citra/src/core/arm/skyeye_common/vfp/vfp_helper.h

451 lines
13 KiB
C

/*
vfp/vfp.h - ARM VFPv3 emulation unit - SoftFloat lib helper
Copyright (C) 2003 Skyeye Develop Group
for help please send mail to <skyeye-developer@lists.gro.clinux.org>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
* The following code is derivative from Linux Android kernel vfp
* floating point support.
*
* Copyright (C) 2004 ARM Limited.
* Written by Deep Blue Solutions Limited.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#pragma once
#include <cstdio>
#include "common/common_types.h"
#include "core/arm/skyeye_common/armdefs.h"
#include "core/arm/skyeye_common/vfp/asm_vfp.h"
#define do_div(n, base) {n/=base;}
enum : u32 {
FOP_MASK = 0x00b00040,
FOP_FMAC = 0x00000000,
FOP_FNMAC = 0x00000040,
FOP_FMSC = 0x00100000,
FOP_FNMSC = 0x00100040,
FOP_FMUL = 0x00200000,
FOP_FNMUL = 0x00200040,
FOP_FADD = 0x00300000,
FOP_FSUB = 0x00300040,
FOP_FDIV = 0x00800000,
FOP_EXT = 0x00b00040
};
#define FOP_TO_IDX(inst) ((inst & 0x00b00000) >> 20 | (inst & (1 << 6)) >> 4)
enum : u32 {
FEXT_MASK = 0x000f0080,
FEXT_FCPY = 0x00000000,
FEXT_FABS = 0x00000080,
FEXT_FNEG = 0x00010000,
FEXT_FSQRT = 0x00010080,
FEXT_FCMP = 0x00040000,
FEXT_FCMPE = 0x00040080,
FEXT_FCMPZ = 0x00050000,
FEXT_FCMPEZ = 0x00050080,
FEXT_FCVT = 0x00070080,
FEXT_FUITO = 0x00080000,
FEXT_FSITO = 0x00080080,
FEXT_FTOUI = 0x000c0000,
FEXT_FTOUIZ = 0x000c0080,
FEXT_FTOSI = 0x000d0000,
FEXT_FTOSIZ = 0x000d0080
};
#define FEXT_TO_IDX(inst) ((inst & 0x000f0000) >> 15 | (inst & (1 << 7)) >> 7)
#define vfp_get_sd(inst) ((inst & 0x0000f000) >> 11 | (inst & (1 << 22)) >> 22)
#define vfp_get_dd(inst) ((inst & 0x0000f000) >> 12 | (inst & (1 << 22)) >> 18)
#define vfp_get_sm(inst) ((inst & 0x0000000f) << 1 | (inst & (1 << 5)) >> 5)
#define vfp_get_dm(inst) ((inst & 0x0000000f) | (inst & (1 << 5)) >> 1)
#define vfp_get_sn(inst) ((inst & 0x000f0000) >> 15 | (inst & (1 << 7)) >> 7)
#define vfp_get_dn(inst) ((inst & 0x000f0000) >> 16 | (inst & (1 << 7)) >> 3)
#define vfp_single(inst) (((inst) & 0x0000f00) == 0xa00)
static inline u32 vfp_shiftright32jamming(u32 val, unsigned int shift)
{
if (shift) {
if (shift < 32)
val = val >> shift | ((val << (32 - shift)) != 0);
else
val = val != 0;
}
return val;
}
static inline u64 vfp_shiftright64jamming(u64 val, unsigned int shift)
{
if (shift) {
if (shift < 64)
val = val >> shift | ((val << (64 - shift)) != 0);
else
val = val != 0;
}
return val;
}
static inline u32 vfp_hi64to32jamming(u64 val)
{
u32 v;
u32 highval = val >> 32;
u32 lowval = val & 0xffffffff;
if (lowval >= 1)
v = highval | 1;
else
v = highval;
return v;
}
static inline void add128(u64* resh, u64* resl, u64 nh, u64 nl, u64 mh, u64 ml)
{
*resl = nl + ml;
*resh = nh + mh;
if (*resl < nl)
*resh += 1;
}
static inline void sub128(u64* resh, u64* resl, u64 nh, u64 nl, u64 mh, u64 ml)
{
*resl = nl - ml;
*resh = nh - mh;
if (*resl > nl)
*resh -= 1;
}
static inline void mul64to128(u64* resh, u64* resl, u64 n, u64 m)
{
u32 nh, nl, mh, ml;
