Speech Coder Filters Using the StarCore SC140/SC1400 Cores

1 Speech Coder Basics ...............................................2 1.1 GSM EFR ................................................................2 1.2 G.729 .......................................................................2 1.3 The Residu() Function ............................................ 2 1.4 The Convolve() Function ........................................3 1.5 The Syn_filt() Function ...........................................3 2 StarCore SC140/SC1400 Compiler ........................4 2.1 StarCore Compiler ..................................................4 3 Optimization Phases and Methods ..........................5 3.1 C Optimizations ......................................................5 3.2 Assembly .................................................................7 4 Optimization of the Residu() Function ...................7 4.1 Assembly................................................................. 9 4.2 Results ...................................................................10 5 Optimization of the Convolve() Function .............10 5.1 Assembly ...............................................................13 5.2 Results ...................................................................15 6 Optimization of the Syn_filt() Function ................15 6.1 Optimized C ..........................................................16 6.2 Assembly ...............................................................19 6.3 Results ...................................................................22 7 Performance Comparison ......................................22 8 Conclusions ...........................................................22 9 References .............................................................23 Speech Coder Filters Using the StarCoreTM SC140/SC1400 Cores