Problem with adopting ccomplex_dotprod_sse() in my block

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1

Hi, everyone,

Recently, I’m implementing some synchronization algorithm in block,
which
require higher efficiency. I try to use the function
ccomplex_dotprod_sse()
to speed up the block, but I always get “segment fault”.
I’m using a PC with Pentium D CPU, and I’m sure the
ccomplex_dotprod_sse()
works well in the fir filter blocks.
I just simply include the ccomplex_dotprod_x86.h and call the
ccmplex_dotprod_sse() function. Maybe I missed something but I have no
idea
of what it is? Please give me some hints.

2

On Wed, Mar 14, 2007 at 05:26:02PM +0800, hanwen wrote:

Hi, everyone,

Recently, I’m implementing some synchronization algorithm in block, which
require higher efficiency. I try to use the function ccomplex_dotprod_sse()
to speed up the block, but I always get “segment fault”.
I’m using a PC with Pentium D CPU, and I’m sure the ccomplex_dotprod_sse()
works well in the fir filter blocks.
I just simply include the ccomplex_dotprod_x86.h and call the
ccmplex_dotprod_sse() function. Maybe I missed something but I have no idea
of what it is? Please give me some hints.

You’re probably not honoring its alignment requirements.

input and taps are guarenteed to be 16 byte aligned.

n_2_ccomplex_blocks is != 0

ccomplex_dotprod_generic (const float *input,

const float *taps, unsigned

n_2_ccomplex_blocks, float *result)

{

float sum0 = 0;

float sum1 = 0;

float sum2 = 0;

float sum3 = 0;

do {

sum0 += input[0] * taps[0] - input[1] * taps[1];

sum1 += input[0] * taps[1] + input[1] * taps[0];

sum2 += input[2] * taps[2] - input[3] * taps[3];

sum3 += input[2] * taps[3] + input[3] * taps[2];

input += 4;

taps += 4;

} while (–n_2_ccomplex_blocks != 0);

result[0] = sum0 + sum2;

result[1] = sum1 + sum3;

}

There’s a reason for all that other code that you are ignoring…

Eric