GNU assembler (GNU Binutils for Ubuntu) 2.26.1 Copyright (C) 2015 Free Software Foundation, Inc. This program is free software; you may redistribute it under the terms of the GNU General Public License version 3 or later. This program has absolutely no warranty. This assembler was configured for a target of `x86_64-linux-gnu'.

Usage: as [option...] [asmfile...] Options: -a[sub-option...] turn on listings Sub-options [default hls]: c omit false conditionals d omit debugging directives g include general info h include high-level source l include assembly m include macro expansions n omit forms processing s include symbols =FILE list to FILE (must be last sub-option) --alternate initially turn on alternate macro syntax --compress-debug-sections[={none|zlib|zlib-gnu|zlib-gabi}] compress DWARF debug sections using zlib --nocompress-debug-sections don't compress DWARF debug sections [default] -D produce assembler debugging messages --debug-prefix-map OLD=NEW map OLD to NEW in debug information --defsym SYM=VAL define symbol SYM to given value --execstack require executable stack for this object --noexecstack don't require executable stack for this object --size-check=[error|warning] ELF .size directive check (default --size-check=error) --sectname-subst enable section name substitution sequences -f skip whitespace and comment preprocessing -g --gen-debug generate debugging information --gstabs generate STABS debugging information --gstabs+ generate STABS debug info with GNU extensions --gdwarf-2 generate DWARF2 debugging information --gdwarf-sections generate per-function section names for DWARF line information --hash-size=<value> set the hash table size close to <value> --help show this message and exit --target-help show target specific options -I DIR add DIR to search list for .include directives -J don't warn about signed overflow -K warn when differences altered for long displacements -L,--keep-locals keep local symbols (e.g. starting with `L') -M,--mri assemble in MRI compatibility mode --MD FILE write dependency information in FILE (default none) -nocpp ignored -o OBJFILE name the object-file output OBJFILE (default a.out) -R fold data section into text section --reduce-memory-overheads prefer smaller memory use at the cost of longer assembly times --statistics print various measured statistics from execution --strip-local-absolute strip local absolute symbols --traditional-format Use same format as native assembler when possible --version print assembler version number and exit -W --no-warn suppress warnings --warn don't suppress warnings --fatal-warnings treat warnings as errors -w ignored -X ignored -Z generate object file even after errors --listing-lhs-width set the width in words of the output data column of the listing --listing-lhs-width2 set the width in words of the continuation lines of the output data column; ignored if smaller than the width of the first line --listing-rhs-width set the max width in characters of the lines from the source file --listing-cont-lines set the maximum number of continuation lines used for the output data column of the listing @FILE read options from FILE -Q ignored -V print assembler version number -k ignored -n Do not optimize code alignment -q quieten some warnings -s ignored --32/--64/--x32 generate 32bit/64bit/x32 code --divide ignored -march=CPU[,+EXTENSION...] generate code for CPU and EXTENSION, CPU is one of: generic32, generic64, i386, i486, i586, i686, pentium, pentiumpro, pentiumii, pentiumiii, pentium4, prescott, nocona, core, core2, corei7, l1om, k1om, iamcu, k6, k6_2, athlon, opteron, k8, amdfam10, bdver1, bdver2, bdver3, bdver4, znver1, btver1, btver2 EXTENSION is combination of: 8087, 287, 387, no87, mmx, nommx, sse, sse2, sse3, ssse3, sse4.1, sse4.2, sse4, nosse, avx, avx2, avx512f, avx512cd, avx512er, avx512pf, avx512dq, avx512bw, avx512vl, noavx, vmx, vmfunc, smx, xsave, xsaveopt, xsavec, xsaves, aes, pclmul, fsgsbase, rdrnd, f16c, bmi2, fma, fma4, xop, lwp, movbe, cx16, ept, lzcnt, hle, rtm, invpcid, clflush, nop, syscall, rdtscp, 3dnow, 3dnowa, padlock, svme, sse4a, abm, bmi, tbm, adx, rdseed, prfchw, smap, mpx, sha, clflushopt, prefetchwt1, se1, clwb, pcommit, avx512ifma, avx512vbmi, clzero, mwaitx, ospke -mtune=CPU optimize for CPU, CPU is one of: generic32, generic64, i8086, i186, i286, i386, i486, i586, i686, pentium, pentiumpro, pentiumii, pentiumiii, pentium4, prescott, nocona, core, core2, corei7, l1om, k1om, iamcu, k6, k6_2, athlon, opteron, k8, amdfam10, bdver1, bdver2, bdver3, bdver4, znver1, btver1, btver2 -msse2avx encode SSE instructions with VEX prefix -msse-check=[none|error|warning] check SSE instructions -moperand-check=[none|error|warning] check operand combinations for validity -mavxscalar=[128|256] encode scalar AVX instructions with specific vector length -mevexlig=[128|256|512] encode scalar EVEX instructions with specific vector length -mevexwig=[0|1] encode EVEX instructions with specific EVEX.W value for EVEX.W bit ignored instructions -mevexrcig=[rne|rd|ru|rz] encode EVEX instructions with specific EVEX.RC value for SAE-only ignored instructions -mmnemonic=[att|intel] use AT&T/Intel mnemonic -msyntax=[att|intel] use AT&T/Intel syntax -mindex-reg support pseudo index registers -mnaked-reg don't require `%' prefix for registers -mold-gcc support old (<= 2.8.1) versions of gcc -madd-bnd-prefix add BND prefix for all valid branches -mshared disable branch optimization for shared code -momit-lock-prefix=[no|yes] strip all lock prefixes -mrelax-relocations=[no|yes] generate relax relocations -mamd64 accept only AMD64 ISA -mintel64 accept only Intel64 ISA Report bugs to <http://www.sourceware.org/bugzilla/>