qemu-e2k/target-ppc/dfp_helper.c

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/*
* PowerPC Decimal Floating Point (DPF) emulation helpers for QEMU.
*
* Copyright (c) 2014 IBM Corporation.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include "cpu.h"
#include "exec/helper-proto.h"
#define DECNUMDIGITS 34
#include "libdecnumber/decContext.h"
#include "libdecnumber/decNumber.h"
#include "libdecnumber/dpd/decimal32.h"
#include "libdecnumber/dpd/decimal64.h"
#include "libdecnumber/dpd/decimal128.h"
#if defined(HOST_WORDS_BIGENDIAN)
#define HI_IDX 0
#define LO_IDX 1
#else
#define HI_IDX 1
#define LO_IDX 0
#endif
struct PPC_DFP {
CPUPPCState *env;
uint64_t t64[2], a64[2], b64[2];
decNumber t, a, b;
decContext context;
uint8_t crbf;
};
static void dfp_prepare_rounding_mode(decContext *context, uint64_t fpscr)
{
enum rounding rnd;
switch ((fpscr >> 32) & 0x7) {
case 0:
rnd = DEC_ROUND_HALF_EVEN;
break;
case 1:
rnd = DEC_ROUND_DOWN;
break;
case 2:
rnd = DEC_ROUND_CEILING;
break;
case 3:
rnd = DEC_ROUND_FLOOR;
break;
case 4:
rnd = DEC_ROUND_HALF_UP;
break;
case 5:
rnd = DEC_ROUND_HALF_DOWN;
break;
case 6:
rnd = DEC_ROUND_UP;
break;
case 7:
rnd = DEC_ROUND_05UP;
break;
default:
g_assert_not_reached();
}
decContextSetRounding(context, rnd);
}
static void dfp_set_round_mode_from_immediate(uint8_t r, uint8_t rmc,
struct PPC_DFP *dfp)
{
enum rounding rnd;
if (r == 0) {
switch (rmc & 3) {
case 0:
rnd = DEC_ROUND_HALF_EVEN;
break;
case 1:
rnd = DEC_ROUND_DOWN;
break;
case 2:
rnd = DEC_ROUND_HALF_UP;
break;
case 3: /* use FPSCR rounding mode */
return;
default:
assert(0); /* cannot get here */
}
} else { /* r == 1 */
switch (rmc & 3) {
case 0:
rnd = DEC_ROUND_CEILING;
break;
case 1:
rnd = DEC_ROUND_FLOOR;
break;
case 2:
rnd = DEC_ROUND_UP;
break;
case 3:
rnd = DEC_ROUND_HALF_DOWN;
break;
default:
assert(0); /* cannot get here */
}
}
decContextSetRounding(&dfp->context, rnd);
}
static void dfp_prepare_decimal64(struct PPC_DFP *dfp, uint64_t *a,
uint64_t *b, CPUPPCState *env)
{
decContextDefault(&dfp->context, DEC_INIT_DECIMAL64);
dfp_prepare_rounding_mode(&dfp->context, env->fpscr);
dfp->env = env;
if (a) {
dfp->a64[0] = *a;
decimal64ToNumber((decimal64 *)dfp->a64, &dfp->a);
} else {
dfp->a64[0] = 0;
decNumberZero(&dfp->a);
}
if (b) {
dfp->b64[0] = *b;
decimal64ToNumber((decimal64 *)dfp->b64, &dfp->b);
} else {
dfp->b64[0] = 0;
decNumberZero(&dfp->b);
}
}
static void dfp_prepare_decimal128(struct PPC_DFP *dfp, uint64_t *a,
uint64_t *b, CPUPPCState *env)
{
decContextDefault(&dfp->context, DEC_INIT_DECIMAL128);
dfp_prepare_rounding_mode(&dfp->context, env->fpscr);
dfp->env = env;
if (a) {
dfp->a64[0] = a[HI_IDX];
dfp->a64[1] = a[LO_IDX];
decimal128ToNumber((decimal128 *)dfp->a64, &dfp->a);
} else {
dfp->a64[0] = dfp->a64[1] = 0;
decNumberZero(&dfp->a);
}
if (b) {
dfp->b64[0] = b[HI_IDX];
dfp->b64[1] = b[LO_IDX];
decimal128ToNumber((decimal128 *)dfp->b64, &dfp->b);
} else {
dfp->b64[0] = dfp->b64[1] = 0;
decNumberZero(&dfp->b);
}
}
#define FP_FX (1ull << FPSCR_FX)
#define FP_FEX (1ull << FPSCR_FEX)
#define FP_OX (1ull << FPSCR_OX)
#define FP_OE (1ull << FPSCR_OE)
#define FP_UX (1ull << FPSCR_UX)
#define FP_UE (1ull << FPSCR_UE)
#define FP_XX (1ull << FPSCR_XX)
#define FP_XE (1ull << FPSCR_XE)
#define FP_ZX (1ull << FPSCR_ZX)
#define FP_ZE (1ull << FPSCR_ZE)
#define FP_VX (1ull << FPSCR_VX)
#define FP_VXSNAN (1ull << FPSCR_VXSNAN)
#define FP_VXISI (1ull << FPSCR_VXISI)
#define FP_VXIMZ (1ull << FPSCR_VXIMZ)
#define FP_VXZDZ (1ull << FPSCR_VXZDZ)
#define FP_VXIDI (1ull << FPSCR_VXIDI)
#define FP_VXVC (1ull << FPSCR_VXVC)
#define FP_VXCVI (1ull << FPSCR_VXCVI)
#define FP_VE (1ull << FPSCR_VE)
#define FP_FI (1ull << FPSCR_FI)
