/* Utility routines for data type conversion for GNU C.
- Copyright (C) 1987, 1988, 1991, 1992 Free Software Foundation, Inc.
+ Copyright (C) 1987, 1988, 1991, 1992, 1993, 1994, 1995, 1997,
+ 1998 Free Software Foundation, Inc.
-This file is part of GNU C.
+This file is part of GCC.
-GNU CC is free software; you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 2, or (at your option)
-any later version.
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 2, or (at your option) any later
+version.
-GNU CC is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-GNU General Public License for more details.
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+for more details.
You should have received a copy of the GNU General Public License
-along with GNU CC; see the file COPYING. If not, write to
-the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
+along with GCC; see the file COPYING. If not, write to the Free
+Software Foundation, 59 Temple Place - Suite 330, Boston, MA
+02111-1307, USA. */
/* These routines are somewhat language-independent utility function
- intended to be called by the language-specific convert () functions. */
+ intended to be called by the language-specific convert () functions. */
#include "config.h"
+#include "system.h"
#include "tree.h"
#include "flags.h"
#include "convert.h"
+#include "toplev.h"
+#include "langhooks.h"
-/* Convert EXPR to some pointer type TYPE.
+/* Convert EXPR to some pointer or reference type TYPE.
- EXPR must be pointer, integer, enumeral, or literal zero;
- in other cases error is called. */
+ EXPR must be pointer, reference, integer, enumeral, or literal zero;
+ in other cases error is called. */
tree
convert_to_pointer (type, expr)
tree type, expr;
{
- register tree intype = TREE_TYPE (expr);
- register enum tree_code form = TREE_CODE (intype);
-
if (integer_zerop (expr))
{
- if (type == TREE_TYPE (null_pointer_node))
- return null_pointer_node;
expr = build_int_2 (0, 0);
TREE_TYPE (expr) = type;
return expr;
}
- if (form == POINTER_TYPE)
- return build1 (NOP_EXPR, type, expr);
-
-
- if (form == INTEGER_TYPE || form == ENUMERAL_TYPE)
+ switch (TREE_CODE (TREE_TYPE (expr)))
{
- if (type_precision (intype) == POINTER_SIZE)
+ case POINTER_TYPE:
+ case REFERENCE_TYPE:
+ return build1 (NOP_EXPR, type, expr);
+
+ case INTEGER_TYPE:
+ case ENUMERAL_TYPE:
+ case BOOLEAN_TYPE:
+ case CHAR_TYPE:
+ if (TYPE_PRECISION (TREE_TYPE (expr)) == POINTER_SIZE)
return build1 (CONVERT_EXPR, type, expr);
- expr = convert (type_for_size (POINTER_SIZE, 0), expr);
- /* Modes may be different but sizes should be the same. */
- if (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (expr)))
- != GET_MODE_SIZE (TYPE_MODE (type)))
- /* There is supposed to be some integral type
- that is the same width as a pointer. */
- abort ();
- return convert_to_pointer (type, expr);
- }
- error ("cannot convert to a pointer type");
+ return
+ convert_to_pointer (type,
+ convert ((*lang_hooks.types.type_for_size)
+ (POINTER_SIZE, 0), expr));
- return null_pointer_node;
+ default:
+ error ("cannot convert to a pointer type");
+ return convert_to_pointer (type, integer_zero_node);
+ }
}
/* Convert EXPR to some floating-point type TYPE.
