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/*

 * Copyright (c) 2002-2005 The TenDRA Project <http://www.tendra.org/>.

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions are met:

 *

 * 1. Redistributions of source code must retain the above copyright notice,

 *    this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright notice,

 *    this list of conditions and the following disclaimer in the documentation

 *    and/or other materials provided with the distribution.

 * 3. Neither the name of The TenDRA Project nor the names of its contributors

 *    may be used to endorse or promote products derived from this software

 *    without specific, prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS

 * IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,

 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR

 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

 * EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,

 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;

 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,

 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR

 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF

 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 *

 * $Id$

 */

/*

    		 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.

*/

/**********************************************************************

$Author: release $

$Date: 1998/01/17 15:55:47 $

$Revision: 1.1.1.1 $

$Log: tags.h,v $

 * Revision 1.1.1.1  1998/01/17  15:55:47  release

 * First version to be checked into rolling release.

 *

 * Revision 1.9  1997/10/28  12:04:40  pwe

 * comment only

 *

 * Revision 1.8  1997/10/10  18:15:44  pwe

 * prep ANDF-DE revision

 *

 * Revision 1.7  1995/08/31  14:19:02  currie

 * mjg mods

 *

 * Revision 1.6  1995/08/15  08:25:35  currie

 * Shift left + trap_tag

 *

 * Revision 1.5  1995/08/09  10:33:09  currie

 * otagexp list reorganised

 *

 * Revision 1.4  1995/06/26  13:04:40  currie

 * make_stack_limit, env_size etc

 *

 * Revision 1.2  1995/05/05  08:10:58  currie

 * initial_value + signtures

 *

 * Revision 1.1  1995/04/06  10:44:05  currie

 * Initial revision

 *

***********************************************************************/

#ifndef c_diff

#define ident_tag 1

#define seq_tag 3

#define cond_tag 4

#define labst_tag 5

#define rep_tag 6

#define goto_tag 7

#define test_tag 8

#define ass_tag 9

#define apply_tag 11

#define res_tag 12

#define goto_lv_tag 13

#define return_to_label_tag 14

#define solve_tag 15

#define assvol_tag 16

#define compound_tag 17

#define nof_tag 18

#define local_free_all_tag 19

#define local_free_tag 20

#define last_local_tag 21

#define long_jump_tag 22

#define concatnof_tag 23

#define ncopies_tag 24

#define case_tag 25

#define movecont_tag 26

#define testbit_tag 27

#define alloca_tag 28

#ifndef NEWDIAGS

#define diagnose_tag 29

#endif

#define prof_tag 30

#define ignorable_tag 31

#define bfass_tag 32

#define bfassvol_tag 33

#define condassign_tag 34

#define apply_general_tag 35

#define tail_call_tag 36

#define untidy_return_tag 37

#define same_callees_tag 38

#define plus_tag 39

#define neg_tag 40

#define shl_tag 41

#define mod_tag 43

#define rem2_tag 44

#define abs_tag 45

#define round_tag 46

#define offset_pad_tag 47

#define offset_div_tag 48

#define offset_max_tag 49

#define minptr_tag 50

#define fpower_tag 51

#define fplus_tag 52

#define fminus_tag 53

#define fmult_tag 54

#define fdiv_tag 55

#define fabs_tag 56

#define fneg_tag 57

#define float_tag 58

#define chfl_tag 59

#define and_tag 60

#define or_tag 61

#define xor_tag 62

#define not_tag 63

#define component_tag 64

#define max_tag 65

#define min_tag 66

#define bitf_to_int_tag 67

#define bfcont_tag 68

#define fmax_tag 69

#define shr_tag 70

#define fmin_tag 71

#define div0_tag 72

#define bfcontvol_tag 73

#define absbool_tag 74

#define addptr_tag 75

#define chvar_tag 76

