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Libraries and Floating Point Support Guide

Preface The ARM C and C++ Libraries The ARM C Micro-library Floating-point Support About floating-point support The software floating-point library, fplib Calling fplib routines fplib arithmetic on numbers in a particular format fplib conversions between floats, long longs, doub fplib comparisons between floats and doubles fplib C99 functions Controlling the ARM floating-point environment Floating-point functions for compatibility with Mi C99-compatible functions for controlling the ARM f C99 rounding mode and floating-point exception mac Exception flag handling Functions for handling rounding modes Functions for saving and restoring the whole float Functions for temporarily disabling exceptions ARM floating-point compiler extensions to the C99 Writing a custom exception trap handler Example of a custom exception handler Exception trap handling by signals mathlib double and single-precision floating-point IEEE 754 arithmetic Basic data types for IEEE 754 arithmetic Single precision data type for IEEE 754 arithmetic Double precision data type for IEEE 754 arithmetic Sample single precision floating-point values for Sample double precision floating-point values for IEEE 754 arithmetic and rounding Exceptions arising from IEEE 754 floating-point ar Exception types recognized by the ARM floating-poi Using the Vector Floating-Point (VFP) support libr The C and C++ Library Functions reference Floating-point Support Functions Reference

fplib C99 functions

3.2.5 fplib C99 functions

fplib provides a number of routines that implement C99 functionality.

The following table describes these functions.

Table 3-4 fplib C99 functions

Function Argument types Return type Returns section Standard
ilogb double int Exponent of argument x 7.12.6.5
ilogbf float int Exponent of argument x 7.12.6.5
ilogbl long double int Exponent of argument x 7.12.6.5
logb double double Exponent of argument x 7.12.6.11
logbf float float Exponent of argument x 7.12.6.11
logbl long double long double Exponent of argument x 7.12.6.11
scalbn double, int double x * (FLT_RADIX ** n) 7.12.6.13
scalbnf float, int float x * (FLT_RADIX ** n) 7.12.6.13
scalbnl long double, int long double x * (FLT_RADIX ** n) 7.12.6.13
scalbln double, long int double x * (FLT_RADIX ** n) 7.12.6.13
scalblnf float, long int float x * (FLT_RADIX ** n) 7.12.6.13
scalblnl long double, long int long double x * (FLT_RADIX ** n) 7.12.6.13
nextafter 2 double double Next representable value after x towards y 7.12.11.3
nextafterf 2 float float Next representable value after x towards y 7.12.11.3
nextafterl 2 long double long double Next representable value after x towards y 7.12.11.3
nexttoward double, long double double Next representable value after x towards y 7.12.11.4
nexttowardf float, long double float Next representable value after x towards y 7.12.11.4
nexttowardl 2 long double long double Next representable value after x towards y 7.12.11.4
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