+++ /dev/null
-/* Fixed-point arithmetic support.
- Copyright (C) 2006, 2007, 2008, 2009 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.
-
-You should have received a copy of the GNU General Public License
-along with GCC; see the file COPYING3. If not see
-<http://www.gnu.org/licenses/>. */
-
-#include "config.h"
-#include "system.h"
-#include "coretypes.h"
-#include "tm.h"
-#include "tree.h"
-#include "toplev.h"
-
-/* Compare two fixed objects for bitwise identity. */
-
-bool
-fixed_identical (const FIXED_VALUE_TYPE *a, const FIXED_VALUE_TYPE *b)
-{
- return (a->mode == b->mode
- && a->data.high == b->data.high
- && a->data.low == b->data.low);
-}
-
-/* Calculate a hash value. */
-
-unsigned int
-fixed_hash (const FIXED_VALUE_TYPE *f)
-{
- return (unsigned int) (f->data.low ^ f->data.high);
-}
-
-/* Define the enum code for the range of the fixed-point value. */
-enum fixed_value_range_code {
- FIXED_OK, /* The value is within the range. */
- FIXED_UNDERFLOW, /* The value is less than the minimum. */
- FIXED_GT_MAX_EPS, /* The value is greater than the maximum, but not equal
- to the maximum plus the epsilon. */
- FIXED_MAX_EPS /* The value equals the maximum plus the epsilon. */
-};
-
-/* Check REAL_VALUE against the range of the fixed-point mode.
- Return FIXED_OK, if it is within the range.
- FIXED_UNDERFLOW, if it is less than the minimum.
- FIXED_GT_MAX_EPS, if it is greater than the maximum, but not equal to
- the maximum plus the epsilon.
- FIXED_MAX_EPS, if it is equal to the maximum plus the epsilon. */
-
-static enum fixed_value_range_code
-check_real_for_fixed_mode (REAL_VALUE_TYPE *real_value, enum machine_mode mode)
-{
- REAL_VALUE_TYPE max_value, min_value, epsilon_value;
-
- real_2expN (&max_value, GET_MODE_IBIT (mode), mode);
- real_2expN (&epsilon_value, -GET_MODE_FBIT (mode), mode);
-
- if (SIGNED_FIXED_POINT_MODE_P (mode))
- min_value = REAL_VALUE_NEGATE (max_value);
- else
- real_from_string (&min_value, "0.0");
-
- if (real_compare (LT_EXPR, real_value, &min_value))
- return FIXED_UNDERFLOW;
- if (real_compare (EQ_EXPR, real_value, &max_value))
- return FIXED_MAX_EPS;
- real_arithmetic (&max_value, MINUS_EXPR, &max_value, &epsilon_value);
- if (real_compare (GT_EXPR, real_value, &max_value))
- return FIXED_GT_MAX_EPS;
- return FIXED_OK;
-}
-
-/* Initialize from a decimal or hexadecimal string. */
-
-void
-fixed_from_string (FIXED_VALUE_TYPE *f, const char *str, enum machine_mode mode)
-{
- REAL_VALUE_TYPE real_value, fixed_value, base_value;
- unsigned int fbit;
- enum fixed_value_range_code temp;
-
- f->mode = mode;
- fbit = GET_MODE_FBIT (mode);
-
- real_from_string (&real_value, str);
- temp = check_real_for_fixed_mode (&real_value, f->mode);
- /* We don't want to warn the case when the _Fract value is 1.0. */
- if (temp == FIXED_UNDERFLOW
- || temp == FIXED_GT_MAX_EPS
- || (temp == FIXED_MAX_EPS && ALL_ACCUM_MODE_P (f->mode)))
- warning (OPT_Woverflow,
- "large fixed-point constant implicitly truncated to fixed-point type");
- real_2expN (&base_value, fbit, mode);
- real_arithmetic (&fixed_value, MULT_EXPR, &real_value, &base_value);
- real_to_integer2 ((HOST_WIDE_INT *)&f->data.low, &f->data.high,
- &fixed_value);
-
- if (temp == FIXED_MAX_EPS && ALL_FRACT_MODE_P (f->mode))
- {
- /* From the spec, we need to evaluate 1 to the maximal value. */
- f->data.low = -1;
- f->data.high = -1;
- f->data = double_int_ext (f->data,
- GET_MODE_FBIT (f->mode)
- + GET_MODE_IBIT (f->mode), 1);
- }
- else
- f->data = double_int_ext (f->data,
- SIGNED_FIXED_POINT_MODE_P (f->mode)
- + GET_MODE_FBIT (f->mode)
- + GET_MODE_IBIT (f->mode),
- UNSIGNED_FIXED_POINT_MODE_P (f->mode));
-}
-
-/* Render F as a decimal floating point constant. */
-
-void
-fixed_to_decimal (char *str, const FIXED_VALUE_TYPE *f_orig,
- size_t buf_size)
-{
- REAL_VALUE_TYPE real_value, base_value, fixed_value;
-
- real_2expN (&base_value, GET_MODE_FBIT (f_orig->mode), f_orig->mode);
- real_from_integer (&real_value, VOIDmode, f_orig->data.low, f_orig->data.high,
- UNSIGNED_FIXED_POINT_MODE_P (f_orig->mode));
- real_arithmetic (&fixed_value, RDIV_EXPR, &real_value, &base_value);
- real_to_decimal (str, &fixed_value, buf_size, 0, 1);
-}
-
-/* If SAT_P, saturate A to the maximum or the minimum, and save to *F based on
- the machine mode MODE.
