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/* Code for range operators.
Copyright (C) 2017-2024 Free Software Foundation, Inc.
Contributed by Andrew MacLeod <amacleod@redhat.com>
and 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/>. */
#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "backend.h"
#include "insn-codes.h"
#include "rtl.h"
#include "tree.h"
#include "gimple.h"
#include "cfghooks.h"
#include "tree-pass.h"
#include "ssa.h"
#include "optabs-tree.h"
#include "gimple-pretty-print.h"
#include "diagnostic-core.h"
#include "flags.h"
#include "fold-const.h"
#include "stor-layout.h"
#include "calls.h"
#include "cfganal.h"
#include "gimple-iterator.h"
#include "gimple-fold.h"
#include "tree-eh.h"
#include "gimple-walk.h"
#include "tree-cfg.h"
#include "wide-int.h"
#include "value-relation.h"
#include "range-op.h"
#include "tree-ssa-ccp.h"
#include "range-op-mixed.h"
bool
range_operator::fold_range (prange &, tree, const prange &, const prange &,
relation_trio) const
{
return false;
}
bool
range_operator::fold_range (prange &, tree, const prange &, const irange &,
relation_trio) const
{
return false;
}
bool
range_operator::fold_range (irange &, tree, const prange &, const prange &,
relation_trio) const
{
return false;
}
bool
range_operator::fold_range (prange &, tree, const irange &, const prange &,
relation_trio) const
{
return false;
}
bool
range_operator::fold_range (irange &, tree, const prange &, const irange &,
relation_trio) const
{
return false;
}
bool
range_operator::op1_op2_relation_effect (prange &, tree,
const prange &,
const prange &,
relation_kind) const
{
return false;
}
bool
range_operator::op1_op2_relation_effect (prange &, tree,
const prange &,
const irange &,
relation_kind) const
{
return false;
}
bool
range_operator::op1_op2_relation_effect (irange &, tree,
const prange &,
const prange &,
relation_kind) const
{
return false;
}
bool
range_operator::op1_op2_relation_effect (prange &, tree,
const irange &,
const prange &,
relation_kind) const
{
return false;
}
bool
range_operator::op1_op2_relation_effect (irange &, tree,
const prange &,
const irange &,
relation_kind) const
{
return false;
}
bool
range_operator::op1_range (prange &, tree,
const prange &lhs ATTRIBUTE_UNUSED,
const prange &op2 ATTRIBUTE_UNUSED,
relation_trio) const
{
return false;
}
bool
range_operator::op1_range (prange &, tree,
const irange &lhs ATTRIBUTE_UNUSED,
const prange &op2 ATTRIBUTE_UNUSED,
relation_trio) const
{
return false;
}
bool
range_operator::op1_range (prange &, tree,
const prange &lhs ATTRIBUTE_UNUSED,
const irange &op2 ATTRIBUTE_UNUSED,
relation_trio) const
{
return false;
}
bool
range_operator::op1_range (irange &, tree,
const prange &lhs ATTRIBUTE_UNUSED,
const irange &op2 ATTRIBUTE_UNUSED,
relation_trio) const
{
return false;
}
bool
range_operator::op2_range (prange &, tree,
const irange &lhs ATTRIBUTE_UNUSED,
const prange &op1 ATTRIBUTE_UNUSED,
relation_trio) const
{
return false;
}
bool
range_operator::op2_range (irange &, tree,
const prange &lhs ATTRIBUTE_UNUSED,
const prange &op1 ATTRIBUTE_UNUSED,
relation_trio) const
{
return false;
}
relation_kind
range_operator::op1_op2_relation (const irange &lhs ATTRIBUTE_UNUSED,
const prange &op1 ATTRIBUTE_UNUSED,
const prange &op2 ATTRIBUTE_UNUSED) const
{
return VREL_VARYING;
}
relation_kind
range_operator::lhs_op1_relation (const prange &lhs ATTRIBUTE_UNUSED,
const irange &op1 ATTRIBUTE_UNUSED,
const irange &op2 ATTRIBUTE_UNUSED,
relation_kind rel ATTRIBUTE_UNUSED) const
{
return VREL_VARYING;
}
relation_kind
range_operator::lhs_op1_relation (const irange &lhs ATTRIBUTE_UNUSED,
const prange &op1 ATTRIBUTE_UNUSED,
const prange &op2 ATTRIBUTE_UNUSED,
relation_kind rel ATTRIBUTE_UNUSED) const
{
return VREL_VARYING;
}
relation_kind
range_operator::lhs_op1_relation (const prange &lhs ATTRIBUTE_UNUSED,
const prange &op1 ATTRIBUTE_UNUSED,
const prange &op2 ATTRIBUTE_UNUSED,
relation_kind rel ATTRIBUTE_UNUSED) const
{
return VREL_VARYING;
}
void
range_operator::update_bitmask (irange &,
const prange &,
const prange &) const
{
}
// Return the upper limit for a type.
static inline wide_int
max_limit (const_tree type)
{
return wi::max_value (TYPE_PRECISION (type), TYPE_SIGN (type));
}
// Return the lower limit for a type.