static void dfp_set_FPSCR_flag(struct PPC_DFP *dfp, uint64_t flag,
uint64_t enabled)
{
dfp->env->fpscr |= (flag | FP_FX);
if (dfp->env->fpscr & enabled) {
dfp->env->fpscr |= FP_FEX;
}
}
static void dfp_set_FPRF_from_FRT_with_context(struct PPC_DFP *dfp,
decContext *context)
{
uint64_t fprf = 0;
/* construct FPRF */
switch (decNumberClass(&dfp->t, context)) {
case DEC_CLASS_SNAN:
fprf = 0x01;
break;
case DEC_CLASS_QNAN:
fprf = 0x11;
break;
case DEC_CLASS_NEG_INF:
fprf = 0x09;
break;
case DEC_CLASS_NEG_NORMAL:
fprf = 0x08;
break;
case DEC_CLASS_NEG_SUBNORMAL:
fprf = 0x18;
break;
case DEC_CLASS_NEG_ZERO:
fprf = 0x12;
break;
case DEC_CLASS_POS_ZERO:
fprf = 0x02;
break;
case DEC_CLASS_POS_SUBNORMAL:
fprf = 0x14;
break;
case DEC_CLASS_POS_NORMAL:
fprf = 0x04;
break;
case DEC_CLASS_POS_INF:
fprf = 0x05;
break;
default:
assert(0); /* should never get here */
}
dfp->env->fpscr &= ~(0x1F << 12);
dfp->env->fpscr |= (fprf << 12);
}
static void dfp_set_FPRF_from_FRT(struct PPC_DFP *dfp)
{
dfp_set_FPRF_from_FRT_with_context(dfp, &dfp->context);
}
static void dfp_set_FPRF_from_FRT_short(struct PPC_DFP *dfp)
{
decContext shortContext;
decContextDefault(&shortContext, DEC_INIT_DECIMAL32);
dfp_set_FPRF_from_FRT_with_context(dfp, &shortContext);
}
static void dfp_set_FPRF_from_FRT_long(struct PPC_DFP *dfp)
{
decContext longContext;
decContextDefault(&longContext, DEC_INIT_DECIMAL64);
dfp_set_FPRF_from_FRT_with_context(dfp, &longContext);
}
static void dfp_check_for_OX(struct PPC_DFP *dfp)
{
if (dfp->context.status & DEC_Overflow) {
dfp_set_FPSCR_flag(dfp, FP_OX, FP_OE);
}
}
static void dfp_check_for_UX(struct PPC_DFP *dfp)
{
if (dfp->context.status & DEC_Underflow) {
dfp_set_FPSCR_flag(dfp, FP_UX, FP_UE);
}
}
static void dfp_check_for_XX(struct PPC_DFP *dfp)
{
if (dfp->context.status & DEC_Inexact) {
dfp_set_FPSCR_flag(dfp, FP_XX | FP_FI, FP_XE);
}
}
static void dfp_check_for_ZX(struct PPC_DFP *dfp)
{
if (dfp->context.status & DEC_Division_by_zero) {
dfp_set_FPSCR_flag(dfp, FP_ZX, FP_ZE);
}
}
static void dfp_check_for_VXSNAN(struct PPC_DFP *dfp)
{
if (dfp->context.status & DEC_Invalid_operation) {
if (decNumberIsSNaN(&dfp->a) || decNumberIsSNaN(&dfp->b)) {
dfp_set_FPSCR_flag(dfp, FP_VX | FP_VXSNAN, FP_VE);
}
}
}
static void dfp_check_for_VXSNAN_and_convert_to_QNaN(struct PPC_DFP *dfp)
{
if (decNumberIsSNaN(&dfp->t)) {
dfp->t.bits &= ~DECSNAN;
dfp->t.bits |= DECNAN;
dfp_set_FPSCR_flag(dfp, FP_VX | FP_VXSNAN, FP_VE);
}
}
static void dfp_check_for_VXISI(struct PPC_DFP *dfp, int testForSameSign)
{
if (dfp->context.status & DEC_Invalid_operation) {
if (decNumberIsInfinite(&dfp->a) && decNumberIsInfinite(&dfp->b)) {
int same = decNumberClass(&dfp->a, &dfp->context) ==
decNumberClass(&dfp->b, &dfp->context);
if ((same && testForSameSign) || (!same && !testForSameSign)) {
dfp_set_FPSCR_flag(dfp, FP_VX | FP_VXISI, FP_VE);
}
}
}
}
static void dfp_check_for_VXISI_add(struct PPC_DFP *dfp)
{
dfp_check_for_VXISI(dfp, 0);
}
static void dfp_check_for_VXISI_subtract(struct PPC_DFP *dfp)
{
dfp_check_for_VXISI(dfp, 1);
}
static void dfp_check_for_VXIMZ(struct PPC_DFP *dfp)
{
if (dfp->context.status & DEC_Invalid_operation) {
if ((decNumberIsInfinite(&dfp->a) && decNumberIsZero(&dfp->b)) ||
(decNumberIsInfinite(&dfp->b) && decNumberIsZero(&dfp->a))) {
dfp_set_FPSCR_flag(dfp, FP_VX | FP_VXIMZ, FP_VE);
}
}
}
static void dfp_check_for_VXZDZ(struct PPC_DFP *dfp)
{
if (dfp->context.status & DEC_Division_undefined) {
dfp_set_FPSCR_flag(dfp, FP_VX | FP_VXZDZ, FP_VE);
}
}
static void dfp_check_for_VXIDI(struct PPC_DFP *dfp)
{
if (dfp->context.status & DEC_Invalid_operation) {
if (decNumberIsInfinite(&dfp->a) && decNumberIsInfinite(&dfp->b)) {
dfp_set_FPSCR_flag(dfp, FP_VX | FP_VXIDI, FP_VE);
}
}
}
