/* Fold a constant sub-tree into a single node for C-compiler
Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
- 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+ 2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
This file is part of GCC.
#include "langhooks.h"
#include "md5.h"
+/* Non-zero if we are folding constants inside an initializer; zero
+ otherwise. */
+int folding_initializer = 0;
+
/* The following constants represent a bit based encoding of GCC's
comparison operators. This encoding simplifies transformations
on relational comparison operators, such as AND and OR. */
static tree sign_bit_p (tree, tree);
static int simple_operand_p (tree);
static tree range_binop (enum tree_code, tree, tree, int, tree, int);
+static tree range_predecessor (tree);
+static tree range_successor (tree);
static tree make_range (tree, int *, tree *, tree *);
static tree build_range_check (tree, tree, int, tree, tree);
static int merge_ranges (int *, tree *, tree *, int, tree, tree, int, tree,
static tree fold_negate_const (tree, tree);
static tree fold_not_const (tree, tree);
static tree fold_relational_const (enum tree_code, tree, tree, tree);
+static int native_encode_expr (tree, unsigned char *, int);
+static tree native_interpret_expr (tree, unsigned char *, int);
+
/* We know that A1 + B1 = SUM1, using 2's complement arithmetic and ignoring
overflow. Suppose A, B and SUM have the same respective signs as A1, B1,
}
/* Determine whether an expression T can be cheaply negated using
- the function negate_expr. */
+ the function negate_expr without introducing undefined overflow. */
static bool
negate_expr_p (tree t)
switch (TREE_CODE (t))
{
case INTEGER_CST:
- if (TYPE_UNSIGNED (type) || ! flag_trapv)
+ if (TYPE_UNSIGNED (type)
+ || (flag_wrapv && ! flag_trapv))
return true;
/* Check that -CST will not overflow type. */
return may_negate_without_overflow_p (t);
case BIT_NOT_EXPR:
- return INTEGRAL_TYPE_P (type);
+ return INTEGRAL_TYPE_P (type)
+ && (TYPE_UNSIGNED (type)
+ || (flag_wrapv && !flag_trapv));
case REAL_CST:
case NEGATE_EXPR:
return false;
}
-/* Given T, an expression, return the negation of T. Allow for T to be
- null, in which case return null. */
+/* Given T, an expression, return a folded tree for -T or NULL_TREE, if no
+ simplification is possible.
+ If negate_expr_p would return true for T, NULL_TREE will never be
+ returned. */
static tree
-negate_expr (tree t)
+fold_negate_expr (tree t)
{
- tree type;
+ tree type = TREE_TYPE (t);
tree tem;
- if (t == 0)
- return 0;
-
- type = TREE_TYPE (t);
- STRIP_SIGN_NOPS (t);
-
switch (TREE_CODE (t))
{
/* Convert - (~A) to A + 1. */
tem = fold_negate_const (t, type);
/* Two's complement FP formats, such as c4x, may overflow. */
if (! TREE_OVERFLOW (tem) || ! flag_trapping_math)
- return fold_convert (type, tem);
+ return tem;
break;
case COMPLEX_CST:
break;
case NEGATE_EXPR:
- return fold_convert (type, TREE_OPERAND (t, 0));
+ return TREE_OPERAND (t, 0);
case PLUS_EXPR:
if (! FLOAT_TYPE_P (type) || flag_unsafe_math_optimizations)
TREE_OPERAND (t, 1)))
{
tem = negate_expr (TREE_OPERAND (t, 1));
- tem = fold_build2 (MINUS_EXPR, TREE_TYPE (t),
- tem, TREE_OPERAND (t, 0));
- return fold_convert (type, tem);
+ return fold_build2 (MINUS_EXPR, type,
+ tem, TREE_OPERAND (t, 0));
}
/* -(A + B) -> (-A) - B. */
if (negate_expr_p (TREE_OPERAND (t, 0)))
{
tem = negate_expr (TREE_OPERAND (t, 0));
- tem = fold_build2 (MINUS_EXPR, TREE_TYPE (t),
- tem, TREE_OPERAND (t, 1));
- return fold_convert (type, tem);
+ return fold_build2 (MINUS_EXPR, type,
+ tem, TREE_OPERAND (t, 1));
}
}
break;
/* - (A - B) -> B - A */
if ((! FLOAT_TYPE_P (type) || flag_unsafe_math_optimizations)
&& reorder_operands_p (TREE_OPERAND (t, 0), TREE_OPERAND (t, 1)))
- return fold_convert (type,
- fold_build2 (MINUS_EXPR, TREE_TYPE (t),
- TREE_OPERAND (t, 1),
- TREE_OPERAND (t, 0)));
+ return fold_build2 (MINUS_EXPR, type,
+ TREE_OPERAND (t, 1), TREE_OPERAND (t, 0));
break;
case MULT_EXPR:
- if (TYPE_UNSIGNED (TREE_TYPE (t)))
+ if (TYPE_UNSIGNED (type))
break;
/* Fall through. */
case RDIV_EXPR:
- if (! HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (TREE_TYPE (t))))
+ if (! HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type)))
{
tem = TREE_OPERAND (t, 1);
if (negate_expr_p (tem))
- return fold_convert (type,
- fold_build2 (TREE_CODE (t), TREE_TYPE (t),
- TREE_OPERAND (t, 0),
- negate_expr (tem)));
+ return fold_build2 (TREE_CODE (t), type,
+ TREE_OPERAND (t, 0), negate_expr (tem));
tem = TREE_OPERAND (t, 0);
if (negate_expr_p (tem))
- return fold_convert (type,
- fold_build2 (TREE_CODE (t), TREE_TYPE (t),
- negate_expr (tem),
- TREE_OPERAND (t, 1)));
+ return fold_build2 (TREE_CODE (t), type,
+ negate_expr (tem), TREE_OPERAND (t, 1));
}
break;
case FLOOR_DIV_EXPR:
case CEIL_DIV_EXPR:
case EXACT_DIV_EXPR:
- if (!TYPE_UNSIGNED (TREE_TYPE (t)) && !flag_wrapv)
+ if (!TYPE_UNSIGNED (type) && !flag_wrapv)
{
tem = TREE_OPERAND (t, 1);
if (negate_expr_p (tem))
- return fold_convert (type,
- fold_build2 (TREE_CODE (t), TREE_TYPE (t),
- TREE_OPERAND (t, 0),
- negate_expr (tem)));
+ return fold_build2 (TREE_CODE (t), type,
+ TREE_OPERAND (t, 0), negate_expr (tem));
tem = TREE_OPERAND (t, 0);
if (negate_expr_p (tem))
- return fold_convert (type,
- fold_build2 (TREE_CODE (t), TREE_TYPE (t),
- negate_expr (tem),
- TREE_OPERAND (t, 1)));
+ return fold_build2 (TREE_CODE (t), type,
+ negate_expr (tem), TREE_OPERAND (t, 1));
}
break;
{
tem = strip_float_extensions (t);
if (tem != t && negate_expr_p (tem))
- return fold_convert (type, negate_expr (tem));
+ return negate_expr (tem);
}
break;
break;
}
- tem = fold_build1 (NEGATE_EXPR, TREE_TYPE (t), t);
+ return NULL_TREE;
+}
+
+/* Like fold_negate_expr, but return a NEGATE_EXPR tree, if T can not be
+ negated in a simpler way. Also allow for T to be NULL_TREE, in which case
+ return NULL_TREE. */
+
+static tree
+negate_expr (tree t)
+{
+ tree type, tem;
+
+ if (t == NULL_TREE)
+ return NULL_TREE;
+
+ type = TREE_TYPE (t);
+ STRIP_SIGN_NOPS (t);
+
+ tem = fold_negate_expr (t);
+ if (!tem)
+ tem = build1 (NEGATE_EXPR, TREE_TYPE (t), t);
return fold_convert (type, tem);
}
\f
/* Combine two constants ARG1 and ARG2 under operation CODE to produce a new
constant. We assume ARG1 and ARG2 have the same data type, or at least
- are the same kind of constant and the same machine mode.
+ are the same kind of constant and the same machine mode. Return zero if
+ combining the constants is not allowed in the current operating mode.
If NOTRUNC is nonzero, do not truncate the result to fit the data type. */
static tree
const_binop (enum tree_code code, tree arg1, tree arg2, int notrunc)
{
+ /* Sanity check for the recursive cases. */
+ if (!arg1 || !arg2)
+ return NULL_TREE;
+
STRIP_NOPS (arg1);
STRIP_NOPS (arg2);
/* Don't constant fold this floating point operation if
the result has overflowed and flag_trapping_math. */
-
if (flag_trapping_math
&& MODE_HAS_INFINITIES (mode)
&& REAL_VALUE_ISINF (result)
result may dependent upon the run-time rounding mode and
flag_rounding_math is set, or if GCC's software emulation
is unable to accurately represent the result. */
-
if ((flag_rounding_math
|| (REAL_MODE_FORMAT_COMPOSITE_P (mode)
&& !flag_unsafe_math_optimizations))
tree i1 = TREE_IMAGPART (arg1);
tree r2 = TREE_REALPART (arg2);
tree i2 = TREE_IMAGPART (arg2);
- tree t;
+ tree real, imag;
switch (code)
{
case PLUS_EXPR:
- t = build_complex (type,
- const_binop (PLUS_EXPR, r1, r2, notrunc),
- const_binop (PLUS_EXPR, i1, i2, notrunc));
- break;
-
case MINUS_EXPR:
- t = build_complex (type,
- const_binop (MINUS_EXPR, r1, r2, notrunc),
- const_binop (MINUS_EXPR, i1, i2, notrunc));
+ real = const_binop (code, r1, r2, notrunc);
+ imag = const_binop (code, i1, i2, notrunc);
break;
case MULT_EXPR:
- t = build_complex (type,
- const_binop (MINUS_EXPR,
- const_binop (MULT_EXPR,
- r1, r2, notrunc),
- const_binop (MULT_EXPR,
- i1, i2, notrunc),
- notrunc),
- const_binop (PLUS_EXPR,
- const_binop (MULT_EXPR,
- r1, i2, notrunc),
- const_binop (MULT_EXPR,
- i1, r2, notrunc),
- notrunc));
+ real = const_binop (MINUS_EXPR,
+ const_binop (MULT_EXPR, r1, r2, notrunc),
+ const_binop (MULT_EXPR, i1, i2, notrunc),
+ notrunc);
+ imag = const_binop (PLUS_EXPR,
+ const_binop (MULT_EXPR, r1, i2, notrunc),
+ const_binop (MULT_EXPR, i1, r2, notrunc),
+ notrunc);
break;
case RDIV_EXPR:
{
- tree t1, t2, real, imag;
tree magsquared
= const_binop (PLUS_EXPR,
const_binop (MULT_EXPR, r2, r2, notrunc),
const_binop (MULT_EXPR, i2, i2, notrunc),
notrunc);
-
- t1 = const_binop (PLUS_EXPR,
- const_binop (MULT_EXPR, r1, r2, notrunc),
- const_binop (MULT_EXPR, i1, i2, notrunc),
- notrunc);
- t2 = const_binop (MINUS_EXPR,
- const_binop (MULT_EXPR, i1, r2, notrunc),
- const_binop (MULT_EXPR, r1, i2, notrunc),
- notrunc);
+ tree t1
+ = const_binop (PLUS_EXPR,
+ const_binop (MULT_EXPR, r1, r2, notrunc),
+ const_binop (MULT_EXPR, i1, i2, notrunc),
+ notrunc);
+ tree t2
+ = const_binop (MINUS_EXPR,
+ const_binop (MULT_EXPR, i1, r2, notrunc),
+ const_binop (MULT_EXPR, r1, i2, notrunc),
+ notrunc);
if (INTEGRAL_TYPE_P (TREE_TYPE (r1)))
- {
- real = const_binop (TRUNC_DIV_EXPR, t1, magsquared, notrunc);
- imag = const_binop (TRUNC_DIV_EXPR, t2, magsquared, notrunc);
- }
- else
- {
- real = const_binop (RDIV_EXPR, t1, magsquared, notrunc);
- imag = const_binop (RDIV_EXPR, t2, magsquared, notrunc);
- if (!real || !imag)
- return NULL_TREE;
- }
+ code = TRUNC_DIV_EXPR;
- t = build_complex (type, real, imag);
+ real = const_binop (code, t1, magsquared, notrunc);
+ imag = const_binop (code, t2, magsquared, notrunc);
}
break;
default:
return NULL_TREE;
}
- return t;
+
+ if (real && imag)
+ return build_complex (type, real, imag);
}
+
return NULL_TREE;
}
{
tree type = TREE_TYPE (arg0);
+ if (arg0 == error_mark_node || arg1 == error_mark_node)
+ return error_mark_node;
+
gcc_assert (TREE_CODE (type) == INTEGER_TYPE && TYPE_IS_SIZETYPE (type)
&& type == TREE_TYPE (arg1));
return int_const_binop (code, arg0, arg1, 0);
}
- if (arg0 == error_mark_node || arg1 == error_mark_node)
- return error_mark_node;
-
return fold_build2 (code, type, arg0, arg1);
}
switch (TREE_CODE (type))
{
- case INTEGER_TYPE: case CHAR_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE:
+ case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE:
case POINTER_TYPE: case REFERENCE_TYPE:
case OFFSET_TYPE:
if (TREE_CODE (arg) == INTEGER_CST)
switch (TREE_CODE (orig))
{
- case INTEGER_TYPE: case CHAR_TYPE:
+ case INTEGER_TYPE:
case BOOLEAN_TYPE: case ENUMERAL_TYPE:
case POINTER_TYPE: case REFERENCE_TYPE:
return fold_build1 (FLOAT_EXPR, type, arg);
case COMPLEX_TYPE:
switch (TREE_CODE (orig))
{
- case INTEGER_TYPE: case CHAR_TYPE:
+ case INTEGER_TYPE:
case BOOLEAN_TYPE: case ENUMERAL_TYPE:
case POINTER_TYPE: case REFERENCE_TYPE:
case REAL_TYPE:
if (TYPE_UNSIGNED (TREE_TYPE (arg0)) != TYPE_UNSIGNED (TREE_TYPE (arg1)))
return 0;
+ /* If both types don't have the same precision, then it is not safe
+ to strip NOPs. */
+ if (TYPE_PRECISION (TREE_TYPE (arg0)) != TYPE_PRECISION (TREE_TYPE (arg1)))
+ return 0;
+
STRIP_NOPS (arg0);
STRIP_NOPS (arg1);
+ /* In case both args are comparisons but with different comparison
+ code, try to swap the comparison operands of one arg to produce
+ a match and compare that variant. */
+ if (TREE_CODE (arg0) != TREE_CODE (arg1)
+ && COMPARISON_CLASS_P (arg0)
+ && COMPARISON_CLASS_P (arg1))
+ {
+ enum tree_code swap_code = swap_tree_comparison (TREE_CODE (arg1));
+
+ if (TREE_CODE (arg0) == swap_code)
+ return operand_equal_p (TREE_OPERAND (arg0, 0),
+ TREE_OPERAND (arg1, 1), flags)
+ && operand_equal_p (TREE_OPERAND (arg0, 1),
+ TREE_OPERAND (arg1, 0), flags);
+ }
+
if (TREE_CODE (arg0) != TREE_CODE (arg1)
/* This is needed for conversions and for COMPONENT_REF.
Might as well play it safe and always test this. */
FIXME: one would think we would fold the result, but it causes
problems with the dominator optimizer. */
+
tree
-invert_truthvalue (tree arg)
+fold_truth_not_expr (tree arg)
{
tree type = TREE_TYPE (arg);
enum tree_code code = TREE_CODE (arg);
- if (code == ERROR_MARK)
- return arg;
-
/* If this is a comparison, we can simply invert it, except for
floating-point non-equality comparisons, in which case we just
enclose a TRUTH_NOT_EXPR around what we have. */
&& flag_trapping_math
&& code != ORDERED_EXPR && code != UNORDERED_EXPR
&& code != NE_EXPR && code != EQ_EXPR)
- return build1 (TRUTH_NOT_EXPR, type, arg);
+ return NULL_TREE;
else
{
code = invert_tree_comparison (code,
HONOR_NANS (TYPE_MODE (op_type)));
if (code == ERROR_MARK)
- return build1 (TRUTH_NOT_EXPR, type, arg);
+ return NULL_TREE;
else
return build2 (code, type,
TREE_OPERAND (arg, 0), TREE_OPERAND (arg, 1));
case NOP_EXPR:
if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE)
- break;
+ return build1 (TRUTH_NOT_EXPR, type, arg);
case CONVERT_EXPR:
case FLOAT_EXPR:
default:
break;
}
- gcc_assert (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE);
- return build1 (TRUTH_NOT_EXPR, type, arg);
+
+ return NULL_TREE;
+}
+
+/* Return a simplified tree node for the truth-negation of ARG. This
+ never alters ARG itself. We assume that ARG is an operation that
+ returns a truth value (0 or 1).
+
+ FIXME: one would think we would fold the result, but it causes
+ problems with the dominator optimizer. */
+
+tree
+invert_truthvalue (tree arg)
+{
+ tree tem;
+
+ if (TREE_CODE (arg) == ERROR_MARK)
+ return arg;
+
+ tem = fold_truth_not_expr (arg);
+ if (!tem)
+ tem = build1 (TRUTH_NOT_EXPR, TREE_TYPE (arg), arg);
+
+ return tem;
}
/* Given a bit-wise operation CODE applied to ARG0 and ARG1, see if both
}
}
- value = const_binop (MINUS_EXPR, high, low, 0);
- if (value != 0 && (!flag_wrapv || TREE_OVERFLOW (value))
- && ! TYPE_UNSIGNED (etype))
+ /* Optimize (c>=low) && (c<=high) into (c-low>=0) && (c-low<=high-low).
