blob: fcf4a14ebaa75ca3a8fb4e4df83a724a79769140 [file] [log] [blame]
/* Constant folding for calls to built-in and internal functions.
Copyright (C) 1988-2018 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 "realmpfr.h"
#include "tree.h"
#include "stor-layout.h"
#include "options.h"
#include "fold-const.h"
#include "fold-const-call.h"
#include "case-cfn-macros.h"
#include "tm.h" /* For C[LT]Z_DEFINED_AT_ZERO. */
#include "builtins.h"
#include "gimple-expr.h"
/* Functions that test for certain constant types, abstracting away the
decision about whether to check for overflow. */
static inline bool
integer_cst_p (tree t)
{
return TREE_CODE (t) == INTEGER_CST && !TREE_OVERFLOW (t);
}
static inline bool
real_cst_p (tree t)
{
return TREE_CODE (t) == REAL_CST && !TREE_OVERFLOW (t);
}
static inline bool
complex_cst_p (tree t)
{
return TREE_CODE (t) == COMPLEX_CST;
}
/* Return true if ARG is a constant in the range of the host size_t.
Store it in *SIZE_OUT if so. */
static inline bool
host_size_t_cst_p (tree t, size_t *size_out)
{
if (types_compatible_p (size_type_node, TREE_TYPE (t))
&& integer_cst_p (t)
&& (wi::min_precision (wi::to_wide (t), UNSIGNED)
<= sizeof (size_t) * CHAR_BIT))
{
*size_out = tree_to_uhwi (t);
return true;
}
return false;
}
/* RES is the result of a comparison in which < 0 means "less", 0 means
"equal" and > 0 means "more". Canonicalize it to -1, 0 or 1 and
return it in type TYPE. */
tree
build_cmp_result (tree type, int res)
{
return build_int_cst (type, res < 0 ? -1 : res > 0 ? 1 : 0);
}
/* M is the result of trying to constant-fold an expression (starting
with clear MPFR flags) and INEXACT says whether the result in M is
exact or inexact. Return true if M can be used as a constant-folded
result in format FORMAT, storing the value in *RESULT if so. */
static bool
do_mpfr_ckconv (real_value *result, mpfr_srcptr m, bool inexact,
const real_format *format)
{
/* Proceed iff we get a normal number, i.e. not NaN or Inf and no
overflow/underflow occurred. If -frounding-math, proceed iff the
result of calling FUNC was exact. */
if (!mpfr_number_p (m)
|| mpfr_overflow_p ()
|| mpfr_underflow_p ()
|| (flag_rounding_math && inexact))
return false;
REAL_VALUE_TYPE tmp;
real_from_mpfr (&tmp, m, format, GMP_RNDN);
/* Proceed iff GCC's REAL_VALUE_TYPE can hold the MPFR values.
If the REAL_VALUE_TYPE is zero but the mpft_t is not, then we
underflowed in the conversion. */
if (!real_isfinite (&tmp)
|| ((tmp.cl == rvc_zero) != (mpfr_zero_p (m) != 0)))
return false;
real_convert (result, format, &tmp);
return real_identical (result, &tmp);
}
/* Try to evaluate:
*RESULT = f (*ARG)
in format FORMAT, given that FUNC is the MPFR implementation of f.
Return true on success. */
static bool
do_mpfr_arg1 (real_value *result,
int (*func) (mpfr_ptr, mpfr_srcptr, mpfr_rnd_t),
const real_value *arg, const real_format *format)
{
/* To proceed, MPFR must exactly represent the target floating point
format, which only happens when the target base equals two. */
if (format->b != 2 || !real_isfinite (arg))
return false;
int prec = format->p;
mp_rnd_t rnd = format->round_towards_zero ? GMP_RNDZ : GMP_RNDN;
mpfr_t m;
mpfr_init2 (m, prec);
mpfr_from_real (m, arg, GMP_RNDN);
mpfr_clear_flags ();
bool inexact = func (m, m, rnd);
bool ok = do_mpfr_ckconv (result, m, inexact, format);
mpfr_clear (m);
return ok;
}
/* Try to evaluate:
*RESULT_SIN = sin (*ARG);
*RESULT_COS = cos (*ARG);
for format FORMAT. Return true on success. */
static bool
do_mpfr_sincos (real_value *result_sin, real_value *result_cos,
const real_value *arg, const real_format *format)
{
/* To proceed, MPFR must exactly represent the target floating point
format, which only happens when the target base equals two. */
if (format->b != 2 || !real_isfinite (arg))
return false;
int prec = format->p;
mp_rnd_t rnd = format->round_towards_zero ? GMP_RNDZ : GMP_RNDN;
mpfr_t m, ms, mc;
mpfr_inits2 (prec, m, ms, mc, NULL);
mpfr_from_real (m, arg, GMP_RNDN);
mpfr_clear_flags ();
bool inexact = mpfr_sin_cos (ms, mc, m, rnd);
bool ok = (do_mpfr_ckconv (result_sin, ms, inexact, format)
&& do_mpfr_ckconv (result_cos, mc, inexact, format));
mpfr_clears (m, ms, mc, NULL);
return ok;
}
/* Try to evaluate:
*RESULT = f (*ARG0, *ARG1)
in format FORMAT, given that FUNC is the MPFR implementation of f.
Return true on success. */
static bool
do_mpfr_arg2 (real_value *result,
int (*func) (mpfr_ptr, mpfr_srcptr, mpfr_srcptr, mpfr_rnd_t),
const real_value *arg0, const real_value *arg1,
const real_format *format)
{
/* To proceed, MPFR must exactly represent the target floating point
format, which only happens when the target base equals two. */
if (format->b != 2 || !real_isfinite (arg0) || !real_isfinite (arg1))
return false;
int prec = format->p;
mp_rnd_t rnd = format->round_towards_zero ? GMP_RNDZ : GMP_RNDN;
mpfr_t m0, m1;
mpfr_inits2 (prec, m0, m1, NULL);
mpfr_from_real (m0, arg0, GMP_RNDN);
mpfr_from_real (m1, arg1, GMP_RNDN);
mpfr_clear_flags ();
bool inexact = func (m0, m0, m1, rnd);
bool ok = do_mpfr_ckconv (result, m0, inexact, format);
mpfr_clears (m0, m1, NULL);
return ok;
}
/* Try to evaluate:
*RESULT = f (ARG0, *ARG1)
in format FORMAT, given that FUNC is the MPFR implementation of f.
