math.c File Reference

#include "math.h"
#include <platform.h>

Data Structures
union	FloatU32

Macros
#define	EXP_MASK   0x7F800000
#define	EXP_ZERO   0x3F800000
#define	MANT_MASK   0x007FFFFF
#define	SIGN_BIT   0x80000000
#define	F32_BIT_CAST(raw_x)   (*(float*) &raw_x)
#define	F32_UNBIASED_EXPONENT(raw_x)    (((raw_x & 0xFF800000) >> 23) - /*exponent bias*/ 127)
#define	F32_HIGH_MANTISSA_BITS(raw_x)    ((raw_x >> 16) & 0x7F)
#define	F32_LOW_MANTISSA_BITS(raw_x)    (raw_x & 0xFFFF)
#define	LN2   0.6931472f

Functions
float	logf (float x)

Variables
float	float_nan = 0.0 / 0.0
float	float_inf = 1.0e100 * 1.0e100
const float	__ln_F []
	Math lookup tables - defined in math_data.c Keeping them in a separate compilation unit prevents the compiler from hoisting array base addresses, which is needed to match the original code.
const float	__one_over_F []
	__one_over_F[n] = 1.0 / (1.0 + n/128) for n = 0..128
const float	__sincos_on_quadrant []
const float	__sincos_poly []
const u32	__logf_C0_bits
	logf Taylor series coefficients - stored as u32 bit patterns in math_data.c to get the right codegen (lwz load from global)
const u32	__logf_C1_bits

Macro Definition Documentation

EXP_MASK

#define EXP_MASK   0x7F800000

EXP_ZERO

#define EXP_ZERO   0x3F800000

MANT_MASK

#define MANT_MASK   0x007FFFFF

SIGN_BIT

#define SIGN_BIT   0x80000000

F32_BIT_CAST

#define F32_BIT_CAST

(

raw_x

)

(*(float*) &raw_x)

F32_UNBIASED_EXPONENT

#define F32_UNBIASED_EXPONENT

(

raw_x

)

(((raw_x & 0xFF800000) >> 23) - /*exponent bias*/ 127)

F32_HIGH_MANTISSA_BITS

#define F32_HIGH_MANTISSA_BITS

(

raw_x

)

((raw_x >> 16) & 0x7F)

F32_LOW_MANTISSA_BITS

#define F32_LOW_MANTISSA_BITS

(

raw_x

)

(raw_x & 0xFFFF)

LN2

#define LN2   0.6931472f

Function Documentation

logf()

float logf

(

float

x

)

Variable Documentation

float_nan

float float_nan = 0.0 / 0.0

Todo:

use standard library constants, because this definition seems to be platform dependant

float_inf

float float_inf = 1.0e100 * 1.0e100

__ln_F

const float __ln_F[]

extern

Math lookup tables - defined in math_data.c Keeping them in a separate compilation unit prevents the compiler from hoisting array base addresses, which is needed to match the original code.

Math lookup tables - defined in math_data.c Keeping them in a separate compilation unit prevents the compiler from hoisting array base addresses, which is needed to match the original code.

These arrays are kept in a separate compilation unit so that functions like logf() generate separate address loads for each table access, rather than hoisting a shared base pointer. __ln_F[n] = ln(1.0 + n/128) for n = 0 .. 128

__one_over_F

const float __one_over_F[]

extern

__one_over_F[n] = 1.0 / (1.0 + n/128) for n = 0..128

__sincos_on_quadrant

const float __sincos_on_quadrant[]

extern

__sincos_poly

const float __sincos_poly[]

extern

__logf_C0_bits

const u32 __logf_C0_bits

extern

logf Taylor series coefficients - stored as u32 bit patterns in math_data.c to get the right codegen (lwz load from global)

logf Taylor series coefficients - stored as u32 bit patterns in math_data.c to get the right codegen (lwz load from global)

__logf_C1_bits

const u32 __logf_C1_bits

extern