1 files changed, 34 insertions, 0 deletions

diff --git a/generate_table.c b/generate_table.c
new file mode 100644
index 0000000..c7a9d0c
--- /dev/null
+++ b/generate_table.c
@@ -0,0 +1,34 @@
+#include <math.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+// s(-1) n(14) off(+1)   x =   x - ( x >> 14 )
+// s( 1) n(-4) off( 0)   x =       ( x <<  4 )
+// s( 1) n( 8) off(-1)   x = - x + ( x <<  8 )
+
+int main() {
+  int n, m, nsign;
+
+  // loop over all constructs in the form +-1*x^+-2n, n=-31..+31
+  for (n=-31; n<= 31; ++n )
+    for ( nsign=-1; nsign<=1; nsign+=2 )
+    {
+      // The one term only case
+      double v = (double)nsign * pow( 2.f, (double)n );
+      if( v > 0.f )
+          printf( "%0+25.21lf %08X x =             %s ( x %s %2d )%s\n", log(v), abs((int)(67108864.f*log(v))), nsign==-1?"-":" ", n>=0?"<<":">>", (int)abs(n), " !RECOMMENDED!" );
+
+      // Loop over second term
+      for (m=-31; m<=31; ++m )
+      {
+        double v = pow( 2.f, (double)m ) + (double)nsign * pow( 2.f, (double)n );
+        if( v > 0.f ) {
+          printf( "%0+25.21lf %08X x = ( x %s %2d ) %s ( x %s %2d )%s\n", log(v), abs((int)(67108864.f*log(v))), m>=0?"<<":">>", (int)abs(m), nsign==-1?"-":"+", n>=0?"<<":">>", (int)abs(n), n*m?"":" !RECOMMENDED!" );
+          if( v < 1.f )
+              printf( "%0+25.21lf %08X x-= ( x %s %2d ) %s ( x %s %2d )\n", log(1.0f - v), abs((int)(67108864.f*log(1.0f - v))), m>=0?"<<":">>", (int)abs(m), nsign==-1?"-":"+", n>=0?"<<":">>", (int)abs(n) );
+        }
+      }
+    }
+
+  return 0;
+}