fold-const.c (fold_relational_hi_lo): Delete function and prototype.

* fold-const.c (fold_relational_hi_lo): Delete function and prototype.
	(fold_binary): Update comment mentioning fold_relational_hi_lo.
	(fold_binary_to_constant): Simplify using fold_binary.
	(fold_unary_to_constant): Likewise, simplify using fold_unary.

From-SVN: r98220
This commit is contained in:
Roger Sayle 2005-04-16 01:59:11 +00:00 committed by Roger Sayle
parent 3c60ae5ab5
commit 054632e8ab
2 changed files with 12 additions and 496 deletions

View File

@ -1,3 +1,10 @@
2005-04-15 Roger Sayle <roger@eyesopen.com>
* fold-const.c (fold_relational_hi_lo): Delete function and prototype.
(fold_binary): Update comment mentioning fold_relational_hi_lo.
(fold_binary_to_constant): Simplify using fold_binary.
(fold_unary_to_constant): Likewise, simplify using fold_unary.
2005-04-15 Rainer Orth <ro@TechFak.Uni-Bielefeld.DE>
* gthr-posix.c (pthread_cancel): Define.

View File

@ -133,8 +133,6 @@ static bool reorder_operands_p (tree, 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 tree fold_relational_hi_lo (enum tree_code *, const tree,
tree *, tree *);
static bool tree_expr_nonzero_p (tree);
/* We know that A1 + B1 = SUM1, using 2's complement arithmetic and ignoring
@ -9033,10 +9031,7 @@ fold_binary (enum tree_code code, tree type, tree op0, tree op1)
}
/* Comparisons with the highest or lowest possible integer of
the specified size will have known values.
This is quite similar to fold_relational_hi_lo, however,
attempts to share the code have been nothing but trouble. */
the specified size will have known values. */
{
int width = GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg1)));
@ -10793,155 +10788,6 @@ tree_expr_nonzero_p (tree t)
return false;
}
/* See if we are applying CODE, a relational to the highest or lowest
possible integer of TYPE. If so, then the result is a compile
time constant. */
static tree
fold_relational_hi_lo (enum tree_code *code_p, const tree type, tree *op0_p,
tree *op1_p)
{
tree op0 = *op0_p;
tree op1 = *op1_p;
enum tree_code code = *code_p;
int width = GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (op1)));
if (TREE_CODE (op1) == INTEGER_CST
&& ! TREE_CONSTANT_OVERFLOW (op1)
&& width <= HOST_BITS_PER_WIDE_INT
&& (INTEGRAL_TYPE_P (TREE_TYPE (op1))
|| POINTER_TYPE_P (TREE_TYPE (op1))))
{
unsigned HOST_WIDE_INT signed_max;
unsigned HOST_WIDE_INT max, min;
signed_max = ((unsigned HOST_WIDE_INT) 1 << (width - 1)) - 1;
if (TYPE_UNSIGNED (TREE_TYPE (op1)))
{
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 (op1) == 0
&& TREE_INT_CST_LOW (op1) == max)
switch (code)
{
case GT_EXPR:
return omit_one_operand (type, integer_zero_node, op0);
case GE_EXPR:
*code_p = EQ_EXPR;
break;
case LE_EXPR:
return omit_one_operand (type, integer_one_node, op0);
case LT_EXPR:
*code_p = 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 (op1) == 0
&& TREE_INT_CST_LOW (op1) == max - 1)
switch (code)
{
case GT_EXPR:
*code_p = EQ_EXPR;
*op1_p = const_binop (PLUS_EXPR, op1, integer_one_node, 0);
break;
case LE_EXPR:
*code_p = NE_EXPR;
*op1_p = const_binop (PLUS_EXPR, op1, integer_one_node, 0);
break;
default:
break;
}
else if (TREE_INT_CST_HIGH (op1) == (min ? -1 : 0)
&& TREE_INT_CST_LOW (op1) == min)
switch (code)
{
case LT_EXPR:
return omit_one_operand (type, integer_zero_node, op0);
case LE_EXPR:
*code_p = EQ_EXPR;
break;
case GE_EXPR:
return omit_one_operand (type, integer_one_node, op0);
case GT_EXPR:
