Optimization: mpfr_cmp2 now accepts any combination of real arguments

and computes the sign of |b| - |c| (in addition to the number of
cancelled bits); mpfr_add, mpfr_sub, mpfr_sub1, mpfr_agm and some
tests updated to take this change into account.


git-svn-id: svn://scm.gforge.inria.fr/svn/mpfr/trunk@1641 280ebfd0-de03-0410-8827-d642c229c3f4

1 files changed, 47 insertions, 26 deletions

diff --git a/tests/tcmp2.c b/tests/tcmp2.c
index 61bfaaa1c..70349fd40 100644
--- a/tests/tcmp2.c
+++ b/tests/tcmp2.c
@@ -57,7 +57,8 @@ void
 worst_cases ()
 {
   mpfr_t x, y;
-  unsigned int i, j, k, l, b, expected;
+  unsigned int i, j, k, b, expected;
+  mp_prec_t l;
 
   mpfr_init2 (x, 200);
   mpfr_init2 (y, 200);
@@ -68,24 +69,26 @@ worst_cases ()
       mpfr_set_ui (x, 1, GMP_RNDN);
       mpfr_div_2exp (y, y, 1, GMP_RNDN); /* y = 1/2^i */
 
-      if ((l = mpfr_cmp2 (x, y)) != 1)
+      l = 0;
+      if (mpfr_cmp2 (x, y, &l) <= 0 || l != 1)
 	{
 	  fprintf (stderr, "Error in mpfr_cmp2:\nx=");
 	  mpfr_out_str (stderr, 2, 0, x, GMP_RNDN);
 	  fprintf (stderr, "\ny=");
 	  mpfr_out_str (stderr, 2, 0, y, GMP_RNDN);
-	  fprintf (stderr, "\ngot %u instead of %u\n", l, 1);
+	  fprintf (stderr, "\ngot %lu instead of %u\n", l, 1);
 	  exit(1);
 	}
 
       mpfr_add (x, x, y, GMP_RNDN); /* x = 1 + 1/2^i */
-      if ((l = mpfr_cmp2 (x, y)) != 0)
+      l = 0;
+      if (mpfr_cmp2 (x, y, &l) <= 0 || l != 0)
 	{
 	  fprintf (stderr, "Error in mpfr_cmp2:\nx=");
 	  mpfr_out_str (stderr, 2, 0, x, GMP_RNDN);
 	  fprintf (stderr, "\ny=");
 	  mpfr_out_str (stderr, 2, 0, y, GMP_RNDN);
-	  fprintf (stderr, "\ngot %u instead of %u\n", l, 0);
+	  fprintf (stderr, "\ngot %lu instead of %u\n", l, 0);
 	  exit(1);
 	}
     }
@@ -110,7 +113,7 @@ worst_cases ()
 
 	      set_bit (x, i + j + k + 2, 1);
 	      set_bit (y, i + j + k + 2, 0);
-	      l = mpfr_cmp2 (x, y);
+	      l = 0; mpfr_cmp2 (x, y, &l);
 	      expected = i + j + k + 1;
 	      if (l != expected)
 		{
@@ -118,14 +121,14 @@ worst_cases ()
 		  mpfr_out_str (stderr, 2, 0, x, GMP_RNDN);
 		  fprintf (stderr, "\ny=");
 		  mpfr_out_str (stderr, 2, 0, y, GMP_RNDN);
-		  fprintf (stderr, "\ngot %u instead of %u\n", l, expected);
+		  fprintf (stderr, "\ngot %lu instead of %u\n", l, expected);
 		  exit(1);
 		}
 
 	      set_bit (x, i + j + k + 2, 0);
 	      set_bit (x, i + j + k + 3, 0);
 	      set_bit (y, i + j + k + 3, 1);
-	      l = mpfr_cmp2 (x, y);
+	      l = 0; mpfr_cmp2 (x, y, &l);
 	      expected = i + j + k + 2;
 	      if (l != expected)
 		{
@@ -133,7 +136,7 @@ worst_cases ()
 		  mpfr_out_str (stderr, 2, 0, x, GMP_RNDN);
 		  fprintf (stderr, "\ny=");
 		  mpfr_out_str (stderr, 2, 0, y, GMP_RNDN);
-		  fprintf (stderr, "\ngot %u instead of %u\n", l, expected);
+		  fprintf (stderr, "\ngot %lu instead of %u\n", l, expected);
 		  exit(1);
 		}
 	    }
@@ -148,7 +151,7 @@ void
 tcmp2 (double x, double y, int i)
 {
   mpfr_t xx, yy;
-  int j;
+  mp_prec_t j;
 
   if (i==-1) {
     if (x==y) i=53;
@@ -157,13 +160,25 @@ tcmp2 (double x, double y, int i)
   mpfr_init2(xx, 53); mpfr_init2(yy, 53);
   mpfr_set_d (xx, x, GMP_RNDN);
   mpfr_set_d (yy, y, GMP_RNDN);
-  j = mpfr_cmp2 (xx, yy);
-  if (j != i) {
+  j = 0;
+  if (mpfr_cmp2 (xx, yy, &j) == 0)
+    {
+      if (x != y)
+        {
+          fprintf (stderr, "Error in mpfr_cmp2 for\nx=");
+          mpfr_out_str (stderr, 2, 0, xx, GMP_RNDN);
+          fprintf (stderr, "\ny=");
+          mpfr_out_str (stderr, 2, 0, yy, GMP_RNDN);
+          fprintf (stderr, "\ngot sign 0 for x != y\n");
+          exit(1);
+        }
+    }
+  else if (j != i) {
     fprintf (stderr, "Error in mpfr_cmp2 for\nx=");
     mpfr_out_str (stderr, 2, 0, xx, GMP_RNDN);
     fprintf (stderr, "\ny=");
     mpfr_out_str (stderr, 2, 0, yy, GMP_RNDN);
-    fprintf (stderr, "\ngot %u instead of %u\n", j, i);
+    fprintf (stderr, "\ngot %lu instead of %u\n", j, i);
     exit(1);
   }
   mpfr_clear(xx); mpfr_clear(yy);
@@ -172,7 +187,7 @@ tcmp2 (double x, double y, int i)
 void special ()
 {
   mpfr_t x, y;
-  int j;
+  mp_prec_t j;
 
   mpfr_init (x); mpfr_init (y);
 
