canonicalized for fast equality checks
On 2011/04/01 11:38:57, fschneider wrote:
> -->Names must be canonicalized for fast equality checks.

Done.