Transceiver52M: Replace convolve and related calls with SSE implementation

This large patch replaced the convolve() call with an SSE vector
enabled version. The lower C and SSE intrinsic based code operates
on fixed and aligned vectors for the filter taps. The storage format
of interleaved I/Q for both complex and real vectors is maintained.

SSE filter tap values must:

  1. Start 16-byte aligned
  2. Number with a multiple of 4 between 4 and 20 for real taps
  3. Number with a multiple of 4 for complex taps

Non-compliant values will fall back to non-SSE usage. Fixed length
iterators mean that head and tail cases may require reallocation of
the input vector, which is automatically handled by the upper C++
interface.

Other calls are affected by these changes and adjusted or rewritten
accordingly. The underlying algorithms, however, are unchanged.

  generateGSMPulse()
  analyzeTrafficBurst()
  detectRACHBurst()

Intel SSE configuration is automatically detected and configured at
build time with Autoconf macros.

Signed-off-by: Thomas Tsou <tom@tsou.cc>
diff --git a/Transceiver52M/convolve.h b/Transceiver52M/convolve.h
new file mode 100644
index 0000000..aef9953
--- /dev/null
+++ b/Transceiver52M/convolve.h
@@ -0,0 +1,30 @@
+#ifndef _CONVOLVE_H_
+#define _CONVOLVE_H_
+
+void *convolve_h_alloc(int num);
+
+int convolve_real(float *x, int x_len,
+		  float *h, int h_len,
+		  float *y, int y_len,
+		  int start, int len,
+		  int step, int offset);
+
+int convolve_complex(float *x, int x_len,
+		     float *h, int h_len,
+		     float *y, int y_len,
+		     int start, int len,
+		     int step, int offset);
+
+int base_convolve_real(float *x, int x_len,
+		       float *h, int h_len,
+		       float *y, int y_len,
+		       int start, int len,
+		       int step, int offset);
+
+int base_convolve_complex(float *x, int x_len,
+			  float *h, int h_len,
+			  float *y, int y_len,
+			  int start, int len,
+			  int step, int offset);
+
+#endif /* _CONVOLVE_H_ */