diff options
Diffstat (limited to 'qemu/target-ppc/dfp_helper.c')
-rw-r--r-- | qemu/target-ppc/dfp_helper.c | 1316 |
1 files changed, 1316 insertions, 0 deletions
diff --git a/qemu/target-ppc/dfp_helper.c b/qemu/target-ppc/dfp_helper.c new file mode 100644 index 000000000..49820bf21 --- /dev/null +++ b/qemu/target-ppc/dfp_helper.c @@ -0,0 +1,1316 @@ +/* + * 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; + } + g_assert_not_reached(); +} + +#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) |