Re: [PATCH] x86: allow suffix-less movzw and 64-bit movzb

["H.J. Lu" <hjl dot tools at gmail dot com>]

On Thu, Jun 30, 2016 at 3:42 AM, Jan Beulich <JBeulich@suse.com> wrote:
> ... just like is already the case for 16- and 32-bit movzb: I can't see
> why omitting suffixes on this (and movs{b,w,l}) is not allowed, when it
> is allowed for all other instructions where the suffix is redundant
> with (one of) the operands.
>
> gas/testsuite/
> 2016-06-30  Jan Beulich  <jbeulich@suse.com>
>
>         * gas/i386/movz.s: New.
>         * gas/i386/movz32.d: New.
>         * gas/i386/movz64.d: New.
>         * gas/i386/i386.exp: Run new tests. Invoke as for 64-bits tests
>         with "--defsym x86_64=1 --strip-local-absolute".
>
> opcodes/
> 2016-06-30  Jan Beulich  <jbeulich@suse.com>
>
>         * i386-opc.tbl (movzbl, movzbw, movzbq, movzwl, movzwq): Remove.
>         (movzb): Adjust to cover all permitted suffixes.
>         (movzw): New.
>         * i386-tbl.h: Re-generate.
>
> --- 2016-06-30/gas/testsuite/gas/i386/i386.exp  2016-06-30 11:25:50.000000000 +0200
> +++ 2016-06-30/gas/testsuite/gas/i386/i386.exp  2016-06-30 12:04:26.000000000 +0200
> @@ -59,6 +59,7 @@ if [expr ([istarget "i*86-*-*"] ||  [ist
>      run_dump_test "amd"
>      run_dump_test "katmai"
>      run_dump_test "jump"
> +    run_dump_test "movz32"
>      run_dump_test "relax-1"
>      run_dump_test "relax-2"
>      run_dump_test "ssemmx2"
> @@ -482,7 +483,7 @@ if [expr ([istarget "i*86-*-*"] || [ista
>
>      global ASFLAGS
>      set old_ASFLAGS "$ASFLAGS"
> -    set ASFLAGS "$ASFLAGS --64"
> +    set ASFLAGS "$ASFLAGS --64 --defsym x86_64=1 --strip-local-absolute"
>
>      run_dump_test "x86_64"
>      run_dump_test "x86_64-intel"
> @@ -506,6 +507,7 @@ if [expr ([istarget "i*86-*-*"] || [ista
>      run_dump_test "x86-64-segovr"
>      run_list_test "x86-64-inval-seg" "-al"
>      run_dump_test "x86-64-branch"
> +    run_dump_test "movz64"
>      run_dump_test "x86-64-relax-1"
>      run_dump_test "svme64"
>      run_dump_test "x86-64-amdfam10"
> --- 2016-06-30/gas/testsuite/gas/i386/movz.s    1970-01-01 01:00:00.000000000 +0100
> +++ 2016-06-30/gas/testsuite/gas/i386/movz.s    2016-06-30 12:04:26.000000000 +0200
> @@ -0,0 +1,33 @@
> +       .text
> +movz:
> +       movzb   %al,%ax
> +       movzb   (%eax),%ax
> +       movzb   %al,%eax
> +       movzb   (%eax),%eax
> +.ifdef x86_64
> +       movzb   %al,%rax
> +       movzb   (%rax),%rax
> +.endif
> +
> +       movzbw  %al,%ax
> +       movzbw  (%eax),%ax
> +       movzbl  %al,%eax
> +       movzbl  (%eax),%eax
> +.ifdef x86_64
> +       movzbq  %al,%rax
> +       movzbq  (%rax),%rax
> +.endif
> +
> +       movzw   %ax,%eax
> +       movzw   (%eax),%eax
> +.ifdef x86_64
> +       movzw   %ax,%rax
> +       movzw   (%rax),%rax
> +.endif
> +
> +       movzwl  %ax,%eax
> +       movzwl  (%eax),%eax
> +.ifdef x86_64
> +       movzwq  %ax,%rax
> +       movzwq  (%rax),%rax
> +.endif
> --- 2016-06-30/gas/testsuite/gas/i386/movz32.d  1970-01-01 01:00:00.000000000 +0100
> +++ 2016-06-30/gas/testsuite/gas/i386/movz32.d  2016-06-30 12:04:26.000000000 +0200
> @@ -0,0 +1,22 @@
> +#objdump: -d
> +#source: movz.s
> +#name: x86 mov with zero-extend (32-bit object)
> +
> +.*: +file format .*
> +
> +Disassembly of section .text:
> +
> +0+ <movz>:
> +[      ]*[a-f0-9]+:    66 0f b6 c0 *   movzbw? %al,%ax
                                                                 ^

What is `?' for?



-- 
H.J.