static inline wide_int
min_limit (const_tree type)
{
return wi::min_value (TYPE_PRECISION (type), TYPE_SIGN (type));
}
// Build a range that is < VAL and store it in R.
static void
build_lt (prange &r, tree type, const prange &val)
{
wi::overflow_type ov;
wide_int lim = wi::sub (val.upper_bound (), 1, UNSIGNED, &ov);
// If val - 1 underflows, check if X < MIN, which is an empty range.
if (ov)
r.set_undefined ();
else
r.set (type, min_limit (type), lim);
}
// Build a range that is <= VAL and store it in R.
static void
build_le (prange &r, tree type, const prange &val)
{
r.set (type, min_limit (type), val.upper_bound ());
}
// Build a range that is > VAL and store it in R.
static void
build_gt (prange &r, tree type, const prange &val)
{
wi::overflow_type ov;
wide_int lim = wi::add (val.lower_bound (), 1, UNSIGNED, &ov);
// If val + 1 overflows, check is for X > MAX, which is an empty range.
if (ov)
r.set_undefined ();
else
r.set (type, lim, max_limit (type));
}
// Build a range that is >= VAL and store it in R.
static void
build_ge (prange &r, tree type, const prange &val)
{
r.set (type, val.lower_bound (), max_limit (type));
}
class pointer_plus_operator : public range_operator
{
using range_operator::update_bitmask;
using range_operator::fold_range;
using range_operator::op2_range;
public:
virtual bool fold_range (prange &r, tree type,
const prange &op1,
const irange &op2,
relation_trio) const final override;
virtual bool op2_range (irange &r, tree type,
const prange &lhs,
const prange &op1,
relation_trio = TRIO_VARYING) const final override;
virtual void wi_fold (irange &r, tree type,
const wide_int &lh_lb,
const wide_int &lh_ub,
const wide_int &rh_lb,
const wide_int &rh_ub) const;
virtual bool op2_range (irange &r, tree type,
const irange &lhs,
const irange &op1,
relation_trio = TRIO_VARYING) const;
void update_bitmask (irange &r, const irange &lh, const irange &rh) const
{ update_known_bitmask (r, POINTER_PLUS_EXPR, lh, rh); }
} op_pointer_plus;
bool
pointer_plus_operator::fold_range (prange &r, tree type,
const prange &op1,
const irange &op2,
relation_trio) const
{
if (empty_range_varying (r, type, op1, op2))
return true;
const wide_int lh_lb = op1.lower_bound ();
const wide_int lh_ub = op1.upper_bound ();
const wide_int rh_lb = op2.lower_bound ();
const wide_int rh_ub = op2.upper_bound ();
// Check for [0,0] + const, and simply return the const.
if (lh_lb == 0 && lh_ub == 0 && rh_lb == rh_ub)
{
r.set (type, rh_lb, rh_lb);
return true;
}
// For pointer types, we are really only interested in asserting
// whether the expression evaluates to non-NULL.
//
// With -fno-delete-null-pointer-checks we need to be more
// conservative. As some object might reside at address 0,
// then some offset could be added to it and the same offset
// subtracted again and the result would be NULL.
// E.g.
// static int a[12]; where &a[0] is NULL and
// ptr = &a[6];
// ptr -= 6;
// ptr will be NULL here, even when there is POINTER_PLUS_EXPR
// where the first range doesn't include zero and the second one
// doesn't either. As the second operand is sizetype (unsigned),
// consider all ranges where the MSB could be set as possible
// subtractions where the result might be NULL.
if ((!wi_includes_zero_p (type, lh_lb, lh_ub)
|| !wi_includes_zero_p (type, rh_lb, rh_ub))
&& !TYPE_OVERFLOW_WRAPS (type)
&& (flag_delete_null_pointer_checks
|| !wi::sign_mask (rh_ub)))
r.set_nonzero (type);
else if (lh_lb == lh_ub && lh_lb == 0
&& rh_lb == rh_ub && rh_lb == 0)
r.set_zero (type);
else
r.set_varying (type);
update_known_bitmask (r, POINTER_PLUS_EXPR, op1, op2);
return true;
}
bool
pointer_plus_operator::op2_range (irange &r, tree type,
const prange &lhs ATTRIBUTE_UNUSED,
const prange &op1 ATTRIBUTE_UNUSED,
relation_trio trio) const
{
relation_kind rel = trio.lhs_op1 ();
r.set_varying (type);
// If the LHS and OP1 are equal, the op2 must be zero.
if (rel == VREL_EQ)
r.set_zero (type);
// If the LHS and OP1 are not equal, the offset must be non-zero.
else if (rel == VREL_NE)
r.set_nonzero (type);
else
return false;
return true;
}
void
pointer_plus_operator::wi_fold (irange &r, tree type,
const wide_int &lh_lb,
const wide_int &lh_ub,
const wide_int &rh_lb,
const wide_int &rh_ub) const
{
// Check for [0,0] + const, and simply return the const.
if (lh_lb == 0 && lh_ub == 0 && rh_lb == rh_ub)
{
r.set (type, rh_lb, rh_lb);
return;
}
// For pointer types, we are really only interested in asserting
// whether the expression evaluates to non-NULL.