- Do not modify *F otherwise.
- This function assumes the width of double_int is greater than the width
- of the fixed-point value (the sum of a possible sign bit, possible ibits,
- and fbits).
- Return true, if !SAT_P and overflow. */
-
-static bool
-fixed_saturate1 (enum machine_mode mode, double_int a, double_int *f,
- bool sat_p)
-{
- bool overflow_p = false;
- bool unsigned_p = UNSIGNED_FIXED_POINT_MODE_P (mode);
- int i_f_bits = GET_MODE_IBIT (mode) + GET_MODE_FBIT (mode);
-
- if (unsigned_p) /* Unsigned type. */
- {
- double_int max;
- max.low = -1;
- max.high = -1;
- max = double_int_ext (max, i_f_bits, 1);
- if (double_int_cmp (a, max, 1) == 1)
- {
- if (sat_p)
- *f = max;
- else
- overflow_p = true;
- }
- }
- else /* Signed type. */
- {
- double_int max, min;
- max.high = -1;
- max.low = -1;
- max = double_int_ext (max, i_f_bits, 1);
- min.high = 0;
- min.low = 1;
- lshift_double (min.low, min.high, i_f_bits,
- 2 * HOST_BITS_PER_WIDE_INT,
- &min.low, &min.high, 1);
- min = double_int_ext (min, 1 + i_f_bits, 0);
- if (double_int_cmp (a, max, 0) == 1)
- {
- if (sat_p)
- *f = max;
- else
- overflow_p = true;
- }
- else if (double_int_cmp (a, min, 0) == -1)
- {
- if (sat_p)
- *f = min;
- else
- overflow_p = true;
- }
- }
- return overflow_p;
-}
-
-/* If SAT_P, saturate {A_HIGH, A_LOW} to the maximum or the minimum, and
- save to *F based on the machine mode MODE.
- Do not modify *F otherwise.
- This function assumes the width of two double_int is greater than the width
- of the fixed-point value (the sum of a possible sign bit, possible ibits,
- and fbits).
- Return true, if !SAT_P and overflow. */
-
-static bool
-fixed_saturate2 (enum machine_mode mode, double_int a_high, double_int a_low,
- double_int *f, bool sat_p)
-{
- bool overflow_p = false;
- bool unsigned_p = UNSIGNED_FIXED_POINT_MODE_P (mode);
- int i_f_bits = GET_MODE_IBIT (mode) + GET_MODE_FBIT (mode);
-
- if (unsigned_p) /* Unsigned type. */
- {
- double_int max_r, max_s;
- max_r.high = 0;
- max_r.low = 0;
- max_s.high = -1;
- max_s.low = -1;
- max_s = double_int_ext (max_s, i_f_bits, 1);
- if (double_int_cmp (a_high, max_r, 1) == 1
- || (double_int_equal_p (a_high, max_r) &&
- double_int_cmp (a_low, max_s, 1) == 1))
- {
- if (sat_p)
- *f = max_s;
- else
- overflow_p = true;
- }
- }
- else /* Signed type. */
- {
- double_int max_r, max_s, min_r, min_s;
- max_r.high = 0;
- max_r.low = 0;
- max_s.high = -1;
- max_s.low = -1;
- max_s = double_int_ext (max_s, i_f_bits, 1);
- min_r.high = -1;
- min_r.low = -1;
- min_s.high = 0;
- min_s.low = 1;
- lshift_double (min_s.low, min_s.high, i_f_bits,
- 2 * HOST_BITS_PER_WIDE_INT,
- &min_s.low, &min_s.high, 1);
- min_s = double_int_ext (min_s, 1 + i_f_bits, 0);
- if (double_int_cmp (a_high, max_r, 0) == 1
- || (double_int_equal_p (a_high, max_r) &&
- double_int_cmp (a_low, max_s, 1) == 1))
- {
- if (sat_p)
- *f = max_s;
- else
- overflow_p = true;
- }
- else if (double_int_cmp (a_high, min_r, 0) == -1
- || (double_int_equal_p (a_high, min_r) &&
- double_int_cmp (a_low, min_s, 1) == -1))
- {
- if (sat_p)
- *f = min_s;
- else
- overflow_p = true;
- }
- }
- return overflow_p;
-}
-
-/* Return the sign bit based on I_F_BITS. */
-
-static inline int
-get_fixed_sign_bit (double_int a, int i_f_bits)
-{
- if (i_f_bits < HOST_BITS_PER_WIDE_INT)
- return (a.low >> i_f_bits) & 1;
- else
- return (a.high >> (i_f_bits - HOST_BITS_PER_WIDE_INT)) & 1;
-}
-
-/* Calculate F = A + (SUBTRACT_P ? -B : B).
- If SAT_P, saturate the result to the max or the min.