Return true on success. */
static bool
do_mpfr_arg2 (real_value *result,
int (*func) (mpfr_ptr, long, mpfr_srcptr, mp_rnd_t),
const wide_int_ref &arg0, const real_value *arg1,
const real_format *format)
{
if (format->b != 2 || !real_isfinite (arg1))
return false;
int prec = format->p;
mp_rnd_t rnd = format->round_towards_zero ? GMP_RNDZ : GMP_RNDN;
mpfr_t m;
mpfr_init2 (m, prec);
mpfr_from_real (m, arg1, GMP_RNDN);
mpfr_clear_flags ();
bool inexact = func (m, arg0.to_shwi (), m, rnd);
bool ok = do_mpfr_ckconv (result, m, inexact, format);
mpfr_clear (m);
return ok;
}
/* Try to evaluate:
*RESULT = f (*ARG0, *ARG1, *ARG2)
in format FORMAT, given that FUNC is the MPFR implementation of f.
Return true on success. */
static bool
do_mpfr_arg3 (real_value *result,
int (*func) (mpfr_ptr, mpfr_srcptr, mpfr_srcptr,
mpfr_srcptr, mpfr_rnd_t),
const real_value *arg0, const real_value *arg1,
const real_value *arg2, const real_format *format)
{
/* To proceed, MPFR must exactly represent the target floating point
format, which only happens when the target base equals two. */
if (format->b != 2
|| !real_isfinite (arg0)
|| !real_isfinite (arg1)
|| !real_isfinite (arg2))
return false;
int prec = format->p;
mp_rnd_t rnd = format->round_towards_zero ? GMP_RNDZ : GMP_RNDN;
mpfr_t m0, m1, m2;
mpfr_inits2 (prec, m0, m1, m2, NULL);
mpfr_from_real (m0, arg0, GMP_RNDN);
mpfr_from_real (m1, arg1, GMP_RNDN);
mpfr_from_real (m2, arg2, GMP_RNDN);
mpfr_clear_flags ();
bool inexact = func (m0, m0, m1, m2, rnd);
bool ok = do_mpfr_ckconv (result, m0, inexact, format);
mpfr_clears (m0, m1, m2, NULL);
return ok;
}
/* M is the result of trying to constant-fold an expression (starting
with clear MPFR flags) and INEXACT says whether the result in M is
exact or inexact. Return true if M can be used as a constant-folded
result in which the real and imaginary parts have format FORMAT.
Store those parts in *RESULT_REAL and *RESULT_IMAG if so. */
static bool
do_mpc_ckconv (real_value *result_real, real_value *result_imag,
mpc_srcptr m, bool inexact, const real_format *format)
{
/* Proceed iff we get a normal number, i.e. not NaN or Inf and no
overflow/underflow occurred. If -frounding-math, proceed iff the
result of calling FUNC was exact. */
if (!mpfr_number_p (mpc_realref (m))
|| !mpfr_number_p (mpc_imagref (m))
|| mpfr_overflow_p ()
|| mpfr_underflow_p ()
|| (flag_rounding_math && inexact))
return false;
REAL_VALUE_TYPE tmp_real, tmp_imag;
real_from_mpfr (&tmp_real, mpc_realref (m), format, GMP_RNDN);
real_from_mpfr (&tmp_imag, mpc_imagref (m), format, GMP_RNDN);
/* Proceed iff GCC's REAL_VALUE_TYPE can hold the MPFR values.
If the REAL_VALUE_TYPE is zero but the mpft_t is not, then we
underflowed in the conversion. */
if (!real_isfinite (&tmp_real)
|| !real_isfinite (&tmp_imag)
|| (tmp_real.cl == rvc_zero) != (mpfr_zero_p (mpc_realref (m)) != 0)
|| (tmp_imag.cl == rvc_zero) != (mpfr_zero_p (mpc_imagref (m)) != 0))
return false;
real_convert (result_real, format, &tmp_real);
real_convert (result_imag, format, &tmp_imag);
return (real_identical (result_real, &tmp_real)
&& real_identical (result_imag, &tmp_imag));
}
/* Try to evaluate:
RESULT = f (ARG)
in format FORMAT, given that FUNC is the mpc implementation of f.
Return true on success. Both RESULT and ARG are represented as
real and imaginary pairs. */
static bool
do_mpc_arg1 (real_value *result_real, real_value *result_imag,
int (*func) (mpc_ptr, mpc_srcptr, mpc_rnd_t),
const real_value *arg_real, const real_value *arg_imag,
const real_format *format)
{
/* To proceed, MPFR must exactly represent the target floating point
format, which only happens when the target base equals two. */
if (format->b != 2
|| !real_isfinite (arg_real)
|| !real_isfinite (arg_imag))
return false;
int prec = format->p;
mpc_rnd_t crnd = format->round_towards_zero ? MPC_RNDZZ : MPC_RNDNN;
mpc_t m;
mpc_init2 (m, prec);
mpfr_from_real (mpc_realref (m), arg_real, GMP_RNDN);
mpfr_from_real (mpc_imagref (m), arg_imag, GMP_RNDN);
mpfr_clear_flags ();
bool inexact = func (m, m, crnd);
bool ok = do_mpc_ckconv (result_real, result_imag, m, inexact, format);
mpc_clear (m);
return ok;
}
/* Try to evaluate:
RESULT = f (ARG0, ARG1)
in format FORMAT, given that FUNC is the mpc implementation of f.
Return true on success. RESULT, ARG0 and ARG1 are represented as
real and imaginary pairs. */
static bool
do_mpc_arg2 (real_value *result_real, real_value *result_imag,
int (*func)(mpc_ptr, mpc_srcptr, mpc_srcptr, mpc_rnd_t),
const real_value *arg0_real, const real_value *arg0_imag,
const real_value *arg1_real, const real_value *arg1_imag,
const real_format *format)
{
if (!real_isfinite (arg0_real)
|| !real_isfinite (arg0_imag)
|| !real_isfinite (arg1_real)
|| !real_isfinite (arg1_imag))
return false;
int prec = format->p;
mpc_rnd_t crnd = format->round_towards_zero ? MPC_RNDZZ : MPC_RNDNN;
mpc_t m0, m1;
mpc_init2 (m0, prec);
mpc_init2 (m1, prec);
mpfr_from_real (mpc_realref (m0), arg0_real, GMP_RNDN);
mpfr_from_real (mpc_imagref (m0), arg0_imag, GMP_RNDN);
mpfr_from_real (mpc_realref (m1), arg1_real, GMP_RNDN);
mpfr_from_real (mpc_imagref (m1), arg1_imag, GMP_RNDN);
mpfr_clear_flags ();
bool inexact = func (m0, m0, m1, crnd);
bool ok = do_mpc_ckconv (result_real, result_imag, m0, inexact, format);
mpc_clear (m0);
mpc_clear (m1);
return ok;
}
/* Try to evaluate:
*RESULT = logb (*ARG)
in format FORMAT. Return true on success. */
static bool
fold_const_logb (real_value *result, const real_value *arg,
const real_format *format)
{
switch (arg->cl)
{
case rvc_nan:
/* If arg is +-NaN, then return it. */
*result = *arg;
return true;
case rvc_inf:
/* If arg is +-Inf, then return +Inf. */
*result = *arg;
result->sign = 0;
return true;
case rvc_zero:
/* Zero may set errno and/or raise an exception. */
return false;
case rvc_normal:
/* For normal numbers, proceed iff radix == 2. In GCC,
normalized significands are in the range [0.5, 1.0). We
want the exponent as if they were [1.0, 2.0) so get the
exponent and subtract 1. */
if (format->b == 2)
{
real_from_integer (result, format, REAL_EXP (arg) - 1, SIGNED);
return true;
}
return false;
}
gcc_unreachable ();
}
/* Try to evaluate:
*RESULT = significand (*ARG)
in format FORMAT. Return true on success. */
static bool
fold_const_significand (real_value *result, const real_value *arg,
const real_format *format)
{
switch (arg->cl)
{
case rvc_zero:
case rvc_nan:
case rvc_inf:
/* If arg is +-0, +-Inf or +-NaN, then return it. */
*result = *arg;
return true;
case rvc_normal:
/* For normal numbers, proceed iff radix == 2. */
if (format->b == 2)
{
*result = *arg;
/* In GCC, normalized significands are in the range [0.5, 1.0).
