/* 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 Free Software Foundation, Inc.
+ Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
+ 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
This file is part of GCC.
#include "config.h"
#include "system.h"
+#include "coretypes.h"
+#include "tm.h"
#include "flags.h"
#include "tree.h"
+#include "real.h"
#include "rtl.h"
#include "expr.h"
#include "tm_p.h"
static void decode PARAMS ((HOST_WIDE_INT *,
unsigned HOST_WIDE_INT *,
HOST_WIDE_INT *));
+static bool negate_expr_p PARAMS ((tree));
static tree negate_expr PARAMS ((tree));
static tree split_tree PARAMS ((tree, enum tree_code, tree *, tree *,
- int));
+ tree *, int));
static tree associate_trees PARAMS ((tree, tree, enum tree_code, tree));
static tree int_const_binop PARAMS ((enum tree_code, tree, tree, int));
static tree const_binop PARAMS ((enum tree_code, tree, tree, int));
static tree fold_convert PARAMS ((tree, tree));
static enum tree_code invert_tree_comparison PARAMS ((enum tree_code));
static enum tree_code swap_tree_comparison PARAMS ((enum tree_code));
+static int comparison_to_compcode PARAMS ((enum tree_code));
+static enum tree_code compcode_to_comparison PARAMS ((int));
static int truth_value_p PARAMS ((enum tree_code));
static int operand_equal_for_comparison_p PARAMS ((tree, tree, tree));
static int twoval_comparison_p PARAMS ((tree, tree *, tree *, int *));
static tree eval_subst PARAMS ((tree, tree, tree, tree, tree));
-static tree omit_one_operand PARAMS ((tree, tree, tree));
static tree pedantic_omit_one_operand PARAMS ((tree, tree, tree));
static tree distribute_bit_expr PARAMS ((enum tree_code, tree, tree, tree));
static tree make_bit_field_ref PARAMS ((tree, tree, int, int, int));
enum machine_mode *, int *,
int *, tree *, tree *));
static int all_ones_mask_p PARAMS ((tree, int));
+static tree sign_bit_p PARAMS ((tree, tree));
static int simple_operand_p PARAMS ((tree));
static tree range_binop PARAMS ((enum tree_code, tree, tree, int,
tree, int));
static tree fold_truthop PARAMS ((enum tree_code, tree, tree, tree));
static tree optimize_minmax_comparison PARAMS ((tree));
static tree extract_muldiv PARAMS ((tree, tree, enum tree_code, tree));
+static tree extract_muldiv_1 PARAMS ((tree, tree, enum tree_code, tree));
static tree strip_compound_expr PARAMS ((tree, tree));
static int multiple_of_p PARAMS ((tree, tree, tree));
static tree constant_boolean_node PARAMS ((int, tree));
static int count_cond PARAMS ((tree, int));
-static tree fold_binary_op_with_conditional_arg
+static tree fold_binary_op_with_conditional_arg
PARAMS ((enum tree_code, tree, tree, tree, int));
static bool fold_real_zero_addition_p PARAMS ((tree, tree, int));
-
-#ifndef BRANCH_COST
-#define BRANCH_COST 1
-#endif
-
-#if defined(HOST_EBCDIC)
-/* bit 8 is significant in EBCDIC */
-#define CHARMASK 0xff
-#else
-#define CHARMASK 0x7f
-#endif
+static tree fold_mathfn_compare PARAMS ((enum built_in_function,
+ enum tree_code, tree, tree, tree));
+static tree fold_inf_compare PARAMS ((enum tree_code, tree, tree, tree));
+
+/* 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. */
+#define COMPCODE_FALSE 0
+#define COMPCODE_LT 1
+#define COMPCODE_EQ 2
+#define COMPCODE_LE 3
+#define COMPCODE_GT 4
+#define COMPCODE_NE 5
+#define COMPCODE_GE 6
+#define COMPCODE_TRUE 7
/* 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,
Return 1 if a signed overflow occurs, 0 otherwise. If OVERFLOW is
nonzero, a signed overflow has already occurred in calculating T, so
- propagate it.
-
- Make the real constant T valid for its type by calling CHECK_FLOAT_VALUE,
- if it exists. */
+ propagate it. */
int
force_fit_type (t, overflow)
if (TREE_CODE (t) == REAL_CST)
{
-#ifdef CHECK_FLOAT_VALUE
- CHECK_FLOAT_VALUE (TYPE_MODE (TREE_TYPE (t)), TREE_REAL_CST (t),
- overflow);
-#endif
+ /* ??? Used to check for overflow here via CHECK_FLOAT_TYPE.
+ Consider doing it via real_convert now. */
return overflow;
}
/* Sign extend all bits that are beyond the precision. */
signmask = -((prec > HOST_BITS_PER_WIDE_INT
- ? (*hv >> (prec - HOST_BITS_PER_WIDE_INT - 1))
+ ? ((unsigned HOST_WIDE_INT) *hv
+ >> (prec - HOST_BITS_PER_WIDE_INT - 1))
: (*lv >> (prec - 1))) & 1);
if (prec >= 2 * HOST_BITS_PER_WIDE_INT)
int num_hi_sig, den_hi_sig;
unsigned HOST_WIDE_INT quo_est, scale;
- /* Find the highest non-zero divisor digit. */
+ /* Find the highest nonzero divisor digit. */
for (i = 4 - 1;; i--)
if (den[i] != 0)
{
/* If quo_est was high by one, then num[i] went negative and
we need to correct things. */
- if (num[num_hi_sig] < carry)
+ if (num[num_hi_sig] < (HOST_WIDE_INT) carry)
{
quo_est--;
carry = 0; /* add divisor back in */
return overflow;
}
\f
+/* Determine whether an expression T can be cheaply negated using
+ the function negate_expr. */
+
+static bool
+negate_expr_p (t)
+ tree t;
+{
+ unsigned HOST_WIDE_INT val;
+ unsigned int prec;
+ tree type;
+
+ if (t == 0)
+ return false;
+
+ type = TREE_TYPE (t);
+
+ STRIP_SIGN_NOPS (t);
+ switch (TREE_CODE (t))
+ {
+ case INTEGER_CST:
+ if (TREE_UNSIGNED (type))
+ return false;
+
+ /* Check that -CST will not overflow type. */
+ prec = TYPE_PRECISION (type);
+ if (prec > HOST_BITS_PER_WIDE_INT)
+ {
+ if (TREE_INT_CST_LOW (t) != 0)
+ return true;
+ prec -= HOST_BITS_PER_WIDE_INT;
+ val = TREE_INT_CST_HIGH (t);
+ }
+ else
+ val = TREE_INT_CST_LOW (t);
+ if (prec < HOST_BITS_PER_WIDE_INT)
+ val &= ((unsigned HOST_WIDE_INT) 1 << prec) - 1;
+ return val != ((unsigned HOST_WIDE_INT) 1 << (prec - 1));
+
+ case REAL_CST:
+ case NEGATE_EXPR:
+ case MINUS_EXPR:
+ return true;
+
+ default:
+ break;
+ }
+ return false;
+}
+
/* Given T, an expression, return the negation of T. Allow for T to be
null, in which case return null. */
combined with CODE to make IN. "constant" means an expression with
TREE_CONSTANT but that isn't an actual constant. CODE must be a
commutative arithmetic operation. Store the constant part into *CONP,
- the literal in &LITP and return the variable part. If a part isn't
+ the literal in *LITP and return the variable part. If a part isn't
present, set it to null. If the tree does not decompose in this way,
return the entire tree as the variable part and the other parts as null.
If CODE is PLUS_EXPR we also split trees that use MINUS_EXPR. In that
- case, we negate an operand that was subtracted. If NEGATE_P is true, we
- are negating all of IN.
+ case, we negate an operand that was subtracted. Except if it is a
+ literal for which we use *MINUS_LITP instead.
+
+ If NEGATE_P is true, we are negating all of IN, again except a literal
+ for which we use *MINUS_LITP instead.
If IN is itself a literal or constant, return it as appropriate.