EXPR must be float, integer, or enumeral;
- in other cases error is called. */
+ in other cases error is called. */
tree
convert_to_real (type, expr)
tree type, expr;
{
- register enum tree_code form = TREE_CODE (TREE_TYPE (expr));
-
- if (form == REAL_TYPE)
- return build1 (flag_float_store ? CONVERT_EXPR : NOP_EXPR,
- type, expr);
-
- if (form == INTEGER_TYPE || form == ENUMERAL_TYPE)
- return build1 (FLOAT_EXPR, type, expr);
-
- if (form == COMPLEX_TYPE)
- return convert (type, fold (build1 (REALPART_EXPR,
- TREE_TYPE (TREE_TYPE (expr)), expr)));
-
- if (form == POINTER_TYPE)
- error ("pointer value used where a floating point value was expected");
- else
- error ("aggregate value used where a float was expected");
-
- {
- register tree tem = make_node (REAL_CST);
- TREE_TYPE (tem) = type;
- TREE_REAL_CST (tem) = REAL_VALUE_ATOF ("0.0", TYPE_MODE (type));
- return tem;
- }
+ switch (TREE_CODE (TREE_TYPE (expr)))
+ {
+ case REAL_TYPE:
+ return build1 (flag_float_store ? CONVERT_EXPR : NOP_EXPR,
+ type, expr);
+
+ case INTEGER_TYPE:
+ case ENUMERAL_TYPE:
+ case BOOLEAN_TYPE:
+ case CHAR_TYPE:
+ return build1 (FLOAT_EXPR, type, expr);
+
+ case COMPLEX_TYPE:
+ return convert (type,
+ fold (build1 (REALPART_EXPR,
+ TREE_TYPE (TREE_TYPE (expr)), expr)));
+
+ case POINTER_TYPE:
+ case REFERENCE_TYPE:
+ error ("pointer value used where a floating point value was expected");
+ return convert_to_real (type, integer_zero_node);
+
+ default:
+ error ("aggregate value used where a float was expected");
+ return convert_to_real (type, integer_zero_node);
+ }
}
/* Convert EXPR to some integer (or enum) type TYPE.
- EXPR must be pointer, integer, discrete (enum, char, or bool), or float;
- in other cases error is called.
+ EXPR must be pointer, integer, discrete (enum, char, or bool), float, or
+ vector; in other cases error is called.
The result of this is always supposed to be a newly created tree node
not in use in any existing structure. */
convert_to_integer (type, expr)
tree type, expr;
{
- register tree intype = TREE_TYPE (expr);
- register enum tree_code form = TREE_CODE (intype);
+ enum tree_code ex_form = TREE_CODE (expr);
+ tree intype = TREE_TYPE (expr);
+ unsigned int inprec = TYPE_PRECISION (intype);
+ unsigned int outprec = TYPE_PRECISION (type);
+
+ /* An INTEGER_TYPE cannot be incomplete, but an ENUMERAL_TYPE can
+ be. Consider `enum E = { a, b = (enum E) 3 };'. */
+ if (!COMPLETE_TYPE_P (type))
+ {
+ error ("conversion to incomplete type");
+ return error_mark_node;
+ }
- if (form == POINTER_TYPE)
+ switch (TREE_CODE (intype))
{
+ case POINTER_TYPE:
+ case REFERENCE_TYPE:
if (integer_zerop (expr))
expr = integer_zero_node;
else
- expr = fold (build1 (CONVERT_EXPR,
- type_for_size (POINTER_SIZE, 0), expr));
- intype = TREE_TYPE (expr);
- form = TREE_CODE (intype);
- if (intype == type)
- return expr;
- }
+ expr = fold (build1 (CONVERT_EXPR, (*lang_hooks.types.type_for_size)
+ (POINTER_SIZE, 0), expr));
- if (form == INTEGER_TYPE || form == ENUMERAL_TYPE
- || form == BOOLEAN_TYPE || form == CHAR_TYPE)
- {
- register unsigned outprec = TYPE_PRECISION (type);
- register unsigned inprec = TYPE_PRECISION (intype);
- register enum tree_code ex_form = TREE_CODE (expr);
+ return convert_to_integer (type, expr);
- /* If we are widening the type, put in an explicit conversion.
