windows-nt/Source/XPSP1/NT/base/wow64/mscpu/fraglib/fputrig.c
2020-09-26 16:20:57 +08:00

974 lines
20 KiB
C

/*++
Copyright (c) 1995-2000 Microsoft Corporation
Module Name:
fputrig.c
Abstract:
Floating point trig and transcendental functions
Author:
05-Oct-1995 BarryBo
Revision History:
--*/
#include <nt.h>
#include <ntrtl.h>
#include <nturtl.h>
#include <windows.h>
#include <float.h>
#include <math.h>
#include <stdio.h>
#include "wx86.h"
#include "cpuassrt.h"
#include "fragp.h"
#include "fpufragp.h"
ASSERTNAME;
//
// Forward declarations
//
NPXFUNC1(FCOS_VALID);
NPXFUNC1(FCOS_ZERO);
NPXFUNC1(FCOS_SPECIAL);
NPXFUNC1(FCOS_EMPTY);
NPXFUNC2(FPATAN_VALID_VALID);
NPXFUNC2(FPATAN_VALID_SPECIAL);
NPXFUNC2(FPATAN_SPECIAL_VALID);
NPXFUNC2(FPATAN_SPECIAL_SPECIAL);
NPXFUNC2(FPATAN_EMPTY_ALL);
NPXFUNC2(FPATAN_ALL_EMPTY);
NPXFUNC0(FPTAN_VALID);
NPXFUNC0(FPTAN_ZERO);
NPXFUNC0(FPTAN_SPECIAL);
NPXFUNC0(FSIN_VALID);
NPXFUNC0(FSIN_ZERO);
NPXFUNC0(FSIN_SPECIAL);
NPXFUNC0(FSIN_EMPTY);
NPXFUNC0(FSINCOS_VALID);
NPXFUNC0(FSINCOS_ZERO);
NPXFUNC0(FSINCOS_SPECIAL);
NPXFUNC2(FYL2X_VALID_VALID);
NPXFUNC2(FYL2X_VALID_ZERO);
NPXFUNC2(FYL2X_ZERO_VALID);
NPXFUNC2(FYL2X_ZERO_ZERO);
NPXFUNC2(FYL2X_SPECIAL_VALIDORZERO);
NPXFUNC2(FYL2X_VALIDORZERO_SPECIAL);
NPXFUNC2(FYL2X_SPECIAL_SPECIAL);
NPXFUNC2(FYL2X_ANY_EMPTY);
NPXFUNC2(FYL2X_EMPTY_ANY);
NPXFUNC2(FYL2XP1_VALIDORZERO_ZERO);
NPXFUNC2(FYL2XP1_VALIDORZERO_VALID);
NPXFUNC2(FYL2XP1_SPECIAL_VALIDORZERO);
NPXFUNC2(FYL2XP1_VALIDORZERO_SPECIAL);
NPXFUNC2(FYL2XP1_SPECIAL_SPECIAL);
NPXFUNC2(FYL2XP1_ANY_EMPTY);
NPXFUNC2(FYL2XP1_EMPTY_ANY);
NPXFUNC1(F2XM1_VALID);
NPXFUNC1(F2XM1_ZERO);
NPXFUNC1(F2XM1_SPECIAL);
NPXFUNC1(F2XM1_EMPTY);
//
// Jump tables
//
const NpxFunc1 FCOSTable[TAG_MAX] = {
FCOS_VALID,
FCOS_ZERO,
FCOS_SPECIAL,
FCOS_EMPTY
};
const NpxFunc2 FPATANTable[TAG_MAX][TAG_MAX] = {
// left = TAG_VALID, right is ...
{ FPATAN_VALID_VALID, FPATAN_VALID_VALID, FPATAN_VALID_SPECIAL, FPATAN_ALL_EMPTY },
// left = TAG_ZERO, right is ...
{ FPATAN_VALID_VALID, FPATAN_VALID_VALID, FPATAN_VALID_SPECIAL, FPATAN_ALL_EMPTY },
// left = TAG_SPECIAL, right is ...
{ FPATAN_SPECIAL_VALID, FPATAN_SPECIAL_VALID, FPATAN_SPECIAL_SPECIAL, FPATAN_ALL_EMPTY },
// left = TAG_EMPTY, right is ...