same type as IN, but they will have the same signedness and mode. */
static tree
-split_tree (in, code, conp, litp, negate_p)
+split_tree (in, code, conp, litp, minus_litp, negate_p)
tree in;
enum tree_code code;
- tree *conp, *litp;
+ tree *conp, *litp, *minus_litp;
int negate_p;
{
tree var = 0;
*conp = 0;
*litp = 0;
+ *minus_litp = 0;
/* Strip any conversions that don't change the machine mode or signedness. */
STRIP_SIGN_NOPS (in);
var = op1, neg_var_p = neg1_p;
/* Now do any needed negations. */
- if (neg_litp_p) *litp = negate_expr (*litp);
- if (neg_conp_p) *conp = negate_expr (*conp);
- if (neg_var_p) var = negate_expr (var);
+ if (neg_litp_p)
+ *minus_litp = *litp, *litp = 0;
+ if (neg_conp_p)
+ *conp = negate_expr (*conp);
+ if (neg_var_p)
+ var = negate_expr (var);
}
else if (TREE_CONSTANT (in))
*conp = in;
if (negate_p)
{
- var = negate_expr (var);
+ if (*litp)
+ *minus_litp = *litp, *litp = 0;
+ else if (*minus_litp)
+ *litp = *minus_litp, *minus_litp = 0;
*conp = negate_expr (*conp);
- *litp = negate_expr (*litp);
+ var = negate_expr (var);
}
return var;
/* Re-associate trees split by the above function. T1 and T2 are either
expressions to associate or null. Return the new expression, if any. If
- we build an operation, do it in TYPE and with CODE, except if CODE is a
- MINUS_EXPR, in which case we use PLUS_EXPR since split_tree will already
- have taken care of the negations. */
+ we build an operation, do it in TYPE and with CODE. */
static tree
associate_trees (t1, t2, code, type)
else if (t2 == 0)
return t1;
- if (code == MINUS_EXPR)
- code = PLUS_EXPR;
-
/* If either input is CODE, a PLUS_EXPR, or a MINUS_EXPR, don't
try to fold this since we will have infinite recursion. But do
deal with any NEGATE_EXPRs. */
if (TREE_CODE (t1) == code || TREE_CODE (t2) == code
|| TREE_CODE (t1) == MINUS_EXPR || TREE_CODE (t2) == MINUS_EXPR)
{
- if (TREE_CODE (t1) == NEGATE_EXPR)
- return build (MINUS_EXPR, type, convert (type, t2),
- convert (type, TREE_OPERAND (t1, 0)));
- else if (TREE_CODE (t2) == NEGATE_EXPR)
- return build (MINUS_EXPR, type, convert (type, t1),
- convert (type, TREE_OPERAND (t2, 0)));
- else
- return build (code, type, convert (type, t1), convert (type, t2));
+ if (code == PLUS_EXPR)
+ {
+ if (TREE_CODE (t1) == NEGATE_EXPR)
+ return build (MINUS_EXPR, type, convert (type, t2),
+ convert (type, TREE_OPERAND (t1, 0)));
+ else if (TREE_CODE (t2) == NEGATE_EXPR)
+ return build (MINUS_EXPR, type, convert (type, t1),
+ convert (type, TREE_OPERAND (t2, 0)));
+ }
+ return build (code, type, convert (type, t1), convert (type, t2));
}
return fold (build (code, type, convert (type, t1), convert (type, t2)));
tree t = (tree) x;
return (TREE_INT_CST_HIGH (t) ^ TREE_INT_CST_LOW (t)
- ^ (hashval_t) ((long) TREE_TYPE (t) >> 3)
+ ^ htab_hash_pointer (TREE_TYPE (t))
^ (TREE_OVERFLOW (t) << 20));
}
-/* Return non-zero if the value represented by *X (an INTEGER_CST tree node)
+/* Return nonzero if the value represented by *X (an INTEGER_CST tree node)
is the same as that given by *Y, which is the same. */
static int
/* Likewise, but the desired type is specified explicitly. */
+static GTY (()) tree new_const;
+static GTY ((if_marked ("ggc_marked_p"), param_is (union tree_node)))
+ htab_t size_htab;
+
tree
size_int_type_wide (number, type)
HOST_WIDE_INT number;
tree type;
{
- static htab_t size_htab = 0;
- static tree new_const = 0;
PTR *slot;
if (size_htab == 0)
{
- size_htab = htab_create (1024, size_htab_hash, size_htab_eq, NULL);
- ggc_add_deletable_htab (size_htab, NULL, NULL);
+ size_htab = htab_create_ggc (1024, size_htab_hash, size_htab_eq, NULL);
new_const = make_node (INTEGER_CST);
- ggc_add_tree_root (&new_const, 1);
}
/* Adjust NEW_CONST to be the constant we want. If it's already in the
{
if (REAL_VALUE_ISNAN (TREE_REAL_CST (arg1)))
{
- t = arg1;
- TREE_TYPE (arg1) = type;
+ /* We make a copy of ARG1 so that we don't modify an
+ existing constant tree. */
+ t = copy_node (arg1);
+ TREE_TYPE (t) = type;
return t;
}
}
}
+
+/* Convert a comparison tree code from an enum tree_code representation
+ into a compcode bit-based encoding. This function is the inverse of
+ compcode_to_comparison. */
+
+static int
+comparison_to_compcode (code)
+ enum tree_code code;
+{
+ switch (code)
+ {
+ case LT_EXPR:
+ return COMPCODE_LT;
+ case EQ_EXPR:
+ return COMPCODE_EQ;
+ case LE_EXPR:
+ return COMPCODE_LE;
+ case GT_EXPR:
+ return COMPCODE_GT;
+ case NE_EXPR:
+ return COMPCODE_NE;
+ case GE_EXPR:
+ return COMPCODE_GE;
+ default:
+ abort ();
+ }
+}
+
+/* Convert a compcode bit-based encoding of a comparison operator back
+ to GCC's enum tree_code representation. This function is the
+ inverse of comparison_to_compcode. */
+
+static enum tree_code
+compcode_to_comparison (code)
+ int code;
+{
+ switch (code)
+ {
+ case COMPCODE_LT:
+ return LT_EXPR;
+ case COMPCODE_EQ:
+ return EQ_EXPR;
+ case COMPCODE_LE:
+ return LE_EXPR;
+ case COMPCODE_GT:
+ return GT_EXPR;
+ case COMPCODE_NE:
+ return NE_EXPR;
+ case COMPCODE_GE:
+ return GE_EXPR;
+ default:
+ abort ();
+ }
+}
+
/* Return nonzero if CODE is a tree code that represents a truth value. */
static int
}
\f
/* Return nonzero if two operands are necessarily equal.
- If ONLY_CONST is non-zero, only return non-zero for constants.
+ If ONLY_CONST is nonzero, only return nonzero for constants.
This function tests whether the operands are indistinguishable;
it does not test whether they are equal using C's == operation.
The distinction is important for IEEE floating point, because
/* Make sure shorter operand is extended the right way
to match the longer operand. */
- primarg1 = convert (signed_or_unsigned_type (unsignedp1,
- TREE_TYPE (primarg1)),
- primarg1);
+ primarg1 = convert ((*lang_hooks.types.signed_or_unsigned_type)
+ (unsignedp1, TREE_TYPE (primarg1)), primarg1);
if (operand_equal_p (arg0, convert (type, primarg1), 0))
return 1;
/* See if ARG is an expression that is either a comparison or is performing
arithmetic on comparisons. The comparisons must only be comparing
two different values, which will be stored in *CVAL1 and *CVAL2; if
- they are non-zero it means that some operands have already been found.
+ they are nonzero it means that some operands have already been found.
No variables may be used anywhere else in the expression except in the
comparisons. If SAVE_P is true it means we removed a SAVE_EXPR around
the expression and save_expr needs to be called with CVAL1 and CVAL2.
If OMITTED has side effects, we must evaluate it. Otherwise, just do
the conversion of RESULT to TYPE. */
-static tree
+tree
omit_one_operand (type, result, omitted)
tree type, result, omitted;
{
{
if (FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (arg, 0)))
&& !flag_unsafe_math_optimizations
- && code != NE_EXPR
+ && code != NE_EXPR
&& code != EQ_EXPR)
return build1 (TRUTH_NOT_EXPR, type, arg);
else
}
\f
/* Return a BIT_FIELD_REF of type TYPE to refer to BITSIZE bits of INNER
- starting at BITPOS. The field is unsigned if UNSIGNEDP is non-zero. */
+ starting at BITPOS. The field is unsigned if UNSIGNEDP is nonzero. */
static tree
make_bit_field_ref (inner, type, bitsize, bitpos, unsignedp)
/* Set signed and unsigned types of the precision of this mode for the
shifts below. */
- signed_type = type_for_mode (nmode, 0);
- unsigned_type = type_for_mode (nmode, 1);
+ signed_type = (*lang_hooks.types.type_for_mode) (nmode, 0);
+ unsigned_type = (*lang_hooks.types.type_for_mode) (nmode, 1);
/* Compute the bit position and size for the new reference and our offset
within it. If the new reference is the same size as the original, we
return 0;
/* Compute the mask to access the bitfield. */
- unsigned_type = type_for_size (*pbitsize, 1);
+ unsigned_type = (*lang_hooks.types.type_for_size) (*pbitsize, 1);
precision = TYPE_PRECISION (unsigned_type);
mask = build_int_2 (~0, ~0);
return inner;
}
-/* Return non-zero if MASK represents a mask of SIZE ones in the low-order
+/* Return nonzero if MASK represents a mask of SIZE ones in the low-order
bit positions. */
static int
tree tmask;
tmask = build_int_2 (~0, ~0);
- TREE_TYPE (tmask) = signed_type (type);
+ TREE_TYPE (tmask) = (*lang_hooks.types.signed_type) (type);
force_fit_type (tmask, 0);
return
tree_int_cst_equal (mask,
size_int (precision - size), 0));
}
+/* Subroutine for fold: determine if VAL is the INTEGER_CONST that
+ represents the sign bit of EXP's type. If EXP represents a sign
+ or zero extension, also test VAL against the unextended type.
+ The return value is the (sub)expression whose sign bit is VAL,
+ or NULL_TREE otherwise. */
+
+static tree
+sign_bit_p (exp, val)
+ tree exp;
+ tree val;
+{
+ unsigned HOST_WIDE_INT lo;
+ HOST_WIDE_INT hi;
+ int width;
+ tree t;
+
+ /* Tree EXP must have an integral type. */
+ t = TREE_TYPE (exp);
+ if (! INTEGRAL_TYPE_P (t))
+ return NULL_TREE;
+
+ /* Tree VAL must be an integer constant. */
+ if (TREE_CODE (val) != INTEGER_CST
+ || TREE_CONSTANT_OVERFLOW (val))
+ return NULL_TREE;
+
+ width = TYPE_PRECISION (t);
+ if (width > HOST_BITS_PER_WIDE_INT)
+ {
+ hi = (unsigned HOST_WIDE_INT) 1 << (width - HOST_BITS_PER_WIDE_INT - 1);
+ lo = 0;
+ }
+ else
+ {
+ hi = 0;
+ lo = (unsigned HOST_WIDE_INT) 1 << (width - 1);
+ }
+
+ if (TREE_INT_CST_HIGH (val) == hi && TREE_INT_CST_LOW (val) == lo)
+ return exp;
+
+ /* Handle extension from a narrower type. */
+ if (TREE_CODE (exp) == NOP_EXPR
+ && TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (exp, 0))) < width)
+ return sign_bit_p (TREE_OPERAND (exp, 0), val);
+
+ return NULL_TREE;
+}
+
/* Subroutine for fold_truthop: determine if an operand is simple enough
to be evaluated unconditionally. */
be interpreted as positive. */
if (TREE_UNSIGNED (type) && ! TREE_UNSIGNED (TREE_TYPE (exp)))
{
- tree equiv_type = type_for_mode (TYPE_MODE (type), 1);
+ tree equiv_type = (*lang_hooks.types.type_for_mode)
+ (TYPE_MODE (type), 1);
tree high_positive;
/* A range without an upper bound is, naturally, unbounded.
