__PS_RESS

Syntax

#include <ppc_ps.h>

f32x2 __PS_RESS(float f1);

Parameters

f1 Paired single value.

Return Values

__PS_RESS returns an estimate of the reciprocal of the input, duplicated into both parts of the paired single.

Description

Returns the estimated reciprocal, correct to one part in 4096.

Behavior of __PS_RES

Compute a quick estimate of the reciprocal of the input values. The estimates are correct to a precision of one part in 4096 of the reciprocal. That is, for each value x and estimate, the following equation is true:

| (estimate − (1/x)) / (1/x) | ≤ 1/4096

#include <ppc_ghs.h>

float in;
f32x2 out;
...
out = __PS_RESS(in);

Is equivalent to:

out[0] = fres(in[0]);
out[1] = out[0];

Do Not Call From

None.

See Also

Paired Single Type

Paired Single Functions

__PS_ABS
__PS_ADD
__PS_ADDS
__PS_FDUP
__PS_DIV
__PS_DIVS
__PS_MADD
__PS_MADDS
__PS_MADDS0
__PS_MADDS1
__PS_MERGE00
__PS_MERGE01
__PS_MERGE10
__PS_MERGE11
__PS_MSUB
__PS_MSUBS
__PS_MUL
__PS_MULS
__PS_MULS0
__PS_MULS1
__PS_NABS
__PS_NMADD
__PS_NMADDS
__PS_NMSUB
__PS_NMSUBS
__PS_NEG
__PS_NEGS
__PS_RES
__PS_RSQRTE
__PS_SEL
__PS_SUB
__PS_SUM0
__PS_SUM1
__PS_SUBS
__PSQ_L
__PSQ_LX
__PSQ_ST
__PSQ_STX

Fast Cast Routines

OSInitFastCast
OSf32tos16
OSf32tos8
OSf32tou16
OSf32tou8
OSs16tof32
OSs8tof32
OSu16tof32
OSu8tof32

Revision History

2013/05/08 Automated cleanup pass.
2011/09/21 Initial version.


CONFIDENTIAL