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/*
Crown Copyright (c) 1997
This TenDRA(r) Computer Program is subject to Copyright
owned by the United Kingdom Secretary of State for Defence
acting through the Defence Evaluation and Research Agency
(DERA). It is made available to Recipients with a
royalty-free licence for its use, reproduction, transfer
to other parties and amendment for any purpose not excluding
product development provided that any such use et cetera
shall be deemed to be acceptance of the following conditions:-
(1) Its Recipients shall ensure that this Notice is
reproduced upon any copies or amended versions of it;
(2) Any amended version of it shall be clearly marked to
show both the nature of and the organisation responsible
for the relevant amendment or amendments;
(3) Its onward transfer from a recipient to another
party shall be deemed to be that party's acceptance of
these conditions;
(4) DERA gives no warranty or assurance as to its
quality or suitability for any purpose and DERA accepts
no liability whatsoever in relation to any use to which
it may be put.
*/
#include "config.h"
#include "c_types.h"
#include "exp_ops.h"
#include "id_ops.h"
#include "off_ops.h"
#include "type_ops.h"
#include "error.h"
#include "catalog.h"
#include "assign.h"
#include "basetype.h"
#include "cast.h"
#include "construct.h"
#include "convert.h"
#include "chktype.h"
#include "expression.h"
#include "identifier.h"
#include "initialise.h"
#include "literal.h"
#include "member.h"
#include "operator.h"
#include "predict.h"
#include "syntax.h"
#include "ustring.h"
/*
CONVERT BY ASSIGNMENT
This routine converts the expression a to the type t, as if by
assignment. The cases where t is a class type or a reference are
handled elsewhere.
*/
EXP convert_assign
PROTO_N ( ( t, a, err ) )
PROTO_T ( TYPE t X EXP a X ERROR *err )
{
EXP e = cast_exp ( t, a, err, CAST_IMPLICIT ) ;
return ( e ) ;
}
/*
CONVERT TO A CLASS TYPE BY ASSIGNMENT
This routine converts the expression a to the class t, as if by
assignment. The constructors of t are ignored, only base class
conversions and conversion operators being considered.
*/
EXP convert_class
PROTO_N ( ( t, a, err ) )
PROTO_T ( TYPE t X EXP a X ERROR *err )
{
EXP e ;
TYPE s = DEREF_type ( exp_type ( a ) ) ;
if ( IS_type_compound ( s ) ) {
e = cast_class_class ( t, a, err, CAST_IMPLICIT, 0 ) ;
if ( !IS_NULL_exp ( e ) ) return ( e ) ;
}
e = convert_conv ( t, a, err, CAST_IMPLICIT ) ;
return ( e ) ;
}
/*
CONSTRUCT A POSTFIX EXPRESSION
This routine constructs the expressions 'a++' and 'a--'. Note that
in this and other assignment expressions, a cannot have array type,
so that no bounds checks are appropriate. The result is an rvalue.