static void dfp_check_for_VXVC(struct PPC_DFP *dfp)
{
if (decNumberIsNaN(&dfp->a) || decNumberIsNaN(&dfp->b)) {
dfp_set_FPSCR_flag(dfp, FP_VX | FP_VXVC, FP_VE);
}
}
static void dfp_check_for_VXCVI(struct PPC_DFP *dfp)
{
if ((dfp->context.status & DEC_Invalid_operation) &&
(!decNumberIsSNaN(&dfp->a)) &&
(!decNumberIsSNaN(&dfp->b))) {
dfp_set_FPSCR_flag(dfp, FP_VX | FP_VXCVI, FP_VE);
}
}
static void dfp_set_CRBF_from_T(struct PPC_DFP *dfp)
{
if (decNumberIsNaN(&dfp->t)) {
dfp->crbf = 1;
} else if (decNumberIsZero(&dfp->t)) {
dfp->crbf = 2;
} else if (decNumberIsNegative(&dfp->t)) {
dfp->crbf = 8;
} else {
dfp->crbf = 4;
}
}
static void dfp_set_FPCC_from_CRBF(struct PPC_DFP *dfp)
{
dfp->env->fpscr &= ~(0xF << 12);
dfp->env->fpscr |= (dfp->crbf << 12);
}
static inline void dfp_makeQNaN(decNumber *dn)
{
dn->bits &= ~DECSPECIAL;
dn->bits |= DECNAN;
}
static inline int dfp_get_digit(decNumber *dn, int n)
{
assert(DECDPUN == 3);
int unit = n / DECDPUN;
int dig = n % DECDPUN;
switch (dig) {
case 0:
return dn->lsu[unit] % 10;
case 1:
return (dn->lsu[unit] / 10) % 10;
case 2:
return dn->lsu[unit] / 100;
default:
assert(0);
}
}
#define DFP_HELPER_TAB(op, dnop, postprocs, size) \
void helper_##op(CPUPPCState *env, uint64_t *t, uint64_t *a, uint64_t *b) \
{ \
struct PPC_DFP dfp; \
dfp_prepare_decimal##size(&dfp, a, b, env); \
dnop(&dfp.t, &dfp.a, &dfp.b, &dfp.context); \
decimal##size##FromNumber((decimal##size *)dfp.t64, &dfp.t, &dfp.context); \
postprocs(&dfp); \
if (size == 64) { \
t[0] = dfp.t64[0]; \
} else if (size == 128) { \
t[0] = dfp.t64[HI_IDX]; \
t[1] = dfp.t64[LO_IDX]; \
} \
}
static void ADD_PPs(struct PPC_DFP *dfp)
{
dfp_set_FPRF_from_FRT(dfp);
dfp_check_for_OX(dfp);
dfp_check_for_UX(dfp);
dfp_check_for_XX(dfp);
dfp_check_for_VXSNAN(dfp);
dfp_check_for_VXISI_add(dfp);
}
DFP_HELPER_TAB(dadd, decNumberAdd, ADD_PPs, 64)
DFP_HELPER_TAB(daddq, decNumberAdd, ADD_PPs, 128)
static void SUB_PPs(struct PPC_DFP *dfp)
{
dfp_set_FPRF_from_FRT(dfp);
dfp_check_for_OX(dfp);
dfp_check_for_UX(dfp);
dfp_check_for_XX(dfp);
dfp_check_for_VXSNAN(dfp);
dfp_check_for_VXISI_subtract(dfp);
}
DFP_HELPER_TAB(dsub, decNumberSubtract, SUB_PPs, 64)
DFP_HELPER_TAB(dsubq, decNumberSubtract, SUB_PPs, 128)
static void MUL_PPs(struct PPC_DFP *dfp)
{
dfp_set_FPRF_from_FRT(dfp);
dfp_check_for_OX(dfp);
dfp_check_for_UX(dfp);
dfp_check_for_XX(dfp);
dfp_check_for_VXSNAN(dfp);
dfp_check_for_VXIMZ(dfp);
}
DFP_HELPER_TAB(dmul, decNumberMultiply, MUL_PPs, 64)
DFP_HELPER_TAB(dmulq, decNumberMultiply, MUL_PPs, 128)
static void DIV_PPs(struct PPC_DFP *dfp)
{
dfp_set_FPRF_from_FRT(dfp);
dfp_check_for_OX(dfp);
dfp_check_for_UX(dfp);
dfp_check_for_ZX(dfp);
dfp_check_for_XX(dfp);
dfp_check_for_VXSNAN(dfp);
dfp_check_for_VXZDZ(dfp);
dfp_check_for_VXIDI(dfp);
}
DFP_HELPER_TAB(ddiv, decNumberDivide, DIV_PPs, 64)
DFP_HELPER_TAB(ddivq, decNumberDivide, DIV_PPs, 128)
#define DFP_HELPER_BF_AB(op, dnop, postprocs, size) \
uint32_t helper_##op(CPUPPCState *env, uint64_t *a, uint64_t *b) \
{ \
struct PPC_DFP dfp; \
dfp_prepare_decimal##size(&dfp, a, b, env); \
dnop(&dfp.t, &dfp.a, &dfp.b, &dfp.context); \
decimal##size##FromNumber((decimal##size *)dfp.t64, &dfp.t, &dfp.context); \
postprocs(&dfp); \
return dfp.crbf; \
}
static void CMPU_PPs(struct PPC_DFP *dfp)
{
dfp_set_CRBF_from_T(dfp);
dfp_set_FPCC_from_CRBF(dfp);
dfp_check_for_VXSNAN(dfp);
}
DFP_HELPER_BF_AB(dcmpu, decNumberCompare, CMPU_PPs, 64)
DFP_HELPER_BF_AB(dcmpuq, decNumberCompare, CMPU_PPs, 128)
static void CMPO_PPs(struct PPC_DFP *dfp)
{
dfp_set_CRBF_from_T(dfp);
dfp_set_FPCC_from_CRBF(dfp);
dfp_check_for_VXSNAN(dfp);
dfp_check_for_VXVC(dfp);
}
DFP_HELPER_BF_AB(dcmpo, decNumberCompare, CMPO_PPs, 64)
DFP_HELPER_BF_AB(dcmpoq, decNumberCompare, CMPO_PPs, 128)
