Как проект GNU работает с кодами машинных команд?

$ i386-gen
bash: i386-gen: command not found

$ equery files binutils | grep "^/usr/x86_64-pc-linux-gnu/binutils-bin/"
/usr/x86_64-pc-linux-gnu/binutils-bin/2.40/addr2line
/usr/x86_64-pc-linux-gnu/binutils-bin/2.40/ar
/usr/x86_64-pc-linux-gnu/binutils-bin/2.40/as
/usr/x86_64-pc-linux-gnu/binutils-bin/2.40/c++filt
/usr/x86_64-pc-linux-gnu/binutils-bin/2.40/elfedit
/usr/x86_64-pc-linux-gnu/binutils-bin/2.40/gprof
/usr/x86_64-pc-linux-gnu/binutils-bin/2.40/ld
/usr/x86_64-pc-linux-gnu/binutils-bin/2.40/ld.bfd
/usr/x86_64-pc-linux-gnu/binutils-bin/2.40/nm
/usr/x86_64-pc-linux-gnu/binutils-bin/2.40/objcopy
/usr/x86_64-pc-linux-gnu/binutils-bin/2.40/objdump
/usr/x86_64-pc-linux-gnu/binutils-bin/2.40/ranlib
/usr/x86_64-pc-linux-gnu/binutils-bin/2.40/readelf
/usr/x86_64-pc-linux-gnu/binutils-bin/2.40/size
/usr/x86_64-pc-linux-gnu/binutils-bin/2.40/strings
/usr/x86_64-pc-linux-gnu/binutils-bin/2.40/strip

sys-libs/binutils-libs
--  sys-libs/zlib
--  sys-devel/binutils-config
--  sys-devel/gettext
--  dev-util/dejagnu
--  app-portage/elt-patches

#include <stdio.h>

asm(".global test\n"
    "test:\n"
    /* Clear the carry flag so that the following "jc" does not jump. */
    "clc\n"
    /* "66 0f 82" is the encoding for "data16 jc".  "jc" is also known
       as "jb".  On x86-32, this takes a 2-byte operand, so it
       executes "jmp size2".  On x86-64, this takes a 4-byte operand,
       so it executes "jmp size4". */
    ".ascii \"\\x66\\x0f\\x82\\x00\\x00\"\n"
    /* We assume that this jump is encoded as a 2-byte instruction. */
    "jmp size2\n"
    "jmp size4\n"
    "size2: jmp size_is_2\n"
    "size4: jmp size_is_4\n"
    );
void test(void);

void size_is_2() { printf("operand size is 2 bytes\n"); }
void size_is_4() { printf("operand size is 4 bytes\n"); }

int main() {
  test();
  return 0;
}

# На Intel
$ gcc test.c -o test -m64 && ./test
operand size is 4 bytes
# На AMD
$ gcc test.c -o test -m64 && ./test
operand size is 2 bytes