- Return true, if !SAT_P and overflow. */
-
-static bool
-do_fixed_add (FIXED_VALUE_TYPE *f, const FIXED_VALUE_TYPE *a,
- const FIXED_VALUE_TYPE *b, bool subtract_p, bool sat_p)
-{
- bool overflow_p = false;
- bool unsigned_p;
- double_int temp;
- int i_f_bits;
-
- /* This was a conditional expression but it triggered a bug in
- Sun C 5.5. */
- if (subtract_p)
- temp = double_int_neg (b->data);
- else
- temp = b->data;
-
- unsigned_p = UNSIGNED_FIXED_POINT_MODE_P (a->mode);
- i_f_bits = GET_MODE_IBIT (a->mode) + GET_MODE_FBIT (a->mode);
- f->mode = a->mode;
- f->data = double_int_add (a->data, temp);
- if (unsigned_p) /* Unsigned type. */
- {
- if (subtract_p) /* Unsigned subtraction. */
- {
- if (double_int_cmp (a->data, b->data, 1) == -1)
- {
- if (sat_p)
- {
- f->data.high = 0;
- f->data.low = 0;
- }
- else
- overflow_p = true;
- }
- }
- else /* Unsigned addition. */
- {
- f->data = double_int_ext (f->data, i_f_bits, 1);
- if (double_int_cmp (f->data, a->data, 1) == -1
- || double_int_cmp (f->data, b->data, 1) == -1)
- {
- if (sat_p)
- {
- f->data.high = -1;
- f->data.low = -1;
- }
- else
- overflow_p = true;
- }
- }
- }
- else /* Signed type. */
- {
- if ((!subtract_p
- && (get_fixed_sign_bit (a->data, i_f_bits)
- == get_fixed_sign_bit (b->data, i_f_bits))
- && (get_fixed_sign_bit (a->data, i_f_bits)
- != get_fixed_sign_bit (f->data, i_f_bits)))
- || (subtract_p
- && (get_fixed_sign_bit (a->data, i_f_bits)
- != get_fixed_sign_bit (b->data, i_f_bits))
- && (get_fixed_sign_bit (a->data, i_f_bits)
- != get_fixed_sign_bit (f->data, i_f_bits))))
- {
- if (sat_p)
- {
- f->data.low = 1;
- f->data.high = 0;
- lshift_double (f->data.low, f->data.high, i_f_bits,
- 2 * HOST_BITS_PER_WIDE_INT,
- &f->data.low, &f->data.high, 1);
- if (get_fixed_sign_bit (a->data, i_f_bits) == 0)
- {
- double_int one;
- one.low = 1;
- one.high = 0;
- f->data = double_int_add (f->data, double_int_neg (one));
- }
- }
- else
- overflow_p = true;
- }
- }
- f->data = double_int_ext (f->data, (!unsigned_p) + i_f_bits, unsigned_p);
- return overflow_p;
-}
-
-/* Calculate F = A * B.
- If SAT_P, saturate the result to the max or the min.
- Return true, if !SAT_P and overflow. */
-
-static bool
-do_fixed_multiply (FIXED_VALUE_TYPE *f, const FIXED_VALUE_TYPE *a,
- const FIXED_VALUE_TYPE *b, bool sat_p)
-{
- bool overflow_p = false;
- bool unsigned_p = UNSIGNED_FIXED_POINT_MODE_P (a->mode);
- int i_f_bits = GET_MODE_IBIT (a->mode) + GET_MODE_FBIT (a->mode);
- f->mode = a->mode;
- if (GET_MODE_PRECISION (f->mode) <= HOST_BITS_PER_WIDE_INT)
- {
- f->data = double_int_mul (a->data, b->data);
- lshift_double (f->data.low, f->data.high,
- (-GET_MODE_FBIT (f->mode)),
- 2 * HOST_BITS_PER_WIDE_INT,
- &f->data.low, &f->data.high, !unsigned_p);
- overflow_p = fixed_saturate1 (f->mode, f->data, &f->data, sat_p);
- }
- else
- {
- /* The result of multiplication expands to two double_int. */
- double_int a_high, a_low, b_high, b_low;
- double_int high_high, high_low, low_high, low_low;
- double_int r, s, temp1, temp2;
- int carry = 0;
-
- /* Decompose a and b to four double_int. */
- a_high.low = a->data.high;
- a_high.high = 0;
- a_low.low = a->data.low;
- a_low.high = 0;
- b_high.low = b->data.high;
- b_high.high = 0;
- b_low.low = b->data.low;
- b_low.high = 0;
-
- /* Perform four multiplications. */
- low_low = double_int_mul (a_low, b_low);
- low_high = double_int_mul (a_low, b_high);
- high_low = double_int_mul (a_high, b_low);
- high_high = double_int_mul (a_high, b_high);
-
