/*
* Copyright(c) 2019-2021 Qualcomm Innovation Center, Inc. All Rights Reserved.
*
* 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, see <http://www.gnu.org/licenses/>.
*/
#include "qemu/osdep.h"
#include "fpu/softfloat.h"
#include "cpu.h"
#include "fma_emu.h"
#include "arch.h"
#include "macros.h"
#define SF_BIAS 127
#define SF_MAXEXP 254
#define SF_MANTBITS 23
#define float32_nan make_float32(0xffffffff)
#define BITS_MASK_8 0x5555555555555555ULL
#define PAIR_MASK_8 0x3333333333333333ULL
#define NYBL_MASK_8 0x0f0f0f0f0f0f0f0fULL
#define BYTE_MASK_8 0x00ff00ff00ff00ffULL
#define HALF_MASK_8 0x0000ffff0000ffffULL
#define WORD_MASK_8 0x00000000ffffffffULL
uint64_t interleave(uint32_t odd, uint32_t even)
{
/* Convert to long long */
uint64_t myodd = odd;
uint64_t myeven = even;
/* First, spread bits out */
myodd = (myodd | (myodd << 16)) & HALF_MASK_8;
myeven = (myeven | (myeven << 16)) & HALF_MASK_8;
myodd = (myodd | (myodd << 8)) & BYTE_MASK_8;
myeven = (myeven | (myeven << 8)) & BYTE_MASK_8;
myodd = (myodd | (myodd << 4)) & NYBL_MASK_8;
myeven = (myeven | (myeven << 4)) & NYBL_MASK_8;
myodd = (myodd | (myodd << 2)) & PAIR_MASK_8;
myeven = (myeven | (myeven << 2)) & PAIR_MASK_8;
myodd = (myodd | (myodd << 1)) & BITS_MASK_8;
myeven = (myeven | (myeven << 1)) & BITS_MASK_8;
/* Now OR together */
return myeven | (myodd << 1);
}
uint64_t deinterleave(uint64_t src)
{
/* Get odd and even bits */
uint64_t myodd = ((src >> 1) & BITS_MASK_8);
uint64_t myeven = (src & BITS_MASK_8);
/* Unspread bits */
myeven = (myeven | (myeven >> 1)) & PAIR_MASK_8;
myodd = (myodd | (myodd >> 1)) & PAIR_MASK_8;
myeven = (myeven | (myeven >> 2)) & NYBL_MASK_8;
myodd = (myodd | (myodd >> 2)) & NYBL_MASK_8;
myeven = (myeven | (myeven >> 4)) & BYTE_MASK_8;
myodd = (myodd | (myodd >> 4)) & BYTE_MASK_8;
myeven = (myeven | (myeven >> 8)) & HALF_MASK_8;
myodd = (myodd | (myodd >> 8)) & HALF_MASK_8;
myeven = (myeven | (myeven >> 16)) & WORD_MASK_8;
myodd = (myodd | (myodd >> 16)) & WORD_MASK_8;
/* Return odd bits in upper half */
return myeven | (myodd << 32);
}
int32_t conv_round(int32_t a, int n)
{
int64_t val;
if (n == 0) {
val = a;
} else if ((a & ((1 << (n - 1)) - 1)) == 0) { /* N-1..0 all zero? */
/* Add LSB from int part */
val = ((fSE32_64(a)) + (int64_t) (((uint32_t) ((1 << n) & a)) >> 1));
} else {
val = ((fSE32_64(a)) + (1 << (n - 1)));
}
val = val >> n;
return (int32_t)val;
}
/* Floating Point Stuff */
static const int softfloat_roundingmodes[] = {
float_round_nearest_even,
float_round_to_zero,
float_round_down,
float_round_up,
};
void arch_fpop_start(CPUHexagonState *env)
{
set_float_exception_flags(0, &env->fp_status);
set_float_rounding_mode(
softfloat_roundingmodes[fREAD_REG_FIELD(USR, USR_FPRND)],
&env->fp_status);
}
#ifdef CONFIG_USER_ONLY
/*
* Hexagon Linux kernel only sets the relevant bits in USR (user status
* register). The exception isn't raised to user mode, so we don't
* model it in qemu user mode.
