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/* This is a software fixed-point library. Copyright (C) 2007, 2009, 2011 Free Software Foundation, Inc. This file is part of GCC. GCC is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3, or (at your option) any later version. GCC is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. Under Section 7 of GPL version 3, you are granted additional permissions described in the GCC Runtime Library Exception, version 3.1, as published by the Free Software Foundation. You should have received a copy of the GNU General Public License and a copy of the GCC Runtime Library Exception along with this program; see the files COPYING3 and COPYING.RUNTIME respectively. If not, see <http://www.gnu.org/licenses/>. */ /* This implements fixed-point arithmetic. Contributed by Chao-ying Fu <fu@mips.com>. */ /* To use this file, we need to define one of the following: QQ_MODE, UQQ_MODE, HQ_MODE, UHQ_MODE, SQ_MODE, USQ_MODE, DQ_MODE, UDQ_MODE, TQ_MODE, UTQ_MODE, HA_MODE, UHA_MODE, SA_MODE, USA_MODE, DA_MODE, UDA_MODE, TA_MODE, UTA_MODE. Then, all operators for this machine mode will be created. Or, we need to define FROM_* TO_* for conversions from one mode to another mode. The mode could be one of the following: Fract: QQ, UQQ, HQ, UHQ, SQ, USQ, DQ, UDQ, TQ, UTQ Accum: HA, UHA, SA, USA, DA, UDA, TA, UTA Signed integer: QI, HI, SI, DI, TI Unsigned integer: UQI, UHI, USI, UDI, UTI Floating-point: SF, DF Ex: If we define FROM_QQ and TO_SI, the conversion from QQ to SI is generated. */ #include "tconfig.h" #include "tsystem.h" #include "coretypes.h" #include "tm.h" #include "libgcc_tm.h" #ifndef MIN_UNITS_PER_WORD #define MIN_UNITS_PER_WORD UNITS_PER_WORD #endif #include "fixed-bit.h" #if defined(FIXED_ADD) && defined(L_add) FIXED_C_TYPE FIXED_ADD (FIXED_C_TYPE a, FIXED_C_TYPE b) { FIXED_C_TYPE c; INT_C_TYPE x, y, z; memcpy (&x, &a, FIXED_SIZE); memcpy (&y, &b, FIXED_SIZE); z = x + y; #if HAVE_PADDING_BITS z = z << PADDING_BITS; z = z >> PADDING_BITS; #endif memcpy (&c, &z, FIXED_SIZE); return c; } #endif /* FIXED_ADD */ #if defined(FIXED_SSADD) && defined(L_ssadd) FIXED_C_TYPE FIXED_SSADD (FIXED_C_TYPE a, FIXED_C_TYPE b) { FIXED_C_TYPE c; INT_C_TYPE x, y, z; memcpy (&x, &a, FIXED_SIZE); memcpy (&y, &b, FIXED_SIZE); z = x + y; if ((((x ^ y) >> I_F_BITS) & 1) == 0) { if (((z ^ x) >> I_F_BITS) & 1) { z = 1; z = z << I_F_BITS; if (x >= 0) z--; } } #if HAVE_PADDING_BITS z = z << PADDING_BITS; z = z >> PADDING_BITS; #endif memcpy (&c, &z, FIXED_SIZE); return c; } #endif /* FIXED_SSADD */ #if defined(FIXED_USADD) && defined(L_usadd) FIXED_C_TYPE FIXED_USADD (FIXED_C_TYPE a, FIXED_C_TYPE b) { FIXED_C_TYPE c; INT_C_TYPE x, y, z; memcpy (&x, &a, FIXED_SIZE); memcpy (&y, &b, FIXED_SIZE); z = x + y; #if HAVE_PADDING_BITS z = z << PADDING_BITS; z = z >> PADDING_BITS; #endif if (z < x || z < y) /* max */ { z = -1; #if HAVE_PADDING_BITS z = z << PADDING_BITS; z = z >> PADDING_BITS; #endif } memcpy (&c, &z, FIXED_SIZE); return c; } #endif /* FIXED_USADD */ #if defined(FIXED_SUB) && defined(L_sub) FIXED_C_TYPE FIXED_SUB (FIXED_C_TYPE a, FIXED_C_TYPE b) { FIXED_C_TYPE c; INT_C_TYPE x, y, z; memcpy (&x, &a, FIXED_SIZE); memcpy (&y, &b, FIXED_SIZE); z = x - y; #if HAVE_PADDING_BITS z = z << PADDING_BITS; z = z >> PADDING_BITS; #endif memcpy (&c, &z, FIXED_SIZE); return