+ This requires wrap-around arithmetics for the type of the expression. */
+ switch (TREE_CODE (etype))
+ {
+ case INTEGER_TYPE:
+ /* There is no requirement that LOW be within the range of ETYPE
+ if the latter is a subtype. It must, however, be within the base
+ type of ETYPE. So be sure we do the subtraction in that type. */
+ if (TREE_TYPE (etype))
+ etype = TREE_TYPE (etype);
+ break;
+
+ case ENUMERAL_TYPE:
+ case BOOLEAN_TYPE:
+ etype = lang_hooks.types.type_for_size (TYPE_PRECISION (etype),
+ TYPE_UNSIGNED (etype));
+ break;
+
+ default:
+ break;
+ }
+
+ /* If we don't have wrap-around arithmetics upfront, try to force it. */
+ if (TREE_CODE (etype) == INTEGER_TYPE
+ && !TYPE_UNSIGNED (etype) && !flag_wrapv)
{
tree utype, minv, maxv;
/* Check if (unsigned) INT_MAX + 1 == (unsigned) INT_MIN
for the type in question, as we rely on this here. */
- switch (TREE_CODE (etype))
- {
- case INTEGER_TYPE:
- case ENUMERAL_TYPE:
- case CHAR_TYPE:
- /* There is no requirement that LOW be within the range of ETYPE
- if the latter is a subtype. It must, however, be within the base
- type of ETYPE. So be sure we do the subtraction in that type. */
- if (TREE_TYPE (etype))
- etype = TREE_TYPE (etype);
- utype = lang_hooks.types.unsigned_type (etype);
- maxv = fold_convert (utype, TYPE_MAX_VALUE (etype));
- maxv = range_binop (PLUS_EXPR, NULL_TREE, maxv, 1,
- integer_one_node, 1);
- minv = fold_convert (utype, TYPE_MIN_VALUE (etype));
- if (integer_zerop (range_binop (NE_EXPR, integer_type_node,
- minv, 1, maxv, 1)))
- {
- etype = utype;
- high = fold_convert (etype, high);
- low = fold_convert (etype, low);
- exp = fold_convert (etype, exp);
- value = const_binop (MINUS_EXPR, high, low, 0);
- }
- break;
- default:
- break;
- }
+ utype = lang_hooks.types.unsigned_type (etype);
+ maxv = fold_convert (utype, TYPE_MAX_VALUE (etype));
+ maxv = range_binop (PLUS_EXPR, NULL_TREE, maxv, 1,
+ integer_one_node, 1);
+ minv = fold_convert (utype, TYPE_MIN_VALUE (etype));
+
+ if (integer_zerop (range_binop (NE_EXPR, integer_type_node,
+ minv, 1, maxv, 1)))
+ etype = utype;
+ else
+ return 0;
}
- if (value != 0 && ! TREE_OVERFLOW (value))
- {
- /* There is no requirement that LOW be within the range of ETYPE
- if the latter is a subtype. It must, however, be within the base
- type of ETYPE. So be sure we do the subtraction in that type. */
- if (INTEGRAL_TYPE_P (etype) && TREE_TYPE (etype))
- {
- etype = TREE_TYPE (etype);
- exp = fold_convert (etype, exp);
- low = fold_convert (etype, low);
- value = fold_convert (etype, value);
- }
+ high = fold_convert (etype, high);
+ low = fold_convert (etype, low);
+ exp = fold_convert (etype, exp);
- return build_range_check (type,
- fold_build2 (MINUS_EXPR, etype, exp, low),
- 1, build_int_cst (etype, 0), value);
- }
+ value = const_binop (MINUS_EXPR, high, low, 0);
+
+ if (value != 0 && !TREE_OVERFLOW (value))
+ return build_range_check (type,
+ fold_build2 (MINUS_EXPR, etype, exp, low),
+ 1, build_int_cst (etype, 0), value);
return 0;
}
\f
+/* Return the predecessor of VAL in its type, handling the infinite case. */
+
+static tree
+range_predecessor (tree val)
+{
+ tree type = TREE_TYPE (val);
+
+ if (INTEGRAL_TYPE_P (type)
+ && operand_equal_p (val, TYPE_MIN_VALUE (type), 0))
+ return 0;
+ else
+ return range_binop (MINUS_EXPR, NULL_TREE, val, 0, integer_one_node, 0);
+}
+
+/* Return the successor of VAL in its type, handling the infinite case. */
+
+static tree
+range_successor (tree val)
+{
+ tree type = TREE_TYPE (val);
+
+ if (INTEGRAL_TYPE_P (type)
+ && operand_equal_p (val, TYPE_MAX_VALUE (type), 0))
+ return 0;
+ else
+ return range_binop (PLUS_EXPR, NULL_TREE, val, 0, integer_one_node, 0);
+}
+
/* Given two ranges, see if we can merge them into one. Return 1 if we
can, 0 if we can't. Set the output range into the specified parameters. */
/* If they don't overlap, the result is the first range. If they are
equal, the result is false. If the second range is a subset of the
first, and the ranges begin at the same place, we go from just after
- the end of the first range to the end of the second. If the second
+ the end of the second range to the end of the first. If the second
range is not a subset of the first, or if it is a subset and both
ranges end at the same place, the range starts at the start of the
first range and ends just before the second range.
in_p = 0, low = high = 0;
else if (subset && lowequal)
{
- in_p = 1, high = high0;
- low = range_binop (PLUS_EXPR, NULL_TREE, high1, 0,
- integer_one_node, 0);
+ low = range_successor (high1);
+ high = high0;
+ in_p = (low != 0);
}
else if (! subset || highequal)
{
- in_p = 1, low = low0;
- high = range_binop (MINUS_EXPR, NULL_TREE, low1, 0,
- integer_one_node, 0);
+ low = low0;
+ high = range_predecessor (low1);
+ in_p = (high != 0);
}
else
return 0;
in_p = 0, low = high = 0;
else
{
- in_p = 1, high = high1;
- low = range_binop (PLUS_EXPR, NULL_TREE, high0, 1,
- integer_one_node, 0);
+ low = range_successor (high0);
+ high = high1;
+ in_p = (low != 0);
}
}
if (no_overlap)
{
if (integer_onep (range_binop (EQ_EXPR, integer_type_node,
- range_binop (PLUS_EXPR, NULL_TREE,
- high0, 1,
- integer_one_node, 1),
+ range_successor (high0),
1, low1, 0)))
in_p = 0, low = low0, high = high1;
else
break;
/* FALLTHROUGH */
case INTEGER_TYPE:
- case CHAR_TYPE:
if (tree_int_cst_equal (low0,
TYPE_MIN_VALUE (TREE_TYPE (low0))))
low0 = 0;
break;
/* FALLTHROUGH */
case INTEGER_TYPE:
- case CHAR_TYPE:
if (tree_int_cst_equal (high1,
TYPE_MAX_VALUE (TREE_TYPE (high1))))
high1 = 0;
return + [x + 1, y - 1]. */
if (low0 == 0 && high1 == 0)
{
- low = range_binop (PLUS_EXPR, NULL_TREE, high0, 1,
- integer_one_node, 1);
- high = range_binop (MINUS_EXPR, NULL_TREE, low1, 0,
- integer_one_node, 0);
+ low = range_successor (high0);
+ high = range_predecessor (low1);
if (low == 0 || high == 0)
return 0;
/* Avoid these transformations if the COND_EXPR may be used
as an lvalue in the C++ front-end. PR c++/19199. */
&& (in_gimple_form
- || strcmp (lang_hooks.name, "GNU C++") != 0
+ || (strcmp (lang_hooks.name, "GNU C++") != 0
+ && strcmp (lang_hooks.name, "GNU Objective-C++") != 0)
|| ! maybe_lvalue_p (arg1)
|| ! maybe_lvalue_p (arg2)))
{
tree lntype, rntype, result;
int first_bit, end_bit;
int volatilep;
+ tree orig_lhs = lhs, orig_rhs = rhs;
+ enum tree_code orig_code = code;
/* Start by getting the comparison codes. Fail if anything is volatile.
If one operand is a BIT_AND_EXPR with the constant one, treat it as if
build_int_cst (TREE_TYPE (ll_arg), 0));
if (LOGICAL_OP_NON_SHORT_CIRCUIT)
- return build2 (code, truth_type, lhs, rhs);
+ {
+ if (code != orig_code || lhs != orig_lhs || rhs != orig_rhs)
+ return build2 (code, truth_type, lhs, rhs);
+ return NULL_TREE;
+ }
}
/* See if the comparisons can be merged. Then get all the parameters for
{
case NE_EXPR: case LT_EXPR: case LE_EXPR:
{
- /* FIXME: We should be able to invert code without building a
- scratch tree node, but doing so would require us to
- duplicate a part of invert_truthvalue here. */
- tree tem = invert_truthvalue (build2 (code, type, op0, op1));
- tem = optimize_minmax_comparison (TREE_CODE (tem),
- TREE_TYPE (tem),
- TREE_OPERAND (tem, 0),
- TREE_OPERAND (tem, 1));
- return invert_truthvalue (tem);
+ tree tem = optimize_minmax_comparison (invert_tree_comparison (code, false),
+ type, op0, op1);
+ if (tem)
+ return invert_truthvalue (tem);
+ return NULL_TREE;
}
case GE_EXPR:
tree arg01 = TREE_OPERAND (arg0, 1);
unsigned HOST_WIDE_INT lpart;
HOST_WIDE_INT hpart;
+ bool neg_overflow;
int overflow;
/* We have to do this the hard way to detect unsigned overflow.
TREE_INT_CST_HIGH (arg1), &lpart, &hpart);
prod = build_int_cst_wide (TREE_TYPE (arg00), lpart, hpart);
prod = force_fit_type (prod, -1, overflow, false);
+ neg_overflow = false;
if (TYPE_UNSIGNED (TREE_TYPE (arg0)))
{
switch (tree_int_cst_sgn (arg1))
{
case -1:
+ neg_overflow = true;
lo = int_const_binop (MINUS_EXPR, prod, tmp, 0);
hi = prod;
break;
break;
case 1:
- lo = int_const_binop (PLUS_EXPR, prod, tmp, 0);
+ neg_overflow = true;
+ lo = int_const_binop (PLUS_EXPR, prod, tmp, 0);
hi = prod;
break;
case LT_EXPR:
if (TREE_OVERFLOW (lo))
- return omit_one_operand (type, integer_zero_node, arg00);
+ {
+ tmp = neg_overflow ? integer_zero_node : integer_one_node;
+ return omit_one_operand (type, tmp, arg00);
+ }
return fold_build2 (LT_EXPR, type, arg00, lo);
case LE_EXPR:
if (TREE_OVERFLOW (hi))
- return omit_one_operand (type, integer_one_node, arg00);
+ {
+ tmp = neg_overflow ? integer_zero_node : integer_one_node;
+ return omit_one_operand (type, tmp, arg00);
+ }
return fold_build2 (LE_EXPR, type, arg00, hi);
case GT_EXPR:
if (TREE_OVERFLOW (hi))
- return omit_one_operand (type, integer_zero_node, arg00);
+ {
+ tmp = neg_overflow ? integer_one_node : integer_zero_node;
+ return omit_one_operand (type, tmp, arg00);
+ }
return fold_build2 (GT_EXPR, type, arg00, hi);
case GE_EXPR:
if (TREE_OVERFLOW (lo))
- return omit_one_operand (type, integer_one_node, arg00);
+ {
+ tmp = neg_overflow ? integer_one_node : integer_zero_node;
+ return omit_one_operand (type, tmp, arg00);
+ }
return fold_build2 (GE_EXPR, type, arg00, lo);
default:
else
{
arg00 = arg0;
- if (!FLOAT_TYPE_P (type))
- arg01 = build_int_cst (type, 1);
- else
- arg01 = build_real (type, dconst1);
+ arg01 = build_one_cst (type);
}
if (TREE_CODE (arg1) == MULT_EXPR)
{
else
{
arg10 = arg1;
- if (!FLOAT_TYPE_P (type))
- arg11 = build_int_cst (type, 1);
- else
- arg11 = build_real (type, dconst1);
+ arg11 = build_one_cst (type);
}
same = NULL_TREE;
return NULL_TREE;
}
-/* Fold a unary expression of code CODE and type TYPE with operand
- OP0. Return the folded expression if folding is successful.
- Otherwise, return NULL_TREE. */
+/* Subroutine of native_encode_expr. Encode the INTEGER_CST
+ specified by EXPR into the buffer PTR of length LEN bytes.
+ Return the number of bytes placed in the buffer, or zero
+ upon failure. */
-tree
-fold_unary (enum tree_code code, tree type, tree op0)
+static int
+native_encode_int (tree expr, unsigned char *ptr, int len)
{
- tree tem;
- tree arg0;
- enum tree_code_class kind = TREE_CODE_CLASS (code);
+ tree type = TREE_TYPE (expr);
+ int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
+ int byte, offset, word, words;
+ unsigned char value;
- gcc_assert (IS_EXPR_CODE_CLASS (kind)
- && TREE_CODE_LENGTH (code) == 1);
+ if (total_bytes > len)
+ return 0;
+ words = total_bytes / UNITS_PER_WORD;
- arg0 = op0;
- if (arg0)
+ for (byte = 0; byte < total_bytes; byte++)
{
- if (code == NOP_EXPR || code == CONVERT_EXPR
- || code == FLOAT_EXPR || code == ABS_EXPR)
- {
- /* Don't use STRIP_NOPS, because signedness of argument type
- matters. */
- STRIP_SIGN_NOPS (arg0);
- }
+ int bitpos = byte * BITS_PER_UNIT;
+ if (bitpos < HOST_BITS_PER_WIDE_INT)
+ value = (unsigned char) (TREE_INT_CST_LOW (expr) >> bitpos);
else
- {
- /* Strip any conversions that don't change the mode. This
- is safe for every expression, except for a comparison
- expression because its signedness is derived from its
- operands.
+ value = (unsigned char) (TREE_INT_CST_HIGH (expr)
+ >> (bitpos - HOST_BITS_PER_WIDE_INT));
- Note that this is done as an internal manipulation within
- the constant folder, in order to find the simplest
- representation of the arguments so that their form can be
- studied. In any cases, the appropriate type conversions
- should be put back in the tree that will get out of the
- constant folder. */
- STRIP_NOPS (arg0);
+ if (total_bytes > UNITS_PER_WORD)
+ {
+ word = byte / UNITS_PER_WORD;
+ if (WORDS_BIG_ENDIAN)
+ word = (words - 1) - word;
+ offset = word * UNITS_PER_WORD;
+ if (BYTES_BIG_ENDIAN)
+ offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
+ else
+ offset += byte % UNITS_PER_WORD;
}
+ else
+ offset = BYTES_BIG_ENDIAN ? (total_bytes - 1) - byte : byte;
+ ptr[offset] = value;
}
+ return total_bytes;
+}
- if (TREE_CODE_CLASS (code) == tcc_unary)
+
+/* Subroutine of native_encode_expr. Encode the REAL_CST
+ specified by EXPR into the buffer PTR of length LEN bytes.
+ Return the number of bytes placed in the buffer, or zero
+ upon failure. */
+
+static int
+native_encode_real (tree expr, unsigned char *ptr, int len)
+{
+ tree type = TREE_TYPE (expr);
+ int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
+ int byte, offset, word, words;
+ unsigned char value;
+
+ /* There are always 32 bits in each long, no matter the size of
+ the hosts long. We handle floating point representations with
+ up to 192 bits. */
+ long tmp[6];
+
+ if (total_bytes > len)
+ return 0;
+ words = total_bytes / UNITS_PER_WORD;
+
+ real_to_target (tmp, TREE_REAL_CST_PTR (expr), TYPE_MODE (type));
+
+ for (byte = 0; byte < total_bytes; byte++)
{
- if (TREE_CODE (arg0) == COMPOUND_EXPR)
- return build2 (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0),
- fold_build1 (code, type, TREE_OPERAND (arg0, 1)));
- else if (TREE_CODE (arg0) == COND_EXPR)
+ int bitpos = byte * BITS_PER_UNIT;
+ value = (unsigned char) (tmp[bitpos / 32] >> (bitpos & 31));
+
+ if (total_bytes > UNITS_PER_WORD)
{
- tree arg01 = TREE_OPERAND (arg0, 1);
- tree arg02 = TREE_OPERAND (arg0, 2);
- if (! VOID_TYPE_P (TREE_TYPE (arg01)))
- arg01 = fold_build1 (code, type, arg01);
- if (! VOID_TYPE_P (TREE_TYPE (arg02)))
- arg02 = fold_build1 (code, type, arg02);
- tem = fold_build3 (COND_EXPR, type, TREE_OPERAND (arg0, 0),
- arg01, arg02);
+ word = byte / UNITS_PER_WORD;
+ if (FLOAT_WORDS_BIG_ENDIAN)
+ word = (words - 1) - word;
+ offset = word * UNITS_PER_WORD;
+ if (BYTES_BIG_ENDIAN)
+ offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
+ else
+ offset += byte % UNITS_PER_WORD;
+ }
+ else
+ offset = BYTES_BIG_ENDIAN ? (total_bytes - 1) - byte : byte;
+ ptr[offset] = value;
+ }
+ return total_bytes;
+}
- /* If this was a conversion, and all we did was to move into
- inside the COND_EXPR, bring it back out. But leave it if
- it is a conversion from integer to integer and the
- result precision is no wider than a word since such a
- conversion is cheap and may be optimized away by combine,
- while it couldn't if it were outside the COND_EXPR. Then return
- so we don't get into an infinite recursion loop taking the
- conversion out and then back in. */
+/* Subroutine of native_encode_expr. Encode the COMPLEX_CST
+ specified by EXPR into the buffer PTR of length LEN bytes.
+ Return the number of bytes placed in the buffer, or zero
+ upon failure. */
- if ((code == NOP_EXPR || code == CONVERT_EXPR
- || code == NON_LVALUE_EXPR)
- && TREE_CODE (tem) == COND_EXPR
- && TREE_CODE (TREE_OPERAND (tem, 1)) == code
+static int
+native_encode_complex (tree expr, unsigned char *ptr, int len)
+{
+ int rsize, isize;
+ tree part;
+
+ part = TREE_REALPART (expr);
+ rsize = native_encode_expr (part, ptr, len);
+ if (rsize == 0)
+ return 0;
+ part = TREE_IMAGPART (expr);
+ isize = native_encode_expr (part, ptr+rsize, len-rsize);
+ if (isize != rsize)
+ return 0;
+ return rsize + isize;
+}
+
+
+/* Subroutine of native_encode_expr. Encode the VECTOR_CST
+ specified by EXPR into the buffer PTR of length LEN bytes.
+ Return the number of bytes placed in the buffer, or zero
+ upon failure. */
+
+static int
+native_encode_vector (tree expr, unsigned char *ptr, int len)
+{
+ int i, size, offset, count;
+ tree itype, elem, elements;
+
+ offset = 0;
+ elements = TREE_VECTOR_CST_ELTS (expr);
+ count = TYPE_VECTOR_SUBPARTS (TREE_TYPE (expr));
+ itype = TREE_TYPE (TREE_TYPE (expr));
+ size = GET_MODE_SIZE (TYPE_MODE (itype));
+ for (i = 0; i < count; i++)
+ {
+ if (elements)
+ {
+ elem = TREE_VALUE (elements);
+ elements = TREE_CHAIN (elements);
+ }
+ else
+ elem = NULL_TREE;
+
+ if (elem)
+ {
+ if (native_encode_expr (elem, ptr+offset, len-offset) != size)
+ return 0;
+ }
+ else
+ {
+ if (offset + size > len)
+ return 0;
+ memset (ptr+offset, 0, size);
+ }
+ offset += size;
+ }
+ return offset;
+}
+
+
+/* Subroutine of fold_view_convert_expr. Encode the INTEGER_CST,
+ REAL_CST, COMPLEX_CST or VECTOR_CST specified by EXPR into the
+ buffer PTR of length LEN bytes. Return the number of bytes
+ placed in the buffer, or zero upon failure. */
+
+static int
+native_encode_expr (tree expr, unsigned char *ptr, int len)
+{
+ switch (TREE_CODE (expr))
+ {
+ case INTEGER_CST:
+ return native_encode_int (expr, ptr, len);
+
+ case REAL_CST:
+ return native_encode_real (expr, ptr, len);
+
+ case COMPLEX_CST:
+ return native_encode_complex (expr, ptr, len);
+
+ case VECTOR_CST:
+ return native_encode_vector (expr, ptr, len);
+
+ default:
+ return 0;
+ }
+}
+
+
+/* Subroutine of native_interpret_expr. Interpret the contents of
+ the buffer PTR of length LEN as an INTEGER_CST of type TYPE.