*/
#define RAISE_FP_EXCEPTION do {} while (0)
#endif
#define SOFTFLOAT_TEST_FLAG(FLAG, MYF, MYE) \
do { \
if (flags & FLAG) { \
if (GET_USR_FIELD(USR_##MYF) == 0) { \
SET_USR_FIELD(USR_##MYF, 1); \
if (GET_USR_FIELD(USR_##MYE)) { \
RAISE_FP_EXCEPTION; \
} \
} \
} \
} while (0)
void arch_fpop_end(CPUHexagonState *env)
{
int flags = get_float_exception_flags(&env->fp_status);
if (flags != 0) {
SOFTFLOAT_TEST_FLAG(float_flag_inexact, FPINPF, FPINPE);
SOFTFLOAT_TEST_FLAG(float_flag_divbyzero, FPDBZF, FPDBZE);
SOFTFLOAT_TEST_FLAG(float_flag_invalid, FPINVF, FPINVE);
SOFTFLOAT_TEST_FLAG(float_flag_overflow, FPOVFF, FPOVFE);
SOFTFLOAT_TEST_FLAG(float_flag_underflow, FPUNFF, FPUNFE);
}
}
static float32 float32_mul_pow2(float32 a, uint32_t p, float_status *fp_status)
{
float32 b = make_float32((SF_BIAS + p) << SF_MANTBITS);
return float32_mul(a, b, fp_status);
}
int arch_sf_recip_common(float32 *Rs, float32 *Rt, float32 *Rd, int *adjust,
float_status *fp_status)
{
int n_exp;
int d_exp;
int ret = 0;
float32 RsV, RtV, RdV;
int PeV = 0;
RsV = *Rs;
RtV = *Rt;
if (float32_is_any_nan(RsV) && float32_is_any_nan(RtV)) {
if (extract32(RsV & RtV, 22, 1) == 0) {
float_raise(float_flag_invalid, fp_status);
}
RdV = RsV = RtV = float32_nan;
} else if (float32_is_any_nan(RsV)) {
if (extract32(RsV, 22, 1) == 0) {
float_raise(float_flag_invalid, fp_status);
}
RdV = RsV = RtV = float32_nan;
} else if (float32_is_any_nan(RtV)) {
/* or put NaN in num/den fixup? */
if (extract32(RtV, 22, 1) == 0) {
float_raise(float_flag_invalid, fp_status);
}
RdV = RsV = RtV = float32_nan;
} else if (float32_is_infinity(RsV) && float32_is_infinity(RtV)) {
/* or put Inf in num fixup? */
RdV = RsV = RtV = float32_nan;
float_raise(float_flag_invalid, fp_status);
} else if (float32_is_zero(RsV) && float32_is_zero(RtV)) {
/* or put zero in num fixup? */
RdV = RsV = RtV = float32_nan;
float_raise(float_flag_invalid, fp_status);
} else if (float32_is_zero(RtV)) {
/* or put Inf in num fixup? */
uint8_t RsV_sign = float32_is_neg(RsV);
uint8_t RtV_sign = float32_is_neg(RtV);
RsV = infinite_float32(RsV_sign ^ RtV_sign);
RtV = float32_one;
RdV = float32_one;
if (float32_is_infinity(RsV)) {
float_raise(float_flag_divbyzero, fp_status);
}
} else if (float32_is_infinity(RtV)) {
RsV = make_float32(0x80000000 & (RsV ^ RtV));
RtV = float32_one;
RdV = float32_one;
} else if (float32_is_zero(RsV)) {
/* Does this just work itself out? */
/* No, 0/Inf causes problems. */
RsV = make_float32(0x80000000 & (RsV ^ RtV));
RtV = float32_one;
RdV = float32_one;
} else if (float32_is_infinity(RsV)) {
uint8_t RsV_sign = float32_is_neg(RsV);
uint8_t RtV_sign = float32_is_neg(RtV);
RsV = infinite_float32(RsV_sign ^ RtV_sign);
RtV = float32_one;
RdV = float32_one;
} else {
PeV = 0x00;
/* Basic checks passed */
n_exp = float32_getexp(RsV);
d_exp = float32_getexp(RtV);
if ((n_exp - d_exp + SF_BIAS) <= SF_MANTBITS) {
/* Near quotient underflow / inexact Q */
PeV = 0x80;
RtV = float32_mul_pow2(RtV, -64, fp_status);
RsV = float32_mul_pow2(RsV, 64, fp_status);
} else if ((n_exp - d_exp + SF_BIAS) > (SF_MAXEXP - 24)) {
/* Near quotient overflow */
PeV = 0x40;
RtV = float32_mul_pow2(RtV, 32, fp_status);
RsV = float32_mul_pow2(RsV, -32, fp_status);
} else if (n_exp <= SF_MANTBITS + 2) {
RtV = float32_mul_pow2(RtV, 64, fp_status);
RsV = float32_mul_pow2(RsV, 64, fp_status);
} else if (d_exp <= 1) {
RtV = float32_mul_pow2(RtV, 32, fp_status);
RsV = float32_mul_pow2(RsV, 32, fp_status);
} else if (d_exp > 252) {
RtV = float32_mul_pow2(RtV, -32, fp_status);
RsV = float32_mul_pow2(RsV, -32, fp_status);
}
RdV = 0;
ret = 1;
}
*Rs = RsV;
*Rt = RtV;
*Rd = RdV;
*adjust = PeV;
return ret;
}
int arch_sf_invsqrt_common(float32 *Rs, float32 *Rd, int *adjust,
float_status *fp_status)
{
float32 RsV, RdV;
int PeV = 0;
int r_exp;
int ret = 0;
RsV = *Rs;
if (float32_is_infinity(RsV)) {
if (extract32(RsV, 22, 1) == 0) {
float_raise(float_flag_invalid, fp_status);
}
RdV = RsV = float32_nan;
} else if (float32_lt(RsV, float32_zero, fp_status)) {
/* Negative nonzero values are NaN */
float_raise(float_flag_invalid, fp_status);
RsV = float32_nan;
RdV = float32_nan;
} else if (float32_is_infinity(RsV)) {
/* or put Inf in num fixup? */
RsV = infinite_float32(1);
RdV = infinite_float32(1);
} else if (float32_is_zero(RsV)) {
/* or put zero in num fixup? */
RdV = float32_one;
} else {
PeV = 0x00;
/* Basic checks passed */
r_exp = float32_getexp(RsV);
if (r_exp <= 24) {
RsV = float32_mul_pow2(RsV, 64, fp_status);
PeV = 0xe0;
}
RdV = 0;
ret = 1;
}
*Rs = RsV;
*Rd = RdV;
*adjust = PeV;
return ret;
}