{ FPATAN_EMPTY_ALL, FPATAN_EMPTY_ALL, FPATAN_EMPTY_ALL, FPATAN_EMPTY_ALL }
};
const NpxFunc0 FPTANTable[TAG_MAX-1] = {
FPTAN_VALID,
FPTAN_ZERO,
FPTAN_SPECIAL
};
const NpxFunc0 FSINTable[TAG_MAX] = {
FSIN_VALID,
FSIN_ZERO,
FSIN_SPECIAL,
FSIN_EMPTY
};
const NpxFunc0 FSINCOSTable[TAG_MAX-1] = {
FSINCOS_VALID,
FSINCOS_ZERO,
FSINCOS_SPECIAL
};
// In the functions, l == ST(0), r = ST(1)
// r = r*log(l), l must be > 0
const NpxFunc2 FYL2XTable[TAG_MAX][TAG_MAX] = {
// left is TAG_VALID, right is ...
{ FYL2X_VALID_VALID, FYL2X_VALID_ZERO, FYL2X_VALIDORZERO_SPECIAL, FYL2X_ANY_EMPTY },
// left is TAG_ZERO, right is ...
{ FYL2X_ZERO_VALID, FYL2X_ZERO_ZERO, FYL2X_VALIDORZERO_SPECIAL, FYL2X_ANY_EMPTY },
// left is TAG_SPECIAL, right is ...
{ FYL2X_SPECIAL_VALIDORZERO, FYL2X_SPECIAL_VALIDORZERO, FYL2X_SPECIAL_SPECIAL, FYL2X_ANY_EMPTY },
// left is TAG_EMPTY, right is ...
{ FYL2X_EMPTY_ANY, FYL2X_EMPTY_ANY, FYL2X_EMPTY_ANY, FYL2X_EMPTY_ANY}
};
// In the functions, l == ST(0), r = ST(1)
// r = r*(logl+1), l must be > 1
const NpxFunc2 FYL2XP1Table[TAG_MAX][TAG_MAX] = {
// left is TAG_VALID, right is ...
{ FYL2XP1_VALIDORZERO_VALID, FYL2XP1_VALIDORZERO_ZERO, FYL2XP1_VALIDORZERO_SPECIAL, FYL2XP1_ANY_EMPTY },
// left is TAG_ZERO, right is ...
{ FYL2XP1_VALIDORZERO_VALID, FYL2XP1_VALIDORZERO_ZERO, FYL2XP1_VALIDORZERO_SPECIAL, FYL2X_ANY_EMPTY },
// left is TAG_SPECIAL, right is ...
{ FYL2XP1_SPECIAL_VALIDORZERO, FYL2XP1_SPECIAL_VALIDORZERO, FYL2XP1_SPECIAL_SPECIAL, FYL2XP1_ANY_EMPTY },
// left is TAG_EMPTY, right is ...
{ FYL2XP1_EMPTY_ANY, FYL2XP1_EMPTY_ANY, FYL2XP1_EMPTY_ANY, FYL2XP1_EMPTY_ANY}
};
const NpxFunc1 F2XM1Table[TAG_MAX] = {
F2XM1_VALID,
F2XM1_ZERO,
F2XM1_SPECIAL,
F2XM1_EMPTY
};
NPXFUNC1(FCOS_VALID)
{
Fp->r64 = cos(Fp->r64);
SetTag(Fp);
}
NPXFUNC1(FCOS_ZERO)
{
Fp->Tag = TAG_VALID;
Fp->r64 = 1.0;
}
NPXFUNC1(FCOS_SPECIAL)
{
switch (Fp->TagSpecial) {
case TAG_SPECIAL_DENORM:
FCOS_VALID(cpu, Fp);
break;
case TAG_SPECIAL_INFINITY:
cpu->FpStatusC2 = 1;
SetIndefinite(Fp);
break;
case TAG_SPECIAL_SNAN:
HandleSnan(cpu, Fp);
break;
case TAG_SPECIAL_QNAN:
case TAG_SPECIAL_INDEF:
HandleInvalidOp(cpu);
break;
}
}
NPXFUNC1(FCOS_EMPTY)
{
HandleStackEmpty(cpu, Fp);
}
FRAG0(FCOS)
{
PFPREG ST0;
FpArithPreamble(cpu);
cpu->FpStatusC2 = 0;
ST0 = cpu->FpST0;
(*FCOSTable[ST0->Tag])(cpu, ST0);
}
NPXFUNC2(FPATAN_VALID_VALID)
{
l->r64 = Proxyatan2(l->r64, r->r64);
SetTag(l);
POPFLT;
}
NPXFUNC2(FPATAN_VALID_SPECIAL)
{
switch (r->TagSpecial) {
case TAG_SPECIAL_DENORM:
case TAG_SPECIAL_INFINITY:
FPATAN_VALID_VALID(cpu, l, r);
