Subversion Repositories openrisc_2011-10-31

/* Simple bitmaps.

   Copyright (C) 1999, 2000, 2002, 2003, 2004, 2006, 2007, 2008

   Free Software Foundation, Inc.

This file is part of GCC.

GCC 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.

GCC 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 GCC; see the file COPYING3.  If not see

<http://www.gnu.org/licenses/>.  */

#include "config.h"

#include "system.h"

#include "coretypes.h"

#include "tm.h"

#include "rtl.h"

#include "flags.h"

#include "hard-reg-set.h"

#include "obstack.h"

#include "basic-block.h"

#if GCC_VERSION >= 3400

#if HOST_BITS_PER_WIDEST_FAST_INT == HOST_BITS_PER_LONG

#define do_popcount(x) __builtin_popcountl(x)

#elif HOST_BITS_PER_WIDEST_FAST_INT == HOST_BITS_PER_LONGLONG

#define do_popcount(x) __builtin_popcountll(x)

#else

#error "internal error: sbitmap.h and hwint.h are inconsistent"

#endif

#else

static unsigned long sbitmap_elt_popcount (SBITMAP_ELT_TYPE);

#define do_popcount(x) sbitmap_elt_popcount((x))

#endif

/* This macro controls debugging that is as expensive as the

   operations it verifies.  */

/* #define BITMAP_DEBUGGING  */

#ifdef BITMAP_DEBUGGING

/* Verify the population count of sbitmap A matches the cached value,

   if there is a cached value. */

void

sbitmap_verify_popcount (const_sbitmap a)

{

  unsigned ix;

  unsigned int lastword;

  if (!a->popcount)

    return;

  lastword = a->size;

  for (ix = 0; ix < lastword; ix++)

    gcc_assert (a->popcount[ix] == do_popcount (a->elms[ix]));

}

#endif

/* Bitmap manipulation routines.  */

/* Allocate a simple bitmap of N_ELMS bits.  */

sbitmap

sbitmap_alloc (unsigned int n_elms)

{

  unsigned int bytes, size, amt;

  sbitmap bmap;

  size = SBITMAP_SET_SIZE (n_elms);

  bytes = size * sizeof (SBITMAP_ELT_TYPE);

  amt = (sizeof (struct simple_bitmap_def)

         + bytes - sizeof (SBITMAP_ELT_TYPE));

  bmap = (sbitmap) xmalloc (amt);

  bmap->n_bits = n_elms;

  bmap->size = size;

  bmap->popcount = NULL;

  return bmap;

}

/* Allocate a simple bitmap of N_ELMS bits, and a popcount array.  */

sbitmap

sbitmap_alloc_with_popcount (unsigned int n_elms)

{

  sbitmap const bmap = sbitmap_alloc (n_elms);

  bmap->popcount = XNEWVEC (unsigned char, bmap->size);

  return bmap;

}

/* Resize a simple bitmap BMAP to N_ELMS bits.  If increasing the

   size of BMAP, clear the new bits to zero if the DEF argument

   is zero, and set them to one otherwise.  */

sbitmap

sbitmap_resize (sbitmap bmap, unsigned int n_elms, int def)

{

  unsigned int bytes, size, amt;

  unsigned int last_bit;

  size = SBITMAP_SET_SIZE (n_elms);

  bytes = size * sizeof (SBITMAP_ELT_TYPE);

  if (bytes > SBITMAP_SIZE_BYTES (bmap))

    {

      amt = (sizeof (struct simple_bitmap_def)

            + bytes - sizeof (SBITMAP_ELT_TYPE));

      bmap = (sbitmap) xrealloc (bmap, amt);

      if (bmap->popcount)

        bmap->popcount = XRESIZEVEC (unsigned char, bmap->popcount, size);

    }

  if (n_elms > bmap->n_bits)

    {

      if (def)

        {

          memset (bmap->elms + bmap->size, -1,

                  bytes - SBITMAP_SIZE_BYTES (bmap));

          /* Set the new bits if the original last element.  */

          last_bit = bmap->n_bits % SBITMAP_ELT_BITS;

          if (last_bit)

            bmap->elms[bmap->size - 1]

              |= ~((SBITMAP_ELT_TYPE)-1 >> (SBITMAP_ELT_BITS - last_bit));

          /* Clear the unused bit in the new last element.  */

          last_bit = n_elms % SBITMAP_ELT_BITS;

          if (last_bit)

            bmap->elms[size - 1]