- /* Accumulate four results to {r, s}. */
- temp1.high = high_low.low;
- temp1.low = 0;
- s = double_int_add (low_low, temp1);
- if (double_int_cmp (s, low_low, 1) == -1
- || double_int_cmp (s, temp1, 1) == -1)
- carry ++; /* Carry */
- temp1.high = s.high;
- temp1.low = s.low;
- temp2.high = low_high.low;
- temp2.low = 0;
- s = double_int_add (temp1, temp2);
- if (double_int_cmp (s, temp1, 1) == -1
- || double_int_cmp (s, temp2, 1) == -1)
- carry ++; /* Carry */
-
- temp1.low = high_low.high;
- temp1.high = 0;
- r = double_int_add (high_high, temp1);
- temp1.low = low_high.high;
- temp1.high = 0;
- r = double_int_add (r, temp1);
- temp1.low = carry;
- temp1.high = 0;
- r = double_int_add (r, temp1);
-
- /* We need to add neg(b) to r, if a < 0. */
- if (!unsigned_p && a->data.high < 0)
- r = double_int_add (r, double_int_neg (b->data));
- /* We need to add neg(a) to r, if b < 0. */
- if (!unsigned_p && b->data.high < 0)
- r = double_int_add (r, double_int_neg (a->data));
-
- /* Shift right the result by FBIT. */
- if (GET_MODE_FBIT (f->mode) == 2 * HOST_BITS_PER_WIDE_INT)
- {
- s.low = r.low;
- s.high = r.high;
- if (unsigned_p)
- {
- r.low = 0;
- r.high = 0;
- }
- else
- {
- r.low = -1;
- r.high = -1;
- }
- f->data.low = s.low;
- f->data.high = s.high;
- }
- else
- {
- lshift_double (s.low, s.high,
- (-GET_MODE_FBIT (f->mode)),
- 2 * HOST_BITS_PER_WIDE_INT,
- &s.low, &s.high, 0);
- lshift_double (r.low, r.high,
- (2 * HOST_BITS_PER_WIDE_INT
- - GET_MODE_FBIT (f->mode)),
- 2 * HOST_BITS_PER_WIDE_INT,
- &f->data.low, &f->data.high, 0);
- f->data.low = f->data.low | s.low;
- f->data.high = f->data.high | s.high;
- s.low = f->data.low;
- s.high = f->data.high;
- lshift_double (r.low, r.high,
- (-GET_MODE_FBIT (f->mode)),
- 2 * HOST_BITS_PER_WIDE_INT,
- &r.low, &r.high, !unsigned_p);
- }
-
- overflow_p = fixed_saturate2 (f->mode, r, s, &f->data, sat_p);
- }
-
- f->data = double_int_ext (f->data, (!unsigned_p) + i_f_bits, unsigned_p);
- return overflow_p;
-}
-
-/* Calculate F = A / B.
- If SAT_P, saturate the result to the max or the min.
- Return true, if !SAT_P and overflow. */
-
-static bool
-do_fixed_divide (FIXED_VALUE_TYPE *f, const FIXED_VALUE_TYPE *a,
- const FIXED_VALUE_TYPE *b, bool sat_p)
-{
- bool overflow_p = false;
- bool unsigned_p = UNSIGNED_FIXED_POINT_MODE_P (a->mode);
- int i_f_bits = GET_MODE_IBIT (a->mode) + GET_MODE_FBIT (a->mode);
- f->mode = a->mode;
- if (GET_MODE_PRECISION (f->mode) <= HOST_BITS_PER_WIDE_INT)
- {
- lshift_double (a->data.low, a->data.high,
- GET_MODE_FBIT (f->mode),
- 2 * HOST_BITS_PER_WIDE_INT,
- &f->data.low, &f->data.high, !unsigned_p);
- f->data = double_int_div (f->data, b->data, unsigned_p, TRUNC_DIV_EXPR);
- overflow_p = fixed_saturate1 (f->mode, f->data, &f->data, sat_p);
- }
- else
- {
- double_int pos_a, pos_b, r, s;
- double_int quo_r, quo_s, mod, temp;
- int num_of_neg = 0;
- int i;
-
- /* If a < 0, negate a. */
- if (!unsigned_p && a->data.high < 0)
- {
- pos_a = double_int_neg (a->data);
- num_of_neg ++;
- }
- else
- pos_a = a->data;
-
- /* If b < 0, negate b. */
- if (!unsigned_p && b->data.high < 0)
- {
- pos_b = double_int_neg (b->data);
- num_of_neg ++;
- }
- else
- pos_b = b->data;
-
- /* Left shift pos_a to {r, s} by FBIT. */
- if (GET_MODE_FBIT (f->mode) == 2 * HOST_BITS_PER_WIDE_INT)
- {
- r = pos_a;
- s.high = 0;
- s.low = 0;
- }
- else
- {
- lshift_double (pos_a.low, pos_a.high,
- GET_MODE_FBIT (f->mode),
- 2 * HOST_BITS_PER_WIDE_INT,
- &s.low, &s.high, 0);
- lshift_double (pos_a.low, pos_a.high,
