Bochs/bochs/cpu/ctrl_xfer32.cc
2011-02-24 21:54:04 +00:00

830 lines
19 KiB
C++

/////////////////////////////////////////////////////////////////////////
// $Id$
/////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 2001-2009 The Bochs Project
//
// 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., 51 Franklin St, Fifth Floor, Boston, MA B 02110-1301 USA
/////////////////////////////////////////////////////////////////////////
#define NEED_CPU_REG_SHORTCUTS 1
#include "bochs.h"
#include "cpu.h"
#define LOG_THIS BX_CPU_THIS_PTR
// Make code more tidy with a few macros.
#if BX_SUPPORT_X86_64==0
#define RSP ESP
#define RIP EIP
#endif
#if BX_CPU_LEVEL >= 3
BX_CPP_INLINE void BX_CPP_AttrRegparmN(1) BX_CPU_C::branch_near32(Bit32u new_EIP)
{
BX_ASSERT(BX_CPU_THIS_PTR cpu_mode != BX_MODE_LONG_64);
// check always, not only in protected mode
if (new_EIP > BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled)
{
BX_ERROR(("branch_near32: offset outside of CS limits"));
exception(BX_GP_EXCEPTION, 0);
}
EIP = new_EIP;
#if BX_SUPPORT_TRACE_CACHE && !defined(BX_TRACE_CACHE_NO_SPECULATIVE_TRACING)
// assert magic async_event to stop trace execution
BX_CPU_THIS_PTR async_event |= BX_ASYNC_EVENT_STOP_TRACE;
#endif
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::RETnear32_Iw(bxInstruction_c *i)
{
BX_ASSERT(BX_CPU_THIS_PTR cpu_mode != BX_MODE_LONG_64);
#if BX_DEBUGGER
BX_CPU_THIS_PTR show_flag |= Flag_ret;
#endif
RSP_SPECULATIVE;
Bit16u imm16 = i->Iw();
Bit32u return_EIP = pop_32();
if (return_EIP > BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled)
{
BX_ERROR(("RETnear32_Iw: offset outside of CS limits"));
exception(BX_GP_EXCEPTION, 0);
}
EIP = return_EIP;
if (BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache.u.segment.d_b)
ESP += imm16;
else
SP += imm16;
RSP_COMMIT;
BX_INSTR_UCNEAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_RET, EIP);
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::RETnear32(bxInstruction_c *i)
{
BX_ASSERT(BX_CPU_THIS_PTR cpu_mode != BX_MODE_LONG_64);
#if BX_DEBUGGER
BX_CPU_THIS_PTR show_flag |= Flag_ret;
#endif
RSP_SPECULATIVE;
Bit32u return_EIP = pop_32();
if (return_EIP > BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled)
{
BX_ERROR(("RETnear32: offset outside of CS limits"));
exception(BX_GP_EXCEPTION, 0);
}
EIP = return_EIP;
RSP_COMMIT;
BX_INSTR_UCNEAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_RET, EIP);
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::RETfar32_Iw(bxInstruction_c *i)
{
invalidate_prefetch_q();
#if BX_DEBUGGER
BX_CPU_THIS_PTR show_flag |= Flag_ret;
#endif
Bit16u imm16 = i->Iw();
Bit16u cs_raw;
Bit32u eip;
if (protected_mode()) {
return_protected(i, imm16);
goto done;
}
RSP_SPECULATIVE;
eip = pop_32();
cs_raw = (Bit16u) pop_32(); /* 32bit pop, MSW discarded */
// CS.LIMIT can't change when in real/v8086 mode
if (eip > BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled) {
BX_ERROR(("RETfar32_Iw: instruction pointer not within code segment limits"));
exception(BX_GP_EXCEPTION, 0);
}
load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], cs_raw);
EIP = eip;
if (BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache.u.segment.d_b)
ESP += imm16;
else
SP += imm16;
RSP_COMMIT;
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_CPP_AttrRegparmN(1) BX_CPU_C::RETfar32(bxInstruction_c *i)
{
Bit32u eip;
Bit16u cs_raw;
invalidate_prefetch_q();
#if BX_DEBUGGER
BX_CPU_THIS_PTR show_flag |= Flag_ret;
#endif
if (protected_mode()) {
return_protected(i, 0);
goto done;
}
RSP_SPECULATIVE;
eip = pop_32();
cs_raw = (Bit16u) pop_32(); /* 32bit pop, MSW discarded */
// CS.LIMIT can't change when in real/v8086 mode
if (eip > BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled) {
BX_ERROR(("RETfar32: instruction pointer not within code segment limits"));
exception(BX_GP_EXCEPTION, 0);
}
load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], cs_raw);
EIP = eip;
RSP_COMMIT;
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_CPP_AttrRegparmN(1) BX_CPU_C::CALL_Jd(bxInstruction_c *i)
{
#if BX_DEBUGGER
BX_CPU_THIS_PTR show_flag |= Flag_call;
#endif
Bit32u new_EIP = EIP + i->Id();
RSP_SPECULATIVE;
/* push 32 bit EA of next instruction */
push_32(EIP);
branch_near32(new_EIP);
RSP_COMMIT;
BX_INSTR_UCNEAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_CALL, EIP);
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::CALL32_Ap(bxInstruction_c *i)
{
BX_ASSERT(BX_CPU_THIS_PTR cpu_mode != BX_MODE_LONG_64);
Bit16u cs_raw;
Bit32u disp32;