break;
case TAG_SPECIAL_SNAN:
if (HandleSnan(cpu, r)) {
break;
}
// else fall into QNAN
case TAG_SPECIAL_QNAN:
case TAG_SPECIAL_INDEF:
// return the QNAN as the result
l->r64 = r->r64;
l->Tag = TAG_SPECIAL;
l->TagSpecial = r->TagSpecial;
POPFLT;
break;
}
}
NPXFUNC2(FPATAN_SPECIAL_VALID)
{
switch (l->TagSpecial) {
case TAG_SPECIAL_DENORM:
case TAG_SPECIAL_INFINITY:
FPATAN_VALID_VALID(cpu, l, r);
break;
case TAG_SPECIAL_SNAN:
if (HandleSnan(cpu, l)) {
break;
}
// else fall into QNAN
case TAG_SPECIAL_QNAN:
case TAG_SPECIAL_INDEF:
// The QNAN is already in l, so nothing to do.
POPFLT;
break;
}
}
NPXFUNC2(FPATAN_SPECIAL_SPECIAL)
{
if (l->TagSpecial == TAG_SPECIAL_SNAN && HandleSnan(cpu, l)) {
return;
}
if (r->TagSpecial == TAG_SPECIAL_SNAN && HandleSnan(cpu, r)) {
return;
}
if (IS_TAG_NAN(l)) {
if (IS_TAG_NAN(r)) {
//
// Return the larger of the two NANs
//
l->r64 = l->r64 + r->r64;
SetTag(l);
}
//
// else l is a NAN and r isn't - return the NAN in l
//
POPFLT;
return;
}
if (IS_TAG_NAN(r)) {
// r is a NAN and l isn't - return the NAN in l
l->r64 = r->r64;
l->Tag = TAG_SPECIAL;
l->TagSpecial = r->TagSpecial;
POPFLT;
}
// Otherwise, l and r are both INFINITY. Return INDEFINITE
CPUASSERT(l->TagSpecial == TAG_SPECIAL_INFINITY &&
r->TagSpecial == TAG_SPECIAL_INFINITY);
SetIndefinite(l);
POPFLT;
}
NPXFUNC2(FPATAN_EMPTY_ALL)
{
if (!HandleStackEmpty(cpu, l)) {
(*FPATANTable[TAG_SPECIAL][r->Tag])(cpu, l, r);
}
}
NPXFUNC2(FPATAN_ALL_EMPTY)
{
if (!HandleStackEmpty(cpu, r)) {
(*FPATANTable[l->Tag][TAG_SPECIAL])(cpu, l, r);
}
}
FRAG0(FPATAN)
{
PFPREG l = &cpu->FpStack[ST(1)];
PFPREG r = cpu->FpST0;
FpArithPreamble(cpu);
(*FPATANTable[l->Tag][r->Tag])(cpu, l, r);
}
NPXFUNC0(FPTAN_VALID)
{
int Exponent;
PFPREG ST0;
// get the exponent and make sure it is < 63
ST0 = cpu->FpST0;
Exponent = (int)((ST0->rdw[1] >> 20) & 0x7ff) - 1023;
if (Exponent >= 63) {
cpu->FpStatusC2 = 1;
return;
}
ST0->r64 = tan(ST0->r64);
SetTag(ST0);
PUSHFLT(ST0);
ST0->Tag = TAG_VALID;
ST0->r64 = 1.0;
}
NPXFUNC0(FPTAN_ZERO)
{
PFPREG ST0;
ST0=cpu->FpST0;
ST0->r64 = 0.0;
ST0->Tag = TAG_ZERO;
PUSHFLT(ST0);
ST0->r64 = 1.0;
ST0->Tag = TAG_VALID;
}
NPXFUNC0(FPTAN_SPECIAL)
{
if (cpu->FpST0->TagSpecial == TAG_SPECIAL_SNAN && HandleSnan(cpu, cpu->FpST0)) {
return;
} else if (cpu->FpST0->TagSpecial == TAG_SPECIAL_DENORM) {
FPTAN_VALID(cpu);
}
cpu->FpStatusC2 = 1;
}
FRAG0(FPTAN)
{
PFPREG ST0;
FpArithPreamble(cpu);
ST0 = cpu->FpST0;
//
// TAG_EMPTY is handled first so that we can check ST(7) before
// anything else has a chance to raise an exception.