@@ -181,7 +196,8 @@ void special ()
   mpfr_set_prec (y, 65);
   mpfr_set_str_raw (x, "0.10000000000000000000000000000000000001110010010110100110011110000E1");
   mpfr_set_str_raw (y, "0.11100100101101001100111011111111110001101001000011101001001010010E-35");
-  if ((j = mpfr_cmp2 (x, y)) != 1) {
+  j = 0;
+  if (mpfr_cmp2 (x, y, &j) <= 0 || j != 1) {
     printf ("Error in mpfr_cmp2:\n");
     printf ("x=");
     mpfr_print_binary (x);
@@ -189,29 +205,31 @@ void special ()
     printf ("y=");
     mpfr_print_binary (y);
     putchar ('\n');
-    printf ("got %d, expected 1\n", j);
+    printf ("got %lu, expected 1\n", j);
     exit (1);
   }
 
   mpfr_set_prec(x, 127); mpfr_set_prec(y, 127);
   mpfr_set_str_raw(x, "0.1011010000110111111000000101011110110001000101101011011110010010011110010000101101000010011001100110010000000010110000101000101E6");
   mpfr_set_str_raw(y, "0.1011010000110111111000000101011011111100011101000011001111000010100010100110110100110010011001100110010000110010010110000010110E6");
-  if ((j=mpfr_cmp2(x, y)) != 32) {
+  j = 0;
+  if (mpfr_cmp2(x, y, &j) <= 0 || j != 32) {
     printf("Error in mpfr_cmp2:\n");
     printf("x="); mpfr_print_binary(x); putchar('\n');
     printf("y="); mpfr_print_binary(y); putchar('\n');
-    printf("got %d, expected 32\n", j);
+    printf("got %lu, expected 32\n", j);
     exit(1);
   }
 
   mpfr_set_prec (x, 128); mpfr_set_prec (y, 239);
   mpfr_set_str_raw (x, "0.10001000110110000111011000101011111100110010010011001101000011111010010110001000000010100110100111111011011010101100100000000000E167");
   mpfr_set_str_raw (y, "0.10001000110110000111011000101011111100110010010011001101000011111010010110001000000010100110100111111011011010101100011111111111111111111111111111111111111111111111011111100101011100011001101000100111000010000000000101100110000111111000101E167");
-  if ((j=mpfr_cmp2(x, y)) != 164) {
+  j = 0;
+  if (mpfr_cmp2(x, y, &j) <= 0 || j != 164) {
     printf("Error in mpfr_cmp2:\n");
     printf("x="); mpfr_print_binary(x); putchar('\n');
     printf("y="); mpfr_print_binary(y); putchar('\n');
-    printf("got %d, expected 164\n", j);
+    printf("got %lu, expected 164\n", j);
     exit(1);
   }
 
@@ -219,11 +237,12 @@ void special ()
   mpfr_set_prec (x, 130); mpfr_set_prec (y, 130);
   mpfr_set_str_raw (x, "0.1100000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000E2");
   mpfr_set_str_raw (y, "0.1011111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111100E2");
-  if ((j=mpfr_cmp2(x, y)) != 127) {
+  j = 0;
+  if (mpfr_cmp2(x, y, &j) <= 0 || j != 127) {
     printf("Error in mpfr_cmp2:\n");
     printf("x="); mpfr_print_binary(x); putchar('\n');
     printf("y="); mpfr_print_binary(y); putchar('\n');
-    printf("got %d, expected 127\n", j);
+    printf("got %lu, expected 127\n", j);
     exit(1);
   }
 
@@ -231,11 +250,12 @@ void special ()
   mpfr_set_prec (x, 65); mpfr_set_prec (y, 65);
   mpfr_set_ui (x, 5, GMP_RNDN);
   mpfr_set_str_raw (y, "0.10011111111111111111111111111111111111111111111111111111111111101E3");
-  if ((j=mpfr_cmp2(x, y)) != 63) {
+  j = 0;
+  if (mpfr_cmp2(x, y, &j) <= 0 || j != 63) {
     printf("Error in mpfr_cmp2:\n");
     printf("x="); mpfr_print_binary(x); putchar('\n');
     printf("y="); mpfr_print_binary(y); putchar('\n');
-    printf("got %d, expected 63\n", j);
+    printf("got %lu, expected 63\n", j);
     exit(1);
   }
 
@@ -243,11 +263,12 @@ void special ()
   mpfr_set_prec (x, 65); mpfr_set_prec (y, 65);
   mpfr_set_str_raw (x, "0.10011011111000101001110000000000000000000000000000000000000000000E-69");
   mpfr_set_str_raw (y, "0.10011011111000101001101111111111111111111111111111111111111111101E-69");
-  if ((j=mpfr_cmp2(x, y)) != 63) {
+  j = 0;
+  if (mpfr_cmp2(x, y, &j) <= 0 || j != 63) {
     printf("Error in mpfr_cmp2:\n");
     printf("x="); mpfr_print_binary(x); putchar('\n');
     printf("y="); mpfr_print_binary(y); putchar('\n');
-    printf("got %d, expected 63\n", j);
+    printf("got %lu, expected 63\n", j);
     exit(1);
   }