qemu/helper-i386.c
bellard 3ec9c4fcc6 separated helpers from micro operations
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@204 c046a42c-6fe2-441c-8c8c-71466251a162
2003-06-05 00:54:09 +00:00

736 lines
18 KiB
C

/*
* i386 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, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "exec-i386.h"
#if 0
/* full interrupt support (only useful for real CPU emulation, not
finished) - I won't do it any time soon, finish it if you want ! */
void raise_interrupt(int intno, int is_int, int error_code,
unsigned int next_eip)
{
SegmentDescriptorTable *dt;
uint8_t *ptr;
int type, dpl, cpl;
uint32_t e1, e2;
dt = &env->idt;
if (intno * 8 + 7 > dt->limit)
raise_exception_err(EXCP0D_GPF, intno * 8 + 2);
ptr = dt->base + intno * 8;
e1 = ldl(ptr);
e2 = ldl(ptr + 4);
/* check gate type */
type = (e2 >> DESC_TYPE_SHIFT) & 0x1f;
switch(type) {
case 5: /* task gate */
case 6: /* 286 interrupt gate */
case 7: /* 286 trap gate */
case 14: /* 386 interrupt gate */
case 15: /* 386 trap gate */
break;
default:
raise_exception_err(EXCP0D_GPF, intno * 8 + 2);
break;
}
dpl = (e2 >> DESC_DPL_SHIFT) & 3;
cpl = env->segs[R_CS] & 3;
/* check privledge if software int */
if (is_int && dpl < cpl)
raise_exception_err(EXCP0D_GPF, intno * 8 + 2);
/* check valid bit */
if (!(e2 & DESC_P_MASK))
raise_exception_err(EXCP0B_NOSEG, intno * 8 + 2);
}
#else
/*
* is_int is TRUE if coming from the int instruction. next_eip is the
* EIP value AFTER the interrupt instruction. It is only relevant if
* is_int is TRUE.
*/
void raise_interrupt(int intno, int is_int, int error_code,
unsigned int next_eip)
{
SegmentDescriptorTable *dt;
uint8_t *ptr;
int dpl, cpl;
uint32_t e2;
dt = &env->idt;
ptr = dt->base + (intno * 8);
e2 = ldl(ptr + 4);
dpl = (e2 >> DESC_DPL_SHIFT) & 3;
cpl = 3;
/* check privledge if software int */
if (is_int && dpl < cpl)
raise_exception_err(EXCP0D_GPF, intno * 8 + 2);
/* Since we emulate only user space, we cannot do more than
exiting the emulation with the suitable exception and error
code */
if (is_int)
EIP = next_eip;
env->exception_index = intno;
env->error_code = error_code;
cpu_loop_exit();
}
#endif
/* shortcuts to generate exceptions */
void raise_exception_err(int exception_index, int error_code)
{
raise_interrupt(exception_index, 0, error_code, 0);
}
void raise_exception(int exception_index)
{
raise_interrupt(exception_index, 0, 0, 0);
}
/* We simulate a pre-MMX pentium as in valgrind */
#define CPUID_FP87 (1 << 0)
#define CPUID_VME (1 << 1)
#define CPUID_DE (1 << 2)
#define CPUID_PSE (1 << 3)
#define CPUID_TSC (1 << 4)
#define CPUID_MSR (1 << 5)
#define CPUID_PAE (1 << 6)
#define CPUID_MCE (1 << 7)
#define CPUID_CX8 (1 << 8)
#define CPUID_APIC (1 << 9)
#define CPUID_SEP (1 << 11) /* sysenter/sysexit */
#define CPUID_MTRR (1 << 12)
#define CPUID_PGE (1 << 13)
#define CPUID_MCA (1 << 14)
#define CPUID_CMOV (1 << 15)
/* ... */
#define CPUID_MMX (1 << 23)
#define CPUID_FXSR (1 << 24)
#define CPUID_SSE (1 << 25)
#define CPUID_SSE2 (1 << 26)
void helper_cpuid(void)
{
if (EAX == 0) {
EAX = 1; /* max EAX index supported */
EBX = 0x756e6547;
ECX = 0x6c65746e;
EDX = 0x49656e69;
} else if (EAX == 1) {
/* EAX = 1 info */
EAX = 0x52b;
EBX = 0;
ECX = 0;
EDX = CPUID_FP87 | CPUID_DE | CPUID_PSE |
CPUID_TSC | CPUID_MSR | CPUID_MCE |
