Bochs/bochs/cpu/ctrl_xfer16.cc
Kevin Lawton a17d06abcb Optimized the main cpu loop iCache checks to remove a redundant
check.

Commented out a number of instances of invalidate_prefetch_q(),
for branches which do not change CS since the EIP window mechanism
takes care of validating that EIP lands in the current page or not
in the main cpu loop anyways.

Fixed a couple cases (v8086 mode and real mode) of loading CS where
the EIP page window was not invalidated in segment_ctrl_pro.cc.
That may fix some aliasing problems reported before (OS2).
2003-05-10 22:25:55 +00:00

540 lines
12 KiB
C++

/////////////////////////////////////////////////////////////////////////
// $Id: ctrl_xfer16.cc,v 1.20 2003-05-10 22:25:51 kevinlawton Exp $
/////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 2001 MandrakeSoft S.A.
//
// MandrakeSoft S.A.
// 43, rue d'Aboukir
// 75002 Paris - France
// http://www.linux-mandrake.com/
// http://www.mandrakesoft.com/
//
// 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
#define NEED_CPU_REG_SHORTCUTS 1
#include "bochs.h"
#define LOG_THIS BX_CPU_THIS_PTR
void
BX_CPU_C::RETnear16_Iw(bxInstruction_c *i)
{
BailBigRSP("RETnear16_Iw");
Bit16u imm16;
Bit16u return_IP;
//invalidate_prefetch_q();
#if BX_DEBUGGER
BX_CPU_THIS_PTR show_flag |= Flag_ret;
#endif
imm16 = i->Iw();
pop_16(&return_IP);
if (protected_mode()) {
if ( return_IP >
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled ) {
BX_PANIC(("retnear_iw: IP > limit"));
}
}
EIP = return_IP;
if (BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache.u.segment.d_b) /* 32bit stack */
ESP += imm16; /* ??? should it be 2*imm16 ? */
else
SP += imm16;
BX_INSTR_UCNEAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_RET, EIP);
}
void
BX_CPU_C::RETnear16(bxInstruction_c *i)
{
BailBigRSP("RETnear16");
Bit16u return_IP;
//invalidate_prefetch_q();
#if BX_DEBUGGER
BX_CPU_THIS_PTR show_flag |= Flag_ret;
#endif
pop_16(&return_IP);
if (protected_mode()) {
if ( return_IP >
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled ) {
BX_PANIC(("retnear: IP > limit"));
}
}
EIP = return_IP;
BX_INSTR_UCNEAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_RET, EIP);
}
void
BX_CPU_C::RETfar16_Iw(bxInstruction_c *i)
{
BailBigRSP("RETfar16_Iw");
Bit16s imm16;
Bit16u ip, cs_raw;
invalidate_prefetch_q();
#if BX_DEBUGGER
BX_CPU_THIS_PTR show_flag |= Flag_ret;
#endif
/* ??? is imm16, number of bytes/words depending on operandsize ? */
imm16 = i->Iw();
#if BX_CPU_LEVEL >= 2
if (protected_mode()) {
BX_CPU_THIS_PTR return_protected(i, imm16);
goto done;
}
#endif
pop_16(&ip);
pop_16(&cs_raw);
EIP = (Bit32u) ip;
load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], cs_raw);
if (BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache.u.segment.d_b)
ESP += imm16;
else
SP += imm16;
done:
BX_INSTR_FAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_RET,
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value, EIP);
}
void
BX_CPU_C::RETfar16(bxInstruction_c *i)
{
BailBigRSP("RETfar16");
Bit16u ip, cs_raw;
invalidate_prefetch_q();
#if BX_DEBUGGER
BX_CPU_THIS_PTR show_flag |= Flag_ret;
#endif
#if BX_CPU_LEVEL >= 2
if ( protected_mode() ) {
BX_CPU_THIS_PTR return_protected(i, 0);
goto done;
}
#endif
pop_16(&ip);
pop_16(&cs_raw);
EIP = (Bit32u) ip;
load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], cs_raw);
done:
BX_INSTR_FAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_RET,
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value, EIP);
}
void
BX_CPU_C::CALL_Aw(bxInstruction_c *i)
{
BailBigRSP("CALL_Aw");
Bit32u new_EIP;
//invalidate_prefetch_q();
#if BX_DEBUGGER
BX_CPU_THIS_PTR show_flag |= Flag_call;
#endif
new_EIP = EIP + (Bit32s) i->Id();
new_EIP &= 0x0000ffff;
#if BX_CPU_LEVEL >= 2
if ( protected_mode() &&
(new_EIP > BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled) ) {