*/
EXP make_postfix_exp
PROTO_N ( ( op, a ) )
PROTO_T ( int op X EXP a )
{
EXP e ;
TYPE ta ;
ERROR err ;
unsigned ca ;
/* An assignment is a side effect */
no_side_effects++ ;
/* Allow for reference conversions */
a = convert_reference ( a, REF_NORMAL ) ;
ta = DEREF_type ( exp_type ( a ) ) ;
ca = type_category ( &ta ) ;
/* Check for overloading */
#if LANGUAGE_CPP
if ( IS_TYPE_OVERLOAD ( ca ) ) {
if ( overload_depth == 0 ) {
/* Overloads as 'operator op ( a, 0 )' */
EXP b = make_null_exp ( type_sint ) ;
e = binary_overload ( op, a, b ) ;
return ( e ) ;
}
if ( IS_TYPE_CLASS ( ca ) ) goto error_lab ;
}
#else
if ( IS_TYPE_CLASS ( ca ) ) goto error_lab ;
#endif
/* Operand should be a modifiable lvalue */
err = check_modifiable ( ta, a ) ;
if ( !IS_NULL_err ( err ) ) {
err = concat_error ( err, ERR_expr_post_incr_mod ( op ) ) ;
report ( crt_loc, err ) ;
err = NULL_err ;
}
/* Operand can be arithmetic ... */
if ( IS_TYPE_ARITH ( ca ) ) {
EXP b ;
TYPE t ;
TYPE tb ;
OFFSET off = NULL_off ;
/* Allow for bitfields */
if ( IS_TYPE_BITF ( ca ) ) off = decons_bitf_exp ( &a ) ;
/* Form the result */
MAKE_exp_dummy ( ta, a, LINK_NONE, off, 0, a ) ;
b = convert_lvalue ( a ) ;
tb = DEREF_type ( exp_type ( b ) ) ;
t = promote_type ( tb ) ;
if ( IS_NULL_off ( off ) ) {
MAKE_exp_dummy ( tb, b, LINK_NONE, NULL_off, 0, b ) ;
e = convert_promote ( t, b ) ;
} else {
b = convert_promote ( t, b ) ;
MAKE_exp_dummy ( t, b, LINK_NONE, NULL_off, 0, b ) ;
e = b ;
tb = t ;
}
if ( check_int_type ( ta, btype_bool ) ) {
/* Booleans are weird */
unsigned v = BOOL_TRUE ;
if ( op == lex_plus_Hplus ) {
report ( crt_loc, ERR_expr_post_incr_bool_inc ( op, ta ) ) ;
} else {
report ( crt_loc, ERR_expr_post_incr_bool_dec ( op, ta ) ) ;
v = BOOL_FALSE ;
}
e = make_bool_exp ( v, exp_int_lit_tag ) ;
} else {
/* Other types are simple */
EXP c = make_unit_exp ( t ) ;
if ( op == lex_plus_Hplus ) {
MAKE_exp_plus ( t, e, c, e ) ;
} else {
MAKE_exp_minus ( t, e, c, e ) ;
}
e = convert_assign ( ta, e, &err ) ;
if ( !IS_NULL_err ( err ) ) {
err = concat_warning ( err, ERR_expr_ass_conv () ) ;
report ( crt_loc, err ) ;
}
}
MAKE_exp_postinc ( tb, a, b, e, e ) ;
return ( e ) ;
}
/* ... or pointer ... */
if ( IS_TYPE_PTR ( ca ) ) {
/* Pointer must be to complete object type */
EXP b ;
OFFSET off ;
TYPE t = check_pointer ( ta, &err ) ;
if ( !IS_NULL_err ( err ) ) {
err = concat_error ( err, ERR_expr_post_incr_incompl ( op ) ) ;
report ( crt_loc, err ) ;
}
if ( IS_type_top_etc ( t ) ) t = type_char ;
/* Create the identities */
MAKE_exp_dummy ( ta, a, LINK_NONE, NULL_off, 0, a ) ;
b = convert_lvalue ( a ) ;
ta = DEREF_type ( exp_type ( b ) ) ;
MAKE_exp_dummy ( ta, b, LINK_NONE, NULL_off, 0, b ) ;
/* Form the result */
MAKE_off_type ( t, off ) ;
if ( op == lex_minus_Hminus ) MAKE_off_negate ( off, off ) ;
e = make_add_ptr ( ta, b, off ) ;
MAKE_exp_postinc ( ta, a, b, e, e ) ;
return ( e ) ;
}
/* ... and nothing else */
error_lab : {
if ( !IS_TYPE_ERROR ( ca ) ) {
report ( crt_loc, ERR_expr_post_incr_op ( op, ta ) ) ;
}
}
e = make_error_exp ( 0 ) ;
return ( e ) ;
}
/*
CREATE A PRE-INCREMENT EXPRESSION
This routine creates a pre-increment or assignment expression for
the expression a of type t given by the operation b. If a is a
bitfield then off gives the bitfield offset. The result is an
lvalue in C++, but an rvalue in C. There is a slight problem in the
latter case when t is a bitfield: the value is not b, but
convert_bitfield ( b ). This conversion is left implicit, and is
only made explicit in the TDF output routines.