We want them to be [1.0, 2.0) so set the exponent to 1. */
SET_REAL_EXP (result, 1);
return true;
}
return false;
}
gcc_unreachable ();
}
/* Try to evaluate:
*RESULT = f (*ARG)
where FORMAT is the format of *ARG and PRECISION is the number of
significant bits in the result. Return true on success. */
static bool
fold_const_conversion (wide_int *result,
void (*fn) (real_value *, format_helper,
const real_value *),
const real_value *arg, unsigned int precision,
const real_format *format)
{
if (!real_isfinite (arg))
return false;
real_value rounded;
fn (&rounded, format, arg);
bool fail = false;
*result = real_to_integer (&rounded, &fail, precision);
return !fail;
}
/* Try to evaluate:
*RESULT = pow (*ARG0, *ARG1)
in format FORMAT. Return true on success. */
static bool
fold_const_pow (real_value *result, const real_value *arg0,
const real_value *arg1, const real_format *format)
{
if (do_mpfr_arg2 (result, mpfr_pow, arg0, arg1, format))
return true;
/* Check for an integer exponent. */
REAL_VALUE_TYPE cint1;
HOST_WIDE_INT n1 = real_to_integer (arg1);
real_from_integer (&cint1, VOIDmode, n1, SIGNED);
/* Attempt to evaluate pow at compile-time, unless this should
raise an exception. */
if (real_identical (arg1, &cint1)
&& (n1 > 0
|| (!flag_trapping_math && !flag_errno_math)
|| !real_equal (arg0, &dconst0)))
{
bool inexact = real_powi (result, format, arg0, n1);
/* Avoid the folding if flag_signaling_nans is on. */
if (flag_unsafe_math_optimizations
|| (!inexact
&& !(flag_signaling_nans
&& REAL_VALUE_ISSIGNALING_NAN (*arg0))))
return true;
}
return false;
}
/* Try to evaluate:
*RESULT = ldexp (*ARG0, ARG1)
in format FORMAT. Return true on success. */
static bool
fold_const_builtin_load_exponent (real_value *result, const real_value *arg0,
const wide_int_ref &arg1,
const real_format *format)
{
/* Bound the maximum adjustment to twice the range of the
mode's valid exponents. Use abs to ensure the range is
positive as a sanity check. */
int max_exp_adj = 2 * labs (format->emax - format->emin);
/* The requested adjustment must be inside this range. This
is a preliminary cap to avoid things like overflow, we
may still fail to compute the result for other reasons. */
if (wi::les_p (arg1, -max_exp_adj) || wi::ges_p (arg1, max_exp_adj))
return false;
/* Don't perform operation if we honor signaling NaNs and
operand is a signaling NaN. */
if (!flag_unsafe_math_optimizations
&& flag_signaling_nans
&& REAL_VALUE_ISSIGNALING_NAN (*arg0))
return false;
REAL_VALUE_TYPE initial_result;
real_ldexp (&initial_result, arg0, arg1.to_shwi ());
/* Ensure we didn't overflow. */
if (real_isinf (&initial_result))
return false;
/* Only proceed if the target mode can hold the
resulting value. */
*result = real_value_truncate (format, initial_result);
return real_equal (&initial_result, result);
}
/* Fold a call to __builtin_nan or __builtin_nans with argument ARG and
return type TYPE. QUIET is true if a quiet rather than signalling
NaN is required. */
static tree
fold_const_builtin_nan (tree type, tree arg, bool quiet)
{
REAL_VALUE_TYPE real;
const char *str = c_getstr (arg);
if (str && real_nan (&real, str, quiet, TYPE_MODE (type)))
return build_real (type, real);
return NULL_TREE;
}
/* Fold a call to IFN_REDUC_<CODE> (ARG), returning a value of type TYPE. */
static tree
fold_const_reduction (tree type, tree arg, tree_code code)
{
unsigned HOST_WIDE_INT nelts;
if (TREE_CODE (arg) != VECTOR_CST
|| !VECTOR_CST_NELTS (arg).is_constant (&nelts))
return NULL_TREE;
tree res = VECTOR_CST_ELT (arg, 0);
for (unsigned HOST_WIDE_INT i = 1; i < nelts; i++)
{
res = const_binop (code, type, res, VECTOR_CST_ELT (arg, i));
if (res == NULL_TREE || !CONSTANT_CLASS_P (res))
return NULL_TREE;
}
return res;
}
/* Try to evaluate:
*RESULT = FN (*ARG)
in format FORMAT. Return true on success. */
static bool
fold_const_call_ss (real_value *result, combined_fn fn,
