ArmSoftFloatLib.c

/*
 * Copyright (c) 2015 - 2019, Linaro Limited
 *
 * SPDX-License-Identifier: BSD-2-Clause-Patent
 */
 
#include "platform.h"
#include <softfloat.h>
 
/*
 * On ARM32 EABI defines both a soft-float ABI and a hard-float ABI,
 * hard-float is basically a super set of soft-float. Hard-float requires
 * all the support routines provided for soft-float, but the compiler may
 * choose to optimize to not use some of them.
 *
 * The AEABI functions uses soft-float calling convention even if the
 * functions are compiled for hard-float. So where float and double would
 * have been expected we use aeabi_float_t and aeabi_double_t respectively
 * instead.
 */
typedef uint32_t  aeabi_float_t;
typedef uint64_t  aeabi_double_t;
 
/*
 * Helpers to convert between float32 and aeabi_float_t, and float64 and
 * aeabi_double_t used by the AEABI functions below.
 */
static aeabi_float_t
f32_to_f (
  float32_t  val
  )
{
  return val.v;
}
 
static float32_t
f32_from_f (
  aeabi_float_t  val
  )
{
  float32_t  res;
 
  res.v = val;
 
  return res;
}
 
static aeabi_double_t
f64_to_d (
  float64_t  val
  )
{
  return val.v;
}
 
static float64_t
f64_from_d (
  aeabi_double_t  val
  )
{
  float64_t  res;
 
  res.v = val;
 
  return res;
}
 
/*
 * From ARM Run-time ABI for ARM Architecture
 * ARM IHI 0043D, current through ABI release 2.09
 *
 * 4.1.2 The floating-point helper functions
 */
 
/*
 * Table 2, Standard aeabi_double_t precision floating-point arithmetic helper
 * functions
 */
aeabi_double_t
__aeabi_dadd (
  aeabi_double_t  a,
  aeabi_double_t  b
  )
{
  return f64_to_d (f64_add (f64_from_d (a), f64_from_d (b)));
}
 
aeabi_double_t
__aeabi_ddiv (
  aeabi_double_t  a,
  aeabi_double_t  b
  )
{
  return f64_to_d (f64_div (f64_from_d (a), f64_from_d (b)));
}
 
aeabi_double_t
__aeabi_dmul (
  aeabi_double_t  a,
  aeabi_double_t  b
  )
{
  return f64_to_d (f64_mul (f64_from_d (a), f64_from_d (b)));
}
 
aeabi_double_t
__aeabi_drsub (
  aeabi_double_t  a,
  aeabi_double_t  b
  )
{
  return f64_to_d (f64_sub (f64_from_d (b), f64_from_d (a)));
}
 
aeabi_double_t
__aeabi_dsub (
  aeabi_double_t  a,
  aeabi_double_t  b
  )
{
  return f64_to_d (f64_sub (f64_from_d (a), f64_from_d (b)));
}
 
/*
 * Table 3, double precision floating-point comparison helper functions
 */
int
__aeabi_dcmpeq (
  aeabi_double_t  a,
  aeabi_double_t  b
  )
{
  return f64_eq (f64_from_d (a), f64_from_d (b));
}
 
int
__aeabi_dcmplt (
  aeabi_double_t  a,
  aeabi_double_t  b
  )
{
  return f64_lt (f64_from_d (a), f64_from_d (b));
}
 
int
__aeabi_dcmple (
  aeabi_double_t  a,
  aeabi_double_t  b
  )
{
  return f64_le (f64_from_d (a), f64_from_d (b));
}
 
int
__aeabi_dcmpge (
  aeabi_double_t  a,
  aeabi_double_t  b
  )
{
  return f64_le (f64_from_d (b), f64_from_d (a));
}
 
int
__aeabi_dcmpgt (
  aeabi_double_t  a,
  aeabi_double_t  b
  )
{
  return f64_lt (f64_from_d (b), f64_from_d (a));
}
 
/*
 * Table 4, Standard single precision floating-point arithmetic helper
 * functions
 */
aeabi_float_t
__aeabi_fadd (
  aeabi_float_t  a,
  aeabi_float_t  b
  )
{
  return f32_to_f (f32_add (f32_from_f (a), f32_from_f (b)));
}
 
aeabi_float_t
__aeabi_fdiv (
  aeabi_float_t  a,
  aeabi_float_t  b
  )
{
  return f32_to_f (f32_div (f32_from_f (a), f32_from_f (b)));
}
 
aeabi_float_t
__aeabi_fmul (
  aeabi_float_t  a,
  aeabi_float_t  b
  )
{
  return f32_to_f (f32_mul (f32_from_f (a), f32_from_f (b)));
}
 
aeabi_float_t
__aeabi_frsub (
  aeabi_float_t  a,
  aeabi_float_t  b
  )
{
  return f32_to_f (f32_sub (f32_from_f (b), f32_from_f (a)));
}
 
aeabi_float_t
__aeabi_fsub (
  aeabi_float_t  a,
  aeabi_float_t  b
  )
{
  return f32_to_f (f32_sub (f32_from_f (a), f32_from_f (b)));
}
 