= TYPE_MAX_VALUE (equiv_type) ? TYPE_MAX_VALUE (equiv_type)
: TYPE_MAX_VALUE (type);
- high_positive = fold (build (RSHIFT_EXPR, type,
- convert (type, high_positive),
- convert (type, integer_one_node)));
+ if (TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (exp)))
+ high_positive = fold (build (RSHIFT_EXPR, type,
+ convert (type, high_positive),
+ convert (type, integer_one_node)));
/* If the low bound is specified, "and" the range with the
range for which the original unsigned value will be
tree low, high;
{
tree etype = TREE_TYPE (exp);
- tree utype, value;
+ tree value;
if (! in_p
&& (0 != (value = build_range_check (type, exp, 1, low, high))))
return invert_truthvalue (value);
- else if (low == 0 && high == 0)
+ if (low == 0 && high == 0)
return convert (type, integer_one_node);
- else if (low == 0)
+ if (low == 0)
return fold (build (LE_EXPR, type, exp, high));
- else if (high == 0)
+ if (high == 0)
return fold (build (GE_EXPR, type, exp, low));
- else if (operand_equal_p (low, high, 0))
+ if (operand_equal_p (low, high, 0))
return fold (build (EQ_EXPR, type, exp, low));
- else if (TREE_UNSIGNED (etype) && integer_zerop (low))
- return build_range_check (type, exp, 1, 0, high);
+ if (integer_zerop (low))
+ {
+ if (! TREE_UNSIGNED (etype))
+ {
+ etype = (*lang_hooks.types.unsigned_type) (etype);
+ high = convert (etype, high);
+ exp = convert (etype, exp);
+ }
+ return build_range_check (type, exp, 1, 0, high);
+ }
- else if (integer_zerop (low))
+ /* Optimize (c>=1) && (c<=127) into (signed char)c > 0. */
+ if (integer_onep (low) && TREE_CODE (high) == INTEGER_CST)
{
- utype = unsigned_type (etype);
- return build_range_check (type, convert (utype, exp), 1, 0,
- convert (utype, high));
+ unsigned HOST_WIDE_INT lo;
+ HOST_WIDE_INT hi;
+ int prec;
+
+ prec = TYPE_PRECISION (etype);
+ if (prec <= HOST_BITS_PER_WIDE_INT)
+ {
+ hi = 0;
+ lo = ((unsigned HOST_WIDE_INT) 1 << (prec - 1)) - 1;
+ }
+ else
+ {
+ hi = ((HOST_WIDE_INT) 1 << (prec - HOST_BITS_PER_WIDE_INT - 1)) - 1;
+ lo = (unsigned HOST_WIDE_INT) -1;
+ }
+
+ if (TREE_INT_CST_HIGH (high) == hi && TREE_INT_CST_LOW (high) == lo)
+ {
+ if (TREE_UNSIGNED (etype))
+ {
+ etype = (*lang_hooks.types.signed_type) (etype);
+ exp = convert (etype, exp);
+ }
+ return fold (build (GT_EXPR, type, exp,
+ convert (etype, integer_zero_node)));
+ }
}
- else if (0 != (value = const_binop (MINUS_EXPR, high, low, 0))
- && ! TREE_OVERFLOW (value))
+ if (0 != (value = const_binop (MINUS_EXPR, high, low, 0))
+ && ! TREE_OVERFLOW (value))
return build_range_check (type,
fold (build (MINUS_EXPR, etype, exp, low)),
1, convert (etype, integer_zero_node), value);
- else
- return 0;
+
+ return 0;
}
\f
/* Given two ranges, see if we can merge them into one. Return 1 if we
zero or one, and the conversion to a signed type can never overflow.
We could get an overflow if this conversion is done anywhere else. */
if (TREE_UNSIGNED (type))
- temp = convert (signed_type (type), temp);
+ temp = convert ((*lang_hooks.types.signed_type) (type), temp);
temp = const_binop (LSHIFT_EXPR, temp, size_int (modesize - 1), 0);
temp = const_binop (RSHIFT_EXPR, temp, size_int (modesize - p - 1), 0);
rl_arg = TREE_OPERAND (rhs, 0);
rr_arg = TREE_OPERAND (rhs, 1);
+ /* Simplify (x<y) && (x==y) into (x<=y) and related optimizations. */
+ if (simple_operand_p (ll_arg)
+ && simple_operand_p (lr_arg)
+ && !FLOAT_TYPE_P (TREE_TYPE (ll_arg)))
+ {
+ int compcode;
+
+ if (operand_equal_p (ll_arg, rl_arg, 0)
+ && operand_equal_p (lr_arg, rr_arg, 0))
+ {
+ int lcompcode, rcompcode;
+
+ lcompcode = comparison_to_compcode (lcode);
+ rcompcode = comparison_to_compcode (rcode);
+ compcode = (code == TRUTH_AND_EXPR)
+ ? lcompcode & rcompcode
+ : lcompcode | rcompcode;
+ }
+ else if (operand_equal_p (ll_arg, rr_arg, 0)
+ && operand_equal_p (lr_arg, rl_arg, 0))
+ {
+ int lcompcode, rcompcode;
+
+ rcode = swap_tree_comparison (rcode);
+ lcompcode = comparison_to_compcode (lcode);
+ rcompcode = comparison_to_compcode (rcode);
+ compcode = (code == TRUTH_AND_EXPR)
+ ? lcompcode & rcompcode
+ : lcompcode | rcompcode;
+ }
+ else
+ compcode = -1;
+
+ if (compcode == COMPCODE_TRUE)
+ return convert (truth_type, integer_one_node);
+ else if (compcode == COMPCODE_FALSE)
+ return convert (truth_type, integer_zero_node);
+ else if (compcode != -1)
+ return build (compcode_to_comparison (compcode),
+ truth_type, ll_arg, lr_arg);
+ }
+
/* If the RHS can be evaluated unconditionally and its operands are
simple, it wins to evaluate the RHS unconditionally on machines
with expensive branches. In this case, this isn't a comparison
&& ! FLOAT_TYPE_P (TREE_TYPE (rl_arg))
&& simple_operand_p (rl_arg)
&& simple_operand_p (rr_arg))
- return build (code, truth_type, lhs, rhs);
+ {
+ /* Convert (a != 0) || (b != 0) into (a | b) != 0. */
+ if (code == TRUTH_OR_EXPR
+ && lcode == NE_EXPR && integer_zerop (lr_arg)
+ && rcode == NE_EXPR && integer_zerop (rr_arg)
+ && TREE_TYPE (ll_arg) == TREE_TYPE (rl_arg))
+ return build (NE_EXPR, truth_type,
+ build (BIT_IOR_EXPR, TREE_TYPE (ll_arg),
+ ll_arg, rl_arg),
+ integer_zero_node);
+
+ /* Convert (a == 0) && (b == 0) into (a | b) == 0. */
+ if (code == TRUTH_AND_EXPR
+ && lcode == EQ_EXPR && integer_zerop (lr_arg)
+ && rcode == EQ_EXPR && integer_zerop (rr_arg)
+ && TREE_TYPE (ll_arg) == TREE_TYPE (rl_arg))
+ return build (EQ_EXPR, truth_type,
+ build (BIT_IOR_EXPR, TREE_TYPE (ll_arg),
+ ll_arg, rl_arg),
+ integer_zero_node);
+
+ return build (code, truth_type, lhs, rhs);
+ }
/* See if the comparisons can be merged. Then get all the parameters for
each side. */
return 0;
}
+ /* After this point all optimizations will generate bit-field
+ references, which we might not want. */
+ if (! (*lang_hooks.can_use_bit_fields_p) ())
+ return 0;
+
/* See if we can find a mode that contains both fields being compared on
the left. If we can't, fail. Otherwise, update all constants and masks
to be relative to a field of that size. */
lnbitsize = GET_MODE_BITSIZE (lnmode);
lnbitpos = first_bit & ~ (lnbitsize - 1);
- lntype = type_for_size (lnbitsize, 1);
+ lntype = (*lang_hooks.types.type_for_size) (lnbitsize, 1);
xll_bitpos = ll_bitpos - lnbitpos, xrl_bitpos = rl_bitpos - lnbitpos;
if (BYTES_BIG_ENDIAN)
rnbitsize = GET_MODE_BITSIZE (rnmode);
rnbitpos = first_bit & ~ (rnbitsize - 1);
- rntype = type_for_size (rnbitsize, 1);
+ rntype = (*lang_hooks.types.type_for_size) (rnbitsize, 1);
xlr_bitpos = lr_bitpos - rnbitpos, xrr_bitpos = rr_bitpos - rnbitpos;
if (BYTES_BIG_ENDIAN)
other operations already in T. WIDE_TYPE, if non-null, is a type that
should be used for the computation if wider than our type.
- For example, if we are dividing (X * 8) + (Y + 16) by 4, we can return
- (X * 2) + (Y + 4). We must, however, be assured that either the original
+ For example, if we are dividing (X * 8) + (Y * 16) by 4, we can return
+ (X * 2) + (Y * 4). We must, however, be assured that either the original
expression would not overflow or that overflow is undefined for the type
in the language in question.