c; } #endif /* FIXED_SUB */ #if defined(FIXED_SSSUB) && defined(L_sssub) FIXED_C_TYPE FIXED_SSSUB (FIXED_C_TYPE a, FIXED_C_TYPE b) { FIXED_C_TYPE c; INT_C_TYPE x, y, z; memcpy (&x, &a, FIXED_SIZE); memcpy (&y, &b, FIXED_SIZE); z = x - y; if (((x ^ y) >> I_F_BITS) & 1) { if (((z ^ x) >> I_F_BITS) & 1) { z = 1; z = z << I_F_BITS; if (x >= 0) z--; } } #if HAVE_PADDING_BITS z = z << PADDING_BITS; z = z >> PADDING_BITS; #endif memcpy (&c, &z, FIXED_SIZE); return c; } #endif /* FIXED_SSSUB */ #if defined(FIXED_USSUB) && defined(L_ussub) FIXED_C_TYPE FIXED_USSUB (FIXED_C_TYPE a, FIXED_C_TYPE b) { FIXED_C_TYPE c; INT_C_TYPE x, y, z; memcpy (&x, &a, FIXED_SIZE); memcpy (&y, &b, FIXED_SIZE); z = x - y; if (x < y) z = 0; #if HAVE_PADDING_BITS z = z << PADDING_BITS; z = z >> PADDING_BITS; #endif memcpy (&c, &z, FIXED_SIZE); return c; } #endif /* FIXED_USSUB */ #if defined(FIXED_SATURATE1) && defined(L_saturate1) void FIXED_SATURATE1 (DINT_C_TYPE *a) { DINT_C_TYPE max, min; max = (DINT_C_TYPE)1 << I_F_BITS; max = max - 1; #if MODE_UNSIGNED == 0 min = (DINT_C_TYPE)1 << (2 * FIXED_WIDTH - 1); min = min >> (2 * FIXED_WIDTH - 1 - I_F_BITS); #else min = 0; #endif if (*a > max) *a = max; else if (*a < min) *a = min; } #endif /* FIXED_SATURATE1 */ #if defined(FIXED_SATURATE2) && defined(L_saturate2) void FIXED_SATURATE2 (INT_C_TYPE *high, INT_C_TYPE *low) { INT_C_TYPE r_max, s_max, r_min, s_min; r_max = 0; #if (MODE_UNSIGNED == 0) || HAVE_PADDING_BITS s_max = (INT_C_TYPE)1 << I_F_BITS; s_max = s_max - 1; #else s_max = -1; #endif #if MODE_UNSIGNED == 0 r_min = -1; s_min = (INT_C_TYPE)1 << (FIXED_WIDTH - 1); s_min = s_min >> (FIXED_WIDTH - 1 - I_F_BITS); #else r_min = 0; s_min = 0; #endif if (*high > r_max || (*high == r_max && (UINT_C_TYPE)(*low) > (UINT_C_TYPE)s_max)) { *high = r_max; *low = s_max; } else if (*high < r_min || (*high == r_min && (UINT_C_TYPE)(*low) < (UINT_C_TYPE)s_min)) { *high = r_min; *low = s_min; } } #endif /* FIXED_SATURATE2 */ #if defined(FIXED_MULHELPER) && defined(L_mulhelper) FIXED_C_TYPE FIXED_MULHELPER (FIXED_C_TYPE a, FIXED_C_TYPE b, word_type satp) { FIXED_C_TYPE c; INT_C_TYPE x, y; #if defined (DINT_C_TYPE) INT_C_TYPE z; DINT_C_TYPE dx, dy, dz; memcpy (&x, &a, FIXED_SIZE); memcpy (&y, &b, FIXED_SIZE); dx = (DINT_C_TYPE) x; dy = (DINT_C_TYPE) y; dz = dx * dy; /* Round the result by adding (1 << (FBITS -1)). */ dz += ((DINT_C_TYPE) 1 << (FBITS - 1)); dz = dz >> FBITS; if (satp) FIXED_SATURATE1 (&dz); z = (INT_C_TYPE) dz; #if HAVE_PADDING_BITS z = z << PADDING_BITS; z = z >> PADDING_BITS; #endif memcpy (&c, &z, FIXED_SIZE); return c; #else /* No DINT_C_TYPE */ /* The result of multiplication expands to two INT_C_TYPE. */ INTunion aa, bb; INTunion a_high, a_low, b_high, b_low; INTunion high_high, high_low, low_high, low_low; INTunion r, s, temp1, temp2; INT_C_TYPE carry = 0; INT_C_TYPE z; memcpy (&x, &a, FIXED_SIZE); memcpy (&y, &b, FIXED_SIZE); /* Decompose a and b. */ aa.ll = x; bb.ll = y; a_high.s.low = aa.s.high; a_high.s.high = 0; a_low.s.low = aa.s.low; a_low.s.high = 0; b_high.s.low = bb.s.high; b_high.s.high = 0; b_low.s.low = bb.s.low; b_low.s.high = 0; /* Perform four multiplications. */ low_low.ll = a_low.ll * b_low.ll; low_high.ll = a_low.ll * b_high.ll; high_low.ll = a_high.ll * b_low.ll; high_high.ll = a_high.ll * b_high.ll; /* Accumulate four results to {r, s}. */ temp1.s.high = high_low.s.low; temp1.s.low = 0; s.ll = low_low.ll + temp1.ll; if ((UINT_C_TYPE) s.ll < (UINT_C_TYPE) low_low.ll || (UINT_C_TYPE) s.ll < (UINT_C_TYPE) temp1.ll) carry ++; /* Carry. */ temp1.ll = s.ll; temp2.s.high = low_high.s.low; temp2.s.low = 0; s.ll = temp1.ll + temp2.ll; if ((UINT_C_TYPE) s.ll < (UINT_C_TYPE) temp1.ll || (UINT_C_TYPE) s.ll < (UINT_C_TYPE) temp2.ll) carry ++; /* Carry. */ temp1.s.low = high_low.s.high; temp1.s.high = 0; r.ll = high_high.ll + temp1.ll; temp1.s.low = low_high.s.high; temp1.s.high = 0; r.ll = r.ll + temp1.ll + carry; #if MODE_UNSIGNED == 0 /* For signed types, we need to add neg(y) to r, if x < 0. */ if (x < 0) r.ll = r.ll - y; /* We need to add neg(x) to r, if y < 0. */ if (y < 0) r.ll = r.ll - x; #endif /* Round the result by adding (1 << (FBITS -1)). */ temp1.ll = s.ll; s.ll += ((INT_C_TYPE) 1 << (FBITS -1)); if ((UINT_C_TYPE) s.ll < (UINT_C_TYPE) temp1.ll || (UINT_C_TYPE) s.ll < (UINT_C_TYPE) ((INT_C_TYPE) 1 << (FBITS -1))) r.ll += 1; /* Shift right the result by FBITS. */ #if FBITS == FIXED_WIDTH /* This happens only for unsigned types without any padding bits. So, it is safe to set r.ll to 0 as it is logically shifted right. */ s.ll = r.ll; r.ll = 0; #else s.ll = ((UINT_C_TYPE)s.ll) >> FBITS; temp1.ll = r.ll << (FIXED_WIDTH - FBITS); s.ll = s.ll | temp1.ll; r.ll = r.ll >> FBITS; #endif if (satp) FIXED_SATURATE2 (&r.ll, &s.ll); z = (INT_C_TYPE) s.ll; #if HAVE_PADDING_BITS z = z << PADDING_BITS; z = z >> PADDING_BITS; #endif memcpy (&c, &z, FIXED_SIZE); return c; #endif } #endif /* FIXED_MULHELPER */ #if defined(FIXED_MUL) && defined(L_mul) FIXED_C_TYPE FIXED_MUL (FIXED_C_TYPE a, FIXED_C_TYPE b) { return FIXED_MULHELPER (a, b, 0); } #endif /* FIXED_MUL */ #if defined(FIXED_SSMUL) && defined(L_ssmul) FIXED_C_TYPE FIXED_SSMUL (FIXED_C_TYPE a, FIXED_C_TYPE b) { return FIXED_MULHELPER (a, b, 1); } #endif /* FIXED_SSMUL */ #if defined(FIXED_USMUL) && defined(L_usmul) FIXED_C_TYPE FIXED_USMUL (FIXED_C_TYPE a, FIXED_C_TYPE b) { return FIXED_MULHELPER (a, b, 1); } #endif /* FIXED_USMUL */ #if defined(FIXED_DIVHELPER) && defined(L_divhelper) FIXED_C_TYPE FIXED_DIVHELPER (FIXED_C_TYPE a, FIXED_C_TYPE b, word_type satp) { FIXED_C_TYPE c; INT_C_TYPE x, y; INT_C_TYPE z; #if defined (DINT_C_TYPE) DINT_C_TYPE dx, dy, dz; memcpy (&x, &a, FIXED_SIZE); memcpy (&y, &b, FIXED_SIZE); dx = (DINT_C_TYPE) x; dy = (DINT_C_TYPE) y; dx = dx << FBITS; dz = dx / dy; if (satp) FIXED_SATURATE1 (&dz); z = (INT_C_TYPE) dz; #if HAVE_PADDING_BITS z = z << PADDING_BITS; z = z >> PADDING_BITS; #endif memcpy (&c, &z, FIXED_SIZE); return c; #else /* No DINT_C_TYPE */ INT_C_TYPE pos_a, pos_b, r, s; INT_C_TYPE quo_r, quo_s, mod, temp; word_type i; #if MODE_UNSIGNED == 0 word_type num_of_neg = 0; #endif memcpy (&x, &a, FIXED_SIZE); memcpy (&y, &b, FIXED_SIZE); pos_a = x; pos_b = y; #if MODE_UNSIGNED == 0 /* If a < 0, negate a. */ if (pos_a < 0) { pos_a = -pos_a; num_of_neg ++; } /* If b < 0, negate b. */ if (pos_b < 0) { pos_b = -pos_b; num_of_neg ++; } #endif /* Left shift pos_a to {r, s} by FBITS. */ #if FBITS == FIXED_WIDTH /* This happens only for unsigned types without any padding bits. */ r = pos_a; s = 0; #else s = pos_a << FBITS; r = pos_a >> (FIXED_WIDTH - FBITS); #endif /* Unsigned divide r by pos_b to quo_r. The remainder is in mod. */ quo_r = (UINT_C_TYPE)r / (UINT_C_TYPE)pos_b; mod = (UINT_C_TYPE)r % (UINT_C_TYPE)pos_b; quo_s = 0; for (i = 0; i < FIXED_WIDTH; i++) { /* Record the leftmost bit of mod. */ word_type leftmost_mode = (mod >> (FIXED_WIDTH - 1)) & 1; /* Shift left mod by 1 bit. */ mod = mod << 1; /* Test the leftmost bit of s to add to mod. */ if ((s >> (FIXED_WIDTH - 1)) & 1) mod ++; /* Shift left quo_s by 1 bit. */ quo_s = quo_s << 1; /* Try to calculate (mod - pos_b). */ temp = mod - pos_b; if (leftmost_mode || (UINT_C_TYPE)mod >= (UINT_C_TYPE)pos_b) { quo_s ++; mod = temp; } /* Shift left s by 1 bit. */ s = s << 1; } #if MODE_UNSIGNED == 0 if (num_of_neg == 1) { quo_s = -quo_s; if (quo_s == 0) quo_r = -quo_r; else quo_r = ~quo_r; } #endif if (satp) FIXED_SATURATE2 (&quo_r, &quo_s); z = quo_s; #if HAVE_PADDING_BITS z = z << PADDING_BITS; z = z >> PADDING_BITS; #endif memcpy (&c, &z, FIXED_SIZE); return c; #endif } #endif /* FIXED_DIVHELPER */ #if defined(FIXED_DIV) && defined(L_div) FIXED_C_TYPE FIXED_DIV (FIXED_C_TYPE a, FIXED_C_TYPE b) { return FIXED_DIVHELPER (a, b, 0); } #endif /* FIXED_DIV */ #if defined(FIXED_UDIV) && defined(L_udiv) FIXED_C_TYPE FIXED_UDIV (FIXED_C_TYPE a, FIXED_C_TYPE b) { return FIXED_DIVHELPER (a, b, 0); } #endif /* FIXED_UDIV */ #if defined(FIXED_SSDIV) && defined(L_ssdiv) FIXED_C_TYPE FIXED_SSDIV (FIXED_C_TYPE a, FIXED_C_TYPE b) { return FIXED_DIVHELPER (a, b, 1); } #endif /* FIXED_SSDIV */ #if defined(FIXED_USDIV) && defined(L_usdiv) FIXED_C_TYPE FIXED_USDIV (FIXED_C_TYPE a, FIXED_C_TYPE b) { return FIXED_DIVHELPER (a, b, 1); } #endif /* FIXED_USDIV */ #if defined(FIXED_NEG) && defined(L_neg) FIXED_C_TYPE FIXED_NEG (FIXED_C_TYPE a) { FIXED_C_TYPE c; INT_C_TYPE x, z; memcpy (&x, &a, FIXED_SIZE); z = -x; #if HAVE_PADDING_BITS z = z << PADDING_BITS; z = z >> PADDING_BITS; #endif memcpy (&c, &z, FIXED_SIZE); return c; } #endif /* FIXED_NEG */ #if defined(FIXED_SSNEG) && defined(L_ssneg) FIXED_C_TYPE FIXED_SSNEG (FIXED_C_TYPE a) { FIXED_C_TYPE c; INT_C_TYPE x, y, z; memcpy (&y, &a, FIXED_SIZE); x = 0; z = x - y; if (((x ^ y) >> I_F_BITS) & 1) { if (((z ^ x) >> I_F_BITS) & 1) { z = 1; z = z << I_F_BITS; if (x >= 0) z--; } } #if HAVE_PADDING_BITS z = z << PADDING_BITS; z = z >> PADDING_BITS; #endif memcpy (&c, &z, FIXED_SIZE); return c; } #endif /* FIXED_SSNEG */ #if defined(FIXED_USNEG) && defined(L_usneg) FIXED_C_TYPE FIXED_USNEG (FIXED_C_TYPE a __attribute__ ((__unused__))) { FIXED_C_TYPE c; INT_C_TYPE z; z = 0; memcpy (&c, &z, FIXED_SIZE); return c; } #endif /* FIXED_USNEG */ #if defined(FIXED_ASHLHELPER) && defined(L_ashlhelper) FIXED_C_TYPE FIXED_ASHLHELPER (FIXED_C_TYPE a, word_type b, word_type satp) { FIXED_C_TYPE c; INT_C_TYPE x, z; #if defined (DINT_C_TYPE) DINT_C_TYPE dx, dz; memcpy (&x, &a, FIXED_SIZE); dx = (DINT_C_TYPE) x; if (b >= FIXED_WIDTH) dz = dx << FIXED_WIDTH; else dz = dx << b; if (satp) FIXED_SATURATE1 (&dz); z = (INT_C_TYPE) dz; #if HAVE_PADDING_BITS z = z << PADDING_BITS; z = z >> PADDING_BITS; #endif memcpy (&c, &z, FIXED_SIZE); return c; #else /* No DINT_C_TYPE */ INT_C_TYPE r, s; memcpy (&x, &a, FIXED_SIZE); /* We need to shift left x by b bits to {r, s}. */ if (b >= FIXED_WIDTH) { r = b; s = 0; } else { s = x << b; r = x >> (FIXED_WIDTH - b); } if (satp) FIXED_SATURATE2 (&r, &s); z = s; #if HAVE_PADDING_BITS z = z << PADDING_BITS; z = z >> PADDING_BITS; #endif memcpy (&c, &z, FIXED_SIZE); return c; #endif } #endif /* FIXED_ASHLHELPER */ #if defined(FIXED_ASHL) && defined(L_ashl) FIXED_C_TYPE FIXED_ASHL (FIXED_C_TYPE a, word_type b) { return FIXED_ASHLHELPER (a, b, 0); } #endif /* FIXED_ASHL */ #if defined(FIXED_ASHR) && defined(L_ashr) FIXED_C_TYPE FIXED_ASHR (FIXED_C_TYPE a, word_type b) { FIXED_C_TYPE c; INT_C_TYPE x, z; memcpy (&x, &a, FIXED_SIZE); z = x >> b; #if HAVE_PADDING_BITS z = z << PADDING_BITS; z = z >> PADDING_BITS; #endif memcpy (&c, &z, FIXED_SIZE); return c; } #endif /* FIXED_ASHR */ #if defined(FIXED_LSHR) && defined(L_lshr) FIXED_C_TYPE FIXED_LSHR (FIXED_C_TYPE a, word_type b) { FIXED_C_TYPE c; INT_C_TYPE x, z; memcpy (&x, &a, FIXED_SIZE); z = x >> b; #if HAVE_PADDING_BITS z = z << PADDING_BITS; z = z >> PADDING_BITS; #endif memcpy (&c, &z, FIXED_SIZE); return c; } #endif /* FIXED_LSHR */ #if defined(FIXED_SSASHL) && defined(L_ssashl) FIXED_C_TYPE FIXED_SSASHL (FIXED_C_TYPE a, word_type b) { return FIXED_ASHLHELPER (a, b, 1); } #endif /* FIXED_SSASHL */ #if defined(FIXED_USASHL) && defined(L_usashl) FIXED_C_TYPE FIXED_USASHL (FIXED_C_TYPE a, word_type b) { return FIXED_ASHLHELPER (a, b, 1); } #endif /* FIXED_USASHL */ #if defined(FIXED_CMP) && defined(L_cmp) word_type FIXED_CMP (FIXED_C_TYPE a, FIXED_C_TYPE b) { INT_C_TYPE x, y; memcpy (&x, &a, FIXED_SIZE); memcpy (&y, &b, FIXED_SIZE); if (x < y) return 0; else if (x > y) return 2; return 1; } #endif /* FIXED_CMP */ /* Fixed -> Fixed. */ #if defined(FRACT) && defined(L_fract) && FROM_TYPE == 4 && TO_TYPE == 4 TO_FIXED_C_TYPE FRACT (FROM_FIXED_C_TYPE a) { TO_FIXED_C_TYPE c; FROM_INT_C_TYPE x; TO_INT_C_TYPE z; int shift_amount; memcpy (&x, &a, FROM_FIXED_SIZE); #if TO_FBITS > FROM_FBITS /* Need left shift. */ shift_amount = TO_FBITS - FROM_FBITS; z = (TO_INT_C_TYPE) x; z = z << shift_amount; #else /* TO_FBITS <= FROM_FBITS. Need right Shift. */ shift_amount = FROM_FBITS - TO_FBITS; x = x >> shift_amount; z = (TO_INT_C_TYPE) x; #endif /* TO_FBITS > FROM_FBITS */ #if TO_HAVE_PADDING_BITS z = z << TO_PADDING_BITS; z = z >> TO_PADDING_BITS; #endif memcpy (&c, &z, TO_FIXED_SIZE); return c; } #endif /* FRACT && FROM_TYPE == 4 && TO_TYPE == 4 */ /* Fixed -> Fixed with saturation. */ #if defined(SATFRACT) && defined(L_satfract) && FROM_TYPE == 4 && TO_TYPE == 4 TO_FIXED_C_TYPE SATFRACT (FROM_FIXED_C_TYPE a) { TO_FIXED_C_TYPE c; TO_INT_C_TYPE z; FROM_INT_C_TYPE x; #if FROM_MODE_UNSIGNED == 0 BIG_SINT_C_TYPE high, low; BIG_SINT_C_TYPE max_high, max_low; BIG_SINT_C_TYPE min_high, min_low; #else BIG_UINT_C_TYPE high, low; BIG_UINT_C_TYPE max_high, max_low; BIG_UINT_C_TYPE min_high, min_low; #endif #if TO_FBITS > FROM_FBITS BIG_UINT_C_TYPE utemp; #endif #if TO_MODE_UNSIGNED == 0 BIG_SINT_C_TYPE stemp; #endif #if TO_FBITS != FROM_FBITS int shift_amount; #endif memcpy (&x, &a, FROM_FIXED_SIZE); /* Step 1. We need to store x to {high, low}. */ #if FROM_MODE_UNSIGNED == 0 low = (BIG_SINT_C_TYPE) x; if (x < 0) high = -1; else high = 0; #else low = (BIG_UINT_C_TYPE) x; high = 0; #endif /* Step 2. We need to shift {high, low}. */ #if TO_FBITS > FROM_FBITS /* Left shift. */ shift_amount = TO_FBITS - FROM_FBITS; utemp = (BIG_UINT_C_TYPE) low; utemp = utemp >> (BIG_WIDTH - shift_amount); high = ((BIG_UINT_C_TYPE)(high << shift_amount)) | utemp; low = low << shift_amount; #elif TO_FBITS < FROM_FBITS /* Right