#define DFP_HELPER_TSTDC(op, size) \
uint32_t helper_##op(CPUPPCState *env, uint64_t *a, uint32_t dcm) \
{ \
struct PPC_DFP dfp; \
int match = 0; \
\
dfp_prepare_decimal##size(&dfp, a, 0, env); \
\
match |= (dcm & 0x20) && decNumberIsZero(&dfp.a); \
match |= (dcm & 0x10) && decNumberIsSubnormal(&dfp.a, &dfp.context); \
match |= (dcm & 0x08) && decNumberIsNormal(&dfp.a, &dfp.context); \
match |= (dcm & 0x04) && decNumberIsInfinite(&dfp.a); \
match |= (dcm & 0x02) && decNumberIsQNaN(&dfp.a); \
match |= (dcm & 0x01) && decNumberIsSNaN(&dfp.a); \
\
if (decNumberIsNegative(&dfp.a)) { \
dfp.crbf = match ? 0xA : 0x8; \
} else { \
dfp.crbf = match ? 0x2 : 0x0; \
} \
\
dfp_set_FPCC_from_CRBF(&dfp); \
return dfp.crbf; \
}
DFP_HELPER_TSTDC(dtstdc, 64)
DFP_HELPER_TSTDC(dtstdcq, 128)
#define DFP_HELPER_TSTDG(op, size) \
uint32_t helper_##op(CPUPPCState *env, uint64_t *a, uint32_t dcm) \
{ \
struct PPC_DFP dfp; \
int minexp, maxexp, nzero_digits, nzero_idx, is_negative, is_zero, \
is_extreme_exp, is_subnormal, is_normal, leftmost_is_nonzero, \
match; \
\
dfp_prepare_decimal##size(&dfp, a, 0, env); \
\
if ((size) == 64) { \
minexp = -398; \
maxexp = 369; \
nzero_digits = 16; \
nzero_idx = 5; \
} else if ((size) == 128) { \
minexp = -6176; \
maxexp = 6111; \
nzero_digits = 34; \
nzero_idx = 11; \
} \
\
is_negative = decNumberIsNegative(&dfp.a); \
is_zero = decNumberIsZero(&dfp.a); \
is_extreme_exp = (dfp.a.exponent == maxexp) || \
(dfp.a.exponent == minexp); \
is_subnormal = decNumberIsSubnormal(&dfp.a, &dfp.context); \
is_normal = decNumberIsNormal(&dfp.a, &dfp.context); \
leftmost_is_nonzero = (dfp.a.digits == nzero_digits) && \
(dfp.a.lsu[nzero_idx] != 0); \
match = 0; \
\
match |= (dcm & 0x20) && is_zero && !is_extreme_exp; \
match |= (dcm & 0x10) && is_zero && is_extreme_exp; \
match |= (dcm & 0x08) && \
(is_subnormal || (is_normal && is_extreme_exp)); \
match |= (dcm & 0x04) && is_normal && !is_extreme_exp && \
!leftmost_is_nonzero; \
match |= (dcm & 0x02) && is_normal && !is_extreme_exp && \
leftmost_is_nonzero; \
match |= (dcm & 0x01) && decNumberIsSpecial(&dfp.a); \
\
if (is_negative) { \
dfp.crbf = match ? 0xA : 0x8; \
} else { \
dfp.crbf = match ? 0x2 : 0x0; \
} \
\
dfp_set_FPCC_from_CRBF(&dfp); \
return dfp.crbf; \
}
DFP_HELPER_TSTDG(dtstdg, 64)
DFP_HELPER_TSTDG(dtstdgq, 128)
#define DFP_HELPER_TSTEX(op, size) \
uint32_t helper_##op(CPUPPCState *env, uint64_t *a, uint64_t *b) \
{ \
struct PPC_DFP dfp; \
int expa, expb, a_is_special, b_is_special; \
\
dfp_prepare_decimal##size(&dfp, a, b, env); \
\
expa = dfp.a.exponent; \
expb = dfp.b.exponent; \
a_is_special = decNumberIsSpecial(&dfp.a); \
b_is_special = decNumberIsSpecial(&dfp.b); \
\
if (a_is_special || b_is_special) { \
int atype = a_is_special ? (decNumberIsNaN(&dfp.a) ? 4 : 2) : 1; \
int btype = b_is_special ? (decNumberIsNaN(&dfp.b) ? 4 : 2) : 1; \
dfp.crbf = (atype ^ btype) ? 0x1 : 0x2; \
} else if (expa < expb) { \
dfp.crbf = 0x8; \
} else if (expa > expb) { \
dfp.crbf = 0x4; \
} else { \
dfp.crbf = 0x2; \
} \
\
dfp_set_FPCC_from_CRBF(&dfp); \
return dfp.crbf; \
}
DFP_HELPER_TSTEX(dtstex, 64)
DFP_HELPER_TSTEX(dtstexq, 128)
#define DFP_HELPER_TSTSF(op, size) \
uint32_t helper_##op(CPUPPCState *env, uint64_t *a, uint64_t *b) \
{ \
struct PPC_DFP dfp; \
unsigned k; \
\
dfp_prepare_decimal##size(&dfp, 0, b, env); \
\
k = *a & 0x3F; \
\
if (unlikely(decNumberIsSpecial(&dfp.b))) { \
dfp.crbf = 1; \
} else if (k == 0) { \
dfp.crbf = 4; \
} else if (unlikely(decNumberIsZero(&dfp.b))) { \
/* Zero has no sig digits */ \
dfp.crbf = 4; \
} else { \
unsigned nsd = dfp.b.digits; \
if (k < nsd) { \
dfp.crbf = 8; \
} else if (k > nsd) { \
dfp.crbf = 4; \
} else { \
dfp.crbf = 2; \
} \
} \
\