const real_value *arg, const real_format *format)
{
switch (fn)
{
CASE_CFN_SQRT:
CASE_CFN_SQRT_FN:
return (real_compare (GE_EXPR, arg, &dconst0)
&& do_mpfr_arg1 (result, mpfr_sqrt, arg, format));
CASE_CFN_CBRT:
return do_mpfr_arg1 (result, mpfr_cbrt, arg, format);
CASE_CFN_ASIN:
return (real_compare (GE_EXPR, arg, &dconstm1)
&& real_compare (LE_EXPR, arg, &dconst1)
&& do_mpfr_arg1 (result, mpfr_asin, arg, format));
CASE_CFN_ACOS:
return (real_compare (GE_EXPR, arg, &dconstm1)
&& real_compare (LE_EXPR, arg, &dconst1)
&& do_mpfr_arg1 (result, mpfr_acos, arg, format));
CASE_CFN_ATAN:
return do_mpfr_arg1 (result, mpfr_atan, arg, format);
CASE_CFN_ASINH:
return do_mpfr_arg1 (result, mpfr_asinh, arg, format);
CASE_CFN_ACOSH:
return (real_compare (GE_EXPR, arg, &dconst1)
&& do_mpfr_arg1 (result, mpfr_acosh, arg, format));
CASE_CFN_ATANH:
return (real_compare (GE_EXPR, arg, &dconstm1)
&& real_compare (LE_EXPR, arg, &dconst1)
&& do_mpfr_arg1 (result, mpfr_atanh, arg, format));
CASE_CFN_SIN:
return do_mpfr_arg1 (result, mpfr_sin, arg, format);
CASE_CFN_COS:
return do_mpfr_arg1 (result, mpfr_cos, arg, format);
CASE_CFN_TAN:
return do_mpfr_arg1 (result, mpfr_tan, arg, format);
CASE_CFN_SINH:
return do_mpfr_arg1 (result, mpfr_sinh, arg, format);
CASE_CFN_COSH:
return do_mpfr_arg1 (result, mpfr_cosh, arg, format);
CASE_CFN_TANH:
return do_mpfr_arg1 (result, mpfr_tanh, arg, format);
CASE_CFN_ERF:
return do_mpfr_arg1 (result, mpfr_erf, arg, format);
CASE_CFN_ERFC:
return do_mpfr_arg1 (result, mpfr_erfc, arg, format);
CASE_CFN_TGAMMA:
return do_mpfr_arg1 (result, mpfr_gamma, arg, format);
CASE_CFN_EXP:
return do_mpfr_arg1 (result, mpfr_exp, arg, format);
CASE_CFN_EXP2:
return do_mpfr_arg1 (result, mpfr_exp2, arg, format);
CASE_CFN_EXP10:
CASE_CFN_POW10:
return do_mpfr_arg1 (result, mpfr_exp10, arg, format);
CASE_CFN_EXPM1:
return do_mpfr_arg1 (result, mpfr_expm1, arg, format);
CASE_CFN_LOG:
return (real_compare (GT_EXPR, arg, &dconst0)
&& do_mpfr_arg1 (result, mpfr_log, arg, format));
CASE_CFN_LOG2:
return (real_compare (GT_EXPR, arg, &dconst0)
&& do_mpfr_arg1 (result, mpfr_log2, arg, format));
CASE_CFN_LOG10:
return (real_compare (GT_EXPR, arg, &dconst0)
&& do_mpfr_arg1 (result, mpfr_log10, arg, format));
CASE_CFN_LOG1P:
return (real_compare (GT_EXPR, arg, &dconstm1)
&& do_mpfr_arg1 (result, mpfr_log1p, arg, format));
CASE_CFN_J0:
return do_mpfr_arg1 (result, mpfr_j0, arg, format);
CASE_CFN_J1:
return do_mpfr_arg1 (result, mpfr_j1, arg, format);
CASE_CFN_Y0:
return (real_compare (GT_EXPR, arg, &dconst0)
&& do_mpfr_arg1 (result, mpfr_y0, arg, format));
CASE_CFN_Y1:
return (real_compare (GT_EXPR, arg, &dconst0)
&& do_mpfr_arg1 (result, mpfr_y1, arg, format));
CASE_CFN_FLOOR:
CASE_CFN_FLOOR_FN:
if (!REAL_VALUE_ISNAN (*arg) || !flag_errno_math)
{
real_floor (result, format, arg);
return true;
}
return false;
CASE_CFN_CEIL:
CASE_CFN_CEIL_FN:
if (!REAL_VALUE_ISNAN (*arg) || !flag_errno_math)
{
real_ceil (result, format, arg);
return true;
}
return false;
CASE_CFN_TRUNC:
CASE_CFN_TRUNC_FN:
real_trunc (result, format, arg);
return true;
CASE_CFN_ROUND:
CASE_CFN_ROUND_FN:
if (!REAL_VALUE_ISNAN (*arg) || !flag_errno_math)
{
real_round (result, format, arg);
return true;
}
return false;
CASE_CFN_LOGB:
return fold_const_logb (result, arg, format);
CASE_CFN_SIGNIFICAND:
return fold_const_significand (result, arg, format);
default:
return false;
}
}
/* Try to evaluate:
*RESULT = FN (*ARG)
where FORMAT is the format of ARG and PRECISION is the number of
significant bits in the result. Return true on success. */
static bool
fold_const_call_ss (wide_int *result, combined_fn fn,
const real_value *arg, unsigned int precision,
const real_format *format)
{
switch (fn)
{
CASE_CFN_SIGNBIT:
if (real_isneg (arg))
*result = wi::one (precision);
else
*result = wi::zero (precision);
return true;
CASE_CFN_ILOGB:
/* For ilogb we don't know FP_ILOGB0, so only handle normal values.
