The k6-2 processor doesn't support the nopl and nopw instructions with the code 0f 1f. Therefore, gas shouldn't use this instruction for alignment with -march=k6_2 Example - compile the following source file with "as -march=k6_2 --32" .global main main: xorl %eax, %eax .balign 8 ret The result: 00000000 <main>: 0: 31 c0 xor %eax,%eax 2: 66 0f 1f 44 00 00 nopw 0x0(%eax,%eax,1) 8: c3 ret
Fixed for master and 2.24: https://sourceware.org/git/?p=binutils-gdb.git;a=commitdiff;h=d56da83e58816c45a4bc70503776a6e62a66bf89
via 9f4e1fadf3e75b8aa37744d2b06b29f8d6d1ca93 (commit) from 1d5dce8548bb3702e3f4a7672d1493a032a4c85c (commit) Those revisions listed above that are new to this repository have not appeared on any other notification email; so we list those revisions in full, below. - Log ----------------------------------------------------------------- https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=9f4e1fadf3e75b8aa37744d2b06b29f8d6d1ca93 commit 9f4e1fadf3e75b8aa37744d2b06b29f8d6d1ca93 Author: H.J. Lu <hjl.tools@gmail.com> Date: Fri Nov 8 09:42:08 2013 -0800 Remove CpuNop from CPU_K6_2_FLAGS PR gas/16140 * i386-gen.c (cpu_flag_init): Remove CpuNop from CPU_K6_2_FLAGS. * i386-init.h: Regenerated. ----------------------------------------------------------------------- Summary of changes: opcodes/ChangeLog | 6 ++++++ opcodes/i386-gen.c | 2 +- opcodes/i386-init.h | 2 +- 3 files changed, 8 insertions(+), 2 deletions(-)
via d56da83e58816c45a4bc70503776a6e62a66bf89 (commit) from 94d60ebd791e53124a664cdd534920c218b57b08 (commit) Those revisions listed above that are new to this repository have not appeared on any other notification email; so we list those revisions in full, below. - Log ----------------------------------------------------------------- https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=d56da83e58816c45a4bc70503776a6e62a66bf89 commit d56da83e58816c45a4bc70503776a6e62a66bf89 Author: H.J. Lu <hjl.tools@gmail.com> Date: Fri Nov 8 09:42:08 2013 -0800 Remove CpuNop from CPU_K6_2_FLAGS PR gas/16140 * i386-gen.c (cpu_flag_init): Remove CpuNop from CPU_K6_2_FLAGS. * i386-init.h: Regenerated. ----------------------------------------------------------------------- Summary of changes: opcodes/ChangeLog | 6 ++++++ opcodes/i386-gen.c | 2 +- opcodes/i386-init.h | 2 +- 3 files changed, 8 insertions(+), 2 deletions(-)