Clean up Makefile, enable MIPS cross-compilation

Clean up Makefile, enable MIPS cross-compilation

Committed: https://code.google.com/p/v8/source/detail?r=11486

[palfia, 2012-05-02 18:39:21]

It works fine for mips target with CodeSourcery toolchain, but it failed to
build V8 with ubuntu's default gcc (4.4.3-4ubuntu5.1) for mips simulator,
because gcc returns misleading return value (please look at my in-line
comments).

https://chromiumcodereview.appspot.com/10268010/diff/1/build/common.gypi
File build/common.gypi (right):

https://chromiumcodereview.appspot.com/10268010/diff/1/build/common.gypi#newc...
build/common.gypi:177: 'mipscompiler': '<!((echo | $(echo ${CXX:-$(which g++)})
-EL -E - > /dev/null 2>&1) && echo -n "yes" || echo -n "no")',
This command:
echo | $(echo ${CXX:-$(which g++)}) -EL -E -
always returns 0 on my system, even if gcc doesn't support mips target.
My suggestion is to use -march=mips32r3 instead of -EL .
So the actual command would be:
(echo | $(echo ${CXX:-$(which g++)}) -march=mips32r2 -E - > /dev/null 2>&1) &&
echo -n "yes" || echo -n "no")

[palfia, 2012-05-02 18:54:50]

https://chromiumcodereview.appspot.com/10268010/diff/1/build/common.gypi
File build/common.gypi (right):

https://chromiumcodereview.appspot.com/10268010/diff/1/build/common.gypi#newc...
build/common.gypi:177: 'mipscompiler': '<!((echo | $(echo ${CXX:-$(which g++)})
-EL -E - > /dev/null 2>&1) && echo -n "yes" || echo -n "no")',
On 2012/05/02 18:39:21, palfia wrote:
> This command:
> echo | $(echo ${CXX:-$(which g++)}) -EL -E -
> always returns 0 on my system, even if gcc doesn't support mips target.
> My suggestion is to use -march=mips32r3 instead of -EL .
> So the actual command would be:
> (echo | $(echo ${CXX:-$(which g++)}) -march=mips32r2 -E - > /dev/null 2>&1) &&
> echo -n "yes" || echo -n "no")

Small typo: "-march=mips32r3" should be "-march=mips32r2"

[Jakob Kummerow, 2012-05-03 07:37:02]

OK, changed the MIPS compiler detection. Checking the "Target:" line of "g++
-v"'s output should be a generally better approach than testing acceptance of
flags.

Sven: Please take a look.

[Sven Panne, 2012-05-03 07:46:41]

LGTM with nits.

https://chromiumcodereview.appspot.com/10268010/diff/5001/build/common.gypi
File build/common.gypi (right):

https://chromiumcodereview.appspot.com/10268010/diff/5001/build/common.gypi#n...
build/common.gypi:177: 'mipscompiler': '<!($(echo ${CXX:-$(which g++)}) -v 2>&1
| grep -q "^Target: mips" && echo "yes" || echo "no")',
Nit: mips => mips-

https://chromiumcodereview.appspot.com/10268010/diff/5001/build/gyp_v8
File build/gyp_v8 (right):

https://chromiumcodereview.appspot.com/10268010/diff/5001/build/gyp_v8#newcod...
build/gyp_v8:172: gyp_args.append('-S-x64')
-x64 => .x64, same below

[Jakob Kummerow, 2012-05-03 08:11:02]

Landing.

https://chromiumcodereview.appspot.com/10268010/diff/5001/build/common.gypi
File build/common.gypi (right):

https://chromiumcodereview.appspot.com/10268010/diff/5001/build/common.gypi#n...
build/common.gypi:177: 'mipscompiler': '<!($(echo ${CXX:-$(which g++)}) -v 2>&1
| grep -q "^Target: mips" && echo "yes" || echo "no")',
On 2012/05/03 07:46:41, Sven Panne wrote:
> Nit: mips => mips-

Done.

https://chromiumcodereview.appspot.com/10268010/diff/5001/build/gyp_v8
File build/gyp_v8 (right):

https://chromiumcodereview.appspot.com/10268010/diff/5001/build/gyp_v8#newcod...
build/gyp_v8:172: gyp_args.append('-S-x64')
On 2012/05/03 07:46:41, Sven Panne wrote:
> -x64 => .x64, same below

Done.