dfp_set_FPCC_from_CRBF(&dfp); \
return dfp.crbf; \
}
DFP_HELPER_TSTSF(dtstsf, 64)
DFP_HELPER_TSTSF(dtstsfq, 128)
static void QUA_PPs(struct PPC_DFP *dfp)
{
dfp_set_FPRF_from_FRT(dfp);
dfp_check_for_XX(dfp);
dfp_check_for_VXSNAN(dfp);
dfp_check_for_VXCVI(dfp);
}
static void dfp_quantize(uint8_t rmc, struct PPC_DFP *dfp)
{
dfp_set_round_mode_from_immediate(0, rmc, dfp);
decNumberQuantize(&dfp->t, &dfp->b, &dfp->a, &dfp->context);
if (decNumberIsSNaN(&dfp->a)) {
dfp->t = dfp->a;
dfp_makeQNaN(&dfp->t);
} else if (decNumberIsSNaN(&dfp->b)) {
dfp->t = dfp->b;
dfp_makeQNaN(&dfp->t);
} else if (decNumberIsQNaN(&dfp->a)) {
dfp->t = dfp->a;
} else if (decNumberIsQNaN(&dfp->b)) {
dfp->t = dfp->b;
}
}
#define DFP_HELPER_QUAI(op, size) \
void helper_##op(CPUPPCState *env, uint64_t *t, uint64_t *b, \
uint32_t te, uint32_t rmc) \
{ \
struct PPC_DFP dfp; \
\
dfp_prepare_decimal##size(&dfp, 0, b, env); \
\
decNumberFromUInt32(&dfp.a, 1); \
dfp.a.exponent = (int32_t)((int8_t)(te << 3) >> 3); \
\
dfp_quantize(rmc, &dfp); \
decimal##size##FromNumber((decimal##size *)dfp.t64, &dfp.t, \
&dfp.context); \
QUA_PPs(&dfp); \
\
if (size == 64) { \
t[0] = dfp.t64[0]; \
} else if (size == 128) { \
t[0] = dfp.t64[HI_IDX]; \
t[1] = dfp.t64[LO_IDX]; \
} \
}
DFP_HELPER_QUAI(dquai, 64)
DFP_HELPER_QUAI(dquaiq, 128)
#define DFP_HELPER_QUA(op, size) \
void helper_##op(CPUPPCState *env, uint64_t *t, uint64_t *a, \
uint64_t *b, uint32_t rmc) \
{ \
struct PPC_DFP dfp; \
\
dfp_prepare_decimal##size(&dfp, a, b, env); \
\
dfp_quantize(rmc, &dfp); \
decimal##size##FromNumber((decimal##size *)dfp.t64, &dfp.t, \
&dfp.context); \
QUA_PPs(&dfp); \
\
if (size == 64) { \
t[0] = dfp.t64[0]; \
} else if (size == 128) { \
t[0] = dfp.t64[HI_IDX]; \
t[1] = dfp.t64[LO_IDX]; \
} \
}
DFP_HELPER_QUA(dqua, 64)
DFP_HELPER_QUA(dquaq, 128)
static void _dfp_reround(uint8_t rmc, int32_t ref_sig, int32_t xmax,
struct PPC_DFP *dfp)
{
int msd_orig, msd_rslt;
if (unlikely((ref_sig == 0) || (dfp->b.digits <= ref_sig))) {
dfp->t = dfp->b;
if (decNumberIsSNaN(&dfp->b)) {
dfp_makeQNaN(&dfp->t);
dfp_set_FPSCR_flag(dfp, FP_VX | FP_VXSNAN, FPSCR_VE);
}
return;
}
/* Reround is equivalent to quantizing b with 1**E(n) where */
/* n = exp(b) + numDigits(b) - reference_significance. */
decNumberFromUInt32(&dfp->a, 1);
dfp->a.exponent = dfp->b.exponent + dfp->b.digits - ref_sig;
if (unlikely(dfp->a.exponent > xmax)) {
dfp->t.digits = 0;
dfp->t.bits &= ~DECNEG;
dfp_makeQNaN(&dfp->t);
dfp_set_FPSCR_flag(dfp, FP_VX | FP_VXCVI, FPSCR_VE);
return;
}
dfp_quantize(rmc, dfp);
msd_orig = dfp_get_digit(&dfp->b, dfp->b.digits-1);
msd_rslt = dfp_get_digit(&dfp->t, dfp->t.digits-1);
/* If the quantization resulted in rounding up to the next magnitude, */
/* then we need to shift the significand and adjust the exponent. */
if (unlikely((msd_orig == 9) && (msd_rslt == 1))) {
decNumber negone;
decNumberFromInt32(&negone, -1);
decNumberShift(&dfp->t, &dfp->t, &negone, &dfp->context);
dfp->t.exponent++;
if (unlikely(dfp->t.exponent > xmax)) {
dfp_makeQNaN(&dfp->t);
dfp->t.digits = 0;
dfp_set_FPSCR_flag(dfp, FP_VX | FP_VXCVI, FP_VE);
/* Inhibit XX in this case */
decContextClearStatus(&dfp->context, DEC_Inexact);
}
}
}
#define DFP_HELPER_RRND(op, size) \
void helper_##op(CPUPPCState *env, uint64_t *t, uint64_t *a, \
uint64_t *b, uint32_t rmc) \
{ \
struct PPC_DFP dfp; \
int32_t ref_sig = *a & 0x3F; \
int32_t xmax = ((size) == 64) ? 369 : 6111; \
\
dfp_prepare_decimal##size(&dfp, 0, b, env); \
\
_dfp_reround(rmc, ref_sig, xmax, &dfp); \
decimal##size##FromNumber((decimal##size *)dfp.t64, &dfp.t, \
&dfp.context); \
QUA_PPs(&dfp); \
\
if (size == 64) { \
t[0] = dfp.t64[0]; \
} else if (size == 128) { \
t[0] = dfp.t64[HI_IDX]; \
t[1] = dfp.t64[LO_IDX]; \
