https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65871
--- Comment #9 from James Almer <jamrial at gmail dot com> --- Created attachment 35804 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=35804&action=edit Preprocessed code where a test instruction is still generated Please look at the attachment. [jamrial@archVM ~]$ gcc -std=c99 -march=haswell -O3 -c hevc_ps.i [jamrial@archVM ~]$ objdump --disassemble hevc_ps.o | grep -B2 -A2 bzhi 5854: c4 62 22 f7 d6 sarx %r11d,%esi,%r10d 5859: c4 62 22 f7 da sarx %r11d,%edx,%r11d 585e: c4 e2 70 f5 f6 bzhi %ecx,%esi,%esi 5863: 45 89 9e 68 33 00 00 mov %r11d,0x3368(%r14) 586a: 41 89 c3 mov %eax,%r11d -- 589d: 85 f6 test %esi,%esi 589f: 75 0d jne 58ae <ff_hevc_decode_nal_sps+0x1a6e> 58a1: c4 e2 70 f5 d2 bzhi %ecx,%edx,%edx 58a6: 85 d2 test %edx,%edx 58a8: 0f 84 5a 03 00 00 je 5c08 <ff_hevc_decode_nal_sps+0x1dc8> [jamrial@archVM ~]$ gcc -v Using built-in specs. COLLECT_GCC=gcc COLLECT_LTO_WRAPPER=/usr/local/lib/gcc/x86_64-unknown-linux-gnu/6.0.0/lto-wrapper Target: x86_64-unknown-linux-gnu Configured with: /home/jamrial/gcc-svn/configure --prefix=/usr/local --libdir=/usr/local/lib --libexecdir=/usr/local/lib --mandir=/usr/local/share/man --infodir=/usr/local/share/info --enable-languages=c,c++,lto --enable-shared --disable-bootstrap --enable-threads=posix --enable-libmpx --with-system-zlib --enable-__cxa_atexit --disable-libunwind-exceptions --enable-clocale=gnu --disable-libstdcxx-pch --disable-libssp --enable-gnu-unique-object --enable-linker-build-id --enable-lto --enable-plugin --enable-install-libiberty --with-linker-hash-style=gnu --enable-gnu-indirect-function --disable-multilib --disable-werror Thread model: posix gcc version 6.0.0 20150618 (experimental) (GCC) Not sure why the new model is not working here.