+ If the buffer cannot be interpreted, return NULL_TREE. */
+
+static tree
+native_interpret_int (tree type, unsigned char *ptr, int len)
+{
+ int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
+ int byte, offset, word, words;
+ unsigned char value;
+ unsigned int HOST_WIDE_INT lo = 0;
+ HOST_WIDE_INT hi = 0;
+
+ if (total_bytes > len)
+ return NULL_TREE;
+ if (total_bytes * BITS_PER_UNIT > 2 * HOST_BITS_PER_WIDE_INT)
+ return NULL_TREE;
+ words = total_bytes / UNITS_PER_WORD;
+
+ for (byte = 0; byte < total_bytes; byte++)
+ {
+ int bitpos = byte * BITS_PER_UNIT;
+ if (total_bytes > UNITS_PER_WORD)
+ {
+ word = byte / UNITS_PER_WORD;
+ if (WORDS_BIG_ENDIAN)
+ word = (words - 1) - word;
+ offset = word * UNITS_PER_WORD;
+ if (BYTES_BIG_ENDIAN)
+ offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
+ else
+ offset += byte % UNITS_PER_WORD;
+ }
+ else
+ offset = BYTES_BIG_ENDIAN ? (total_bytes - 1) - byte : byte;
+ value = ptr[offset];
+
+ if (bitpos < HOST_BITS_PER_WIDE_INT)
+ lo |= (unsigned HOST_WIDE_INT) value << bitpos;
+ else
+ hi |= (unsigned HOST_WIDE_INT) value
+ << (bitpos - HOST_BITS_PER_WIDE_INT);
+ }
+
+ return force_fit_type (build_int_cst_wide (type, lo, hi),
+ 0, false, false);
+}
+
+
+/* Subroutine of native_interpret_expr. Interpret the contents of
+ the buffer PTR of length LEN as a REAL_CST of type TYPE.
+ If the buffer cannot be interpreted, return NULL_TREE. */
+
+static tree
+native_interpret_real (tree type, unsigned char *ptr, int len)
+{
+ enum machine_mode mode = TYPE_MODE (type);
+ int total_bytes = GET_MODE_SIZE (mode);
+ int byte, offset, word, words;
+ unsigned char value;
+ /* There are always 32 bits in each long, no matter the size of
+ the hosts long. We handle floating point representations with
+ up to 192 bits. */
+ REAL_VALUE_TYPE r;
+ long tmp[6];
+
+ total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
+ if (total_bytes > len || total_bytes > 24)
+ return NULL_TREE;
+ words = total_bytes / UNITS_PER_WORD;
+
+ memset (tmp, 0, sizeof (tmp));
+ for (byte = 0; byte < total_bytes; byte++)
+ {
+ int bitpos = byte * BITS_PER_UNIT;
+ if (total_bytes > UNITS_PER_WORD)
+ {
+ word = byte / UNITS_PER_WORD;
+ if (FLOAT_WORDS_BIG_ENDIAN)
+ word = (words - 1) - word;
+ offset = word * UNITS_PER_WORD;
+ if (BYTES_BIG_ENDIAN)
+ offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
+ else
+ offset += byte % UNITS_PER_WORD;
+ }
+ else
+ offset = BYTES_BIG_ENDIAN ? (total_bytes - 1) - byte : byte;
+ value = ptr[offset];
+
+ tmp[bitpos / 32] |= (unsigned long)value << (bitpos & 31);
+ }
+
+ real_from_target (&r, tmp, mode);
+ return build_real (type, r);
+}
+
+
+/* Subroutine of native_interpret_expr. Interpret the contents of
+ the buffer PTR of length LEN as a COMPLEX_CST of type TYPE.
+ If the buffer cannot be interpreted, return NULL_TREE. */
+
+static tree
+native_interpret_complex (tree type, unsigned char *ptr, int len)
+{
+ tree etype, rpart, ipart;
+ int size;
+
+ etype = TREE_TYPE (type);
+ size = GET_MODE_SIZE (TYPE_MODE (etype));
+ if (size * 2 > len)
+ return NULL_TREE;
+ rpart = native_interpret_expr (etype, ptr, size);
+ if (!rpart)
+ return NULL_TREE;
+ ipart = native_interpret_expr (etype, ptr+size, size);
+ if (!ipart)
+ return NULL_TREE;
+ return build_complex (type, rpart, ipart);
+}
+
+
+/* Subroutine of native_interpret_expr. Interpret the contents of
+ the buffer PTR of length LEN as a VECTOR_CST of type TYPE.
+ If the buffer cannot be interpreted, return NULL_TREE. */
+
+static tree
+native_interpret_vector (tree type, unsigned char *ptr, int len)
+{
+ tree etype, elem, elements;
+ int i, size, count;
+
+ etype = TREE_TYPE (type);
+ size = GET_MODE_SIZE (TYPE_MODE (etype));
+ count = TYPE_VECTOR_SUBPARTS (type);
+ if (size * count > len)
+ return NULL_TREE;
+
+ elements = NULL_TREE;
+ for (i = count - 1; i >= 0; i--)
+ {
+ elem = native_interpret_expr (etype, ptr+(i*size), size);
+ if (!elem)
+ return NULL_TREE;
+ elements = tree_cons (NULL_TREE, elem, elements);
+ }
+ return build_vector (type, elements);
+}
+
+
+/* Subroutine of fold_view_convert_expr. Interpret the contents of
+ the buffer PTR of length LEN as a constant of type TYPE. For
+ INTEGRAL_TYPE_P we return an INTEGER_CST, for SCALAR_FLOAT_TYPE_P
+ we return a REAL_CST, etc... If the buffer cannot be interpreted,
+ return NULL_TREE. */
+
+static tree
+native_interpret_expr (tree type, unsigned char *ptr, int len)
+{
+ switch (TREE_CODE (type))
+ {
+ case INTEGER_TYPE:
+ case ENUMERAL_TYPE:
+ case BOOLEAN_TYPE:
+ return native_interpret_int (type, ptr, len);
+
+ case REAL_TYPE:
+ return native_interpret_real (type, ptr, len);
+
+ case COMPLEX_TYPE:
+ return native_interpret_complex (type, ptr, len);
+
+ case VECTOR_TYPE:
+ return native_interpret_vector (type, ptr, len);
+
+ default:
+ return NULL_TREE;
+ }
+}
+
+
+/* Fold a VIEW_CONVERT_EXPR of a constant expression EXPR to type
+ TYPE at compile-time. If we're unable to perform the conversion
+ return NULL_TREE. */
+
+static tree
+fold_view_convert_expr (tree type, tree expr)
+{
+ /* We support up to 512-bit values (for V8DFmode). */
+ unsigned char buffer[64];
+ int len;
+
+ /* Check that the host and target are sane. */
+ if (CHAR_BIT != 8 || BITS_PER_UNIT != 8)
+ return NULL_TREE;
+
+ len = native_encode_expr (expr, buffer, sizeof (buffer));
+ if (len == 0)
+ return NULL_TREE;
+
+ return native_interpret_expr (type, buffer, len);
+}
+
+
+/* Fold a unary expression of code CODE and type TYPE with operand
+ OP0. Return the folded expression if folding is successful.
+ Otherwise, return NULL_TREE. */
+
+tree
+fold_unary (enum tree_code code, tree type, tree op0)
+{
+ tree tem;
+ tree arg0;
+ enum tree_code_class kind = TREE_CODE_CLASS (code);
+
+ gcc_assert (IS_EXPR_CODE_CLASS (kind)
+ && TREE_CODE_LENGTH (code) == 1);
+
+ arg0 = op0;
+ if (arg0)
+ {
+ if (code == NOP_EXPR || code == CONVERT_EXPR
+ || code == FLOAT_EXPR || code == ABS_EXPR)
+ {
+ /* Don't use STRIP_NOPS, because signedness of argument type
+ matters. */
+ STRIP_SIGN_NOPS (arg0);
+ }
+ else
+ {
+ /* Strip any conversions that don't change the mode. This
+ is safe for every expression, except for a comparison
+ expression because its signedness is derived from its
+ operands.
+
+ Note that this is done as an internal manipulation within
+ the constant folder, in order to find the simplest
+ representation of the arguments so that their form can be
+ studied. In any cases, the appropriate type conversions
+ should be put back in the tree that will get out of the
+ constant folder. */
+ STRIP_NOPS (arg0);
+ }
+ }
+
+ if (TREE_CODE_CLASS (code) == tcc_unary)
+ {
+ if (TREE_CODE (arg0) == COMPOUND_EXPR)
+ return build2 (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0),
+ fold_build1 (code, type, TREE_OPERAND (arg0, 1)));
+ else if (TREE_CODE (arg0) == COND_EXPR)
+ {
+ tree arg01 = TREE_OPERAND (arg0, 1);
+ tree arg02 = TREE_OPERAND (arg0, 2);
+ if (! VOID_TYPE_P (TREE_TYPE (arg01)))
+ arg01 = fold_build1 (code, type, arg01);
+ if (! VOID_TYPE_P (TREE_TYPE (arg02)))
+ arg02 = fold_build1 (code, type, arg02);
+ tem = fold_build3 (COND_EXPR, type, TREE_OPERAND (arg0, 0),
+ arg01, arg02);
+
+ /* If this was a conversion, and all we did was to move into
+ inside the COND_EXPR, bring it back out. But leave it if
+ it is a conversion from integer to integer and the
+ result precision is no wider than a word since such a
+ conversion is cheap and may be optimized away by combine,
+ while it couldn't if it were outside the COND_EXPR. Then return
+ so we don't get into an infinite recursion loop taking the
+ conversion out and then back in. */
+
+ if ((code == NOP_EXPR || code == CONVERT_EXPR
+ || code == NON_LVALUE_EXPR)
+ && TREE_CODE (tem) == COND_EXPR
+ && TREE_CODE (TREE_OPERAND (tem, 1)) == code
&& TREE_CODE (TREE_OPERAND (tem, 2)) == code
&& ! VOID_TYPE_P (TREE_OPERAND (tem, 1))
&& ! VOID_TYPE_P (TREE_OPERAND (tem, 2))
type via an object of identical or wider precision, neither
conversion is needed. */
if (TYPE_MAIN_VARIANT (inside_type) == TYPE_MAIN_VARIANT (type)
- && ((inter_int && final_int) || (inter_float && final_float))
+ && (((inter_int || inter_ptr) && final_int)
+ || (inter_float && final_float))
&& inter_prec >= final_prec)
return fold_build1 (code, type, TREE_OPERAND (op0, 0));
- the initial type is a pointer type and the precisions of the
intermediate and final types differ, or
- the final type is a pointer type and the precisions of the
- initial and intermediate types differ. */
+ initial and intermediate types differ.
+ - the final type is a pointer type and the initial type not
+ - the initial type is a pointer to an array and the final type
+ not. */
if (! inside_float && ! inter_float && ! final_float
&& ! inside_vec && ! inter_vec && ! final_vec
- && (inter_prec > inside_prec || inter_prec > final_prec)
+ && (inter_prec >= inside_prec || inter_prec >= final_prec)
&& ! (inside_int && inter_int
&& inter_unsignedp != inside_unsignedp
&& inter_prec < final_prec)
&& ! (final_ptr && inside_prec != inter_prec)
&& ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (type))
&& TYPE_MODE (type) == TYPE_MODE (inter_type))
- && ! final_ptr)
+ && final_ptr == inside_ptr
+ && ! (inside_ptr
+ && TREE_CODE (TREE_TYPE (inside_type)) == ARRAY_TYPE
+ && TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
return fold_build1 (code, type, TREE_OPERAND (op0, 0));
}
TREE_OPERAND (arg0, 1));
}
+ /* Convert (T1)(~(T2)X) into ~(T1)X if T1 and T2 are integral types
+ of the same precision, and X is a integer type not narrower than
+ types T1 or T2, i.e. the cast (T2)X isn't an extension. */
+ if (INTEGRAL_TYPE_P (type)
+ && TREE_CODE (op0) == BIT_NOT_EXPR
+ && INTEGRAL_TYPE_P (TREE_TYPE (op0))
+ && (TREE_CODE (TREE_OPERAND (op0, 0)) == NOP_EXPR
+ || TREE_CODE (TREE_OPERAND (op0, 0)) == CONVERT_EXPR)
+ && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (op0)))
+ {
+ tem = TREE_OPERAND (TREE_OPERAND (op0, 0), 0);
+ if (INTEGRAL_TYPE_P (TREE_TYPE (tem))
+ && TYPE_PRECISION (type) <= TYPE_PRECISION (TREE_TYPE (tem)))
+ return fold_build1 (BIT_NOT_EXPR, type, fold_convert (type, tem));
+ }
+
tem = fold_convert_const (code, type, arg0);
return tem ? tem : NULL_TREE;
case VIEW_CONVERT_EXPR:
if (TREE_CODE (op0) == VIEW_CONVERT_EXPR)
- return build1 (VIEW_CONVERT_EXPR, type, TREE_OPERAND (op0, 0));
- return NULL_TREE;
+ return fold_build1 (VIEW_CONVERT_EXPR, type, TREE_OPERAND (op0, 0));
+ return fold_view_convert_expr (type, op0);
case NEGATE_EXPR:
- if (negate_expr_p (arg0))
- return fold_convert (type, negate_expr (arg0));
+ tem = fold_negate_expr (arg0);
+ if (tem)
+ return fold_convert (type, tem);
return NULL_TREE;
case ABS_EXPR:
case CONJ_EXPR:
if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
return fold_convert (type, arg0);
- else if (TREE_CODE (arg0) == COMPLEX_EXPR)
- return build2 (COMPLEX_EXPR, type,
- TREE_OPERAND (arg0, 0),
- negate_expr (TREE_OPERAND (arg0, 1)));
- else if (TREE_CODE (arg0) == COMPLEX_CST)
- return build_complex (type, TREE_REALPART (arg0),
- negate_expr (TREE_IMAGPART (arg0)));
- else if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
- return fold_build2 (TREE_CODE (arg0), type,
- fold_build1 (CONJ_EXPR, type,
- TREE_OPERAND (arg0, 0)),
- fold_build1 (CONJ_EXPR, type,
- TREE_OPERAND (arg0, 1)));
- else if (TREE_CODE (arg0) == CONJ_EXPR)
- return TREE_OPERAND (arg0, 0);
+ if (TREE_CODE (arg0) == COMPLEX_EXPR)
+ {
+ tree itype = TREE_TYPE (type);
+ tree rpart = fold_convert (itype, TREE_OPERAND (arg0, 0));
+ tree ipart = fold_convert (itype, TREE_OPERAND (arg0, 1));
+ return fold_build2 (COMPLEX_EXPR, type, rpart, negate_expr (ipart));
+ }
+ if (TREE_CODE (arg0) == COMPLEX_CST)
+ {
+ tree itype = TREE_TYPE (type);
+ tree rpart = fold_convert (itype, TREE_REALPART (arg0));
+ tree ipart = fold_convert (itype, TREE_IMAGPART (arg0));
+ return build_complex (type, rpart, negate_expr (ipart));
+ }
+ if (TREE_CODE (arg0) == CONJ_EXPR)
+ return fold_convert (type, TREE_OPERAND (arg0, 0));
return NULL_TREE;
case BIT_NOT_EXPR:
and its values must be 0 or 1.
("true" is a fixed value perhaps depending on the language,
but we don't handle values other than 1 correctly yet.) */
- tem = invert_truthvalue (arg0);
- /* Avoid infinite recursion. */
- if (TREE_CODE (tem) == TRUTH_NOT_EXPR)
+ tem = fold_truth_not_expr (arg0);
+ if (!tem)
return NULL_TREE;
return fold_convert (type, tem);
case REALPART_EXPR:
if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
- return NULL_TREE;
- else if (TREE_CODE (arg0) == COMPLEX_EXPR)
+ return fold_convert (type, arg0);
+ if (TREE_CODE (arg0) == COMPLEX_EXPR)
return omit_one_operand (type, TREE_OPERAND (arg0, 0),
TREE_OPERAND (arg0, 1));
- else if (TREE_CODE (arg0) == COMPLEX_CST)
- return TREE_REALPART (arg0);
- else if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
- return fold_build2 (TREE_CODE (arg0), type,
- fold_build1 (REALPART_EXPR, type,
- TREE_OPERAND (arg0, 0)),
- fold_build1 (REALPART_EXPR, type,
- TREE_OPERAND (arg0, 1)));
+ if (TREE_CODE (arg0) == COMPLEX_CST)
+ return fold_convert (type, TREE_REALPART (arg0));
+ if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
+ {
+ tree itype = TREE_TYPE (TREE_TYPE (arg0));
+ tem = fold_build2 (TREE_CODE (arg0), itype,
+ fold_build1 (REALPART_EXPR, itype,
+ TREE_OPERAND (arg0, 0)),
+ fold_build1 (REALPART_EXPR, itype,
+ TREE_OPERAND (arg0, 1)));
+ return fold_convert (type, tem);
+ }
+ if (TREE_CODE (arg0) == CONJ_EXPR)
+ {
+ tree itype = TREE_TYPE (TREE_TYPE (arg0));
+ tem = fold_build1 (REALPART_EXPR, itype, TREE_OPERAND (arg0, 0));
+ return fold_convert (type, tem);
+ }
return NULL_TREE;
case IMAGPART_EXPR:
if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
return fold_convert (type, integer_zero_node);
- else if (TREE_CODE (arg0) == COMPLEX_EXPR)
+ if (TREE_CODE (arg0) == COMPLEX_EXPR)
return omit_one_operand (type, TREE_OPERAND (arg0, 1),
TREE_OPERAND (arg0, 0));
- else if (TREE_CODE (arg0) == COMPLEX_CST)
- return TREE_IMAGPART (arg0);
- else if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
- return fold_build2 (TREE_CODE (arg0), type,
- fold_build1 (IMAGPART_EXPR, type,
- TREE_OPERAND (arg0, 0)),
- fold_build1 (IMAGPART_EXPR, type,
- TREE_OPERAND (arg0, 1)));
+ if (TREE_CODE (arg0) == COMPLEX_CST)
+ return fold_convert (type, TREE_IMAGPART (arg0));
+ if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
+ {
+ tree itype = TREE_TYPE (TREE_TYPE (arg0));
+ tem = fold_build2 (TREE_CODE (arg0), itype,
+ fold_build1 (IMAGPART_EXPR, itype,
+ TREE_OPERAND (arg0, 0)),
+ fold_build1 (IMAGPART_EXPR, itype,
+ TREE_OPERAND (arg0, 1)));
+ return fold_convert (type, tem);
+ }
+ if (TREE_CODE (arg0) == CONJ_EXPR)
+ {
+ tree itype = TREE_TYPE (TREE_TYPE (arg0));
+ tem = fold_build1 (IMAGPART_EXPR, itype, TREE_OPERAND (arg0, 0));
+ return fold_convert (type, negate_expr (tem));
+ }
return NULL_TREE;
default:
return NULL_TREE;
}
-/* Fold a binary expression of code CODE and type TYPE with operands
- OP0 and OP1. Return the folded expression if folding is
- successful. Otherwise, return NULL_TREE. */
+/* Subroutine of fold_binary. This routine performs all of the
+ transformations that are common to the equality/inequality
+ operators (EQ_EXPR and NE_EXPR) and the ordering operators
+ (LT_EXPR, LE_EXPR, GE_EXPR and GT_EXPR). Callers other than
+ fold_binary should call fold_binary. Fold a comparison with
+ tree code CODE and type TYPE with operands OP0 and OP1. Return
+ the folded comparison or NULL_TREE. */
-tree
-fold_binary (enum tree_code code, tree type, tree op0, tree op1)
+static tree
+fold_comparison (enum tree_code code, tree type, tree op0, tree op1)
{
- tree t1 = NULL_TREE;
- tree tem;
- tree arg0 = NULL_TREE, arg1 = NULL_TREE;
- enum tree_code_class kind = TREE_CODE_CLASS (code);
-
- gcc_assert (IS_EXPR_CODE_CLASS (kind)
- && TREE_CODE_LENGTH (code) == 2
- && op0 != NULL_TREE
- && op1 != NULL_TREE);
+ tree arg0, arg1, tem;
arg0 = op0;
arg1 = op1;
- /* Strip any conversions that don't change the mode. This is
- safe for every expression, except for a comparison expression
- because its signedness is derived from its operands. So, in
- the latter case, only strip conversions that don't change the
- signedness.