//
// With -fno-delete-null-pointer-checks we need to be more
// conservative. As some object might reside at address 0,
// then some offset could be added to it and the same offset
// subtracted again and the result would be NULL.
// E.g.
// static int a[12]; where &a[0] is NULL and
// ptr = &a[6];
// ptr -= 6;
// ptr will be NULL here, even when there is POINTER_PLUS_EXPR
// where the first range doesn't include zero and the second one
// doesn't either. As the second operand is sizetype (unsigned),
// consider all ranges where the MSB could be set as possible
// subtractions where the result might be NULL.
if ((!wi_includes_zero_p (type, lh_lb, lh_ub)
|| !wi_includes_zero_p (type, rh_lb, rh_ub))
&& !TYPE_OVERFLOW_WRAPS (type)
&& (flag_delete_null_pointer_checks
|| !wi::sign_mask (rh_ub)))
r.set_nonzero (type);
else if (lh_lb == lh_ub && lh_lb == 0
&& rh_lb == rh_ub && rh_lb == 0)
r.set_zero (type);
else
r.set_varying (type);
}
bool
pointer_plus_operator::op2_range (irange &r, tree type,
const irange &lhs ATTRIBUTE_UNUSED,
const irange &op1 ATTRIBUTE_UNUSED,
relation_trio trio) const
{
relation_kind rel = trio.lhs_op1 ();
r.set_varying (type);
// If the LHS and OP1 are equal, the op2 must be zero.
if (rel == VREL_EQ)
r.set_zero (type);
// If the LHS and OP1 are not equal, the offset must be non-zero.
else if (rel == VREL_NE)
r.set_nonzero (type);
else
return false;
return true;
}
class pointer_min_max_operator : public range_operator
{
public:
virtual void wi_fold (irange & r, tree type,
const wide_int &lh_lb, const wide_int &lh_ub,
const wide_int &rh_lb, const wide_int &rh_ub) const;
} op_ptr_min_max;
void
pointer_min_max_operator::wi_fold (irange &r, tree type,
const wide_int &lh_lb,
const wide_int &lh_ub,
const wide_int &rh_lb,
const wide_int &rh_ub) const
{
// For MIN/MAX expressions with pointers, we only care about
// nullness. If both are non null, then the result is nonnull.
// If both are null, then the result is null. Otherwise they
// are varying.
if (!wi_includes_zero_p (type, lh_lb, lh_ub)
&& !wi_includes_zero_p (type, rh_lb, rh_ub))
r.set_nonzero (type);
else if (wi_zero_p (type, lh_lb, lh_ub) && wi_zero_p (type, rh_lb, rh_ub))
r.set_zero (type);
else
r.set_varying (type);
}
class pointer_and_operator : public range_operator
{
public:
virtual void wi_fold (irange &r, tree type,
const wide_int &lh_lb, const wide_int &lh_ub,
const wide_int &rh_lb, const wide_int &rh_ub) const;
} op_pointer_and;
void
pointer_and_operator::wi_fold (irange &r, tree type,
const wide_int &lh_lb,
const wide_int &lh_ub,
const wide_int &rh_lb ATTRIBUTE_UNUSED,
const wide_int &rh_ub ATTRIBUTE_UNUSED) const
{
// For pointer types, we are really only interested in asserting
// whether the expression evaluates to non-NULL.
if (wi_zero_p (type, lh_lb, lh_ub) || wi_zero_p (type, lh_lb, lh_ub))
r.set_zero (type);
else
r.set_varying (type);
}
class pointer_or_operator : public range_operator
{
public:
using range_operator::op1_range;
using range_operator::op2_range;
virtual bool op1_range (irange &r, tree type,
const irange &lhs,
const irange &op2,
relation_trio rel = TRIO_VARYING) const;
virtual bool op2_range (irange &r, tree type,
const irange &lhs,
const irange &op1,
relation_trio rel = TRIO_VARYING) const;
virtual void wi_fold (irange &r, tree type,
const wide_int &lh_lb, const wide_int &lh_ub,
const wide_int &rh_lb, const wide_int &rh_ub) const;
} op_pointer_or;
bool
pointer_or_operator::op1_range (irange &r, tree type,
const irange &lhs,
const irange &op2 ATTRIBUTE_UNUSED,
relation_trio) const
{
if (lhs.undefined_p ())
return false;
if (lhs.zero_p ())
{
r.set_zero (type);
return true;
}
r.set_varying (type);
return true;
}
bool
pointer_or_operator::op2_range (irange &r, tree type,
const irange &lhs,
const irange &op1,
relation_trio) const
{
return pointer_or_operator::op1_range (r, type, lhs, op1);
}
void
pointer_or_operator::wi_fold (irange &r, tree type,
const wide_int &lh_lb,
const wide_int &lh_ub,
const wide_int &rh_lb,
const wide_int &rh_ub) const
{
// For pointer types, we are really only interested in asserting
// whether the expression evaluates to non-NULL.