#define minus_tag 77

#define mult_tag 78

#define subptr_tag 79

#define realpart_tag 80

#define div1_tag 81

#define div2_tag 82

#define offset_add_tag 83

#define offset_div_by_int_tag 84

#define offset_mult_tag 85

#define offset_negate_tag 86

#define offset_subtract_tag 87

#define rem0_tag 88

#define rotl_tag 89

#define rotr_tag 90

#define power_tag 91

#define imag_tag 92

#define make_complex_tag 93

#define int_to_bitf_tag 94

#define conj_tag 95

#define hold_tag 101

#define hold2_tag 102 /* 102 also used as hold */

#define initial_value_tag 103 /* removed in common part */

#define cont_tag 113

#define field_tag 114

#define val_tag 115

#define reff_tag 116

#define name_tag 117

#define proc_tag 118

#define top_tag 119

#define contvol_tag 120

#define current_env_tag 121

#define env_offset_tag 122

#define make_lv_tag 123

#define clear_tag 124

#define null_tag 125

#define real_tag 126

#define string_tag 127

#define general_proc_tag 128

#define env_size_tag 129

#define give_stack_limit_tag 130

#define make_stack_limit_tag 131

#define general_env_offset_tag 132

#define caller_tag 200

#define caller_name_tag 201

#define make_dynamic_callee_tag 204

#define make_callee_list_tag 205

#define set_stack_limit_tag 206

#define formal_callee_tag 207

#define trap_tag 208

#define asm_tag 209

#define is_o(t)	((t) >= cont_tag && (t) <= make_stack_limit_tag)

#define is_a(t)	((t) >= plus_tag && (t) <= make_stack_limit_tag)

#endif /* c_diff */

/***********************************************************************

NOTE that an exp can occur in just one place in the tree, because of

the backward pointers. Except for name_tag the general structure is

that an exp has a son which is nilexp or its first argument exp. The

next argument is the bro of the first, the next the bro of that etc.

The last argument has the last field set and its bro is the head exp

of the construction. In a name_tag the son contains the ident_tag which

declares the identity or variable being used. case, env_offset and string

are also special cases.

The pt field is used in goto and test-like constructions to hold the

labst being jumped to. It is used in ident and name constructions

to hold a list of uses of a declaration.

A name_tag or an exp with at pt to a labst MUST NOT be removed from

the tree without the usage count being decreased. In the case of name_tag

the exp must be removed from the pt-list which starts in the pt

of the defining ident_tag. kill_exp does these operations. It

also applies kill_exp recursively to all arguments.

For constructions not involving tags or labels, install_fns.c contains

examples of ways of constructing exps which may be used during

TDF transformations. However, at the time when the functions in

install_fns.c are being used, tags and labels are represented by

indexes into arrays. During TDF transformations this is no longer so.

name_tag refers directly to the ident_tag of the appropriate declaration,

and labels are represented by labst_tag exps. The form of a labst is

explained below, but remember that the count of uses must be kept

correctly up to date. The form of ident_tag and name_tag constructions

are also explained below, as are the uses of some functions defined

in me_fns.c to help in creating them.

The props field is zero except for those properties defined in the

expmacs.h file. Operations with ntests, rounding modes or error treatments

have these represented in the props field. as in expmacs.h.

An exp should normally have hold_check applied to it after being created.

abs_tag: Represents integer abs construction.

	son(e) is arg1.

	shape is sh(arg1).

	pt(e) is labst if error_jump, nilexp otherwise.

absbool_tag: Represents comparison and conversion to boolean.

	     Only produced (by check.c) is has_setcc is 1.

	son(e) is arg1.

	bro(arg1) is arg2.

	shape is a variety shape.

	ntest is represented in props, qv.

	pt(e) is nilexp.

	no(e) is 0.