*/
static EXP make_preinc_exp
PROTO_N ( ( t, a, b, off, op ) )
PROTO_T ( TYPE t X EXP a X EXP b X OFFSET off X int op )
{
EXP e ;
#if LANGUAGE_C
t = rvalue_type ( t ) ;
#endif
if ( IS_NULL_off ( off ) ) {
/* Simple case */
if ( op == lex_assign ) {
MAKE_exp_assign ( t, a, b, e ) ;
} else {
MAKE_exp_preinc ( t, a, b, op, e ) ;
}
} else {
/* Bitfield case */
#if LANGUAGE_C
MAKE_exp_preinc ( t, a, b, op, e ) ;
t = promote_type ( t ) ;
#else
TYPE p ;
TYPE s = find_bitfield_type ( t ) ;
MAKE_type_ptr ( cv_none, s, p ) ;
s = lvalue_type ( s ) ;
MAKE_exp_preinc ( s, a, b, op, e ) ;
MAKE_exp_address ( p, e, e ) ;
MAKE_exp_add_ptr ( p, e, off, 0, e ) ;
MAKE_exp_indir ( t, e, e ) ;
#endif
}
#if LANGUAGE_C
MAKE_exp_contents ( t, e, e ) ;
#endif
return ( e ) ;
}
/*
CONSTRUCT A PREFIX EXPRESSION
This routine constructs the expressions '++a' and '--a'. The result is
an lvalue in C++ but an rvalue in C.
*/
EXP make_prefix_exp
PROTO_N ( ( op, a ) )
PROTO_T ( int op X EXP a )
{
EXP e ;
TYPE ta ;
ERROR err ;
unsigned ca ;
/* An assignment is a side effect */
no_side_effects++ ;
/* Allow for reference conversions */
a = convert_reference ( a, REF_NORMAL ) ;
ta = DEREF_type ( exp_type ( a ) ) ;
ca = type_category ( &ta ) ;
/* Check for overloading */
#if LANGUAGE_CPP
if ( IS_TYPE_OVERLOAD ( ca ) ) {
if ( overload_depth == 0 ) {
/* Overloads as 'operator op ( a )' */
e = unary_overload ( op, a ) ;
return ( e ) ;
}
if ( IS_TYPE_CLASS ( ca ) ) goto error_lab ;
}
#else
if ( IS_TYPE_CLASS ( ca ) ) goto error_lab ;
#endif
/* Operand should be a modifiable lvalue */
err = check_modifiable ( ta, a ) ;
if ( !IS_NULL_err ( err ) ) {
err = concat_error ( err, ERR_expr_pre_incr_mod ( op ) ) ;
report ( crt_loc, err ) ;
err = NULL_err ;
}
/* Operand can be arithmetic ... */
if ( IS_TYPE_ARITH ( ca ) ) {
EXP c ;
TYPE t ;
OFFSET off = NULL_off ;
/* Booleans are weird */
if ( check_int_type ( ta, btype_bool ) ) {
unsigned v = BOOL_TRUE ;
if ( op == lex_plus_Hplus ) {
report ( crt_loc, ERR_expr_pre_incr_bool_inc ( op, ta ) ) ;
} else {
report ( crt_loc, ERR_expr_pre_incr_bool_dec ( op, ta ) ) ;
v = BOOL_FALSE ;
}
c = make_bool_exp ( v, exp_int_lit_tag ) ;
e = make_preinc_exp ( ta, a, c, NULL_off, lex_assign ) ;
return ( e ) ;
}
/* Allow for bitfields */
if ( IS_TYPE_BITF ( ca ) ) off = decons_bitf_exp ( &a ) ;
/* Form the result */
MAKE_exp_dummy ( ta, a, LINK_NONE, off, 0, a ) ;
e = convert_lvalue ( a ) ;
t = DEREF_type ( exp_type ( e ) ) ;
t = promote_type ( t ) ;
e = convert_promote ( t, e ) ;
c = make_unit_exp ( t ) ;
if ( op == lex_plus_Hplus ) {
MAKE_exp_plus ( t, e, c, e ) ;
} else {
MAKE_exp_minus ( t, e, c, e ) ;
}
e = convert_assign ( ta, e, &err ) ;
if ( !IS_NULL_err ( err ) ) {
err = concat_warning ( err, ERR_expr_ass_conv () ) ;
report ( crt_loc, err ) ;
}
e = make_preinc_exp ( ta, a, e, off, op ) ;
return ( e ) ;
}
/* ... or pointer ... */
if ( IS_TYPE_PTR ( ca ) ) {
/* Pointer must be to complete object type */
OFFSET off ;
TYPE t = check_pointer ( ta, &err ) ;
if ( !IS_NULL_err ( err ) ) {
err = concat_error ( err, ERR_expr_pre_incr_incompl ( op ) ) ;
report ( crt_loc, err ) ;
}
if ( IS_type_top_etc ( t ) ) t = type_char ;
/* Form the result */
