Utilize some of the additions in the prior patches to clean up other
code:
- keep track of REP prefixes in only one variable
- use REX_W in a few more places (instead of a literal number)
Signed-off-by: Jan Beulich <jbeulich@suse.com>
--- a/xen/arch/x86/x86_emulate/x86_emulate.c
+++ b/xen/arch/x86/x86_emulate/x86_emulate.c
@@ -304,6 +304,10 @@ union vex {
ptr[1] = rex | REX_PREFIX; \
} while (0)
+#define rep_prefix() (vex.pfx >= vex_f3)
+#define repe_prefix() (vex.pfx == vex_f3)
+#define repne_prefix() (vex.pfx == vex_f2)
+
/* Type, address-of, and value of an instruction''s operand. */
struct operand {
enum { OP_REG, OP_MEM, OP_IMM, OP_NONE } type;
@@ -734,7 +738,7 @@ static unsigned long __get_rep_prefix(
#define get_rep_prefix() ({ \
unsigned long max_reps = 1; \
- if ( rep_prefix ) \
+ if ( rep_prefix() ) \
max_reps = __get_rep_prefix(&_regs, ctxt->regs, ad_bytes);
\
if ( max_reps == 0 ) \
goto done; \
@@ -765,7 +769,7 @@ static void __put_rep_prefix(
}
#define put_rep_prefix(reps_completed) ({ \
- if ( rep_prefix ) \
+ if ( rep_prefix() ) \
__put_rep_prefix(&_regs, ctxt->regs, ad_bytes, reps_completed);
\
})
@@ -1328,9 +1332,7 @@ x86_emulate(
uint8_t modrm = 0, modrm_mod = 0, modrm_reg = 0, modrm_rm = 0;
union vex vex = {};
unsigned int op_bytes, def_op_bytes, ad_bytes, def_ad_bytes;
-#define REPE_PREFIX 1
-#define REPNE_PREFIX 2
- unsigned int lock_prefix = 0, rep_prefix = 0;
+ bool_t lock_prefix = 0;
int override_seg = -1, rc = X86EMUL_OKAY;
struct operand src, dst;
DECLARE_ALIGNED(mmval_t, mmval);
@@ -1359,7 +1361,8 @@ x86_emulate(
{
case 0x66: /* operand-size override */
op_bytes = def_op_bytes ^ 6;
- vex.pfx = vex_66;
+ if ( !vex.pfx )
+ vex.pfx = vex_66;
break;
case 0x67: /* address-size override */
ad_bytes = def_ad_bytes ^ (mode_64bit() ? 12 : 6);
@@ -1386,11 +1389,9 @@ x86_emulate(
lock_prefix = 1;
break;
case 0xf2: /* REPNE/REPNZ */
- rep_prefix = REPNE_PREFIX;
vex.pfx = vex_f2;
break;
case 0xf3: /* REP/REPE/REPZ */
- rep_prefix = REPE_PREFIX;
vex.pfx = vex_f3;
break;
case 0x40 ... 0x4f: /* REX */
@@ -1407,7 +1408,7 @@ x86_emulate(
}
done_prefixes:
- if ( rex_prefix & 8 ) /* REX.W */
+ if ( rex_prefix & REX_W )
op_bytes = 8;
/* Opcode byte(s). */
@@ -2418,8 +2419,8 @@ x86_emulate(
put_rep_prefix(1);
/* cmp: dst - src ==> src=*%%edi,dst=*%%esi ==> *%%esi - *%%edi
*/
emulate_2op_SrcV("cmp", src, dst, _regs.eflags);
- if ( ((rep_prefix == REPE_PREFIX) && !(_regs.eflags &
EFLG_ZF)) ||
- ((rep_prefix == REPNE_PREFIX) && (_regs.eflags &
EFLG_ZF)) )
+ if ( (repe_prefix() && !(_regs.eflags & EFLG_ZF)) ||
+ (repne_prefix() && (_regs.eflags & EFLG_ZF)) )
_regs.eip = next_eip;
break;
}
@@ -2464,8 +2465,8 @@ x86_emulate(
put_rep_prefix(1);
/* cmp: dst - src ==> src=*%%edi,dst=%%eax ==> %%eax - *%%edi */
emulate_2op_SrcV("cmp", src, dst, _regs.eflags);
- if ( ((rep_prefix == REPE_PREFIX) && !(_regs.eflags &
EFLG_ZF)) ||
- ((rep_prefix == REPNE_PREFIX) && (_regs.eflags &
EFLG_ZF)) )
+ if ( (repe_prefix() && !(_regs.eflags & EFLG_ZF)) ||
+ (repne_prefix() && (_regs.eflags & EFLG_ZF)) )
_regs.eip = next_eip;
break;
}
@@ -4076,7 +4077,7 @@ x86_emulate(
case 0x35: /* sysexit */ {
uint64_t msr_content;
struct segment_register cs, ss;
- int user64 = !!(rex_prefix & 8); /* REX.W */
+ bool_t user64 = !!(rex_prefix & REX_W);
int rc;
generate_exception_if(!mode_ring0(), EXC_GP, 0);
@@ -4366,7 +4367,7 @@ x86_emulate(
: "=r" (dst.val), "=q" (zf)
: "r" (src.val) );
_regs.eflags &= ~EFLG_ZF;
- if ( (rep_prefix == REPE_PREFIX) && vcpu_has_bmi1() )
+ if ( (vex.pfx == vex_f3) && vcpu_has_bmi1() )
{
_regs.eflags &= ~EFLG_CF;
if ( zf )
@@ -4391,7 +4392,7 @@ x86_emulate(
: "=r" (dst.val), "=q" (zf)
: "r" (src.val) );
_regs.eflags &= ~EFLG_ZF;
- if ( (rep_prefix == REPE_PREFIX) && vcpu_has_lzcnt() )
+ if ( (vex.pfx == vex_f3) && vcpu_has_lzcnt() )
{
_regs.eflags &= ~EFLG_CF;
if ( zf )
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