if (!wi_includes_zero_p (type, lh_lb, lh_ub)
&& !wi_includes_zero_p (type, rh_lb, rh_ub))
r.set_nonzero (type);
else if (wi_zero_p (type, lh_lb, lh_ub) && wi_zero_p (type, rh_lb, rh_ub))
r.set_zero (type);
else
r.set_varying (type);
}
class operator_pointer_diff : public range_operator
{
using range_operator::update_bitmask;
using range_operator::op1_op2_relation_effect;
virtual bool op1_op2_relation_effect (irange &lhs_range,
tree type,
const irange &op1_range,
const irange &op2_range,
relation_kind rel) const;
virtual bool op1_op2_relation_effect (irange &lhs_range,
tree type,
const prange &op1_range,
const prange &op2_range,
relation_kind rel) const final override;
void update_bitmask (irange &r, const irange &lh, const irange &rh) const
{ update_known_bitmask (r, POINTER_DIFF_EXPR, lh, rh); }
void update_bitmask (irange &r,
const prange &lh, const prange &rh) const final override
{ update_known_bitmask (r, POINTER_DIFF_EXPR, lh, rh); }
} op_pointer_diff;
bool
operator_pointer_diff::op1_op2_relation_effect (irange &lhs_range, tree type,
const prange &op1_range,
const prange &op2_range,
relation_kind rel) const
{
int_range<2> op1, op2, tmp;
range_op_handler cast (CONVERT_EXPR);
if (!cast.fold_range (op1, type, op1_range, tmp)
|| !cast.fold_range (op2, type, op2_range, tmp))
return false;
return minus_op1_op2_relation_effect (lhs_range, type, op1, op2, rel);
}
bool
operator_pointer_diff::op1_op2_relation_effect (irange &lhs_range, tree type,
const irange &op1_range,
const irange &op2_range,
relation_kind rel) const
{
return minus_op1_op2_relation_effect (lhs_range, type, op1_range, op2_range,
rel);
}
bool
operator_identity::fold_range (prange &r, tree type ATTRIBUTE_UNUSED,
const prange &lh ATTRIBUTE_UNUSED,
const prange &rh ATTRIBUTE_UNUSED,
relation_trio) const
{
r = lh;
return true;
}
relation_kind
operator_identity::lhs_op1_relation (const prange &lhs,
const prange &op1 ATTRIBUTE_UNUSED,
const prange &op2 ATTRIBUTE_UNUSED,
relation_kind) const
{
if (lhs.undefined_p ())
return VREL_VARYING;
// Simply a copy, so they are equivalent.
return VREL_EQ;
}
bool
operator_identity::op1_range (prange &r, tree type ATTRIBUTE_UNUSED,
const prange &lhs,
const prange &op2 ATTRIBUTE_UNUSED,
relation_trio) const
{
r = lhs;
return true;
}
bool
operator_cst::fold_range (prange &r, tree type ATTRIBUTE_UNUSED,
const prange &lh,
const prange & ATTRIBUTE_UNUSED,
relation_trio) const
{
r = lh;
return true;
}
// Cast between pointers.
bool
operator_cast::fold_range (prange &r, tree type,
const prange &inner,
const prange &outer,
relation_trio) const
{
if (empty_range_varying (r, type, inner, outer))
return true;
r.set (type, inner.lower_bound (), inner.upper_bound ());
r.update_bitmask (inner.get_bitmask ());
return true;
}
// Cast a pointer to an integer.
bool
operator_cast::fold_range (irange &r, tree type,
const prange &inner,
const irange &outer,
relation_trio) const
{
if (empty_range_varying (r, type, inner, outer))
return true;
// Represent INNER as an integer of the same size, and then cast it
// to the resulting integer type.
tree pointer_uint_type = make_unsigned_type (TYPE_PRECISION (inner.type ()));
r.set (pointer_uint_type, inner.lower_bound (), inner.upper_bound ());
r.update_bitmask (inner.get_bitmask ());
range_cast (r, type);
return true;
}
// Cast an integer to a pointer.
bool
operator_cast::fold_range (prange &r, tree type,
const irange &inner,
const prange &outer,
relation_trio) const
{
if (empty_range_varying (r, type, inner, outer))
return true;
// Cast INNER to an integer of the same size as the pointer we want,
// and then copy the bounds to the resulting pointer range.
int_range<2> tmp = inner;
tree pointer_uint_type = make_unsigned_type (TYPE_PRECISION (type));
range_cast (tmp, pointer_uint_type);
r.set (type, tmp.lower_bound (), tmp.upper_bound ());
r.update_bitmask (tmp.get_bitmask ());
return true;
}
bool
operator_cast::op1_range (prange &r, tree type,
const prange &lhs,
const prange &op2,
relation_trio trio) const
{
if (lhs.undefined_p ())
return false;
gcc_checking_assert (types_compatible_p (op2.type(), type));
// Conversion from other pointers or a constant (including 0/NULL)
// are straightforward.
if (POINTER_TYPE_P (lhs.type ())
|| (lhs.singleton_p ()
&& TYPE_PRECISION (lhs.type ()) >= TYPE_PRECISION (type)))
fold_range (r, type, lhs, op2, trio);
else
{
// If the LHS is not a pointer nor a singleton, then it is
// either VARYING or non-zero.
