The IsPowerOfTwo function is used together with ShiftForPowerOfTwo. Both function
do not work with zero. This caused the optimizing compiler to generate invalid code
for the expression
x ? 0 : 0
where it assumed that if one of the constants is a power-of-two, it can
be computed by (1 << n). We check for 0 in a number of places, but instead
I decided to fix Utils::IsPowerOfTwo itself and remove unnecessary checks
for the zero case.
TEST=tests/language/vm/if_conversion_vm_test.dart, runtime/vm/utils_test.cc
R=kmillikin@google.com
Review URL: https://codereview.chromium.org//23604024
git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@27033 260f80e4-7a28-3924-810f-c04153c831b5
Split directory_posix -> directory_(android|linux|macos)
This allows us to cleanly make Android-specific changes to
directory_android.cc
Copy all _linux files to _android files and edit as needed to account
for the differences between Linux and Android:
+ getcwd(0, NULL) doesn't work on Android, have to emulate
+ Android doesn't have a '/tmp' directory, have to emulate
+ Android doesn't provide mkdtemp(), have to emulate.
+ Small differences in the available system include files.
+ Use pthread_cond_timedwait_monotonic instead of
pthread_condattr_setclock
Review URL: https://chromiumcodereview.appspot.com//10826233
git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@10613 260f80e4-7a28-3924-810f-c04153c831b5
fschneider@google.com