	Delivers 1 in shape if arg1 ntest arg2, 0 otherwise.

addptr_tag: Adds pointer and offset to produce pointer.

	son(e) is arg1 (pointer).

	bro(arg1) is arg2 (offset).

	shape is pointer(al2(sh(arg2))).

	pt(e) is nilexp.

	no(e) is 0.

alloca_tag: Represents local_alloc construction.

	son(e) is arg1.

	shape is pointer(x).

	no(e) is 0.

	props(e) is 0.

	pt(e) is nilexp.

and_tag: represents and

	son(e) is a brother list of argument, all of the same shape.

		At least two arguments. After check any constants will

		have been combined into one, which will be the last exp

		if there is a constant contribution.

	shape is shape of son(e). This may be changed in some installers

		by chvar_tag transformations in check - only if

		has_byte_ops is 1.

	no(e) is 0.

	pt(e) is nilexp.

apply_tag: Represents apply_proc construction.

	son(e) is arg1

	bro(son(e)) is arg2 in the form of a brother list of zero or

		more exps.

	shape is result_shape.

	no(e) is 0.

	pt(e) is nilexp.

	Properties in the props field are defined in expmacs.h

asm_tag: Represents the ~asm group of token applications

	son(e) is arg.

	shape is top.

	no(e) is 0.

	pt(e) is nilexp.

	Properties in the props field are defined in expmacs.h

ass_tag: Represents assign construction.

	son(e) is arg1.

	bro(son(e)) is arg2.

	shape is top.

	no(e) is 0.

	pt(e) is nilexp.

assvol_tag: Represents assign_to_volatile construction.

	son(e) is arg1.

	bro(son(e)) is arg2.

	shape is top.

	no(e) is 0.

	pt(e) is nilexp.

bfass_tag and bfassvol_tag: represent bitfield assignment ops.

bfcont_tag and bfcontvol_tag: represent bitfield contents ops.

	These tags are removed by check.c and should not be seen

	elsewhere.

bitf_to_int_tag: represents bitfield to int conversion.

	son(e)arg1.

	shape is variety being converted to.

	no(e) is 0.

	pt(e) is nilexp.

case_tag: Represents case construction.

	son(e) is control.

	bro(son(e)) is a brother list of exps representing branches.

		Each element is zero-named exp with:

			pt is destination labst_tag.

			no is lower limit.

			if upper limit is equal to lower

			  then son is nilexp

			  else son is exp with no the upper limit.

		The elements of this list are arranged in increasing

		order of lower limit.

	shape is bottom if exhausive, top otherwise.

	no(e) is 0.

	pt(e) is nilexp.

chfl_tag: represents change floating variety

	son(e) is arg1.

	shape is floating shape being converted to.

	no(e) is 0;

	pt(e) is nilexp.

chvar_tag: represents change variety

	son(e) is arg1.

	shape is variety being converted to.

	no(e) is 0.

	pt(e) is nilexp.

clear_tag: represents make_value

	son(e) is nilexp.

	shape is shape of value required.

	no(e) is 0.

	pt(e) is nilexp.

component_tag: represents component

	Always removed by check.c. Should not occur elsewhere.

compound_tag: Represents the compound construction.

	son(e) is arg2 in the form of a brother list of zero

		or more pairs. The first of each pair will be a val_tag

		with shape some offset. Its no field will be the offset

		in which to put the next item of the pair.

	shape is compound(arg1).

	pt(e) is nilexp.

	no(e) is 0.

concatnof_tag: represents concat nof

	son(e) is arg1.

	bro(arg1) is arg2

		arg1 and arg2 will be nof(m, s) and nof(n, s)

	shape is nof(m + n, s)

	no(e) is 0.

	pt(e) is nilexp.

cond_tag: Represents conditional construction.

	son(e) is first.

	bro(son(e)) is alt, which will be a labst_tag

	shape is LUB of first and alt.

	pt(e) is nilexp.

	no(e) is 0.

cont_tag: represents contents

contvol_tag: represents contents with volatile qualifier.

	son(e) is arg1 (a pointer).

	shape is shape of value being extracted.

	no(e) is 0.

	pt(e) is nilexp.