+ STRIP_SIGN_NOPS (arg0);
+ STRIP_SIGN_NOPS (arg1);
- Note that this is done as an internal manipulation within the
- constant folder, in order to find the simplest representation
+ tem = fold_relational_const (code, type, arg0, arg1);
+ if (tem != NULL_TREE)
+ return tem;
+
+ /* If one arg is a real or integer constant, put it last. */
+ if (tree_swap_operands_p (arg0, arg1, true))
+ return fold_build2 (swap_tree_comparison (code), type, op1, op0);
+
+ /* Transform comparisons of the form X +- C1 CMP C2 to X CMP C2 +- C1. */
+ if ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
+ && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
+ && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1))
+ && !TYPE_UNSIGNED (TREE_TYPE (arg1))
+ && !(flag_wrapv || flag_trapv))
+ && (TREE_CODE (arg1) == INTEGER_CST
+ && !TREE_OVERFLOW (arg1)))
+ {
+ tree const1 = TREE_OPERAND (arg0, 1);
+ tree const2 = arg1;
+ tree variable = TREE_OPERAND (arg0, 0);
+ tree lhs;
+ int lhs_add;
+ lhs_add = TREE_CODE (arg0) != PLUS_EXPR;
+
+ lhs = fold_build2 (lhs_add ? PLUS_EXPR : MINUS_EXPR,
+ TREE_TYPE (arg1), const2, const1);
+ if (TREE_CODE (lhs) == TREE_CODE (arg1)
+ && (TREE_CODE (lhs) != INTEGER_CST
+ || !TREE_OVERFLOW (lhs)))
+ return fold_build2 (code, type, variable, lhs);
+ }
+
+ /* If this is a comparison of two exprs that look like an ARRAY_REF of the
+ same object, then we can fold this to a comparison of the two offsets in
+ signed size type. This is possible because pointer arithmetic is
+ restricted to retain within an object and overflow on pointer differences
+ is undefined as of 6.5.6/8 and /9 with respect to the signed ptrdiff_t. */
+ if (POINTER_TYPE_P (TREE_TYPE (arg0))
+ && !flag_wrapv && !flag_trapv)
+ {
+ tree base0, offset0, base1, offset1;
+
+ if (extract_array_ref (arg0, &base0, &offset0)
+ && extract_array_ref (arg1, &base1, &offset1)
+ && operand_equal_p (base0, base1, 0))
+ {
+ tree signed_size_type_node;
+ signed_size_type_node = signed_type_for (size_type_node);
+
+ /* By converting to signed size type we cover middle-end pointer
+ arithmetic which operates on unsigned pointer types of size
+ type size and ARRAY_REF offsets which are properly sign or
+ zero extended from their type in case it is narrower than
+ size type. */
+ if (offset0 == NULL_TREE)
+ offset0 = build_int_cst (signed_size_type_node, 0);
+ else
+ offset0 = fold_convert (signed_size_type_node, offset0);
+ if (offset1 == NULL_TREE)
+ offset1 = build_int_cst (signed_size_type_node, 0);
+ else
+ offset1 = fold_convert (signed_size_type_node, offset1);
+
+ return fold_build2 (code, type, offset0, offset1);
+ }
+ }
+
+ if (FLOAT_TYPE_P (TREE_TYPE (arg0)))
+ {
+ tree targ0 = strip_float_extensions (arg0);
+ tree targ1 = strip_float_extensions (arg1);
+ tree newtype = TREE_TYPE (targ0);
+
+ if (TYPE_PRECISION (TREE_TYPE (targ1)) > TYPE_PRECISION (newtype))
+ newtype = TREE_TYPE (targ1);
+
+ /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
+ if (TYPE_PRECISION (newtype) < TYPE_PRECISION (TREE_TYPE (arg0)))
+ return fold_build2 (code, type, fold_convert (newtype, targ0),
+ fold_convert (newtype, targ1));
+
+ /* (-a) CMP (-b) -> b CMP a */
+ if (TREE_CODE (arg0) == NEGATE_EXPR
+ && TREE_CODE (arg1) == NEGATE_EXPR)
+ return fold_build2 (code, type, TREE_OPERAND (arg1, 0),
+ TREE_OPERAND (arg0, 0));
+
+ if (TREE_CODE (arg1) == REAL_CST)
+ {
+ REAL_VALUE_TYPE cst;
+ cst = TREE_REAL_CST (arg1);
+
+ /* (-a) CMP CST -> a swap(CMP) (-CST) */
+ if (TREE_CODE (arg0) == NEGATE_EXPR)
+ return fold_build2 (swap_tree_comparison (code), type,
+ TREE_OPERAND (arg0, 0),
+ build_real (TREE_TYPE (arg1),
+ REAL_VALUE_NEGATE (cst)));
+
+ /* IEEE doesn't distinguish +0 and -0 in comparisons. */
+ /* a CMP (-0) -> a CMP 0 */
+ if (REAL_VALUE_MINUS_ZERO (cst))
+ return fold_build2 (code, type, arg0,
+ build_real (TREE_TYPE (arg1), dconst0));
+
+ /* x != NaN is always true, other ops are always false. */
+ if (REAL_VALUE_ISNAN (cst)
+ && ! HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg1))))
+ {
+ tem = (code == NE_EXPR) ? integer_one_node : integer_zero_node;
+ return omit_one_operand (type, tem, arg0);
+ }
+
+ /* Fold comparisons against infinity. */
+ if (REAL_VALUE_ISINF (cst))
+ {
+ tem = fold_inf_compare (code, type, arg0, arg1);
+ if (tem != NULL_TREE)
+ return tem;
+ }
+ }
+
+ /* If this is a comparison of a real constant with a PLUS_EXPR
+ or a MINUS_EXPR of a real constant, we can convert it into a
+ comparison with a revised real constant as long as no overflow
+ occurs when unsafe_math_optimizations are enabled. */
+ if (flag_unsafe_math_optimizations
+ && TREE_CODE (arg1) == REAL_CST
+ && (TREE_CODE (arg0) == PLUS_EXPR
+ || TREE_CODE (arg0) == MINUS_EXPR)
+ && TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
+ && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR
+ ? MINUS_EXPR : PLUS_EXPR,
+ arg1, TREE_OPERAND (arg0, 1), 0))
+ && ! TREE_CONSTANT_OVERFLOW (tem))
+ return fold_build2 (code, type, TREE_OPERAND (arg0, 0), tem);
+
+ /* Likewise, we can simplify a comparison of a real constant with
+ a MINUS_EXPR whose first operand is also a real constant, i.e.
+ (c1 - x) < c2 becomes x > c1-c2. */
+ if (flag_unsafe_math_optimizations
+ && TREE_CODE (arg1) == REAL_CST
+ && TREE_CODE (arg0) == MINUS_EXPR
+ && TREE_CODE (TREE_OPERAND (arg0, 0)) == REAL_CST
+ && 0 != (tem = const_binop (MINUS_EXPR, TREE_OPERAND (arg0, 0),
+ arg1, 0))
+ && ! TREE_CONSTANT_OVERFLOW (tem))
+ return fold_build2 (swap_tree_comparison (code), type,
+ TREE_OPERAND (arg0, 1), tem);
+
+ /* Fold comparisons against built-in math functions. */
+ if (TREE_CODE (arg1) == REAL_CST
+ && flag_unsafe_math_optimizations
+ && ! flag_errno_math)
+ {
+ enum built_in_function fcode = builtin_mathfn_code (arg0);
+
+ if (fcode != END_BUILTINS)
+ {
+ tem = fold_mathfn_compare (fcode, code, type, arg0, arg1);
+ if (tem != NULL_TREE)
+ return tem;
+ }
+ }
+ }
+
+ /* Convert foo++ == CONST into ++foo == CONST + INCR. */
+ if (TREE_CONSTANT (arg1)
+ && (TREE_CODE (arg0) == POSTINCREMENT_EXPR
+ || TREE_CODE (arg0) == POSTDECREMENT_EXPR)
+ /* This optimization is invalid for ordered comparisons
+ if CONST+INCR overflows or if foo+incr might overflow.
+ This optimization is invalid for floating point due to rounding.
+ For pointer types we assume overflow doesn't happen. */
+ && (POINTER_TYPE_P (TREE_TYPE (arg0))
+ || (INTEGRAL_TYPE_P (TREE_TYPE (arg0))
+ && (code == EQ_EXPR || code == NE_EXPR))))
+ {
+ tree varop, newconst;
+
+ if (TREE_CODE (arg0) == POSTINCREMENT_EXPR)
+ {
+ newconst = fold_build2 (PLUS_EXPR, TREE_TYPE (arg0),
+ arg1, TREE_OPERAND (arg0, 1));
+ varop = build2 (PREINCREMENT_EXPR, TREE_TYPE (arg0),
+ TREE_OPERAND (arg0, 0),
+ TREE_OPERAND (arg0, 1));
+ }
+ else
+ {
+ newconst = fold_build2 (MINUS_EXPR, TREE_TYPE (arg0),
+ arg1, TREE_OPERAND (arg0, 1));
+ varop = build2 (PREDECREMENT_EXPR, TREE_TYPE (arg0),
+ TREE_OPERAND (arg0, 0),
+ TREE_OPERAND (arg0, 1));
+ }
+
+
+ /* If VAROP is a reference to a bitfield, we must mask
+ the constant by the width of the field. */
+ if (TREE_CODE (TREE_OPERAND (varop, 0)) == COMPONENT_REF
+ && DECL_BIT_FIELD (TREE_OPERAND (TREE_OPERAND (varop, 0), 1))
+ && host_integerp (DECL_SIZE (TREE_OPERAND
+ (TREE_OPERAND (varop, 0), 1)), 1))
+ {
+ tree fielddecl = TREE_OPERAND (TREE_OPERAND (varop, 0), 1);
+ HOST_WIDE_INT size = tree_low_cst (DECL_SIZE (fielddecl), 1);
+ tree folded_compare, shift;
+
+ /* First check whether the comparison would come out
+ always the same. If we don't do that we would
+ change the meaning with the masking. */
+ folded_compare = fold_build2 (code, type,
+ TREE_OPERAND (varop, 0), arg1);
+ if (TREE_CODE (folded_compare) == INTEGER_CST)
+ return omit_one_operand (type, folded_compare, varop);
+
+ shift = build_int_cst (NULL_TREE,
+ TYPE_PRECISION (TREE_TYPE (varop)) - size);
+ shift = fold_convert (TREE_TYPE (varop), shift);
+ newconst = fold_build2 (LSHIFT_EXPR, TREE_TYPE (varop),
+ newconst, shift);
+ newconst = fold_build2 (RSHIFT_EXPR, TREE_TYPE (varop),
+ newconst, shift);
+ }
+
+ return fold_build2 (code, type, varop, newconst);
+ }
+
+ if (TREE_CODE (TREE_TYPE (arg0)) == INTEGER_TYPE
+ && (TREE_CODE (arg0) == NOP_EXPR
+ || TREE_CODE (arg0) == CONVERT_EXPR))
+ {
+ /* If we are widening one operand of an integer comparison,
+ see if the other operand is similarly being widened. Perhaps we
+ can do the comparison in the narrower type. */
+ tem = fold_widened_comparison (code, type, arg0, arg1);
+ if (tem)
+ return tem;
+
+ /* Or if we are changing signedness. */
+ tem = fold_sign_changed_comparison (code, type, arg0, arg1);
+ if (tem)
+ return tem;
+ }
+
+ /* If this is comparing a constant with a MIN_EXPR or a MAX_EXPR of a
+ constant, we can simplify it. */
+ if (TREE_CODE (arg1) == INTEGER_CST
+ && (TREE_CODE (arg0) == MIN_EXPR
+ || TREE_CODE (arg0) == MAX_EXPR)
+ && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
+ {
+ tem = optimize_minmax_comparison (code, type, op0, op1);
+ if (tem)
+ return tem;
+ }
+
+ /* Simplify comparison of something with itself. (For IEEE
+ floating-point, we can only do some of these simplifications.) */
+ if (operand_equal_p (arg0, arg1, 0))
+ {
+ switch (code)
+ {
+ case EQ_EXPR:
+ if (! FLOAT_TYPE_P (TREE_TYPE (arg0))
+ || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
+ return constant_boolean_node (1, type);
+ break;
+
+ case GE_EXPR:
+ case LE_EXPR:
+ if (! FLOAT_TYPE_P (TREE_TYPE (arg0))
+ || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
+ return constant_boolean_node (1, type);
+ return fold_build2 (EQ_EXPR, type, arg0, arg1);
+
+ case NE_EXPR:
+ /* For NE, we can only do this simplification if integer
+ or we don't honor IEEE floating point NaNs. */
+ if (FLOAT_TYPE_P (TREE_TYPE (arg0))
+ && HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
+ break;
+ /* ... fall through ... */
+ case GT_EXPR:
+ case LT_EXPR:
+ return constant_boolean_node (0, type);
+ default:
+ gcc_unreachable ();
+ }
+ }
+
+ /* If we are comparing an expression that just has comparisons
+ of two integer values, arithmetic expressions of those comparisons,
+ and constants, we can simplify it. There are only three cases
+ to check: the two values can either be equal, the first can be
+ greater, or the second can be greater. Fold the expression for
+ those three values. Since each value must be 0 or 1, we have
+ eight possibilities, each of which corresponds to the constant 0
+ or 1 or one of the six possible comparisons.
+
+ This handles common cases like (a > b) == 0 but also handles
+ expressions like ((x > y) - (y > x)) > 0, which supposedly
+ occur in macroized code. */
+
+ if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) != INTEGER_CST)
+ {
+ tree cval1 = 0, cval2 = 0;
+ int save_p = 0;
+
+ if (twoval_comparison_p (arg0, &cval1, &cval2, &save_p)
+ /* Don't handle degenerate cases here; they should already
+ have been handled anyway. */
+ && cval1 != 0 && cval2 != 0
+ && ! (TREE_CONSTANT (cval1) && TREE_CONSTANT (cval2))
+ && TREE_TYPE (cval1) == TREE_TYPE (cval2)
+ && INTEGRAL_TYPE_P (TREE_TYPE (cval1))
+ && TYPE_MAX_VALUE (TREE_TYPE (cval1))
+ && TYPE_MAX_VALUE (TREE_TYPE (cval2))
+ && ! operand_equal_p (TYPE_MIN_VALUE (TREE_TYPE (cval1)),
+ TYPE_MAX_VALUE (TREE_TYPE (cval2)), 0))
+ {
+ tree maxval = TYPE_MAX_VALUE (TREE_TYPE (cval1));
+ tree minval = TYPE_MIN_VALUE (TREE_TYPE (cval1));
+
+ /* We can't just pass T to eval_subst in case cval1 or cval2
+ was the same as ARG1. */
+
+ tree high_result
+ = fold_build2 (code, type,
+ eval_subst (arg0, cval1, maxval,
+ cval2, minval),
+ arg1);
+ tree equal_result
+ = fold_build2 (code, type,
+ eval_subst (arg0, cval1, maxval,
+ cval2, maxval),
+ arg1);
+ tree low_result
+ = fold_build2 (code, type,
+ eval_subst (arg0, cval1, minval,
+ cval2, maxval),
+ arg1);
+
+ /* All three of these results should be 0 or 1. Confirm they are.
+ Then use those values to select the proper code to use. */
+
+ if (TREE_CODE (high_result) == INTEGER_CST
+ && TREE_CODE (equal_result) == INTEGER_CST
+ && TREE_CODE (low_result) == INTEGER_CST)
+ {
+ /* Make a 3-bit mask with the high-order bit being the
+ value for `>', the next for '=', and the low for '<'. */
+ switch ((integer_onep (high_result) * 4)
+ + (integer_onep (equal_result) * 2)
+ + integer_onep (low_result))
+ {
+ case 0:
+ /* Always false. */
+ return omit_one_operand (type, integer_zero_node, arg0);
+ case 1:
+ code = LT_EXPR;
+ break;
+ case 2:
+ code = EQ_EXPR;
+ break;
+ case 3:
+ code = LE_EXPR;
+ break;
+ case 4:
+ code = GT_EXPR;
+ break;
+ case 5:
+ code = NE_EXPR;
+ break;
+ case 6:
+ code = GE_EXPR;
+ break;
+ case 7:
+ /* Always true. */
+ return omit_one_operand (type, integer_one_node, arg0);
+ }
+
+ if (save_p)
+ return save_expr (build2 (code, type, cval1, cval2));
+ return fold_build2 (code, type, cval1, cval2);
+ }
+ }
+ }
+
+ /* Fold a comparison of the address of COMPONENT_REFs with the same
+ type and component to a comparison of the address of the base
+ object. In short, &x->a OP &y->a to x OP y and
+ &x->a OP &y.a to x OP &y */
+ if (TREE_CODE (arg0) == ADDR_EXPR
+ && TREE_CODE (TREE_OPERAND (arg0, 0)) == COMPONENT_REF
+ && TREE_CODE (arg1) == ADDR_EXPR
+ && TREE_CODE (TREE_OPERAND (arg1, 0)) == COMPONENT_REF)
+ {
+ tree cref0 = TREE_OPERAND (arg0, 0);
+ tree cref1 = TREE_OPERAND (arg1, 0);
+ if (TREE_OPERAND (cref0, 1) == TREE_OPERAND (cref1, 1))
+ {
+ tree op0 = TREE_OPERAND (cref0, 0);
+ tree op1 = TREE_OPERAND (cref1, 0);
+ return fold_build2 (code, type,
+ build_fold_addr_expr (op0),
+ build_fold_addr_expr (op1));
+ }
+ }
+
+ /* We can fold X/C1 op C2 where C1 and C2 are integer constants
+ into a single range test. */
+ if ((TREE_CODE (arg0) == TRUNC_DIV_EXPR
+ || TREE_CODE (arg0) == EXACT_DIV_EXPR)
+ && TREE_CODE (arg1) == INTEGER_CST
+ && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
+ && !integer_zerop (TREE_OPERAND (arg0, 1))
+ && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1))
+ && !TREE_OVERFLOW (arg1))
+ {
+ tem = fold_div_compare (code, type, arg0, arg1);
+ if (tem != NULL_TREE)
+ return tem;
+ }
+
+ return NULL_TREE;
+}
+
+
+/* Subroutine of fold_binary. Optimize complex multiplications of the
+ form z * conj(z), as pow(realpart(z),2) + pow(imagpart(z),2). The
+ argument EXPR represents the expression "z" of type TYPE. */
+
+static tree
+fold_mult_zconjz (tree type, tree expr)
+{
+ tree itype = TREE_TYPE (type);
+ tree rpart, ipart, tem;
+
+ if (TREE_CODE (expr) == COMPLEX_EXPR)
+ {
+ rpart = TREE_OPERAND (expr, 0);
+ ipart = TREE_OPERAND (expr, 1);
+ }
+ else if (TREE_CODE (expr) == COMPLEX_CST)
+ {
+ rpart = TREE_REALPART (expr);
+ ipart = TREE_IMAGPART (expr);
+ }
+ else
+ {
+ expr = save_expr (expr);
+ rpart = fold_build1 (REALPART_EXPR, itype, expr);
+ ipart = fold_build1 (IMAGPART_EXPR, itype, expr);
+ }
+
+ rpart = save_expr (rpart);
+ ipart = save_expr (ipart);
+ tem = fold_build2 (PLUS_EXPR, itype,
+ fold_build2 (MULT_EXPR, itype, rpart, rpart),
+ fold_build2 (MULT_EXPR, itype, ipart, ipart));
+ return fold_build2 (COMPLEX_EXPR, type, tem,
+ fold_convert (itype, integer_zero_node));
+}
+
+
+/* Fold a binary expression of code CODE and type TYPE with operands
+ OP0 and OP1. Return the folded expression if folding is
+ successful. Otherwise, return NULL_TREE. */
+
+tree
+fold_binary (enum tree_code code, tree type, tree op0, tree op1)
+{
+ enum tree_code_class kind = TREE_CODE_CLASS (code);
+ tree arg0, arg1, tem;
+ tree t1 = NULL_TREE;
+
+ gcc_assert (IS_EXPR_CODE_CLASS (kind)
+ && TREE_CODE_LENGTH (code) == 2
+ && op0 != NULL_TREE
+ && op1 != NULL_TREE);
+
+ arg0 = op0;
+ arg1 = op1;
+
+ /* Strip any conversions that don't change the mode. This is
+ safe for every expression, except for a comparison expression
+ because its signedness is derived from its operands. So, in
+ the latter case, only strip conversions that don't change the
+ signedness.