*code_p = NE_EXPR;
break;
default:
break;
}
else if (TREE_INT_CST_HIGH (op1) == (min ? -1 : 0)
&& TREE_INT_CST_LOW (op1) == min + 1)
switch (code)
{
case GE_EXPR:
*code_p = NE_EXPR;
*op1_p = const_binop (MINUS_EXPR, op1, integer_one_node, 0);
break;
case LT_EXPR:
*code_p = EQ_EXPR;
*op1_p = const_binop (MINUS_EXPR, op1, integer_one_node, 0);
break;
default:
break;
}
else if (TREE_INT_CST_HIGH (op1) == 0
&& TREE_INT_CST_LOW (op1) == signed_max
&& TYPE_UNSIGNED (TREE_TYPE (op1))
/* signed_type does not work on pointer types. */
&& INTEGRAL_TYPE_P (TREE_TYPE (op1)))
{
/* 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, exp, retval;
st0 = lang_hooks.types.signed_type (TREE_TYPE (op0));
st1 = lang_hooks.types.signed_type (TREE_TYPE (op1));
exp = build2 (code == LE_EXPR ? GE_EXPR: LT_EXPR,
type,
fold_convert (st0, op0),
fold_convert (st1, integer_zero_node));
retval = fold_binary_to_constant (TREE_CODE (exp),
TREE_TYPE (exp),
TREE_OPERAND (exp, 0),
TREE_OPERAND (exp, 1));
/* If we are in gimple form, then returning EXP would create
non-gimple expressions. Clearing it is safe and insures
we do not allow a non-gimple expression to escape. */
if (in_gimple_form)
exp = NULL;
return (retval ? retval : exp);
}
}
}
return NULL_TREE;
}
/* Given the components of a binary expression CODE, TYPE, OP0 and OP1,
attempt to fold the expression to a constant without modifying TYPE,
OP0 or OP1.
@ -10958,282 +10804,8 @@ fold_relational_hi_lo (enum tree_code *code_p, const tree type, tree *op0_p,
tree
fold_binary_to_constant (enum tree_code code, tree type, tree op0, tree op1)
{
int wins = 1;
tree subop0;
tree subop1;
tree tem;
/* If this is a commutative operation, and ARG0 is a constant, move it
to ARG1 to reduce the number of tests below. */
if (commutative_tree_code (code)
&& (TREE_CODE (op0) == INTEGER_CST || TREE_CODE (op0) == REAL_CST))
{
tem = op0;
op0 = op1;
op1 = tem;
}
/* If either operand is a complex type, extract its real component. */
if (TREE_CODE (op0) == COMPLEX_CST)
subop0 = TREE_REALPART (op0);
else
subop0 = op0;
if (TREE_CODE (op1) == COMPLEX_CST)
subop1 = TREE_REALPART (op1);
else
subop1 = op1;
/* Note if either argument is not a real or integer constant.
With a few exceptions, simplification is limited to cases
where both arguments are constants. */
if ((TREE_CODE (subop0) != INTEGER_CST
&& TREE_CODE (subop0) != REAL_CST)
|| (TREE_CODE (subop1) != INTEGER_CST
&& TREE_CODE (subop1) != REAL_CST))
wins = 0;
switch (code)
{
case PLUS_EXPR:
/* (plus (address) (const_int)) is a constant. */
if (TREE_CODE (op0) == PLUS_EXPR
&& TREE_CODE (op1) == INTEGER_CST
&& (TREE_CODE (TREE_OPERAND (op0, 0)) == ADDR_EXPR
|| (TREE_CODE (TREE_OPERAND (op0, 0)) == NOP_EXPR
&& (TREE_CODE (TREE_OPERAND (TREE_OPERAND (op0, 0), 0))
== ADDR_EXPR)))
&& TREE_CODE (TREE_OPERAND (op0, 1)) == INTEGER_CST)
{
return build2 (PLUS_EXPR, type, TREE_OPERAND (op0, 0),
const_binop (PLUS_EXPR, op1,
TREE_OPERAND (op0, 1), 0));
}
case BIT_XOR_EXPR:
binary:
if (!wins)
return NULL_TREE;
/* Both arguments are constants. Simplify. */
tem = const_binop (code, op0, op1, 0);
if (tem != NULL_TREE)
{
/* The return value should always have the same type as
the original expression. */
if (TREE_TYPE (tem) != type)
tem = fold_convert (type, tem);
return tem;
}
return NULL_TREE;
case MINUS_EXPR:
/* Fold &x - &x. This can happen from &x.foo - &x.
This is unsafe for certain floats even in non-IEEE formats.
In IEEE, it is unsafe because it does wrong for NaNs.
