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CPU with softfloat: Added softfloat versions of the i686 FX opcodes while preserving the existing non-softfloat ones.

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TC1995
2023-07-14 21:46:15 +02:00
parent ef05d6a65d
commit f9d5ab39b3
3 changed files with 207 additions and 0 deletions
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132
src/cpu/x86_ops_i686.h
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@@ -43,6 +43,132 @@ opSYSEXIT(uint32_t fetchdat)
return ret;
}
static int
sf_fx_save_stor_common(uint32_t fetchdat, int bits)
{
uint8_t fxinst = 0;
uint32_t tag_byte;
unsigned index;
floatx80 reg;
if (CPUID < 0x650)
return ILLEGAL(fetchdat);
FP_ENTER();
if (bits == 32) {
fetch_ea_32(fetchdat);
} else {
fetch_ea_16(fetchdat);
}
if (cpu_state.eaaddr & 0xf) {
x386_dynarec_log("Effective address %08X not on 16-byte boundary\n", cpu_state.eaaddr);
x86gpf(NULL, 0);
return cpu_state.abrt;
}
fxinst = (rmdat >> 3) & 7;
if ((fxinst > 1) || (cpu_mod == 3)) {
x86illegal();
return cpu_state.abrt;
}
FP_ENTER();
if (fxinst == 1) {
/* FXRSTOR */
fpu_state.cwd = readmemw(easeg, cpu_state.eaaddr);
fpu_state.swd = readmemw(easeg, cpu_state.eaaddr + 2);
fpu_state.tos = (fpu_state.swd >> 11) & 7;
/* always set bit 6 as '1 */
fpu_state.cwd = (fpu_state.cwd & ~FPU_CW_Reserved_Bits) | 0x0040;
/* Restore x87 FPU Opcode */
/* The lower 11 bits contain the FPU opcode, upper 5 bits are reserved */
fpu_state.foo = readmemw(easeg, cpu_state.eaaddr + 6) & 0x7FF;
fpu_state.fip = readmeml(easeg, cpu_state.eaaddr + 8);
fpu_state.fcs = readmemw(easeg, cpu_state.eaaddr + 12);
tag_byte = readmemb(easeg, cpu_state.eaaddr + 4);
fpu_state.fdp = readmeml(easeg, cpu_state.eaaddr + 16);
fpu_state.fds = readmemw(easeg, cpu_state.eaaddr + 20);
/* load i387 register file */
for (index = 0; index < 8; index++) {
reg.fraction = readmemq(easeg, cpu_state.eaaddr + (index * 16) + 32);
reg.exp = readmemw(easeg, cpu_state.eaaddr + (index * 16) + 40);
// update tag only if it is not empty
FPU_save_regi_tag(reg, IS_TAG_EMPTY(index) ? X87_TAG_EMPTY : FPU_tagof(reg), index);
}
fpu_state.tag = unpack_FPU_TW(tag_byte);
/* check for unmasked exceptions */
if (fpu_state.swd & ~fpu_state.cwd & FPU_CW_Exceptions_Mask) {
/* set the B and ES bits in the status-word */
fpu_state.swd |= (FPU_SW_Summary | FPU_SW_Backward);
} else {
/* clear the B and ES bits in the status-word */
fpu_state.swd &= ~(FPU_SW_Summary | FPU_SW_Backward);
}
CLOCK_CYCLES((cr0 & 1) ? 34 : 44);
} else {
/* FXSAVE */
writememw(easeg, cpu_state.eaaddr, i387_get_control_word());
writememw(easeg, cpu_state.eaaddr + 2, i387_get_status_word());
writememw(easeg, cpu_state.eaaddr + 4, pack_FPU_TW(fpu_state.tag));
/* x87 FPU Opcode (16 bits) */
/* The lower 11 bits contain the FPU opcode, upper 5 bits are reserved */
writememw(easeg, cpu_state.eaaddr + 6, fpu_state.foo);
/*
* x87 FPU IP Offset (32/64 bits)
* The contents of this field differ depending on the current
* addressing mode (16/32/64 bit) when the FXSAVE instruction was executed:
* + 64-bit mode - 64-bit IP offset
* + 32-bit mode - 32-bit IP offset
* + 16-bit mode - low 16 bits are IP offset; high 16 bits are reserved.
* x87 CS FPU IP Selector
* + 16 bit, in 16/32 bit mode only
*/
writememl(easeg, cpu_state.eaaddr + 8, fpu_state.fip);
writememl(easeg, cpu_state.eaaddr + 12, fpu_state.fcs);
/*
* x87 FPU Instruction Operand (Data) Pointer Offset (32/64 bits)
* The contents of this field differ depending on the current
* addressing mode (16/32 bit) when the FXSAVE instruction was executed:
* + 64-bit mode - 64-bit offset
* + 32-bit mode - 32-bit offset
* + 16-bit mode - low 16 bits are offset; high 16 bits are reserved.
* x87 DS FPU Instruction Operand (Data) Pointer Selector
* + 16 bit, in 16/32 bit mode only
*/
writememl(easeg, cpu_state.eaaddr + 16, fpu_state.fdp);
writememl(easeg, cpu_state.eaaddr + 20, fpu_state.fds);
/* store i387 register file */
for (index = 0; index < 8; index++) {
const floatx80 fp = FPU_read_regi(index);
writememq(easeg, cpu_state.eaaddr + (index * 16) + 32, fp.fraction);
writememw(easeg, cpu_state.eaaddr + (index * 16) + 40, fp.exp);
}
CLOCK_CYCLES((cr0 & 1) ? 56 : 67);
}
return cpu_state.abrt;
}
static int
fx_save_stor_common(uint32_t fetchdat, int bits)
{
@@ -253,12 +379,18 @@ fx_save_stor_common(uint32_t fetchdat, int bits)
static int
opFXSAVESTOR_a16(uint32_t fetchdat)
{
if (fpu_softfloat)
return sf_fx_save_stor_common(fetchdat, 16);
return fx_save_stor_common(fetchdat, 16);
}
static int
opFXSAVESTOR_a32(uint32_t fetchdat)
{
if (fpu_softfloat)
return sf_fx_save_stor_common(fetchdat, 32);
return fx_save_stor_common(fetchdat, 32);
}