} \
}
DFP_HELPER_RRND(drrnd, 64)
DFP_HELPER_RRND(drrndq, 128)
#define DFP_HELPER_RINT(op, postprocs, size) \
void helper_##op(CPUPPCState *env, uint64_t *t, uint64_t *b, \
uint32_t r, uint32_t rmc) \
{ \
struct PPC_DFP dfp; \
\
dfp_prepare_decimal##size(&dfp, 0, b, env); \
\
dfp_set_round_mode_from_immediate(r, rmc, &dfp); \
decNumberToIntegralExact(&dfp.t, &dfp.b, &dfp.context); \
decimal##size##FromNumber((decimal##size *)dfp.t64, &dfp.t, &dfp.context); \
postprocs(&dfp); \
\
if (size == 64) { \
t[0] = dfp.t64[0]; \
} else if (size == 128) { \
t[0] = dfp.t64[HI_IDX]; \
t[1] = dfp.t64[LO_IDX]; \
} \
}
static void RINTX_PPs(struct PPC_DFP *dfp)
{
dfp_set_FPRF_from_FRT(dfp);
dfp_check_for_XX(dfp);
dfp_check_for_VXSNAN(dfp);
}
DFP_HELPER_RINT(drintx, RINTX_PPs, 64)
DFP_HELPER_RINT(drintxq, RINTX_PPs, 128)
static void RINTN_PPs(struct PPC_DFP *dfp)
{
dfp_set_FPRF_from_FRT(dfp);
dfp_check_for_VXSNAN(dfp);
}
DFP_HELPER_RINT(drintn, RINTN_PPs, 64)
DFP_HELPER_RINT(drintnq, RINTN_PPs, 128)
void helper_dctdp(CPUPPCState *env, uint64_t *t, uint64_t *b)
{
struct PPC_DFP dfp;
uint32_t b_short = *b;
dfp_prepare_decimal64(&dfp, 0, 0, env);
decimal32ToNumber((decimal32 *)&b_short, &dfp.t);
decimal64FromNumber((decimal64 *)t, &dfp.t, &dfp.context);
dfp_set_FPRF_from_FRT(&dfp);
}
void helper_dctqpq(CPUPPCState *env, uint64_t *t, uint64_t *b)
{
struct PPC_DFP dfp;
dfp_prepare_decimal128(&dfp, 0, 0, env);
decimal64ToNumber((decimal64 *)b, &dfp.t);
dfp_check_for_VXSNAN_and_convert_to_QNaN(&dfp);
dfp_set_FPRF_from_FRT(&dfp);
decimal128FromNumber((decimal128 *)&dfp.t64, &dfp.t, &dfp.context);
t[0] = dfp.t64[HI_IDX];
t[1] = dfp.t64[LO_IDX];
}
void helper_drsp(CPUPPCState *env, uint64_t *t, uint64_t *b)
{
struct PPC_DFP dfp;
uint32_t t_short = 0;
dfp_prepare_decimal64(&dfp, 0, b, env);
decimal32FromNumber((decimal32 *)&t_short, &dfp.b, &dfp.context);
decimal32ToNumber((decimal32 *)&t_short, &dfp.t);
dfp_set_FPRF_from_FRT_short(&dfp);
dfp_check_for_OX(&dfp);
dfp_check_for_UX(&dfp);
dfp_check_for_XX(&dfp);
*t = t_short;
}
void helper_drdpq(CPUPPCState *env, uint64_t *t, uint64_t *b)
{
struct PPC_DFP dfp;
dfp_prepare_decimal128(&dfp, 0, b, env);
decimal64FromNumber((decimal64 *)&dfp.t64, &dfp.b, &dfp.context);
decimal64ToNumber((decimal64 *)&dfp.t64, &dfp.t);
dfp_check_for_VXSNAN_and_convert_to_QNaN(&dfp);
dfp_set_FPRF_from_FRT_long(&dfp);
dfp_check_for_OX(&dfp);
dfp_check_for_UX(&dfp);
dfp_check_for_XX(&dfp);
decimal64FromNumber((decimal64 *)dfp.t64, &dfp.t, &dfp.context);
t[0] = dfp.t64[0];
t[1] = 0;
}
#define DFP_HELPER_CFFIX(op, size) \
void helper_##op(CPUPPCState *env, uint64_t *t, uint64_t *b) \
{ \
struct PPC_DFP dfp; \
dfp_prepare_decimal##size(&dfp, 0, b, env); \
decNumberFromInt64(&dfp.t, (int64_t)(*b)); \
decimal##size##FromNumber((decimal##size *)dfp.t64, &dfp.t, &dfp.context); \
CFFIX_PPs(&dfp); \
\
if (size == 64) { \
t[0] = dfp.t64[0]; \
} else if (size == 128) { \
t[0] = dfp.t64[HI_IDX]; \
t[1] = dfp.t64[LO_IDX]; \
} \
}
static void CFFIX_PPs(struct PPC_DFP *dfp)
{
dfp_set_FPRF_from_FRT(dfp);
dfp_check_for_XX(dfp);
}
DFP_HELPER_CFFIX(dcffix, 64)
DFP_HELPER_CFFIX(dcffixq, 128)
#define DFP_HELPER_CTFIX(op, size) \
void helper_##op(CPUPPCState *env, uint64_t *t, uint64_t *b) \
{ \
struct PPC_DFP dfp; \
dfp_prepare_decimal##size(&dfp, 0, b, env); \
\
if (unlikely(decNumberIsSpecial(&dfp.b))) { \
uint64_t invalid_flags = FP_VX | FP_VXCVI; \
if (decNumberIsInfinite(&dfp.b)) { \
dfp.t64[0] = decNumberIsNegative(&dfp.b) ? INT64_MIN : INT64_MAX; \
} else { /* NaN */ \
dfp.t64[0] = INT64_MIN; \
if (decNumberIsSNaN(&dfp.b)) { \
invalid_flags |= FP_VXSNAN; \
} \
} \
dfp_set_FPSCR_flag(&dfp, invalid_flags, FP_VE); \
} else if (unlikely(decNumberIsZero(&dfp.b))) { \