invalidate_prefetch_q();
#if BX_DEBUGGER
BX_CPU_THIS_PTR show_flag |= Flag_call;
#endif
disp32 = i->Id();
cs_raw = i->Iw2();
RSP_SPECULATIVE;
if (protected_mode()) {
call_protected(i, cs_raw, disp32);
goto done;
}
// CS.LIMIT can't change when in real/v8086 mode
if (disp32 > BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled) {
BX_ERROR(("CALL32_Ap: instruction pointer not within code segment limits"));
exception(BX_GP_EXCEPTION, 0);
}
push_32(BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value);
push_32(EIP);
load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], cs_raw);
EIP = disp32;
done:
RSP_COMMIT;
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_CPP_AttrRegparmN(1) BX_CPU_C::CALL_EdR(bxInstruction_c *i)
{
#if BX_DEBUGGER
BX_CPU_THIS_PTR show_flag |= Flag_call;
#endif
Bit32u new_EIP = BX_READ_32BIT_REG(i->rm());
RSP_SPECULATIVE;
/* push 32 bit EA of next instruction */
push_32(EIP);
branch_near32(new_EIP);
RSP_COMMIT;
BX_INSTR_UCNEAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_CALL, EIP);
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::CALL32_Ep(bxInstruction_c *i)
{
Bit16u cs_raw;
Bit32u op1_32;
invalidate_prefetch_q();
#if BX_DEBUGGER
BX_CPU_THIS_PTR show_flag |= Flag_call;
#endif
bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i));
/* pointer, segment address pair */
op1_32 = read_virtual_dword(i->seg(), eaddr);
cs_raw = read_virtual_word (i->seg(), (eaddr+4) & i->asize_mask());
RSP_SPECULATIVE;
if (protected_mode()) {
call_protected(i, cs_raw, op1_32);
goto done;
}
// CS.LIMIT can't change when in real/v8086 mode
if (op1_32 > BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled) {
BX_ERROR(("CALL32_Ep: instruction pointer not within code segment limits"));
exception(BX_GP_EXCEPTION, 0);
}
push_32(BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value);
push_32(EIP);
load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], cs_raw);
EIP = op1_32;
done:
RSP_COMMIT;
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_CPP_AttrRegparmN(1) BX_CPU_C::JMP_Jd(bxInstruction_c *i)
{
Bit32u new_EIP = EIP + (Bit32s) i->Id();
branch_near32(new_EIP);
BX_INSTR_UCNEAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_JMP, new_EIP);
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::JO_Jd(bxInstruction_c *i)
{
if (get_OF()) {
Bit32u new_EIP = EIP + (Bit32s) i->Id();
branch_near32(new_EIP);
BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
}
#if BX_INSTRUMENTATION
else {
BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}
#endif
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::JNO_Jd(bxInstruction_c *i)
{
if (! get_OF()) {
Bit32u new_EIP = EIP + (Bit32s) i->Id();
branch_near32(new_EIP);
BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
}
#if BX_INSTRUMENTATION
else {
BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}
#endif
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::JB_Jd(bxInstruction_c *i)
{
if (get_CF()) {
Bit32u new_EIP = EIP + (Bit32s) i->Id();
branch_near32(new_EIP);
BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
}
#if BX_INSTRUMENTATION
else {
BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}
#endif
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::JNB_Jd(bxInstruction_c *i)
{
if (! get_CF()) {
Bit32u new_EIP = EIP + (Bit32s) i->Id();
branch_near32(new_EIP);
BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
}
#if BX_INSTRUMENTATION
else {
BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}
#endif
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::JZ_Jd(bxInstruction_c *i)
{
if (get_ZF()) {
Bit32u new_EIP = EIP + (Bit32s) i->Id();
branch_near32(new_EIP);
BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
}
#if BX_INSTRUMENTATION
else {
BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}
#endif
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::JNZ_Jd(bxInstruction_c *i)
{
if (! get_ZF()) {
Bit32u new_EIP = EIP + (Bit32s) i->Id();
branch_near32(new_EIP);
BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
}
#if BX_INSTRUMENTATION
else {
BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}
#endif
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::JBE_Jd(bxInstruction_c *i)
{
if (get_CF() || get_ZF()) {
Bit32u new_EIP = EIP + (Bit32s) i->Id();
branch_near32(new_EIP);
BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
}
#if BX_INSTRUMENTATION
else {
BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}
#endif
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::JNBE_Jd(bxInstruction_c *i)
