[committed] Remove sh5media divtab code

[committed] Remove sh5media divtab code

[Jeff Law]

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Spurred by Akari Takahashi's patch to config/sh/divtab.cc, this removes 
divtab.cc completely.

divtab.cc was used to calculate a division table for the sh5 media 
processor.  GCC dropped support for that (unmanufactured) chip back in 
2016 and this file simply got missed AFAICT.

Pushed to the trunk,
Jeff

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commit 99dec205a12f7dfa39fd43fc7c36d9974aaec526
Author: Jeff Law <jlaw@ventanamicro.com>
Date:   Tue Jun 13 11:10:21 2023 -0600

    Remove sh5media divtab code
    
    Spurred by Akari Takahashi's patch to config/sh/divtab.cc, this removes
    divtab.cc completely.
    
    divtab.cc was used to calculate a division table for the sh5 media
    processor.  GCC dropped support for that (unmanufactured) chip back
    in 2016 and this file simply got missed AFAICT.
    
    gcc/
            * config/sh/divtab.cc: Remove.

diff --git a/gcc/config/sh/divtab.cc b/gcc/config/sh/divtab.cc
deleted file mode 100644
index a69dd541370..00000000000
--- a/gcc/config/sh/divtab.cc
+++ /dev/null
@@ -1,203 +0,0 @@
-/* Copyright (C) 2003-2023 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 SH5Media integer division
-   Contributed by Joern Rennecke
-   joern.rennecke@superh.com  */
-
-#include <stdio.h>
-#include <math.h>
-
-#define BITS 5
-#define N_ENTRIES (1 << BITS)
-#define CUTOFF_BITS 20
-
-#define BIAS (-330)
-
-double max_defect = 0.;
-double max_defect_x;
-
-double min_defect = 1e9;
-double min_defect_x;
-
-double max_defect2 = 0.;
-double max_defect2_x;
-
-double min_defect2 = 0.;
-double min_defect2_x;
-
-double min_defect3 = 01e9;
-double min_defect3_x;
-int min_defect3_val;
-
-double max_defect3 = 0.;
-double max_defect3_x;
-int max_defect3_val;
-
-static double
-note_defect3 (int val, double d2, double y2d, double x)
-{
-  int cutoff_val = val >> CUTOFF_BITS;
-  double cutoff;
-  double defect;
-
-  if (val < 0)
-    cutoff_val++;
-  cutoff = (cutoff_val * (1<<CUTOFF_BITS) - val) * y2d;
-  defect = cutoff + val * d2;
-  if (val < 0)
-    defect = - defect;
-  if (defect > max_defect3)
-    {
-      max_defect3 = defect;
-      max_defect3_x = x;
-      max_defect3_val = val;
-    }
-  if (defect < min_defect3)
-    {
-      min_defect3 = defect;
-      min_defect3_x = x;
-      min_defect3_val = val;
-    }
-}
-
-/* This function assumes 32-bit integers.  */
-static double
-calc_defect (double x, int constant, int factor)
-{
-  double y0 = (constant - (int) floor ((x * factor * 64.))) / 16384.;
-  double y1 = 2 * y0 -y0 * y0 * (x + BIAS / (1.*(1LL<<30)));
-  double y2d0, y2d;
-  int y2d1;
-  double d, d2;
-
-  y1 = floor (y1 * (1024 * 1024 * 1024)) / (1024 * 1024 * 1024);
-  d = y1 - 1 / x;
-  if (d > max_defect)
-    {
-      max_defect = d;
-      max_defect_x = x;
-    }
-  if (d < min_defect)
-    {
-      min_defect = d;
-      min_defect_x = x;
-    }
-  y2d0 = floor (y1 * x * (1LL << 60-16));
-  y2d1 = (int) (long long) y2d0;
-  y2d = - floor ((y1 - y0 / (1<<30-14)) * y2d1) / (1LL<<44);
-  d2 = y1 + y2d - 1/x;
-  if (d2 > max_defect2)
-    {
-      max_defect2 = d2;
-      max_defect2_x = x;
-    }
-  if (d2 < min_defect2)
-    {
-      min_defect2 = d2;
-      min_defect2_x = x;
-    }