              &= (SBITMAP_ELT_TYPE)-1 >> (SBITMAP_ELT_BITS - last_bit);

        }

      else

        {

          memset (bmap->elms + bmap->size, 0,

                  bytes - SBITMAP_SIZE_BYTES (bmap));

          if (bmap->popcount)

            memset (bmap->popcount + bmap->size, 0,

                    (size * sizeof (unsigned char))

                    - (bmap->size * sizeof (unsigned char)));

        }

    }

  else if (n_elms < bmap->n_bits)

    {

      /* Clear the surplus bits in the last word.  */

      last_bit = n_elms % SBITMAP_ELT_BITS;

      if (last_bit)

        {

          bmap->elms[size - 1]

            &= (SBITMAP_ELT_TYPE)-1 >> (SBITMAP_ELT_BITS - last_bit);

          if (bmap->popcount)

            bmap->popcount[size - 1] = do_popcount (bmap->elms[size - 1]);

        }

    }

  bmap->n_bits = n_elms;

  bmap->size = size;

  return bmap;

}

/* Re-allocate a simple bitmap of N_ELMS bits. New storage is uninitialized.  */

sbitmap

sbitmap_realloc (sbitmap src, unsigned int n_elms)

{

  unsigned int bytes, size, amt;

  sbitmap bmap;

  size = SBITMAP_SET_SIZE (n_elms);

  bytes = size * sizeof (SBITMAP_ELT_TYPE);

  amt = (sizeof (struct simple_bitmap_def)

         + bytes - sizeof (SBITMAP_ELT_TYPE));

  if (SBITMAP_SIZE_BYTES (src)  >= bytes)

    {

      src->n_bits = n_elms;

      return src;

    }

  bmap = (sbitmap) xrealloc (src, amt);

  bmap->n_bits = n_elms;

  bmap->size = size;

  return bmap;

}

/* Allocate a vector of N_VECS bitmaps of N_ELMS bits.  */

sbitmap *

sbitmap_vector_alloc (unsigned int n_vecs, unsigned int n_elms)

{

  unsigned int i, bytes, offset, elm_bytes, size, amt, vector_bytes;

  sbitmap *bitmap_vector;

  size = SBITMAP_SET_SIZE (n_elms);

  bytes = size * sizeof (SBITMAP_ELT_TYPE);

  elm_bytes = (sizeof (struct simple_bitmap_def)

               + bytes - sizeof (SBITMAP_ELT_TYPE));

  vector_bytes = n_vecs * sizeof (sbitmap *);

  /* Round up `vector_bytes' to account for the alignment requirements

     of an sbitmap.  One could allocate the vector-table and set of sbitmaps

     separately, but that requires maintaining two pointers or creating

     a cover struct to hold both pointers (so our result is still just

     one pointer).  Neither is a bad idea, but this is simpler for now.  */

  {

    /* Based on DEFAULT_ALIGNMENT computation in obstack.c.  */

    struct { char x; SBITMAP_ELT_TYPE y; } align;

    int alignment = (char *) & align.y - & align.x;

    vector_bytes = (vector_bytes + alignment - 1) & ~ (alignment - 1);

  }

  amt = vector_bytes + (n_vecs * elm_bytes);

  bitmap_vector = (sbitmap *) xmalloc (amt);

  for (i = 0, offset = vector_bytes; i < n_vecs; i++, offset += elm_bytes)

    {

      sbitmap b = (sbitmap) ((char *) bitmap_vector + offset);

      bitmap_vector[i] = b;

      b->n_bits = n_elms;

      b->size = size;

      b->popcount = NULL;

    }

  return bitmap_vector;

}

/* Copy sbitmap SRC to DST.  */

void

sbitmap_copy (sbitmap dst, const_sbitmap src)

{

  memcpy (dst->elms, src->elms, sizeof (SBITMAP_ELT_TYPE) * dst->size);

  if (dst->popcount)

    memcpy (dst->popcount, src->popcount, sizeof (unsigned char) * dst->size);

}

/* Copy the first N elements of sbitmap SRC to DST.  */

void

sbitmap_copy_n (sbitmap dst, const_sbitmap src, unsigned int n)

{

  memcpy (dst->elms, src->elms, sizeof (SBITMAP_ELT_TYPE) * n);

  if (dst->popcount)

    memcpy (dst->popcount, src->popcount, sizeof (unsigned char) * n);