if (!lhs.undefined_p () && !range_includes_zero_p (lhs))
r.set_nonzero (type);
else
r.set_varying (type);
}
r.intersect (op2);
return true;
}
bool
operator_cast::op1_range (irange &r, tree type,
const prange &lhs,
const irange &op2,
relation_trio trio) const
{
if (lhs.undefined_p ())
return false;
gcc_checking_assert (types_compatible_p (op2.type(), type));
// Conversion from other pointers or a constant (including 0/NULL)
// are straightforward.
if (POINTER_TYPE_P (lhs.type ())
|| (lhs.singleton_p ()
&& TYPE_PRECISION (lhs.type ()) >= TYPE_PRECISION (type)))
fold_range (r, type, lhs, op2, trio);
else
{
// If the LHS is not a pointer nor a singleton, then it is
// either VARYING or non-zero.
if (!lhs.undefined_p () && !range_includes_zero_p (lhs))
r.set_nonzero (type);
else
r.set_varying (type);
}
r.intersect (op2);
return true;
}
bool
operator_cast::op1_range (prange &r, tree type,
const irange &lhs,
const prange &op2,
relation_trio trio) const
{
if (lhs.undefined_p ())
return false;
gcc_checking_assert (types_compatible_p (op2.type(), type));
// Conversion from other pointers or a constant (including 0/NULL)
// are straightforward.
if (POINTER_TYPE_P (lhs.type ())
|| (lhs.singleton_p ()
&& TYPE_PRECISION (lhs.type ()) >= TYPE_PRECISION (type)))
fold_range (r, type, lhs, op2, trio);
else
{
// If the LHS is not a pointer nor a singleton, then it is
// either VARYING or non-zero.
if (!lhs.undefined_p () && !range_includes_zero_p (lhs))
r.set_nonzero (type);
else
r.set_varying (type);
}
r.intersect (op2);
return true;
}
relation_kind
operator_cast::lhs_op1_relation (const prange &lhs,
const prange &op1,
const prange &op2 ATTRIBUTE_UNUSED,
relation_kind) const
{
if (lhs.undefined_p () || op1.undefined_p ())
return VREL_VARYING;
unsigned lhs_prec = TYPE_PRECISION (lhs.type ());
unsigned op1_prec = TYPE_PRECISION (op1.type ());
// If the result gets sign extended into a larger type check first if this
// qualifies as a partial equivalence.
if (TYPE_SIGN (op1.type ()) == SIGNED && lhs_prec > op1_prec)
{
// If the result is sign extended, and the LHS is larger than op1,
// check if op1's range can be negative as the sign extension will
// cause the upper bits to be 1 instead of 0, invalidating the PE.
int_range<3> negs = range_negatives (op1.type ());
negs.intersect (op1);
if (!negs.undefined_p ())
return VREL_VARYING;
}
unsigned prec = MIN (lhs_prec, op1_prec);
return bits_to_pe (prec);
}
relation_kind
operator_cast::lhs_op1_relation (const prange &lhs,
const irange &op1,
const irange &op2 ATTRIBUTE_UNUSED,
relation_kind) const
{
if (lhs.undefined_p () || op1.undefined_p ())
return VREL_VARYING;
unsigned lhs_prec = TYPE_PRECISION (lhs.type ());
unsigned op1_prec = TYPE_PRECISION (op1.type ());
// If the result gets sign extended into a larger type check first if this
// qualifies as a partial equivalence.
if (TYPE_SIGN (op1.type ()) == SIGNED && lhs_prec > op1_prec)
{
// If the result is sign extended, and the LHS is larger than op1,
// check if op1's range can be negative as the sign extension will
// cause the upper bits to be 1 instead of 0, invalidating the PE.
int_range<3> negs = range_negatives (op1.type ());
negs.intersect (op1);
if (!negs.undefined_p ())
return VREL_VARYING;
}
unsigned prec = MIN (lhs_prec, op1_prec);
return bits_to_pe (prec);
}
relation_kind
operator_cast::lhs_op1_relation (const irange &lhs,
const prange &op1,
const prange &op2 ATTRIBUTE_UNUSED,
relation_kind) const
{
if (lhs.undefined_p () || op1.undefined_p ())
return VREL_VARYING;
unsigned lhs_prec = TYPE_PRECISION (lhs.type ());
unsigned op1_prec = TYPE_PRECISION (op1.type ());
// If the result gets sign extended into a larger type check first if this
// qualifies as a partial equivalence.
if (TYPE_SIGN (op1.type ()) == SIGNED && lhs_prec > op1_prec)
{
// If the result is sign extended, and the LHS is larger than op1,
// check if op1's range can be negative as the sign extension will
// cause the upper bits to be 1 instead of 0, invalidating the PE.
int_range<3> negs = range_negatives (op1.type ());
negs.intersect (op1);
if (!negs.undefined_p ())
return VREL_VARYING;
}
unsigned prec = MIN (lhs_prec, op1_prec);
return bits_to_pe (prec);
}
bool
operator_min::fold_range (prange &r, tree type,
const prange &op1,
const prange &op2,
relation_trio) const
{
// For MIN/MAX expressions with pointers, we only care about
// nullness. If both are non null, then the result is nonnull.