- - (2 * HOST_BITS_PER_WIDE_INT
- - GET_MODE_FBIT (f->mode)),
- 2 * HOST_BITS_PER_WIDE_INT,
- &r.low, &r.high, 0);
- }
-
- /* Divide r by pos_b to quo_r. The remainder is in mod. */
- div_and_round_double (TRUNC_DIV_EXPR, 1, r.low, r.high, pos_b.low,
- pos_b.high, &quo_r.low, &quo_r.high, &mod.low,
- &mod.high);
-
- quo_s.high = 0;
- quo_s.low = 0;
-
- for (i = 0; i < 2 * HOST_BITS_PER_WIDE_INT; i++)
- {
- /* Record the leftmost bit of mod. */
- int leftmost_mod = (mod.high < 0);
-
- /* Shift left mod by 1 bit. */
- lshift_double (mod.low, mod.high, 1, 2 * HOST_BITS_PER_WIDE_INT,
- &mod.low, &mod.high, 0);
-
- /* Test the leftmost bit of s to add to mod. */
- if (s.high < 0)
- mod.low += 1;
-
- /* Shift left quo_s by 1 bit. */
- lshift_double (quo_s.low, quo_s.high, 1, 2 * HOST_BITS_PER_WIDE_INT,
- &quo_s.low, &quo_s.high, 0);
-
- /* Try to calculate (mod - pos_b). */
- temp = double_int_add (mod, double_int_neg (pos_b));
-
- if (leftmost_mod == 1 || double_int_cmp (mod, pos_b, 1) != -1)
- {
- quo_s.low += 1;
- mod = temp;
- }
-
- /* Shift left s by 1 bit. */
- lshift_double (s.low, s.high, 1, 2 * HOST_BITS_PER_WIDE_INT,
- &s.low, &s.high, 0);
-
- }
-
- if (num_of_neg == 1)
- {
- quo_s = double_int_neg (quo_s);
- if (quo_s.high == 0 && quo_s.low == 0)
- quo_r = double_int_neg (quo_r);
- else
- {
- quo_r.low = ~quo_r.low;
- quo_r.high = ~quo_r.high;
- }
- }
-
- f->data = quo_s;
- overflow_p = fixed_saturate2 (f->mode, quo_r, quo_s, &f->data, sat_p);
- }
-
- f->data = double_int_ext (f->data, (!unsigned_p) + i_f_bits, unsigned_p);
- return overflow_p;
-}
-
-/* Calculate F = A << B if LEFT_P. Otherwise, F = A >> B.
- If SAT_P, saturate the result to the max or the min.
- Return true, if !SAT_P and overflow. */
-
-static bool
-do_fixed_shift (FIXED_VALUE_TYPE *f, const FIXED_VALUE_TYPE *a,
- const FIXED_VALUE_TYPE *b, bool left_p, bool sat_p)
-{
- bool overflow_p = false;
- bool unsigned_p = UNSIGNED_FIXED_POINT_MODE_P (a->mode);
- int i_f_bits = GET_MODE_IBIT (a->mode) + GET_MODE_FBIT (a->mode);
- f->mode = a->mode;
-
- if (b->data.low == 0)
- {
- f->data = a->data;
- return overflow_p;
- }
-
- if (GET_MODE_PRECISION (f->mode) <= HOST_BITS_PER_WIDE_INT || (!left_p))
- {
- lshift_double (a->data.low, a->data.high,
- left_p ? b->data.low : (-b->data.low),
- 2 * HOST_BITS_PER_WIDE_INT,
- &f->data.low, &f->data.high, !unsigned_p);
- if (left_p) /* Only left shift saturates. */
- overflow_p = fixed_saturate1 (f->mode, f->data, &f->data, sat_p);
- }
- else /* We need two double_int to store the left-shift result. */
- {
- double_int temp_high, temp_low;
- if (b->data.low == 2 * HOST_BITS_PER_WIDE_INT)
- {
- temp_high = a->data;
- temp_low.high = 0;
- temp_low.low = 0;
- }
- else
- {
- lshift_double (a->data.low, a->data.high,
- b->data.low,
- 2 * HOST_BITS_PER_WIDE_INT,
- &temp_low.low, &temp_low.high, !unsigned_p);
- /* Logical shift right to temp_high. */
- lshift_double (a->data.low, a->data.high,
- b->data.low - 2 * HOST_BITS_PER_WIDE_INT,
- 2 * HOST_BITS_PER_WIDE_INT,
- &temp_high.low, &temp_high.high, 0);
- }
- if (!unsigned_p && a->data.high < 0) /* Signed-extend temp_high. */
- temp_high = double_int_ext (temp_high, b->data.low, unsigned_p);
- f->data = temp_low;
- overflow_p = fixed_saturate2 (f->mode, temp_high, temp_low, &f->data,
- sat_p);
- }
- f->data = double_int_ext (f->data, (!unsigned_p) + i_f_bits, unsigned_p);
- return overflow_p;
-}
-
-/* Calculate F = -A.
- If SAT_P, saturate the result to the max or the min.