}

/* Determine if a == b.  */

int

sbitmap_equal (const_sbitmap a, const_sbitmap b)

{

  return !memcmp (a->elms, b->elms, sizeof (SBITMAP_ELT_TYPE) * a->size);

}

/* Return true if the bitmap is empty.  */

bool

sbitmap_empty_p (const_sbitmap bmap)

{

  unsigned int i;

  for (i=0; i<bmap->size; i++)

    if (bmap->elms[i])

      return false;

  return true;

}

/* Return false if any of the N bits are set in MAP starting at

   START.  */

bool

sbitmap_range_empty_p (const_sbitmap bmap, unsigned int start, unsigned int n)

{

  unsigned int i = start / SBITMAP_ELT_BITS;

  SBITMAP_ELT_TYPE elm;

  unsigned int shift = start % SBITMAP_ELT_BITS;

  gcc_assert (bmap->n_bits >= start + n);

  elm = bmap->elms[i];

  elm = elm >> shift;

  if (shift + n <= SBITMAP_ELT_BITS)

    {

      /* The bits are totally contained in a single element.  */

      if (shift + n < SBITMAP_ELT_BITS)

        elm &= ((1 << n) - 1);

      return (elm == 0);

    }

  if (elm)

    return false;

  n -= SBITMAP_ELT_BITS - shift;

  i++;

  /* Deal with full elts.  */

  while (n >= SBITMAP_ELT_BITS)

    {

      if (bmap->elms[i])

        return false;

      i++;

      n -= SBITMAP_ELT_BITS;

    }

  /* The leftover bits.  */

  if (n)

    {

      elm = bmap->elms[i];

      elm &= ((1 << n) - 1);

      return (elm == 0);

    }

  return true;

}

/* Zero all elements in a bitmap.  */

void

sbitmap_zero (sbitmap bmap)

{

  memset (bmap->elms, 0, SBITMAP_SIZE_BYTES (bmap));

  if (bmap->popcount)

    memset (bmap->popcount, 0, bmap->size * sizeof (unsigned char));

}

/* Set all elements in a bitmap to ones.  */

void

sbitmap_ones (sbitmap bmap)

{

  unsigned int last_bit;

  memset (bmap->elms, -1, SBITMAP_SIZE_BYTES (bmap));

  if (bmap->popcount)

    memset (bmap->popcount, -1, bmap->size * sizeof (unsigned char));

  last_bit = bmap->n_bits % SBITMAP_ELT_BITS;

  if (last_bit)

    {

      bmap->elms[bmap->size - 1]

        = (SBITMAP_ELT_TYPE)-1 >> (SBITMAP_ELT_BITS - last_bit);

      if (bmap->popcount)

        bmap->popcount[bmap->size - 1]

          = do_popcount (bmap->elms[bmap->size - 1]);

    }

}

/* Zero a vector of N_VECS bitmaps.  */

void

sbitmap_vector_zero (sbitmap *bmap, unsigned int n_vecs)

{

  unsigned int i;

  for (i = 0; i < n_vecs; i++)

    sbitmap_zero (bmap[i]);

}

/* Set a vector of N_VECS bitmaps to ones.  */

void

sbitmap_vector_ones (sbitmap *bmap, unsigned int n_vecs)

{

  unsigned int i;

  for (i = 0; i < n_vecs; i++)

    sbitmap_ones (bmap[i]);

}

/* Set DST to be A union (B - C).

   DST = A | (B & ~C).

   Returns true if any change is made.  */

bool

sbitmap_union_of_diff_cg (sbitmap dst, const_sbitmap a, const_sbitmap b, const_sbitmap c)

{

  unsigned int i, n = dst->size;

  sbitmap_ptr dstp = dst->elms;

  const_sbitmap_ptr ap = a->elms;

  const_sbitmap_ptr bp = b->elms;

  const_sbitmap_ptr cp = c->elms;

  SBITMAP_ELT_TYPE changed = 0;

  gcc_assert (!dst->popcount);

  for (i = 0; i < n; i++)

    {

      const SBITMAP_ELT_TYPE tmp = *ap++ | (*bp++ & ~*cp++);

      changed |= *dstp ^ tmp;

      *dstp++ = tmp;

    }

  return changed != 0;

}

void

sbitmap_union_of_diff (sbitmap dst, const_sbitmap a, const_sbitmap b, const_sbitmap c)