- Similarly if we are not changing the width. However, if this is
- a logical operation that just returns 0 or 1, we can change the
- type of the expression (see below). */
-
- if (TREE_CODE_CLASS (ex_form) == '<'
- || ex_form == TRUTH_AND_EXPR || ex_form == TRUTH_ANDIF_EXPR
- || ex_form == TRUTH_OR_EXPR || ex_form == TRUTH_ORIF_EXPR
- || ex_form == TRUTH_XOR_EXPR || ex_form == TRUTH_NOT_EXPR)
+ case INTEGER_TYPE:
+ case ENUMERAL_TYPE:
+ case BOOLEAN_TYPE:
+ case CHAR_TYPE:
+ /* If this is a logical operation, which just returns 0 or 1, we can
+ change the type of the expression. For some logical operations,
+ we must also change the types of the operands to maintain type
+ correctness. */
+
+ if (TREE_CODE_CLASS (ex_form) == '<')
+ {
+ TREE_TYPE (expr) = type;
+ return expr;
+ }
+
+ else if (ex_form == TRUTH_AND_EXPR || ex_form == TRUTH_ANDIF_EXPR
+ || ex_form == TRUTH_OR_EXPR || ex_form == TRUTH_ORIF_EXPR
+ || ex_form == TRUTH_XOR_EXPR)
{
+ TREE_OPERAND (expr, 0) = convert (type, TREE_OPERAND (expr, 0));
+ TREE_OPERAND (expr, 1) = convert (type, TREE_OPERAND (expr, 1));
TREE_TYPE (expr) = type;
return expr;
}
+
+ else if (ex_form == TRUTH_NOT_EXPR)
+ {
+ TREE_OPERAND (expr, 0) = convert (type, TREE_OPERAND (expr, 0));
+ TREE_TYPE (expr) = type;
+ return expr;
+ }
+
+ /* If we are widening the type, put in an explicit conversion.
+ Similarly if we are not changing the width. After this, we know
+ we are truncating EXPR. */
+
else if (outprec >= inprec)
return build1 (NOP_EXPR, type, expr);
-/* Here detect when we can distribute the truncation down past some arithmetic.
- For example, if adding two longs and converting to an int,
- we can equally well convert both to ints and then add.
- For the operations handled here, such truncation distribution
- is always safe.
- It is desirable in these cases:
- 1) when truncating down to full-word from a larger size
- 2) when truncating takes no work.
- 3) when at least one operand of the arithmetic has been extended
- (as by C's default conversions). In this case we need two conversions
- if we do the arithmetic as already requested, so we might as well
- truncate both and then combine. Perhaps that way we need only one.
-
- Note that in general we cannot do the arithmetic in a type
- shorter than the desired result of conversion, even if the operands
- are both extended from a shorter type, because they might overflow
- if combined in that type. The exceptions to this--the times when
- two narrow values can be combined in their narrow type even to
- make a wider result--are handled by "shorten" in build_binary_op. */
+ /* If TYPE is an enumeral type or a type with a precision less
+ than the number of bits in its mode, do the conversion to the
+ type corresponding to its mode, then do a nop conversion
+ to TYPE. */
+ else if (TREE_CODE (type) == ENUMERAL_TYPE
+ || outprec != GET_MODE_BITSIZE (TYPE_MODE (type)))
+ return build1 (NOP_EXPR, type,
+ convert ((*lang_hooks.types.type_for_mode)
+ (TYPE_MODE (type), TREE_UNSIGNED (type)),
+ expr));
+
+ /* Here detect when we can distribute the truncation down past some
+ arithmetic. For example, if adding two longs and converting to an
+ int, we can equally well convert both to ints and then add.
+ For the operations handled here, such truncation distribution
+ is always safe.
+ It is desirable in these cases:
+ 1) when truncating down to full-word from a larger size
+ 2) when truncating takes no work.
+ 3) when at least one operand of the arithmetic has been extended
+ (as by C's default conversions). In this case we need two conversions
+ if we do the arithmetic as already requested, so we might as well
+ truncate both and then combine. Perhaps that way we need only one.
