/* * 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 "qemu/osdep.h" #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); } } 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)