	Properties in the props field are defined in expmacs.h

current_env_tag: represents current env

	son(e) is nilexp

	shape is pointer(frame alignment).

	no(e) is 0.

	pt(e) is nilexp.

diagnose_tag: represents a diagnosing operation.

	dno(e) is diag_info (qv.).

	son(e) is controlled exp.

	shape is sh(son(e))

	pt(e) is nilexp.

div0_tag:

div1_tag:

div2_tag: represent div0/1/2

	son(e) is arg1.

	bro(arg1) is arg2.

	shape is sh(arg1) unless changed by chvar_tag (has_byte_ops).

	no(e) is 0.

	pt(e) is labst if error_jump, nilexp otherwise.

	Remember to increment labst count if used.

env_offset_tag: represents env_offset

	son(e) is ident_tag referred to.

	shape is offset from frame alignment.

	no(e) is 0.

	pt(e) is nilexp.

fabs_tag: represents floating abs

	son(e) is arg1.

	shape is sh(arg1).

	no(e) is 0.

	pt(e) is labst if error_jump, nilexp otherwise.

	Remember to increment labst count if used.

fdiv_tag: represents floating division.

	son(e) is arg1.

	bro(arg1) is arg2.

	shape is sh(arg1).

	no(e) is 0.

	pt(e) is labst if error_jump, nilexp otherwise.

	Remember to increment labst count if used.

field_tag: represents selection from a compound shape.

	son(e) is arg1 (value of shape compound).

	shape is shape of the component required.

	no(e) is the offset (in bits) from the start of the

		compound to the required component.

	pt(e) is nilexp.

float_tag: represents conversion from int to float.

	son(e) is arg1 (int).

	shape is the floating shape required.

	no(e) is 0.

	pt(e) is labst if error_jump, nilexp otherwise.

	Remember to increment labst count if used.

fmax_tag:

fmin_tag: represents floating maximum and minimum

	son(e) is arg1.

	bro(arg1) is arg2.

	shape is sh(arg1.

	no(e) is 0.

	pt(e) is nilexp.

fminus_tag: represents floating subtraction.

	son(e) is arg1.

	bro(arg1) is arg2.

	shape is sh(arg1).

	no(e) is 0.

	pt(e) is labst if error_jump, nilexp otherwise.

	Remember to increment labst count if used.

fmult_tag: represents floating multiplication

	son(e) is a brother list of argument, all of the same shape.

		At least two arguments. After check any constants will

		have been combined into one, which will be the last exp

		if there is a constant contribution.

	shape is shape of son(e).

	no(e) is 0.

	pt(e) is labst if error_jump, nilexp otherwise.

	Remember to increment labst count if used.

fneg_tag: represents floating negation.

	son(e) is arg1.

	shape is sh(arg1).

	no(e) is 0.

	pt(e) is labst if error_jump, nilexp otherwise.

	Remember to increment labst count if used.

fplus_tag: represents floating addition.

	son(e) is a brother list of argument, all of the same shape.

		At least two arguments. After check any constants will

		have been combined into one, which will be the last exp

		if there is a constant contribution.

	shape is shape of son(e).

	no(e) is 0.

	pt(e) is labst if error_jump, nilexp otherwise.

	Remember to increment labst count if used.

fpower_tag: represents floating power

	son(e) is arg1.

	bro(arg1) is arg2.

	shape is shape of son(e).

	no(e) is 0.

	pt(e) is labst if error_jump, nilexp otherwise.

	Remember to increment labst count if used.

goto_tag: Represents goto construction.

	son(e) is nilexp.

	shape is bottom.

	pt(e) is destination labst_tag.