u64 rh, rma, rmb, rl;
nl = static_cast<u32>(n);
ml = static_cast<u32>(m);
rl = (u64)nl * ml;
nh = n >> 32;
rma = (u64)nh * ml;
mh = m >> 32;
rmb = (u64)nl * mh;
rma += rmb;
rh = (u64)nh * mh;
rh += ((u64)(rma < rmb) << 32) + (rma >> 32);
rma <<= 32;
rl += rma;
rh += (rl < rma);
*resl = rl;
*resh = rh;
}
static inline void shift64left(u64* resh, u64* resl, u64 n)
{
*resh = n >> 63;
*resl = n << 1;
}
static inline u64 vfp_hi64multiply64(u64 n, u64 m)
{
u64 rh, rl;
mul64to128(&rh, &rl, n, m);
return rh | (rl != 0);
}
static inline u64 vfp_estimate_div128to64(u64 nh, u64 nl, u64 m)
{
u64 mh, ml, remh, reml, termh, terml, z;
if (nh >= m)
return ~0ULL;
mh = m >> 32;
if (mh << 32 <= nh) {
z = 0xffffffff00000000ULL;
} else {
z = nh;
do_div(z, mh);
z <<= 32;
}
mul64to128(&termh, &terml, m, z);
sub128(&remh, &reml, nh, nl, termh, terml);
ml = m << 32;
while ((s64)remh < 0) {
z -= 0x100000000ULL;
add128(&remh, &reml, remh, reml, mh, ml);
}
remh = (remh << 32) | (reml >> 32);
if (mh << 32 <= remh) {
z |= 0xffffffff;
} else {
do_div(remh, mh);
z |= remh;
}
return z;
}
// Operations on unpacked elements
#define vfp_sign_negate(sign) (sign ^ 0x8000)
// Single-precision
struct vfp_single {
s16 exponent;
u16 sign;
u32 significand;
};
// VFP_SINGLE_MANTISSA_BITS - number of bits in the mantissa
// VFP_SINGLE_EXPONENT_BITS - number of bits in the exponent
// VFP_SINGLE_LOW_BITS - number of low bits in the unpacked significand
// which are not propagated to the float upon packing.
#define VFP_SINGLE_MANTISSA_BITS (23)
#define VFP_SINGLE_EXPONENT_BITS (8)
#define VFP_SINGLE_LOW_BITS (32 - VFP_SINGLE_MANTISSA_BITS - 2)
#define VFP_SINGLE_LOW_BITS_MASK ((1 << VFP_SINGLE_LOW_BITS) - 1)
// The bit in an unpacked float which indicates that it is a quiet NaN
#define VFP_SINGLE_SIGNIFICAND_QNAN (1 << (VFP_SINGLE_MANTISSA_BITS - 1 + VFP_SINGLE_LOW_BITS))
// Operations on packed single-precision numbers
#define vfp_single_packed_sign(v) ((v) & 0x80000000)
#define vfp_single_packed_negate(v) ((v) ^ 0x80000000)
#define vfp_single_packed_abs(v) ((v) & ~0x80000000)
#define vfp_single_packed_exponent(v) (((v) >> VFP_SINGLE_MANTISSA_BITS) & ((1 << VFP_SINGLE_EXPONENT_BITS) - 1))
#define vfp_single_packed_mantissa(v) ((v) & ((1 << VFP_SINGLE_MANTISSA_BITS) - 1))
enum : u32 {
VFP_NUMBER = (1 << 0),
VFP_ZERO = (1 << 1),
VFP_DENORMAL = (1 << 2),
VFP_INFINITY = (1 << 3),
VFP_NAN = (1 << 4),
VFP_NAN_SIGNAL = (1 << 5),
VFP_QNAN = (VFP_NAN),
VFP_SNAN = (VFP_NAN|VFP_NAN_SIGNAL)
};
static inline int vfp_single_type(vfp_single* s)
{
int type = VFP_NUMBER;
if (s->exponent == 255) {
if (s->significand == 0)
type = VFP_INFINITY;
else if (s->significand & VFP_SINGLE_SIGNIFICAND_QNAN)
type = VFP_QNAN;
else
type = VFP_SNAN;
} else if (s->exponent == 0) {
if (s->significand == 0)
type |= VFP_ZERO;
else
type |= VFP_DENORMAL;
}
return type;
}
// Unpack a single-precision float. Note that this returns the magnitude
// of the single-precision float mantissa with the 1. if necessary,
// aligned to bit 30.