//
if (ST0->Tag == TAG_EMPTY && HandleStackEmpty(cpu, ST0)) {
return;
}
if (cpu->FpStack[ST(7)].Tag != TAG_EMPTY) {
HandleStackFull(cpu, &cpu->FpStack[ST(7)]);
return;
}
// assume no error
cpu->FpStatusC2 = 0;
// calculate the value
CPUASSERT(ST0->Tag < TAG_EMPTY); // EMPTY was already handled
(*FPTANTable[ST0->Tag])(cpu);
}
NPXFUNC0(FSIN_VALID)
{
PFPREG ST0;
ST0 = cpu->FpST0;
ST0->r64 = sin(ST0->r64);
SetTag(ST0);
}
NPXFUNC0(FSIN_ZERO)
{
// sin(0.0) == 0.0, so there is nothing to do
}
NPXFUNC0(FSIN_SPECIAL)
{
if (cpu->FpST0->TagSpecial == TAG_SPECIAL_SNAN && HandleSnan(cpu, cpu->FpST0)) {
return;
} else if (cpu->FpST0->TagSpecial == TAG_SPECIAL_DENORM) {
FSIN_VALID(cpu);
}
cpu->FpStatusC2 = 1;
}
NPXFUNC0(FSIN_EMPTY)
{
if (!HandleStackEmpty(cpu, cpu->FpST0)) {
cpu->FpStatusC2 = 1;
}
}
FRAG0(FSIN)
{
FpArithPreamble(cpu);
// assume no error
cpu->FpStatusC2 = 0;
// calculate the value
(*FSINTable[cpu->FpST0->Tag])(cpu);
}
NPXFUNC0(FSINCOS_VALID)
{
DOUBLE Val;
PFPREG ST0;
ST0 = cpu->FpST0;
Val = ST0->r64;
ST0->r64 = sin(Val);
SetTag(ST0);
PUSHFLT(ST0);
ST0->r64 = cos(Val);
SetTag(ST0);
}
NPXFUNC0(FSINCOS_ZERO)
{
PFPREG ST0;
ST0=cpu->FpST0;
ST0->r64 = 0.0;
ST0->Tag = TAG_ZERO;
PUSHFLT(ST0);
ST0->r64 = 1.0;
ST0->Tag = TAG_VALID;
}
NPXFUNC0(FSINCOS_SPECIAL)
{
switch (cpu->FpST0->TagSpecial) {
case TAG_SPECIAL_DENORM:
FSINCOS_VALID(cpu);
break;
case TAG_SPECIAL_INFINITY:
cpu->FpStatusC2 = 1;
SetIndefinite(cpu->FpST0);
break;
case TAG_SPECIAL_SNAN:
if (HandleSnan(cpu, cpu->FpST0)) {
return;
}
// else fall into TAG_SPECIAL_QNAN
case TAG_SPECIAL_QNAN:
case TAG_SPECIAL_INDEF:
cpu->FpStatusC2 = 1;
break;
}
}
FRAG0(FSINCOS)
{
PFPREG ST0;
FpArithPreamble(cpu);
// assume no errors
cpu->FpStatusC2 = 0;
ST0 = cpu->FpST0;
if (ST0->Tag == TAG_EMPTY && HandleStackEmpty(cpu, ST0)) {
return;
}
if (cpu->FpStack[ST(7)].Tag != TAG_EMPTY) {
HandleStackFull(cpu, &cpu->FpStack[ST(7)]);
return;
}
CPUASSERT(ST0->Tag < TAG_EMPTY); // EMPTY was already handled
(*FSINCOSTable[ST0->Tag])(cpu);
}
NPXFUNC2(FYL2X_VALID_VALID)
{
if (l->r64 < 0.0) {
// ST0 is negative - invalid operation
if (!HandleInvalidOp(cpu)) {
SetIndefinite(r);
POPFLT;
}
return;
}
// r = r * log10(l->r64) / log10(2)
//
r->r64 *= Proxylog10(l->r64) / (0.301029995664);
SetTag(r);
POPFLT;
}
NPXFUNC2(FYL2X_VALID_ZERO)
{
if (l->r64 < 0.0) {
// ST0 is negative - invalid operation
if (!HandleInvalidOp(cpu)) {
SetIndefinite(r);
POPFLT;
}
return;
}
// r = r*log2(l), but r=0, so the answer is 0.
