OpenE2K
/
binutils-gdb
12
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

x86: consistently print prefixes explicitly which are invalid with VEX etc 

All of data size, rep, lock, and rex prefixes are invalid with VEX- and
alike encoded insns. Make sure they get printed explicitly in all cases,
to signal the anomaly. With this, do away with "rex_ignored" - if there
is a rex prefix, we want to print it anyway for VEX etc (and there's
nothing "ignored" about it in the first place - such an instruction will
raise #UD).
This commit is contained in:
Jan Beulich 2020-06-09 08:59:04 +02:00
parent 18897deb53
commit 73239888b3
5 changed files with 26 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
gas/ChangeLog
View File

@ -1,3 +1,9 @@
2020-06-09 Jan Beulich <jbeulich@suse.com>
* testsuite/gas/i386/prefix.s: Add bogus prefix-with-VEX/EVEX
encoding tests.
* testsuite/gas/i386/prefix.d: Adjust expectations.
2020-06-09 Jan Beulich <jbeulich@suse.com>
* testsuite/gas/i386/prefix.s: Add bogus REP / EVEX.W prefix

5
gas/testsuite/gas/i386/prefix.d
View File

@ -86,8 +86,11 @@ Disassembly of section .text:
[ ]*[a-f0-9]+: ff cc dec %esp
[ ]*[a-f0-9]+: 62 f1 ff 08 28 \(bad\) *
[ ]*[a-f0-9]+: ff cc dec %esp
[ ]*[a-f0-9]+: 66 c5 f8 28 c0 data16 vmovaps %xmm0,%xmm0
[ ]*[a-f0-9]+: f3 c4 e1 78 28 c0 repz vmovaps %xmm0,%xmm0
[ ]*[a-f0-9]+: f2 c5 f8 28 c0 repnz vmovaps %xmm0,%xmm0
[ ]*[a-f0-9]+: f0 62 f1 7c 08 28 c0 lock vmovaps %xmm0,%xmm0
[ ]*[a-f0-9]+: c5 fb e6 40 20 vcvtpd2dqx 0x20\(%eax\),%xmm0
[ ]*[a-f0-9]+: 62 f1 ff 18 e6 40 04 vcvtpd2dq 0x20\(%eax\)\{1to2\},%xmm0
[ ]*[a-f0-9]+: c5 fb e6 40 20 vcvtpd2dqx 0x20\(%eax\),%xmm0
...
#pass

5
gas/testsuite/gas/i386/prefix.s
View File

@ -451,6 +451,11 @@
int $3
.byte 0x66; vmovaps %xmm0, %xmm0
repz; {vex3} vmovaps %xmm0, %xmm0
repnz; vmovaps %xmm0, %xmm0
lock; {evex} vmovaps %xmm0, %xmm0
vcvtpd2dqx 0x20(%eax),%xmm0
vcvtpd2dq 0x20(%eax){1to2},%xmm0
vcvtpd2dqx 0x20(%eax),%xmm0

8
opcodes/ChangeLog
View File

@ -1,3 +1,11 @@
2020-06-09 Jan Beulich <jbeulich@suse.com>
* i386-dis.c (rex_ignored): Delete.
(ckprefix): Drop rex_ignored initialization.
(get_valid_dis386): Drop setting of rex_ignored.
(print_insn): Drop checking of rex_ignored. Don't record data
size prefix as used with VEX-and-alike encodings.
2020-06-09 Jan Beulich <jbeulich@suse.com>
* i386-dis.c (MOD_0F12_PREFIX_2, MOD_0F16_PREFIX_2,

16
opcodes/i386-dis.c
View File

@ -153,8 +153,6 @@ static int prefixes;
static int rex;
/* Bits of REX we've already used. */
static int rex_used;
/* REX bits in original REX prefix ignored. */
static int rex_ignored;
/* Mark parts used in the REX prefix. When we are testing for
empty prefix (for 8bit register REX extension), just mask it
out. Otherwise test for REX bit is excuse for existence of REX
@ -11057,7 +11055,6 @@ ckprefix (void)
{
int newrex, i, length;
rex = 0;
rex_ignored = 0;
prefixes = 0;
used_prefixes = 0;
rex_used = 0;
@ -11517,8 +11514,6 @@ get_valid_dis386 (const struct dis386 *dp, disassemble_info *info)
case USE_XOP_8F_TABLE:
FETCH_DATA (info, codep + 3);
/* All bits in the REX prefix are ignored. */
rex_ignored = rex;
rex = ~(*codep >> 5) & 0x7;
/* VEX_TABLE_INDEX is the mmmmm part of the XOP byte 1 "RCB.mmmmm". */
@ -11580,8 +11575,6 @@ get_valid_dis386 (const struct dis386 *dp, disassemble_info *info)
case USE_VEX_C4_TABLE:
/* VEX prefix. */
FETCH_DATA (info, codep + 3);
/* All bits in the REX prefix are ignored. */
rex_ignored = rex;
rex = ~(*codep >> 5) & 0x7;
switch ((*codep & 0x1f))
{
@ -11647,8 +11640,6 @@ get_valid_dis386 (const struct dis386 *dp, disassemble_info *info)
case USE_VEX_C5_TABLE:
/* VEX prefix. */
FETCH_DATA (info, codep + 2);
/* All bits in the REX prefix are ignored. */
rex_ignored = rex;
rex = (*codep & 0x80) ? 0 : REX_R;
/* For the 2-byte VEX prefix in 32-bit mode, the highest bit in
@ -11697,8 +11688,6 @@ get_valid_dis386 (const struct dis386 *dp, disassemble_info *info)
/* EVEX prefix. */
vex.evex = 1;
FETCH_DATA (info, codep + 4);
/* All bits in the REX prefix are ignored. */
rex_ignored = rex;
/* The first byte after 0x62. */
rex = ~(*codep >> 5) & 0x7;
vex.r = *codep & 0x10;
@ -12179,7 +12168,7 @@ print_insn (bfd_vma pc, disassemble_info *info)
}
/* Check if the REX prefix is used. */
if (rex_ignored == 0 && (rex ^ rex_used) == 0 && last_rex_prefix >= 0)
if ((rex ^ rex_used) == 0 && !need_vex && last_rex_prefix >= 0)
all_prefixes[last_rex_prefix] = 0;
/* Check if the SEG prefix is used. */
@ -12195,7 +12184,8 @@ print_insn (bfd_vma pc, disassemble_info *info)
/* Check if the DATA prefix is used. */
if ((prefixes & PREFIX_DATA) != 0
&& (used_prefixes & PREFIX_DATA) != 0)
&& (used_prefixes & PREFIX_DATA) != 0
&& !need_vex)
all_prefixes[last_data_prefix] = 0;
/* Print the extra prefixes. */