/* 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 Free Software Foundation, Inc.
+ 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
This file is part of GCC.
{
if (ISXDIGIT (c))
{
- k = c & CHARMASK;
- if (k >= 'a' && k <= 'f')
- k = k - 'a' + 10;
- else if (k >= 'A')
- k = k - 'A' + 10;
- else
- k = k - '0';
+ k = hex_value (c & CHARMASK);
if ((high & 0xf0000000) == 0)
{
break;
}
- return convert (type, build1 (NEGATE_EXPR, TREE_TYPE (t), t));
+ return convert (type, fold (build1 (NEGATE_EXPR, TREE_TYPE (t), t)));
}
\f
/* Split a tree IN into a constant, literal and variable parts that could be
{
tree arg1; /* Input: value to convert. */
tree type; /* Input: type to convert value to. */
- tree t; /* Ouput: result of conversion. */
+ tree t; /* Output: result of conversion. */
};
/* Function to convert floating-point constants, protected by floating
enum machine_mode lmode, rmode, nmode;
int lunsignedp, runsignedp;
int lvolatilep = 0, rvolatilep = 0;
- unsigned int alignment;
tree linner, rinner = NULL_TREE;
tree mask;
tree offset;
do anything if the inner expression is a PLACEHOLDER_EXPR since we
then will no longer be able to replace it. */
linner = get_inner_reference (lhs, &lbitsize, &lbitpos, &offset, &lmode,
- &lunsignedp, &lvolatilep, &alignment);
+ &lunsignedp, &lvolatilep);
if (linner == lhs || lbitsize == GET_MODE_BITSIZE (lmode) || lbitsize < 0
|| offset != 0 || TREE_CODE (linner) == PLACEHOLDER_EXPR)
return 0;
/* If this is not a constant, we can only do something if bit positions,
sizes, and signedness are the same. */
rinner = get_inner_reference (rhs, &rbitsize, &rbitpos, &offset, &rmode,
- &runsignedp, &rvolatilep, &alignment);
+ &runsignedp, &rvolatilep);
if (rinner == rhs || lbitpos != rbitpos || lbitsize != rbitsize
|| lunsignedp != runsignedp || offset != 0
convert (unsigned_type, rhs),
size_int (lbitsize), 0)))
{
- warning ("comparison is always %d due to width of bitfield",
+ warning ("comparison is always %d due to width of bit-field",
code == NE_EXPR);
return convert (compare_type,
(code == NE_EXPR
size_int (lbitsize - 1), 0);
if (! integer_zerop (tem) && ! integer_all_onesp (tem))
{
- warning ("comparison is always %d due to width of bitfield",
+ warning ("comparison is always %d due to width of bit-field",
code == NE_EXPR);
return convert (compare_type,
(code == NE_EXPR
tree mask, inner, offset;
tree unsigned_type;
unsigned int precision;
- unsigned int alignment;
/* All the optimizations using this function assume integer fields.
There are problems with FP fields since the type_for_size call
}
inner = get_inner_reference (exp, pbitsize, pbitpos, &offset, pmode,
- punsignedp, pvolatilep, &alignment);
+ punsignedp, pvolatilep);
if ((inner == exp && and_mask == 0)
|| *pbitsize < 0 || offset != 0
|| TREE_CODE (inner) == PLACEHOLDER_EXPR)
side of the expression to be executed if the condition is true
will be pointed to by TRUE_LHS. Similarly, the right-hand side
of the expression to be executed if the condition is true will be
- pointed to by TRUE_RHS. FALSE_LHS and FALSE_RHS are analagous --
+ pointed to by TRUE_RHS. FALSE_LHS and FALSE_RHS are analogous --
but apply to the expression to be executed if the conditional is
false. */
tree *true_lhs;
}
return fold_convert (t, arg0);
+ case VIEW_CONVERT_EXPR:
+ if (TREE_CODE (TREE_OPERAND (t, 0)) == VIEW_CONVERT_EXPR)
+ return build1 (VIEW_CONVERT_EXPR, type,
+ TREE_OPERAND (TREE_OPERAND (t, 0), 0));
+ return t;
+
#if 0 /* This loses on &"foo"[0]. */
case ARRAY_REF:
{
}
else if (TREE_INT_CST_HIGH (arg1) == -1
- && (- TREE_INT_CST_LOW (arg1)
+ && (TREE_INT_CST_LOW (arg1)
== ((unsigned HOST_WIDE_INT) 1 << (width - 1)))
&& ! TREE_UNSIGNED (TREE_TYPE (arg1)))
switch (TREE_CODE (t))
}
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)))
-
+ && (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:
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;
+ }
}
}
fold (build (code, type, imag0, imag1))));
}
+ /* 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_CODE (TREE_OPERAND (arg0, 0)) == ADDR_EXPR)
+ {
+ tree fndecl = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0);
+ tree arglist;
+
+ if (TREE_CODE (fndecl) == FUNCTION_DECL
+ && DECL_BUILT_IN (fndecl)
+ && DECL_BUILT_IN_CLASS (fndecl) != BUILT_IN_MD
+ && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_STRLEN
+ && (arglist = TREE_OPERAND (arg0, 1))
+ && TREE_CODE (TREE_TYPE (TREE_VALUE (arglist))) == POINTER_TYPE
+ && ! TREE_CHAIN (arglist))
+ return fold (build (code, type,
+ build1 (INDIRECT_REF, char_type_node,
+ TREE_VALUE(arglist)),
+ integer_zero_node));
+ }
+
/* From here on, the only cases we handle are when the result is
known to be a constant.
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