r->r64 = 0;
r->Tag = TAG_ZERO;
POPFLT;
}
NPXFUNC2(FYL2X_ZERO_VALID)
{
// Divide-by-zero error
cpu->FpStatusExceptions |= FPCONTROL_ZM;
if (cpu->FpControlMask & FPCONTROL_ZM) {
// Zero-divide exception is masked - return -INFINITY
r->r64 = R8NegativeInfinity;
r->Tag = TAG_SPECIAL;
r->TagSpecial = TAG_SPECIAL_INFINITY;
POPFLT;
} else {
cpu->FpStatusES = 1;
}
}
NPXFUNC2(FYL2X_ZERO_ZERO)
{
if (!HandleInvalidOp(cpu)) {
SetIndefinite(r);
POPFLT;
}
}
NPXFUNC2(FYL2X_SPECIAL_VALIDORZERO)
{
switch (l->TagSpecial) {
case TAG_SPECIAL_DENORM:
(*FYL2XTable[TAG_VALID][r->Tag])(cpu, l, r);
break;
case TAG_SPECIAL_INFINITY:
if (r->Tag == TAG_ZERO || r->rb[7] & 0x80) {
// 0*infinity, or anything*-infinity
SetIndefinite(r);
} else {
// return -infinity
r->rb[7] |= 0x80;
}
POPFLT;
break;
case TAG_SPECIAL_SNAN:
if (HandleSnan(cpu, l)) {
return;
}
// else fall into TAG_SPECIAL_QNAN
case TAG_SPECIAL_QNAN:
case TAG_SPECIAL_INDEF:
// l is a NAN and r is VALID or ZERO - return the NAN
r->r64 = l->r64;
r->Tag = l->Tag;
r->TagSpecial = r->TagSpecial;
POPFLT;
break;
}
}
NPXFUNC2(FYL2X_VALIDORZERO_SPECIAL)
{
switch (r->TagSpecial) {
case TAG_SPECIAL_DENORM:
(*FYL2XTable[l->Tag][TAG_VALID])(cpu, l, r);
break;
case TAG_SPECIAL_INFINITY:
// log(x)*infinity
if (l->r64 > 1.0) {
// return the original infinity - nothing to do
} else if (l->r64 < 0.0 || l->r64 == 1.0) {
if (HandleInvalidOp(cpu)) {
return;
}
SetIndefinite(r);
} else {
// return infinity with sign flipped
r->rb[7] ^= 0x80;
}
POPFLT;
break;
case TAG_SPECIAL_SNAN:
if (HandleSnan(cpu, r)) {
return;
}
// else fall into TAG_SPECIAL_QNAN
case TAG_SPECIAL_QNAN:
case TAG_SPECIAL_INDEF:
// r is a NAN and l is VALID or ZERO - return the NAN
POPFLT;
break;
}
}
NPXFUNC2(FYL2X_SPECIAL_SPECIAL)
{
if (l->TagSpecial == TAG_SPECIAL_SNAN && HandleStackEmpty(cpu, l)) {
return;
}
if (r->TagSpecial == TAG_SPECIAL_SNAN && HandleStackEmpty(cpu, r)) {
return;
}
if (l->TagSpecial == TAG_SPECIAL_DENORM) {
(*FYL2XTable[TAG_VALID][r->Tag])(cpu, l, r);
return;
}
if (r->TagSpecial == TAG_SPECIAL_DENORM) {
(*FYL2XTable[l->Tag][TAG_VALID])(cpu, l, r);
return;
}
if (l->Tag == TAG_SPECIAL_INFINITY) {
if (r->Tag == TAG_SPECIAL_INFINITY) {
// two infinities - return INDEFINITE
SetIndefinite(r);
} else {
CPUASSERT(IS_TAG_NAN(r));
// r already has the NAN to return
}
} else {
CPUASSERT(IS_TAG_NAN(l));
if (r->Tag == TAG_SPECIAL_INFINITY) {