{
if (! (get_CF() || get_ZF())) {
Bit32u new_EIP = EIP + (Bit32s) i->Id();
branch_near32(new_EIP);
BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
}
#if BX_INSTRUMENTATION
else {
BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}
#endif
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::JS_Jd(bxInstruction_c *i)
{
if (get_SF()) {
Bit32u new_EIP = EIP + (Bit32s) i->Id();
branch_near32(new_EIP);
BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
}
#if BX_INSTRUMENTATION
else {
BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}
#endif
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::JNS_Jd(bxInstruction_c *i)
{
if (! get_SF()) {
Bit32u new_EIP = EIP + (Bit32s) i->Id();
branch_near32(new_EIP);
BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
}
#if BX_INSTRUMENTATION
else {
BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}
#endif
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::JP_Jd(bxInstruction_c *i)
{
if (get_PF()) {
Bit32u new_EIP = EIP + (Bit32s) i->Id();
branch_near32(new_EIP);
BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
}
#if BX_INSTRUMENTATION
else {
BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}
#endif
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::JNP_Jd(bxInstruction_c *i)
{
if (! get_PF()) {
Bit32u new_EIP = EIP + (Bit32s) i->Id();
branch_near32(new_EIP);
BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
}
#if BX_INSTRUMENTATION
else {
BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}
#endif
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::JL_Jd(bxInstruction_c *i)
{
if (getB_SF() != getB_OF()) {
Bit32u new_EIP = EIP + (Bit32s) i->Id();
branch_near32(new_EIP);
BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
}
#if BX_INSTRUMENTATION
else {
BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}
#endif
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::JNL_Jd(bxInstruction_c *i)
{
if (getB_SF() == getB_OF()) {
Bit32u new_EIP = EIP + (Bit32s) i->Id();
branch_near32(new_EIP);
BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
}
#if BX_INSTRUMENTATION
else {
BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}
#endif
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::JLE_Jd(bxInstruction_c *i)
{
if (get_ZF() || (getB_SF() != getB_OF())) {
Bit32u new_EIP = EIP + (Bit32s) i->Id();
branch_near32(new_EIP);
BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
}
#if BX_INSTRUMENTATION
else {
BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}
#endif
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::JNLE_Jd(bxInstruction_c *i)
{
if (! get_ZF() && (getB_SF() == getB_OF())) {
Bit32u new_EIP = EIP + (Bit32s) i->Id();
branch_near32(new_EIP);
BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
}
#if BX_INSTRUMENTATION
else {
BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}
#endif
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::JMP_Ap(bxInstruction_c *i)
{
BX_ASSERT(BX_CPU_THIS_PTR cpu_mode != BX_MODE_LONG_64);
Bit32u disp32;
Bit16u cs_raw;
invalidate_prefetch_q();
if (i->os32L()) {
disp32 = i->Id();
}
else {
disp32 = i->Iw();
}
cs_raw = i->Iw2();
// jump_protected doesn't affect ESP so it is ESP safe
if (protected_mode()) {
jump_protected(i, cs_raw, disp32);
goto done;
}
// CS.LIMIT can't change when in real/v8086 mode
if (disp32 > BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled) {
BX_ERROR(("JMP_Ap: instruction pointer not within code segment limits"));
exception(BX_GP_EXCEPTION, 0);
}
load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], cs_raw);
EIP = disp32;
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_CPP_AttrRegparmN(1) BX_CPU_C::JMP_EdR(bxInstruction_c *i)
{
Bit32u new_EIP = BX_READ_32BIT_REG(i->rm());
branch_near32(new_EIP);
BX_INSTR_UCNEAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_JMP, new_EIP);
}
/* Far indirect jump */
void BX_CPP_AttrRegparmN(1) BX_CPU_C::JMP32_Ep(bxInstruction_c *i)
{
Bit16u cs_raw;
Bit32u op1_32;
invalidate_prefetch_q();
bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i));
/* pointer, segment address pair */
op1_32 = read_virtual_dword(i->seg(), eaddr);
cs_raw = read_virtual_word (i->seg(), (eaddr+4) & i->asize_mask());
// jump_protected doesn't affect RSP so it is RSP safe
if (protected_mode()) {
jump_protected(i, cs_raw, op1_32);
goto done;
}
// CS.LIMIT can't change when in real/v8086 mode
if (op1_32 > BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled) {
BX_ERROR(("JMP32_Ep: instruction pointer not within code segment limits"));