dfp.t64[0] = 0; \
} else { \
decNumberToIntegralExact(&dfp.b, &dfp.b, &dfp.context); \
dfp.t64[0] = decNumberIntegralToInt64(&dfp.b, &dfp.context); \
if (decContextTestStatus(&dfp.context, DEC_Invalid_operation)) { \
dfp.t64[0] = decNumberIsNegative(&dfp.b) ? INT64_MIN : INT64_MAX; \
dfp_set_FPSCR_flag(&dfp, FP_VX | FP_VXCVI, FP_VE); \
} else { \
dfp_check_for_XX(&dfp); \
} \
} \
\
*t = dfp.t64[0]; \
}
DFP_HELPER_CTFIX(dctfix, 64)
DFP_HELPER_CTFIX(dctfixq, 128)
static inline void dfp_set_bcd_digit_64(uint64_t *t, uint8_t digit,
unsigned n)
{
*t |= ((uint64_t)(digit & 0xF) << (n << 2));
}
static inline void dfp_set_bcd_digit_128(uint64_t *t, uint8_t digit,
unsigned n)
{
t[(n & 0x10) ? HI_IDX : LO_IDX] |=
((uint64_t)(digit & 0xF) << ((n & 15) << 2));
}
static inline void dfp_set_sign_64(uint64_t *t, uint8_t sgn)
{
*t <<= 4;
*t |= (sgn & 0xF);
}
static inline void dfp_set_sign_128(uint64_t *t, uint8_t sgn)
{
t[HI_IDX] <<= 4;
t[HI_IDX] |= (t[LO_IDX] >> 60);
t[LO_IDX] <<= 4;
t[LO_IDX] |= (sgn & 0xF);
}
#define DFP_HELPER_DEDPD(op, size) \
void helper_##op(CPUPPCState *env, uint64_t *t, uint64_t *b, uint32_t sp) \
{ \
struct PPC_DFP dfp; \
uint8_t digits[34]; \
int i, N; \
\
dfp_prepare_decimal##size(&dfp, 0, b, env); \
\
decNumberGetBCD(&dfp.b, digits); \
dfp.t64[0] = dfp.t64[1] = 0; \
N = dfp.b.digits; \
\
for (i = 0; (i < N) && (i < (size)/4); i++) { \
dfp_set_bcd_digit_##size(dfp.t64, digits[N-i-1], i); \
} \
\
if (sp & 2) { \
uint8_t sgn; \
\
if (decNumberIsNegative(&dfp.b)) { \
sgn = 0xD; \
} else { \
sgn = ((sp & 1) ? 0xF : 0xC); \
} \
dfp_set_sign_##size(dfp.t64, sgn); \
} \
\
if (size == 64) { \
t[0] = dfp.t64[0]; \
} else if (size == 128) { \
t[0] = dfp.t64[HI_IDX]; \
t[1] = dfp.t64[LO_IDX]; \
} \
}
DFP_HELPER_DEDPD(ddedpd, 64)
DFP_HELPER_DEDPD(ddedpdq, 128)
static inline uint8_t dfp_get_bcd_digit_64(uint64_t *t, unsigned n)
{
return *t >> ((n << 2) & 63) & 15;
}
static inline uint8_t dfp_get_bcd_digit_128(uint64_t *t, unsigned n)
{
return t[(n & 0x10) ? HI_IDX : LO_IDX] >> ((n << 2) & 63) & 15;
}
#define DFP_HELPER_ENBCD(op, size) \
void helper_##op(CPUPPCState *env, uint64_t *t, uint64_t *b, uint32_t s) \
{ \
struct PPC_DFP dfp; \
uint8_t digits[32]; \
int n = 0, offset = 0, sgn = 0, nonzero = 0; \
\
dfp_prepare_decimal##size(&dfp, 0, b, env); \
\
decNumberZero(&dfp.t); \
\
if (s) { \
uint8_t sgnNibble = dfp_get_bcd_digit_##size(dfp.b64, offset++); \
switch (sgnNibble) { \
case 0xD: \
case 0xB: \
sgn = 1; \
break; \
case 0xC: \
case 0xF: \
case 0xA: \
case 0xE: \
sgn = 0; \
break; \
default: \
dfp_set_FPSCR_flag(&dfp, FP_VX | FP_VXCVI, FPSCR_VE); \
return; \
} \
} \
\
while (offset < (size)/4) { \
n++; \
digits[(size)/4-n] = dfp_get_bcd_digit_##size(dfp.b64, offset++); \
if (digits[(size)/4-n] > 10) { \
dfp_set_FPSCR_flag(&dfp, FP_VX | FP_VXCVI, FPSCR_VE); \
return; \
} else { \
nonzero |= (digits[(size)/4-n] > 0); \
} \
} \
\
if (nonzero) { \
decNumberSetBCD(&dfp.t, digits+((size)/4)-n, n); \
} \
\
if (s && sgn) { \
dfp.t.bits |= DECNEG; \
} \
decimal##size##FromNumber((decimal##size *)dfp.t64, &dfp.t, \
&dfp.context); \
dfp_set_FPRF_from_FRT(&dfp); \
if ((size) == 64) { \
t[0] = dfp.t64[0]; \
} else if ((size) == 128) { \
t[0] = dfp.t64[HI_IDX]; \
t[1] = dfp.t64[LO_IDX]; \
} \
}
DFP_HELPER_ENBCD(denbcd, 64)
DFP_HELPER_ENBCD(denbcdq, 128)
#define DFP_HELPER_XEX(op, size) \
void helper_##op(CPUPPCState *env, uint64_t *t, uint64_t *b) \
{ \
struct PPC_DFP dfp; \
\
dfp_prepare_decimal##size(&dfp, 0, b, env); \
\
if (unlikely(decNumberIsSpecial(&dfp.b))) { \
if (decNumberIsInfinite(&dfp.b)) { \
*t = -1; \
} else if (decNumberIsSNaN(&dfp.b)) { \
*t = -3; \
} else if (decNumberIsQNaN(&dfp.b)) { \
*t = -2; \
} else { \
assert(0); \