shift. */ shift_amount = FROM_FBITS - TO_FBITS; low = low >> shift_amount; #endif /* Step 3. Compare {high, low} with max and min of TO_FIXED_C_TYPE. */ max_high = 0; #if BIG_WIDTH > TO_FIXED_WIDTH || TO_MODE_UNSIGNED == 0 || TO_HAVE_PADDING_BITS max_low = (BIG_UINT_C_TYPE)1 << TO_I_F_BITS; max_low = max_low - 1; #else max_low = -1; #endif #if TO_MODE_UNSIGNED == 0 min_high = -1; stemp = (BIG_SINT_C_TYPE)1 << (BIG_WIDTH - 1); stemp = stemp >> (BIG_WIDTH - 1 - TO_I_F_BITS); min_low = stemp; #else min_high = 0; min_low = 0; #endif #if FROM_MODE_UNSIGNED == 0 && TO_MODE_UNSIGNED == 0 /* Signed -> Signed. */ if ((BIG_SINT_C_TYPE) high > (BIG_SINT_C_TYPE) max_high || ((BIG_SINT_C_TYPE) high == (BIG_SINT_C_TYPE) max_high && (BIG_UINT_C_TYPE) low > (BIG_UINT_C_TYPE) max_low)) low = max_low; /* Maximum. */ else if ((BIG_SINT_C_TYPE) high < (BIG_SINT_C_TYPE) min_high || ((BIG_SINT_C_TYPE) high == (BIG_SINT_C_TYPE) min_high && (BIG_UINT_C_TYPE) low < (BIG_UINT_C_TYPE) min_low)) low = min_low; /* Minimum. */ #elif FROM_MODE_UNSIGNED == 1 && TO_MODE_UNSIGNED == 1 /* Unigned -> Unsigned. */ if ((BIG_UINT_C_TYPE) high > (BIG_UINT_C_TYPE) max_high || ((BIG_UINT_C_TYPE) high == (BIG_UINT_C_TYPE) max_high && (BIG_UINT_C_TYPE) low > (BIG_UINT_C_TYPE) max_low)) low = max_low; /* Maximum. */ #elif FROM_MODE_UNSIGNED == 0 && TO_MODE_UNSIGNED == 1 /* Signed -> Unsigned. */ if (x < 0) low = 0; /* Minimum. */ else if ((BIG_UINT_C_TYPE) high > (BIG_UINT_C_TYPE) max_high || ((BIG_UINT_C_TYPE) high == (BIG_UINT_C_TYPE) max_high && (BIG_UINT_C_TYPE) low > (BIG_UINT_C_TYPE) max_low)) low = max_low; /* Maximum. */ #elif FROM_MODE_UNSIGNED == 1 && TO_MODE_UNSIGNED == 0 /* Unsigned -> Signed. */ if ((BIG_SINT_C_TYPE) high < 0) low = max_low; /* Maximum. */ else if ((BIG_SINT_C_TYPE) high > (BIG_SINT_C_TYPE) max_high || ((BIG_SINT_C_TYPE) high == (BIG_SINT_C_TYPE) max_high && (BIG_UINT_C_TYPE) low > (BIG_UINT_C_TYPE) max_low)) low = max_low; /* Maximum. */ #endif /* Step 4. Store the result. */ z = (TO_INT_C_TYPE) low; #if TO_HAVE_PADDING_BITS z = z << TO_PADDING_BITS; z = z >> TO_PADDING_BITS; #endif memcpy (&c, &z, TO_FIXED_SIZE); return c; } #endif /* defined(SATFRACT) && FROM_TYPE == 4 && TO_TYPE == 4 */ /* Fixed -> Int. */ #if defined(FRACT) && defined(L_fract) && FROM_TYPE == 4 && TO_TYPE == 1 TO_INT_C_TYPE FRACT (FROM_FIXED_C_TYPE a) { FROM_INT_C_TYPE x; TO_INT_C_TYPE z; FROM_INT_C_TYPE i = 0; memcpy (&x, &a, FROM_FIXED_SIZE); #if FROM_MODE_UNSIGNED == 0 if (x < 0) { #if FROM_FIXED_WIDTH == FROM_FBITS if (x != 0) i = 1; #else if (((FROM_INT_C_TYPE)(x << (FROM_FIXED_WIDTH - FROM_FBITS))) != 0) i = 1; #endif } #endif #if FROM_FIXED_WIDTH == FROM_FBITS x = 0; #else x = x >> FROM_FBITS; #endif x = x + i; z = (TO_INT_C_TYPE) x; return z; } #endif /* defined(FRACT) && FROM_TYPE == 4 && TO_TYPE == 1 */ /* Fixed -> Unsigned int. */ #if defined(FRACTUNS) && defined(L_fractuns) && FROM_TYPE == 4 && TO_TYPE == 2 TO_INT_C_TYPE FRACTUNS (FROM_FIXED_C_TYPE a) { FROM_INT_C_TYPE x; TO_INT_C_TYPE z; FROM_INT_C_TYPE i = 0; memcpy (&x, &a, FROM_FIXED_SIZE); #if FROM_MODE_UNSIGNED == 0 if (x < 0) { #if FROM_FIXED_WIDTH == FROM_FBITS if (x != 0) i = 1; #else if (((FROM_INT_C_TYPE)(x << (FROM_FIXED_WIDTH - FROM_FBITS))) != 0) i = 1; #endif } #endif #if FROM_FIXED_WIDTH == FROM_FBITS x = 0; #else x = x >> FROM_FBITS; #endif x = x + i; z = (TO_INT_C_TYPE) x; return z; } #endif /* defined(FRACTUNS) && FROM_TYPE == 4 && TO_TYPE == 2 */ /* Int -> Fixed. */ #if defined(FRACT) && defined(L_fract) && FROM_TYPE == 1 && TO_TYPE == 4 TO_FIXED_C_TYPE FRACT (FROM_INT_C_TYPE a) { TO_FIXED_C_TYPE c; TO_INT_C_TYPE z; z = (TO_INT_C_TYPE) a; #if TO_FIXED_WIDTH == TO_FBITS z = 0; #else z = z << TO_FBITS; #endif #if TO_HAVE_PADDING_BITS z = z << TO_PADDING_BITS; z = z >> TO_PADDING_BITS; #endif memcpy (&c, &z, TO_FIXED_SIZE); return c; } #endif /* defined(FRACT) && FROM_TYPE == 1 && TO_TYPE == 4 */ /* Signed int -> Fixed with saturation. */ #if defined(SATFRACT) && defined(L_satfract) &&FROM_TYPE == 1 && TO_TYPE == 4 TO_FIXED_C_TYPE SATFRACT (FROM_INT_C_TYPE a) { TO_FIXED_C_TYPE c; TO_INT_C_TYPE z; FROM_INT_C_TYPE x = a; BIG_SINT_C_TYPE high, low; BIG_SINT_C_TYPE max_high, max_low; BIG_SINT_C_TYPE min_high, min_low; #if TO_MODE_UNSIGNED == 0 BIG_SINT_C_TYPE stemp; #endif #if BIG_WIDTH != TO_FBITS BIG_UINT_C_TYPE utemp; int shift_amount; #endif /* Step 1. We need to store x to {high, low}. */ low = (BIG_SINT_C_TYPE) x; if (x < 0) high = -1; else high = 0; /* Step 2. We need to left shift {high, low}. */ #if BIG_WIDTH == TO_FBITS high = low; low = 0; #else shift_amount = TO_FBITS; utemp = (BIG_UINT_C_TYPE) low; utemp = utemp >> (BIG_WIDTH - shift_amount); high = ((BIG_UINT_C_TYPE)(high << shift_amount)) | utemp; low = low << shift_amount; #endif /* Step 3. Compare {high, low} with max and min of TO_FIXED_C_TYPE. */ max_high = 0; #if BIG_WIDTH > TO_FIXED_WIDTH || TO_MODE_UNSIGNED == 0 || TO_HAVE_PADDING_BITS max_low = (BIG_UINT_C_TYPE)1 << TO_I_F_BITS; max_low = max_low - 1; #else max_low = -1; #endif #if TO_MODE_UNSIGNED == 0 min_high = -1; stemp = (BIG_SINT_C_TYPE)1 << (BIG_WIDTH - 1); stemp = stemp >> (BIG_WIDTH - 1 - TO_I_F_BITS); min_low = stemp; #else min_high = 0; min_low = 0; #endif #if TO_MODE_UNSIGNED == 0 /* Signed -> Signed. */ if ((BIG_SINT_C_TYPE) high > (BIG_SINT_C_TYPE) max_high || ((BIG_SINT_C_TYPE) high == (BIG_SINT_C_TYPE) max_high && (BIG_UINT_C_TYPE) low > (BIG_UINT_C_TYPE) max_low)) low = max_low; /* Maximum. */ else if ((BIG_SINT_C_TYPE) high < (BIG_SINT_C_TYPE) min_high || ((BIG_SINT_C_TYPE) high == (BIG_SINT_C_TYPE) min_high && (BIG_UINT_C_TYPE) low < (BIG_UINT_C_TYPE) min_low)) low = min_low; /* Minimum. */ #else /* Signed -> Unsigned. */ if (x < 0) low = 0; /* Minimum. */ else if ((BIG_UINT_C_TYPE) high > (BIG_UINT_C_TYPE) max_high || ((BIG_UINT_C_TYPE) high == (BIG_UINT_C_TYPE) max_high && (BIG_UINT_C_TYPE) low > (BIG_UINT_C_TYPE) max_low)) low = max_low; /* Maximum. */ #endif /* Step 4. Store the result. */ z = (TO_INT_C_TYPE) low; #if TO_HAVE_PADDING_BITS z = z << TO_PADDING_BITS; z = z >> TO_PADDING_BITS; #endif memcpy (&c, &z, TO_FIXED_SIZE); return c; } #endif /* defined(SATFRACT) && FROM_TYPE == 1 && TO_TYPE == 4 */ /* Unsigned int -> Fixed. */ #if defined(FRACTUNS) && defined(L_fractuns) &&FROM_TYPE == 2 && TO_TYPE == 4 TO_FIXED_C_TYPE FRACTUNS (FROM_INT_C_TYPE a) { TO_FIXED_C_TYPE c; TO_INT_C_TYPE z; z = (TO_INT_C_TYPE) a; #if TO_FIXED_WIDTH == TO_FBITS z = 0; #else z = z << TO_FBITS; #endif #if TO_HAVE_PADDING_BITS z = z << TO_PADDING_BITS; z = z >> TO_PADDING_BITS; #endif memcpy (&c, &z, TO_FIXED_SIZE); return c; } #endif /* defined(FRACTUNS) && FROM_TYPE == 2 && TO_TYPE == 4 */ /* Unsigned int -> Fixed with saturation. */ #if defined(SATFRACTUNS) && defined(L_satfractuns) && FROM_TYPE == 2 && TO_TYPE == 4 TO_FIXED_C_TYPE SATFRACTUNS (FROM_INT_C_TYPE a) { TO_FIXED_C_TYPE c; TO_INT_C_TYPE z; FROM_INT_C_TYPE x = a; BIG_UINT_C_TYPE high, low; BIG_UINT_C_TYPE max_high, max_low; #if BIG_WIDTH != TO_FBITS BIG_UINT_C_TYPE utemp; int shift_amount; #endif /* Step 1. We need to store x to {high, low}. */ low = (BIG_UINT_C_TYPE) x; high = 0; /* Step 2. We need to left shift {high, low}. */ #if BIG_WIDTH == TO_FBITS high = low; low = 0; #else shift_amount = TO_FBITS; utemp = (BIG_UINT_C_TYPE) low; utemp = utemp >> (BIG_WIDTH - shift_amount); high = ((BIG_UINT_C_TYPE)(high << shift_amount)) | utemp; low = low << shift_amount; #endif /* Step 3. Compare {high, low} with max and min of TO_FIXED_C_TYPE. */ max_high = 0; #if BIG_WIDTH > TO_FIXED_WIDTH || TO_MODE_UNSIGNED == 0 || TO_HAVE_PADDING_BITS max_low = (BIG_UINT_C_TYPE)1 << TO_I_F_BITS; max_low = max_low - 1; #else max_low = -1; #endif #if TO_MODE_UNSIGNED == 1 /* Unigned -> Unsigned. */ if ((BIG_UINT_C_TYPE) high > (BIG_UINT_C_TYPE) max_high || ((BIG_UINT_C_TYPE) high == (BIG_UINT_C_TYPE) max_high && (BIG_UINT_C_TYPE) low > (BIG_UINT_C_TYPE) max_low)) low = max_low; /* Maximum. */ #else /* Unsigned -> Signed. */ if ((BIG_SINT_C_TYPE) high < 0) low = max_low; /* Maximum. */ else if ((BIG_SINT_C_TYPE) high > (BIG_SINT_C_TYPE) max_high || ((BIG_SINT_C_TYPE) high == (BIG_SINT_C_TYPE) max_high && (BIG_UINT_C_TYPE) low > (BIG_UINT_C_TYPE) max_low)) low = max_low; /* Maximum. */ #endif /* Step 4. Store the result. */ z = (TO_INT_C_TYPE) low; #if TO_HAVE_PADDING_BITS z = z << TO_PADDING_BITS; z = z >> TO_PADDING_BITS; #endif memcpy (&c, &z, TO_FIXED_SIZE); return c; } #endif /* defined(SATFRACTUNS) && FROM_TYPE == 2 && TO_TYPE == 4 */ /* Fixed -> Float. */ #if defined(FRACT) && defined(L_fract) && FROM_TYPE == 4 && TO_TYPE == 3 TO_FLOAT_C_TYPE FRACT (FROM_FIXED_C_TYPE a) { FROM_INT_C_TYPE x; TO_FLOAT_C_TYPE z; memcpy (&x, &a, FROM_FIXED_SIZE); z = (TO_FLOAT_C_TYPE) x; z = z / BASE; return z; } #endif /* defined(FRACT) && FROM_TYPE == 4 && TO_TYPE == 3 */ /* Float -> Fixed. */ #if defined(FRACT) && defined(L_fract) && FROM_TYPE == 3 && TO_TYPE == 4 TO_FIXED_C_TYPE FRACT (FROM_FLOAT_C_TYPE a) { FROM_FLOAT_C_TYPE temp; TO_INT_C_TYPE z; TO_FIXED_C_TYPE c; temp = a * BASE; z = (TO_INT_C_TYPE) temp; #if TO_HAVE_PADDING_BITS z = z << TO_PADDING_BITS; z = z >> TO_PADDING_BITS; #endif memcpy (&c, &z, TO_FIXED_SIZE); return c; } #endif /* defined(FRACT) && FROM_TYPE == 3 && TO_TYPE == 4 */ /* Float -> Fixed with saturation. */ #if defined(SATFRACT) && defined(L_satfract) && FROM_TYPE == 3 && TO_TYPE == 4 TO_FIXED_C_TYPE SATFRACT (FROM_FLOAT_C_TYPE a) { FROM_FLOAT_C_TYPE temp; TO_INT_C_TYPE z; TO_FIXED_C_TYPE c; if (a >= FIXED_MAX) { #if TO_MODE_UNSIGNED == 0 || TO_HAVE_PADDING_BITS z = (TO_INT_C_TYPE)1 << TO_I_F_BITS; z = z - 1; #else z = -1; #endif } else if (a <= FIXED_MIN) { #if TO_MODE_UNSIGNED == 0 z = (TO_INT_C_TYPE)1 << TO_I_F_BITS; #else z = 0; #endif } else { temp = a * BASE; z = (TO_INT_C_TYPE) temp; } #if TO_HAVE_PADDING_BITS z = z << TO_PADDING_BITS; z = z >> TO_PADDING_BITS; #endif memcpy (&c, &z, TO_FIXED_SIZE); return c; } #endif /* defined(SATFRACT) && FROM_TYPE == 3 && TO_TYPE == 4 */
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