+
+ Note that in general we cannot do the arithmetic in a type
+ shorter than the desired result of conversion, even if the operands
+ are both extended from a shorter type, because they might overflow
+ if combined in that type. The exceptions to this--the times when
+ two narrow values can be combined in their narrow type even to
+ make a wider result--are handled by "shorten" in build_binary_op. */
switch (ex_form)
{
/* We can pass truncation down through right shifting
when the shift count is a nonpositive constant. */
if (TREE_CODE (TREE_OPERAND (expr, 1)) == INTEGER_CST
- && tree_int_cst_lt (TREE_OPERAND (expr, 1), integer_one_node))
+ && tree_int_cst_lt (TREE_OPERAND (expr, 1),
+ convert (TREE_TYPE (TREE_OPERAND (expr, 1)),
+ integer_one_node)))
goto trunc1;
break;
/* We can pass truncation down through left shifting
when the shift count is a nonnegative constant. */
if (TREE_CODE (TREE_OPERAND (expr, 1)) == INTEGER_CST
- && ! tree_int_cst_lt (TREE_OPERAND (expr, 1), integer_zero_node)
+ && tree_int_cst_sgn (TREE_OPERAND (expr, 1)) >= 0
&& TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST)
{
/* If shift count is less than the width of the truncated type,
/* In this case, shifting is like multiplication. */
goto trunc1;
else
- /* If it is >= that width, result is zero.
- Handling this with trunc1 would give the wrong result:
- (int) ((long long) a << 32) is well defined (as 0)
- but (int) a << 32 is undefined and would get a warning. */
- return convert_to_integer (type, integer_zero_node);
+ {
+ /* If it is >= that width, result is zero.
+ Handling this with trunc1 would give the wrong result:
+ (int) ((long long) a << 32) is well defined (as 0)
+ but (int) a << 32 is undefined and would get a
+ warning. */
+
+ tree t = convert_to_integer (type, integer_zero_node);
+
+ /* If the original expression had side-effects, we must
+ preserve it. */
+ if (TREE_SIDE_EFFECTS (expr))
+ return build (COMPOUND_EXPR, type, expr, t);
+ else
+ return t;
+ }
}
break;
{
/* Do the arithmetic in type TYPEX,
then convert result to TYPE. */
- register tree typex = type;
+ tree typex = type;
/* Can't do arithmetic in enumeral types
so use an integer type that will hold the values. */
if (TREE_CODE (typex) == ENUMERAL_TYPE)
- typex = type_for_size (TYPE_PRECISION (typex),
- TREE_UNSIGNED (typex));
+ typex = (*lang_hooks.types.type_for_size)
+ (TYPE_PRECISION (typex), TREE_UNSIGNED (typex));
/* But now perhaps TYPEX is as wide as INPREC.
In that case, do nothing special here.
{
/* Don't do unsigned arithmetic where signed was wanted,
or vice versa.
- Exception: if either of the original operands were
+ Exception: if both of the original operands were
unsigned then can safely do the work as unsigned.
And we may need to do it as unsigned
if we truncate to the original size. */
- typex = ((TREE_UNSIGNED (TREE_TYPE (expr))
- || TREE_UNSIGNED (TREE_TYPE (arg0))
- || TREE_UNSIGNED (TREE_TYPE (arg1)))
- ? unsigned_type (typex) : signed_type (typex));
+ if (TREE_UNSIGNED (TREE_TYPE (expr))
+ || (TREE_UNSIGNED (TREE_TYPE (arg0))
+ && TREE_UNSIGNED (TREE_TYPE (arg1))))
+ typex = (*lang_hooks.types.unsigned_type) (typex);
+ else
+ typex = (*lang_hooks.types.signed_type) (typex);
return convert (type,
- build_binary_op (ex_form,
- convert (typex, arg0),
- convert (typex, arg1),
- 0));
+ fold (build (ex_form, typex,
+ convert (typex, arg0),
+ convert (typex, arg1),
+ 0)));
}
}
}
case NEGATE_EXPR:
case BIT_NOT_EXPR:
- case ABS_EXPR:
+ /* This is not correct for ABS_EXPR,
+ since we must test the sign before truncation. */
{
- register tree typex = type;
+ tree typex = type;
/* Can't do arithmetic in enumeral types
so use an integer type that will hold the values. */
if (TREE_CODE (typex) == ENUMERAL_TYPE)
- typex = type_for_size (TYPE_PRECISION (typex),
- TREE_UNSIGNED (typex));
+ typex = (*lang_hooks.types.type_for_size)
+ (TYPE_PRECISION (typex), TREE_UNSIGNED (typex));
/* But now perhaps TYPEX is as wide as INPREC.