exception(BX_GP_EXCEPTION, 0);
}
load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], cs_raw);
EIP = op1_32;
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_CPP_AttrRegparmN(1) BX_CPU_C::IRET32(bxInstruction_c *i)
{
BX_ASSERT(BX_CPU_THIS_PTR cpu_mode != BX_MODE_LONG_64);
invalidate_prefetch_q();
#if BX_SUPPORT_VMX
if (!BX_CPU_THIS_PTR in_vmx_guest || !VMEXIT(VMX_VM_EXEC_CTRL1_NMI_VMEXIT))
#endif
BX_CPU_THIS_PTR disable_NMI = 0;
#if BX_DEBUGGER
BX_CPU_THIS_PTR show_flag |= Flag_iret;
#endif
if (protected_mode()) {
iret_protected(i);
goto done;
}
RSP_SPECULATIVE;
if (v8086_mode()) {
// IOPL check in stack_return_from_v86()
iret32_stack_return_from_v86(i);
}
else {
Bit32u eip = pop_32();
Bit16u cs_raw = (Bit16u) pop_32(); // #SS has higher priority
Bit32u eflags32 = pop_32();
// CS.LIMIT can't change when in real/v8086 mode
if (eip > BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled) {
BX_ERROR(("IRET32: instruction pointer not within code segment limits"));
exception(BX_GP_EXCEPTION, 0);
}
load_seg_reg(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS], cs_raw);
EIP = eip;
writeEFlags(eflags32, 0x00257fd5); // VIF, VIP, VM unchanged
}
RSP_COMMIT;
done:
BX_INSTR_FAR_BRANCH(BX_CPU_ID, BX_INSTR_IS_IRET,
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value, EIP);
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::JECXZ_Jb(bxInstruction_c *i)
{
// it is impossible to get this instruction in long mode
BX_ASSERT(i->as64L() == 0);
Bit32u temp_ECX;
if (i->as32L())
temp_ECX = ECX;
else
temp_ECX = CX;
if (temp_ECX == 0) {
Bit32u new_EIP = EIP + (Bit32s) i->Id();
branch_near32(new_EIP);
BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
}
#if BX_INSTRUMENTATION
else {
BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}
#endif
}
//
// There is some weirdness in LOOP instructions definition. If an exception
// was generated during the instruction execution (for example #GP fault
// because EIP was beyond CS segment limits) CPU state should restore the
// state prior to instruction execution.
//
// The final point that we are not allowed to decrement ECX register before
// it is known that no exceptions can happen.
//
void BX_CPP_AttrRegparmN(1) BX_CPU_C::LOOPNE32_Jb(bxInstruction_c *i)
{
// it is impossible to get this instruction in long mode
BX_ASSERT(i->as64L() == 0);
if (i->as32L()) {
Bit32u count = ECX;
count--;
if (count != 0 && (get_ZF()==0)) {
Bit32u new_EIP = EIP + (Bit32s) i->Id();
branch_near32(new_EIP);
BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
}
#if BX_INSTRUMENTATION
else {
BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}
#endif
ECX = count;
}
else {
Bit16u count = CX;
count--;
if (count != 0 && (get_ZF()==0)) {
Bit32u new_EIP = EIP + (Bit32s) i->Id();
branch_near32(new_EIP);
BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
}
#if BX_INSTRUMENTATION
else {
BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}
#endif
CX = count;
}
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::LOOPE32_Jb(bxInstruction_c *i)
{
// it is impossible to get this instruction in long mode
BX_ASSERT(i->as64L() == 0);
if (i->as32L()) {
Bit32u count = ECX;
count--;
if (count != 0 && get_ZF()) {
Bit32u new_EIP = EIP + (Bit32s) i->Id();
branch_near32(new_EIP);
BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
}
#if BX_INSTRUMENTATION
else {
BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}
#endif
ECX = count;
}
else {
Bit16u count = CX;
count--;
if (count != 0 && get_ZF()) {
Bit32u new_EIP = EIP + (Bit32s) i->Id();
branch_near32(new_EIP);
BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
}
#if BX_INSTRUMENTATION
else {
BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}
#endif
CX = count;
}
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::LOOP32_Jb(bxInstruction_c *i)
{
// it is impossible to get this instruction in long mode
BX_ASSERT(i->as64L() == 0);
if (i->as32L()) {
Bit32u count = ECX;
count--;
if (count != 0) {
Bit32u new_EIP = EIP + (Bit32s) i->Id();
branch_near32(new_EIP);
BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
}
#if BX_INSTRUMENTATION
else {
BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}
#endif
ECX = count;
}
else {
Bit16u count = CX;
count--;
if (count != 0) {
Bit32u new_EIP = EIP + (Bit32s) i->Id();
branch_near32(new_EIP);
BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
}
#if BX_INSTRUMENTATION
else {
BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}
#endif
CX = count;
}
}
#endif