CPUID_CX8;
}
}
/* only works if protected mode and not VM86 */
void load_seg(int seg_reg, int selector, unsigned cur_eip)
{
SegmentCache *sc;
SegmentDescriptorTable *dt;
int index;
uint32_t e1, e2;
uint8_t *ptr;
sc = &env->seg_cache[seg_reg];
if ((selector & 0xfffc) == 0) {
/* null selector case */
if (seg_reg == R_SS) {
EIP = cur_eip;
raise_exception_err(EXCP0D_GPF, selector & 0xfffc);
} else {
/* XXX: each access should trigger an exception */
sc->base = NULL;
sc->limit = 0;
sc->seg_32bit = 1;
}
} else {
if (selector & 0x4)
dt = &env->ldt;
else
dt = &env->gdt;
index = selector & ~7;
if ((index + 7) > dt->limit) {
EIP = cur_eip;
raise_exception_err(EXCP0D_GPF, selector & 0xfffc);
}
ptr = dt->base + index;
e1 = ldl(ptr);
e2 = ldl(ptr + 4);
if (!(e2 & DESC_S_MASK) ||
(e2 & (DESC_CS_MASK | DESC_R_MASK)) == DESC_CS_MASK) {
EIP = cur_eip;
raise_exception_err(EXCP0D_GPF, selector & 0xfffc);
}
if (seg_reg == R_SS) {
if ((e2 & (DESC_CS_MASK | DESC_W_MASK)) == 0) {
EIP = cur_eip;
raise_exception_err(EXCP0D_GPF, selector & 0xfffc);
}
} else {
if ((e2 & (DESC_CS_MASK | DESC_R_MASK)) == DESC_CS_MASK) {
EIP = cur_eip;
raise_exception_err(EXCP0D_GPF, selector & 0xfffc);
}
}
if (!(e2 & DESC_P_MASK)) {
EIP = cur_eip;
if (seg_reg == R_SS)
raise_exception_err(EXCP0C_STACK, selector & 0xfffc);
else
raise_exception_err(EXCP0B_NOSEG, selector & 0xfffc);
}
sc->base = (void *)((e1 >> 16) | ((e2 & 0xff) << 16) | (e2 & 0xff000000));
sc->limit = (e1 & 0xffff) | (e2 & 0x000f0000);
if (e2 & (1 << 23))
sc->limit = (sc->limit << 12) | 0xfff;
sc->seg_32bit = (e2 >> 22) & 1;
#if 0
fprintf(logfile, "load_seg: sel=0x%04x base=0x%08lx limit=0x%08lx seg_32bit=%d\n",
selector, (unsigned long)sc->base, sc->limit, sc->seg_32bit);
#endif
}
env->segs[seg_reg] = selector;
}
void helper_lsl(void)
{
unsigned int selector, limit;
SegmentDescriptorTable *dt;
int index;
uint32_t e1, e2;
uint8_t *ptr;
CC_SRC = cc_table[CC_OP].compute_all() & ~CC_Z;
selector = T0 & 0xffff;
if (selector & 0x4)
dt = &env->ldt;
else
dt = &env->gdt;
index = selector & ~7;
if ((index + 7) > dt->limit)
return;
ptr = dt->base + index;
e1 = ldl(ptr);
e2 = ldl(ptr + 4);
limit = (e1 & 0xffff) | (e2 & 0x000f0000);
if (e2 & (1 << 23))
limit = (limit << 12) | 0xfff;
T1 = limit;
CC_SRC |= CC_Z;
}
void helper_lar(void)
{
unsigned int selector;
SegmentDescriptorTable *dt;
int index;
uint32_t e2;
uint8_t *ptr;
CC_SRC = cc_table[CC_OP].compute_all() & ~CC_Z;
selector = T0 & 0xffff;
if (selector & 0x4)
dt = &env->ldt;
else
dt = &env->gdt;
index = selector & ~7;
if ((index + 7) > dt->limit)
return;
ptr = dt->base + index;
e2 = ldl(ptr + 4);
T1 = e2 & 0x00f0ff00;
CC_SRC |= CC_Z;
}
/* FPU helpers */
#ifndef USE_X86LDOUBLE
void helper_fldt_ST0_A0(void)
{
ST0 = helper_fldt((uint8_t *)A0);
}
void helper_fstt_ST0_A0(void)
{
helper_fstt(ST0, (uint8_t *)A0);
}
#endif
/* BCD ops */
#define MUL10(iv) ( iv + iv + (iv << 3) )
void helper_fbld_ST0_A0(void)
{
uint8_t *seg;
CPU86_LDouble fpsrcop;
int m32i;
unsigned int v;
/* in this code, seg/m32i will be used as temporary ptr/int */
seg = (uint8_t *)A0 + 8;
v = ldub(seg--);
/* XXX: raise exception */
if (v != 0)
return;
v = ldub(seg--);
/* XXX: raise exception */
if ((v & 0xf0) != 0)
return;
m32i = v; /* <-- d14 */
v = ldub(seg--);
m32i = MUL10(m32i) + (v >> 4); /* <-- val * 10 + d13 */