- Return true, if !SAT_P and overflow. */
-
-static bool
-do_fixed_neg (FIXED_VALUE_TYPE *f, const FIXED_VALUE_TYPE *a, bool sat_p)
-{
- bool overflow_p = false;
- bool unsigned_p = UNSIGNED_FIXED_POINT_MODE_P (a->mode);
- int i_f_bits = GET_MODE_IBIT (a->mode) + GET_MODE_FBIT (a->mode);
- f->mode = a->mode;
- f->data = double_int_neg (a->data);
- f->data = double_int_ext (f->data, (!unsigned_p) + i_f_bits, unsigned_p);
-
- if (unsigned_p) /* Unsigned type. */
- {
- if (f->data.low != 0 || f->data.high != 0)
- {
- if (sat_p)
- {
- f->data.low = 0;
- f->data.high = 0;
- }
- else
- overflow_p = true;
- }
- }
- else /* Signed type. */
- {
- if (!(f->data.high == 0 && f->data.low == 0)
- && f->data.high == a->data.high && f->data.low == a->data.low )
- {
- if (sat_p)
- {
- /* Saturate to the maximum by subtracting f->data by one. */
- f->data.low = -1;
- f->data.high = -1;
- f->data = double_int_ext (f->data, i_f_bits, 1);
- }
- else
- overflow_p = true;
- }
- }
- return overflow_p;
-}
-
-/* Perform the binary or unary operation described by CODE.
- Note that OP0 and OP1 must have the same mode for binary operators.
- For a unary operation, leave OP1 NULL.
- Return true, if !SAT_P and overflow. */
-
-bool
-fixed_arithmetic (FIXED_VALUE_TYPE *f, int icode, const FIXED_VALUE_TYPE *op0,
- const FIXED_VALUE_TYPE *op1, bool sat_p)
-{
- switch (icode)
- {
- case NEGATE_EXPR:
- return do_fixed_neg (f, op0, sat_p);
- break;
-
- case PLUS_EXPR:
- gcc_assert (op0->mode == op1->mode);
- return do_fixed_add (f, op0, op1, false, sat_p);
- break;
-
- case MINUS_EXPR:
- gcc_assert (op0->mode == op1->mode);
- return do_fixed_add (f, op0, op1, true, sat_p);
- break;
-
- case MULT_EXPR:
- gcc_assert (op0->mode == op1->mode);
- return do_fixed_multiply (f, op0, op1, sat_p);
- break;
-
- case TRUNC_DIV_EXPR:
- gcc_assert (op0->mode == op1->mode);
- return do_fixed_divide (f, op0, op1, sat_p);
- break;
-
- case LSHIFT_EXPR:
- return do_fixed_shift (f, op0, op1, true, sat_p);
- break;
-
- case RSHIFT_EXPR:
- return do_fixed_shift (f, op0, op1, false, sat_p);
- break;
-
- default:
- gcc_unreachable ();
- }
- return false;
-}
-
-/* Compare fixed-point values by tree_code.
- Note that OP0 and OP1 must have the same mode. */
-
-bool
-fixed_compare (int icode, const FIXED_VALUE_TYPE *op0,
- const FIXED_VALUE_TYPE *op1)
-{
- enum tree_code code = (enum tree_code) icode;
- gcc_assert (op0->mode == op1->mode);
-
- switch (code)
- {
- case NE_EXPR:
- return !double_int_equal_p (op0->data, op1->data);
-
- case EQ_EXPR:
- return double_int_equal_p (op0->data, op1->data);
-
- case LT_EXPR:
- return double_int_cmp (op0->data, op1->data,
- UNSIGNED_FIXED_POINT_MODE_P (op0->mode)) == -1;
-
- case LE_EXPR:
- return double_int_cmp (op0->data, op1->data,
- UNSIGNED_FIXED_POINT_MODE_P (op0->mode)) != 1;
-
- case GT_EXPR:
- return double_int_cmp (op0->data, op1->data,
- UNSIGNED_FIXED_POINT_MODE_P (op0->mode)) == 1;
-
- case GE_EXPR:
- return double_int_cmp (op0->data, op1->data,
- UNSIGNED_FIXED_POINT_MODE_P (op0->mode)) != -1;
-
- default:
- gcc_unreachable ();
- }
-}
-
-/* Extend or truncate to a new mode.
- If SAT_P, saturate the result to the max or the min.