Also note that operand_equal_p is always false if an
operand is volatile. */
if (! FLOAT_TYPE_P (type) && operand_equal_p (op0, op1, 0))
return fold_convert (type, integer_zero_node);
goto binary;
case MULT_EXPR:
case BIT_AND_EXPR:
/* Special case multiplication or bitwise AND where one argument
is zero. */
if (! FLOAT_TYPE_P (type) && integer_zerop (op1))
return omit_one_operand (type, op1, op0);
else
if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (op0)))
&& !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (op0)))
&& real_zerop (op1))
return omit_one_operand (type, op1, op0);
goto binary;
case BIT_IOR_EXPR:
/* Special case when we know the result will be all ones. */
if (integer_all_onesp (op1))
return omit_one_operand (type, op1, op0);
goto binary;
case TRUNC_DIV_EXPR:
case ROUND_DIV_EXPR:
case FLOOR_DIV_EXPR:
case CEIL_DIV_EXPR:
case EXACT_DIV_EXPR:
case TRUNC_MOD_EXPR:
case ROUND_MOD_EXPR:
case FLOOR_MOD_EXPR:
case CEIL_MOD_EXPR:
case RDIV_EXPR:
/* Division by zero is undefined. */
if (integer_zerop (op1))
return NULL_TREE;
if (TREE_CODE (op1) == REAL_CST
&& !MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (op1)))
&& real_zerop (op1))
return NULL_TREE;
goto binary;
case MIN_EXPR:
if (INTEGRAL_TYPE_P (type)
&& operand_equal_p (op1, TYPE_MIN_VALUE (type), OEP_ONLY_CONST))
return omit_one_operand (type, op1, op0);
goto binary;
case MAX_EXPR:
if (INTEGRAL_TYPE_P (type)
&& TYPE_MAX_VALUE (type)
&& operand_equal_p (op1, TYPE_MAX_VALUE (type), OEP_ONLY_CONST))
return omit_one_operand (type, op1, op0);
goto binary;
case RSHIFT_EXPR:
/* Optimize -1 >> x for arithmetic right shifts. */
if (integer_all_onesp (op0) && ! TYPE_UNSIGNED (type))
return omit_one_operand (type, op0, op1);
/* ... fall through ... */
case LSHIFT_EXPR:
if (integer_zerop (op0))
return omit_one_operand (type, op0, op1);
/* Since negative shift count is not well-defined, don't
try to compute it in the compiler. */
if (TREE_CODE (op1) == INTEGER_CST && tree_int_cst_sgn (op1) < 0)
return NULL_TREE;
goto binary;
case LROTATE_EXPR:
case RROTATE_EXPR:
/* -1 rotated either direction by any amount is still -1. */
if (integer_all_onesp (op0))
return omit_one_operand (type, op0, op1);
/* 0 rotated either direction by any amount is still zero. */
if (integer_zerop (op0))
return omit_one_operand (type, op0, op1);
goto binary;
case COMPLEX_EXPR:
if (wins)
return build_complex (type, op0, op1);
return NULL_TREE;
case LT_EXPR:
case LE_EXPR:
case GT_EXPR:
case GE_EXPR:
case EQ_EXPR:
case NE_EXPR:
/* If one arg is a real or integer constant, put it last. */
if ((TREE_CODE (op0) == INTEGER_CST
&& TREE_CODE (op1) != INTEGER_CST)
|| (TREE_CODE (op0) == REAL_CST
&& TREE_CODE (op0) != REAL_CST))
{
tree temp;
temp = op0;
op0 = op1;
op1 = temp;
code = swap_tree_comparison (code);
}
/* 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 (op1) == INTEGER_CST
&& TREE_CODE (op0) != INTEGER_CST
&& tree_int_cst_sgn (op1) > 0)
{
switch (code)
{
case GE_EXPR:
code = GT_EXPR;
op1 = const_binop (MINUS_EXPR, op1, integer_one_node, 0);
break;
case LT_EXPR:
code = LE_EXPR;
op1 = const_binop (MINUS_EXPR, op1, integer_one_node, 0);
break;
default:
break;
}
}
tem = fold_relational_hi_lo (&code, type, &op0, &op1);
if (tem)
return tem;
/* Fall through. */
case ORDERED_EXPR:
case UNORDERED_EXPR:
case UNLT_EXPR:
