[committed] i386: Clear vex instead of vex.evex

  I'd like to backport it to GDB 8.1 branch.  Is it OK  for gdb-8.1-branch?

H.J.
---------- Forwarded message ----------
From: H.J. Lu <hongjiu.lu@intel.com>
Date: Wed, Apr 4, 2018 at 4:42 AM
Subject: [PATCH, committed] i386: Clear vex instead of vex.evex
To: binutils@sourceware.org


"vex" has many fields to control how to decode an instruction.  Clear
all fields in "vex" before decoding an instruction to avoid using values
left from the previous instruction.

Checked into master and will backport it to 2.30 branch.

H.J.
----
gas/

        PR binutils/23025
        * testsuite/gas/i386/prefix.s: Add tests for vcvtpd2dq with
        VEX and EVEX prefixes.
        * testsuite/gas/i386/prefix.d: Updated.

opcodes/

        PR binutils/23025
        * i386-dis.c (get_valid_dis386): Don't set vex.prefix nor vex.w
        to 0.
        (print_insn): Clear vex instead of vex.evex.
---
 gas/ChangeLog                   | 7 +++++++
 gas/testsuite/gas/i386/prefix.d | 3 +++
 gas/testsuite/gas/i386/prefix.s | 4 ++++
 opcodes/ChangeLog               | 7 +++++++
 opcodes/i386-dis.c              | 7 +------
 5 files changed, 22 insertions(+), 6 deletions(-)

          vex.prefix = DATA_PREFIX_OPCODE;
@@ -12891,7 +12890,6 @@ get_valid_dis386 (const struct dis386 *dp,
disassemble_info *info)
       switch ((*codep & 0x3))
        {
        case 0:
-         vex.prefix = 0;
          break;
        case 1:
          vex.prefix = DATA_PREFIX_OPCODE;
@@ -12929,12 +12927,10 @@ get_valid_dis386 (const struct dis386 *dp,
disassemble_info *info)
       /* For the 2-byte VEX prefix in 32-bit mode, the highest bit in
         VEX.vvvv is 1.  */
       vex.register_specifier = (~(*codep >> 3)) & 0xf;
-      vex.w = 0;
       vex.length = (*codep & 0x4) ? 256 : 128;
       switch ((*codep & 0x3))
        {
        case 0:
-         vex.prefix = 0;
          break;
        case 1:
          vex.prefix = DATA_PREFIX_OPCODE;
@@ -13009,7 +13005,6 @@ get_valid_dis386 (const struct dis386 *dp,
disassemble_info *info)
       switch ((*codep & 0x3))
        {
        case 0:
-         vex.prefix = 0;
          break;
        case 1:
          vex.prefix = DATA_PREFIX_OPCODE;
@@ -13367,7 +13362,7 @@ print_insn (bfd_vma pc, disassemble_info *info)
   need_vex = 0;
   need_vex_reg = 0;
   vex_w_done = 0;
-  vex.evex = 0;
+  memset (&vex, 0, sizeof (vex));

   if (dp->name == NULL && dp->op[0].bytemode == FLOATCODE)
     {
--
2.14.3
  

> I'd like to backport it to GDB 8.1 branch.  Is it OK  for gdb-8.1-branch?

Looks good to me, but in that case, create a GDB PR that points
to the binutils one, and set the Target Milestone to 8.1. This is
to make sure all changes made on the 8.1 branch since the 8.1
release are easily trackable by everyone.
  

On Wed, Apr 4, 2018 at 7:43 AM, Joel Brobecker <brobecker@adacore.com> wrote:
>> I'd like to backport it to GDB 8.1 branch.  Is it OK  for gdb-8.1-branch?
>
> Looks good to me, but in that case, create a GDB PR that points
> to the binutils one, and set the Target Milestone to 8.1. This is
> to make sure all changes made on the 8.1 branch since the 8.1
> release are easily trackable by everyone.
>

Done:

https://sourceware.org/bugzilla/show_bug.cgi?id=23028
  

> > Looks good to me, but in that case, create a GDB PR that points
> > to the binutils one, and set the Target Milestone to 8.1. This is
> > to make sure all changes made on the 8.1 branch since the 8.1
> > release are easily trackable by everyone.
> 
> Done:
> https://sourceware.org/bugzilla/show_bug.cgi?id=23028

Perfect, thank you.