[PATCH] libitm: Add custom HTM fast path for RTM on x86_64.

[Dominique Dhumieres]

> Committed as r202101.

This cause a bootstrap failure:

...
libtool: compile:  /opt/gcc/build_w/./gcc/xg++ -B/opt/gcc/build_w/./gcc/ -nostdinc++ -nostdinc++ -I/opt/gcc/build_w/x86_64-apple-darwin10.8.0/libstdc++-v3/include/x86_64-apple-darwin10.8.0 -I/opt/gcc/build_w/x86_64-apple-darwin10.8.0/libstdc++-v3/include -I/opt/gcc/work/libstdc++-v3/libsupc++ -I/opt/gcc/work/libstdc++-v3/include/backward -I/opt/gcc/work/libstdc++-v3/testsuite/util -L/opt/gcc/build_w/x86_64-apple-darwin10.8.0/libstdc++-v3/src -L/opt/gcc/build_w/x86_64-apple-darwin10.8.0/libstdc++-v3/src/.libs -L/opt/gcc/build_w/x86_64-apple-darwin10.8.0/libstdc++-v3/libsupc++/.libs -B/opt/gcc/gcc4.9w/x86_64-apple-darwin10.8.0/bin/ -B/opt/gcc/gcc4.9w/x86_64-apple-darwin10.8.0/lib/ -isystem /opt/gcc/gcc4.9w/x86_64-apple-darwin10.8.0/include -isystem /opt/gcc/gcc4.9w/x86_64-apple-darwin10.8.0/sys-include -DHAVE_CONFIG_H -I. -I../../../work/libitm -I../../../work/libitm/config/x86 -I../../../work/libitm/config/posix -I../../../work/libitm/config/generic -I../../../work/libitm -mrtm -Wall -pthread -Werror -std=gnu++0x -funwind-tables -fno-exceptions -fno-rtti -fabi-version=4 -g -O2 -MT rwlock.lo -MD -MP -MF .deps/rwlock.Tpo -c ../../../work/libitm/config/posix/rwlock.cc  -fno-common -DPIC -o .libs/rwlock.o
In file included from ../../../work/libitm/libitm_i.h:83:0,
                 from ../../../work/libitm/config/posix/rwlock.cc:25:
../../../work/libitm/config/posix/rwlock.h: In constructor 'GTM::gtm_rwlock::gtm_rwlock()':
../../../work/libitm/config/posix/rwlock.h:64:18: error: 'GTM::gtm_rwlock::c_confirmed_writers' will be initialized after [-Werror=reorder]
   pthread_cond_t c_confirmed_writers; // Writers wait here for readers
                  ^
../../../work/libitm/config/posix/rwlock.h:59:29: error:   'std::atomic<unsigned int> GTM::gtm_rwlock::summary' [-Werror=reorder]
   std::atomic<unsigned int> summary; // Bitmask of the above.
                             ^
../../../work/libitm/config/posix/rwlock.cc:32:1: error:   when initialized here [-Werror=reorder]
 gtm_rwlock::gtm_rwlock()
 ^
cc1plus: all warnings being treated as errors
make[4]: *** [rwlock.lo] Error 1
make[3]: *** [all-recursive] Error 1
make[2]: *** [all] Error 2
make[1]: *** [all-target-libitm] Error 2
make: *** [all] Error 2

on x86_64-apple-darwin10.

TIA

Dominique