m32i = MUL10(m32i) + (v & 0xf); /* <-- val * 10 + d12 */
v = ldub(seg--);
m32i = MUL10(m32i) + (v >> 4); /* <-- val * 10 + d11 */
m32i = MUL10(m32i) + (v & 0xf); /* <-- val * 10 + d10 */
v = ldub(seg--);
m32i = MUL10(m32i) + (v >> 4); /* <-- val * 10 + d9 */
m32i = MUL10(m32i) + (v & 0xf); /* <-- val * 10 + d8 */
fpsrcop = ((CPU86_LDouble)m32i) * 100000000.0;
v = ldub(seg--);
m32i = (v >> 4); /* <-- d7 */
m32i = MUL10(m32i) + (v & 0xf); /* <-- val * 10 + d6 */
v = ldub(seg--);
m32i = MUL10(m32i) + (v >> 4); /* <-- val * 10 + d5 */
m32i = MUL10(m32i) + (v & 0xf); /* <-- val * 10 + d4 */
v = ldub(seg--);
m32i = MUL10(m32i) + (v >> 4); /* <-- val * 10 + d3 */
m32i = MUL10(m32i) + (v & 0xf); /* <-- val * 10 + d2 */
v = ldub(seg);
m32i = MUL10(m32i) + (v >> 4); /* <-- val * 10 + d1 */
m32i = MUL10(m32i) + (v & 0xf); /* <-- val * 10 + d0 */
fpsrcop += ((CPU86_LDouble)m32i);
if ( ldub(seg+9) & 0x80 )
fpsrcop = -fpsrcop;
ST0 = fpsrcop;
}
void helper_fbst_ST0_A0(void)
{
CPU86_LDouble fptemp;
CPU86_LDouble fpsrcop;
int v;
uint8_t *mem_ref, *mem_end;
fpsrcop = rint(ST0);
mem_ref = (uint8_t *)A0;
mem_end = mem_ref + 8;
if ( fpsrcop < 0.0 ) {
stw(mem_end, 0x8000);
fpsrcop = -fpsrcop;
} else {
stw(mem_end, 0x0000);
}
while (mem_ref < mem_end) {
if (fpsrcop == 0.0)
break;
fptemp = floor(fpsrcop/10.0);
v = ((int)(fpsrcop - fptemp*10.0));
if (fptemp == 0.0) {
stb(mem_ref++, v);
break;
}
fpsrcop = fptemp;
fptemp = floor(fpsrcop/10.0);
v |= (((int)(fpsrcop - fptemp*10.0)) << 4);
stb(mem_ref++, v);
fpsrcop = fptemp;
}
while (mem_ref < mem_end) {
stb(mem_ref++, 0);
}
}
void helper_f2xm1(void)
{
ST0 = pow(2.0,ST0) - 1.0;
}
void helper_fyl2x(void)
{
CPU86_LDouble fptemp;
fptemp = ST0;
if (fptemp>0.0){
fptemp = log(fptemp)/log(2.0); /* log2(ST) */
ST1 *= fptemp;
fpop();
} else {
env->fpus &= (~0x4700);
env->fpus |= 0x400;
}
}
void helper_fptan(void)
{
CPU86_LDouble fptemp;
fptemp = ST0;
if((fptemp > MAXTAN)||(fptemp < -MAXTAN)) {
env->fpus |= 0x400;
} else {
ST0 = tan(fptemp);
fpush();
ST0 = 1.0;
env->fpus &= (~0x400); /* C2 <-- 0 */
/* the above code is for |arg| < 2**52 only */
}
}
void helper_fpatan(void)
{
CPU86_LDouble fptemp, fpsrcop;
fpsrcop = ST1;
fptemp = ST0;
ST1 = atan2(fpsrcop,fptemp);
fpop();
}
void helper_fxtract(void)
{
CPU86_LDoubleU temp;
unsigned int expdif;
temp.d = ST0;
expdif = EXPD(temp) - EXPBIAS;
/*DP exponent bias*/
ST0 = expdif;
fpush();
BIASEXPONENT(temp);
ST0 = temp.d;
}
void helper_fprem1(void)
{
CPU86_LDouble dblq, fpsrcop, fptemp;
CPU86_LDoubleU fpsrcop1, fptemp1;
int expdif;
int q;
fpsrcop = ST0;
fptemp = ST1;
fpsrcop1.d = fpsrcop;
fptemp1.d = fptemp;
expdif = EXPD(fpsrcop1) - EXPD(fptemp1);
if (expdif < 53) {
dblq = fpsrcop / fptemp;
dblq = (dblq < 0.0)? ceil(dblq): floor(dblq);
ST0 = fpsrcop - fptemp*dblq;
q = (int)dblq; /* cutting off top bits is assumed here */
env->fpus &= (~0x4700); /* (C3,C2,C1,C0) <-- 0000 */
/* (C0,C1,C3) <-- (q2,q1,q0) */
env->fpus |= (q&0x4) << 6; /* (C0) <-- q2 */
env->fpus |= (q&0x2) << 8; /* (C1) <-- q1 */
env->fpus |= (q&0x1) << 14; /* (C3) <-- q0 */
} else {
env->fpus |= 0x400; /* C2 <-- 1 */
fptemp = pow(2.0, expdif-50);
fpsrcop = (ST0 / ST1) / fptemp;
/* fpsrcop = integer obtained by rounding to the nearest */
fpsrcop = (fpsrcop-floor(fpsrcop) < ceil(fpsrcop)-fpsrcop)?