enum tree_code code;
tree wide_type;
{
+ /* To avoid exponential search depth, refuse to allow recursion past
+ three levels. Beyond that (1) it's highly unlikely that we'll find
+ something interesting and (2) we've probably processed it before
+ when we built the inner expression. */
+
+ static int depth;
+ tree ret;
+
+ if (depth > 3)
+ return NULL;
+
+ depth++;
+ ret = extract_muldiv_1 (t, c, code, wide_type);
+ depth--;
+
+ return ret;
+}
+
+static tree
+extract_muldiv_1 (t, c, code, wide_type)
+ tree t;
+ tree c;
+ enum tree_code code;
+ tree wide_type;
+{
tree type = TREE_TYPE (t);
enum tree_code tcode = TREE_CODE (t);
tree ctype = (wide_type != 0 && (GET_MODE_SIZE (TYPE_MODE (wide_type))
break;
case CONVERT_EXPR: case NON_LVALUE_EXPR: case NOP_EXPR:
- /* If op0 is an expression, and is unsigned, and the type is
- smaller than ctype, then we cannot widen the expression. */
+ /* If op0 is an expression ... */
if ((TREE_CODE_CLASS (TREE_CODE (op0)) == '<'
|| TREE_CODE_CLASS (TREE_CODE (op0)) == '1'
|| TREE_CODE_CLASS (TREE_CODE (op0)) == '2'
|| TREE_CODE_CLASS (TREE_CODE (op0)) == 'e')
- && TREE_UNSIGNED (TREE_TYPE (op0))
- && ! (TREE_CODE (TREE_TYPE (op0)) == INTEGER_TYPE
- && TYPE_IS_SIZETYPE (TREE_TYPE (op0)))
- && (GET_MODE_SIZE (TYPE_MODE (ctype))
- > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))))
+ /* ... and is unsigned, and its type is smaller than ctype,
+ then we cannot pass through as widening. */
+ && ((TREE_UNSIGNED (TREE_TYPE (op0))
+ && ! (TREE_CODE (TREE_TYPE (op0)) == INTEGER_TYPE
+ && TYPE_IS_SIZETYPE (TREE_TYPE (op0)))
+ && (GET_MODE_SIZE (TYPE_MODE (ctype))
+ > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))))
+ /* ... or its type is larger than ctype,
+ then we cannot pass through this truncation. */
+ || (GET_MODE_SIZE (TYPE_MODE (ctype))
+ < GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0))))
+ /* ... or signedness changes for division or modulus,
+ then we cannot pass through this conversion. */
+ || (code != MULT_EXPR
+ && (TREE_UNSIGNED (ctype)
+ != TREE_UNSIGNED (TREE_TYPE (op0))))))
break;
/* Pass the constant down and see if we can make a simplification. If
t2 = extract_muldiv (op1, c, code, wide_type);
if (t1 != 0 && t2 != 0
&& (code == MULT_EXPR
- /* If not multiplication, we can only do this if either operand
- is divisible by c. */
- || multiple_of_p (ctype, op0, c)
- || multiple_of_p (ctype, op1, c)))
+ /* If not multiplication, we can only do this if both operands
+ are divisible by c. */
+ || (multiple_of_p (ctype, op0, c)
+ && multiple_of_p (ctype, op1, c))))
return fold (build (tcode, ctype, convert (ctype, t1),
convert (ctype, t2)));
of our constant, do the operation and verify it doesn't overflow. */
if (code == MULT_EXPR
|| integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0)))
- {
- op1 = const_binop (code, convert (ctype, op1), convert (ctype, c), 0);
- if (op1 == 0 || TREE_OVERFLOW (op1))
- break;
- }
+ {
+ op1 = const_binop (code, convert (ctype, op1), convert (ctype, c), 0);
+ if (op1 == 0 || TREE_OVERFLOW (op1))
+ break;
+ }
else
- break;
+ break;
/* If we have an unsigned type is not a sizetype, we cannot widen
the operation since it will change the result if the original
if (type == integer_type_node)
return value ? integer_one_node : integer_zero_node;
else if (TREE_CODE (type) == BOOLEAN_TYPE)
- return truthvalue_conversion (value ? integer_one_node :
- integer_zero_node);
+ return (*lang_hooks.truthvalue_conversion) (value ? integer_one_node :
+ integer_zero_node);
else
{
tree t = build_int_2 (value, 0);
return MIN (lim, 1 + ctrue + cfalse);
}
-/* Transform `a + (b ? x : y)' into `x ? (a + b) : (a + y)'.
+/* Transform `a + (b ? x : y)' into `b ? (a + x) : (a + y)'.
Transform, `a + (x < y)' into `(x < y) ? (a + 1) : (a + 0)'. Here
CODE corresponds to the `+', COND to the `(b ? x : y)' or `(x < y)'
- expression, and ARG to `a'. If COND_FIRST_P is non-zero, then the
+ expression, and ARG to `a'. If COND_FIRST_P is nonzero, then the
COND is the first argument to CODE; otherwise (as in the example
given here), it is the second argument. TYPE is the type of the
original expression. */
/* And these are the types of the expressions. */
tree lhs_type = type;
tree rhs_type = type;
+ int save = 0;
if (cond_first_p)
{
we simply build `a, throw 3'. */
if (VOID_TYPE_P (TREE_TYPE (true_value)))
{
- lhs_code = COMPOUND_EXPR;
- if (!cond_first_p)
- lhs_type = void_type_node;
+ if (! cond_first_p)
+ {
+ lhs_code = COMPOUND_EXPR;
+ lhs_type = void_type_node;
+ }
+ else
+ lhs = true_value;
}
if (VOID_TYPE_P (TREE_TYPE (false_value)))
{
- rhs_code = COMPOUND_EXPR;
- if (!cond_first_p)
- rhs_type = void_type_node;
+ if (! cond_first_p)
+ {
+ rhs_code = COMPOUND_EXPR;
+ rhs_type = void_type_node;
+ }
+ else
+ rhs = false_value;
}
}
else
true_value = convert (testtype, integer_one_node);
false_value = convert (testtype, integer_zero_node);
}
-
+
/* If ARG is complex we want to make sure we only evaluate
it once. Though this is only required if it is volatile, it
might be more efficient even if it is not. However, if we
primarily to see if we do end up with constant and this
SAVE_EXPR interferes with later optimizations, suppressing
it when we can is important.
-
+
If we are not in a function, we can't make a SAVE_EXPR, so don't
try to do so. Don't try to see if the result is a constant
if an arm is a COND_EXPR since we get exponential behavior
in that case. */
-
- if (TREE_CODE (arg) != SAVE_EXPR && ! TREE_CONSTANT (arg)
- && (*lang_hooks.decls.global_bindings_p) () == 0
- && ((TREE_CODE (arg) != VAR_DECL
- && TREE_CODE (arg) != PARM_DECL)
- || TREE_SIDE_EFFECTS (arg)))
+
+ if (TREE_CODE (arg) == SAVE_EXPR)
+ save = 1;
+ else if (lhs == 0 && rhs == 0
+ && !TREE_CONSTANT (arg)
+ && (*lang_hooks.decls.global_bindings_p) () == 0
+ && ((TREE_CODE (arg) != VAR_DECL && TREE_CODE (arg) != PARM_DECL)
+ || TREE_SIDE_EFFECTS (arg)))
{
if (TREE_CODE (true_value) != COND_EXPR)
lhs = fold (build (lhs_code, lhs_type, *true_lhs, *true_rhs));
-
+
if (TREE_CODE (false_value) != COND_EXPR)
rhs = fold (build (rhs_code, rhs_type, *false_lhs, *false_rhs));
-
+
if ((lhs == 0 || ! TREE_CONSTANT (lhs))
&& (rhs == 0 || !TREE_CONSTANT (rhs)))
- arg = save_expr (arg), lhs = rhs = 0;
+ {
+ arg = save_expr (arg);
+ lhs = rhs = 0;
+ save = 1;
+ }
}
-
+
if (lhs == 0)
lhs = fold (build (lhs_code, lhs_type, *true_lhs, *true_rhs));
if (rhs == 0)
rhs = fold (build (rhs_code, rhs_type, *false_lhs, *false_rhs));
-
+
test = fold (build (COND_EXPR, type, test, lhs, rhs));
-
- if (TREE_CODE (arg) == SAVE_EXPR)
+
+ if (save)
return build (COMPOUND_EXPR, type,
convert (void_type_node, arg),
strip_compound_expr (test, arg));
TYPE, X + ADDEND is the same as X. If NEGATE, return true if X -
ADDEND is the same as X.
- X + 0 and X - 0 both give X when X is NaN, infinite, or non-zero
+ X + 0 and X - 0 both give X when X is NaN, infinite, or nonzero
and finite. The problematic cases are when X is zero, and its mode
has signed zeros. In the case of rounding towards -infinity,
X - 0 is not the same as X because 0 - 0 is -0. In other rounding
if (!real_zerop (addend))
return false;
+ /* Don't allow the fold with -fsignaling-nans. */
+ if (HONOR_SNANS (TYPE_MODE (type)))
+ return false;
+
/* Allow the fold if zeros aren't signed, or their sign isn't important. */
if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
return true;
return negate && !HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type));
}
+/* Subroutine of fold() that checks comparisons of built-in math
+ functions against real constants.
+
+ FCODE is the DECL_FUNCTION_CODE of the built-in, CODE is the comparison
+ operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR, GE_EXPR or LE_EXPR. TYPE
+ is the type of the result and ARG0 and ARG1 are the operands of the
+ comparison. ARG1 must be a TREE_REAL_CST.
+
+ The function returns the constant folded tree if a simplification
+ can be made, and NULL_TREE otherwise. */
+
+static tree
+fold_mathfn_compare (fcode, code, type, arg0, arg1)
+ enum built_in_function fcode;
+ enum tree_code code;
+ tree type, arg0, arg1;
+{
+ REAL_VALUE_TYPE c;
+
+ if (fcode == BUILT_IN_SQRT
+ || fcode == BUILT_IN_SQRTF
+ || fcode == BUILT_IN_SQRTL)
+ {
+ tree arg = TREE_VALUE (TREE_OPERAND (arg0, 1));
+ enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg0));
+
+ c = TREE_REAL_CST (arg1);
+ if (REAL_VALUE_NEGATIVE (c))
+ {
+ /* sqrt(x) < y is always false, if y is negative. */
+ if (code == EQ_EXPR || code == LT_EXPR || code == LE_EXPR)
+ return omit_one_operand (type,
+ convert (type, integer_zero_node),
+ arg);
+
+ /* sqrt(x) > y is always true, if y is negative and we
+ don't care about NaNs, i.e. negative values of x. */
+ if (code == NE_EXPR || !HONOR_NANS (mode))
+ return omit_one_operand (type,
+ convert (type, integer_one_node),
+ arg);
+
+ /* sqrt(x) > y is the same as x >= 0, if y is negative. */
+ return fold (build (GE_EXPR, type, arg,
+ build_real (TREE_TYPE (arg), dconst0)));
+ }
+ else if (code == GT_EXPR || code == GE_EXPR)
+ {
+ REAL_VALUE_TYPE c2;
+
+ REAL_ARITHMETIC (c2, MULT_EXPR, c, c);
+ real_convert (&c2, mode, &c2);
+
+ if (REAL_VALUE_ISINF (c2))
+ {
+ /* sqrt(x) > y is x == +Inf, when y is very large. */
+ if (HONOR_INFINITIES (mode))
+ return fold (build (EQ_EXPR, type, arg,
+ build_real (TREE_TYPE (arg), c2)));
+
+ /* sqrt(x) > y is always false, when y is very large
+ and we don't care about infinities. */
+ return omit_one_operand (type,
+ convert (type, integer_zero_node),
+ arg);
+ }
+
+ /* sqrt(x) > c is the same as x > c*c. */
+ return fold (build (code, type, arg,
+ build_real (TREE_TYPE (arg), c2)));
+ }
+ else if (code == LT_EXPR || code == LE_EXPR)
+ {
+ REAL_VALUE_TYPE c2;
+
+ REAL_ARITHMETIC (c2, MULT_EXPR, c, c);
+ real_convert (&c2, mode, &c2);
+
+ if (REAL_VALUE_ISINF (c2))
+ {
+ /* sqrt(x) < y is always true, when y is a very large
+ value and we don't care about NaNs or Infinities. */
+ if (! HONOR_NANS (mode) && ! HONOR_INFINITIES (mode))
+ return omit_one_operand (type,
+ convert (type, integer_one_node),
+ arg);
+
+ /* sqrt(x) < y is x != +Inf when y is very large and we
+ don't care about NaNs. */
+ if (! HONOR_NANS (mode))
+ return fold (build (NE_EXPR, type, arg,
+ build_real (TREE_TYPE (arg), c2)));
+
+ /* sqrt(x) < y is x >= 0 when y is very large and we
+ don't care about Infinities. */
+ if (! HONOR_INFINITIES (mode))
+ return fold (build (GE_EXPR, type, arg,
+ build_real (TREE_TYPE (arg), dconst0)));
+
+ /* sqrt(x) < y is x >= 0 && x != +Inf, when y is large. */
+ if ((*lang_hooks.decls.global_bindings_p) () != 0
+ || contains_placeholder_p (arg))
+ return NULL_TREE;
+
+ arg = save_expr (arg);
+ return fold (build (TRUTH_ANDIF_EXPR, type,
+ fold (build (GE_EXPR, type, arg,
+ build_real (TREE_TYPE (arg),
+ dconst0))),
+ fold (build (NE_EXPR, type, arg,
+ build_real (TREE_TYPE (arg),
+ c2)))));
+ }
+
+ /* sqrt(x) < c is the same as x < c*c, if we ignore NaNs. */
+ if (! HONOR_NANS (mode))
+ return fold (build (code, type, arg,
+ build_real (TREE_TYPE (arg), c2)));
+
+ /* sqrt(x) < c is the same as x >= 0 && x < c*c. */
+ if ((*lang_hooks.decls.global_bindings_p) () == 0
+ && ! contains_placeholder_p (arg))
+ {
+ arg = save_expr (arg);
+ return fold (build (TRUTH_ANDIF_EXPR, type,
+ fold (build (GE_EXPR, type, arg,
+ build_real (TREE_TYPE (arg),
+ dconst0))),
+ fold (build (code, type, arg,
+ build_real (TREE_TYPE (arg),
+ c2)))));
+ }
+ }
+ }
+
+ return NULL_TREE;
+}
+
+/* Subroutine of fold() that optimizes comparisons against Infinities,
+ either +Inf or -Inf.