Proceed iff radix == 2. In GCC, normalized significands are in
the range [0.5, 1.0). We want the exponent as if they were
[1.0, 2.0) so get the exponent and subtract 1. */
if (arg->cl == rvc_normal && format->b == 2)
{
*result = wi::shwi (REAL_EXP (arg) - 1, precision);
return true;
}
return false;
CASE_CFN_ICEIL:
CASE_CFN_LCEIL:
CASE_CFN_LLCEIL:
return fold_const_conversion (result, real_ceil, arg,
precision, format);
CASE_CFN_LFLOOR:
CASE_CFN_IFLOOR:
CASE_CFN_LLFLOOR:
return fold_const_conversion (result, real_floor, arg,
precision, format);
CASE_CFN_IROUND:
CASE_CFN_LROUND:
CASE_CFN_LLROUND:
return fold_const_conversion (result, real_round, arg,
precision, format);
CASE_CFN_IRINT:
CASE_CFN_LRINT:
CASE_CFN_LLRINT:
/* Not yet folded to a constant. */
return false;
CASE_CFN_FINITE:
case CFN_BUILT_IN_FINITED32:
case CFN_BUILT_IN_FINITED64:
case CFN_BUILT_IN_FINITED128:
case CFN_BUILT_IN_ISFINITE:
*result = wi::shwi (real_isfinite (arg) ? 1 : 0, precision);
return true;
CASE_CFN_ISINF:
case CFN_BUILT_IN_ISINFD32:
case CFN_BUILT_IN_ISINFD64:
case CFN_BUILT_IN_ISINFD128:
if (real_isinf (arg))
*result = wi::shwi (arg->sign ? -1 : 1, precision);
else
*result = wi::shwi (0, precision);
return true;
CASE_CFN_ISNAN:
case CFN_BUILT_IN_ISNAND32:
case CFN_BUILT_IN_ISNAND64:
case CFN_BUILT_IN_ISNAND128:
*result = wi::shwi (real_isnan (arg) ? 1 : 0, precision);
return true;
default:
return false;
}
}
/* Try to evaluate:
*RESULT = FN (ARG)
where ARG_TYPE is the type of ARG and PRECISION is the number of bits
in the result. Return true on success. */
static bool
fold_const_call_ss (wide_int *result, combined_fn fn, const wide_int_ref &arg,
unsigned int precision, tree arg_type)
{
switch (fn)
{
CASE_CFN_FFS:
*result = wi::shwi (wi::ffs (arg), precision);
return true;
CASE_CFN_CLZ:
{
int tmp;
if (wi::ne_p (arg, 0))
tmp = wi::clz (arg);
else if (!CLZ_DEFINED_VALUE_AT_ZERO (SCALAR_INT_TYPE_MODE (arg_type),
tmp))
tmp = TYPE_PRECISION (arg_type);
*result = wi::shwi (tmp, precision);
return true;
}
CASE_CFN_CTZ:
{
int tmp;
if (wi::ne_p (arg, 0))
tmp = wi::ctz (arg);
else if (!CTZ_DEFINED_VALUE_AT_ZERO (SCALAR_INT_TYPE_MODE (arg_type),
tmp))
tmp = TYPE_PRECISION (arg_type);
*result = wi::shwi (tmp, precision);
return true;
}
CASE_CFN_CLRSB:
*result = wi::shwi (wi::clrsb (arg), precision);
return true;
CASE_CFN_POPCOUNT:
*result = wi::shwi (wi::popcount (arg), precision);
return true;
CASE_CFN_PARITY:
*result = wi::shwi (wi::parity (arg), precision);
return true;
case CFN_BUILT_IN_BSWAP16:
case CFN_BUILT_IN_BSWAP32:
case CFN_BUILT_IN_BSWAP64:
*result = wide_int::from (arg, precision, TYPE_SIGN (arg_type)).bswap ();
return true;
default:
return false;
}
}
/* Try to evaluate:
RESULT = FN (*ARG)
where FORMAT is the format of ARG and of the real and imaginary parts
of RESULT, passed as RESULT_REAL and RESULT_IMAG respectively. Return
true on success. */
static bool
fold_const_call_cs (real_value *result_real, real_value *result_imag,
combined_fn fn, const real_value *arg,
const real_format *format)
{
switch (fn)
{
CASE_CFN_CEXPI:
/* cexpi(x+yi) = cos(x)+sin(y)*i. */
return do_mpfr_sincos (result_imag, result_real, arg, format);
default:
return false;
}
}
/* Try to evaluate:
*RESULT = fn (ARG)
where FORMAT is the format of RESULT and of the real and imaginary parts
of ARG, passed as ARG_REAL and ARG_IMAG respectively. Return true on
success. */
static bool
fold_const_call_sc (real_value *result, combined_fn fn,
const real_value *arg_real, const real_value *arg_imag,
const real_format *format)
{
switch (fn)
{
CASE_CFN_CABS:
return do_mpfr_arg2 (result, mpfr_hypot, arg_real, arg_imag, format);
default:
return false;
}
}
/* Try to evaluate:
RESULT = fn (ARG)
where FORMAT is the format of the real and imaginary parts of RESULT
(RESULT_REAL and RESULT_IMAG) and of ARG (ARG_REAL and ARG_IMAG).
Return true on success. */
static bool
fold_const_call_cc (real_value *result_real, real_value *result_imag,
combined_fn fn, const real_value *arg_real,
const real_value *arg_imag, const real_format *format)
{
switch (fn)
{
CASE_CFN_CCOS:
return do_mpc_arg1 (result_real, result_imag, mpc_cos,
arg_real, arg_imag, format);
CASE_CFN_CCOSH:
return do_mpc_arg1 (result_real, result_imag, mpc_cosh,
arg_real, arg_imag, format);
CASE_CFN_CPROJ:
if (real_isinf (arg_real) || real_isinf (arg_imag))
{
real_inf (result_real);
*result_imag = dconst0;
result_imag->sign = arg_imag->sign;
}
else
{
*result_real = *arg_real;
*result_imag = *arg_imag;
}
return true;
CASE_CFN_CSIN:
return do_mpc_arg1 (result_real, result_imag, mpc_sin,
arg_real, arg_imag, format);
CASE_CFN_CSINH:
return do_mpc_arg1 (result_real, result_imag, mpc_sinh,
arg_real, arg_imag, format);
CASE_CFN_CTAN:
return do_mpc_arg1 (result_real, result_imag, mpc_tan,
arg_real, arg_imag, format);
CASE_CFN_CTANH:
return do_mpc_arg1 (result_real, result_imag, mpc_tanh,
arg_real, arg_imag, format);
CASE_CFN_CLOG:
return do_mpc_arg1 (result_real, result_imag, mpc_log,
arg_real, arg_imag, format);
CASE_CFN_CSQRT:
return do_mpc_arg1 (result_real, result_imag, mpc_sqrt,
arg_real, arg_imag, format);
CASE_CFN_CASIN:
