pass_insert_vzeroupper is under condition
TARGET_AVX && TARGET_VZEROUPPER
&& flag_expensive_optimizations && !optimize_size
But the document of mvzeroupper doesn't mention the insertion
required -O2 and above, it may confuse users when they explicitly
use -Os -mvzeroupper.
------------
mvzeroupper
Target Mask(VZEROUPPER) Save
Generate vzeroupper instruction before a transfer of control flow out of
the function.
------------
The patch moves flag_expensive_optimizations && !optimize_size to
ix86_option_override_internal. It makes -mvzeroupper independent of
optimization level, but still keeps the behavior of architecture
tuning(emit_vzeroupper) unchanged.
gcc/ChangeLog:
* config/i386/i386-features.c (pass_insert_vzeroupper:gate):
Move flag_expensive_optimizations && !optimize_size to ..
* config/i386/i386-options.c (ix86_option_override_internal):
.. this, it makes -mvzeroupper independent of optimization
level, but still keeps the behavior of architecture
tuning(emit_vzeroupper) unchanged.
(rest_of_handle_insert_vzeroupper): Remove
flag_expensive_optimizations && !optimize_size.
gcc/testsuite/ChangeLog:
* gcc.target/i386/avx-vzeroupper-29.c: New testcase.
This directory contains machine-specific files for the GNU C compiler.
It has a subdirectory for each basic CPU type.
The only files in this directory itself
are some .h files that pertain to particular operating systems
and are used for more than one CPU type.
8cf948e6d9