In that case, do nothing special here.
{
/* Don't do unsigned arithmetic where signed was wanted,
or vice versa. */
- typex = (TREE_UNSIGNED (TREE_TYPE (expr))
- ? unsigned_type (typex) : signed_type (typex));
+ if (TREE_UNSIGNED (TREE_TYPE (expr)))
+ typex = (*lang_hooks.types.unsigned_type) (typex);
+ else
+ typex = (*lang_hooks.types.signed_type) (typex);
return convert (type,
- build_unary_op (ex_form,
- convert (typex, TREE_OPERAND (expr, 0)),
- 1));
+ fold (build1 (ex_form, typex,
+ convert (typex,
+ TREE_OPERAND (expr, 0)))));
}
}
return convert (type, get_unwidened (TREE_OPERAND (expr, 0), type));
case COND_EXPR:
- /* Can treat the two alternative values like the operands
- of an arithmetic expression. */
- {
- tree arg1 = get_unwidened (TREE_OPERAND (expr, 1), type);
- tree arg2 = get_unwidened (TREE_OPERAND (expr, 2), type);
-
- if (outprec >= BITS_PER_WORD
- || TRULY_NOOP_TRUNCATION (outprec, inprec)
- || inprec > TYPE_PRECISION (TREE_TYPE (arg1))
- || inprec > TYPE_PRECISION (TREE_TYPE (arg2)))
- {
- /* Do the arithmetic in type TYPEX,
- then convert result to TYPE. */
- register tree typex = type;
-
- /* Can't do arithmetic in enumeral types
- so use an integer type that will hold the values. */
- if (TREE_CODE (typex) == ENUMERAL_TYPE)
- typex = type_for_size (TYPE_PRECISION (typex),
- TREE_UNSIGNED (typex));
-
- /* But now perhaps TYPEX is as wide as INPREC.
- In that case, do nothing special here.
- (Otherwise would recurse infinitely in convert. */
- if (TYPE_PRECISION (typex) != inprec)
- {
- /* Don't do unsigned arithmetic where signed was wanted,
- or vice versa. */
- typex = (TREE_UNSIGNED (TREE_TYPE (expr))
- ? unsigned_type (typex) : signed_type (typex));
- return convert (type,
- fold (build (COND_EXPR, typex,
- TREE_OPERAND (expr, 0),
- convert (typex, arg1),
- convert (typex, arg2))));
- }
- else
- /* It is sometimes worthwhile
- to push the narrowing down through the conditional. */
- return fold (build (COND_EXPR, type,
- TREE_OPERAND (expr, 0),
- convert (type, TREE_OPERAND (expr, 1)),
- convert (type, TREE_OPERAND (expr, 2))));
- }
- }
+ /* It is sometimes worthwhile to push the narrowing down through
+ the conditional and never loses. */
+ return fold (build (COND_EXPR, type, TREE_OPERAND (expr, 0),
+ convert (type, TREE_OPERAND (expr, 1)),
+ convert (type, TREE_OPERAND (expr, 2))));
+ default:
+ break;
}
return build1 (NOP_EXPR, type, expr);
- }
- if (form == REAL_TYPE)
- return build1 (FIX_TRUNC_EXPR, type, expr);
+ case REAL_TYPE:
+ return build1 (FIX_TRUNC_EXPR, type, expr);
- if (form == COMPLEX_TYPE)
- return convert (type, fold (build1 (REALPART_EXPR,
- TREE_TYPE (TREE_TYPE (expr)), expr)));
+ case COMPLEX_TYPE:
+ return convert (type,
+ fold (build1 (REALPART_EXPR,
+ TREE_TYPE (TREE_TYPE (expr)), expr)));
- error ("aggregate value used where an integer was expected");
+ case VECTOR_TYPE:
+ if (GET_MODE_SIZE (TYPE_MODE (type))
+ != GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (expr))))
+ {
+ error ("can't convert between vector values of different size");
+ return error_mark_node;
+ }
+ return build1 (NOP_EXPR, type, expr);
- {
- register tree tem = build_int_2 (0, 0);