return do_mpc_arg1 (result_real, result_imag, mpc_asin,
arg_real, arg_imag, format);
CASE_CFN_CACOS:
return do_mpc_arg1 (result_real, result_imag, mpc_acos,
arg_real, arg_imag, format);
CASE_CFN_CATAN:
return do_mpc_arg1 (result_real, result_imag, mpc_atan,
arg_real, arg_imag, format);
CASE_CFN_CASINH:
return do_mpc_arg1 (result_real, result_imag, mpc_asinh,
arg_real, arg_imag, format);
CASE_CFN_CACOSH:
return do_mpc_arg1 (result_real, result_imag, mpc_acosh,
arg_real, arg_imag, format);
CASE_CFN_CATANH:
return do_mpc_arg1 (result_real, result_imag, mpc_atanh,
arg_real, arg_imag, format);
CASE_CFN_CEXP:
return do_mpc_arg1 (result_real, result_imag, mpc_exp,
arg_real, arg_imag, format);
default:
return false;
}
}
/* Subroutine of fold_const_call, with the same interface. Handle cases
where the arguments and result are numerical. */
static tree
fold_const_call_1 (combined_fn fn, tree type, tree arg)
{
machine_mode mode = TYPE_MODE (type);
machine_mode arg_mode = TYPE_MODE (TREE_TYPE (arg));
if (integer_cst_p (arg))
{
if (SCALAR_INT_MODE_P (mode))
{
wide_int result;
if (fold_const_call_ss (&result, fn, wi::to_wide (arg),
TYPE_PRECISION (type), TREE_TYPE (arg)))
return wide_int_to_tree (type, result);
}
return NULL_TREE;
}
if (real_cst_p (arg))
{
gcc_checking_assert (SCALAR_FLOAT_MODE_P (arg_mode));
if (mode == arg_mode)
{
/* real -> real. */
REAL_VALUE_TYPE result;
if (fold_const_call_ss (&result, fn, TREE_REAL_CST_PTR (arg),
REAL_MODE_FORMAT (mode)))
return build_real (type, result);
}
else if (COMPLEX_MODE_P (mode)
&& GET_MODE_INNER (mode) == arg_mode)
{
/* real -> complex real. */
REAL_VALUE_TYPE result_real, result_imag;
if (fold_const_call_cs (&result_real, &result_imag, fn,
TREE_REAL_CST_PTR (arg),
REAL_MODE_FORMAT (arg_mode)))
return build_complex (type,
build_real (TREE_TYPE (type), result_real),
build_real (TREE_TYPE (type), result_imag));
}
else if (INTEGRAL_TYPE_P (type))
{
/* real -> int. */
wide_int result;
if (fold_const_call_ss (&result, fn,
TREE_REAL_CST_PTR (arg),
TYPE_PRECISION (type),
REAL_MODE_FORMAT (arg_mode)))
return wide_int_to_tree (type, result);
}
return NULL_TREE;
}
if (complex_cst_p (arg))
{
gcc_checking_assert (COMPLEX_MODE_P (arg_mode));
machine_mode inner_mode = GET_MODE_INNER (arg_mode);
tree argr = TREE_REALPART (arg);
tree argi = TREE_IMAGPART (arg);
if (mode == arg_mode
&& real_cst_p (argr)
&& real_cst_p (argi))
{
/* complex real -> complex real. */
REAL_VALUE_TYPE result_real, result_imag;
if (fold_const_call_cc (&result_real, &result_imag, fn,
TREE_REAL_CST_PTR (argr),
TREE_REAL_CST_PTR (argi),
REAL_MODE_FORMAT (inner_mode)))
return build_complex (type,
build_real (TREE_TYPE (type), result_real),
build_real (TREE_TYPE (type), result_imag));
}
if (mode == inner_mode
&& real_cst_p (argr)
&& real_cst_p (argi))
{
/* complex real -> real. */
REAL_VALUE_TYPE result;
if (fold_const_call_sc (&result, fn,
TREE_REAL_CST_PTR (argr),
TREE_REAL_CST_PTR (argi),
REAL_MODE_FORMAT (inner_mode)))
return build_real (type, result);
}
return NULL_TREE;
}
return NULL_TREE;
}
/* Try to fold FN (ARG) to a constant. Return the constant on success,
otherwise return null. TYPE is the type of the return value. */
tree
fold_const_call (combined_fn fn, tree type, tree arg)
{
switch (fn)
{
case CFN_BUILT_IN_STRLEN:
if (const char *str = c_getstr (arg))
return build_int_cst (type, strlen (str));
return NULL_TREE;
CASE_CFN_NAN:
CASE_FLT_FN_FLOATN_NX (CFN_BUILT_IN_NAN):
case CFN_BUILT_IN_NAND32:
case CFN_BUILT_IN_NAND64:
case CFN_BUILT_IN_NAND128:
return fold_const_builtin_nan (type, arg, true);
CASE_CFN_NANS:
CASE_FLT_FN_FLOATN_NX (CFN_BUILT_IN_NANS):
return fold_const_builtin_nan (type, arg, false);
case CFN_REDUC_PLUS:
return fold_const_reduction (type, arg, PLUS_EXPR);
case CFN_REDUC_MAX:
return fold_const_reduction (type, arg, MAX_EXPR);
case CFN_REDUC_MIN:
return fold_const_reduction (type, arg, MIN_EXPR);
case CFN_REDUC_AND:
return fold_const_reduction (type, arg, BIT_AND_EXPR);
case CFN_REDUC_IOR:
return fold_const_reduction (type, arg, BIT_IOR_EXPR);
case CFN_REDUC_XOR:
return fold_const_reduction (type, arg, BIT_XOR_EXPR);
default:
return fold_const_call_1 (fn, type, arg);
}
}
/* Fold a call to IFN_FOLD_LEFT_<CODE> (ARG0, ARG1), returning a value
of type TYPE. */
static tree
fold_const_fold_left (tree type, tree arg0, tree arg1, tree_code code)
{
if (TREE_CODE (arg1) != VECTOR_CST)
return NULL_TREE;
unsigned HOST_WIDE_INT nelts;
if (!VECTOR_CST_NELTS (arg1).is_constant (&nelts))
return NULL_TREE;
for (unsigned HOST_WIDE_INT i = 0; i < nelts; i++)
{
arg0 = const_binop (code, type, arg0, VECTOR_CST_ELT (arg1, i));
if (arg0 == NULL_TREE || !CONSTANT_CLASS_P (arg0))
return NULL_TREE;
}
return arg0;
}
/* Try to evaluate:
*RESULT = FN (*ARG0, *ARG1)
in format FORMAT. Return true on success. */
static bool
fold_const_call_sss (real_value *result, combined_fn fn,
const real_value *arg0, const real_value *arg1,
const real_format *format)
{
switch (fn)
{
CASE_CFN_DREM:
CASE_CFN_REMAINDER:
return do_mpfr_arg2 (result, mpfr_remainder, arg0, arg1, format);
CASE_CFN_ATAN2:
return do_mpfr_arg2 (result, mpfr_atan2, arg0, arg1, format);
CASE_CFN_FDIM:
return do_mpfr_arg2 (result, mpfr_dim, arg0, arg1, format);
CASE_CFN_HYPOT:
return do_mpfr_arg2 (result, mpfr_hypot, arg0, arg1, format);
CASE_CFN_COPYSIGN:
CASE_CFN_COPYSIGN_FN:
*result = *arg0;
real_copysign (result, arg1);
return true;
CASE_CFN_FMIN:
CASE_CFN_FMIN_FN:
return do_mpfr_arg2 (result, mpfr_min, arg0, arg1, format);
CASE_CFN_FMAX:
CASE_CFN_FMAX_FN:
return do_mpfr_arg2 (result, mpfr_max, arg0, arg1, format);
CASE_CFN_POW:
return fold_const_pow (result, arg0, arg1, format);
default:
return false;
}
}
/* Try to evaluate:
*RESULT = FN (*ARG0, ARG1)
where FORMAT is the format of *RESULT and *ARG0. Return true on
success. */
static bool
fold_const_call_sss (real_value *result, combined_fn fn,
const real_value *arg0, const wide_int_ref &arg1,
const real_format *format)
{
switch (fn)
{
CASE_CFN_LDEXP:
return fold_const_builtin_load_exponent (result, arg0, arg1, format);
CASE_CFN_SCALBN:
CASE_CFN_SCALBLN:
return (format->b == 2
&& fold_const_builtin_load_exponent (result, arg0, arg1,
format));
CASE_CFN_POWI:
/* Avoid the folding if flag_signaling_nans is on and
operand is a signaling NaN. */
if (!flag_unsafe_math_optimizations
&& flag_signaling_nans
&& REAL_VALUE_ISSIGNALING_NAN (*arg0))
return false;
real_powi (result, format, arg0, arg1.to_shwi ());
return true;
default:
return false;
}
}
/* Try to evaluate:
*RESULT = FN (ARG0, *ARG1)
where FORMAT is the format of *RESULT and *ARG1. Return true on
success. */
static bool
fold_const_call_sss (real_value *result, combined_fn fn,
const wide_int_ref &arg0, const real_value *arg1,
const real_format *format)
{
switch (fn)
{
CASE_CFN_JN:
return do_mpfr_arg2 (result, mpfr_jn, arg0, arg1, format);
CASE_CFN_YN:
return (real_compare (GT_EXPR, arg1, &dconst0)
&& do_mpfr_arg2 (result, mpfr_yn, arg0, arg1, format));
default:
return false;
}
}
/* Try to evaluate:
RESULT = fn (ARG0, ARG1)
where FORMAT is the format of the real and imaginary parts of RESULT
(RESULT_REAL and RESULT_IMAG), of ARG0 (ARG0_REAL and ARG0_IMAG)
and of ARG1 (ARG1_REAL and ARG1_IMAG). Return true on success. */
static bool
fold_const_call_ccc (real_value *result_real, real_value *result_imag,
combined_fn fn, const real_value *arg0_real,
const real_value *arg0_imag, const real_value *arg1_real,
const real_value *arg1_imag, const real_format *format)
{
switch (fn)
{
CASE_CFN_CPOW:
return do_mpc_arg2 (result_real, result_imag, mpc_pow,
arg0_real, arg0_imag, arg1_real, arg1_imag, format);
default:
return false;
}
}
/* Subroutine of fold_const_call, with the same interface. Handle cases
where the arguments and result are numerical. */
static tree
fold_const_call_1 (combined_fn fn, tree type, tree arg0, tree arg1)
{
machine_mode mode = TYPE_MODE (type);
machine_mode arg0_mode = TYPE_MODE (TREE_TYPE (arg0));
machine_mode arg1_mode = TYPE_MODE (TREE_TYPE (arg1));
if (arg0_mode == arg1_mode
&& real_cst_p (arg0)
&& real_cst_p (arg1))
{
gcc_checking_assert (SCALAR_FLOAT_MODE_P (arg0_mode));
if (mode == arg0_mode)
{
/* real, real -> real. */
REAL_VALUE_TYPE result;
if (fold_const_call_sss (&result, fn, TREE_REAL_CST_PTR (arg0),
TREE_REAL_CST_PTR (arg1),
REAL_MODE_FORMAT (mode)))
return build_real (type, result);
}
return NULL_TREE;
}
if (real_cst_p (arg0)
&& integer_cst_p (arg1))
{
gcc_checking_assert (SCALAR_FLOAT_MODE_P (arg0_mode));
if (mode == arg0_mode)
{
/* real, int -> real. */
REAL_VALUE_TYPE result;
if (fold_const_call_sss (&result, fn, TREE_REAL_CST_PTR (arg0),
wi::to_wide (arg1),
REAL_MODE_FORMAT (mode)))
return build_real (type, result);
}
return NULL_TREE;
}
if (integer_cst_p (arg0)
&& real_cst_p (arg1))
{
gcc_checking_assert (SCALAR_FLOAT_MODE_P (arg1_mode));
if (mode == arg1_mode)
{
/* int, real -> real. */
REAL_VALUE_TYPE result;
if (fold_const_call_sss (&result, fn, wi::to_wide (arg0),
TREE_REAL_CST_PTR (arg1),
REAL_MODE_FORMAT (mode)))
return build_real (type, result);
}
return NULL_TREE;
}
if (arg0_mode == arg1_mode
&& complex_cst_p (arg0)
&& complex_cst_p (arg1))
{
gcc_checking_assert (COMPLEX_MODE_P (arg0_mode));
machine_mode inner_mode = GET_MODE_INNER (arg0_mode);
tree arg0r = TREE_REALPART (arg0);
tree arg0i = TREE_IMAGPART (arg0);
tree arg1r = TREE_REALPART (arg1);
tree arg1i = TREE_IMAGPART (arg1);
if (mode == arg0_mode
&& real_cst_p (arg0r)
&& real_cst_p (arg0i)
&& real_cst_p (arg1r)
&& real_cst_p (arg1i))
{
/* complex real, complex real -> complex real. */
REAL_VALUE_TYPE result_real, result_imag;
if (fold_const_call_ccc (&result_real, &result_imag, fn,
TREE_REAL_CST_PTR (arg0r),
TREE_REAL_CST_PTR (arg0i),
TREE_REAL_CST_PTR (arg1r),
TREE_REAL_CST_PTR (arg1i),
REAL_MODE_FORMAT (inner_mode)))
return build_complex (type,
build_real (TREE_TYPE (type), result_real),
build_real (TREE_TYPE (type), result_imag));
}
return NULL_TREE;
}
return NULL_TREE;
}
/* Try to fold FN (ARG0, ARG1) to a constant. Return the constant on success,
otherwise return null. TYPE is the type of the return value. */
tree
fold_const_call (combined_fn fn, tree type, tree arg0, tree arg1)
{
const char *p0, *p1;
char c;
switch (fn)
{
case CFN_BUILT_IN_STRSPN:
if ((p0 = c_getstr (arg0)) && (p1 = c_getstr (arg1)))