// If both are null, then the result is null. Otherwise they
// are varying.
if (!range_includes_zero_p (op1)
&& !range_includes_zero_p (op2))
r.set_nonzero (type);
else if (op1.zero_p () && op2.zero_p ())
r.set_zero (type);
else
r.set_varying (type);
update_known_bitmask (r, MIN_EXPR, op1, op2);
return true;
}
bool
operator_max::fold_range (prange &r, tree type,
const prange &op1,
const prange &op2,
relation_trio) const
{
// For MIN/MAX expressions with pointers, we only care about
// nullness. If both are non null, then the result is nonnull.
// If both are null, then the result is null. Otherwise they
// are varying.
if (!range_includes_zero_p (op1)
&& !range_includes_zero_p (op2))
r.set_nonzero (type);
else if (op1.zero_p () && op2.zero_p ())
r.set_zero (type);
else
r.set_varying (type);
update_known_bitmask (r, MAX_EXPR, op1, op2);
return true;
}
bool
operator_addr_expr::op1_range (prange &r, tree type,
const prange &lhs,
const prange &op2,
relation_trio) const
{
if (empty_range_varying (r, type, lhs, op2))
return true;
// Return a non-null pointer of the LHS type (passed in op2), but only
// if we cant overflow, eitherwise a no-zero offset could wrap to zero.
// See PR 111009.
if (!lhs.undefined_p ()
&& !range_includes_zero_p (lhs)
&& TYPE_OVERFLOW_UNDEFINED (type))
r.set_nonzero (type);
else
r.set_varying (type);
return true;
}
bool
operator_bitwise_and::fold_range (prange &r, tree type,
const prange &op1,
const prange &op2 ATTRIBUTE_UNUSED,
relation_trio) const
{
// For pointer types, we are really only interested in asserting
// whether the expression evaluates to non-NULL.
if (op1.zero_p () || op2.zero_p ())
r.set_zero (type);
else
r.set_varying (type);
update_known_bitmask (r, BIT_AND_EXPR, op1, op2);
return true;
}
bool
operator_equal::fold_range (irange &r, tree type,
const prange &op1,
const prange &op2,
relation_trio rel) const
{
if (relop_early_resolve (r, type, op1, op2, rel, VREL_EQ))
return true;
// We can be sure the values are always equal or not if both ranges
// consist of a single value, and then compare them.
bool op1_const = wi::eq_p (op1.lower_bound (), op1.upper_bound ());
bool op2_const = wi::eq_p (op2.lower_bound (), op2.upper_bound ());
if (op1_const && op2_const)
{
if (wi::eq_p (op1.lower_bound (), op2.upper_bound()))
r = range_true ();
else
r = range_false ();
}
else
{
// If ranges do not intersect, we know the range is not equal,
// otherwise we don't know anything for sure.
prange tmp = op1;
tmp.intersect (op2);
if (tmp.undefined_p ())
r = range_false ();
// Check if a constant cannot satisfy the bitmask requirements.
else if (op2_const && !op1.get_bitmask ().member_p (op2.lower_bound ()))
r = range_false ();
else if (op1_const && !op2.get_bitmask ().member_p (op1.lower_bound ()))
r = range_false ();
else
r = range_true_and_false ();
}
//update_known_bitmask (r, EQ_EXPR, op1, op2);
return true;
}
bool
operator_equal::op1_range (prange &r, tree type,
const irange &lhs,
const prange &op2,
relation_trio) const
{
switch (get_bool_state (r, lhs, type))
{
case BRS_TRUE:
// If it's true, the result is the same as OP2.
r = op2;
break;
case BRS_FALSE:
// If the result is false, the only time we know anything is
// if OP2 is a constant.
if (!op2.undefined_p ()
&& wi::eq_p (op2.lower_bound(), op2.upper_bound()))
{
r = op2;
r.invert ();
}
else
r.set_varying (type);
break;
default:
break;
}
return true;
}
bool
operator_equal::op2_range (prange &r, tree type,
const irange &lhs,
const prange &op1,
relation_trio rel) const
{
return operator_equal::op1_range (r, type, lhs, op1, rel.swap_op1_op2 ());
}
relation_kind
operator_equal::op1_op2_relation (const irange &lhs, const prange &,
const prange &) const
{
if (lhs.undefined_p ())
return VREL_UNDEFINED;
// FALSE = op1 == op2 indicates NE_EXPR.
if (lhs.zero_p ())
return VREL_NE;
// TRUE = op1 == op2 indicates EQ_EXPR.
if (!range_includes_zero_p (lhs))
return VREL_EQ;
return VREL_VARYING;
}
bool
operator_not_equal::fold_range (irange &r, tree type,
const prange &op1,
const prange &op2,
relation_trio rel) const
{
if (relop_early_resolve (r, type, op1, op2, rel, VREL_NE))
return true;
// We can be sure the values are always equal or not if both ranges
// consist of a single value, and then compare them.