+
+ CODE is the comparison operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR,
+ GE_EXPR or LE_EXPR. TYPE is the type of the result and ARG0 and ARG1
+ are the operands of the comparison. ARG1 must be a TREE_REAL_CST.
+
+ The function returns the constant folded tree if a simplification
+ can be made, and NULL_TREE otherwise. */
+
+static tree
+fold_inf_compare (code, type, arg0, arg1)
+ enum tree_code code;
+ tree type, arg0, arg1;
+{
+ /* For negative infinity swap the sense of the comparison. */
+ if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1)))
+ code = swap_tree_comparison (code);
+
+ switch (code)
+ {
+ case GT_EXPR:
+ /* x > +Inf is always false, if with ignore sNANs. */
+ if (HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0))))
+ return NULL_TREE;
+ return omit_one_operand (type,
+ convert (type, integer_zero_node),
+ arg0);
+
+ case LE_EXPR:
+ /* x <= +Inf is always true, if we don't case about NaNs. */
+ if (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
+ return omit_one_operand (type,
+ convert (type, integer_one_node),
+ arg0);
+
+ /* x <= +Inf is the same as x == x, i.e. isfinite(x). */
+ if ((*lang_hooks.decls.global_bindings_p) () == 0
+ && ! contains_placeholder_p (arg0))
+ {
+ arg0 = save_expr (arg0);
+ return fold (build (EQ_EXPR, type, arg0, arg0));
+ }
+ break;
+
+ case EQ_EXPR: /* ??? x == +Inf is x > DBL_MAX */
+ case GE_EXPR: /* ??? x >= +Inf is x > DBL_MAX */
+ case LT_EXPR: /* ??? x < +Inf is x <= DBL_MAX */
+ case NE_EXPR: /* ??? x != +Inf is !(x > DBL_MAX) */
+
+ default:
+ break;
+ }
+
+ return NULL_TREE;
+}
/* Perform constant folding and related simplification of EXPR.
The related simplifications include x*1 => x, x*0 => 0, etc.,
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));
t = fold (build (COND_EXPR, type, TREE_OPERAND (arg0, 0),
- fold (build1 (code, type, TREE_OPERAND (arg0, 1))),
- fold (build1 (code, type, TREE_OPERAND (arg0, 2)))));
+ 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
&& TREE_CODE (t) == COND_EXPR
&& TREE_CODE (TREE_OPERAND (t, 1)) == code
&& TREE_CODE (TREE_OPERAND (t, 2)) == code
+ && ! VOID_TYPE_P (TREE_OPERAND (t, 1))
+ && ! VOID_TYPE_P (TREE_OPERAND (t, 2))
&& (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 1), 0))
== TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 2), 0)))
&& ! (INTEGRAL_TYPE_P (TREE_TYPE (t))
else if (TREE_CODE_CLASS (code) == '2'
|| TREE_CODE_CLASS (code) == '<')
{
- if (TREE_CODE (arg1) == COMPOUND_EXPR)
+ if (TREE_CODE (arg1) == COMPOUND_EXPR
+ && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg1, 0))
+ && ! TREE_SIDE_EFFECTS (arg0))
return build (COMPOUND_EXPR, type, TREE_OPERAND (arg1, 0),
fold (build (code, type,
arg0, TREE_OPERAND (arg1, 1))));
&& (! TREE_SIDE_EFFECTS (arg0)
|| ((*lang_hooks.decls.global_bindings_p) () == 0
&& ! contains_placeholder_p (arg0))))
- return
+ return
fold_binary_op_with_conditional_arg (code, type, arg1, arg0,
/*cond_first_p=*/0);
else if (TREE_CODE (arg0) == COMPOUND_EXPR)
&& (! TREE_SIDE_EFFECTS (arg1)
|| ((*lang_hooks.decls.global_bindings_p) () == 0
&& ! contains_placeholder_p (arg1))))
- return
+ return
fold_binary_op_with_conditional_arg (code, type, arg0, arg1,
/*cond_first_p=*/1);
}
TREE_USED (t) = 1;
return t;
}
+
+ /* Convert (T)(x & c) into (T)x & (T)c, if c is an integer
+ constants (if x has signed type, the sign bit cannot be set
+ in c). This folds extension into the BIT_AND_EXPR. */
+ if (INTEGRAL_TYPE_P (TREE_TYPE (t))
+ && TREE_CODE (TREE_TYPE (t)) != BOOLEAN_TYPE
+ && TREE_CODE (TREE_OPERAND (t, 0)) == BIT_AND_EXPR
+ && TREE_CODE (TREE_OPERAND (TREE_OPERAND (t, 0), 1)) == INTEGER_CST)
+ {
+ tree and = TREE_OPERAND (t, 0);
+ tree and0 = TREE_OPERAND (and, 0), and1 = TREE_OPERAND (and, 1);
+ int change = 0;
+
+ if (TREE_UNSIGNED (TREE_TYPE (and))
+ || (TYPE_PRECISION (TREE_TYPE (t))
+ <= TYPE_PRECISION (TREE_TYPE (and))))
+ change = 1;
+ else if (TYPE_PRECISION (TREE_TYPE (and1))
+ <= HOST_BITS_PER_WIDE_INT
+ && host_integerp (and1, 1))
+ {
+ unsigned HOST_WIDE_INT cst;
+
+ cst = tree_low_cst (and1, 1);
+ cst &= (HOST_WIDE_INT) -1
+ << (TYPE_PRECISION (TREE_TYPE (and1)) - 1);
+ change = (cst == 0);
+#ifdef LOAD_EXTEND_OP
+ if (change
+ && (LOAD_EXTEND_OP (TYPE_MODE (TREE_TYPE (and0)))
+ == ZERO_EXTEND))
+ {
+ tree uns = (*lang_hooks.types.unsigned_type) (TREE_TYPE (and0));
+ and0 = convert (uns, and0);
+ and1 = convert (uns, and1);
+ }
+#endif
+ }
+ if (change)
+ return fold (build (BIT_AND_EXPR, TREE_TYPE (t),
+ convert (TREE_TYPE (t), and0),
+ convert (TREE_TYPE (t), and1)));
+ }
+
if (!wins)
{
TREE_CONSTANT (t) = TREE_CONSTANT (arg0);
}
else if (TREE_CODE (arg0) == NEGATE_EXPR)
return TREE_OPERAND (arg0, 0);
+ /* Convert -((double)float) into (double)(-float). */
+ else if (TREE_CODE (arg0) == NOP_EXPR
+ && TREE_CODE (type) == REAL_TYPE)
+ {
+ tree targ0 = strip_float_extensions (arg0);
+ if (targ0 != arg0)
+ return convert (type, build1 (NEGATE_EXPR, TREE_TYPE (targ0), targ0));
+
+ }
/* Convert - (a - b) to (b - a) for non-floating-point. */
else if (TREE_CODE (arg0) == MINUS_EXPR
}
else if (TREE_CODE (arg0) == ABS_EXPR || TREE_CODE (arg0) == NEGATE_EXPR)
return build1 (ABS_EXPR, type, TREE_OPERAND (arg0, 0));
+ /* Convert fabs((double)float) into (double)fabsf(float). */
+ else if (TREE_CODE (arg0) == NOP_EXPR
+ && TREE_CODE (type) == REAL_TYPE)
+ {
+ tree targ0 = strip_float_extensions (arg0);
+ if (targ0 != arg0)
+ return convert (type, build1 (ABS_EXPR, TREE_TYPE (targ0), targ0));
+
+ }
+ else
+ {
+ /* fabs(sqrt(x)) = sqrt(x) and fabs(exp(x)) = exp(x). */
+ enum built_in_function fcode = builtin_mathfn_code (arg0);
+ if (fcode == BUILT_IN_SQRT
+ || fcode == BUILT_IN_SQRTF
+ || fcode == BUILT_IN_SQRTL
+ || fcode == BUILT_IN_EXP
+ || fcode == BUILT_IN_EXPF
+ || fcode == BUILT_IN_EXPL)
+ t = arg0;
+ }
return t;
case CONJ_EXPR:
&& (! FLOAT_TYPE_P (type)
|| (flag_unsafe_math_optimizations && code == MULT_EXPR)))
{
- tree var0, con0, lit0, var1, con1, lit1;
+ tree var0, con0, lit0, minus_lit0;
+ tree var1, con1, lit1, minus_lit1;
/* Split both trees into variables, constants, and literals. Then
associate each group together, the constants with literals,
then the result with variables. This increases the chances of
literals being recombined later and of generating relocatable
expressions for the sum of a constant and literal. */