floor(fpsrcop): ceil(fpsrcop);
ST0 -= (ST1 * fpsrcop * fptemp);
}
}
void helper_fprem(void)
{
CPU86_LDouble dblq, fpsrcop, fptemp;
CPU86_LDoubleU fpsrcop1, fptemp1;
int expdif;
int q;
fpsrcop = ST0;
fptemp = ST1;
fpsrcop1.d = fpsrcop;
fptemp1.d = fptemp;
expdif = EXPD(fpsrcop1) - EXPD(fptemp1);
if ( expdif < 53 ) {
dblq = fpsrcop / fptemp;
dblq = (dblq < 0.0)? ceil(dblq): floor(dblq);
ST0 = fpsrcop - fptemp*dblq;
q = (int)dblq; /* cutting off top bits is assumed here */
env->fpus &= (~0x4700); /* (C3,C2,C1,C0) <-- 0000 */
/* (C0,C1,C3) <-- (q2,q1,q0) */
env->fpus |= (q&0x4) << 6; /* (C0) <-- q2 */
env->fpus |= (q&0x2) << 8; /* (C1) <-- q1 */
env->fpus |= (q&0x1) << 14; /* (C3) <-- q0 */
} else {
env->fpus |= 0x400; /* C2 <-- 1 */
fptemp = pow(2.0, expdif-50);
fpsrcop = (ST0 / ST1) / fptemp;
/* fpsrcop = integer obtained by chopping */
fpsrcop = (fpsrcop < 0.0)?
-(floor(fabs(fpsrcop))): floor(fpsrcop);
ST0 -= (ST1 * fpsrcop * fptemp);
}
}
void helper_fyl2xp1(void)
{
CPU86_LDouble fptemp;
fptemp = ST0;
if ((fptemp+1.0)>0.0) {
fptemp = log(fptemp+1.0) / log(2.0); /* log2(ST+1.0) */
ST1 *= fptemp;
fpop();
} else {
env->fpus &= (~0x4700);
env->fpus |= 0x400;
}
}
void helper_fsqrt(void)
{
CPU86_LDouble fptemp;
fptemp = ST0;
if (fptemp<0.0) {
env->fpus &= (~0x4700); /* (C3,C2,C1,C0) <-- 0000 */
env->fpus |= 0x400;
}
ST0 = sqrt(fptemp);
}
void helper_fsincos(void)
{
CPU86_LDouble fptemp;
fptemp = ST0;
if ((fptemp > MAXTAN)||(fptemp < -MAXTAN)) {
env->fpus |= 0x400;
} else {
ST0 = sin(fptemp);
fpush();
ST0 = cos(fptemp);
env->fpus &= (~0x400); /* C2 <-- 0 */
/* the above code is for |arg| < 2**63 only */
}
}
void helper_frndint(void)
{
ST0 = rint(ST0);
}
void helper_fscale(void)
{
CPU86_LDouble fpsrcop, fptemp;
fpsrcop = 2.0;
fptemp = pow(fpsrcop,ST1);
ST0 *= fptemp;
}
void helper_fsin(void)
{
CPU86_LDouble fptemp;
fptemp = ST0;
if ((fptemp > MAXTAN)||(fptemp < -MAXTAN)) {
env->fpus |= 0x400;
} else {
ST0 = sin(fptemp);
env->fpus &= (~0x400); /* C2 <-- 0 */
/* the above code is for |arg| < 2**53 only */
}
}
void helper_fcos(void)
{
CPU86_LDouble fptemp;
fptemp = ST0;
if((fptemp > MAXTAN)||(fptemp < -MAXTAN)) {
env->fpus |= 0x400;
} else {
ST0 = cos(fptemp);
env->fpus &= (~0x400); /* C2 <-- 0 */
/* the above code is for |arg5 < 2**63 only */
}
}
void helper_fxam_ST0(void)
{
CPU86_LDoubleU temp;
int expdif;