{

  unsigned int i, n = dst->size;

  sbitmap_ptr dstp = dst->elms;

  const_sbitmap_ptr ap = a->elms;

  const_sbitmap_ptr bp = b->elms;

  const_sbitmap_ptr cp = c->elms;

  gcc_assert (!dst->popcount && !a->popcount

              && !b->popcount && !c->popcount);

  for (i = 0; i < n; i++)

    *dstp++ = *ap++ | (*bp++ & ~*cp++);

}

/* Set bitmap DST to the bitwise negation of the bitmap SRC.  */

void

sbitmap_not (sbitmap dst, const_sbitmap src)

{

  unsigned int i, n = dst->size;

  sbitmap_ptr dstp = dst->elms;

  const_sbitmap_ptr srcp = src->elms;

  unsigned int last_bit;

  gcc_assert (!dst->popcount);

  for (i = 0; i < n; i++)

    *dstp++ = ~*srcp++;

  /* Zero all bits past n_bits, by ANDing dst with sbitmap_ones.  */

  last_bit = src->n_bits % SBITMAP_ELT_BITS;

  if (last_bit)

    dst->elms[n-1] = dst->elms[n-1]

      & ((SBITMAP_ELT_TYPE)-1 >> (SBITMAP_ELT_BITS - last_bit));

}

/* Set the bits in DST to be the difference between the bits

   in A and the bits in B. i.e. dst = a & (~b).  */

void

sbitmap_difference (sbitmap dst, const_sbitmap a, const_sbitmap b)

{

  unsigned int i, dst_size = dst->size;

  unsigned int min_size = dst->size;

  sbitmap_ptr dstp = dst->elms;

  const_sbitmap_ptr ap = a->elms;

  const_sbitmap_ptr bp = b->elms;

  gcc_assert (!dst->popcount);

  /* A should be at least as large as DEST, to have a defined source.  */

  gcc_assert (a->size >= dst_size);

  /* If minuend is smaller, we simply pretend it to be zero bits, i.e.

     only copy the subtrahend into dest.  */

  if (b->size < min_size)

    min_size = b->size;

  for (i = 0; i < min_size; i++)

    *dstp++ = *ap++ & (~*bp++);

  /* Now fill the rest of dest from A, if B was too short.

     This makes sense only when destination and A differ.  */

  if (dst != a && i != dst_size)

    for (; i < dst_size; i++)

      *dstp++ = *ap++;

}

/* Return true if there are any bits set in A are also set in B.

   Return false otherwise.  */

bool

sbitmap_any_common_bits (const_sbitmap a, const_sbitmap b)

{

  const_sbitmap_ptr ap = a->elms;

  const_sbitmap_ptr bp = b->elms;

  unsigned int i, n;

  n = MIN (a->size, b->size);

  for (i = 0; i < n; i++)

    if ((*ap++ & *bp++) != 0)

      return true;

  return false;

}

/* Set DST to be (A and B).

   Return nonzero if any change is made.  */

bool

sbitmap_a_and_b_cg (sbitmap dst, const_sbitmap a, const_sbitmap b)

{

  unsigned int i, n = dst->size;

  sbitmap_ptr dstp = dst->elms;

  const_sbitmap_ptr ap = a->elms;

  const_sbitmap_ptr bp = b->elms;

  SBITMAP_ELT_TYPE changed = 0;

  gcc_assert (!dst->popcount);

  for (i = 0; i < n; i++)

    {

      const SBITMAP_ELT_TYPE tmp = *ap++ & *bp++;

      changed |= *dstp ^ tmp;

      *dstp++ = tmp;

    }

  return changed != 0;

}

void

sbitmap_a_and_b (sbitmap dst, const_sbitmap a, const_sbitmap b)

{

  unsigned int i, n = dst->size;

  sbitmap_ptr dstp = dst->elms;

  const_sbitmap_ptr ap = a->elms;

  const_sbitmap_ptr bp = b->elms;

  bool has_popcount = dst->popcount != NULL;

  unsigned char *popcountp = dst->popcount;

  for (i = 0; i < n; i++)

    {

      const SBITMAP_ELT_TYPE tmp = *ap++ & *bp++;

      if (has_popcount)

        {

          bool wordchanged = (*dstp ^ tmp) != 0;

          if (wordchanged)

            *popcountp = do_popcount (tmp);

          popcountp++;

        }

      *dstp++ = tmp;

    }

#ifdef BITMAP_DEBUGGING

  if (has_popcount)

    sbitmap_verify_popcount (dst);

#endif

}

/* Set DST to be (A xor B)).

