geos/opt/lib/gcc/i686-elf/13.2.0/plugin/include/value-range-storage.h
2024-03-26 15:15:06 +01:00

234 lines
6.4 KiB
C++

/* Support routines for vrange storage.
Copyright (C) 2022-2023 Free Software Foundation, Inc.
Contributed by Aldy Hernandez <aldyh@redhat.com>.
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/>. */
#ifndef GCC_VALUE_RANGE_STORAGE_H
#define GCC_VALUE_RANGE_STORAGE_H
// This class is used to allocate the minimum amount of storage needed
// for a given range. Storage is automatically freed at destruction
// of the class.
class vrange_allocator
{
public:
vrange_allocator () { }
virtual ~vrange_allocator () { }
// Allocate a range of TYPE.
vrange *alloc_vrange (tree type);
// Allocate a memory block of BYTES.
virtual void *alloc (unsigned bytes) = 0;
virtual void free (void *p) = 0;
// Return a clone of SRC.
template <typename T> T *clone (const T &src);
private:
irange *alloc_irange (unsigned pairs);
frange *alloc_frange ();
void operator= (const vrange_allocator &) = delete;
};
// This class is used to allocate chunks of memory that can store
// ranges as memory efficiently as possible. It is meant to be used
// when long term storage of a range is needed. The class can be used
// with any vrange_allocator (i.e. alloca or GC).
class vrange_storage
{
public:
vrange_storage (vrange_allocator *alloc) : m_alloc (alloc) { }
void *alloc_slot (const vrange &r);
void free (void *slot) { m_alloc->free (slot); }
void get_vrange (const void *slot, vrange &r, tree type);
void set_vrange (void *slot, const vrange &r);
static bool fits_p (const void *slot, const vrange &r);
private:
DISABLE_COPY_AND_ASSIGN (vrange_storage);
vrange_allocator *m_alloc;
};
// A chunk of memory pointing to an irange storage.
class GTY ((variable_size)) irange_storage_slot
{
public:
static irange_storage_slot *alloc_slot (vrange_allocator &, const irange &r);
void set_irange (const irange &r);
void get_irange (irange &r, tree type) const;
wide_int get_nonzero_bits () const { return m_ints[0]; }
bool fits_p (const irange &r) const;
static size_t size (const irange &r);
void dump () const;
private:
DISABLE_COPY_AND_ASSIGN (irange_storage_slot);
friend void gt_ggc_mx_irange_storage_slot (void *);
friend void gt_pch_p_19irange_storage_slot (void *, void *,
gt_pointer_operator, void *);
friend void gt_pch_nx_irange_storage_slot (void *);
// This is the maximum number of wide_int's allowed in the trailing
// ints structure, without going over 16 bytes (128 bits) in the
// control word that precedes the HOST_WIDE_INTs in
// trailing_wide_ints::m_val[].
static const unsigned MAX_INTS = 12;
// Maximum number of range pairs we can handle, considering the
// nonzero bits take one wide_int.
static const unsigned MAX_PAIRS = (MAX_INTS - 1) / 2;
// Constructor is private to disallow stack initialization. Use
// alloc_slot() to create objects.
irange_storage_slot (const irange &r);
static unsigned num_wide_ints_needed (const irange &r);
trailing_wide_ints<MAX_INTS> m_ints;
};
// A chunk of memory to store an frange to long term memory.
class GTY (()) frange_storage_slot
{
public:
static frange_storage_slot *alloc_slot (vrange_allocator &, const frange &r);
void set_frange (const frange &r);
void get_frange (frange &r, tree type) const;
bool fits_p (const frange &) const;
private:
frange_storage_slot (const frange &r) { set_frange (r); }
DISABLE_COPY_AND_ASSIGN (frange_storage_slot);
enum value_range_kind m_kind;
REAL_VALUE_TYPE m_min;
REAL_VALUE_TYPE m_max;
bool m_pos_nan;
bool m_neg_nan;
};
class obstack_vrange_allocator final: public vrange_allocator
{
public:
obstack_vrange_allocator ()
{
obstack_init (&m_obstack);
}
virtual ~obstack_vrange_allocator () final override
{
obstack_free (&m_obstack, NULL);
}
virtual void *alloc (unsigned bytes) final override
{
return obstack_alloc (&m_obstack, bytes);
}
virtual void free (void *) final override { }
private:
obstack m_obstack;
};
class ggc_vrange_allocator final: public vrange_allocator
{
public:
ggc_vrange_allocator () { }
virtual ~ggc_vrange_allocator () final override { }
virtual void *alloc (unsigned bytes) final override
{
return ggc_internal_alloc (bytes);
}
virtual void free (void *p) final override
{
return ggc_free (p);
}
};
// Return a new range to hold ranges of TYPE. The newly allocated
// range is initialized to VR_UNDEFINED.
inline vrange *
vrange_allocator::alloc_vrange (tree type)
{
if (irange::supports_p (type))
return alloc_irange (2);
if (frange::supports_p (type))
return alloc_frange ();
return NULL;
gcc_unreachable ();
}
// Return a new range with NUM_PAIRS.
inline irange *
vrange_allocator::alloc_irange (unsigned num_pairs)
{
// Never allocate 0 pairs.
// Don't allocate 1 either, or we get legacy value_range's.
if (num_pairs < 2)
num_pairs = 2;
size_t nbytes = sizeof (tree) * 2 * num_pairs;
// Allocate the irange and required memory for the vector.
void *r = alloc (sizeof (irange));
tree *mem = static_cast <tree *> (alloc (nbytes));
return new (r) irange (mem, num_pairs);
}
inline frange *
vrange_allocator::alloc_frange ()
{
void *r = alloc (sizeof (frange));
return new (r) frange ();
}
// Return a clone of an irange.
template <>
inline irange *
vrange_allocator::clone <irange> (const irange &src)
{
irange *r = alloc_irange (src.num_pairs ());
*r = src;
return r;
}
// Return a clone of an frange.
template <>
inline frange *
vrange_allocator::clone <frange> (const frange &src)
{
frange *r = alloc_frange ();
*r = src;
return r;
}
// Return a clone of a vrange.
template <>
inline vrange *
vrange_allocator::clone <vrange> (const vrange &src)
{
if (is_a <irange> (src))
return clone <irange> (as_a <irange> (src));
if (is_a <frange> (src))
return clone <frange> (as_a <frange> (src));
return NULL;
gcc_unreachable ();
}
#endif // GCC_VALUE_RANGE_STORAGE_H