BX_PANIC(("call_av: new_IP > BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].limit"));
exception(BX_GP_EXCEPTION, 0, 0);
}
#endif
/* push 16 bit EA of next instruction */
push_16(IP);
EIP = new_EIP;
BX_INSTR_UCNEAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_CALL, EIP);
}
void
BX_CPU_C::CALL16_Ap(bxInstruction_c *i)
{
BailBigRSP("CALL16_Ap");
Bit16u cs_raw;
Bit16u disp16;
invalidate_prefetch_q();
#if BX_DEBUGGER
BX_CPU_THIS_PTR show_flag |= Flag_call;
#endif
disp16 = i->Iw();
cs_raw = i->Iw2();
#if BX_CPU_LEVEL >= 2
if (protected_mode()) {
BX_CPU_THIS_PTR call_protected(i, cs_raw, disp16);
goto done;
}
#endif
push_16(BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value);
push_16((Bit16u) EIP);
EIP = (Bit32u) disp16;
load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], cs_raw);
done:
BX_INSTR_FAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_CALL,
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value, EIP);
}
void
BX_CPU_C::CALL_Ew(bxInstruction_c *i)
{
BailBigRSP("CALL_Ew");
Bit16u op1_16;
//invalidate_prefetch_q();
#if BX_DEBUGGER
BX_CPU_THIS_PTR show_flag |= Flag_call;
#endif
if (i->modC0()) {
op1_16 = BX_READ_16BIT_REG(i->rm());
}
else {
read_virtual_word(i->seg(), RMAddr(i), &op1_16);
}
#if BX_CPU_LEVEL >= 2
if (protected_mode()) {
if (op1_16 >
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled) {
BX_PANIC(("call_ev: IP out of CS limits!"));
exception(BX_GP_EXCEPTION, 0, 0);
}
}
#endif
push_16(IP);
EIP = op1_16;
BX_INSTR_UCNEAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_CALL, EIP);
}
void
BX_CPU_C::CALL16_Ep(bxInstruction_c *i)
{
BailBigRSP("CALL_16_Ep");
Bit16u cs_raw;
Bit16u op1_16;
invalidate_prefetch_q();
#if BX_DEBUGGER
BX_CPU_THIS_PTR show_flag |= Flag_call;
#endif
if (i->modC0()) {
BX_PANIC(("CALL_Ep: op1 is a register"));
}
read_virtual_word(i->seg(), RMAddr(i), &op1_16);
read_virtual_word(i->seg(), RMAddr(i)+2, &cs_raw);
if ( protected_mode() ) {
BX_CPU_THIS_PTR call_protected(i, cs_raw, op1_16);
goto done;
}
push_16(BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value);
push_16(IP);
EIP = op1_16;
load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], cs_raw);
done:
BX_INSTR_FAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_CALL,
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value, EIP);
}
void
BX_CPU_C::JMP_Jw(bxInstruction_c *i)
{
BailBigRSP("JMP_Jw");
Bit32u new_EIP;
//invalidate_prefetch_q();
new_EIP = EIP + (Bit32s) i->Id();
new_EIP &= 0x0000ffff;
#if BX_CPU_LEVEL >= 2
if (protected_mode()) {
if ( new_EIP > BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled ) {
BX_PANIC(("jmp_jv: offset outside of CS limits"));
exception(BX_GP_EXCEPTION, 0, 0);
}
}
#endif
EIP = new_EIP;
BX_INSTR_UCNEAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_JMP, new_EIP);
}
void
BX_CPU_C::JCC_Jw(bxInstruction_c *i)
{
BailBigRSP("JCC_Jw");
bx_bool condition;
switch (i->b1() & 0x0f) {
case 0x00: /* JO */ condition = get_OF(); break;
case 0x01: /* JNO */ condition = !get_OF(); break;
case 0x02: /* JB */ condition = get_CF(); break;
case 0x03: /* JNB */ condition = !get_CF(); break;
case 0x04: /* JZ */ condition = get_ZF(); break;
case 0x05: /* JNZ */ condition = !get_ZF(); break;
case 0x06: /* JBE */ condition = get_CF() || get_ZF(); break;
case 0x07: /* JNBE */ condition = !get_CF() && !get_ZF(); break;
case 0x08: /* JS */ condition = get_SF(); break;
case 0x09: /* JNS */ condition = !get_SF(); break;
case 0x0A: /* JP */ condition = get_PF(); break;
case 0x0B: /* JNP */ condition = !get_PF(); break;
case 0x0C: /* JL */ condition = getB_SF() != getB_OF(); break;
case 0x0D: /* JNL */ condition = getB_SF() == getB_OF(); break;
case 0x0E: /* JLE */ condition = get_ZF() || (getB_SF() != getB_OF());
break;
case 0x0F: /* JNLE */ condition = (getB_SF() == getB_OF()) &&
!get_ZF();
break;
default:
condition = 0; // For compiler...all targets should set condition.