MAKE_exp_dummy ( ta, a, LINK_NONE, NULL_off, 0, a ) ;
e = convert_lvalue ( a ) ;
if ( !IS_type_ptr ( ta ) ) ta = DEREF_type ( exp_type ( e ) ) ;
MAKE_off_type ( t, off ) ;
if ( op == lex_minus_Hminus ) MAKE_off_negate ( off, off ) ;
e = make_add_ptr ( ta, e, off ) ;
e = make_preinc_exp ( ta, a, e, NULL_off, op ) ;
return ( e ) ;
}
/* ... and nothing else */
error_lab : {
if ( !IS_TYPE_ERROR ( ca ) ) {
report ( crt_loc, ERR_expr_pre_incr_op ( op, ta ) ) ;
}
e = make_error_exp ( LANGUAGE_CPP ) ;
return ( e ) ;
}
}
/*
CONSTRUCT AN ASSIGNMENT EXPRESSION
This routine constructs the expression 'a = b'. If c is true then
assignment of classes is done directly rather than via an assignment
operator. The result is an lvalue in C++ but an rvalue in C.
*/
EXP make_assign_exp
PROTO_N ( ( a, b, c ) )
PROTO_T ( EXP a X EXP b X int c )
{
EXP e ;
ERROR err ;
TYPE ta, tb ;
unsigned ca, cb ;
int to_class = 0 ;
int op = lex_assign ;
OFFSET off = NULL_off ;
/* An assignment is a side effect */
no_side_effects++ ;
/* Apply reference conversion on first operand */
a = convert_reference ( a, REF_NORMAL ) ;
ta = DEREF_type ( exp_type ( a ) ) ;
ca = type_category ( &ta ) ;
/* Apply reference conversion on second operand */
b = convert_reference ( b, REF_ASSIGN ) ;
tb = DEREF_type ( exp_type ( b ) ) ;
cb = type_category ( &tb ) ;
/* Check for template parameters */
#if LANGUAGE_CPP
if ( IS_TYPE_TEMPL ( ca ) || IS_TYPE_TEMPL ( cb ) ) {
if ( overload_depth == 0 ) {
e = binary_overload ( op, a, b ) ;
return ( e ) ;
}
}
#endif
/* Check for overloading (classes only) */
if ( IS_TYPE_CLASS ( ca ) ) {
#if LANGUAGE_CPP
if ( c == 0 ) {
if ( overload_depth == 0 ) {
e = binary_overload ( op, a, b ) ;
return ( e ) ;
}
if ( !IS_TYPE_ERROR ( cb ) ) {
/* Find reason for failure */
err = check_incomplete ( ta ) ;
if ( IS_NULL_err ( err ) && IS_type_compound ( ta ) ) {
CLASS_TYPE ct ;
IDENTIFIER id ;
ct = DEREF_ctype ( type_compound_defn ( ta ) ) ;
id = find_operator ( ct, op ) ;
if ( !IS_NULL_id ( id ) ) {
err = ERR_over_match_viable_none ( id ) ;
}
}
err = concat_error ( err, ERR_expr_ass_op ( op, ta, tb ) ) ;
report ( crt_loc, err ) ;
}
e = make_error_exp ( LANGUAGE_CPP ) ;
return ( e ) ;
}
#else
UNUSED ( c ) ;
UNUSED ( cb ) ;
#endif
to_class = 1 ;
}
/* First operand should be a modifiable lvalue */
err = check_modifiable ( ta, a ) ;
if ( !IS_NULL_err ( err ) ) {
err = concat_error ( err, ERR_expr_ass_mod ( op ) ) ;
report ( crt_loc, err ) ;
}
/* Do operand conversion */
err = NULL_err ;
if ( to_class ) {
b = convert_none ( b ) ;
b = convert_class ( ta, b, &err ) ;
b = remove_temporary ( b, a ) ;
} else {
b = convert_assign ( ta, b, &err ) ;
}
if ( !IS_NULL_err ( err ) ) {
err = concat_warning ( err, ERR_expr_ass_conv () ) ;
report ( crt_loc, err ) ;
}
/* Construct the result */
if ( IS_type_bitfield ( ta ) ) {
off = decons_bitf_exp ( &a ) ;
MAKE_exp_dummy ( ta, a, LINK_NONE, off, 0, a ) ;
}
e = make_preinc_exp ( ta, a, b, off, op ) ;
return ( e ) ;
}
/*
CONSTRUCT A BECOMES EXPRESSION
This routine constructs the expression 'a op b' where op is one of the
assignment operators, '*=', '/=' etc. The result is an lvalue in
C++, but an rvalue in C.