case UNLE_EXPR:
case UNGT_EXPR:
case UNGE_EXPR:
case UNEQ_EXPR:
case LTGT_EXPR:
if (!wins)
return NULL_TREE;
return fold_relational_const (code, type, op0, op1);
case RANGE_EXPR:
/* This could probably be handled. */
return NULL_TREE;
case TRUTH_AND_EXPR:
/* If second arg is constant zero, result is zero, but first arg
must be evaluated. */
if (integer_zerop (op1))
return omit_one_operand (type, op1, op0);
/* Likewise for first arg, but note that only the TRUTH_AND_EXPR
case will be handled here. */
if (integer_zerop (op0))
return omit_one_operand (type, op0, op1);
if (TREE_CODE (op0) == INTEGER_CST && TREE_CODE (op1) == INTEGER_CST)
return constant_boolean_node (true, type);
return NULL_TREE;
case TRUTH_OR_EXPR:
/* If second arg is constant true, result is true, but we must
evaluate first arg. */
if (TREE_CODE (op1) == INTEGER_CST && ! integer_zerop (op1))
return omit_one_operand (type, op1, op0);
/* Likewise for first arg, but note this only occurs here for
TRUTH_OR_EXPR. */
if (TREE_CODE (op0) == INTEGER_CST && ! integer_zerop (op0))
return omit_one_operand (type, op0, op1);
if (TREE_CODE (op0) == INTEGER_CST && TREE_CODE (op1) == INTEGER_CST)
return constant_boolean_node (false, type);
return NULL_TREE;
case TRUTH_XOR_EXPR:
if (TREE_CODE (op0) == INTEGER_CST && TREE_CODE (op1) == INTEGER_CST)
{
int x = ! integer_zerop (op0) ^ ! integer_zerop (op1);
return constant_boolean_node (x, type);
}
return NULL_TREE;
default:
return NULL_TREE;
}
tree tem = fold_binary (code, type, op0, op1);
return (tem && TREE_CONSTANT (tem)) ? tem : NULL_TREE;
}
/* Given the components of a unary expression CODE, TYPE and OP0,
@ -11252,71 +10824,8 @@ fold_binary_to_constant (enum tree_code code, tree type, tree op0, tree op1)
tree
fold_unary_to_constant (enum tree_code code, tree type, tree op0)
{
/* Make sure we have a suitable constant argument. */
if (code == NOP_EXPR || code == FLOAT_EXPR || code == CONVERT_EXPR)
{
tree subop;
if (TREE_CODE (op0) == COMPLEX_CST)
subop = TREE_REALPART (op0);
else
subop = op0;
if (TREE_CODE (subop) != INTEGER_CST && TREE_CODE (subop) != REAL_CST)
return NULL_TREE;
}
switch (code)
{
case NOP_EXPR:
case FLOAT_EXPR:
case CONVERT_EXPR:
case FIX_TRUNC_EXPR:
case FIX_FLOOR_EXPR:
case FIX_CEIL_EXPR:
case FIX_ROUND_EXPR:
return fold_convert_const (code, type, op0);
case NEGATE_EXPR:
if (TREE_CODE (op0) == INTEGER_CST || TREE_CODE (op0) == REAL_CST)
return fold_negate_const (op0, type);
else
return NULL_TREE;
case ABS_EXPR:
if (TREE_CODE (op0) == INTEGER_CST || TREE_CODE (op0) == REAL_CST)
return fold_abs_const (op0, type);
else
return NULL_TREE;
case BIT_NOT_EXPR:
if (TREE_CODE (op0) == INTEGER_CST)
return fold_not_const (op0, type);
else
return NULL_TREE;
case REALPART_EXPR:
if (TREE_CODE (op0) == COMPLEX_CST)
return TREE_REALPART (op0);
else
return NULL_TREE;
case IMAGPART_EXPR:
if (TREE_CODE (op0) == COMPLEX_CST)
return TREE_IMAGPART (op0);
else
return NULL_TREE;
case CONJ_EXPR:
if (TREE_CODE (op0) == COMPLEX_CST
&& TREE_CODE (TREE_TYPE (op0)) == COMPLEX_TYPE)
return build_complex (type, TREE_REALPART (op0),
negate_expr (TREE_IMAGPART (op0)));
return NULL_TREE;
default:
return NULL_TREE;
}
tree tem = fold_unary (code, type, op0);
return (tem && TREE_CONSTANT (tem)) ? tem : NULL_TREE;
}
/* If EXP represents referencing an element in a constant string