Create build structure for X64.

Create build structure for X64.
Possible to attempt to build for X64.
Build will be unsuccessful, since all x64 source files are 
missing and pointers are reinterpreted as integers everywhere.

[Lasse Reichstein, 2009-04-29 11:57:16]

Compiler switches for compiling X64 code.
Only allowed if both wordsize=32 and arch=x64 are supplied, and only on Linux.

[Mads Ager (chromium), 2009-04-29 12:27:24]

LGTM

Could you please add the new files as well?  You can just add empty files at
first that just contain the copyright notice.

http://codereview.chromium.org/99186/diff/1/2
File SConstruct (right):

http://codereview.chromium.org/99186/diff/1/2#newcode155
Line 155: },
Is this comma needed?

http://codereview.chromium.org/99186/diff/1/2#newcode557
Line 557: },
comma needed?

http://codereview.chromium.org/99186/diff/1/3
File src/SConscript (right):

http://codereview.chromium.org/99186/diff/1/3#newcode78
Line 78: # 'x64/regexp-macro-assembler-x64.cc',
Since none of the files exist yet anyway, why is this one commented out?

http://codereview.chromium.org/99186/diff/1/4
File src/codegen.h (right):

http://codereview.chromium.org/99186/diff/1/4#newcode79
Line 79: #ifdef V8_ARCH_ARM
You need to update the other build systems as well in order not to break builds.
 You need to make sure that V8_ARCH_ARM is defined instead of ARM.  You need to
do this in visual studio project, xcode project and the v8.gyp file.

http://codereview.chromium.org/99186/diff/1/6
File src/frames-inl.h (right):

http://codereview.chromium.org/99186/diff/1/6#newcode37
Line 37: #include "ia64/frames-ia64.h"
ia64 / x64 confusion.

http://codereview.chromium.org/99186/diff/1/11
File src/platform-freebsd.cc (right):

http://codereview.chromium.org/99186/diff/1/11#newcode174
Line 174: #ifdef (defined(__arm__) || defined(__thumb__))
Should this just be an #if?

[Lasse Reichstein, 2009-04-29 13:05:41]

Addressed comments.

http://codereview.chromium.org/99186/diff/1/2
File SConstruct (right):

http://codereview.chromium.org/99186/diff/1/2#newcode155
Line 155: },
Not needed. I would prefer to have it everywhere (makes reordering much easier),
but since it's not the style, I should go for consistency instead.

http://codereview.chromium.org/99186/diff/1/3
File src/SConscript (right):

http://codereview.chromium.org/99186/diff/1/3#newcode78
Line 78: # 'x64/regexp-macro-assembler-x64.cc',
Because we can actually do without it. The test for whether to use native or
interpreted regexp is set to use the interpreter (like on ARM).

http://codereview.chromium.org/99186/diff/1/4
File src/codegen.h (right):

http://codereview.chromium.org/99186/diff/1/4#newcode79
Line 79: #ifdef V8_ARCH_ARM
Attempted done. No guarantees on the XCode project file. It's not made for hand
editing.

http://codereview.chromium.org/99186/diff/1/6
File src/frames-inl.h (right):

http://codereview.chromium.org/99186/diff/1/6#newcode37
Line 37: #include "ia64/frames-ia64.h"
Yes, my bad.

http://codereview.chromium.org/99186/diff/1/11
File src/platform-freebsd.cc (right):

http://codereview.chromium.org/99186/diff/1/11#newcode174
Line 174: #ifdef (defined(__arm__) || defined(__thumb__))
Fixed.