*/
EXP make_become_exp
PROTO_N ( ( op, a, b ) )
PROTO_T ( int op X EXP a X EXP b )
{
EXP e ;
EXP d ;
TYPE td ;
ERROR err ;
TYPE ta, tb ;
unsigned tag ;
unsigned ca, cb ;
OFFSET off = NULL_off ;
/* An assignment is a side effect */
no_side_effects++ ;
/* Apply reference conversion on first operand */
a = convert_reference ( a, REF_NORMAL ) ;
ta = DEREF_type ( exp_type ( a ) ) ;
ca = type_category ( &ta ) ;
/* Apply reference conversion on second operand */
b = convert_reference ( b, REF_NORMAL ) ;
tb = DEREF_type ( exp_type ( b ) ) ;
cb = type_category ( &tb ) ;
/* Allow for overloading */
#if LANGUAGE_CPP
if ( IS_TYPE_OVERLOAD ( ca ) || IS_TYPE_OVERLOAD ( cb ) ) {
if ( overload_depth == 0 ) {
e = binary_overload ( op, a, b ) ;
return ( e ) ;
}
if ( IS_TYPE_CLASS ( ca ) ) goto error_lab ;
}
#else
if ( IS_TYPE_CLASS ( ca ) ) goto error_lab ;
#endif
/* First operand should be a modifiable lvalue */
err = check_modifiable ( ta, a ) ;
if ( !IS_NULL_err ( err ) ) {
err = concat_error ( err, ERR_expr_ass_mod ( op ) ) ;
report ( crt_loc, err ) ;
err = NULL_err ;
}
/* Allow for bitfields */
if ( IS_TYPE_BITF ( ca ) ) off = decons_bitf_exp ( &a ) ;
/* Introduce identity for assignment variable */
td = ta ;
MAKE_exp_dummy ( td, a, LINK_NONE, off, 0, d ) ;
a = convert_lvalue ( d ) ;
ta = DEREF_type ( exp_type ( a ) ) ;
ca = type_category ( &ta ) ;
/* Do lvalue conversions */
if ( IS_TYPE_ADDRESS ( cb ) ) {
b = convert_lvalue ( b ) ;
tb = DEREF_type ( exp_type ( b ) ) ;
cb = type_category ( &tb ) ;
}
/* Weed out booleans immediately */
if ( IS_TYPE_INT ( ca ) && check_int_type ( ta, btype_bool ) ) {
report ( crt_loc, ERR_expr_ass_op ( op, ta, tb ) ) ;
e = make_error_exp ( LANGUAGE_CPP ) ;
return ( e ) ;
}
/* Find the operation type */
switch ( op ) {
case lex_and_Heq_H1 : tag = exp_and_tag ; goto integral_lab ;
case lex_div_Heq : tag = exp_div_tag ; goto arithmetic_lab ;
case lex_lshift_Heq : tag = exp_lshift_tag ; goto shift_lab ;
case lex_minus_Heq : tag = exp_minus_tag ; goto pointer_lab ;
case lex_or_Heq_H1 : tag = exp_or_tag ; goto integral_lab ;
case lex_plus_Heq : tag = exp_plus_tag ; goto pointer_lab ;
case lex_rem_Heq : tag = exp_rem_tag ; goto integral_lab ;
case lex_rshift_Heq : tag = exp_rshift_tag ; goto shift_lab ;
case lex_star_Heq : tag = exp_mult_tag ; goto arithmetic_lab ;
case lex_xor_Heq_H1 : tag = exp_xor_tag ; goto integral_lab ;