+
+ Note that this is done as an internal manipulation within the
+ constant folder, in order to find the simplest representation
of the arguments so that their form can be studied. In any
cases, the appropriate type conversions should be put back in
the tree that will get out of the constant folder. */
if (INTEGRAL_TYPE_P (type)
&& TREE_CODE (arg0) == NEGATE_EXPR
&& integer_onep (arg1))
- return fold_build1 (BIT_NOT_EXPR, type, TREE_OPERAND (arg0, 0));
+ return fold_build1 (BIT_NOT_EXPR, type,
+ fold_convert (type, TREE_OPERAND (arg0, 0)));
/* Convert -1 - A to ~A. */
if (INTEGRAL_TYPE_P (type)
/* (-A) * (-B) -> A * B */
if (TREE_CODE (arg0) == NEGATE_EXPR && negate_expr_p (arg1))
return fold_build2 (MULT_EXPR, type,
- TREE_OPERAND (arg0, 0),
- negate_expr (arg1));
+ fold_convert (type, TREE_OPERAND (arg0, 0)),
+ fold_convert (type, negate_expr (arg1)));
if (TREE_CODE (arg1) == NEGATE_EXPR && negate_expr_p (arg0))
return fold_build2 (MULT_EXPR, type,
- negate_expr (arg0),
- TREE_OPERAND (arg1, 0));
+ fold_convert (type, negate_expr (arg0)),
+ fold_convert (type, TREE_OPERAND (arg1, 0)));
if (! FLOAT_TYPE_P (type))
{
code, NULL_TREE)))
return fold_convert (type, tem);
+ /* Optimize z * conj(z) for integer complex numbers. */
+ if (TREE_CODE (arg0) == CONJ_EXPR
+ && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
+ return fold_mult_zconjz (type, arg1);
+ if (TREE_CODE (arg1) == CONJ_EXPR
+ && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
+ return fold_mult_zconjz (type, arg0);
}
else
{
}
}
+ /* Optimize z * conj(z) for floating point complex numbers.
+ Guarded by flag_unsafe_math_optimizations as non-finite
+ imaginary components don't produce scalar results. */
+ if (flag_unsafe_math_optimizations
+ && TREE_CODE (arg0) == CONJ_EXPR
+ && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
+ return fold_mult_zconjz (type, arg1);
+ if (flag_unsafe_math_optimizations
+ && TREE_CODE (arg1) == CONJ_EXPR
+ && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
+ return fold_mult_zconjz (type, arg0);
+
if (flag_unsafe_math_optimizations)
{
enum built_in_function fcode0 = builtin_mathfn_code (arg0);
return omit_one_operand (type, t1, arg0);
}
+ /* Canonicalize (X & C1) | C2. */
+ if (TREE_CODE (arg0) == BIT_AND_EXPR
+ && TREE_CODE (arg1) == INTEGER_CST
+ && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
+ {
+ unsigned HOST_WIDE_INT hi1, lo1, hi2, lo2, mlo, mhi;
+ int width = TYPE_PRECISION (type);
+ hi1 = TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1));
+ lo1 = TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1));
+ hi2 = TREE_INT_CST_HIGH (arg1);
+ lo2 = TREE_INT_CST_LOW (arg1);
+
+ /* If (C1&C2) == C1, then (X&C1)|C2 becomes (X,C2). */
+ if ((hi1 & hi2) == hi1 && (lo1 & lo2) == lo1)
+ return omit_one_operand (type, arg1, TREE_OPERAND (arg0, 0));
+
+ if (width > HOST_BITS_PER_WIDE_INT)
+ {
+ mhi = (unsigned HOST_WIDE_INT) -1
+ >> (2 * HOST_BITS_PER_WIDE_INT - width);
+ mlo = -1;
+ }
+ else
+ {
+ mhi = 0;
+ mlo = (unsigned HOST_WIDE_INT) -1
+ >> (HOST_BITS_PER_WIDE_INT - width);
+ }
+
+ /* If (C1|C2) == ~0 then (X&C1)|C2 becomes X|C2. */
+ if ((~(hi1 | hi2) & mhi) == 0 && (~(lo1 | lo2) & mlo) == 0)
+ return fold_build2 (BIT_IOR_EXPR, type,
+ TREE_OPERAND (arg0, 0), arg1);
+
+ /* Minimize the number of bits set in C1, i.e. C1 := C1 & ~C2. */
+ hi1 &= mhi;
+ lo1 &= mlo;
+ if ((hi1 & ~hi2) != hi1 || (lo1 & ~lo2) != lo1)
+ return fold_build2 (BIT_IOR_EXPR, type,
+ fold_build2 (BIT_AND_EXPR, type,
+ TREE_OPERAND (arg0, 0),
+ build_int_cst_wide (type,
+ lo1 & ~lo2,
+ hi1 & ~hi2)),
+ arg1);
+ }
+
+ /* (X & Y) | Y is (X, Y). */
+ if (TREE_CODE (arg0) == BIT_AND_EXPR
+ && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
+ return omit_one_operand (type, arg1, TREE_OPERAND (arg0, 0));
+ /* (X & Y) | X is (Y, X). */
+ if (TREE_CODE (arg0) == BIT_AND_EXPR
+ && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
+ && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
+ return omit_one_operand (type, arg1, TREE_OPERAND (arg0, 1));
+ /* X | (X & Y) is (Y, X). */
+ if (TREE_CODE (arg1) == BIT_AND_EXPR
+ && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0)
+ && reorder_operands_p (arg0, TREE_OPERAND (arg1, 1)))
+ return omit_one_operand (type, arg0, TREE_OPERAND (arg1, 1));
+ /* X | (Y & X) is (Y, X). */
+ if (TREE_CODE (arg1) == BIT_AND_EXPR
+ && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
+ && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
+ return omit_one_operand (type, arg0, TREE_OPERAND (arg1, 0));
+
t1 = distribute_bit_expr (code, type, arg0, arg1);
if (t1 != NULL_TREE)
return t1;
fold_convert (type, TREE_OPERAND (arg0, 0)),
fold_convert (type, TREE_OPERAND (arg1, 0)));
+ /* Fold (X & 1) ^ 1 as (X & 1) == 0. */
+ if (TREE_CODE (arg0) == BIT_AND_EXPR
+ && integer_onep (TREE_OPERAND (arg0, 1))
+ && integer_onep (arg1))
+ return fold_build2 (EQ_EXPR, type, arg0,
+ build_int_cst (TREE_TYPE (arg0), 0));
+
+ /* Fold (X & Y) ^ Y as ~X & Y. */
+ if (TREE_CODE (arg0) == BIT_AND_EXPR
+ && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
+ {
+ tem = fold_convert (type, TREE_OPERAND (arg0, 0));
+ return fold_build2 (BIT_AND_EXPR, type,
+ fold_build1 (BIT_NOT_EXPR, type, tem),
+ fold_convert (type, arg1));
+ }
+ /* Fold (X & Y) ^ X as ~Y & X. */
+ if (TREE_CODE (arg0) == BIT_AND_EXPR
+ && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
+ && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
+ {
+ tem = fold_convert (type, TREE_OPERAND (arg0, 1));
+ return fold_build2 (BIT_AND_EXPR, type,
+ fold_build1 (BIT_NOT_EXPR, type, tem),
+ fold_convert (type, arg1));
+ }
+ /* Fold X ^ (X & Y) as X & ~Y. */
+ if (TREE_CODE (arg1) == BIT_AND_EXPR
+ && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
+ {
+ tem = fold_convert (type, TREE_OPERAND (arg1, 1));
+ return fold_build2 (BIT_AND_EXPR, type,
+ fold_convert (type, arg0),
+ fold_build1 (BIT_NOT_EXPR, type, tem));
+ }
+ /* Fold X ^ (Y & X) as ~Y & X. */
+ if (TREE_CODE (arg1) == BIT_AND_EXPR
+ && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
+ && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
+ {
+ tem = fold_convert (type, TREE_OPERAND (arg1, 0));
+ return fold_build2 (BIT_AND_EXPR, type,
+ fold_build1 (BIT_NOT_EXPR, type, tem),
+ fold_convert (type, arg0));
+ }
+
/* See if this can be simplified into a rotate first. If that
is unsuccessful continue in the association code. */
goto bit_rotate;
&& operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
return omit_one_operand (type, integer_zero_node, arg0);
- t1 = distribute_bit_expr (code, type, arg0, arg1);
- if (t1 != NULL_TREE)
- return t1;
- /* Simplify ((int)c & 0377) into (int)c, if c is unsigned char. */
- if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) == NOP_EXPR
- && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0))))
- {
- unsigned int prec
+ /* Canonicalize (X | C1) & C2 as (X & C2) | (C1 & C2). */
+ if (TREE_CODE (arg0) == BIT_IOR_EXPR
+ && TREE_CODE (arg1) == INTEGER_CST
+ && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
+ return fold_build2 (BIT_IOR_EXPR, type,
+ fold_build2 (BIT_AND_EXPR, type,
+ TREE_OPERAND (arg0, 0), arg1),
+ fold_build2 (BIT_AND_EXPR, type,
+ TREE_OPERAND (arg0, 1), arg1));
+
+ /* (X | Y) & Y is (X, Y). */
+ if (TREE_CODE (arg0) == BIT_IOR_EXPR
+ && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
+ return omit_one_operand (type, arg1, TREE_OPERAND (arg0, 0));
+ /* (X | Y) & X is (Y, X). */
+ if (TREE_CODE (arg0) == BIT_IOR_EXPR
+ && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
+ && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
+ return omit_one_operand (type, arg1, TREE_OPERAND (arg0, 1));
+ /* X & (X | Y) is (Y, X). */
+ if (TREE_CODE (arg1) == BIT_IOR_EXPR
+ && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0)
+ && reorder_operands_p (arg0, TREE_OPERAND (arg1, 1)))
+ return omit_one_operand (type, arg0, TREE_OPERAND (arg1, 1));
+ /* X & (Y | X) is (Y, X). */
+ if (TREE_CODE (arg1) == BIT_IOR_EXPR
+ && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
+ && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
+ return omit_one_operand (type, arg0, TREE_OPERAND (arg1, 0));
+
+ /* Fold (X ^ 1) & 1 as (X & 1) == 0. */
+ if (TREE_CODE (arg0) == BIT_XOR_EXPR
+ && integer_onep (TREE_OPERAND (arg0, 1))
+ && integer_onep (arg1))
+ {
+ tem = TREE_OPERAND (arg0, 0);
+ return fold_build2 (EQ_EXPR, type,
+ fold_build2 (BIT_AND_EXPR, TREE_TYPE (tem), tem,
+ build_int_cst (TREE_TYPE (tem), 1)),
+ build_int_cst (TREE_TYPE (tem), 0));
+ }
+ /* Fold ~X & 1 as (X & 1) == 0. */
+ if (TREE_CODE (arg0) == BIT_NOT_EXPR
+ && integer_onep (arg1))
+ {
+ tem = TREE_OPERAND (arg0, 0);
+ return fold_build2 (EQ_EXPR, type,
+ fold_build2 (BIT_AND_EXPR, TREE_TYPE (tem), tem,
+ build_int_cst (TREE_TYPE (tem), 1)),
+ build_int_cst (TREE_TYPE (tem), 0));
+ }
+
+ /* Fold (X ^ Y) & Y as ~X & Y. */
+ if (TREE_CODE (arg0) == BIT_XOR_EXPR
+ && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
+ {
+ tem = fold_convert (type, TREE_OPERAND (arg0, 0));
+ return fold_build2 (BIT_AND_EXPR, type,
+ fold_build1 (BIT_NOT_EXPR, type, tem),
+ fold_convert (type, arg1));
+ }
+ /* Fold (X ^ Y) & X as ~Y & X. */
+ if (TREE_CODE (arg0) == BIT_XOR_EXPR
+ && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
+ && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
+ {
+ tem = fold_convert (type, TREE_OPERAND (arg0, 1));
+ return fold_build2 (BIT_AND_EXPR, type,
+ fold_build1 (BIT_NOT_EXPR, type, tem),
+ fold_convert (type, arg1));
+ }
+ /* Fold X & (X ^ Y) as X & ~Y. */
+ if (TREE_CODE (arg1) == BIT_XOR_EXPR
+ && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
+ {
+ tem = fold_convert (type, TREE_OPERAND (arg1, 1));
+ return fold_build2 (BIT_AND_EXPR, type,
+ fold_convert (type, arg0),
+ fold_build1 (BIT_NOT_EXPR, type, tem));
+ }
+ /* Fold X & (Y ^ X) as ~Y & X. */
+ if (TREE_CODE (arg1) == BIT_XOR_EXPR
+ && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
+ && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
+ {
+ tem = fold_convert (type, TREE_OPERAND (arg1, 0));
+ return fold_build2 (BIT_AND_EXPR, type,
+ fold_build1 (BIT_NOT_EXPR, type, tem),
+ fold_convert (type, arg0));
+ }
+
+ t1 = distribute_bit_expr (code, type, arg0, arg1);
+ if (t1 != NULL_TREE)
+ return t1;
+ /* Simplify ((int)c & 0377) into (int)c, if c is unsigned char. */
+ if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) == NOP_EXPR
+ && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0))))
+ {
+ unsigned int prec
= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0)));
if (prec < BITS_PER_WORD && prec < HOST_BITS_PER_WIDE_INT
return NULL_TREE;
/* Optimize A / A to 1.0 if we don't care about
- NaNs or Infinities. */
- if (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
+ NaNs or Infinities. Skip the transformation
+ for non-real operands. */
+ if (SCALAR_FLOAT_TYPE_P (TREE_TYPE (arg0))
+ && ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
&& ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg0)))
&& operand_equal_p (arg0, arg1, 0))
{
return omit_two_operands (type, r, arg0, arg1);
}
+ /* The complex version of the above A / A optimization. */
+ if (COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0))
+ && operand_equal_p (arg0, arg1, 0))
+ {
+ tree elem_type = TREE_TYPE (TREE_TYPE (arg0));
+ if (! HONOR_NANS (TYPE_MODE (elem_type))
+ && ! HONOR_INFINITIES (TYPE_MODE (elem_type)))
+ {
+ tree r = build_real (elem_type, dconst1);
+ /* omit_two_operands will call fold_convert for us. */
+ return omit_two_operands (type, r, arg0, arg1);
+ }
+ }
+
/* (-A) / (-B) -> A / B */
if (TREE_CODE (arg0) == NEGATE_EXPR && negate_expr_p (arg1))
return fold_build2 (RDIV_EXPR, type,
return NULL_TREE;
case TRUNC_DIV_EXPR:
- case ROUND_DIV_EXPR:
case FLOOR_DIV_EXPR:
+ /* Simplify A / (B << N) where A and B are positive and B is
+ a power of 2, to A >> (N + log2(B)). */
+ if (TREE_CODE (arg1) == LSHIFT_EXPR
+ && (TYPE_UNSIGNED (type) || tree_expr_nonnegative_p (arg0)))
+ {
+ tree sval = TREE_OPERAND (arg1, 0);
+ if (integer_pow2p (sval) && tree_int_cst_sgn (sval) > 0)
+ {
+ tree sh_cnt = TREE_OPERAND (arg1, 1);
+ unsigned long pow2 = exact_log2 (TREE_INT_CST_LOW (sval));
+
+ sh_cnt = fold_build2 (PLUS_EXPR, TREE_TYPE (sh_cnt),
+ sh_cnt, build_int_cst (NULL_TREE, pow2));
+ return fold_build2 (RSHIFT_EXPR, type,
+ fold_convert (type, arg0), sh_cnt);
+ }
+ }
+ /* Fall thru */
+
+ case ROUND_DIV_EXPR:
case CEIL_DIV_EXPR:
case EXACT_DIV_EXPR:
if (integer_onep (arg1))
return omit_one_operand (type, integer_zero_node, arg0);
/* Optimize TRUNC_MOD_EXPR by a power of two into a BIT_AND_EXPR,
- i.e. "X % C" into "X & C2", if X and C are positive. */
+ i.e. "X % C" into "X & (C - 1)", if X and C are positive. */
if ((code == TRUNC_MOD_EXPR || code == FLOOR_MOD_EXPR)
- && (TYPE_UNSIGNED (type) || tree_expr_nonnegative_p (arg0))
- && integer_pow2p (arg1) && tree_int_cst_sgn (arg1) >= 0)
+ && (TYPE_UNSIGNED (type) || tree_expr_nonnegative_p (arg0)))
{
- unsigned HOST_WIDE_INT high, low;
- tree mask;
- int l;
+ tree c = arg1;
+ /* Also optimize A % (C << N) where C is a power of 2,
+ to A & ((C << N) - 1). */
+ if (TREE_CODE (arg1) == LSHIFT_EXPR)
+ c = TREE_OPERAND (arg1, 0);
- l = tree_log2 (arg1);
- if (l >= HOST_BITS_PER_WIDE_INT)
+ if (integer_pow2p (c) && tree_int_cst_sgn (c) > 0)
{
- high = ((unsigned HOST_WIDE_INT) 1
- << (l - HOST_BITS_PER_WIDE_INT)) - 1;
- low = -1;
- }
- else
- {
- high = 0;
- low = ((unsigned HOST_WIDE_INT) 1 << l) - 1;
+ tree mask = fold_build2 (MINUS_EXPR, TREE_TYPE (arg1),
+ arg1, integer_one_node);
+ return fold_build2 (BIT_AND_EXPR, type,
+ fold_convert (type, arg0),
+ fold_convert (type, mask));
}
-
- mask = build_int_cst_wide (type, low, high);
- return fold_build2 (BIT_AND_EXPR, type,
- fold_convert (type, arg0), mask);
}
/* X % -C is the same as X % C. */
return NULL_TREE;
/* Turn (a OP c1) OP c2 into a OP (c1+c2). */
- if (TREE_CODE (arg0) == code && host_integerp (arg1, false)
+ if (TREE_CODE (op0) == code && host_integerp (arg1, false)
&& TREE_INT_CST_LOW (arg1) < TYPE_PRECISION (type)
&& host_integerp (TREE_OPERAND (arg0, 1), false)
&& TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)) < TYPE_PRECISION (type))
case EQ_EXPR:
case NE_EXPR:
- case LT_EXPR:
- case GT_EXPR:
- case LE_EXPR:
- case GE_EXPR:
- /* If one arg is a real or integer constant, put it last. */
- if (tree_swap_operands_p (arg0, arg1, true))
- return fold_build2 (swap_tree_comparison (code), type, op1, op0);
+ tem = fold_comparison (code, type, op0, op1);
+ if (tem != NULL_TREE)
+ return tem;
- /* ~a != C becomes a != ~C where C is a constant. Likewise for ==. */
- if (TREE_CODE (arg0) == BIT_NOT_EXPR && TREE_CODE (arg1) == INTEGER_CST
- && (code == NE_EXPR || code == EQ_EXPR))
- return fold_build2 (code, type, TREE_OPERAND (arg0, 0),
- fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg1),
- arg1));
-
/* bool_var != 0 becomes bool_var. */
if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_zerop (arg1)
&& code == NE_EXPR)
return non_lvalue (fold_convert (type, arg0));
-
+
/* bool_var == 1 becomes bool_var. */
if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_onep (arg1)
&& code == EQ_EXPR)
&& code == EQ_EXPR)
return fold_build1 (TRUTH_NOT_EXPR, type, arg0);
+ /* ~a != C becomes a != ~C where C is a constant. Likewise for ==. */
+ if (TREE_CODE (arg0) == BIT_NOT_EXPR
+ && TREE_CODE (arg1) == INTEGER_CST)
+ return fold_build2 (code, type, TREE_OPERAND (arg0, 0),
+ fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg1),
+ arg1));
+
/* If this is an equality comparison of the address of a non-weak
object against zero, then we know the result. */
- if ((code == EQ_EXPR || code == NE_EXPR)
- && TREE_CODE (arg0) == ADDR_EXPR
+ if (TREE_CODE (arg0) == ADDR_EXPR
&& VAR_OR_FUNCTION_DECL_P (TREE_OPERAND (arg0, 0))
&& ! DECL_WEAK (TREE_OPERAND (arg0, 0))
&& integer_zerop (arg1))
/* If this is an equality comparison of the address of two non-weak,
unaliased symbols neither of which are extern (since we do not
have access to attributes for externs), then we know the result. */
- if ((code == EQ_EXPR || code == NE_EXPR)
- && TREE_CODE (arg0) == ADDR_EXPR
+ if (TREE_CODE (arg0) == ADDR_EXPR
&& VAR_OR_FUNCTION_DECL_P (TREE_OPERAND (arg0, 0))
&& ! DECL_WEAK (TREE_OPERAND (arg0, 0))
&& ! lookup_attribute ("alias",
type);
}
- /* If this is a comparison of two exprs that look like an
- ARRAY_REF of the same object, then we can fold this to a
- comparison of the two offsets. */
- if (TREE_CODE_CLASS (code) == tcc_comparison)
+ /* If this is an EQ or NE comparison of a constant with a PLUS_EXPR or
+ a MINUS_EXPR of a constant, we can convert it into a comparison with