- var0 = split_tree (arg0, code, &con0, &lit0, 0);
- var1 = split_tree (arg1, code, &con1, &lit1, code == MINUS_EXPR);
+ var0 = split_tree (arg0, code, &con0, &lit0, &minus_lit0, 0);
+ var1 = split_tree (arg1, code, &con1, &lit1, &minus_lit1,
+ code == MINUS_EXPR);
/* Only do something if we found more than two objects. Otherwise,
nothing has changed and we risk infinite recursion. */
- if (2 < ((var0 != 0) + (var1 != 0) + (con0 != 0) + (con1 != 0)
- + (lit0 != 0) + (lit1 != 0)))
+ if (2 < ((var0 != 0) + (var1 != 0)
+ + (con0 != 0) + (con1 != 0)
+ + (lit0 != 0) + (lit1 != 0)
+ + (minus_lit0 != 0) + (minus_lit1 != 0)))
{
+ /* Recombine MINUS_EXPR operands by using PLUS_EXPR. */
+ if (code == MINUS_EXPR)
+ code = PLUS_EXPR;
+
var0 = associate_trees (var0, var1, code, type);
con0 = associate_trees (con0, con1, code, type);
lit0 = associate_trees (lit0, lit1, code, type);
- con0 = associate_trees (con0, lit0, code, type);
- return convert (type, associate_trees (var0, con0, code, type));
- }
+ minus_lit0 = associate_trees (minus_lit0, minus_lit1, code, type);
+
+ /* Preserve the MINUS_EXPR if the negative part of the literal is
+ greater than the positive part. Otherwise, the multiplicative
+ folding code (i.e extract_muldiv) may be fooled in case
+ unsigned constants are substracted, like in the following
+ example: ((X*2 + 4) - 8U)/2. */
+ if (minus_lit0 && lit0)
+ {
+ if (tree_int_cst_lt (lit0, minus_lit0))
+ {
+ minus_lit0 = associate_trees (minus_lit0, lit0,
+ MINUS_EXPR, type);
+ lit0 = 0;
+ }
+ else
+ {
+ lit0 = associate_trees (lit0, minus_lit0,
+ MINUS_EXPR, type);
+ minus_lit0 = 0;
+ }
+ }
+ if (minus_lit0)
+ {
+ if (con0 == 0)
+ return convert (type, associate_trees (var0, minus_lit0,
+ MINUS_EXPR, type));
+ else
+ {
+ con0 = associate_trees (con0, minus_lit0,
+ MINUS_EXPR, type);
+ return convert (type, associate_trees (var0, con0,
+ PLUS_EXPR, type));
+ }
+ }
+
+ con0 = associate_trees (con0, lit0, code, type);
+ return convert (type, associate_trees (var0, con0, code, type));
+ }
}
binary:
/* A - (-B) -> A + B */
if (TREE_CODE (arg1) == NEGATE_EXPR)
return fold (build (PLUS_EXPR, type, arg0, TREE_OPERAND (arg1, 0)));
- /* (-A) - CST -> (-CST) - A for floating point (what about ints ?) */
- if (TREE_CODE (arg0) == NEGATE_EXPR && TREE_CODE (arg1) == REAL_CST)
- return
- fold (build (MINUS_EXPR, type,
- build_real (TREE_TYPE (arg1),
- REAL_VALUE_NEGATE (TREE_REAL_CST (arg1))),
- TREE_OPERAND (arg0, 0)));
+ /* (-A) - B -> (-B) - A where B is easily negated and we can swap. */
+ if (TREE_CODE (arg0) == NEGATE_EXPR
+ && FLOAT_TYPE_P (type)
+ && negate_expr_p (arg1)
+ && (! TREE_SIDE_EFFECTS (arg0) || TREE_CONSTANT (arg1))
+ && (! TREE_SIDE_EFFECTS (arg1) || TREE_CONSTANT (arg0)))
+ return fold (build (MINUS_EXPR, type, negate_expr (arg1),
+ TREE_OPERAND (arg0, 0)));
if (! FLOAT_TYPE_P (type))
{
TREE_OPERAND (arg0, 0),
TREE_OPERAND (arg1, 0))),
TREE_OPERAND (arg0, 1)));
+
+ /* Fold A - (A & B) into ~B & A. */
+ if (!TREE_SIDE_EFFECTS (arg0)
+ && TREE_CODE (arg1) == BIT_AND_EXPR)
+ {
+ if (operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0))
+ return fold (build (BIT_AND_EXPR, type,
+ fold (build1 (BIT_NOT_EXPR, type,
+ TREE_OPERAND (arg1, 0))),
+ arg0));
+ if (operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
+ return fold (build (BIT_AND_EXPR, type,
+ fold (build1 (BIT_NOT_EXPR, type,
+ TREE_OPERAND (arg1, 1))),
+ arg0));
+ }
}
/* See if ARG1 is zero and X - ARG1 reduces to X. */
&& !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
&& real_zerop (arg1))
return omit_one_operand (type, arg1, arg0);
- /* In IEEE floating point, x*1 is not equivalent to x for snans.
- However, ANSI says we can drop signals,
- so we can do this anyway. */
- if (real_onep (arg1))
+ /* In IEEE floating point, x*1 is not equivalent to x for snans. */
+ if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
+ && real_onep (arg1))
return non_lvalue (convert (type, arg0));
+
+ /* Transform x * -1.0 into -x. */
+ if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
+ && real_minus_onep (arg1))
+ return fold (build1 (NEGATE_EXPR, type, arg0));
+
/* x*2 is x+x */
if (! wins && real_twop (arg1)
&& (*lang_hooks.decls.global_bindings_p) () == 0
tree arg = save_expr (arg0);
return build (PLUS_EXPR, type, arg, arg);
}
+
+ if (flag_unsafe_math_optimizations)
+ {
+ enum built_in_function fcode0 = builtin_mathfn_code (arg0);
+ enum built_in_function fcode1 = builtin_mathfn_code (arg1);
+
+ /* Optimize sqrt(x)*sqrt(y) as sqrt(x*y). */
+ if ((fcode0 == BUILT_IN_SQRT && fcode1 == BUILT_IN_SQRT)
+ || (fcode0 == BUILT_IN_SQRTF && fcode1 == BUILT_IN_SQRTF)
+ || (fcode0 == BUILT_IN_SQRTL && fcode1 == BUILT_IN_SQRTL))
+ {
+ tree sqrtfn = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0);
+ tree arg = build (MULT_EXPR, type,
+ TREE_VALUE (TREE_OPERAND (arg0, 1)),
+ TREE_VALUE (TREE_OPERAND (arg1, 1)));
+ tree arglist = build_tree_list (NULL_TREE, arg);
+ return fold (build_function_call_expr (sqrtfn, arglist));
+ }
+
+ /* Optimize exp(x)*exp(y) as exp(x+y). */
+ if ((fcode0 == BUILT_IN_EXP && fcode1 == BUILT_IN_EXP)
+ || (fcode0 == BUILT_IN_EXPF && fcode1 == BUILT_IN_EXPF)
+ || (fcode0 == BUILT_IN_EXPL && fcode1 == BUILT_IN_EXPL))
+ {
+ tree expfn = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0);
+ tree arg = build (PLUS_EXPR, type,
+ TREE_VALUE (TREE_OPERAND (arg0, 1)),
+ TREE_VALUE (TREE_OPERAND (arg1, 1)));
+ tree arglist = build_tree_list (NULL_TREE, arg);
+ return fold (build_function_call_expr (expfn, arglist));
+ }
+ }
}
goto associate;
if (t1 != NULL_TREE)
return t1;
/* Simplify ((int)c & 0x377) into (int)c, if c is unsigned char. */
- if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == NOP_EXPR
- && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg1, 0))))
- {
- unsigned int prec
- = TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg1, 0)));
-
- if (prec < BITS_PER_WORD && prec < HOST_BITS_PER_WIDE_INT
- && (~TREE_INT_CST_LOW (arg0)
- & (((HOST_WIDE_INT) 1 << prec) - 1)) == 0)
- return build1 (NOP_EXPR, type, TREE_OPERAND (arg1, 0));
- }
if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) == NOP_EXPR
&& TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0))))
{
return fold (build (RDIV_EXPR, type, TREE_OPERAND (arg0, 0),
TREE_OPERAND (arg1, 0)));
- /* In IEEE floating point, x/1 is not equivalent to x for snans.