return build_int_cst (type, strspn (p0, p1));
return NULL_TREE;
case CFN_BUILT_IN_STRCSPN:
if ((p0 = c_getstr (arg0)) && (p1 = c_getstr (arg1)))
return build_int_cst (type, strcspn (p0, p1));
return NULL_TREE;
case CFN_BUILT_IN_STRCMP:
if ((p0 = c_getstr (arg0)) && (p1 = c_getstr (arg1)))
return build_cmp_result (type, strcmp (p0, p1));
return NULL_TREE;
case CFN_BUILT_IN_STRCASECMP:
if ((p0 = c_getstr (arg0)) && (p1 = c_getstr (arg1)))
{
int r = strcmp (p0, p1);
if (r == 0)
return build_cmp_result (type, r);
}
return NULL_TREE;
case CFN_BUILT_IN_INDEX:
case CFN_BUILT_IN_STRCHR:
if ((p0 = c_getstr (arg0)) && target_char_cst_p (arg1, &c))
{
const char *r = strchr (p0, c);
if (r == NULL)
return build_int_cst (type, 0);
return fold_convert (type,
fold_build_pointer_plus_hwi (arg0, r - p0));
}
return NULL_TREE;
case CFN_BUILT_IN_RINDEX:
case CFN_BUILT_IN_STRRCHR:
if ((p0 = c_getstr (arg0)) && target_char_cst_p (arg1, &c))
{
const char *r = strrchr (p0, c);
if (r == NULL)
return build_int_cst (type, 0);
return fold_convert (type,
fold_build_pointer_plus_hwi (arg0, r - p0));
}
return NULL_TREE;
case CFN_BUILT_IN_STRSTR:
if ((p1 = c_getstr (arg1)))
{
if ((p0 = c_getstr (arg0)))
{
const char *r = strstr (p0, p1);
if (r == NULL)
return build_int_cst (type, 0);
return fold_convert (type,
fold_build_pointer_plus_hwi (arg0, r - p0));
}
if (*p1 == '\0')
return fold_convert (type, arg0);
}
return NULL_TREE;
case CFN_FOLD_LEFT_PLUS:
return fold_const_fold_left (type, arg0, arg1, PLUS_EXPR);
default:
return fold_const_call_1 (fn, type, arg0, arg1);
}
}
/* Try to evaluate:
*RESULT = FN (*ARG0, *ARG1, *ARG2)
in format FORMAT. Return true on success. */
static bool
fold_const_call_ssss (real_value *result, combined_fn fn,
const real_value *arg0, const real_value *arg1,
const real_value *arg2, const real_format *format)
{
switch (fn)
{
CASE_CFN_FMA:
CASE_CFN_FMA_FN:
return do_mpfr_arg3 (result, mpfr_fma, arg0, arg1, arg2, format);
default:
return false;
}
}
/* Subroutine of fold_const_call, with the same interface. Handle cases
where the arguments and result are numerical. */
static tree
fold_const_call_1 (combined_fn fn, tree type, tree arg0, tree arg1, tree arg2)
{
machine_mode mode = TYPE_MODE (type);
machine_mode arg0_mode = TYPE_MODE (TREE_TYPE (arg0));
machine_mode arg1_mode = TYPE_MODE (TREE_TYPE (arg1));
machine_mode arg2_mode = TYPE_MODE (TREE_TYPE (arg2));
if (arg0_mode == arg1_mode
&& arg0_mode == arg2_mode
&& real_cst_p (arg0)
&& real_cst_p (arg1)
&& real_cst_p (arg2))
{
gcc_checking_assert (SCALAR_FLOAT_MODE_P (arg0_mode));
if (mode == arg0_mode)
{
/* real, real, real -> real. */
REAL_VALUE_TYPE result;
if (fold_const_call_ssss (&result, fn, TREE_REAL_CST_PTR (arg0),
TREE_REAL_CST_PTR (arg1),
TREE_REAL_CST_PTR (arg2),
REAL_MODE_FORMAT (mode)))
return build_real (type, result);
}
return NULL_TREE;
}
return NULL_TREE;
}
/* Try to fold FN (ARG0, ARG1, ARG2) to a constant. Return the constant on
success, otherwise return null. TYPE is the type of the return value. */
tree
fold_const_call (combined_fn fn, tree type, tree arg0, tree arg1, tree arg2)
{
const char *p0, *p1;
char c;
unsigned HOST_WIDE_INT s0, s1;
size_t s2 = 0;
switch (fn)
{
case CFN_BUILT_IN_STRNCMP:
if (!host_size_t_cst_p (arg2, &s2))
return NULL_TREE;
if (s2 == 0
&& !TREE_SIDE_EFFECTS (arg0)
&& !TREE_SIDE_EFFECTS (arg1))
return build_int_cst (type, 0);
else if ((p0 = c_getstr (arg0)) && (p1 = c_getstr (arg1)))
return build_int_cst (type, strncmp (p0, p1, s2));
return NULL_TREE;
case CFN_BUILT_IN_STRNCASECMP:
if (!host_size_t_cst_p (arg2, &s2))
return NULL_TREE;
if (s2 == 0
&& !TREE_SIDE_EFFECTS (arg0)
&& !TREE_SIDE_EFFECTS (arg1))
return build_int_cst (type, 0);
else if ((p0 = c_getstr (arg0))
&& (p1 = c_getstr (arg1))
&& strncmp (p0, p1, s2) == 0)
return build_int_cst (type, 0);
return NULL_TREE;
case CFN_BUILT_IN_BCMP:
case CFN_BUILT_IN_MEMCMP:
if (!host_size_t_cst_p (arg2, &s2))
return NULL_TREE;
if (s2 == 0
&& !TREE_SIDE_EFFECTS (arg0)
&& !TREE_SIDE_EFFECTS (arg1))
return build_int_cst (type, 0);
if ((p0 = c_getstr (arg0, &s0))
&& (p1 = c_getstr (arg1, &s1))
&& s2 <= s0
&& s2 <= s1)
return build_cmp_result (type, memcmp (p0, p1, s2));
return NULL_TREE;
case CFN_BUILT_IN_MEMCHR:
if (!host_size_t_cst_p (arg2, &s2))
return NULL_TREE;
if (s2 == 0
&& !TREE_SIDE_EFFECTS (arg0)
&& !TREE_SIDE_EFFECTS (arg1))
return build_int_cst (type, 0);
if ((p0 = c_getstr (arg0, &s0))
&& s2 <= s0
&& target_char_cst_p (arg1, &c))
{
const char *r = (const char *) memchr (p0, c, s2);
if (r == NULL)
return build_int_cst (type, 0);
return fold_convert (type,
fold_build_pointer_plus_hwi (arg0, r - p0));
}
return NULL_TREE;
default:
return fold_const_call_1 (fn, type, arg0, arg1, arg2);
}
}
/* Fold a fma operation with arguments ARG[012]. */
tree
fold_fma (location_t, tree type, tree arg0, tree arg1, tree arg2)
{
REAL_VALUE_TYPE result;
if (real_cst_p (arg0)
&& real_cst_p (arg1)
&& real_cst_p (arg2)
&& do_mpfr_arg3 (&result, mpfr_fma, TREE_REAL_CST_PTR (arg0),
TREE_REAL_CST_PTR (arg1), TREE_REAL_CST_PTR (arg2),
REAL_MODE_FORMAT (TYPE_MODE (type))))
return build_real (type, result);
return NULL_TREE;
}