+ a revised constant as long as no overflow occurs. */
+ if (TREE_CODE (arg1) == INTEGER_CST
+ && (TREE_CODE (arg0) == PLUS_EXPR
+ || TREE_CODE (arg0) == MINUS_EXPR)
+ && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
+ && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR
+ ? MINUS_EXPR : PLUS_EXPR,
+ arg1, TREE_OPERAND (arg0, 1), 0))
+ && ! TREE_CONSTANT_OVERFLOW (tem))
+ return fold_build2 (code, type, TREE_OPERAND (arg0, 0), tem);
+
+ /* Similarly for a NEGATE_EXPR. */
+ if (TREE_CODE (arg0) == NEGATE_EXPR
+ && TREE_CODE (arg1) == INTEGER_CST
+ && 0 != (tem = negate_expr (arg1))
+ && TREE_CODE (tem) == INTEGER_CST
+ && ! TREE_CONSTANT_OVERFLOW (tem))
+ return fold_build2 (code, type, TREE_OPERAND (arg0, 0), tem);
+
+ /* If we have X - Y == 0, we can convert that to X == Y and similarly
+ for !=. Don't do this for ordered comparisons due to overflow. */
+ if (TREE_CODE (arg0) == MINUS_EXPR
+ && integer_zerop (arg1))
+ return fold_build2 (code, type,
+ TREE_OPERAND (arg0, 0), TREE_OPERAND (arg0, 1));
+
+ /* Convert ABS_EXPR<x> == 0 or ABS_EXPR<x> != 0 to x == 0 or x != 0. */
+ if (TREE_CODE (arg0) == ABS_EXPR
+ && (integer_zerop (arg1) || real_zerop (arg1)))
+ return fold_build2 (code, type, TREE_OPERAND (arg0, 0), arg1);
+
+ /* If this is an EQ or NE comparison with zero and ARG0 is
+ (1 << foo) & bar, convert it to (bar >> foo) & 1. Both require
+ two operations, but the latter can be done in one less insn
+ on machines that have only two-operand insns or on which a
+ constant cannot be the first operand. */
+ if (TREE_CODE (arg0) == BIT_AND_EXPR
+ && integer_zerop (arg1))
+ {
+ tree arg00 = TREE_OPERAND (arg0, 0);
+ tree arg01 = TREE_OPERAND (arg0, 1);
+ if (TREE_CODE (arg00) == LSHIFT_EXPR
+ && integer_onep (TREE_OPERAND (arg00, 0)))
+ return
+ fold_build2 (code, type,
+ build2 (BIT_AND_EXPR, TREE_TYPE (arg0),
+ build2 (RSHIFT_EXPR, TREE_TYPE (arg00),
+ arg01, TREE_OPERAND (arg00, 1)),
+ fold_convert (TREE_TYPE (arg0),
+ integer_one_node)),
+ arg1);
+ else if (TREE_CODE (TREE_OPERAND (arg0, 1)) == LSHIFT_EXPR
+ && integer_onep (TREE_OPERAND (TREE_OPERAND (arg0, 1), 0)))
+ return
+ fold_build2 (code, type,
+ build2 (BIT_AND_EXPR, TREE_TYPE (arg0),
+ build2 (RSHIFT_EXPR, TREE_TYPE (arg01),
+ arg00, TREE_OPERAND (arg01, 1)),
+ fold_convert (TREE_TYPE (arg0),
+ integer_one_node)),
+ arg1);
+ }
+
+ /* If this is an NE or EQ comparison of zero against the result of a
+ signed MOD operation whose second operand is a power of 2, make
+ the MOD operation unsigned since it is simpler and equivalent. */
+ if (integer_zerop (arg1)
+ && !TYPE_UNSIGNED (TREE_TYPE (arg0))
+ && (TREE_CODE (arg0) == TRUNC_MOD_EXPR
+ || TREE_CODE (arg0) == CEIL_MOD_EXPR
+ || TREE_CODE (arg0) == FLOOR_MOD_EXPR
+ || TREE_CODE (arg0) == ROUND_MOD_EXPR)
+ && integer_pow2p (TREE_OPERAND (arg0, 1)))
+ {
+ tree newtype = lang_hooks.types.unsigned_type (TREE_TYPE (arg0));
+ tree newmod = fold_build2 (TREE_CODE (arg0), newtype,
+ fold_convert (newtype,
+ TREE_OPERAND (arg0, 0)),
+ fold_convert (newtype,
+ TREE_OPERAND (arg0, 1)));
+
+ return fold_build2 (code, type, newmod,
+ fold_convert (newtype, arg1));
+ }
+
+ /* Fold ((X >> C1) & C2) == 0 and ((X >> C1) & C2) != 0 where
+ C1 is a valid shift constant, and C2 is a power of two, i.e.
+ a single bit. */
+ if (TREE_CODE (arg0) == BIT_AND_EXPR
+ && TREE_CODE (TREE_OPERAND (arg0, 0)) == RSHIFT_EXPR
+ && TREE_CODE (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1))
+ == INTEGER_CST
+ && integer_pow2p (TREE_OPERAND (arg0, 1))
+ && integer_zerop (arg1))
+ {
+ tree itype = TREE_TYPE (arg0);
+ unsigned HOST_WIDE_INT prec = TYPE_PRECISION (itype);
+ tree arg001 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 1);
+
+ /* Check for a valid shift count. */
+ if (TREE_INT_CST_HIGH (arg001) == 0
+ && TREE_INT_CST_LOW (arg001) < prec)
+ {
+ tree arg01 = TREE_OPERAND (arg0, 1);
+ tree arg000 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0);
+ unsigned HOST_WIDE_INT log2 = tree_log2 (arg01);
+ /* If (C2 << C1) doesn't overflow, then ((X >> C1) & C2) != 0
+ can be rewritten as (X & (C2 << C1)) != 0. */
+ if ((log2 + TREE_INT_CST_LOW (arg01)) < prec)
+ {
+ tem = fold_build2 (LSHIFT_EXPR, itype, arg01, arg001);
+ tem = fold_build2 (BIT_AND_EXPR, itype, arg000, tem);
+ return fold_build2 (code, type, tem, arg1);
+ }
+ /* Otherwise, for signed (arithmetic) shifts,
+ ((X >> C1) & C2) != 0 is rewritten as X < 0, and
+ ((X >> C1) & C2) == 0 is rewritten as X >= 0. */
+ else if (!TYPE_UNSIGNED (itype))
+ return fold_build2 (code == EQ_EXPR ? GE_EXPR : LT_EXPR, type,
+ arg000, build_int_cst (itype, 0));
+ /* Otherwise, of unsigned (logical) shifts,
+ ((X >> C1) & C2) != 0 is rewritten as (X,false), and
+ ((X >> C1) & C2) == 0 is rewritten as (X,true). */
+ else
+ return omit_one_operand (type,
+ code == EQ_EXPR ? integer_one_node
+ : integer_zero_node,
+ arg000);
+ }
+ }
+
+ /* If this is an NE comparison of zero with an AND of one, remove the
+ comparison since the AND will give the correct value. */
+ if (code == NE_EXPR
+ && integer_zerop (arg1)
+ && TREE_CODE (arg0) == BIT_AND_EXPR
+ && integer_onep (TREE_OPERAND (arg0, 1)))
+ return fold_convert (type, arg0);
+
+ /* If we have (A & C) == C where C is a power of 2, convert this into
+ (A & C) != 0. Similarly for NE_EXPR. */
+ if (TREE_CODE (arg0) == BIT_AND_EXPR
+ && integer_pow2p (TREE_OPERAND (arg0, 1))
+ && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
+ return fold_build2 (code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
+ arg0, fold_convert (TREE_TYPE (arg0),
+ integer_zero_node));
+
+ /* If we have (A & C) != 0 or (A & C) == 0 and C is the sign
+ bit, then fold the expression into A < 0 or A >= 0. */
+ tem = fold_single_bit_test_into_sign_test (code, arg0, arg1, type);
+ if (tem)
+ return tem;
+
+ /* If we have (A & C) == D where D & ~C != 0, convert this into 0.
+ Similarly for NE_EXPR. */
+ if (TREE_CODE (arg0) == BIT_AND_EXPR
+ && TREE_CODE (arg1) == INTEGER_CST
+ && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
+ {
+ tree notc = fold_build1 (BIT_NOT_EXPR,
+ TREE_TYPE (TREE_OPERAND (arg0, 1)),
+ TREE_OPERAND (arg0, 1));
+ tree dandnotc = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg0),
+ arg1, notc);
+ tree rslt = code == EQ_EXPR ? integer_zero_node : integer_one_node;
+ if (integer_nonzerop (dandnotc))
+ return omit_one_operand (type, rslt, arg0);
+ }
+
+ /* If we have (A | C) == D where C & ~D != 0, convert this into 0.
+ Similarly for NE_EXPR. */
+ if (TREE_CODE (arg0) == BIT_IOR_EXPR
+ && TREE_CODE (arg1) == INTEGER_CST
+ && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
+ {
+ tree notd = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg1), arg1);
+ tree candnotd = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg0),
+ TREE_OPERAND (arg0, 1), notd);
+ tree rslt = code == EQ_EXPR ? integer_zero_node : integer_one_node;
+ if (integer_nonzerop (candnotd))
+ return omit_one_operand (type, rslt, arg0);
+ }
+
+ /* If this is a comparison of a field, we may be able to simplify it. */
+ if (((TREE_CODE (arg0) == COMPONENT_REF
+ && lang_hooks.can_use_bit_fields_p ())
+ || TREE_CODE (arg0) == BIT_FIELD_REF)
+ /* Handle the constant case even without -O
+ to make sure the warnings are given. */
+ && (optimize || TREE_CODE (arg1) == INTEGER_CST))
+ {
+ t1 = optimize_bit_field_compare (code, type, arg0, arg1);
+ if (t1)
+ return t1;
+ }
+
+ /* Optimize comparisons of strlen vs zero to a compare of the
+ first character of the string vs zero. To wit,
+ strlen(ptr) == 0 => *ptr == 0
+ strlen(ptr) != 0 => *ptr != 0
+ Other cases should reduce to one of these two (or a constant)
+ due to the return value of strlen being unsigned. */
+ if (TREE_CODE (arg0) == CALL_EXPR
+ && integer_zerop (arg1))
{
- tree base0, offset0, base1, offset1;
+ tree fndecl = get_callee_fndecl (arg0);
+ tree arglist;
- if (extract_array_ref (arg0, &base0, &offset0)
- && extract_array_ref (arg1, &base1, &offset1)
- && operand_equal_p (base0, base1, 0))
+ if (fndecl
+ && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
+ && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_STRLEN
+ && (arglist = TREE_OPERAND (arg0, 1))
+ && TREE_CODE (TREE_TYPE (TREE_VALUE (arglist))) == POINTER_TYPE
+ && ! TREE_CHAIN (arglist))
{
- /* Handle no offsets on both sides specially. */
- if (offset0 == NULL_TREE
- && offset1 == NULL_TREE)
- return fold_build2 (code, type, integer_zero_node,
- integer_zero_node);
-
- if (!offset0 || !offset1
- || TREE_TYPE (offset0) == TREE_TYPE (offset1))
+ tree iref = build_fold_indirect_ref (TREE_VALUE (arglist));
+ return fold_build2 (code, type, iref,
+ build_int_cst (TREE_TYPE (iref), 0));
+ }
+ }
+
+ /* Fold (X >> C) != 0 into X < 0 if C is one less than the width
+ of X. Similarly fold (X >> C) == 0 into X >= 0. */
+ if (TREE_CODE (arg0) == RSHIFT_EXPR
+ && integer_zerop (arg1)
+ && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
+ {
+ tree arg00 = TREE_OPERAND (arg0, 0);
+ tree arg01 = TREE_OPERAND (arg0, 1);
+ tree itype = TREE_TYPE (arg00);
+ if (TREE_INT_CST_HIGH (arg01) == 0
+ && TREE_INT_CST_LOW (arg01)
+ == (unsigned HOST_WIDE_INT) (TYPE_PRECISION (itype) - 1))
+ {
+ if (TYPE_UNSIGNED (itype))
{
- if (offset0 == NULL_TREE)
- offset0 = build_int_cst (TREE_TYPE (offset1), 0);
- if (offset1 == NULL_TREE)
- offset1 = build_int_cst (TREE_TYPE (offset0), 0);
- return fold_build2 (code, type, offset0, offset1);
+ itype = lang_hooks.types.signed_type (itype);
+ arg00 = fold_convert (itype, arg00);
}
+ return fold_build2 (code == EQ_EXPR ? GE_EXPR : LT_EXPR,
+ type, arg00, build_int_cst (itype, 0));
}
}
+ /* (X ^ Y) == 0 becomes X == Y, and (X ^ Y) != 0 becomes X != Y. */
+ if (integer_zerop (arg1)
+ && TREE_CODE (arg0) == BIT_XOR_EXPR)
+ return fold_build2 (code, type, TREE_OPERAND (arg0, 0),
+ TREE_OPERAND (arg0, 1));
+
+ /* (X ^ Y) == Y becomes X == 0. We know that Y has no side-effects. */
+ if (TREE_CODE (arg0) == BIT_XOR_EXPR
+ && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
+ return fold_build2 (code, type, TREE_OPERAND (arg0, 0),
+ build_int_cst (TREE_TYPE (arg1), 0));
+ /* Likewise (X ^ Y) == X becomes Y == 0. X has no side-effects. */
+ if (TREE_CODE (arg0) == BIT_XOR_EXPR
+ && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
+ && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
+ return fold_build2 (code, type, TREE_OPERAND (arg0, 1),
+ build_int_cst (TREE_TYPE (arg1), 0));
+
+ /* (X ^ C1) op C2 can be rewritten as X op (C1 ^ C2). */
+ if (TREE_CODE (arg0) == BIT_XOR_EXPR
+ && TREE_CODE (arg1) == INTEGER_CST
+ && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
+ return fold_build2 (code, type, TREE_OPERAND (arg0, 0),
+ fold_build2 (BIT_XOR_EXPR, TREE_TYPE (arg1),
+ TREE_OPERAND (arg0, 1), arg1));
+
+ /* Fold (~X & C) == 0 into (X & C) != 0 and (~X & C) != 0 into
+ (X & C) == 0 when C is a single bit. */
+ if (TREE_CODE (arg0) == BIT_AND_EXPR
+ && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_NOT_EXPR
+ && integer_zerop (arg1)
+ && integer_pow2p (TREE_OPERAND (arg0, 1)))
+ {
+ tem = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg0),
+ TREE_OPERAND (TREE_OPERAND (arg0, 0), 0),
+ TREE_OPERAND (arg0, 1));
+ return fold_build2 (code == EQ_EXPR ? NE_EXPR : EQ_EXPR,
+ type, tem, arg1);
+ }
+
+ /* Fold ((X & C) ^ C) eq/ne 0 into (X & C) ne/eq 0, when the
+ constant C is a power of two, i.e. a single bit. */
+ if (TREE_CODE (arg0) == BIT_XOR_EXPR
+ && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR
+ && integer_zerop (arg1)
+ && integer_pow2p (TREE_OPERAND (arg0, 1))
+ && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
+ TREE_OPERAND (arg0, 1), OEP_ONLY_CONST))
+ {
+ tree arg00 = TREE_OPERAND (arg0, 0);
+ return fold_build2 (code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
+ arg00, build_int_cst (TREE_TYPE (arg00), 0));
+ }
+
+ /* Likewise, fold ((X ^ C) & C) eq/ne 0 into (X & C) ne/eq 0,
+ when is C is a power of two, i.e. a single bit. */
+ if (TREE_CODE (arg0) == BIT_AND_EXPR
+ && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_XOR_EXPR
+ && integer_zerop (arg1)
+ && integer_pow2p (TREE_OPERAND (arg0, 1))
+ && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
+ TREE_OPERAND (arg0, 1), OEP_ONLY_CONST))
+ {
+ tree arg000 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0);
+ tem = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg000),
+ arg000, TREE_OPERAND (arg0, 1));
+ return fold_build2 (code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
+ tem, build_int_cst (TREE_TYPE (tem), 0));
+ }
+
+ if (integer_zerop (arg1)
+ && tree_expr_nonzero_p (arg0))
+ {
+ tree res = constant_boolean_node (code==NE_EXPR, type);
+ return omit_one_operand (type, res, arg0);
+ }
+ return NULL_TREE;
+
+ case LT_EXPR:
+ case GT_EXPR:
+ case LE_EXPR:
+ case GE_EXPR:
+ tem = fold_comparison (code, type, op0, op1);
+ if (tem != NULL_TREE)
+ return tem;
+
/* Transform comparisons of the form X +- C CMP X. */
- if ((code != EQ_EXPR && code != NE_EXPR)
- && (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
+ if ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
&& operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
&& ((TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
&& !HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0))))
}
}
- /* Transform comparisons of the form X +- C1 CMP C2 to X CMP C2 +- C1. */
- if ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
- && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
- && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1))
- && !TYPE_UNSIGNED (TREE_TYPE (arg1))
- && !(flag_wrapv || flag_trapv))
- && (TREE_CODE (arg1) == INTEGER_CST
- && !TREE_OVERFLOW (arg1)))
- {
- tree const1 = TREE_OPERAND (arg0, 1);
- tree const2 = arg1;
- tree variable = TREE_OPERAND (arg0, 0);
- tree lhs;
- int lhs_add;
- lhs_add = TREE_CODE (arg0) != PLUS_EXPR;
-
- lhs = fold_build2 (lhs_add ? PLUS_EXPR : MINUS_EXPR,
- TREE_TYPE (arg1), const2, const1);
- if (TREE_CODE (lhs) == TREE_CODE (arg1)
- && (TREE_CODE (lhs) != INTEGER_CST
- || !TREE_OVERFLOW (lhs)))
- return fold_build2 (code, type, variable, lhs);
- }
-
- if (FLOAT_TYPE_P (TREE_TYPE (arg0)))
- {
- tree targ0 = strip_float_extensions (arg0);
- tree targ1 = strip_float_extensions (arg1);
- tree newtype = TREE_TYPE (targ0);
-
- if (TYPE_PRECISION (TREE_TYPE (targ1)) > TYPE_PRECISION (newtype))
- newtype = TREE_TYPE (targ1);
-
- /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
- if (TYPE_PRECISION (newtype) < TYPE_PRECISION (TREE_TYPE (arg0)))
- return fold_build2 (code, type, fold_convert (newtype, targ0),
- fold_convert (newtype, targ1));
-
- /* (-a) CMP (-b) -> b CMP a */
- if (TREE_CODE (arg0) == NEGATE_EXPR
- && TREE_CODE (arg1) == NEGATE_EXPR)
- return fold_build2 (code, type, TREE_OPERAND (arg1, 0),
- TREE_OPERAND (arg0, 0));
-
- if (TREE_CODE (arg1) == REAL_CST)
- {
- REAL_VALUE_TYPE cst;
- cst = TREE_REAL_CST (arg1);
-
- /* (-a) CMP CST -> a swap(CMP) (-CST) */
- if (TREE_CODE (arg0) == NEGATE_EXPR)
- return
- fold_build2 (swap_tree_comparison (code), type,
- TREE_OPERAND (arg0, 0),
- build_real (TREE_TYPE (arg1),
- REAL_VALUE_NEGATE (cst)));
-
- /* IEEE doesn't distinguish +0 and -0 in comparisons. */
- /* a CMP (-0) -> a CMP 0 */
- if (REAL_VALUE_MINUS_ZERO (cst))
- return fold_build2 (code, type, arg0,
- build_real (TREE_TYPE (arg1), dconst0));
-
- /* x != NaN is always true, other ops are always false. */
- if (REAL_VALUE_ISNAN (cst)
- && ! HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg1))))
- {
- tem = (code == NE_EXPR) ? integer_one_node : integer_zero_node;
- return omit_one_operand (type, tem, arg0);
- }
-
- /* Fold comparisons against infinity. */
- if (REAL_VALUE_ISINF (cst))
- {
- tem = fold_inf_compare (code, type, arg0, arg1);
- if (tem != NULL_TREE)
- return tem;
- }
- }
-
- /* If this is a comparison of a real constant with a PLUS_EXPR
- or a MINUS_EXPR of a real constant, we can convert it into a
- comparison with a revised real constant as long as no overflow
- occurs when unsafe_math_optimizations are enabled. */
- if (flag_unsafe_math_optimizations
- && TREE_CODE (arg1) == REAL_CST
- && (TREE_CODE (arg0) == PLUS_EXPR
- || TREE_CODE (arg0) == MINUS_EXPR)
- && TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
- && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR
- ? MINUS_EXPR : PLUS_EXPR,
- arg1, TREE_OPERAND (arg0, 1), 0))
- && ! TREE_CONSTANT_OVERFLOW (tem))
- return fold_build2 (code, type, TREE_OPERAND (arg0, 0), tem);
-
- /* Likewise, we can simplify a comparison of a real constant with
- a MINUS_EXPR whose first operand is also a real constant, i.e.