	Create using me_l1, then set the pt field and increment

	the usage counter in the labst_tag.

goto_lv_tag: Represents the goto_local_lv construction.

	son(e) is local_lv value.

	shape is bottom.

	pt(e) is nilexp.

	no(e) is 0.

hold_tag: used as a dummy father at some times.

	son(e) is exp being so held.

ident_tag: Represents identify and variable constructions.

	For identify: son(e) is definition, bro(son(e)) is body.

	For variable: son(e) is init, bro(son(e)) is body.

	The shape of the result is the shape of body.

        The no(e) is a count of the number of uses.

        The pt(e) is the start of a chain of uses through name_tag's.

	Properties in the props field are defined in expmacs.h

	Create an ident_tag using me_startid, add name_tag uses of it

	using me_obtain, complete the definition using me_complete_id.

ignorable_tag: represents ignorable construction.

	son(e) is exp being controlled.

	shape is sh(son(e)).

	no(e) is 0.

	pt(e) is nilexp.

imag_tag: represents imaginary part.

	son(e) is complex number.

	shape is floating shape with same control parameters as the

	 complex.

	no(e) is 0.

	pt(e) is nilexp.

int_to_bitf_tag: represents integer to bitfield conversion.

	son(e) is arg1 (int).

	shape is bitfield required.

	no(e) is 0.

	pt(e) is nilexp.

labst_tag: Represents exps which are destination of jumps. Produced from

	alt of conditional, body of repeat and each place of labelled.

	son(e) is a holder.

	bro(son(e)) is the destination exp.

	shape is shape of bro(son(e)).

	pt(e) is nilexp.

	Properties in the props field are defined in expmacs.h

	The holder (i.e. the son of the labst) can have any name_tag;

	its no field is the number of uses of the labst and

	its bro is the destination exp. No other field is defined.

last_local_tag: represents last_local construction.

	son(e) is nilexp.

	shape is top.

	pt(e) is pointer(x).

	no(e) is 0.

local_free_all_tag: represents local_free_all construction.

	son(e) is nilexp.

	shape is top.

	pt(e) is nilexp.

	no(e) is 0.

local_free_tag: Represents local_free construction.

	son(e) is arg2 (pointer).

	bro(son(e)) is arg1 (offset).

	shape is top.

	pt(e) is nilexp.

	no(e) is 0.

long_jump_tag: Represents long_jump construction.

	son(e) is arg1.

	bro(son(e)) is arg2.

	shape is bottom.

	pt(e) is nilexp.

	no(e) is 0.

make_complex_tag: represent make complex number.

	son(e) is arg1.

	bro(arg1) is arg2.

	no(e) is 0.

	pt(e) is nilexp.

make_lv_tag: represents make label value.

	son(e) is nilexp.

	shape is lv.

	pt(e) is labst.

	no(e) is 0.

	Remember to increment labst count.

max_tag:

min_tag: represent maximum and minimum integer ops.

	son(e) is arg1.

	bro(arg1) is arg2.

	no(e) is 0.

	pt(e) is nilexp.

minptr_tag: Represents subtract_pointers construction.

	son(e) is arg1

	bro(son(e)) is arg2

	shape is offset(al1(arg2),al1(arg1))

	pt(e) is nilexp.

	no(e) is 0.

minus_tag: represents subtraction.

	This is replaced by addition of negation by check.c.

mod_tag: Represents rem1 construction.

	son(e) is arg1.

	bro(son(e)) is arg2

	shape is sh(arg1)

	pt(e) is labst if error_jump, nilexp otherwise.

	no(e) is 0.

movecont_tag: Represents move_some construction.

	son(e) is arg1.

	bro(son(e)) is arg2.

	bro(bro(son(e))) is arg3.

	shape is top.

	pt(e) is nilexp.

	no(e) is 0.

	Properties in the props field are defined in expmacs.h

mult_tag: represents integer multiplication.

	son(e) is a brother list of argument, all of the same shape.

		At least two arguments. After check any constants will

		have been combined into one, which will be the last exp

		if there is a constant contribution.

	shape is shape of son(e).

	no(e) is 0.

	pt(e) is labst if error_jump, nilexp otherwise.