-  /* zero times anything is trivially zero.  */
-  note_defect3 ((1 << CUTOFF_BITS) - 1, d2, y2d, x);
-  note_defect3 (1 << CUTOFF_BITS, d2, y2d, x);
-  note_defect3 ((1U << 31) - (1 << CUTOFF_BITS), d2, y2d, x);
-  note_defect3 ((1U << 31) - 1, d2, y2d, x);
-  note_defect3 (-1, d2, y2d, x);
-  note_defect3 (-(1 << CUTOFF_BITS), d2, y2d, x);
-  note_defect3 ((1U << 31) - (1 << CUTOFF_BITS) + 1, d2, y2d, x);
-  note_defect3 (-(1U << 31), d2, y2d, x);
-  return d;
-}
-
-int
-main ()
-{
-  int i;
-  unsigned char factors[N_ENTRIES];
-  short constants[N_ENTRIES];
-  int steps = N_ENTRIES / 2;
-  double step = 1. / steps;
-  double eps30 = 1. / (1024 * 1024 * 1024);
-
-  for (i = 0; i < N_ENTRIES; i++)
-    {
-      double x_low = (i < steps ? 1. : -3.) + i * step;
-      double x_high = x_low + step - eps30;
-      double x_med;
-      int factor, constant;
-      double low_defect, med_defect, high_defect, max_defect;
-
-      factor = (1./x_low- 1./x_high) / step * 256. + 0.5;
-      if (factor == 256)
-	factor = 255;
-      factors[i] = factor;
-      /* Use minimum of error function for x_med.  */
-      x_med = sqrt (256./factor);
-      if (x_low < 0)
-	x_med = - x_med;
-      low_defect = 1. / x_low + x_low * factor / 256.;
-      high_defect = 1. / x_high + x_high * factor / 256.;
-      med_defect = 1. / x_med + x_med * factor / 256.;
-      max_defect
-	= ((low_defect > high_defect) ^ (x_med < 0)) ? low_defect : high_defect;
-      constant = (med_defect + max_defect) * 0.5 * 16384. + 0.5;
-      if (constant < -32768 || constant > 32767)
-	abort ();
-      constants[i] = constant;
-      calc_defect (x_low, constant, factor);
-      calc_defect (x_med, constant, factor);
-      calc_defect (x_high, constant, factor);
-    }
-    printf ("/* This table has been generated by divtab.cc .\n");
-    printf ("Defects for bias %d:\n", BIAS);
-    printf ("   Max defect: %e at %e\n", max_defect, max_defect_x);
-    printf ("   Min defect: %e at %e\n", min_defect, min_defect_x);
-    printf ("   Max 2nd step defect: %e at %e\n", max_defect2, max_defect2_x);
-    printf ("   Min 2nd step defect: %e at %e\n", min_defect2, min_defect2_x);
-    printf ("   Max div defect: %e at %d:%e\n", max_defect3, max_defect3_val,
-						max_defect3_x);
-    printf ("   Min div defect: %e at %d:%e\n", min_defect3, min_defect3_val,
-						min_defect3_x);
-    printf ("   Defect at 1: %e\n",
-	    calc_defect (1., constants[0], factors[0]));
-    printf ("   Defect at -2: %e */\n",
-	    calc_defect (-2., constants[steps], factors[steps]));
-    printf ("\t.section\t.rodata\n");
-    printf ("\t.balign 2\n");
-    printf ("/* negative division constants */\n");
-    for (i = steps; i < 2 * steps; i++)
-      printf ("\t.word\t%d\n", constants[i]);
-    printf ("/* negative division factors */\n");
-    for (i = steps; i < 2*steps; i++)
-      printf ("\t.byte\t%d\n", factors[i]);
-    printf ("\t.skip %d\n", steps);
-    printf ("\t.global	GLOBAL(div_table):\n");
-    printf ("GLOBAL(div_table):\n");
-    printf ("\t.skip %d\n", steps);
-    printf ("/* positive division factors */\n");
-    for (i = 0; i < steps; i++)
-      printf ("\t.byte\t%d\n", factors[i]);
-    printf ("/* positive division constants */\n");
-    for (i = 0; i < steps; i++)
-      printf ("\t.word\t%d\n", constants[i]);
-  exit (0);
-}