break;
}
if (condition) {
Bit32u new_EIP;
new_EIP = EIP + (Bit32s) i->Id();
new_EIP &= 0x0000ffff;
#if BX_CPU_LEVEL >= 2
if (protected_mode()) {
if ( new_EIP >
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled ) {
BX_PANIC(("jo_routine: offset outside of CS limits"));
exception(BX_GP_EXCEPTION, 0, 0);
}
}
#endif
EIP = new_EIP;
BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
revalidate_prefetch_q();
}
#if BX_INSTRUMENTATION
else {
BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}
#endif
}
void
BX_CPU_C::JZ_Jw(bxInstruction_c *i)
{
BailBigRSP("JZ_Jw");
if (get_ZF()) {
Bit32u new_EIP;
new_EIP = EIP + (Bit32s) i->Id();
new_EIP &= 0x0000ffff;
#if BX_CPU_LEVEL >= 2
if (protected_mode()) {
if ( new_EIP >
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled ) {
BX_PANIC(("jo_routine: offset outside of CS limits"));
exception(BX_GP_EXCEPTION, 0, 0);
}
}
#endif
EIP = new_EIP;
BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
revalidate_prefetch_q();
}
#if BX_INSTRUMENTATION
else {
BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}
#endif
}
void
BX_CPU_C::JNZ_Jw(bxInstruction_c *i)
{
BailBigRSP("JNZ_Jw");
if (!get_ZF()) {
Bit32u new_EIP;
new_EIP = EIP + (Bit32s) i->Id();
new_EIP &= 0x0000ffff;
#if BX_CPU_LEVEL >= 2
if (protected_mode()) {
if ( new_EIP >
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled ) {
BX_PANIC(("jo_routine: offset outside of CS limits"));
exception(BX_GP_EXCEPTION, 0, 0);
}
}
#endif
EIP = new_EIP;
BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
revalidate_prefetch_q();
}
#if BX_INSTRUMENTATION
else {
BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}
#endif
}
void
BX_CPU_C::JMP_Ew(bxInstruction_c *i)
{
BailBigRSP("JMP_Ew");
Bit32u new_EIP;
Bit16u op1_16;
//invalidate_prefetch_q();
if (i->modC0()) {
op1_16 = BX_READ_16BIT_REG(i->rm());
}
else {
read_virtual_word(i->seg(), RMAddr(i), &op1_16);
}
new_EIP = op1_16;
#if BX_CPU_LEVEL >= 2
if (protected_mode()) {
if (new_EIP >
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled) {
BX_PANIC(("jmp_ev: IP out of CS limits!"));
exception(BX_GP_EXCEPTION, 0, 0);
}
}
#endif
EIP = new_EIP;
BX_INSTR_UCNEAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_JMP, new_EIP);
}
/* Far indirect jump */
void
BX_CPU_C::JMP16_Ep(bxInstruction_c *i)
{
BailBigRSP("JMP16_Ep");
Bit16u cs_raw;
Bit16u op1_16;
invalidate_prefetch_q();
if (i->modC0()) {
/* far indirect must specify a memory address */
BX_PANIC(("JMP_Ep(): op1 is a register"));
}
read_virtual_word(i->seg(), RMAddr(i), &op1_16);
read_virtual_word(i->seg(), RMAddr(i)+2, &cs_raw);
#if BX_CPU_LEVEL >= 2
if ( protected_mode() ) {
BX_CPU_THIS_PTR jump_protected(i, cs_raw, op1_16);
goto done;
}
#endif
EIP = op1_16;
load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], cs_raw);
done:
BX_INSTR_FAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_JMP,
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value, EIP);
}
void
BX_CPU_C::IRET16(bxInstruction_c *i)
{
BailBigRSP("IRET16");
Bit16u ip, cs_raw, flags;
invalidate_prefetch_q();
#if BX_DEBUGGER
BX_CPU_THIS_PTR show_flag |= Flag_iret;
BX_CPU_THIS_PTR show_eip = EIP;
#endif
if (v8086_mode()) {
// IOPL check in stack_return_from_v86()
stack_return_from_v86(i);
goto done;
}
#if BX_CPU_LEVEL >= 2
if (BX_CPU_THIS_PTR cr0.pe) {
iret_protected(i);
goto done;
}
#endif
pop_16(&ip);
pop_16(&cs_raw);
pop_16(&flags);
load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], cs_raw);
EIP = (Bit32u) ip;
write_flags(flags, /* change IOPL? */ 1, /* change IF? */ 1);
done:
BX_INSTR_FAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_IRET,
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value, EIP);
}