   Return nonzero if any change is made.  */

bool

sbitmap_a_xor_b_cg (sbitmap dst, const_sbitmap a, const_sbitmap b)

{

  unsigned int i, n = dst->size;

  sbitmap_ptr dstp = dst->elms;

  const_sbitmap_ptr ap = a->elms;

  const_sbitmap_ptr bp = b->elms;

  SBITMAP_ELT_TYPE changed = 0;

  gcc_assert (!dst->popcount);

  for (i = 0; i < n; i++)

    {

      const SBITMAP_ELT_TYPE tmp = *ap++ ^ *bp++;

      changed |= *dstp ^ tmp;

      *dstp++ = tmp;

    }

  return changed != 0;

}

void

sbitmap_a_xor_b (sbitmap dst, const_sbitmap a, const_sbitmap b)

{

  unsigned int i, n = dst->size;

  sbitmap_ptr dstp = dst->elms;

  const_sbitmap_ptr ap = a->elms;

  const_sbitmap_ptr bp = b->elms;

  bool has_popcount = dst->popcount != NULL;

  unsigned char *popcountp = dst->popcount;

  for (i = 0; i < n; i++)

    {

      const SBITMAP_ELT_TYPE tmp = *ap++ ^ *bp++;

      if (has_popcount)

        {

          bool wordchanged = (*dstp ^ tmp) != 0;

          if (wordchanged)

            *popcountp = do_popcount (tmp);

          popcountp++;

        }

      *dstp++ = tmp;

    }

#ifdef BITMAP_DEBUGGING

  if (has_popcount)

    sbitmap_verify_popcount (dst);

#endif

}

/* Set DST to be (A or B)).

   Return nonzero if any change is made.  */

bool

sbitmap_a_or_b_cg (sbitmap dst, const_sbitmap a, const_sbitmap b)

{

  unsigned int i, n = dst->size;

  sbitmap_ptr dstp = dst->elms;

  const_sbitmap_ptr ap = a->elms;

  const_sbitmap_ptr bp = b->elms;

  SBITMAP_ELT_TYPE changed = 0;

  gcc_assert (!dst->popcount);

  for (i = 0; i < n; i++)

    {

      const SBITMAP_ELT_TYPE tmp = *ap++ | *bp++;

      changed |= *dstp ^ tmp;

      *dstp++ = tmp;

    }

  return changed != 0;

}

void

sbitmap_a_or_b (sbitmap dst, const_sbitmap a, const_sbitmap b)

{

  unsigned int i, n = dst->size;

  sbitmap_ptr dstp = dst->elms;

  const_sbitmap_ptr ap = a->elms;

  const_sbitmap_ptr bp = b->elms;

  bool has_popcount = dst->popcount != NULL;

  unsigned char *popcountp = dst->popcount;

  for (i = 0; i < n; i++)

    {

      const SBITMAP_ELT_TYPE tmp = *ap++ | *bp++;

      if (has_popcount)

        {

          bool wordchanged = (*dstp ^ tmp) != 0;

          if (wordchanged)

            *popcountp = do_popcount (tmp);

          popcountp++;

        }

      *dstp++ = tmp;

    }

#ifdef BITMAP_DEBUGGING

  if (has_popcount)

    sbitmap_verify_popcount (dst);

#endif

}

/* Return nonzero if A is a subset of B.  */

bool

sbitmap_a_subset_b_p (const_sbitmap a, const_sbitmap b)

{

  unsigned int i, n = a->size;

  const_sbitmap_ptr ap, bp;

  for (ap = a->elms, bp = b->elms, i = 0; i < n; i++, ap++, bp++)

    if ((*ap | *bp) != *bp)

      return false;

  return true;

}

/* Set DST to be (A or (B and C)).

   Return nonzero if any change is made.  */

bool

sbitmap_a_or_b_and_c_cg (sbitmap dst, const_sbitmap a, const_sbitmap b, const_sbitmap c)

{

  unsigned int i, n = dst->size;

  sbitmap_ptr dstp = dst->elms;

  const_sbitmap_ptr ap = a->elms;

  const_sbitmap_ptr bp = b->elms;

  const_sbitmap_ptr cp = c->elms;