/*
* x86 integer helpers
*
* Copyright (c) 2003 Fabrice Bellard
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include "cpu.h"
#include "qemu/host-utils.h"
#include "helper.h"
//#define DEBUG_MULDIV
/* modulo 17 table */
static const uint8_t rclw_table[32] = {
0, 1, 2, 3, 4, 5, 6, 7,
8, 9,10,11,12,13,14,15,
16, 0, 1, 2, 3, 4, 5, 6,
7, 8, 9,10,11,12,13,14,
};
/* modulo 9 table */
static const uint8_t rclb_table[32] = {
0, 1, 2, 3, 4, 5, 6, 7,
8, 0, 1, 2, 3, 4, 5, 6,
7, 8, 0, 1, 2, 3, 4, 5,
6, 7, 8, 0, 1, 2, 3, 4,
};
/* division, flags are undefined */
void helper_divb_AL(CPUX86State *env, target_ulong t0)
{
unsigned int num, den, q, r;
num = (EAX & 0xffff);
den = (t0 & 0xff);
if (den == 0) {
raise_exception(env, EXCP00_DIVZ);
}
q = (num / den);
if (q > 0xff)
raise_exception(env, EXCP00_DIVZ);
q &= 0xff;
r = (num % den) & 0xff;
EAX = (EAX & ~0xffff) | (r << 8) | q;
}
void helper_idivb_AL(CPUX86State *env, target_ulong t0)
{
int num, den, q, r;
num = (int16_t)EAX;
den = (int8_t)t0;
if (den == 0) {
raise_exception(env, EXCP00_DIVZ);
}
q = (num / den);
if (q != (int8_t)q)
raise_exception(env, EXCP00_DIVZ);
q &= 0xff;
r = (num % den) & 0xff;
EAX = (EAX & ~0xffff) | (r << 8) | q;
}
void helper_divw_AX(CPUX86State *env, target_ulong t0)
{
unsigned int num, den, q, r;
num = (EAX & 0xffff) | ((EDX & 0xffff) << 16);
den = (t0 & 0xffff);
if (den == 0) {
raise_exception(env, EXCP00_DIVZ);
}
q = (num / den);
if (q > 0xffff)
raise_exception(env, EXCP00_DIVZ);
q &= 0xffff;
r = (num % den) & 0xffff;
EAX = (EAX & ~0xffff) | q;
EDX = (EDX & ~0xffff) | r;
}
void helper_idivw_AX(CPUX86State *env, target_ulong t0)
{
int num, den, q, r;
num = (EAX & 0xffff) | ((EDX & 0xffff) << 16);
den = (int16_t)t0;
if (den == 0) {
raise_exception(env, EXCP00_DIVZ);
}
q = (num / den);
if (q != (int16_t)q)
raise_exception(env, EXCP00_DIVZ);
q &= 0xffff;
r = (num % den) & 0xffff;
EAX = (EAX & ~0xffff) | q;
EDX = (EDX & ~0xffff) | r;
}
void helper_divl_EAX(CPUX86State *env, target_ulong t0)
{
unsigned int den, r;
uint64_t num, q;
num = ((uint32_t)EAX) | ((uint64_t)((uint32_t)EDX) << 32);
den = t0;
if (den == 0) {
raise_exception(env, EXCP00_DIVZ);
}
q = (num / den);
r = (num % den);
if (q > 0xffffffff)
raise_exception(env, EXCP00_DIVZ);
EAX = (uint32_t)q;
EDX = (uint32_t)r;
}
void helper_idivl_EAX(CPUX86State *env, target_ulong t0)
{
int den, r;
int64_t num, q;
num = ((uint32_t)EAX) | ((uint64_t)((uint32_t)EDX) << 32);
den = t0;
if (den == 0) {
raise_exception(env, EXCP00_DIVZ);
}
q = (num / den);
r = (num % den);
if (q != (int32_t)q)
raise_exception(env, EXCP00_DIVZ);
EAX = (uint32_t)q;
EDX = (uint32_t)r;
}
/* bcd */
/* XXX: exception */