 for arch in $selarchs
    do
	ad=`echo $arch | sed -e s/bfd_//g -e s/_arch//g`
	archdefs="$archdefs -DARCH_$ad"
	case "$arch" in
	bfd_aarch64_arch)	ta="$ta aarch64-asm.lo aarch64-dis.lo aarch64-opc.lo aarch64-asm-2.lo aarch64-dis-2.lo aarch64-opc-2.lo" ;;
	bfd_alpha_arch)		ta="$ta alpha-dis.lo alpha-opc.lo" ;;
	bfd_arc_arch)		ta="$ta arc-dis.lo arc-opc.lo arc-ext.lo" ;;
	bfd_arm_arch)		ta="$ta arm-dis.lo" ;;
	bfd_avr_arch)		ta="$ta avr-dis.lo" ;;
	bfd_bfin_arch)		ta="$ta bfin-dis.lo" ;;
	bfd_cr16_arch)		ta="$ta cr16-dis.lo cr16-opc.lo" ;;
	bfd_cris_arch)		ta="$ta cris-desc.lo cris-dis.lo cris-opc.lo cgen-bitset.lo" ;;
	bfd_crx_arch)		ta="$ta crx-dis.lo crx-opc.lo" ;;
	bfd_csky_arch)		ta="$ta csky-dis.lo" ;;
	bfd_d10v_arch)		ta="$ta d10v-dis.lo d10v-opc.lo" ;;
	bfd_d30v_arch)		ta="$ta d30v-dis.lo d30v-opc.lo" ;;
	bfd_dlx_arch)		ta="$ta dlx-dis.lo" ;;
	bfd_fr30_arch)		ta="$ta fr30-asm.lo fr30-desc.lo fr30-dis.lo fr30-ibld.lo fr30-opc.lo" using_cgen=yes ;;
	bfd_frv_arch)		ta="$ta frv-asm.lo frv-desc.lo frv-dis.lo frv-ibld.lo frv-opc.lo" using_cgen=yes ;;
	bfd_ft32_arch)		ta="$ta ft32-opc.lo ft32-dis.lo" ;;
	bfd_moxie_arch)		ta="$ta moxie-dis.lo moxie-opc.lo" ;;
	bfd_h8300_arch)		ta="$ta h8300-dis.lo" ;;
	bfd_hppa_arch)		ta="$ta hppa-dis.lo" ;;
	bfd_i386_arch|bfd_iamcu_arch|bfd_l1om_arch|bfd_k1om_arch)
				ta="$ta i386-dis.lo i386-opc.lo" ;;
	bfd_ia64_arch)		ta="$ta ia64-dis.lo ia64-opc.lo" ;;
	bfd_ip2k_arch)		ta="$ta ip2k-asm.lo ip2k-desc.lo ip2k-dis.lo ip2k-ibld.lo ip2k-opc.lo" using_cgen=yes ;;
	bfd_epiphany_arch)	ta="$ta epiphany-asm.lo epiphany-desc.lo epiphany-dis.lo epiphany-ibld.lo epiphany-opc.lo" using_cgen=yes ;;
	bfd_iq2000_arch)	ta="$ta iq2000-asm.lo iq2000-desc.lo iq2000-dis.lo iq2000-ibld.lo iq2000-opc.lo" using_cgen=yes ;;
	bfd_lm32_arch)		ta="$ta lm32-asm.lo lm32-desc.lo lm32-dis.lo lm32-ibld.lo lm32-opc.lo lm32-opinst.lo" using_cgen=yes ;;
	bfd_m32c_arch)		ta="$ta m32c-asm.lo m32c-desc.lo m32c-dis.lo m32c-ibld.lo m32c-opc.lo" using_cgen=yes ;;
	bfd_m32r_arch)		ta="$ta m32r-asm.lo m32r-desc.lo m32r-dis.lo m32r-ibld.lo m32r-opc.lo m32r-opinst.lo" using_cgen=yes ;;
	bfd_m68hc11_arch)	ta="$ta m68hc11-dis.lo m68hc11-opc.lo" ;;
	bfd_m68hc12_arch)	ta="$ta m68hc11-dis.lo m68hc11-opc.lo" ;;
	bfd_m9s12x_arch)	ta="$ta m68hc11-dis.lo m68hc11-opc.lo" ;;
	bfd_m9s12xg_arch)	ta="$ta m68hc11-dis.lo m68hc11-opc.lo" ;;
	bfd_s12z_arch)		ta="$ta s12z-dis.lo s12z-opc.lo" ;;
	bfd_m68k_arch)		ta="$ta m68k-dis.lo m68k-opc.lo" ;;
	bfd_mcore_arch)		ta="$ta mcore-dis.lo" ;;
	bfd_mep_arch)		ta="$ta mep-asm.lo mep-desc.lo mep-dis.lo mep-ibld.lo mep-opc.lo" using_cgen=yes ;;
	bfd_metag_arch)		ta="$ta metag-dis.lo" ;;
	bfd_microblaze_arch)	ta="$ta microblaze-dis.lo" ;;
	bfd_mips_arch)		ta="$ta mips-dis.lo mips-opc.lo mips16-opc.lo micromips-opc.lo" ;;
