The code reorganization in commit
4a6fd938 broke handling of PREFIX_ADR.
While fixing this, tidy and comment the code so that it's more obvious
what's going on in setting both aflag and dflag.
The TARGET_X86_64 ifdef can be eliminated because CODE64 expands to the
constant zero when TARGET_X86_64 is undefined.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Reported-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id:
1369855851-21400-1-git-send-email-rth@twiddle.net
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
(cherry picked from commit
dec3fc9657e0682637de4d5a29d947284d01985c)
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
}
s->pc = pc_start;
prefixes = 0;
}
s->pc = pc_start;
prefixes = 0;
- aflag = s->code32;
- dflag = s->code32;
s->override = -1;
rex_w = -1;
rex_r = 0;
s->override = -1;
rex_w = -1;
rex_r = 0;
}
/* Post-process prefixes. */
}
/* Post-process prefixes. */
- if (prefixes & PREFIX_DATA) {
- dflag ^= 1;
- }
- if (prefixes & PREFIX_ADR) {
- aflag ^= 1;
- }
-#ifdef TARGET_X86_64
- if (rex_w == 1) {
- /* 0x66 is ignored if rex.w is set */
- dflag = 2;
+ /* In 64-bit mode, the default data size is 32-bit. Select 64-bit
+ data with rex_w, and 16-bit data with 0x66; rex_w takes precedence
+ over 0x66 if both are present. */
+ dflag = (rex_w > 0 ? 2 : prefixes & PREFIX_DATA ? 0 : 1);
+ /* In 64-bit mode, 0x67 selects 32-bit addressing. */
+ aflag = (prefixes & PREFIX_ADR ? 1 : 2);
+ } else {
+ /* In 16/32-bit mode, 0x66 selects the opposite data size. */
+ dflag = s->code32;
+ if (prefixes & PREFIX_DATA) {
+ dflag ^= 1;
- if (!(prefixes & PREFIX_ADR)) {
- aflag = 2;
+ /* In 16/32-bit mode, 0x67 selects the opposite addressing. */
+ aflag = s->code32;
+ if (prefixes & PREFIX_ADR) {
+ aflag ^= 1;
s->prefix = prefixes;
s->aflag = aflag;
s->prefix = prefixes;
s->aflag = aflag;