void helper_aam(CPUX86State *env, int base)
{
int al, ah;
al = EAX & 0xff;
ah = al / base;
al = al % base;
EAX = (EAX & ~0xffff) | al | (ah << 8);
CC_DST = al;
}
void helper_aad(CPUX86State *env, int base)
{
int al, ah;
al = EAX & 0xff;
ah = (EAX >> 8) & 0xff;
al = ((ah * base) + al) & 0xff;
EAX = (EAX & ~0xffff) | al;
CC_DST = al;
}
void helper_aaa(CPUX86State *env)
{
int icarry;
int al, ah, af;
int eflags;
eflags = helper_cc_compute_all(env, CC_OP);
af = eflags & CC_A;
al = EAX & 0xff;
ah = (EAX >> 8) & 0xff;
icarry = (al > 0xf9);
if (((al & 0x0f) > 9 ) || af) {
al = (al + 6) & 0x0f;
ah = (ah + 1 + icarry) & 0xff;
eflags |= CC_C | CC_A;
} else {
eflags &= ~(CC_C | CC_A);
al &= 0x0f;
}
EAX = (EAX & ~0xffff) | al | (ah << 8);
CC_SRC = eflags;
}
void helper_aas(CPUX86State *env)
{
int icarry;
int al, ah, af;
int eflags;
eflags = helper_cc_compute_all(env, CC_OP);
af = eflags & CC_A;
al = EAX & 0xff;
ah = (EAX >> 8) & 0xff;
icarry = (al < 6);
if (((al & 0x0f) > 9 ) || af) {
al = (al - 6) & 0x0f;
ah = (ah - 1 - icarry) & 0xff;
eflags |= CC_C | CC_A;
} else {
eflags &= ~(CC_C | CC_A);
al &= 0x0f;
}
EAX = (EAX & ~0xffff) | al | (ah << 8);
CC_SRC = eflags;
}
void helper_daa(CPUX86State *env)
{
int al, af, cf;
int eflags;
eflags = helper_cc_compute_all(env, CC_OP);
cf = eflags & CC_C;
af = eflags & CC_A;
al = EAX & 0xff;
eflags = 0;
if (((al & 0x0f) > 9 ) || af) {
al = (al + 6) & 0xff;
eflags |= CC_A;
}
if ((al > 0x9f) || cf) {
al = (al + 0x60) & 0xff;
eflags |= CC_C;
}
EAX = (EAX & ~0xff) | al;
/* well, speed is not an issue here, so we compute the flags by hand */
eflags |= (al == 0) << 6; /* zf */
eflags |= parity_table[al]; /* pf */
eflags |= (al & 0x80); /* sf */
CC_SRC = eflags;
}
void helper_das(CPUX86State *env)
{
int al, al1, af, cf;
int eflags;
eflags = helper_cc_compute_all(env, CC_OP);
cf = eflags & CC_C;
af = eflags & CC_A;
al = EAX & 0xff;
eflags = 0;
al1 = al;
if (((al & 0x0f) > 9 ) || af) {
eflags |= CC_A;
if (al < 6 || cf)
eflags |= CC_C;
al = (al - 6) & 0xff;
}
if ((al1 > 0x99) || cf) {
al = (al - 0x60) & 0xff;
eflags |= CC_C;
}
EAX = (EAX & ~0xff) | al;
/* well, speed is not an issue here, so we compute the flags by hand */
eflags |= (al == 0) << 6; /* zf */
eflags |= parity_table[al]; /* pf */
eflags |= (al & 0x80); /* sf */
CC_SRC = eflags;
}
#ifdef TARGET_X86_64
static void add128(uint64_t *plow, uint64_t *phigh, uint64_t a, uint64_t b)
{
*plow += a;
/* carry test */
if (*plow < a)
(*phigh)++;
*phigh += b;
}
static void neg128(uint64_t *plow, uint64_t *phigh)
{
*plow = ~ *plow;
*phigh = ~ *phigh;
add128(plow, phigh, 1, 0);
}
/* return TRUE if overflow */
static int div64(uint64_t *plow, uint64_t *phigh, uint64_t b)