- However, ANSI says we can drop signals, so we can do this anyway. */
- if (real_onep (arg1))
+ /* In IEEE floating point, x/1 is not equivalent to x for snans. */
+ if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
+ && real_onep (arg1))
return non_lvalue (convert (type, arg0));
/* If ARG1 is a constant, we can convert this to a multiply by the
TREE_OPERAND (arg1, 0)),
TREE_OPERAND (arg1, 1)));
}
+
+ /* Optimize x/exp(y) into x*exp(-y). */
+ if (flag_unsafe_math_optimizations)
+ {
+ enum built_in_function fcode = builtin_mathfn_code (arg1);
+ if (fcode == BUILT_IN_EXP
+ || fcode == BUILT_IN_EXPF
+ || fcode == BUILT_IN_EXPL)
+ {
+ tree expfn = TREE_OPERAND (TREE_OPERAND (arg1, 0), 0);
+ tree arg = build1 (NEGATE_EXPR, type,
+ TREE_VALUE (TREE_OPERAND (arg1, 1)));
+ tree arglist = build_tree_list (NULL_TREE, arg);
+ arg1 = build_function_call_expr (expfn, arglist);
+ return fold (build (MULT_EXPR, type, arg0, arg1));
+ }
+ }
goto binary;
case TRUNC_DIV_EXPR:
goto binary;
- case LSHIFT_EXPR:
- case RSHIFT_EXPR:
case LROTATE_EXPR:
case RROTATE_EXPR:
+ if (integer_all_onesp (arg0))
+ return omit_one_operand (type, arg0, arg1);
+ goto shift;
+
+ case RSHIFT_EXPR:
+ /* Optimize -1 >> x for arithmetic right shifts. */
+ if (integer_all_onesp (arg0) && ! TREE_UNSIGNED (type))
+ return omit_one_operand (type, arg0, arg1);
+ /* ... fall through ... */
+
+ case LSHIFT_EXPR:
+ shift:
if (integer_zerop (arg1))
return non_lvalue (convert (type, arg0));
+ if (integer_zerop (arg0))
+ return omit_one_operand (type, arg0, arg1);
+
/* Since negative shift count is not well-defined,
don't try to compute it in the compiler. */
if (TREE_CODE (arg1) == INTEGER_CST && tree_int_cst_sgn (arg1) < 0)
case GT_EXPR:
case LE_EXPR:
case GE_EXPR:
+ /* If one arg is a real or integer constant, put it last. */
+ if ((TREE_CODE (arg0) == INTEGER_CST
+ && TREE_CODE (arg1) != INTEGER_CST)
+ || (TREE_CODE (arg0) == REAL_CST
+ && TREE_CODE (arg0) != REAL_CST))
+ {
+ TREE_OPERAND (t, 0) = arg1;
+ TREE_OPERAND (t, 1) = arg0;
+ arg0 = TREE_OPERAND (t, 0);
+ arg1 = TREE_OPERAND (t, 1);
+ code = swap_tree_comparison (code);
+ TREE_SET_CODE (t, code);
+ }
+
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 (build (code, type, convert (newtype, targ0),
+ convert (newtype, targ1)));
+
/* (-a) CMP (-b) -> b CMP a */
if (TREE_CODE (arg0) == NEGATE_EXPR
&& TREE_CODE (arg1) == NEGATE_EXPR)
return fold (build (code, type, TREE_OPERAND (arg1, 0),
TREE_OPERAND (arg0, 0)));
- /* (-a) CMP CST -> a swap(CMP) (-CST) */
- if (TREE_CODE (arg0) == NEGATE_EXPR && TREE_CODE (arg1) == REAL_CST)
- return
- fold (build
- (swap_tree_comparison (code), type,
- TREE_OPERAND (arg0, 0),
- build_real (TREE_TYPE (arg1),
- REAL_VALUE_NEGATE (TREE_REAL_CST (arg1)))));
- /* IEEE doesn't distinguish +0 and -0 in comparisons. */
- /* a CMP (-0) -> a CMP 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 (build (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 (build (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))))
+ {
+ t = (code == NE_EXPR) ? integer_one_node : integer_zero_node;
+ return omit_one_operand (type, convert (type, t), 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 (build (code, type, TREE_OPERAND (arg0, 0), tem));
+
+ /* Fold comparisons against built-in math functions. */
if (TREE_CODE (arg1) == REAL_CST
- && REAL_VALUE_MINUS_ZERO (TREE_REAL_CST (arg1)))
- return fold (build (code, type, arg0,
- build_real (TREE_TYPE (arg1), dconst0)));
- }
+ && flag_unsafe_math_optimizations
+ && ! flag_errno_math)
+ {
+ enum built_in_function fcode = builtin_mathfn_code (arg0);
- /* If one arg is a constant integer, put it last. */
- if (TREE_CODE (arg0) == INTEGER_CST
- && TREE_CODE (arg1) != INTEGER_CST)
- {
- TREE_OPERAND (t, 0) = arg1;
- TREE_OPERAND (t, 1) = arg0;
- arg0 = TREE_OPERAND (t, 0);
- arg1 = TREE_OPERAND (t, 1);
- code = swap_tree_comparison (code);
- TREE_SET_CODE (t, code);
+ 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.
|| integer_onep (folded_compare))
return omit_one_operand (type, folded_compare, varop);
- unsigned_type = type_for_size (size, 1);
+ unsigned_type = (*lang_hooks.types.type_for_size)(size, 1);
precision = TYPE_PRECISION (unsigned_type);
mask = build_int_2 (~0, ~0);
TREE_TYPE (mask) = unsigned_type;
|| integer_onep (folded_compare))
return omit_one_operand (type, folded_compare, varop);
- unsigned_type = type_for_size (size, 1);
+ unsigned_type = (*lang_hooks.types.type_for_size)(size, 1);
precision = TYPE_PRECISION (unsigned_type);
mask = build_int_2 (~0, ~0);
TREE_TYPE (mask) = TREE_TYPE (varop);
}
}
- /* Change X >= CST to X > (CST - 1) if CST is positive. */
+ /* 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. */
if (TREE_CODE (arg1) == INTEGER_CST
&& TREE_CODE (arg0) != INTEGER_CST
&& tree_int_cst_sgn (arg1) > 0)
{
- switch (TREE_CODE (t))
+ switch (code)
{
case GE_EXPR:
code = GT_EXPR;
}
}
+ /* Comparisons with the highest or lowest possible integer of
+ the specified size will have known values. */
+ {
+ int width = GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg1)));
+
+ if (TREE_CODE (arg1) == INTEGER_CST
+ && ! TREE_CONSTANT_OVERFLOW (arg1)
+ && width <= HOST_BITS_PER_WIDE_INT
+ && (INTEGRAL_TYPE_P (TREE_TYPE (arg1))
+ || POINTER_TYPE_P (TREE_TYPE (arg1))))
+ {
+ unsigned HOST_WIDE_INT signed_max;
+ unsigned HOST_WIDE_INT max, min;
+
+ signed_max = ((unsigned HOST_WIDE_INT) 1 << (width - 1)) - 1;
+
+ if (TREE_UNSIGNED (TREE_TYPE (arg1)))
+ {
+ max = ((unsigned HOST_WIDE_INT) 2 << (width - 1)) - 1;
+ min = 0;
+ }
+ else
+ {
+ max = signed_max;
+ min = ((unsigned HOST_WIDE_INT) -1 << (width - 1));
+ }
+
+ if (TREE_INT_CST_HIGH (arg1) == 0
+ && TREE_INT_CST_LOW (arg1) == max)
+ switch (code)
+ {
+ case GT_EXPR:
+ return omit_one_operand (type,
+ convert (type, integer_zero_node),
+ arg0);
+ case GE_EXPR:
+ code = EQ_EXPR;
+ TREE_SET_CODE (t, EQ_EXPR);
+ break;
+ case LE_EXPR:
+ return omit_one_operand (type,
+ convert (type, integer_one_node),
+ arg0);
+ case LT_EXPR:
+ code = NE_EXPR;
+ TREE_SET_CODE (t, NE_EXPR);
+ break;
+
+ /* The GE_EXPR and LT_EXPR cases above are not normally
+ reached because of previous transformations. */
+
+ default:
+ break;
+ }
+ else if (TREE_INT_CST_HIGH (arg1) == 0
+ && TREE_INT_CST_LOW (arg1) == max - 1)
+ switch (code)
+ {
+ case GT_EXPR:
+ code = EQ_EXPR;
+ arg1 = const_binop (PLUS_EXPR, arg1, integer_one_node, 0);
+ t = build (code, type, TREE_OPERAND (t, 0), arg1);
+ break;
+ case LE_EXPR:
+ code = NE_EXPR;
+ arg1 = const_binop (PLUS_EXPR, arg1, integer_one_node, 0);
+ t = build (code, type, TREE_OPERAND (t, 0), arg1);
+ break;
+ default:
+ break;
+ }
+ else if (TREE_INT_CST_HIGH (arg1) == (min ? -1 : 0)
+ && TREE_INT_CST_LOW (arg1) == min)
+ switch (code)
+ {
+ case LT_EXPR:
+ return omit_one_operand (type,
+ convert (type, integer_zero_node),
+ arg0);
+ case LE_EXPR:
+ code = EQ_EXPR;
+ TREE_SET_CODE (t, EQ_EXPR);
+ break;
+
+ case GE_EXPR:
+ return omit_one_operand (type,
+ convert (type, integer_one_node),
+ arg0);
+ case GT_EXPR:
+ code = NE_EXPR;
+ TREE_SET_CODE (t, NE_EXPR);
+ break;
+
+ default:
+ break;
+ }
+ else if (TREE_INT_CST_HIGH (arg1) == (min ? -1 : 0)
+ && TREE_INT_CST_LOW (arg1) == min + 1)
+ switch (code)
+ {
+ case GE_EXPR:
+ code = NE_EXPR;
+ arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0);
+ t = build (code, type, TREE_OPERAND (t, 0), arg1);
+ break;
+ case LT_EXPR:
+ code = EQ_EXPR;
+ arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0);
+ t = build (code, type, TREE_OPERAND (t, 0), arg1);
+ break;
+ default:
+ break;
+ }
+
+ else if (TREE_INT_CST_HIGH (arg1) == 0
+ && TREE_INT_CST_LOW (arg1) == signed_max
+ && TREE_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
+ (build (code == LE_EXPR ? GE_EXPR: LT_EXPR,
+ type, convert (st0, arg0),
+ convert (st1, integer_zero_node)));
+ }
+ }
+ }
+ }
+
/* 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. */
|| TREE_CODE (arg0) == ROUND_MOD_EXPR)
&& integer_pow2p (TREE_OPERAND (arg0, 1)))
{
- tree newtype = unsigned_type (TREE_TYPE (arg0));
+ tree newtype = (*lang_hooks.types.unsigned_type) (TREE_TYPE (arg0));
tree newmod = build (TREE_CODE (arg0), newtype,
convert (newtype, TREE_OPERAND (arg0, 0)),
convert (newtype, TREE_OPERAND (arg0, 1)));