//
// Return the NAN from l
//
r->r64 = l->r64;
r->TagSpecial = l->TagSpecial;
} else {
//
// Return the largest of the two NANs
//
r->r64 = l->r64 + r->r64;
SetTag(r);
}
}
POPFLT;
}
NPXFUNC2(FYL2X_ANY_EMPTY)
{
if (!HandleStackEmpty(cpu, r)) {
(*FYL2XTable[l->Tag][TAG_SPECIAL])(cpu, l, r);
}
}
NPXFUNC2(FYL2X_EMPTY_ANY)
{
if (!HandleStackEmpty(cpu, l)) {
(*FYL2XTable[TAG_SPECIAL][r->Tag])(cpu, l, r);
}
}
FRAG0(FYL2X)
{
PFPREG l, r;
FpArithPreamble(cpu);
l = cpu->FpST0;
r = &cpu->FpStack[ST(1)];
// In the functions, l == ST(0), r = ST(1)
(*FYL2XTable[l->Tag][r->Tag])(cpu, l, r);
}
NPXFUNC2(FYL2XP1_VALIDORZERO_VALID)
{
if (l->r64 < -1.0) {
if (!HandleInvalidOp(cpu)) {
SetIndefinite(r);
POPFLT;
}
return;
} else if (l->r64 == -1.0) {
// Divide-by-zero error
cpu->FpStatusExceptions |= FPCONTROL_ZM;
if (cpu->FpControlMask & FPCONTROL_ZM) {
// Zero-divide exception is masked - return -INFINITY
r->r64 = R8NegativeInfinity;
r->Tag = TAG_SPECIAL;
r->TagSpecial = TAG_SPECIAL_INFINITY;
POPFLT;
} else {
cpu->FpStatusES = 1;
}
return;
}
// r = r * log10(l+1) / log10(2)
//
r->r64 *= Proxylog10(l->r64 + 1.0) / (0.301029995664);
SetTag(r);
POPFLT;
}
NPXFUNC2(FYL2XP1_VALIDORZERO_ZERO)
{
if (l->r64 < -1.0) {
if (!HandleInvalidOp(cpu)) {
SetIndefinite(r);
POPFLT;
}
return;
}
// r = r*log2(l), but r=0, so the answer is 0.
r->r64 = 0;
r->Tag = TAG_ZERO;
POPFLT;
}
NPXFUNC2(FYL2XP1_SPECIAL_VALIDORZERO)
{
switch (l->TagSpecial) {
case TAG_SPECIAL_DENORM:
(*FYL2XP1Table[TAG_VALID][r->Tag])(cpu, l, r);
break;
case TAG_SPECIAL_INFINITY:
if (r->Tag == TAG_ZERO || r->rb[7] & 0x80) {
if (HandleInvalidOp(cpu)) {
return;
}
// 0*infinity, or anything*-infinity
SetIndefinite(r);
} else {
// return -infinity
r->rb[7] |= 0x80;
}
POPFLT;
break;
case TAG_SPECIAL_SNAN:
if (HandleSnan(cpu, l)) {
return;
}
// else fall into TAG_SPECIAL_QNAN
case TAG_SPECIAL_QNAN:
case TAG_SPECIAL_INDEF:
// l is a NAN and r is VALID or ZERO - return the NAN
r->r64 = l->r64;
r->Tag = l->Tag;
r->TagSpecial = r->TagSpecial;
POPFLT;
break;
}
}
NPXFUNC2(FYL2XP1_VALIDORZERO_SPECIAL)
{
switch (r->TagSpecial) {
case TAG_SPECIAL_DENORM:
(*FYL2XP1Table[l->Tag][TAG_VALID])(cpu, l, r);
break;
case TAG_SPECIAL_INFINITY:
// log(x)*infinity
if (l->r64 > 1.0) {
// return the original infinity - nothing to do
} else if (l->r64 < 0.0 || l->r64 == 1.0) {
if (HandleInvalidOp(cpu)) {