{
uint64_t q, r, a1, a0;
int i, qb, ab;
a0 = *plow;
a1 = *phigh;
if (a1 == 0) {
q = a0 / b;
r = a0 % b;
*plow = q;
*phigh = r;
} else {
if (a1 >= b)
return 1;
/* XXX: use a better algorithm */
for(i = 0; i < 64; i++) {
ab = a1 >> 63;
a1 = (a1 << 1) | (a0 >> 63);
if (ab || a1 >= b) {
a1 -= b;
qb = 1;
} else {
qb = 0;
}
a0 = (a0 << 1) | qb;
}
#if defined(DEBUG_MULDIV)
printf("div: 0x%016" PRIx64 "%016" PRIx64 " / 0x%016" PRIx64 ": q=0x%016" PRIx64 " r=0x%016" PRIx64 "\n",
*phigh, *plow, b, a0, a1);
#endif
*plow = a0;
*phigh = a1;
}
return 0;
}
/* return TRUE if overflow */
static int idiv64(uint64_t *plow, uint64_t *phigh, int64_t b)
{
int sa, sb;
sa = ((int64_t)*phigh < 0);
if (sa)
neg128(plow, phigh);
sb = (b < 0);
if (sb)
b = -b;
if (div64(plow, phigh, b) != 0)
return 1;
if (sa ^ sb) {
if (*plow > (1ULL << 63))
return 1;
*plow = - *plow;
} else {
if (*plow >= (1ULL << 63))
return 1;
}
if (sa)
*phigh = - *phigh;
return 0;
}
void helper_mulq_EAX_T0(CPUX86State *env, target_ulong t0)
{
uint64_t r0, r1;
mulu64(&r0, &r1, EAX, t0);
EAX = r0;
EDX = r1;
CC_DST = r0;
CC_SRC = r1;
}
void helper_imulq_EAX_T0(CPUX86State *env, target_ulong t0)
{
uint64_t r0, r1;
muls64(&r0, &r1, EAX, t0);
EAX = r0;
EDX = r1;
CC_DST = r0;
CC_SRC = ((int64_t)r1 != ((int64_t)r0 >> 63));
}
target_ulong helper_imulq_T0_T1(CPUX86State *env, target_ulong t0, target_ulong t1)
{
uint64_t r0, r1;
muls64(&r0, &r1, t0, t1);
CC_DST = r0;
CC_SRC = ((int64_t)r1 != ((int64_t)r0 >> 63));
return r0;
}
void helper_divq_EAX(CPUX86State *env, target_ulong t0)
{
uint64_t r0, r1;
if (t0 == 0) {
raise_exception(env, EXCP00_DIVZ);
}
r0 = EAX;
r1 = EDX;
if (div64(&r0, &r1, t0))
raise_exception(env, EXCP00_DIVZ);
EAX = r0;
EDX = r1;
}
void helper_idivq_EAX(CPUX86State *env, target_ulong t0)
{
uint64_t r0, r1;
if (t0 == 0) {
raise_exception(env, EXCP00_DIVZ);
}
r0 = EAX;
r1 = EDX;
if (idiv64(&r0, &r1, t0))
raise_exception(env, EXCP00_DIVZ);
EAX = r0;
EDX = r1;
}
#endif
#define SHIFT 0
#include "shift_helper_template.h"
#undef SHIFT
#define SHIFT 1
#include "shift_helper_template.h"
#undef SHIFT
#define SHIFT 2
#include "shift_helper_template.h"
#undef SHIFT
#ifdef TARGET_X86_64
#define SHIFT 3
#include "shift_helper_template.h"
#undef SHIFT
#endif
/* bit operations */
target_ulong helper_bsf(target_ulong t0)
{
int count;
target_ulong res;
res = t0;
count = 0;
while ((res & 1) == 0) {
count++;
res >>= 1;
}
return count;
}
target_ulong helper_bsr(target_ulong t0)
{
int count;
target_ulong res, mask;
res = t0;
count = TARGET_LONG_BITS - 1;
mask = (target_ulong)1 << (TARGET_LONG_BITS - 1);
while ((res & mask) == 0) {
count--;
res <<= 1;
}
return count;
}