bool op1_const = wi::eq_p (op1.lower_bound (), op1.upper_bound ());
bool op2_const = wi::eq_p (op2.lower_bound (), op2.upper_bound ());
if (op1_const && op2_const)
{
if (wi::ne_p (op1.lower_bound (), op2.upper_bound()))
r = range_true ();
else
r = range_false ();
}
else
{
// If ranges do not intersect, we know the range is not equal,
// otherwise we don't know anything for sure.
prange tmp = op1;
tmp.intersect (op2);
if (tmp.undefined_p ())
r = range_true ();
// Check if a constant cannot satisfy the bitmask requirements.
else if (op2_const && !op1.get_bitmask ().member_p (op2.lower_bound ()))
r = range_true ();
else if (op1_const && !op2.get_bitmask ().member_p (op1.lower_bound ()))
r = range_true ();
else
r = range_true_and_false ();
}
//update_known_bitmask (r, NE_EXPR, op1, op2);
return true;
}
bool
operator_not_equal::op1_range (prange &r, tree type,
const irange &lhs,
const prange &op2,
relation_trio) const
{
switch (get_bool_state (r, lhs, type))
{
case BRS_TRUE:
// If the result is true, the only time we know anything is if
// OP2 is a constant.
if (!op2.undefined_p ()
&& wi::eq_p (op2.lower_bound(), op2.upper_bound()))
{
r = op2;
r.invert ();
}
else
r.set_varying (type);
break;
case BRS_FALSE:
// If it's false, the result is the same as OP2.
r = op2;
break;
default:
break;
}
return true;
}
bool
operator_not_equal::op2_range (prange &r, tree type,
const irange &lhs,
const prange &op1,
relation_trio rel) const
{
return operator_not_equal::op1_range (r, type, lhs, op1, rel.swap_op1_op2 ());
}
relation_kind
operator_not_equal::op1_op2_relation (const irange &lhs, const prange &,
const prange &) const
{
if (lhs.undefined_p ())
return VREL_UNDEFINED;
// FALSE = op1 != op2 indicates EQ_EXPR.
if (lhs.zero_p ())
return VREL_EQ;
// TRUE = op1 != op2 indicates NE_EXPR.
if (!range_includes_zero_p (lhs))
return VREL_NE;
return VREL_VARYING;
}
bool
operator_lt::fold_range (irange &r, tree type,
const prange &op1,
const prange &op2,
relation_trio rel) const
{
if (relop_early_resolve (r, type, op1, op2, rel, VREL_LT))
return true;
signop sign = TYPE_SIGN (op1.type ());
gcc_checking_assert (sign == TYPE_SIGN (op2.type ()));
if (wi::lt_p (op1.upper_bound (), op2.lower_bound (), sign))
r = range_true ();
else if (!wi::lt_p (op1.lower_bound (), op2.upper_bound (), sign))
r = range_false ();
// Use nonzero bits to determine if < 0 is false.
else if (op2.zero_p () && !wi::neg_p (op1.get_nonzero_bits (), sign))
r = range_false ();
else
r = range_true_and_false ();
//update_known_bitmask (r, LT_EXPR, op1, op2);
return true;
}
bool
operator_lt::op1_range (prange &r, tree type,
const irange &lhs,
const prange &op2,
relation_trio) const
{
if (op2.undefined_p ())
return false;
switch (get_bool_state (r, lhs, type))
{
case BRS_TRUE:
build_lt (r, type, op2);
break;
case BRS_FALSE:
build_ge (r, type, op2);
break;
default:
break;
}
return true;
}
bool
operator_lt::op2_range (prange &r, tree type,
const irange &lhs,
const prange &op1,
relation_trio) const
{
if (op1.undefined_p ())
return false;
switch (get_bool_state (r, lhs, type))
{
case BRS_TRUE:
build_gt (r, type, op1);
break;
case BRS_FALSE:
build_le (r, type, op1);
break;
default:
break;
}
return true;
}
relation_kind
operator_lt::op1_op2_relation (const irange &lhs, const prange &,
const prange &) const
{
if (lhs.undefined_p ())
return VREL_UNDEFINED;
// FALSE = op1 < op2 indicates GE_EXPR.
if (lhs.zero_p ())
return VREL_GE;
// TRUE = op1 < op2 indicates LT_EXPR.
if (!range_includes_zero_p (lhs))
return VREL_LT;
return VREL_VARYING;
}
bool
operator_le::fold_range (irange &r, tree type,
const prange &op1,
const prange &op2,
relation_trio rel) const
{
if (relop_early_resolve (r, type, op1, op2, rel, VREL_LE))
return true;
signop sign = TYPE_SIGN (op1.type ());
gcc_checking_assert (sign == TYPE_SIGN (op2.type ()));
if (wi::le_p (op1.upper_bound (), op2.lower_bound (), sign))
r = range_true ();
else if (!wi::le_p (op1.lower_bound (), op2.upper_bound (), sign))
r = range_false ();
else
r = range_true_and_false ();
//update_known_bitmask (r, LE_EXPR, op1, op2);
return true;
}
bool
operator_le::op1_range (prange &r, tree type,
const irange &lhs,
const prange &op2,
relation_trio) const
{
if (op2.undefined_p ())
return false;
switch (get_bool_state (r, lhs, type))
{
case BRS_TRUE:
build_le (r, type, op2);
break;
case BRS_FALSE:
build_gt (r, type, op2);
break;
default:
break;
}
return true;
}
bool
operator_le::op2_range (prange &r, tree type,
const irange &lhs,
const prange &op1,
relation_trio) const
{
if (op1.undefined_p ())
return false;
switch (get_bool_state (r, lhs, type))
{
case BRS_TRUE:
build_ge (r, type, op1);
break;
case BRS_FALSE:
build_lt (r, type, op1);
break;
default:
break;
}
return true;
}
relation_kind
operator_le::op1_op2_relation (const irange &lhs, const prange &,
const prange &) const
{
if (lhs.undefined_p ())
return VREL_UNDEFINED;
// FALSE = op1 <= op2 indicates GT_EXPR.
