qemu/target/i386/int_helper.c
Chetan Pant d9ff33ada7 x86 tcg cpus: Fix Lesser GPL version number
There is no "version 2" of the "Lesser" General Public License.
It is either "GPL version 2.0" or "Lesser GPL version 2.1".
This patch replaces all occurrences of "Lesser GPL version 2" with
"Lesser GPL version 2.1" in comment section.

Signed-off-by: Chetan Pant <chetan4windows@gmail.com>
Message-Id: <20201023122801.19514-1-chetan4windows@gmail.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-11-15 16:41:42 +01:00

494 lines
12 KiB
C

/*
* 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 2.1 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 "qemu/osdep.h"
#include "cpu.h"
#include "exec/exec-all.h"
#include "qemu/host-utils.h"
#include "exec/helper-proto.h"
#include "qapi/error.h"
#include "qemu/guest-random.h"
//#define DEBUG_MULDIV
/* 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,
};
/* 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,
};
/* division, flags are undefined */
void helper_divb_AL(CPUX86State *env, target_ulong t0)
{
unsigned int num, den, q, r;
num = (env->regs[R_EAX] & 0xffff);
den = (t0 & 0xff);
if (den == 0) {
raise_exception_ra(env, EXCP00_DIVZ, GETPC());
}
q = (num / den);
if (q > 0xff) {
raise_exception_ra(env, EXCP00_DIVZ, GETPC());
}
q &= 0xff;
r = (num % den) & 0xff;
env->regs[R_EAX] = (env->regs[R_EAX] & ~0xffff) | (r << 8) | q;
}
void helper_idivb_AL(CPUX86State *env, target_ulong t0)
{
int num, den, q, r;
num = (int16_t)env->regs[R_EAX];
den = (int8_t)t0;
if (den == 0) {
raise_exception_ra(env, EXCP00_DIVZ, GETPC());
}
q = (num / den);
if (q != (int8_t)q) {
raise_exception_ra(env, EXCP00_DIVZ, GETPC());
}
q &= 0xff;
r = (num % den) & 0xff;
env->regs[R_EAX] = (env->regs[R_EAX] & ~0xffff) | (r << 8) | q;
}
void helper_divw_AX(CPUX86State *env, target_ulong t0)
{
unsigned int num, den, q, r;
num = (env->regs[R_EAX] & 0xffff) | ((env->regs[R_EDX] & 0xffff) << 16);
den = (t0 & 0xffff);
if (den == 0) {
raise_exception_ra(env, EXCP00_DIVZ, GETPC());
}
q = (num / den);
if (q > 0xffff) {
raise_exception_ra(env, EXCP00_DIVZ, GETPC());
}
q &= 0xffff;
r = (num % den) & 0xffff;
env->regs[R_EAX] = (env->regs[R_EAX] & ~0xffff) | q;
env->regs[R_EDX] = (env->regs[R_EDX] & ~0xffff) | r;
}
void helper_idivw_AX(CPUX86State *env, target_ulong t0)
{
int num, den, q, r;
num = (env->regs[R_EAX] & 0xffff) | ((env->regs[R_EDX] & 0xffff) << 16);
den = (int16_t)t0;
if (den == 0) {
raise_exception_ra(env, EXCP00_DIVZ, GETPC());
}
q = (num / den);
if (q != (int16_t)q) {
raise_exception_ra(env, EXCP00_DIVZ, GETPC());
}
q &= 0xffff;
r = (num % den) & 0xffff;
env->regs[R_EAX] = (env->regs[R_EAX] & ~0xffff) | q;
env->regs[R_EDX] = (env->regs[R_EDX] & ~0xffff) | r;
}
void helper_divl_EAX(CPUX86State *env, target_ulong t0)
{
unsigned int den, r;
uint64_t num, q;
num = ((uint32_t)env->regs[R_EAX]) | ((uint64_t)((uint32_t)env->regs[R_EDX]) << 32);
den = t0;
if (den == 0) {
raise_exception_ra(env, EXCP00_DIVZ, GETPC());
}
q = (num / den);
r = (num % den);
if (q > 0xffffffff) {
raise_exception_ra(env, EXCP00_DIVZ, GETPC());
}
env->regs[R_EAX] = (uint32_t)q;
env->regs[R_EDX] = (uint32_t)r;
}
void helper_idivl_EAX(CPUX86State *env, target_ulong t0)
{
int den, r;
int64_t num, q;
num = ((uint32_t)env->regs[R_EAX]) | ((uint64_t)((uint32_t)env->regs[R_EDX]) << 32);
den = t0;
if (den == 0) {
raise_exception_ra(env, EXCP00_DIVZ, GETPC());
}
q = (num / den);
r = (num % den);
if (q != (int32_t)q) {
raise_exception_ra(env, EXCP00_DIVZ, GETPC());
}
env->regs[R_EAX] = (uint32_t)q;
env->regs[R_EDX] = (uint32_t)r;
}
/* bcd */
/* XXX: exception */
void helper_aam(CPUX86State *env, int base)
