divtab-sh4.c, [...]: New files.

2006-03-23  J"orn Rennecke <joern.rennecke@st.com>

	* config/sh/divtab-sh4.c, config/sh/divcost-analysis: New files.
	* config/sh/lib1funcs.asm (div_table): Add !__SH5__ variant.
	* config/sh/t-sh (LIB1ASMFUNCS): Add _div_table.
	* config/sh/sh.opt (mdiv=): Amend description.
	* config/sh/sh.h (TARGET_DIVIDE_CALL_DIV1): New macro.
	(TARGET_DIVIDE_CALL_FP, TARGET_DIVIDE_CALL_TABLE): Likewise.
	(sh_divide_strategy_e): Add new members SH_DIV_CALL_DIV1,
	SH_DIV_CALL_FP, SH_DIV_CALL_TABLE and SH_DIV_INTRINSIC.
	(OVERRIDE_OPTIONS): Also process sh_div_str for TARGET_SH1.
	Calculate sh_divsi3_libfunc using TARGET_DIVIDE_* macros.
	* config/sh/sh.md (udivsi3_i4_int, divsi3_i4_int): New patterns.
	(udivsi3, divsi3): Use them.  Check TARGET_DIVIDE_CALL_TABLE /
	TARGET_DIVIDE_CALL_FP.

From-SVN: r112331

1 files changed, 90 insertions, 0 deletions

diff --git a/gcc/config/sh/divtab-sh4.c b/gcc/config/sh/divtab-sh4.c
new file mode 100644
index 0000000..e7de6c4
--- /dev/null
+++ b/gcc/config/sh/divtab-sh4.c
@@ -0,0 +1,90 @@
+/* Copyright (C) 2004 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 2, or (at your option) any
+later version.
+
+In addition to the permissions in the GNU General Public License, the
+Free Software Foundation gives you unlimited permission to link the
+compiled version of this file into combinations with other programs,
+and to distribute those combinations without any restriction coming
+from the use of this file.  (The General Public License restrictions
+do apply in other respects; for example, they cover modification of
+the file, and distribution when not linked into a combine
+executable.)
+
+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.
+
+You should have received a copy of the GNU General Public License
+along with this program; see the file COPYING.  If not, write to
+the Free Software Foundation, 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA.  */
+
+/* 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);
+}