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Added VME emulation to Intel DX4, Pentium and Pentium MMX.

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Temporarily disabled recompilation of CLI and STI.
This commit is contained in:
SarahW 2017-06-30 20:42:19 +01:00
commit 1f33b52451
11 changed files with 259 additions and 62 deletions
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80
src/x86_ops_ret.h
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@ -141,35 +141,67 @@ static int opIRET(uint32_t fetchdat)
if ((cr0 & 1) && (eflags & VM_FLAG) && (IOPL != 3))
{
x86gpf(NULL,0);
return 1;
}
if (msw&1)
{
optype = IRET;
pmodeiret(0);
optype = 0;
}
else
{
uint16_t new_cs;
oxpc = cpu_state.pc;
if (stack32)
if (cr4 & CR4_VME)
{
cpu_state.pc = readmemw(ss, ESP);
new_cs = readmemw(ss, ESP + 2);
flags = (readmemw(ss, ESP + 4) & 0xffd5) | 2;
ESP += 6;
uint16_t new_pc, new_cs, new_flags;
new_pc = readmemw(ss, SP);
new_cs = readmemw(ss, ((SP + 2) & 0xffff));
new_flags = readmemw(ss, ((SP + 4) & 0xffff));
if (cpu_state.abrt)
return 1;
if ((new_flags & T_FLAG) || ((new_flags & I_FLAG) && (eflags & VIP_FLAG)))
{
x86gpf(NULL, 0);
return 1;
}
SP += 6;
if (new_flags & I_FLAG)
eflags |= VIF_FLAG;
else
eflags &= ~VIF_FLAG;
flags = (flags & 0x3300) | (new_flags & 0x4cd5) | 2;
loadcs(new_cs);
cpu_state.pc = new_pc;
cycles -= timing_iret_rm;
}
else
{
cpu_state.pc = readmemw(ss, SP);
new_cs = readmemw(ss, ((SP + 2) & 0xffff));
flags = (readmemw(ss, ((SP + 4) & 0xffff)) & 0xffd5) | 2;
SP += 6;
x86gpf(NULL,0);
return 1;
}
}
else
{
if (msw&1)
{
optype = IRET;
pmodeiret(0);
optype = 0;
}
else
{
uint16_t new_cs;
oxpc = cpu_state.pc;
if (stack32)
{
cpu_state.pc = readmemw(ss, ESP);
new_cs = readmemw(ss, ESP + 2);
flags = (readmemw(ss, ESP + 4) & 0xffd5) | 2;
ESP += 6;
}
else
{
cpu_state.pc = readmemw(ss, SP);
new_cs = readmemw(ss, ((SP + 2) & 0xffff));
flags = (readmemw(ss, ((SP + 4) & 0xffff)) & 0xffd5) | 2;
SP += 6;
}
loadcs(new_cs);
cycles -= timing_iret_rm;
}
loadcs(new_cs);
cycles -= timing_iret_rm;
}
flags_extract();
nmi_enable = 1;