return;
}
SetIndefinite(r);
} else {
// return infinity with sign flipped
r->rb[7] ^= 0x80;
}
POPFLT;
break;
case TAG_SPECIAL_SNAN:
if (HandleSnan(cpu, r)) {
return;
}
// else fall into TAG_SPECIAL_QNAN
case TAG_SPECIAL_QNAN:
case TAG_SPECIAL_INDEF:
// r is a NAN and l is VALID or ZERO - return the NAN
POPFLT;
break;
}
}
NPXFUNC2(FYL2XP1_SPECIAL_SPECIAL)
{
if (l->TagSpecial == TAG_SPECIAL_SNAN && HandleStackEmpty(cpu, l)) {
return;
}
if (r->TagSpecial == TAG_SPECIAL_SNAN && HandleStackEmpty(cpu, r)) {
return;
}
if (l->TagSpecial == TAG_SPECIAL_DENORM) {
(*FYL2XP1Table[TAG_VALID][r->Tag])(cpu, l, r);
return;
}
if (r->TagSpecial == TAG_SPECIAL_DENORM) {
(*FYL2XP1Table[l->Tag][TAG_VALID])(cpu, l, r);
return;
}
if (l->Tag == TAG_SPECIAL_INFINITY) {
if (r->Tag == TAG_SPECIAL_INFINITY) {
if (l->rb[7] & 0x80) {
// l is negative infinity. Invalid op
if (HandleInvalidOp(cpu)) {
return;
}
SetIndefinite(r);
}
} else {
CPUASSERT(IS_TAG_NAN(r));
// r already has the NAN to return
}
} else {
CPUASSERT(IS_TAG_NAN(l));
if (r->Tag == TAG_SPECIAL_INFINITY) {
//
// Return the NAN from l
//
r->r64 = l->r64;
r->TagSpecial = l->TagSpecial;
} else {
//
// Return the largest of the two NANs
//
r->r64 = l->r64 + r->r64;
SetTag(r);
}
}
POPFLT;
}
NPXFUNC2(FYL2XP1_ANY_EMPTY)
{
if (!HandleStackEmpty(cpu, r)) {
(*FYL2XP1Table[l->Tag][TAG_SPECIAL])(cpu, l, r);
}
}
NPXFUNC2(FYL2XP1_EMPTY_ANY)
{
if (!HandleStackEmpty(cpu, l)) {
(*FYL2XP1Table[TAG_SPECIAL][r->Tag])(cpu, l, r);
}
}
FRAG0(FYL2XP1)
{
PFPREG l, r;
FpArithPreamble(cpu);
l = cpu->FpST0;
r = &cpu->FpStack[ST(1)];
// In the functions, l == ST(0), r = ST(1)
(*FYL2XP1Table[l->Tag][r->Tag])(cpu, l, r);
}
NPXFUNC1(F2XM1_VALID)
{
Fp->r64 = pow(2.0, Fp->r64) - 1.0;
SetTag(Fp);
}
NPXFUNC1(F2XM1_ZERO)
{
// nothing to do - return the same zero
}
NPXFUNC1(F2XM1_SPECIAL)
{
switch (Fp->TagSpecial) {
case TAG_SPECIAL_DENORM:
F2XM1_VALID(cpu, Fp);
break;
case TAG_SPECIAL_INFINITY:
if (Fp->rb[7] & 0x80) {
// -infinity - return 1
Fp->r64 = 1.0;
Fp->Tag = TAG_VALID;
}
// else +infinity - return +infinity
break;
case TAG_SPECIAL_SNAN:
HandleSnan(cpu, Fp);
// fall into TAG_SPECIAL_QNAN
case TAG_SPECIAL_QNAN:
case TAG_SPECIAL_INDEF:
// return the NAN
break;
}
}
NPXFUNC1(F2XM1_EMPTY)
{
HandleStackEmpty(cpu, Fp);
}
FRAG0(F2XM1)
{
PFPREG ST0;
FpArithPreamble(cpu);
ST0 = cpu->FpST0;
(*F2XM1Table[ST0->Tag])(cpu, ST0);
}