Imported gcc-4.4.3

[msp430-gcc.git] / gcc / config / sh / divtab-sh4.c

diff --git a/gcc/config/sh/divtab-sh4.c b/gcc/config/sh/divtab-sh4.c
new file mode 100644 (file)
index 0000000..7585081
--- /dev/null
+++ b/gcc/config/sh/divtab-sh4.c
@@ -0,0 +1,85 @@
+/* Copyright (C) 2004, 2009 Free Software Foundation, Inc.
+
+This file is free software; you can redistribute it and/or modify it
+under the terms of the GNU General Public License as published by the
+Free Software Foundation; either version 3, or (at your option) any
+later version.
+
+This file is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+General Public License for more details.
+
+Under Section 7 of GPL version 3, you are granted additional
+permissions described in the GCC Runtime Library Exception, version
+3.1, as published by the Free Software Foundation.
+
+You should have received a copy of the GNU General Public License and
+a copy of the GCC Runtime Library Exception along with this program;
+see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+<http://www.gnu.org/licenses/>.  */
+
+/* Calculate division table for SH2..4 integer division
+   Contributed by Joern Rernnecke
+   joern.rennecke@superh.com  */
+
+#include <stdio.h>
+#include <math.h>
+
+int
+main ()
+{
+  int i, j;
+  double q, r, err, max_err = 0, max_s_err = 0;
+
+  puts("/* This table has been generated by divtab-sh4.c.  */");
+  puts ("\t.balign 4");
+  puts ("LOCAL(div_table_clz):");
+  /* output some dummy number for 1/0.  */
+  printf ("\t.byte\t%d\n", 0);
+  for (i = 1; i <= 128; i++)
+    {
+      int n = 0;
+      if (i == 128)
+       puts ("\
+/* Lookup table translating positive divisor to index into table of\n\
+   normalized inverse.  N.B. the '0' entry is also the last entry of the\n\
+ previous table, and causes an unaligned access for division by zero.  */\n\
+LOCAL(div_table_ix):");
+      for (j = i; j <= 128; j += j)
+       n++;
+      printf ("\t.byte\t%d\n", n - 7);
+    }
+  for (i = 1; i <= 128; i++)
+    {
+      j = i < 0 ? -i : i;
+      while (j < 128)
+       j += j;
+      printf ("\t.byte\t%d\n", j * 2 - 96*4);
+    }
+  puts("\
+/* 1/64 .. 1/127, normalized.  There is an implicit leading 1 in bit 32.  */\n\
+       .balign 4\n\
+LOCAL(zero_l):");
+  for (i = 64; i < 128; i++)
+    {
+      if (i == 96)
+       puts ("LOCAL(div_table):");
+      q = 4.*(1<<30)*128/i;
+      r = ceil (q);
+      /* The value for 64 is actually differently scaled that it would
+        appear from this calculation.  The implicit part is %01, not 10.
+        Still, since the value in the table is 0 either way, this
+        doesn't matter here.  Still, the 1/64 entry is effectively a 1/128
+        entry.  */
+      printf ("\t.long\t0x%X\n", (unsigned) r);
+      err = r - q;
+      if (err > max_err)
+       max_err = err;
+      err = err * i / 128;
+      if (err > max_s_err)
+       max_s_err = err;
+    }
+  printf ("\t/* maximum error: %f scaled: %f*/\n", max_err, max_s_err);
+  exit (0);
+}