if (lhs.zero_p ())
return VREL_GT;
// TRUE = op1 <= op2 indicates LE_EXPR.
if (!range_includes_zero_p (lhs))
return VREL_LE;
return VREL_VARYING;
}
bool
operator_gt::fold_range (irange &r, tree type,
const prange &op1, const prange &op2,
relation_trio rel) const
{
if (relop_early_resolve (r, type, op1, op2, rel, VREL_GT))
return true;
signop sign = TYPE_SIGN (op1.type ());
gcc_checking_assert (sign == TYPE_SIGN (op2.type ()));
if (wi::gt_p (op1.lower_bound (), op2.upper_bound (), sign))
r = range_true ();
else if (!wi::gt_p (op1.upper_bound (), op2.lower_bound (), sign))
r = range_false ();
else
r = range_true_and_false ();
//update_known_bitmask (r, GT_EXPR, op1, op2);
return true;
}
bool
operator_gt::op1_range (prange &r, tree type,
const irange &lhs, const prange &op2,
relation_trio) const
{
if (op2.undefined_p ())
return false;
switch (get_bool_state (r, lhs, type))
{
case BRS_TRUE:
build_gt (r, type, op2);
break;
case BRS_FALSE:
build_le (r, type, op2);
break;
default:
break;
}
return true;
}
bool
operator_gt::op2_range (prange &r, tree type,
const irange &lhs,
const prange &op1,
relation_trio) const
{
if (op1.undefined_p ())
return false;
switch (get_bool_state (r, lhs, type))
{
case BRS_TRUE:
build_lt (r, type, op1);
break;
case BRS_FALSE:
build_ge (r, type, op1);
break;
default:
break;
}
return true;
}
relation_kind
operator_gt::op1_op2_relation (const irange &lhs, const prange &,
const prange &) const
{
if (lhs.undefined_p ())
return VREL_UNDEFINED;
// FALSE = op1 > op2 indicates LE_EXPR.
if (lhs.zero_p ())
return VREL_LE;
// TRUE = op1 > op2 indicates GT_EXPR.
if (!range_includes_zero_p (lhs))
return VREL_GT;
return VREL_VARYING;
}
bool
operator_ge::fold_range (irange &r, tree type,
const prange &op1,
const prange &op2,
relation_trio rel) const
{
if (relop_early_resolve (r, type, op1, op2, rel, VREL_GE))
return true;
signop sign = TYPE_SIGN (op1.type ());
gcc_checking_assert (sign == TYPE_SIGN (op2.type ()));
if (wi::ge_p (op1.lower_bound (), op2.upper_bound (), sign))
r = range_true ();
else if (!wi::ge_p (op1.upper_bound (), op2.lower_bound (), sign))
r = range_false ();
else
r = range_true_and_false ();
//update_known_bitmask (r, GE_EXPR, op1, op2);
return true;
}
bool
operator_ge::op1_range (prange &r, tree type,
const irange &lhs,
const prange &op2,
relation_trio) const
{
if (op2.undefined_p ())
return false;
switch (get_bool_state (r, lhs, type))
{
case BRS_TRUE:
build_ge (r, type, op2);
break;
case BRS_FALSE:
build_lt (r, type, op2);
break;
default:
break;
}
return true;
}
bool
operator_ge::op2_range (prange &r, tree type,
const irange &lhs,
const prange &op1,
relation_trio) const
{
if (op1.undefined_p ())
return false;
switch (get_bool_state (r, lhs, type))
{
case BRS_TRUE:
build_le (r, type, op1);
break;
case BRS_FALSE:
build_gt (r, type, op1);
break;
default:
break;
}
return true;
}
relation_kind
operator_ge::op1_op2_relation (const irange &lhs, const prange &,
const prange &) const
{
if (lhs.undefined_p ())
return VREL_UNDEFINED;
// FALSE = op1 >= op2 indicates LT_EXPR.
if (lhs.zero_p ())
return VREL_LT;
// TRUE = op1 >= op2 indicates GE_EXPR.
if (!range_includes_zero_p (lhs))
return VREL_GE;
return VREL_VARYING;
}
// Initialize any pointer operators to the primary table
void
range_op_table::initialize_pointer_ops ()
{
set (POINTER_PLUS_EXPR, op_pointer_plus);
set (POINTER_DIFF_EXPR, op_pointer_diff);
}
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