- Return true, if !SAT_P and overflow. */
-
-bool
-fixed_convert (FIXED_VALUE_TYPE *f, enum machine_mode mode,
- const FIXED_VALUE_TYPE *a, bool sat_p)
-{
- bool overflow_p = false;
- if (mode == a->mode)
- {
- *f = *a;
- return overflow_p;
- }
-
- if (GET_MODE_FBIT (mode) > GET_MODE_FBIT (a->mode))
- {
- /* Left shift a to temp_high, temp_low based on a->mode. */
- double_int temp_high, temp_low;
- int amount = GET_MODE_FBIT (mode) - GET_MODE_FBIT (a->mode);
- lshift_double (a->data.low, a->data.high,
- amount,
- 2 * HOST_BITS_PER_WIDE_INT,
- &temp_low.low, &temp_low.high,
- SIGNED_FIXED_POINT_MODE_P (a->mode));
- /* Logical shift right to temp_high. */
- lshift_double (a->data.low, a->data.high,
- amount - 2 * HOST_BITS_PER_WIDE_INT,
- 2 * HOST_BITS_PER_WIDE_INT,
- &temp_high.low, &temp_high.high, 0);
- if (SIGNED_FIXED_POINT_MODE_P (a->mode)
- && a->data.high < 0) /* Signed-extend temp_high. */
- temp_high = double_int_ext (temp_high, amount, 0);
- f->mode = mode;
- f->data = temp_low;
- if (SIGNED_FIXED_POINT_MODE_P (a->mode) ==
- SIGNED_FIXED_POINT_MODE_P (f->mode))
- overflow_p = fixed_saturate2 (f->mode, temp_high, temp_low, &f->data,
- sat_p);
- else
- {
- /* Take care of the cases when converting between signed and
- unsigned. */
- if (SIGNED_FIXED_POINT_MODE_P (a->mode))
- {
- /* Signed -> Unsigned. */
- if (a->data.high < 0)
- {
- if (sat_p)
- {
- f->data.low = 0; /* Set to zero. */
- f->data.high = 0; /* Set to zero. */
- }
- else
- overflow_p = true;
- }
- else
- overflow_p = fixed_saturate2 (f->mode, temp_high, temp_low,
- &f->data, sat_p);
- }
- else
- {
- /* Unsigned -> Signed. */
- if (temp_high.high < 0)
- {
- if (sat_p)
- {
- /* Set to maximum. */
- f->data.low = -1; /* Set to all ones. */
- f->data.high = -1; /* Set to all ones. */
- f->data = double_int_ext (f->data,
- GET_MODE_FBIT (f->mode)
- + GET_MODE_IBIT (f->mode),
- 1); /* Clear the sign. */
- }
- else
- overflow_p = true;
- }
- else
- overflow_p = fixed_saturate2 (f->mode, temp_high, temp_low,
- &f->data, sat_p);
- }
- }
- }
- else
- {
- /* Right shift a to temp based on a->mode. */
- double_int temp;
- lshift_double (a->data.low, a->data.high,
- GET_MODE_FBIT (mode) - GET_MODE_FBIT (a->mode),
- 2 * HOST_BITS_PER_WIDE_INT,
- &temp.low, &temp.high,
- SIGNED_FIXED_POINT_MODE_P (a->mode));
- f->mode = mode;
- f->data = temp;
- if (SIGNED_FIXED_POINT_MODE_P (a->mode) ==
- SIGNED_FIXED_POINT_MODE_P (f->mode))
- overflow_p = fixed_saturate1 (f->mode, f->data, &f->data, sat_p);
- else
- {
- /* Take care of the cases when converting between signed and
- unsigned. */
- if (SIGNED_FIXED_POINT_MODE_P (a->mode))
- {
- /* Signed -> Unsigned. */
- if (a->data.high < 0)
- {
- if (sat_p)
- {
- f->data.low = 0; /* Set to zero. */
- f->data.high = 0; /* Set to zero. */
- }
- else
- overflow_p = true;
- }
- else
- overflow_p = fixed_saturate1 (f->mode, f->data, &f->data,
- sat_p);
- }
- else
- {
- /* Unsigned -> Signed. */
- if (temp.high < 0)
- {
- if (sat_p)
- {
- /* Set to maximum. */
- f->data.low = -1; /* Set to all ones. */
- f->data.high = -1; /* Set to all ones. */
- f->data = double_int_ext (f->data,
- GET_MODE_FBIT (f->mode)
- + GET_MODE_IBIT (f->mode),
- 1); /* Clear the sign. */
- }
- else
- overflow_p = true;
- }
- else
- overflow_p = fixed_saturate1 (f->mode, f->data, &f->data,
- sat_p);
- }
- }
- }
-
- f->data = double_int_ext (f->data,
- SIGNED_FIXED_POINT_MODE_P (f->mode)
- + GET_MODE_FBIT (f->mode)
- + GET_MODE_IBIT (f->mode),
- UNSIGNED_FIXED_POINT_MODE_P (f->mode));
- return overflow_p;
-}
-
-/* Convert to a new fixed-point mode from an integer.
- If UNSIGNED_P, this integer is unsigned.
- If SAT_P, saturate the result to the max or the min.