{
int al, ah;
al = env->regs[R_EAX] & 0xff;
ah = al / base;
al = al % base;
env->regs[R_EAX] = (env->regs[R_EAX] & ~0xffff) | al | (ah << 8);
CC_DST = al;
}
void helper_aad(CPUX86State *env, int base)
{
int al, ah;
al = env->regs[R_EAX] & 0xff;
ah = (env->regs[R_EAX] >> 8) & 0xff;
al = ((ah * base) + al) & 0xff;
env->regs[R_EAX] = (env->regs[R_EAX] & ~0xffff) | al;
CC_DST = al;
}
void helper_aaa(CPUX86State *env)
{
int icarry;
int al, ah, af;
int eflags;
eflags = cpu_cc_compute_all(env, CC_OP);
af = eflags & CC_A;
al = env->regs[R_EAX] & 0xff;
ah = (env->regs[R_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;
}
env->regs[R_EAX] = (env->regs[R_EAX] & ~0xffff) | al | (ah << 8);
CC_SRC = eflags;
}
void helper_aas(CPUX86State *env)
{
int icarry;
int al, ah, af;
int eflags;
eflags = cpu_cc_compute_all(env, CC_OP);
af = eflags & CC_A;
al = env->regs[R_EAX] & 0xff;
ah = (env->regs[R_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;
}
env->regs[R_EAX] = (env->regs[R_EAX] & ~0xffff) | al | (ah << 8);
CC_SRC = eflags;
}
void helper_daa(CPUX86State *env)
{
int old_al, al, af, cf;
int eflags;
eflags = cpu_cc_compute_all(env, CC_OP);
cf = eflags & CC_C;
af = eflags & CC_A;
old_al = al = env->regs[R_EAX] & 0xff;
eflags = 0;
if (((al & 0x0f) > 9) || af) {
al = (al + 6) & 0xff;
eflags |= CC_A;
}
if ((old_al > 0x99) || cf) {
al = (al + 0x60) & 0xff;
eflags |= CC_C;
}
env->regs[R_EAX] = (env->regs[R_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 = cpu_cc_compute_all(env, CC_OP);
cf = eflags & CC_C;
af = eflags & CC_A;
al = env->regs[R_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;
}
env->regs[R_EAX] = (env->regs[R_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_divq_EAX(CPUX86State *env, target_ulong t0)
{
uint64_t r0, r1;
if (t0 == 0) {
raise_exception_ra(env, EXCP00_DIVZ, GETPC());
}
r0 = env->regs[R_EAX];
r1 = env->regs[R_EDX];
if (div64(&r0, &r1, t0)) {
raise_exception_ra(env, EXCP00_DIVZ, GETPC());
}
env->regs[R_EAX] = r0;
env->regs[R_EDX] = r1;
}
void helper_idivq_EAX(CPUX86State *env, target_ulong t0)
{
uint64_t r0, r1;
if (t0 == 0) {
raise_exception_ra(env, EXCP00_DIVZ, GETPC());
}
r0 = env->regs[R_EAX];
r1 = env->regs[R_EDX];
if (idiv64(&r0, &r1, t0)) {
raise_exception_ra(env, EXCP00_DIVZ, GETPC());
}
env->regs[R_EAX] = r0;
env->regs[R_EDX] = r1;
}
#endif
#if TARGET_LONG_BITS == 32
# define ctztl ctz32
# define clztl clz32
#else
# define ctztl ctz64
# define clztl clz64
#endif
target_ulong helper_pdep(target_ulong src, target_ulong mask)
{
target_ulong dest = 0;
int i, o;
for (i = 0; mask != 0; i++) {
o = ctztl(mask);
mask &= mask - 1;
dest |= ((src >> i) & 1) << o;
}
return dest;
}
target_ulong helper_pext(target_ulong src, target_ulong mask)
{
target_ulong dest = 0;
int i, o;
for (o = 0; mask != 0; o++) {
i = ctztl(mask);
mask &= mask - 1;
dest |= ((src >> i) & 1) << o;
}
return dest;
}
#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
/* Test that BIT is enabled in CR4. If not, raise an illegal opcode
exception. This reduces the requirements for rare CR4 bits being
mapped into HFLAGS. */
void helper_cr4_testbit(CPUX86State *env, uint32_t bit)
{
if (unlikely((env->cr[4] & bit) == 0)) {
raise_exception_ra(env, EXCP06_ILLOP, GETPC());
}
}
target_ulong HELPER(rdrand)(CPUX86State *env)
{
Error *err = NULL;
target_ulong ret;
if (qemu_guest_getrandom(&ret, sizeof(ret), &err) < 0) {
qemu_log_mask(LOG_UNIMP, "rdrand: Crypto failure: %s",
error_get_pretty(err));
error_free(err);
/* Failure clears CF and all other flags, and returns 0. */
env->cc_src = 0;
return 0;
}
/* Success sets CF and clears all others. */
env->cc_src = CC_C;
return ret;
}