default : goto error_lab ;
}
integral_lab : {
/* Integral operations */
if ( IS_TYPE_INT ( ca ) && IS_TYPE_INT ( cb ) ) {
TYPE t = arith_type ( ta, tb, a, b ) ;
a = convert_arith ( t, a, op, 1 ) ;
b = convert_arith ( t, b, op, 2 ) ;
if ( op == lex_rem_Heq ) {
IGNORE check_div_exp ( op, a, b ) ;
}
MAKE_exp_plus_etc ( tag, t, a, b, e ) ;
e = convert_assign ( td, e, &err ) ;
if ( !IS_NULL_err ( err ) ) {
err = concat_warning ( err, ERR_expr_ass_conv () ) ;
report ( crt_loc, err ) ;
}
e = make_preinc_exp ( td, d, e, off, op ) ;
return ( e ) ;
}
goto error_lab ;
}
arithmetic_lab : {
/* Arithmetic operations */
if ( IS_TYPE_ARITH ( ca ) && IS_TYPE_ARITH ( cb ) ) {
TYPE t = arith_type ( ta, tb, a, b ) ;
a = convert_arith ( t, a, op, 1 ) ;
b = convert_arith ( t, b, op, 2 ) ;
if ( op == lex_div_Heq ) {
IGNORE check_div_exp ( op, a, b ) ;
}
MAKE_exp_plus_etc ( tag, t, a, b, e ) ;
e = convert_assign ( td, e, &err ) ;
if ( !IS_NULL_err ( err ) ) {
err = concat_warning ( err, ERR_expr_ass_conv () ) ;
report ( crt_loc, err ) ;
}
e = make_preinc_exp ( td, d, e, off, op ) ;
return ( e ) ;
}
goto error_lab ;
}
shift_lab : {
/* Shift operations */
if ( IS_TYPE_INT ( ca ) && IS_TYPE_INT ( cb ) ) {
TYPE pta = promote_type ( ta ) ;
TYPE ptb = promote_type ( tb ) ;
a = convert_promote ( pta, a ) ;
b = convert_promote ( ptb, b ) ;
IGNORE check_shift_exp ( op, pta, a, b ) ;
MAKE_exp_plus_etc ( tag, pta, a, b, e ) ;
e = convert_assign ( td, e, &err ) ;
if ( !IS_NULL_err ( err ) ) {
err = concat_warning ( err, ERR_expr_ass_conv () ) ;
report ( crt_loc, err ) ;
}
e = make_preinc_exp ( td, d, e, off, op ) ;
return ( e ) ;
}
goto error_lab ;
}
pointer_lab : {
/* Pointer or arithmetic operations */
if ( IS_TYPE_PTR ( ca ) && IS_TYPE_INT ( cb ) ) {
OFFSET off1 ;
int neg = 0 ;
TYPE t = check_pointer ( ta, &err ) ;
if ( !IS_NULL_err ( err ) ) {
err = concat_error ( err, ERR_expr_ass_incompl ( op ) ) ;
report ( crt_loc, err ) ;
}
if ( op == lex_minus_Heq ) neg = 1 ;
off1 = make_off_mult ( t, b, neg ) ;
e = make_add_ptr ( ta, a, off1 ) ;
e = make_preinc_exp ( td, d, e, NULL_off, op ) ;
return ( e ) ;
}
goto arithmetic_lab ;
}
error_lab : {
/* Bad operations */
if ( !IS_TYPE_ERROR ( ca ) && !IS_TYPE_ERROR ( cb ) ) {
report ( crt_loc, ERR_expr_ass_op ( op, ta, tb ) ) ;
}
e = make_error_exp ( LANGUAGE_CPP ) ;
return ( e ) ;
}
}