- Return true, if !SAT_P and overflow. */
-
-bool
-fixed_convert_from_int (FIXED_VALUE_TYPE *f, enum machine_mode mode,
- double_int a, bool unsigned_p, bool sat_p)
-{
- bool overflow_p = false;
- /* Left shift a to temp_high, temp_low. */
- double_int temp_high, temp_low;
- int amount = GET_MODE_FBIT (mode);
- if (amount == 2 * HOST_BITS_PER_WIDE_INT)
- {
- temp_high = a;
- temp_low.low = 0;
- temp_low.high = 0;
- }
- else
- {
- lshift_double (a.low, a.high,
- amount,
- 2 * HOST_BITS_PER_WIDE_INT,
- &temp_low.low, &temp_low.high, 0);
-
- /* Logical shift right to temp_high. */
- lshift_double (a.low, a.high,
- amount - 2 * HOST_BITS_PER_WIDE_INT,
- 2 * HOST_BITS_PER_WIDE_INT,
- &temp_high.low, &temp_high.high, 0);
- }
- if (!unsigned_p && a.high < 0) /* Signed-extend temp_high. */
- temp_high = double_int_ext (temp_high, amount, 0);
-
- f->mode = mode;
- f->data = temp_low;
-
- if (unsigned_p == UNSIGNED_FIXED_POINT_MODE_P (f->mode))
- overflow_p = fixed_saturate2 (f->mode, temp_high, temp_low, &f->data,
- sat_p);
- else
- {
- /* Take care of the cases when converting between signed and unsigned. */
- if (!unsigned_p)
- {
- /* Signed -> Unsigned. */
- if (a.high < 0)
- {
- if (sat_p)
- {
- f->data.low = 0; /* Set to zero. */
- f->data.high = 0; /* Set to zero. */
- }
- else
- overflow_p = true;
- }
- else
- overflow_p = fixed_saturate2 (f->mode, temp_high, temp_low,
- &f->data, sat_p);
- }
- else
- {
- /* Unsigned -> Signed. */
- if (temp_high.high < 0)
- {
- if (sat_p)
- {
- /* Set to maximum. */
- f->data.low = -1; /* Set to all ones. */
- f->data.high = -1; /* Set to all ones. */
- f->data = double_int_ext (f->data,
- GET_MODE_FBIT (f->mode)
- + GET_MODE_IBIT (f->mode),
- 1); /* Clear the sign. */
- }
- else
- overflow_p = true;
- }
- else
- overflow_p = fixed_saturate2 (f->mode, temp_high, temp_low,
- &f->data, sat_p);
- }
- }
- f->data = double_int_ext (f->data,
- SIGNED_FIXED_POINT_MODE_P (f->mode)
- + GET_MODE_FBIT (f->mode)
- + GET_MODE_IBIT (f->mode),
- UNSIGNED_FIXED_POINT_MODE_P (f->mode));
- return overflow_p;
-}
-
-/* Convert to a new fixed-point mode from a real.
- If SAT_P, saturate the result to the max or the min.
- Return true, if !SAT_P and overflow. */
-
-bool
-fixed_convert_from_real (FIXED_VALUE_TYPE *f, enum machine_mode mode,
- const REAL_VALUE_TYPE *a, bool sat_p)
-{
- bool overflow_p = false;
- REAL_VALUE_TYPE real_value, fixed_value, base_value;
- bool unsigned_p = UNSIGNED_FIXED_POINT_MODE_P (mode);
- int i_f_bits = GET_MODE_IBIT (mode) + GET_MODE_FBIT (mode);
- unsigned int fbit = GET_MODE_FBIT (mode);
- enum fixed_value_range_code temp;
-
- real_value = *a;
- f->mode = mode;
- real_2expN (&base_value, fbit, mode);
- real_arithmetic (&fixed_value, MULT_EXPR, &real_value, &base_value);
- real_to_integer2 ((HOST_WIDE_INT *)&f->data.low, &f->data.high, &fixed_value);
- temp = check_real_for_fixed_mode (&real_value, mode);
- if (temp == FIXED_UNDERFLOW) /* Minimum. */
- {
- if (sat_p)
- {
- if (unsigned_p)
- {
- f->data.low = 0;
- f->data.high = 0;
- }
- else
- {
- f->data.low = 1;
- f->data.high = 0;
- lshift_double (f->data.low, f->data.high, i_f_bits,
- 2 * HOST_BITS_PER_WIDE_INT,
- &f->data.low, &f->data.high, 1);
- f->data = double_int_ext (f->data, 1 + i_f_bits, 0);
- }
- }
- else
- overflow_p = true;
- }
- else if (temp == FIXED_GT_MAX_EPS || temp == FIXED_MAX_EPS) /* Maximum. */
- {
- if (sat_p)
- {
- f->data.low = -1;
- f->data.high = -1;
- f->data = double_int_ext (f->data, i_f_bits, 1);
- }
- else
- overflow_p = true;
- }
- f->data = double_int_ext (f->data, (!unsigned_p) + i_f_bits, unsigned_p);
- return overflow_p;
-}
-
-/* Convert to a new real mode from a fixed-point. */
-
-void
-real_convert_from_fixed (REAL_VALUE_TYPE *r, enum machine_mode mode,
- const FIXED_VALUE_TYPE *f)
-{
- REAL_VALUE_TYPE base_value, fixed_value, real_value;
-
- real_2expN (&base_value, GET_MODE_FBIT (f->mode), f->mode);
- real_from_integer (&fixed_value, VOIDmode, f->data.low, f->data.high,
- UNSIGNED_FIXED_POINT_MODE_P (f->mode));
- real_arithmetic (&real_value, RDIV_EXPR, &fixed_value, &base_value);
- real_convert (r, mode, &real_value);
-}
-
-/* Determine whether a fixed-point value F is negative. */
-
-bool
-fixed_isneg (const FIXED_VALUE_TYPE *f)
-{
- if (SIGNED_FIXED_POINT_MODE_P (f->mode))
- {
- int i_f_bits = GET_MODE_IBIT (f->mode) + GET_MODE_FBIT (f->mode);
- int sign_bit = get_fixed_sign_bit (f->data, i_f_bits);
- if (sign_bit == 1)
- return true;
- }
-
- return false;
-}
projects / thirdparty / gcc.git / blobdiff