Floating-point Library for Integer Processors

Software support for floating-point arithmetic on integer processors.


FLIP is a C library that provides a software support for binary32 floating-point arithmetic on integer processors. This library is particularly targeted to VLIW or DSP processors (that is, embedded systems), and has been validated on VLIW integer processors like those of the ST200 family from STMicroelectronics.

This library provides software implementation for the five basic arithmetic operations (addition, subtraction, multiplication, division, and square root) with subnormal numbers support, and for the four rounding-direction attributes (RoundTiesToEven, RoundTowardPositive, RoundTowardNegative, RoundTowardZero) required by the IEEE 754-2008 standard.

FLIP is contributed by the Arénaire team (INRIA Grenoble - Rhône-Alpes) within the LIP laboratory at ENS Lyon.

The main developers of the latest version (FLIP-1.0) are Claude-Pierre Jeannerod and Guillaume Revy.


FLIP has been validated on ST231 VLIW processor. Performances on ST231 can be found here.



The following program can be downloaded here.

  float a = 17.0128421783447265625000000f;
  float b = 1.24564564228057861328125000f;

  printf("a = %1.30f\n",a);
  printf("b = %1.30f\n",b);

  printf("add(a,b)        = %1.30f\n",flip_addf(a,b));
  printf("sub(a,b)        = %1.30f\n",flip_subf(a,b));
  printf("mul(a,b)        = %1.30f\n",flip_mulf(a,b));
  printf("div(a,b)        = %1.30f\n",flip_divf(a,b));

  printf("sqrt(a)         = %1.30f\n",flip_sqrtf(a));
  printf("sqrt(b)         = %1.30f\n",flip_sqrtf(b));

  return 0;
To compile, just type in a terminal:
$ gcc -o test-flip test-flip.c -lflip
The result of this program is:
$ ./test-flip
a = 17.012842178344726562500000000000
b = 1.245645642280578613281250000000
add(a,b)        = 18.258487701416015625000000000000
sub(a,b)        = 15.767196655273437500000000000000
mul(a,b)        = 21.191972732543945312500000000000
div(a,b)        = 13.657850265502929687500000000000
sqrt(a)         = 4.124662876129150390625000000000
sqrt(b)         = 1.116084933280944824218750000000


Claude-Pierre Jeannerod, Guillaume Revy
Last updated: Mon 19 Mar 2012 12:25:55 CET.