	bfd_mmix_arch)		ta="$ta mmix-dis.lo mmix-opc.lo" ;;
	bfd_mn10200_arch)	ta="$ta m10200-dis.lo m10200-opc.lo" ;;
	bfd_mn10300_arch)	ta="$ta m10300-dis.lo m10300-opc.lo" ;;
	bfd_mt_arch)		ta="$ta mt-asm.lo mt-desc.lo mt-dis.lo mt-ibld.lo mt-opc.lo" using_cgen=yes ;;
	bfd_msp430_arch)	ta="$ta msp430-dis.lo msp430-decode.lo" ;;
	bfd_nds32_arch)		ta="$ta nds32-asm.lo nds32-dis.lo" ;;
	bfd_nfp_arch)		ta="$ta nfp-dis.lo" ;;
	bfd_nios2_arch)		ta="$ta nios2-dis.lo nios2-opc.lo" ;;
	bfd_ns32k_arch)		ta="$ta ns32k-dis.lo" ;;
	bfd_or1k_arch)		ta="$ta or1k-asm.lo or1k-desc.lo or1k-dis.lo or1k-ibld.lo or1k-opc.lo" using_cgen=yes ;;
	bfd_pdp11_arch)		ta="$ta pdp11-dis.lo pdp11-opc.lo" ;;
	bfd_pj_arch)		ta="$ta pj-dis.lo pj-opc.lo" ;;
	bfd_powerpc_arch)	ta="$ta ppc-dis.lo ppc-opc.lo" ;;
	bfd_powerpc_64_arch)	ta="$ta ppc-dis.lo ppc-opc.lo" ;;
	bfd_pru_arch)		ta="$ta pru-dis.lo pru-opc.lo" ;;
	bfd_pyramid_arch)	;;
	bfd_romp_arch)		;;
	bfd_riscv_arch)         ta="$ta riscv-dis.lo riscv-opc.lo" ;;
	bfd_rs6000_arch)	ta="$ta ppc-dis.lo ppc-opc.lo" ;;
	bfd_rl78_arch)		ta="$ta rl78-dis.lo rl78-decode.lo";;
	bfd_rx_arch)		ta="$ta rx-dis.lo rx-decode.lo";;
	bfd_s390_arch)		ta="$ta s390-dis.lo s390-opc.lo" ;;
	bfd_score_arch)		ta="$ta score-dis.lo score7-dis.lo" ;;
	bfd_sh_arch)		ta="$ta sh-dis.lo cgen-bitset.lo" ;;
	bfd_sparc_arch)		ta="$ta sparc-dis.lo sparc-opc.lo" ;;
	bfd_spu_arch)		ta="$ta spu-dis.lo spu-opc.lo" ;;
	bfd_tic30_arch)		ta="$ta tic30-dis.lo" ;;
	bfd_tic4x_arch)		ta="$ta tic4x-dis.lo" ;;
	bfd_tic54x_arch)	ta="$ta tic54x-dis.lo tic54x-opc.lo" ;;
	bfd_tic6x_arch)		ta="$ta tic6x-dis.lo" ;;
	bfd_tilegx_arch)	ta="$ta tilegx-dis.lo tilegx-opc.lo" ;;
	bfd_tilepro_arch)	ta="$ta tilepro-dis.lo tilepro-opc.lo" ;;
	bfd_v850_arch)		ta="$ta v850-opc.lo v850-dis.lo" ;;
	bfd_v850e_arch)		ta="$ta v850-opc.lo v850-dis.lo" ;;
	bfd_v850ea_arch)	ta="$ta v850-opc.lo v850-dis.lo" ;;
	bfd_v850_rh850_arch)	ta="$ta v850-opc.lo v850-dis.lo" ;;
	bfd_vax_arch)		ta="$ta vax-dis.lo" ;;
	bfd_visium_arch)	ta="$ta visium-dis.lo visium-opc.lo" ;;
        bfd_wasm32_arch)        ta="$ta wasm32-dis.lo" ;;
	bfd_xc16x_arch)		ta="$ta xc16x-asm.lo xc16x-desc.lo xc16x-dis.lo xc16x-ibld.lo xc16x-opc.lo" using_cgen=yes ;;
	bfd_xgate_arch)		ta="$ta xgate-dis.lo xgate-opc.lo" ;;
	bfd_xstormy16_arch)	ta="$ta xstormy16-asm.lo xstormy16-desc.lo xstormy16-dis.lo xstormy16-ibld.lo xstormy16-opc.lo" using_cgen=yes ;;
	bfd_xtensa_arch)	ta="$ta xtensa-dis.lo" ;;
	bfd_z80_arch)		ta="$ta z80-dis.lo" ;;
	bfd_z8k_arch)		ta="$ta z8k-dis.lo" ;;
	bfd_bpf_arch)		ta="$ta bpf-asm.lo bpf-desc.lo bpf-dis.lo bpf-ibld.lo bpf-opc.lo" using_cgen=yes ;;
	bfd_loongarch_arch)	ta="$ta loongarch-dis.lo loongarch-opc.lo loongarch-coder.lo" ;;

	"")			;;
	*)		AC_MSG_ERROR(*** unknown target architecture $arch) ;;
	esac
    done