Remove redundant copy of large array in JT9 decoder

Also moved  the same large array  from stack to heap  which along with
other prior  changes now allows  the Windows jt9 OpenMP  executable to
run with a default stack size again.

This also removes a crash on the Mac version which was probably due to
excessive stack usage.

Net result is an even faster JT9 decoder.

git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@4942 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
This commit is contained in:
Bill Somerville 2015-02-08 09:53:20 +00:00
parent c86f37cade
commit 127f72f3ad
2 changed files with 86 additions and 96 deletions

View File

@ -743,9 +743,6 @@ qt5_use_modules (jt9 Core)
if (${OPENMP_FOUND}) if (${OPENMP_FOUND})
add_executable (jt9_omp lib/jt9.f90 lib/jt9a.f90 lib/jt9b.f90 lib/jt9c.f90 ${jt9_CXXSRCS} wsjtx.rc) add_executable (jt9_omp lib/jt9.f90 lib/jt9a.f90 lib/jt9b.f90 lib/jt9c.f90 ${jt9_CXXSRCS} wsjtx.rc)
if (WIN32)
set (_extra_omp_link_flags "-Wl,--stack,8388608")
endif (WIN32)
set_target_properties (jt9_omp set_target_properties (jt9_omp
PROPERTIES PROPERTIES
COMPILE_FLAGS "${OpenMP_C_FLAGS}" COMPILE_FLAGS "${OpenMP_C_FLAGS}"

View File

@ -10,27 +10,19 @@ subroutine downsam9(id2,npts8,nsps8,newdat,nspsd,fpk,c2,nz2)
parameter (NMAX1=604800) parameter (NMAX1=604800)
type(C_PTR) :: plan !Pointers plan for big FFT type(C_PTR) :: plan !Pointers plan for big FFT
integer*2 id2(0:8*npts8-1) integer*2 id2(0:8*npts8-1)
real*4 x1(0:NMAX1-1) real*4, pointer :: x1(:)
complex c1(0:NMAX1/2) complex c1(0:NMAX1/2)
complex c2(0:1440-1) complex c2(0:1440-1)
real s(5000) real s(5000)
logical first logical first
common/patience/npatience,nthreads common/patience/npatience,nthreads
data first/.true./ data first/.true./
save plan,first,c1,s save plan,first,c1,s,x1
nfft1=NMAX1 !Forward FFT length nfft1=NMAX1 !Forward FFT length
df1=12000.0/nfft1 df1=12000.0/nfft1
npts=8*npts8 npts=8*npts8
if(newdat.eq.1) then
fac=6.963e-6 !Why this weird constant?
do i=0,npts-1
x1(i)=fac*id2(i)
enddo
x1(npts:nfft1-1)=0. !Zero the rest of x1
endif
if(first) then if(first) then
nflags=FFTW_ESTIMATE nflags=FFTW_ESTIMATE
if(npatience.eq.1) nflags=FFTW_ESTIMATE_PATIENT if(npatience.eq.1) nflags=FFTW_ESTIMATE_PATIENT
@ -40,6 +32,9 @@ subroutine downsam9(id2,npts8,nsps8,newdat,nspsd,fpk,c2,nz2)
! Plan the FFTs just once ! Plan the FFTs just once
!$omp critical(fftw) ! serialize non thread-safe FFTW3 calls !$omp critical(fftw) ! serialize non thread-safe FFTW3 calls
plan=fftwf_alloc_real(NMAX1)
call c_f_pointer(plan,x1,[NMAX1])
x1(0:NMAX1-1) => x1 !remap bounds
call fftwf_plan_with_nthreads(nthreads) call fftwf_plan_with_nthreads(nthreads)
plan=fftwf_plan_dft_r2c_1d(nfft1,x1,c1,nflags) plan=fftwf_plan_dft_r2c_1d(nfft1,x1,c1,nflags)
call fftwf_plan_with_nthreads(1) call fftwf_plan_with_nthreads(1)
@ -50,9 +45,7 @@ subroutine downsam9(id2,npts8,nsps8,newdat,nspsd,fpk,c2,nz2)
if(newdat.eq.1) then if(newdat.eq.1) then
fac=6.963e-6 !Why this weird constant? fac=6.963e-6 !Why this weird constant?
do i=0,npts-1 x1(0:npts-1)=fac*id2(0:npts-1)
x1(i)=fac*id2(i)
enddo
x1(npts:nfft1-1)=0. !Zero the rest of x1 x1(npts:nfft1-1)=0. !Zero the rest of x1
call timer('FFTbig9 ',0) call timer('FFTbig9 ',0)
call fftwf_execute_dft_r2c(plan,x1,c1) call fftwf_execute_dft_r2c(plan,x1,c1)