- TREE_TYPE (tem) = type;
- return tem;
- }
+ default:
+ error ("aggregate value used where an integer was expected");
+ return convert (type, integer_zero_node);
+ }
}
/* Convert EXPR to the complex type TYPE in the usual ways. */
convert_to_complex (type, expr)
tree type, expr;
{
- register enum tree_code form = TREE_CODE (TREE_TYPE (expr));
tree subtype = TREE_TYPE (type);
- if (form == REAL_TYPE || form == INTEGER_TYPE || form == ENUMERAL_TYPE)
+ switch (TREE_CODE (TREE_TYPE (expr)))
{
- expr = convert (subtype, expr);
- return build (COMPLEX_EXPR, type, expr,
+ case REAL_TYPE:
+ case INTEGER_TYPE:
+ case ENUMERAL_TYPE:
+ case BOOLEAN_TYPE:
+ case CHAR_TYPE:
+ return build (COMPLEX_EXPR, type, convert (subtype, expr),
convert (subtype, integer_zero_node));
+
+ case COMPLEX_TYPE:
+ {
+ tree elt_type = TREE_TYPE (TREE_TYPE (expr));
+
+ if (TYPE_MAIN_VARIANT (elt_type) == TYPE_MAIN_VARIANT (subtype))
+ return expr;
+ else if (TREE_CODE (expr) == COMPLEX_EXPR)
+ return fold (build (COMPLEX_EXPR,
+ type,
+ convert (subtype, TREE_OPERAND (expr, 0)),
+ convert (subtype, TREE_OPERAND (expr, 1))));
+ else
+ {
+ expr = save_expr (expr);
+ return
+ fold (build (COMPLEX_EXPR,
+ type, convert (subtype,
+ fold (build1 (REALPART_EXPR,
+ TREE_TYPE (TREE_TYPE (expr)),
+ expr))),
+ convert (subtype,
+ fold (build1 (IMAGPART_EXPR,
+ TREE_TYPE (TREE_TYPE (expr)),
+ expr)))));
+ }
+ }
+
+ case POINTER_TYPE:
+ case REFERENCE_TYPE:
+ error ("pointer value used where a complex was expected");
+ return convert_to_complex (type, integer_zero_node);
+
+ default:
+ error ("aggregate value used where a complex was expected");
+ return convert_to_complex (type, integer_zero_node);
}
+}
+
+/* Convert EXPR to the vector type TYPE in the usual ways. */
- if (form == COMPLEX_TYPE)
+tree
+convert_to_vector (type, expr)
+ tree type, expr;
+{
+ switch (TREE_CODE (TREE_TYPE (expr)))
{
- tree elt_type = TREE_TYPE (TREE_TYPE (expr));
- if (TYPE_MAIN_VARIANT (elt_type) == TYPE_MAIN_VARIANT (subtype))
- return expr;
- else if (TREE_CODE (expr) == COMPLEX_EXPR)
- return fold (build (COMPLEX_EXPR,
- type,
- convert (subtype, TREE_OPERAND (expr, 0)),
- convert (subtype, TREE_OPERAND (expr, 1))));
- else
+ case INTEGER_TYPE:
+ case VECTOR_TYPE:
+ if (GET_MODE_SIZE (TYPE_MODE (type))
+ != GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (expr))))
{
- expr = save_expr (expr);
- return fold (build (COMPLEX_EXPR,
- type,
- convert (subtype,
- build_unary_op (REALPART_EXPR, expr, 1)),
- convert (subtype,
- build_unary_op (IMAGPART_EXPR, expr, 1))));
+ error ("can't convert between vector values of different size");
+ return error_mark_node;
}
- }
+ return build1 (NOP_EXPR, type, expr);
- if (form == POINTER_TYPE)
- error ("pointer value used where a complex was expected");
- else
- error ("aggregate value used where a complex was expected");
-
- return build (COMPLEX_EXPR, type,
- convert (subtype, integer_zero_node),
- convert (subtype, integer_zero_node));
+ default:
+ error ("can't convert value to a vector");
+ return convert_to_vector (type, integer_zero_node);
+ }
}
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