- (c1 - x) < c2 becomes x > c1-c2. */
- if (flag_unsafe_math_optimizations
- && TREE_CODE (arg1) == REAL_CST
- && TREE_CODE (arg0) == MINUS_EXPR
- && TREE_CODE (TREE_OPERAND (arg0, 0)) == REAL_CST
- && 0 != (tem = const_binop (MINUS_EXPR, TREE_OPERAND (arg0, 0),
- arg1, 0))
- && ! TREE_CONSTANT_OVERFLOW (tem))
- return fold_build2 (swap_tree_comparison (code), type,
- TREE_OPERAND (arg0, 1), tem);
-
- /* Fold comparisons against built-in math functions. */
- if (TREE_CODE (arg1) == REAL_CST
- && flag_unsafe_math_optimizations
- && ! flag_errno_math)
- {
- enum built_in_function fcode = builtin_mathfn_code (arg0);
-
- if (fcode != END_BUILTINS)
- {
- tem = fold_mathfn_compare (fcode, code, type, arg0, arg1);
- if (tem != NULL_TREE)
- return tem;
- }
- }
- }
-
- /* Convert foo++ == CONST into ++foo == CONST + INCR. */
- if (TREE_CONSTANT (arg1)
- && (TREE_CODE (arg0) == POSTINCREMENT_EXPR
- || TREE_CODE (arg0) == POSTDECREMENT_EXPR)
- /* This optimization is invalid for ordered comparisons
- if CONST+INCR overflows or if foo+incr might overflow.
- This optimization is invalid for floating point due to rounding.
- For pointer types we assume overflow doesn't happen. */
- && (POINTER_TYPE_P (TREE_TYPE (arg0))
- || (INTEGRAL_TYPE_P (TREE_TYPE (arg0))
- && (code == EQ_EXPR || code == NE_EXPR))))
- {
- tree varop, newconst;
-
- if (TREE_CODE (arg0) == POSTINCREMENT_EXPR)
- {
- newconst = fold_build2 (PLUS_EXPR, TREE_TYPE (arg0),
- arg1, TREE_OPERAND (arg0, 1));
- varop = build2 (PREINCREMENT_EXPR, TREE_TYPE (arg0),
- TREE_OPERAND (arg0, 0),
- TREE_OPERAND (arg0, 1));
- }
- else
- {
- newconst = fold_build2 (MINUS_EXPR, TREE_TYPE (arg0),
- arg1, TREE_OPERAND (arg0, 1));
- varop = build2 (PREDECREMENT_EXPR, TREE_TYPE (arg0),
- TREE_OPERAND (arg0, 0),
- TREE_OPERAND (arg0, 1));
- }
-
-
- /* If VAROP is a reference to a bitfield, we must mask
- the constant by the width of the field. */
- if (TREE_CODE (TREE_OPERAND (varop, 0)) == COMPONENT_REF
- && DECL_BIT_FIELD (TREE_OPERAND (TREE_OPERAND (varop, 0), 1))
- && host_integerp (DECL_SIZE (TREE_OPERAND
- (TREE_OPERAND (varop, 0), 1)), 1))
- {
- tree fielddecl = TREE_OPERAND (TREE_OPERAND (varop, 0), 1);
- HOST_WIDE_INT size = tree_low_cst (DECL_SIZE (fielddecl), 1);
- tree folded_compare, shift;
-
- /* First check whether the comparison would come out
- always the same. If we don't do that we would
- change the meaning with the masking. */
- folded_compare = fold_build2 (code, type,
- TREE_OPERAND (varop, 0), arg1);
- if (integer_zerop (folded_compare)
- || integer_onep (folded_compare))
- return omit_one_operand (type, folded_compare, varop);
-
- shift = build_int_cst (NULL_TREE,
- TYPE_PRECISION (TREE_TYPE (varop)) - size);
- shift = fold_convert (TREE_TYPE (varop), shift);
- newconst = fold_build2 (LSHIFT_EXPR, TREE_TYPE (varop),
- newconst, shift);
- newconst = fold_build2 (RSHIFT_EXPR, TREE_TYPE (varop),
- newconst, shift);
- }
-
- return fold_build2 (code, type, varop, newconst);
- }
-
/* Change X >= C to X > (C - 1) and X < C to X <= (C - 1) if C > 0.
This transformation affects the cases which are handled in later
optimizations involving comparisons with non-negative constants. */
&& TREE_CODE (arg0) != INTEGER_CST
&& tree_int_cst_sgn (arg1) > 0)
{
- switch (code)
+ if (code == GE_EXPR)
{
- case GE_EXPR:
arg1 = const_binop (MINUS_EXPR, arg1,
build_int_cst (TREE_TYPE (arg1), 1), 0);
return fold_build2 (GT_EXPR, type, arg0,
fold_convert (TREE_TYPE (arg0), arg1));
-
- case LT_EXPR:
+ }
+ if (code == LT_EXPR)
+ {
arg1 = const_binop (MINUS_EXPR, arg1,
build_int_cst (TREE_TYPE (arg1), 1), 0);
return fold_build2 (LE_EXPR, type, arg0,
fold_convert (TREE_TYPE (arg0), arg1));
-
- default:
- break;
}
}
&& TYPE_UNSIGNED (TREE_TYPE (arg1))
/* signed_type does not work on pointer types. */
&& INTEGRAL_TYPE_P (TREE_TYPE (arg1)))
- {
- /* The following case also applies to X < signed_max+1
- and X >= signed_max+1 because previous transformations. */
- if (code == LE_EXPR || code == GT_EXPR)
- {
- tree st0, st1;
- st0 = lang_hooks.types.signed_type (TREE_TYPE (arg0));
- st1 = lang_hooks.types.signed_type (TREE_TYPE (arg1));
- return fold_build2 (code == LE_EXPR ? GE_EXPR: LT_EXPR,
- type, fold_convert (st0, arg0),
- build_int_cst (st1, 0));
- }
- }
- }
- }
-
- /* If this is an EQ or NE comparison of a constant with a PLUS_EXPR or
- a MINUS_EXPR of a constant, we can convert it into a comparison with
- a revised constant as long as no overflow occurs. */
- if ((code == EQ_EXPR || code == NE_EXPR)
- && TREE_CODE (arg1) == INTEGER_CST
- && (TREE_CODE (arg0) == PLUS_EXPR
- || TREE_CODE (arg0) == MINUS_EXPR)
- && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
- && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR
- ? MINUS_EXPR : PLUS_EXPR,
- arg1, TREE_OPERAND (arg0, 1), 0))
- && ! TREE_CONSTANT_OVERFLOW (tem))
- return fold_build2 (code, type, TREE_OPERAND (arg0, 0), tem);
-
- /* Similarly for a NEGATE_EXPR. */
- else if ((code == EQ_EXPR || code == NE_EXPR)
- && TREE_CODE (arg0) == NEGATE_EXPR
- && TREE_CODE (arg1) == INTEGER_CST
- && 0 != (tem = negate_expr (arg1))
- && TREE_CODE (tem) == INTEGER_CST
- && ! TREE_CONSTANT_OVERFLOW (tem))
- return fold_build2 (code, type, TREE_OPERAND (arg0, 0), tem);
-
- /* If we have X - Y == 0, we can convert that to X == Y and similarly
- for !=. Don't do this for ordered comparisons due to overflow. */
- else if ((code == NE_EXPR || code == EQ_EXPR)
- && integer_zerop (arg1) && TREE_CODE (arg0) == MINUS_EXPR)
- return fold_build2 (code, type,
- TREE_OPERAND (arg0, 0), TREE_OPERAND (arg0, 1));
-
- else if (TREE_CODE (TREE_TYPE (arg0)) == INTEGER_TYPE
- && (TREE_CODE (arg0) == NOP_EXPR
- || TREE_CODE (arg0) == CONVERT_EXPR))
- {
- /* If we are widening one operand of an integer comparison,
- see if the other operand is similarly being widened. Perhaps we
- can do the comparison in the narrower type. */
- tem = fold_widened_comparison (code, type, arg0, arg1);
- if (tem)
- return tem;
-
- /* Or if we are changing signedness. */
- tem = fold_sign_changed_comparison (code, type, arg0, arg1);
- if (tem)
- return tem;
- }
-
- /* If this is comparing a constant with a MIN_EXPR or a MAX_EXPR of a
- constant, we can simplify it. */
- else if (TREE_CODE (arg1) == INTEGER_CST
- && (TREE_CODE (arg0) == MIN_EXPR
- || TREE_CODE (arg0) == MAX_EXPR)
- && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
- {
- tem = optimize_minmax_comparison (code, type, op0, op1);
- if (tem)
- return tem;
-
- return NULL_TREE;
- }
+ {
+ /* The following case also applies to X < signed_max+1
+ and X >= signed_max+1 because previous transformations. */
+ if (code == LE_EXPR || code == GT_EXPR)
+ {
+ tree st0, st1;
+ st0 = lang_hooks.types.signed_type (TREE_TYPE (arg0));
+ st1 = lang_hooks.types.signed_type (TREE_TYPE (arg1));
+ return fold_build2 (code == LE_EXPR ? GE_EXPR: LT_EXPR,
+ type, fold_convert (st0, arg0),
+ build_int_cst (st1, 0));
+ }
+ }
+ }
+ }
/* If we are comparing an ABS_EXPR with a constant, we can
convert all the cases into explicit comparisons, but they may
well not be faster than doing the ABS and one comparison.
But ABS (X) <= C is a range comparison, which becomes a subtraction
and a comparison, and is probably faster. */
- else if (code == LE_EXPR && TREE_CODE (arg1) == INTEGER_CST
- && TREE_CODE (arg0) == ABS_EXPR
- && ! TREE_SIDE_EFFECTS (arg0)
- && (0 != (tem = negate_expr (arg1)))
- && TREE_CODE (tem) == INTEGER_CST
- && ! TREE_CONSTANT_OVERFLOW (tem))
+ if (code == LE_EXPR
+ && TREE_CODE (arg1) == INTEGER_CST
+ && TREE_CODE (arg0) == ABS_EXPR
+ && ! TREE_SIDE_EFFECTS (arg0)
+ && (0 != (tem = negate_expr (arg1)))
+ && TREE_CODE (tem) == INTEGER_CST
+ && ! TREE_CONSTANT_OVERFLOW (tem))
return fold_build2 (TRUTH_ANDIF_EXPR, type,
build2 (GE_EXPR, type,
TREE_OPERAND (arg0, 0), tem),
TREE_OPERAND (arg0, 0), arg1));
/* Convert ABS_EXPR<x> >= 0 to true. */
- else if (code == GE_EXPR
- && tree_expr_nonnegative_p (arg0)
- && (integer_zerop (arg1)
- || (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
- && real_zerop (arg1))))
+ if (code == GE_EXPR
+ && tree_expr_nonnegative_p (arg0)
+ && (integer_zerop (arg1)
+ || (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
+ && real_zerop (arg1))))
return omit_one_operand (type, integer_one_node, arg0);
/* Convert ABS_EXPR<x> < 0 to false. */
- else if (code == LT_EXPR
- && tree_expr_nonnegative_p (arg0)
- && (integer_zerop (arg1) || real_zerop (arg1)))
+ if (code == LT_EXPR
+ && tree_expr_nonnegative_p (arg0)
+ && (integer_zerop (arg1) || real_zerop (arg1)))
return omit_one_operand (type, integer_zero_node, arg0);
- /* Convert ABS_EXPR<x> == 0 or ABS_EXPR<x> != 0 to x == 0 or x != 0. */
- else if ((code == EQ_EXPR || code == NE_EXPR)
- && TREE_CODE (arg0) == ABS_EXPR
- && (integer_zerop (arg1) || real_zerop (arg1)))
- return fold_build2 (code, type, TREE_OPERAND (arg0, 0), arg1);
-
- /* If this is an EQ or NE comparison with zero and ARG0 is
- (1 << foo) & bar, convert it to (bar >> foo) & 1. Both require
- two operations, but the latter can be done in one less insn
- on machines that have only two-operand insns or on which a
- constant cannot be the first operand. */
- if (integer_zerop (arg1) && (code == EQ_EXPR || code == NE_EXPR)
- && TREE_CODE (arg0) == BIT_AND_EXPR)
- {
- tree arg00 = TREE_OPERAND (arg0, 0);
- tree arg01 = TREE_OPERAND (arg0, 1);
- if (TREE_CODE (arg00) == LSHIFT_EXPR
- && integer_onep (TREE_OPERAND (arg00, 0)))
- return
- fold_build2 (code, type,
- build2 (BIT_AND_EXPR, TREE_TYPE (arg0),
- build2 (RSHIFT_EXPR, TREE_TYPE (arg00),
- arg01, TREE_OPERAND (arg00, 1)),
- fold_convert (TREE_TYPE (arg0),
- integer_one_node)),
- arg1);
- else if (TREE_CODE (TREE_OPERAND (arg0, 1)) == LSHIFT_EXPR
- && integer_onep (TREE_OPERAND (TREE_OPERAND (arg0, 1), 0)))
- return
- fold_build2 (code, type,
- build2 (BIT_AND_EXPR, TREE_TYPE (arg0),
- build2 (RSHIFT_EXPR, TREE_TYPE (arg01),
- arg00, TREE_OPERAND (arg01, 1)),
- fold_convert (TREE_TYPE (arg0),
- integer_one_node)),
- arg1);
- }
-
- /* If this is an NE or EQ comparison of zero against the result of a
- signed MOD operation whose second operand is a power of 2, make
- the MOD operation unsigned since it is simpler and equivalent. */
- if ((code == NE_EXPR || code == EQ_EXPR)
- && integer_zerop (arg1)
- && !TYPE_UNSIGNED (TREE_TYPE (arg0))
- && (TREE_CODE (arg0) == TRUNC_MOD_EXPR
- || TREE_CODE (arg0) == CEIL_MOD_EXPR
- || TREE_CODE (arg0) == FLOOR_MOD_EXPR
- || TREE_CODE (arg0) == ROUND_MOD_EXPR)
- && integer_pow2p (TREE_OPERAND (arg0, 1)))
- {
- tree newtype = lang_hooks.types.unsigned_type (TREE_TYPE (arg0));
- tree newmod = fold_build2 (TREE_CODE (arg0), newtype,
- fold_convert (newtype,
- TREE_OPERAND (arg0, 0)),
- fold_convert (newtype,
- TREE_OPERAND (arg0, 1)));
-
- return fold_build2 (code, type, newmod,
- fold_convert (newtype, arg1));
- }
-
- /* If this is an NE comparison of zero with an AND of one, remove the
- comparison since the AND will give the correct value. */
- if (code == NE_EXPR && integer_zerop (arg1)
- && TREE_CODE (arg0) == BIT_AND_EXPR
- && integer_onep (TREE_OPERAND (arg0, 1)))
- return fold_convert (type, arg0);
-
- /* If we have (A & C) == C where C is a power of 2, convert this into
- (A & C) != 0. Similarly for NE_EXPR. */
- if ((code == EQ_EXPR || code == NE_EXPR)
- && TREE_CODE (arg0) == BIT_AND_EXPR
- && integer_pow2p (TREE_OPERAND (arg0, 1))
- && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
- return fold_build2 (code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
- arg0, fold_convert (TREE_TYPE (arg0),
- integer_zero_node));
-
- /* If we have (A & C) != 0 or (A & C) == 0 and C is the sign
- bit, then fold the expression into A < 0 or A >= 0. */
- tem = fold_single_bit_test_into_sign_test (code, arg0, arg1, type);
- if (tem)
- return tem;
-
- /* If we have (A & C) == D where D & ~C != 0, convert this into 0.