/*
 * Table 5, Standard single precision floating-point comparison helper
 * functions
 */
int
__aeabi_fcmpeq (
  aeabi_float_t  a,
  aeabi_float_t  b
  )
{
  return f32_eq (f32_from_f (a), f32_from_f (b));
}
 
int
__aeabi_fcmplt (
  aeabi_float_t  a,
  aeabi_float_t  b
  )
{
  return f32_lt (f32_from_f (a), f32_from_f (b));
}
 
int
__aeabi_fcmple (
  aeabi_float_t  a,
  aeabi_float_t  b
  )
{
  return f32_le (f32_from_f (a), f32_from_f (b));
}
 
int
__aeabi_fcmpge (
  aeabi_float_t  a,
  aeabi_float_t  b
  )
{
  return f32_le (f32_from_f (b), f32_from_f (a));
}
 
int
__aeabi_fcmpgt (
  aeabi_float_t  a,
  aeabi_float_t  b
  )
{
  return f32_lt (f32_from_f (b), f32_from_f (a));
}
 
/*
 * Table 6, Standard floating-point to integer conversions
 */
int
__aeabi_d2iz (
  aeabi_double_t  a
  )
{
  return f64_to_i32_r_minMag (f64_from_d (a), false);
}
 
unsigned
__aeabi_d2uiz (
  aeabi_double_t  a
  )
{
  return f64_to_ui32_r_minMag (f64_from_d (a), false);
}
 
long long
__aeabi_d2lz (
  aeabi_double_t  a
  )
{
  return f64_to_i64_r_minMag (f64_from_d (a), false);
}
 
unsigned long long
__aeabi_d2ulz (
  aeabi_double_t  a
  )
{
  return f64_to_ui64_r_minMag (f64_from_d (a), false);
}
 
int
__aeabi_f2iz (
  aeabi_float_t  a
  )
{
  return f32_to_i32_r_minMag (f32_from_f (a), false);
}
 
unsigned
__aeabi_f2uiz (
  aeabi_float_t  a
  )
{
  return f32_to_ui32_r_minMag (f32_from_f (a), false);
}
 
long long
__aeabi_f2lz (
  aeabi_float_t  a
  )
{
  return f32_to_i64_r_minMag (f32_from_f (a), false);
}
 
unsigned long long
__aeabi_f2ulz (
  aeabi_float_t  a
  )
{
  return f32_to_ui64_r_minMag (f32_from_f (a), false);
}
 
/*
 * Table 7, Standard conversions between floating types
 */
aeabi_float_t
__aeabi_d2f (
  aeabi_double_t  a
  )
{
  return f32_to_f (f64_to_f32 (f64_from_d (a)));
}
 
aeabi_double_t
__aeabi_f2d (
  aeabi_float_t  a
  )
{
  return f64_to_d (f32_to_f64 (f32_from_f (a)));
}
 
/*
 * Table 8, Standard integer to floating-point conversions
 */
aeabi_double_t
__aeabi_i2d (
  int  a
  )
{
  return f64_to_d (i32_to_f64 (a));
}
 
aeabi_double_t
__aeabi_ui2d (
  unsigned  a
  )
{
  return f64_to_d (ui32_to_f64 (a));
}
 
aeabi_double_t
__aeabi_l2d (
  long long  a
  )
{
  return f64_to_d (i64_to_f64 (a));
}
 
aeabi_double_t
__aeabi_ul2d (
  unsigned long long  a
  )
{
  return f64_to_d (ui64_to_f64 (a));
}
 
aeabi_float_t
__aeabi_i2f (
  int  a
  )
{
  return f32_to_f (i32_to_f32 (a));
}
 
aeabi_float_t
__aeabi_ui2f (
  unsigned  a
  )
{
  return f32_to_f (ui32_to_f32 (a));
}
 
aeabi_float_t
__aeabi_l2f (
  long long  a
  )
{
  return f32_to_f (i64_to_f32 (a));
}
 
aeabi_float_t
__aeabi_ul2f (
  unsigned long long  a
  )
{
  return f32_to_f (ui64_to_f32 (a));
}