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Merge pull request #17 from ricovangenugten/master

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Fixed issue simonyiszk/csdr#15
This commit is contained in:
András Retzler 2017-03-05 10:32:58 +01:00 committed by GitHub
commit c3e5d3f433
2 changed files with 4 additions and 8 deletions
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2
csdr.c
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@ -1059,7 +1059,7 @@ int main(int argc, char *argv[])
padded_taps_length = taps_length+(NEON_ALIGNMENT/4)-1 - ((taps_length+(NEON_ALIGNMENT/4)-1)%(NEON_ALIGNMENT/4));
fprintf(stderr,"padded_taps_length = %d\n", padded_taps_length);
taps = (float*) (float*)malloc(padded_taps_length+NEON_ALIGNMENT);
taps = (float*) (float*)malloc((padded_taps_length+NEON_ALIGNMENT)*sizeof(float));
fprintf(stderr,"taps = %x\n", taps);
taps = (float*)((((unsigned)taps)+NEON_ALIGNMENT-1) & ~(NEON_ALIGNMENT-1));
fprintf(stderr,"taps = %x\n", taps);

10
libcsdr.c
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@ -480,11 +480,7 @@ int fir_decimate_cc(complexf *input, complexf *output, int input_size, int decim
for(int i=0; i<input_size; i+=decimation) //@fir_decimate_cc: outer loop
{
if(i+taps_length>input_size) break;
register float acci=0;
register float accq=0;
register int ti=0;
register float* pinput=(float*)&(input[i+ti]);
register float* pinput=(float*)&(input[i]);
register float* ptaps=taps;
register float* ptaps_end=taps+taps_length;
float quad_acciq [8];
@ -497,8 +493,8 @@ q4, q5: accumulator for I branch and Q branch (will be the output)
*/
asm volatile(
" vmov.f32 q4, #0.0\n\t" //another way to null the accumulators
" vmov.f32 q5, #0.0\n\t"
" veor q4, q4\n\t"
" veor q5, q5\n\t"
"for_fdccasm: vld2.32 {q0-q1}, [%[pinput]]!\n\t" //load q0 and q1 directly from the memory address stored in pinput, with interleaving (so that we get the I samples in q0 and the Q samples in q1), also increment the memory address in pinput (hence the "!" mark) //http://community.arm.com/groups/processors/blog/2010/03/17/coding-for-neon--part-1-load-and-stores
" vld1.32 {q2}, [%[ptaps]]!\n\t"
" vmla.f32 q4, q0, q2\n\t" //quad_acc_i += quad_input_i * quad_taps_1 //http://stackoverflow.com/questions/3240440/how-to-use-the-multiply-and-accumulate-intrinsics-in-arm-cortex-a8 //http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0489e/CIHEJBIE.html