} \
} else { \
if ((size) == 64) { \
*t = dfp.b.exponent + 398; \
} else if ((size) == 128) { \
*t = dfp.b.exponent + 6176; \
} else { \
assert(0); \
} \
} \
}
DFP_HELPER_XEX(dxex, 64)
DFP_HELPER_XEX(dxexq, 128)
static void dfp_set_raw_exp_64(uint64_t *t, uint64_t raw)
{
*t &= 0x8003ffffffffffffULL;
*t |= (raw << (63-13));
}
static void dfp_set_raw_exp_128(uint64_t *t, uint64_t raw)
{
t[HI_IDX] &= 0x80003fffffffffffULL;
t[HI_IDX] |= (raw << (63-17));
}
#define DFP_HELPER_IEX(op, size) \
void helper_##op(CPUPPCState *env, uint64_t *t, uint64_t *a, uint64_t *b) \
{ \
struct PPC_DFP dfp; \
uint64_t raw_qnan, raw_snan, raw_inf, max_exp; \
int bias; \
int64_t exp = *((int64_t *)a); \
\
dfp_prepare_decimal##size(&dfp, 0, b, env); \
\
if ((size) == 64) { \
max_exp = 767; \
raw_qnan = 0x1F00; \
raw_snan = 0x1F80; \
raw_inf = 0x1E00; \
bias = 398; \
} else if ((size) == 128) { \
max_exp = 12287; \
raw_qnan = 0x1f000; \
raw_snan = 0x1f800; \
raw_inf = 0x1e000; \
bias = 6176; \
} else { \
assert(0); \
} \
\
if (unlikely((exp < 0) || (exp > max_exp))) { \
dfp.t64[0] = dfp.b64[0]; \
dfp.t64[1] = dfp.b64[1]; \
if (exp == -1) { \
dfp_set_raw_exp_##size(dfp.t64, raw_inf); \
} else if (exp == -3) { \
dfp_set_raw_exp_##size(dfp.t64, raw_snan); \
} else { \
dfp_set_raw_exp_##size(dfp.t64, raw_qnan); \
} \
} else { \
dfp.t = dfp.b; \
if (unlikely(decNumberIsSpecial(&dfp.t))) { \
dfp.t.bits &= ~DECSPECIAL; \
} \
dfp.t.exponent = exp - bias; \
decimal##size##FromNumber((decimal##size *)dfp.t64, &dfp.t, \
&dfp.context); \
} \
if (size == 64) { \
t[0] = dfp.t64[0]; \
} else if (size == 128) { \
t[0] = dfp.t64[HI_IDX]; \
t[1] = dfp.t64[LO_IDX]; \
} \
}
DFP_HELPER_IEX(diex, 64)
DFP_HELPER_IEX(diexq, 128)
static void dfp_clear_lmd_from_g5msb(uint64_t *t)
{
/* The most significant 5 bits of the PowerPC DFP format combine bits */
/* from the left-most decimal digit (LMD) and the biased exponent. */
/* This routine clears the LMD bits while preserving the exponent */
/* bits. See "Figure 80: Encoding of bits 0:4 of the G field for */
/* Finite Numbers" in the Power ISA for additional details. */
uint64_t g5msb = (*t >> 58) & 0x1F;
if ((g5msb >> 3) < 3) { /* LMD in [0-7] ? */
*t &= ~(7ULL << 58);
} else {
switch (g5msb & 7) {
case 0:
case 1:
g5msb = 0;
break;
case 2:
case 3:
g5msb = 0x8;
break;
case 4:
case 5:
g5msb = 0x10;
break;
case 6:
g5msb = 0x1E;
break;
case 7:
g5msb = 0x1F;
break;
}
*t &= ~(0x1fULL << 58);
*t |= (g5msb << 58);
}
}
#define DFP_HELPER_SHIFT(op, size, shift_left) \
void helper_##op(CPUPPCState *env, uint64_t *t, uint64_t *a, \
uint32_t sh) \
{ \
struct PPC_DFP dfp; \
unsigned max_digits = ((size) == 64) ? 16 : 34; \
\
dfp_prepare_decimal##size(&dfp, a, 0, env); \
\
if (sh <= max_digits) { \
\
decNumber shd; \
unsigned special = dfp.a.bits & DECSPECIAL; \
\
if (shift_left) { \
decNumberFromUInt32(&shd, sh); \
} else { \
decNumberFromInt32(&shd, -((int32_t)sh)); \
} \
\
dfp.a.bits &= ~DECSPECIAL; \
decNumberShift(&dfp.t, &dfp.a, &shd, &dfp.context); \
\
dfp.t.bits |= special; \
if (special && (dfp.t.digits >= max_digits)) { \
dfp.t.digits = max_digits - 1; \
} \
\
decimal##size##FromNumber((decimal##size *)dfp.t64, &dfp.t, \
&dfp.context); \
} else { \
if ((size) == 64) { \
dfp.t64[0] = dfp.a64[0] & 0xFFFC000000000000ULL; \
dfp_clear_lmd_from_g5msb(dfp.t64); \
} else { \
dfp.t64[HI_IDX] = dfp.a64[HI_IDX] & \
0xFFFFC00000000000ULL; \
dfp_clear_lmd_from_g5msb(dfp.t64 + HI_IDX); \
dfp.t64[LO_IDX] = 0; \
} \
} \
\
if ((size) == 64) { \
t[0] = dfp.t64[0]; \
} else { \
t[0] = dfp.t64[HI_IDX]; \
t[1] = dfp.t64[LO_IDX]; \
} \
}
DFP_HELPER_SHIFT(dscli, 64, 1)
DFP_HELPER_SHIFT(dscliq, 128, 1)
DFP_HELPER_SHIFT(dscri, 64, 0)
DFP_HELPER_SHIFT(dscriq, 128, 0)