	Remember to increment labst count if used.

name_tag: Represents obtain_tag

	son(e) is declaration (an ident_tag).

	no(e) is offset in bits from the start of that declaration's

		value.

	pt(e) is the next name_tag on the chain of uses of an ident_tag,

		which started in th pt field of the ident_tag, or

		nilexp if the end of the chain.

	Properties in the props field are defined in expmacs.h

	Remember to increment ident_tag count or use me_obtain from

	me_fns.c to create this.

ncopies_tag: represents ncopies.

	son(e) is value to be copied.

	no(e) is n, the number of copies.

	shape is nof(n, sh(son(e))).

	pt(e) is nilexp.

neg_tag: Represents negate construction

	son(e) is arg1.

	shape is sh(arg1).

	no(e) is 0.

	pt(e) is destination labst if ov_err is error_jump, otherwise

		nilexp.

nof_tag: represents the make_nof construction.

	son(e) is arg1 as a brother list of zero or more exps, each of

		the same shape (under eq_shape).

	shape is nof(n, shape of item)

	pt(e) is nilexp.

	no(e) is 0.

not_tag: Represents logical complement construction

	son(e) is arg1.

	shape is sh(arg1).

	no(e) is 0.

	pt(e) is nilexp.

null_tag: represent ptr null and proc null.

	son(e) is nilexp.

	shape is pointer(approprite alignment).

	no(e) is 0.

	pt(e) is nilexp.

offset_add_tag: Represents offset_add construction.

	son(e) is arg1

	bro(son(e)) is arg2.

	shape is offset(max(al1(arg1),al1(arg2)),al2(arg2))

	pt(e) is nilexp.

	no(e) is 0.

offset_div_tag: Represents offset_div construction.

	son(e) is arg1

	bro(son(e)) is arg2.

	shape is integer(v).

	pt(e) is nilexp.

	no(e) is 0.

offset_div_by_int_tag: Represents offset_div_by_int construction.

	son(e) is arg1

	bro(son(e)) is arg2.

	shape is offset(x,x)

	pt(e) is nilexp.

	no(e) is 0.

offset_max_tag: Represents offset_max construction.

	son(e) is arg1

	bro(son(e)) is arg2.

	shape is offset(max(al1(arg1),al1(arg2)),max(al2(arg1),al2(arg2)))

	pt(e) is nilexp.

	no(e) is 0.

offset_mult_tag: Represents offset_mult construction.

	son(e) is arg1

	bro(son(e)) is arg2.

	shape is offset(x,x)

	pt(e) is nilexp.

	no(e) is 0.

offset_negate_tag: Represents offset_negate construction.

	son(e) is arg1

	shape is offset(x,x)

	pt(e) is nilexp.

	no(e) is 0.

offset_pad_tag: represents offset pad.

	son(e) is arg1 (offset).

	shape is offset of required padded shape.

	no(e) is 0.

	pt(e) is nilexp.

offset_subtract_tag: Represents offset_subtract construction.

	son(e) is arg1

	bro(son(e)) is arg2.

	shape is offset(al2(arg1),al2(arg2))

	pt(e) is nilexp.

	no(e) is 0.

or_tag: represents or

	son(e) is a brother list of argument, all of the same shape.

		At least two arguments. After check any constants will

		have been combined into one, which will be the last exp

		if there is a constant contribution.

	shape is shape of son(e).

	no(e) is 0.

	pt(e) is nilexp.

plus_tag: represents the combination of plus and minus constructions.

	son(e) is a brother list of argument, all of the same shape.

		At least two arguments. After check any constants will

		have been combined into one, which will be the last exp

		if there is a constant contribution.

	shape is shape of son(e).

	no(e) is 0.

	pt(e) is destination labst if ov_err is error_jump, otherwise

		nilexp.