&& TREE_CODE (arg0) == BIT_AND_EXPR
&& integer_pow2p (TREE_OPERAND (arg0, 1))
&& operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
- return build (code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
- arg0, integer_zero_node);
+ return fold (build (code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
+ arg0, integer_zero_node));
+
+ /* If we have (A & C) != 0 where C is the sign bit of A, convert
+ this into A < 0. Similarly for (A & C) == 0 into A >= 0. */
+ if ((code == EQ_EXPR || code == NE_EXPR)
+ && TREE_CODE (arg0) == BIT_AND_EXPR
+ && integer_zerop (arg1))
+ {
+ tree arg00 = sign_bit_p (TREE_OPERAND (arg0, 0),
+ TREE_OPERAND (arg0, 1));
+ if (arg00 != NULL_TREE)
+ {
+ tree stype = (*lang_hooks.types.signed_type) (TREE_TYPE (arg00));
+ return fold (build (code == EQ_EXPR ? GE_EXPR : LT_EXPR, type,
+ convert (stype, arg00),
+ convert (stype, integer_zero_node)));
+ }
+ }
/* If X is unsigned, convert X < (1 << Y) into X >> Y == 0
and similarly for >= into !=. */
}
}
- /* An unsigned comparison against 0 can be simplified. */
- if (integer_zerop (arg1)
- && (INTEGRAL_TYPE_P (TREE_TYPE (arg1))
- || POINTER_TYPE_P (TREE_TYPE (arg1)))
- && TREE_UNSIGNED (TREE_TYPE (arg1)))
- {
- switch (TREE_CODE (t))
- {
- case GT_EXPR:
- code = NE_EXPR;
- TREE_SET_CODE (t, NE_EXPR);
- break;
- case LE_EXPR:
- code = EQ_EXPR;
- TREE_SET_CODE (t, EQ_EXPR);
- break;
- case GE_EXPR:
- return omit_one_operand (type,
- convert (type, integer_one_node),
- arg0);
- case LT_EXPR:
- return omit_one_operand (type,
- convert (type, integer_zero_node),
- arg0);
- default:
- break;
- }
- }
-
- /* Comparisons with the highest or lowest possible integer of
- the specified size will have known values and an unsigned
- <= 0x7fffffff can be simplified. */
- {
- int width = GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg1)));
-
- if (TREE_CODE (arg1) == INTEGER_CST
- && ! TREE_CONSTANT_OVERFLOW (arg1)
- && width <= HOST_BITS_PER_WIDE_INT
- && (INTEGRAL_TYPE_P (TREE_TYPE (arg1))
- || POINTER_TYPE_P (TREE_TYPE (arg1))))
- {
- if (TREE_INT_CST_HIGH (arg1) == 0
- && (TREE_INT_CST_LOW (arg1)
- == ((unsigned HOST_WIDE_INT) 1 << (width - 1)) - 1)
- && ! TREE_UNSIGNED (TREE_TYPE (arg1)))
- switch (TREE_CODE (t))
- {
- case GT_EXPR:
- return omit_one_operand (type,
- convert (type, integer_zero_node),
- arg0);
- case GE_EXPR:
- TREE_SET_CODE (t, EQ_EXPR);
- break;
-
- case LE_EXPR:
- return omit_one_operand (type,
- convert (type, integer_one_node),
- arg0);
- case LT_EXPR:
- TREE_SET_CODE (t, NE_EXPR);
- break;
-
- default:
- break;
- }
-
- else if (TREE_INT_CST_HIGH (arg1) == -1
- && (TREE_INT_CST_LOW (arg1)
- == ((unsigned HOST_WIDE_INT) 1 << (width - 1)))
- && ! TREE_UNSIGNED (TREE_TYPE (arg1)))
- switch (TREE_CODE (t))
- {
- case LT_EXPR:
- return omit_one_operand (type,
- convert (type, integer_zero_node),
- arg0);
- case LE_EXPR:
- TREE_SET_CODE (t, EQ_EXPR);
- break;
-
- case GE_EXPR:
- return omit_one_operand (type,
- convert (type, integer_one_node),
- arg0);
- case GT_EXPR:
- TREE_SET_CODE (t, NE_EXPR);
- break;
-
- default:
- break;
- }
-
- else if (TREE_INT_CST_HIGH (arg1) == 0
- && (TREE_INT_CST_LOW (arg1)
- == ((unsigned HOST_WIDE_INT) 1 << (width - 1)) - 1)
- && TREE_UNSIGNED (TREE_TYPE (arg1))
- /* signed_type does not work on pointer types. */
- && INTEGRAL_TYPE_P (TREE_TYPE (arg1)))
- switch (TREE_CODE (t))
- {
- case LE_EXPR:
- return fold (build (GE_EXPR, type,
- convert (signed_type (TREE_TYPE (arg0)),
- arg0),
- convert (signed_type (TREE_TYPE (arg1)),
- integer_zero_node)));
- case GT_EXPR:
- return fold (build (LT_EXPR, type,
- convert (signed_type (TREE_TYPE (arg0)),
- arg0),
- convert (signed_type (TREE_TYPE (arg1)),
- integer_zero_node)));
-
- default:
- break;
- }
-
- else if (TREE_INT_CST_HIGH (arg1) == 0
- && (TREE_INT_CST_LOW (arg1)
- == ((unsigned HOST_WIDE_INT) 2 << (width - 1)) - 1)
- && TREE_UNSIGNED (TREE_TYPE (arg1)))
- switch (TREE_CODE (t))
- {
- case GT_EXPR:
- return omit_one_operand (type,
- convert (type, integer_zero_node),
- arg0);
- case GE_EXPR:
- TREE_SET_CODE (t, EQ_EXPR);
- break;
-
- case LE_EXPR:
- return omit_one_operand (type,
- convert (type, integer_one_node),
- arg0);
- case LT_EXPR:
- TREE_SET_CODE (t, NE_EXPR);
- break;
-
- default:
- break;
- }
- }
- }
-
/* 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
}
/* If this is a comparison of a field, we may be able to simplify it. */
- if ((TREE_CODE (arg0) == COMPONENT_REF
+ 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
}
/* Optimize comparisons of strlen vs zero to a compare of the
- first character of the string vs zero. To wit,
+ 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)
TREE_TYPE (t1) = type;
if (TREE_CODE (type) == BOOLEAN_TYPE)
- return truthvalue_conversion (t1);
+ return (*lang_hooks.truthvalue_conversion) (t1);
return t1;
case COND_EXPR:
case GE_EXPR:
case GT_EXPR:
if (TREE_UNSIGNED (TREE_TYPE (arg1)))
- arg1 = convert (signed_type (TREE_TYPE (arg1)), arg1);
+ arg1 = convert ((*lang_hooks.types.signed_type)
+ (TREE_TYPE (arg1)), arg1);
return pedantic_non_lvalue
(convert (type, fold (build1 (ABS_EXPR,
TREE_TYPE (arg1), arg1))));
case LE_EXPR:
case LT_EXPR:
if (TREE_UNSIGNED (TREE_TYPE (arg1)))
- arg1 = convert (signed_type (TREE_TYPE (arg1)), arg1);
+ arg1 = convert ((lang_hooks.types.signed_type)
+ (TREE_TYPE (arg1)), arg1);
return pedantic_non_lvalue
(negate_expr (convert (type,
fold (build1 (ABS_EXPR,
/* Avoid adding NOP_EXPRs in case this is an lvalue. */
if (TYPE_MAIN_VARIANT (comp_type) == TYPE_MAIN_VARIANT (type))
- comp_type = type;
+ {
+ comp_type = type;
+ comp_op0 = arg1;
+ comp_op1 = arg2;
+ }
switch (comp_code)
{
&& type == TREE_TYPE (arg0))
return pedantic_non_lvalue (arg0);
+ /* Convert A ? 0 : 1 to !A. This prefers the use of NOT_EXPR
+ over COND_EXPR in cases such as floating point comparisons. */
+ if (integer_zerop (TREE_OPERAND (t, 1))
+ && integer_onep (TREE_OPERAND (t, 2))
+ && truth_value_p (TREE_CODE (arg0)))
+ return pedantic_non_lvalue (convert (type,
+ invert_truthvalue (arg0)));
+
/* Look for expressions of the form A & 2 ? 2 : 0. The result of this
operation is simply A & 2. */
arg1, 1))
return pedantic_non_lvalue (convert (type, TREE_OPERAND (arg0, 0)));
+ /* Convert A ? B : 0 into A && B if A and B are truth values. */
+ if (integer_zerop (TREE_OPERAND (t, 2))
+ && truth_value_p (TREE_CODE (arg0))
+ && truth_value_p (TREE_CODE (arg1)))
+ return pedantic_non_lvalue (fold (build (TRUTH_ANDIF_EXPR, type,
+ arg0, arg1)));
+
+ /* Convert A ? B : 1 into !A || B if A and B are truth values. */
+ if (integer_onep (TREE_OPERAND (t, 2))
+ && truth_value_p (TREE_CODE (arg0))
+ && 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 pedantic_non_lvalue (fold (build (TRUTH_ORIF_EXPR, type,
+ tem, arg1)));
+ }
+
return t;
case COMPOUND_EXPR:
{
case ABS_EXPR:
case FFS_EXPR:
+ case POPCOUNT_EXPR:
+ case PARITY_EXPR:
return 1;
+
+ case CLZ_EXPR:
+ case CTZ_EXPR:
+ /* These are undefined at zero. This is true even if
+ C[LT]Z_DEFINED_VALUE_AT_ZERO is set, since what we're
+ computing here is a user-visible property. */
+ return 0;
+
case INTEGER_CST:
return tree_int_cst_sgn (t) >= 0;
case TRUNC_DIV_EXPR:
case FLOOR_DIV_EXPR:
case ROUND_DIV_EXPR:
return tree_expr_nonnegative_p (TREE_OPERAND (t, 0))
- && tree_expr_nonnegative_p (TREE_OPERAND (t, 1));
+ && tree_expr_nonnegative_p (TREE_OPERAND (t, 1));
case TRUNC_MOD_EXPR:
case CEIL_MOD_EXPR:
case FLOOR_MOD_EXPR:
return tree_expr_nonnegative_p (TREE_OPERAND (t, 1));
case MIN_EXPR:
return tree_expr_nonnegative_p (TREE_OPERAND (t, 0))
- && tree_expr_nonnegative_p (TREE_OPERAND (t, 1));
+ && tree_expr_nonnegative_p (TREE_OPERAND (t, 1));
case MAX_EXPR:
return tree_expr_nonnegative_p (TREE_OPERAND (t, 0))
- || tree_expr_nonnegative_p (TREE_OPERAND (t, 1));
+ || tree_expr_nonnegative_p (TREE_OPERAND (t, 1));
case MODIFY_EXPR:
return tree_expr_nonnegative_p (TREE_OPERAND (t, 1));
case BIND_EXPR:
return tree_expr_nonnegative_p (TREE_OPERAND (t, 0));
case RTL_EXPR:
return rtl_expr_nonnegative_p (RTL_EXPR_RTL (t));
-
+
default:
if (truth_value_p (TREE_CODE (t)))
/* Truth values evaluate to 0 or 1, which is nonnegative. */
return 0;
}
}
+
+#include "gt-fold-const.h"
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