static inline void vfp_single_unpack(vfp_single* s, s32 val, u32* fpscr)
{
s->sign = vfp_single_packed_sign(val) >> 16,
s->exponent = vfp_single_packed_exponent(val);
u32 significand = ((u32)val << (32 - VFP_SINGLE_MANTISSA_BITS)) >> 2;
if (s->exponent && s->exponent != 255)
significand |= 0x40000000;
s->significand = significand;
// If flush-to-zero mode is enabled, turn the denormal into zero.
// On a VFPv2 architecture, the sign of the zero is always positive.
if ((*fpscr & FPSCR_FLUSH_TO_ZERO) != 0 && (vfp_single_type(s) & VFP_DENORMAL) != 0) {
s->sign = 0;
s->exponent = 0;
s->significand = 0;
*fpscr |= FPSCR_IDC;
}
}
// Re-pack a single-precision float. This assumes that the float is
// already normalised such that the MSB is bit 30, _not_ bit 31.
static inline s32 vfp_single_pack(vfp_single* s)
{
u32 val = (s->sign << 16) +
(s->exponent << VFP_SINGLE_MANTISSA_BITS) +
(s->significand >> VFP_SINGLE_LOW_BITS);
return (s32)val;
}
u32 vfp_single_normaliseround(ARMul_State* state, int sd, vfp_single* vs, u32 fpscr, u32 exceptions, const char* func);
// Double-precision
struct vfp_double {
s16 exponent;
u16 sign;
u64 significand;
};
// VFP_REG_ZERO is a special register number for vfp_get_double
// which returns (double)0.0. This is useful for the compare with
// zero instructions.
#ifdef CONFIG_VFPv3
#define VFP_REG_ZERO 32
#else
#define VFP_REG_ZERO 16
#endif
#define VFP_DOUBLE_MANTISSA_BITS (52)
#define VFP_DOUBLE_EXPONENT_BITS (11)
#define VFP_DOUBLE_LOW_BITS (64 - VFP_DOUBLE_MANTISSA_BITS - 2)
#define VFP_DOUBLE_LOW_BITS_MASK ((1 << VFP_DOUBLE_LOW_BITS) - 1)
// The bit in an unpacked double which indicates that it is a quiet NaN
#define VFP_DOUBLE_SIGNIFICAND_QNAN (1ULL << (VFP_DOUBLE_MANTISSA_BITS - 1 + VFP_DOUBLE_LOW_BITS))
// Operations on packed single-precision numbers
#define vfp_double_packed_sign(v) ((v) & (1ULL << 63))
#define vfp_double_packed_negate(v) ((v) ^ (1ULL << 63))
#define vfp_double_packed_abs(v) ((v) & ~(1ULL << 63))
#define vfp_double_packed_exponent(v) (((v) >> VFP_DOUBLE_MANTISSA_BITS) & ((1 << VFP_DOUBLE_EXPONENT_BITS) - 1))
#define vfp_double_packed_mantissa(v) ((v) & ((1ULL << VFP_DOUBLE_MANTISSA_BITS) - 1))
static inline int vfp_double_type(vfp_double* s)
{
int type = VFP_NUMBER;
if (s->exponent == 2047) {
if (s->significand == 0)
type = VFP_INFINITY;
else if (s->significand & VFP_DOUBLE_SIGNIFICAND_QNAN)
type = VFP_QNAN;
else
type = VFP_SNAN;
} else if (s->exponent == 0) {
if (s->significand == 0)
type |= VFP_ZERO;
else
type |= VFP_DENORMAL;
}
return type;
}
// Unpack a double-precision float. Note that this returns the magnitude
// of the double-precision float mantissa with the 1. if necessary,
// aligned to bit 62.