temp.d = ST0;
env->fpus &= (~0x4700); /* (C3,C2,C1,C0) <-- 0000 */
if (SIGND(temp))
env->fpus |= 0x200; /* C1 <-- 1 */
expdif = EXPD(temp);
if (expdif == MAXEXPD) {
if (MANTD(temp) == 0)
env->fpus |= 0x500 /*Infinity*/;
else
env->fpus |= 0x100 /*NaN*/;
} else if (expdif == 0) {
if (MANTD(temp) == 0)
env->fpus |= 0x4000 /*Zero*/;
else
env->fpus |= 0x4400 /*Denormal*/;
} else {
env->fpus |= 0x400;
}
}
void helper_fstenv(uint8_t *ptr, int data32)
{
int fpus, fptag, exp, i;
uint64_t mant;
CPU86_LDoubleU tmp;
fpus = (env->fpus & ~0x3800) | (env->fpstt & 0x7) << 11;
fptag = 0;
for (i=7; i>=0; i--) {
fptag <<= 2;
if (env->fptags[i]) {
fptag |= 3;
} else {
tmp.d = env->fpregs[i];
exp = EXPD(tmp);
mant = MANTD(tmp);
if (exp == 0 && mant == 0) {
/* zero */
fptag |= 1;
} else if (exp == 0 || exp == MAXEXPD
#ifdef USE_X86LDOUBLE
|| (mant & (1LL << 63)) == 0
#endif
) {
/* NaNs, infinity, denormal */
fptag |= 2;
}
}
}
if (data32) {
/* 32 bit */
stl(ptr, env->fpuc);
stl(ptr + 4, fpus);
stl(ptr + 8, fptag);
stl(ptr + 12, 0);
stl(ptr + 16, 0);
stl(ptr + 20, 0);
stl(ptr + 24, 0);
} else {
/* 16 bit */
stw(ptr, env->fpuc);
stw(ptr + 2, fpus);
stw(ptr + 4, fptag);
stw(ptr + 6, 0);
stw(ptr + 8, 0);
stw(ptr + 10, 0);
stw(ptr + 12, 0);
}
}
void helper_fldenv(uint8_t *ptr, int data32)
{
int i, fpus, fptag;
if (data32) {
env->fpuc = lduw(ptr);
fpus = lduw(ptr + 4);
fptag = lduw(ptr + 8);
}
else {
env->fpuc = lduw(ptr);
fpus = lduw(ptr + 2);
fptag = lduw(ptr + 4);
}
env->fpstt = (fpus >> 11) & 7;
env->fpus = fpus & ~0x3800;
for(i = 0;i < 7; i++) {
env->fptags[i] = ((fptag & 3) == 3);
fptag >>= 2;
}
}
void helper_fsave(uint8_t *ptr, int data32)
{
CPU86_LDouble tmp;
int i;
helper_fstenv(ptr, data32);
ptr += (14 << data32);
for(i = 0;i < 8; i++) {
tmp = ST(i);
#ifdef USE_X86LDOUBLE
*(long double *)ptr = tmp;
#else
helper_fstt(tmp, ptr);
#endif
ptr += 10;
}
/* fninit */
env->fpus = 0;
env->fpstt = 0;
env->fpuc = 0x37f;
env->fptags[0] = 1;
env->fptags[1] = 1;
env->fptags[2] = 1;
env->fptags[3] = 1;
env->fptags[4] = 1;
env->fptags[5] = 1;
env->fptags[6] = 1;
env->fptags[7] = 1;
}
void helper_frstor(uint8_t *ptr, int data32)
{
CPU86_LDouble tmp;
int i;
helper_fldenv(ptr, data32);
ptr += (14 << data32);
for(i = 0;i < 8; i++) {
#ifdef USE_X86LDOUBLE
tmp = *(long double *)ptr;
#else
tmp = helper_fldt(ptr);
#endif
ST(i) = tmp;
ptr += 10;
}
}