- Similarly for NE_EXPR. */
- if ((code == EQ_EXPR || code == NE_EXPR)
- && TREE_CODE (arg0) == BIT_AND_EXPR
- && TREE_CODE (arg1) == INTEGER_CST
- && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
- {
- tree notc = fold_build1 (BIT_NOT_EXPR,
- TREE_TYPE (TREE_OPERAND (arg0, 1)),
- TREE_OPERAND (arg0, 1));
- tree dandnotc = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg0),
- arg1, notc);
- tree rslt = code == EQ_EXPR ? integer_zero_node : integer_one_node;
- if (integer_nonzerop (dandnotc))
- return omit_one_operand (type, rslt, arg0);
- }
-
- /* If we have (A | C) == D where C & ~D != 0, convert this into 0.
- Similarly for NE_EXPR. */
- if ((code == EQ_EXPR || code == NE_EXPR)
- && TREE_CODE (arg0) == BIT_IOR_EXPR
- && TREE_CODE (arg1) == INTEGER_CST
- && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
- {
- tree notd = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg1), arg1);
- tree candnotd = fold_build2 (BIT_AND_EXPR, TREE_TYPE (arg0),
- TREE_OPERAND (arg0, 1), notd);
- tree rslt = code == EQ_EXPR ? integer_zero_node : integer_one_node;
- if (integer_nonzerop (candnotd))
- return omit_one_operand (type, rslt, arg0);
- }
-
/* If X is unsigned, convert X < (1 << Y) into X >> Y == 0
and similarly for >= into !=. */
if ((code == LT_EXPR || code == GE_EXPR)
TREE_OPERAND (arg1, 1)),
build_int_cst (TREE_TYPE (arg0), 0));
- else if ((code == LT_EXPR || code == GE_EXPR)
- && TYPE_UNSIGNED (TREE_TYPE (arg0))
- && (TREE_CODE (arg1) == NOP_EXPR
- || TREE_CODE (arg1) == CONVERT_EXPR)
- && TREE_CODE (TREE_OPERAND (arg1, 0)) == LSHIFT_EXPR
- && integer_onep (TREE_OPERAND (TREE_OPERAND (arg1, 0), 0)))
+ if ((code == LT_EXPR || code == GE_EXPR)
+ && TYPE_UNSIGNED (TREE_TYPE (arg0))
+ && (TREE_CODE (arg1) == NOP_EXPR
+ || TREE_CODE (arg1) == CONVERT_EXPR)
+ && TREE_CODE (TREE_OPERAND (arg1, 0)) == LSHIFT_EXPR
+ && integer_onep (TREE_OPERAND (TREE_OPERAND (arg1, 0), 0)))
return
build2 (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type,
fold_convert (TREE_TYPE (arg0),
1))),
build_int_cst (TREE_TYPE (arg0), 0));
- /* Simplify comparison of something with itself. (For IEEE
- floating-point, we can only do some of these simplifications.) */
- if (operand_equal_p (arg0, arg1, 0))
- {
- switch (code)
- {
- case EQ_EXPR:
- if (! FLOAT_TYPE_P (TREE_TYPE (arg0))
- || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
- return constant_boolean_node (1, type);
- break;
-
- case GE_EXPR:
- case LE_EXPR:
- if (! FLOAT_TYPE_P (TREE_TYPE (arg0))
- || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
- return constant_boolean_node (1, type);
- return fold_build2 (EQ_EXPR, type, arg0, arg1);
-
- case NE_EXPR:
- /* For NE, we can only do this simplification if integer
- or we don't honor IEEE floating point NaNs. */
- if (FLOAT_TYPE_P (TREE_TYPE (arg0))
- && HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
- break;
- /* ... fall through ... */
- case GT_EXPR:
- case LT_EXPR:
- return constant_boolean_node (0, type);
- default:
- gcc_unreachable ();
- }
- }
-
- /* If we are comparing an expression that just has comparisons
- of two integer values, arithmetic expressions of those comparisons,
- and constants, we can simplify it. There are only three cases
- to check: the two values can either be equal, the first can be
- greater, or the second can be greater. Fold the expression for
- those three values. Since each value must be 0 or 1, we have
- eight possibilities, each of which corresponds to the constant 0
- or 1 or one of the six possible comparisons.
-
- This handles common cases like (a > b) == 0 but also handles
- expressions like ((x > y) - (y > x)) > 0, which supposedly
- occur in macroized code. */
-
- if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) != INTEGER_CST)
- {
- tree cval1 = 0, cval2 = 0;
- int save_p = 0;
-
- if (twoval_comparison_p (arg0, &cval1, &cval2, &save_p)
- /* Don't handle degenerate cases here; they should already
- have been handled anyway. */
- && cval1 != 0 && cval2 != 0
- && ! (TREE_CONSTANT (cval1) && TREE_CONSTANT (cval2))
- && TREE_TYPE (cval1) == TREE_TYPE (cval2)
- && INTEGRAL_TYPE_P (TREE_TYPE (cval1))
- && TYPE_MAX_VALUE (TREE_TYPE (cval1))
- && TYPE_MAX_VALUE (TREE_TYPE (cval2))
- && ! operand_equal_p (TYPE_MIN_VALUE (TREE_TYPE (cval1)),
- TYPE_MAX_VALUE (TREE_TYPE (cval2)), 0))
- {
- tree maxval = TYPE_MAX_VALUE (TREE_TYPE (cval1));
- tree minval = TYPE_MIN_VALUE (TREE_TYPE (cval1));
-
- /* We can't just pass T to eval_subst in case cval1 or cval2
- was the same as ARG1. */
-
- tree high_result
- = fold_build2 (code, type,
- eval_subst (arg0, cval1, maxval,
- cval2, minval),
- arg1);
- tree equal_result
- = fold_build2 (code, type,
- eval_subst (arg0, cval1, maxval,
- cval2, maxval),
- arg1);
- tree low_result
- = fold_build2 (code, type,
- eval_subst (arg0, cval1, minval,
- cval2, maxval),
- arg1);
-
- /* All three of these results should be 0 or 1. Confirm they
- are. Then use those values to select the proper code
- to use. */
-
- if ((integer_zerop (high_result)
- || integer_onep (high_result))
- && (integer_zerop (equal_result)
- || integer_onep (equal_result))
- && (integer_zerop (low_result)
- || integer_onep (low_result)))
- {
- /* Make a 3-bit mask with the high-order bit being the
- value for `>', the next for '=', and the low for '<'. */
- switch ((integer_onep (high_result) * 4)
- + (integer_onep (equal_result) * 2)
- + integer_onep (low_result))
- {
- case 0:
- /* Always false. */
- return omit_one_operand (type, integer_zero_node, arg0);
- case 1:
- code = LT_EXPR;
- break;
- case 2:
- code = EQ_EXPR;
- break;
- case 3:
- code = LE_EXPR;
- break;
- case 4:
- code = GT_EXPR;
- break;
- case 5:
- code = NE_EXPR;
- break;
- case 6:
- code = GE_EXPR;
- break;
- case 7:
- /* Always true. */
- return omit_one_operand (type, integer_one_node, arg0);
- }
-
- if (save_p)
- return save_expr (build2 (code, type, cval1, cval2));
- else
- return fold_build2 (code, type, cval1, cval2);
- }
- }
- }
-
- /* If this is a comparison of a field, we may be able to simplify it. */
- if (((TREE_CODE (arg0) == COMPONENT_REF
- && lang_hooks.can_use_bit_fields_p ())
- || TREE_CODE (arg0) == BIT_FIELD_REF)
- && (code == EQ_EXPR || code == NE_EXPR)
- /* Handle the constant case even without -O
- to make sure the warnings are given. */
- && (optimize || TREE_CODE (arg1) == INTEGER_CST))
- {
- t1 = optimize_bit_field_compare (code, type, arg0, arg1);
- if (t1)
- return t1;
- }
-
- /* Fold a comparison of the address of COMPONENT_REFs with the same
- type and component to a comparison of the address of the base
- object. In short, &x->a OP &y->a to x OP y and
- &x->a OP &y.a to x OP &y */
- if (TREE_CODE (arg0) == ADDR_EXPR
- && TREE_CODE (TREE_OPERAND (arg0, 0)) == COMPONENT_REF
- && TREE_CODE (arg1) == ADDR_EXPR
- && TREE_CODE (TREE_OPERAND (arg1, 0)) == COMPONENT_REF)
- {
- tree cref0 = TREE_OPERAND (arg0, 0);
- tree cref1 = TREE_OPERAND (arg1, 0);
- if (TREE_OPERAND (cref0, 1) == TREE_OPERAND (cref1, 1))
- {
- tree op0 = TREE_OPERAND (cref0, 0);
- tree op1 = TREE_OPERAND (cref1, 0);
- return fold_build2 (code, type,
- build_fold_addr_expr (op0),
- build_fold_addr_expr (op1));
- }
- }
-
- /* Optimize comparisons of strlen vs zero to a compare of the
- first character of the string vs zero. To wit,
- strlen(ptr) == 0 => *ptr == 0
- strlen(ptr) != 0 => *ptr != 0
- Other cases should reduce to one of these two (or a constant)
- due to the return value of strlen being unsigned. */
- if ((code == EQ_EXPR || code == NE_EXPR)
- && integer_zerop (arg1)
- && TREE_CODE (arg0) == CALL_EXPR)
- {
- tree fndecl = get_callee_fndecl (arg0);
- tree arglist;
-
- if (fndecl
- && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
- && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_STRLEN
- && (arglist = TREE_OPERAND (arg0, 1))
- && TREE_CODE (TREE_TYPE (TREE_VALUE (arglist))) == POINTER_TYPE
- && ! TREE_CHAIN (arglist))
- {
- tree iref = build_fold_indirect_ref (TREE_VALUE (arglist));
- return fold_build2 (code, type, iref,
- build_int_cst (TREE_TYPE (iref), 0));
- }
- }
-
- /* We can fold X/C1 op C2 where C1 and C2 are integer constants
- into a single range test. */
- if ((TREE_CODE (arg0) == TRUNC_DIV_EXPR
- || TREE_CODE (arg0) == EXACT_DIV_EXPR)
- && TREE_CODE (arg1) == INTEGER_CST
- && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
- && !integer_zerop (TREE_OPERAND (arg0, 1))
- && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1))
- && !TREE_OVERFLOW (arg1))
- {
- t1 = fold_div_compare (code, type, arg0, arg1);
- if (t1 != NULL_TREE)
- return t1;
- }
-
- if ((code == EQ_EXPR || code == NE_EXPR)
- && integer_zerop (arg1)
- && tree_expr_nonzero_p (arg0))
- {
- tree res = constant_boolean_node (code==NE_EXPR, type);
- return omit_one_operand (type, res, arg0);
- }
-
- t1 = fold_relational_const (code, type, arg0, arg1);
- return t1 == NULL_TREE ? NULL_TREE : t1;
+ return NULL_TREE;
case UNORDERED_EXPR:
case ORDERED_EXPR:
TREE_OPERAND (arg0, 1))
&& !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (op2))))
{
- tem = invert_truthvalue (arg0);
- if (COMPARISON_CLASS_P (tem))
+ tem = fold_truth_not_expr (arg0);
+ if (tem && COMPARISON_CLASS_P (tem))
{
tem = fold_cond_expr_with_comparison (type, tem, op2, op1);
if (tem)
/* See if this can be inverted. If it can't, possibly because
it was a floating-point inequality comparison, don't do
anything. */
- tem = invert_truthvalue (arg0);
-
- if (TREE_CODE (tem) != TRUTH_NOT_EXPR)
+ tem = fold_truth_not_expr (arg0);
+ if (tem)
return fold_build3 (code, type, tem, op2, op1);
}
&& integer_zerop (TREE_OPERAND (arg0, 1))
&& integer_zerop (op2)
&& (tem = sign_bit_p (TREE_OPERAND (arg0, 0), arg1)))
- return fold_convert (type, fold_build2 (BIT_AND_EXPR,
- TREE_TYPE (tem), tem, arg1));
+ return fold_convert (type,
+ fold_build2 (BIT_AND_EXPR,
+ TREE_TYPE (tem), tem,
+ fold_convert (TREE_TYPE (tem), arg1)));
/* (A >> N) & 1 ? (1 << N) : 0 is simply A & (1 << N). A & 1 was
already handled above. */
if (integer_zerop (op2)
&& truth_value_p (TREE_CODE (arg0))
&& truth_value_p (TREE_CODE (arg1)))
- return fold_build2 (TRUTH_ANDIF_EXPR, type, arg0, arg1);
+ return fold_build2 (TRUTH_ANDIF_EXPR, type,
+ fold_convert (type, arg0),
+ arg1);
/* Convert A ? B : 1 into !A || B if A and B are truth values. */
if (integer_onep (op2)
&& truth_value_p (TREE_CODE (arg1)))
{
/* Only perform transformation if ARG0 is easily inverted. */
- tem = invert_truthvalue (arg0);
- if (TREE_CODE (tem) != TRUTH_NOT_EXPR)
- return fold_build2 (TRUTH_ORIF_EXPR, type, tem, arg1);
+ tem = fold_truth_not_expr (arg0);
+ if (tem)
+ return fold_build2 (TRUTH_ORIF_EXPR, type,
+ fold_convert (type, tem),
+ arg1);
}
/* Convert A ? 0 : B into !A && B if A and B are truth values. */
&& truth_value_p (TREE_CODE (op2)))
{
/* Only perform transformation if ARG0 is easily inverted. */
- tem = invert_truthvalue (arg0);
- if (TREE_CODE (tem) != TRUTH_NOT_EXPR)
- return fold_build2 (TRUTH_ANDIF_EXPR, type, tem, op2);
+ tem = fold_truth_not_expr (arg0);
+ if (tem)
+ return fold_build2 (TRUTH_ANDIF_EXPR, type,
+ fold_convert (type, tem),
+ op2);
}
/* Convert A ? 1 : B into A || B if A and B are truth values. */
if (integer_onep (arg1)
&& truth_value_p (TREE_CODE (arg0))
&& truth_value_p (TREE_CODE (op2)))
- return fold_build2 (TRUTH_ORIF_EXPR, type, arg0, op2);
+ return fold_build2 (TRUTH_ORIF_EXPR, type,
+ fold_convert (type, arg0),
+ op2);
return NULL_TREE;
{
void **slot;
enum tree_code code;
- char buf[sizeof (struct tree_function_decl)];
+ struct tree_function_decl buf;
int i, len;
recursive_label:
&& DECL_ASSEMBLER_NAME_SET_P (expr))
{
/* Allow DECL_ASSEMBLER_NAME to be modified. */
- memcpy (buf, expr, tree_size (expr));
- expr = (tree) buf;
+ memcpy ((char *) &buf, expr, tree_size (expr));
+ expr = (tree) &buf;
SET_DECL_ASSEMBLER_NAME (expr, NULL);
}
else if (TREE_CODE_CLASS (code) == tcc_type
|| TYPE_CONTAINS_PLACEHOLDER_INTERNAL (expr)))
{
/* Allow these fields to be modified. */
- memcpy (buf, expr, tree_size (expr));
- expr = (tree) buf;
+ memcpy ((char *) &buf, expr, tree_size (expr));
+ expr = (tree) &buf;
TYPE_CONTAINS_PLACEHOLDER_INTERNAL (expr) = 0;
TYPE_POINTER_TO (expr) = NULL;
TYPE_REFERENCE_TO (expr) = NULL;
int saved_trapping_math = flag_trapping_math;\
int saved_rounding_math = flag_rounding_math;\
int saved_trapv = flag_trapv;\
+ int saved_folding_initializer = folding_initializer;\
flag_signaling_nans = 0;\
flag_trapping_math = 0;\
flag_rounding_math = 0;\
- flag_trapv = 0
+ flag_trapv = 0;\
+ folding_initializer = 1;
#define END_FOLD_INIT \
flag_signaling_nans = saved_signaling_nans;\
flag_trapping_math = saved_trapping_math;\
flag_rounding_math = saved_rounding_math;\
- flag_trapv = saved_trapv
+ flag_trapv = saved_trapv;\
+ folding_initializer = saved_folding_initializer;
tree
fold_build1_initializer (enum tree_code code, tree type, tree op)
int
tree_expr_nonnegative_p (tree t)
{
+ if (t == error_mark_node)
+ return 0;
+
if (TYPE_UNSIGNED (TREE_TYPE (t)))
return 1;
switch (TREE_CODE (t))
{
+ case SSA_NAME:
+ /* Query VRP to see if it has recorded any information about
+ the range of this object. */
+ return ssa_name_nonnegative_p (t);
+
case ABS_EXPR:
/* We can't return 1 if flag_wrapv is set because
ABS_EXPR<INT_MIN> = INT_MIN. */
switch (TREE_CODE (t))
{
+ case SSA_NAME:
+ /* Query VRP to see if it has recorded any information about
+ the range of this object. */
+ return ssa_name_nonzero_p (t);
+
case ABS_EXPR:
return tree_expr_nonzero_p (TREE_OPERAND (t, 0));
tree inner_type = TREE_TYPE (TREE_OPERAND (t, 0));
tree outer_type = TREE_TYPE (t);
- return (TYPE_PRECISION (inner_type) >= TYPE_PRECISION (outer_type)
+ return (TYPE_PRECISION (outer_type) >= TYPE_PRECISION (inner_type)
&& tree_expr_nonzero_p (TREE_OPERAND (t, 0)));
}
break;
}
if (string
- && TREE_TYPE (exp) == TREE_TYPE (TREE_TYPE (string))
+ && TYPE_MODE (TREE_TYPE (exp)) == TYPE_MODE (TREE_TYPE (TREE_TYPE (string)))
&& TREE_CODE (string) == STRING_CST
&& TREE_CODE (index) == INTEGER_CST
&& compare_tree_int (index, TREE_STRING_LENGTH (string)) < 0
min_val = TYPE_MIN_VALUE (type_domain);
return build4 (ARRAY_REF, type, op, min_val, NULL_TREE, NULL_TREE);
}
+ /* *(foo *)&complexfoo => __real__ complexfoo */
+ else if (TREE_CODE (optype) == COMPLEX_TYPE
+ && type == TREE_TYPE (optype))
+ return fold_build1 (REALPART_EXPR, type, op);
}
+ /* ((foo*)&complexfoo)[1] => __imag__ complexfoo */
+ if (TREE_CODE (sub) == PLUS_EXPR
+ && TREE_CODE (TREE_OPERAND (sub, 1)) == INTEGER_CST)
+ {
+ tree op00 = TREE_OPERAND (sub, 0);
+ tree op01 = TREE_OPERAND (sub, 1);
+ tree op00type;
+
+ STRIP_NOPS (op00);
+ op00type = TREE_TYPE (op00);
+ if (TREE_CODE (op00) == ADDR_EXPR
+ && TREE_CODE (TREE_TYPE (op00type)) == COMPLEX_TYPE
+ && type == TREE_TYPE (TREE_TYPE (op00type)))
+ {
+ tree size = TYPE_SIZE_UNIT (type);
+ if (tree_int_cst_equal (size, op01))
+ return fold_build1 (IMAGPART_EXPR, type, TREE_OPERAND (op00, 0));
+ }
+ }
+
/* *(foo *)fooarrptr => (*fooarrptr)[0] */
if (TREE_CODE (TREE_TYPE (subtype)) == ARRAY_TYPE
&& type == TREE_TYPE (TREE_TYPE (subtype)))
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