static inline void vfp_double_unpack(vfp_double* s, s64 val, u32* fpscr)
{
s->sign = vfp_double_packed_sign(val) >> 48;
s->exponent = vfp_double_packed_exponent(val);
u64 significand = ((u64)val << (64 - VFP_DOUBLE_MANTISSA_BITS)) >> 2;
if (s->exponent && s->exponent != 2047)
significand |= (1ULL << 62);
s->significand = significand;
// If flush-to-zero mode is enabled, turn the denormal into zero.
// On a VFPv2 architecture, the sign of the zero is always positive.
if ((*fpscr & FPSCR_FLUSH_TO_ZERO) != 0 && (vfp_double_type(s) & VFP_DENORMAL) != 0) {
s->sign = 0;
s->exponent = 0;
s->significand = 0;
*fpscr |= FPSCR_IDC;
}
}
// Re-pack a double-precision float. This assumes that the float is
// already normalised such that the MSB is bit 30, _not_ bit 31.
static inline s64 vfp_double_pack(vfp_double* s)
{
u64 val = ((u64)s->sign << 48) +
((u64)s->exponent << VFP_DOUBLE_MANTISSA_BITS) +
(s->significand >> VFP_DOUBLE_LOW_BITS);
return (s64)val;
}
u32 vfp_estimate_sqrt_significand(u32 exponent, u32 significand);
// A special flag to tell the normalisation code not to normalise.
#define VFP_NAN_FLAG 0x100
// A bit pattern used to indicate the initial (unset) value of the
// exception mask, in case nothing handles an instruction. This
// doesn't include the NAN flag, which get masked out before
// we check for an error.
#define VFP_EXCEPTION_ERROR ((u32)-1 & ~VFP_NAN_FLAG)
// A flag to tell vfp instruction type.
// OP_SCALAR - This operation always operates in scalar mode
// OP_SD - The instruction exceptionally writes to a single precision result.
// OP_DD - The instruction exceptionally writes to a double precision result.
// OP_SM - The instruction exceptionally reads from a single precision operand.
enum : u32 {
OP_SCALAR = (1 << 0),
OP_SD = (1 << 1),
OP_DD = (1 << 1),
OP_SM = (1 << 2)
};
struct op {
u32 (* const fn)(ARMul_State* state, int dd, int dn, int dm, u32 fpscr);
u32 flags;
};
static inline u32 fls(ARMword x)
{
int r = 32;
if (!x)
return 0;
if (!(x & 0xffff0000u)) {
x <<= 16;
r -= 16;
}
if (!(x & 0xff000000u)) {
x <<= 8;
r -= 8;
}
if (!(x & 0xf0000000u)) {
x <<= 4;
r -= 4;
}
if (!(x & 0xc0000000u)) {
x <<= 2;
r -= 2;
}
if (!(x & 0x80000000u)) {
x <<= 1;
r -= 1;
}
return r;
}
u32 vfp_double_multiply(vfp_double* vdd, vfp_double* vdn, vfp_double* vdm, u32 fpscr);
u32 vfp_double_add(vfp_double* vdd, vfp_double* vdn, vfp_double *vdm, u32 fpscr);
u32 vfp_double_normaliseround(ARMul_State* state, int dd, vfp_double* vd, u32 fpscr, u32 exceptions, const char* func);