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/* This module handles expression trees.
Copyright (C) 1991, 1993 Free Software Foundation, Inc.
Written by Steve Chamberlain of Cygnus Support (sac@cygnus.com).
This file is part of GLD, the Gnu Linker.
GLD 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.
GLD 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 GLD; see the file COPYING. If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
/*
This module is in charge of working out the contents of expressions.
It has to keep track of the relative/absness of a symbol etc. This is
done by keeping all values in a struct (an etree_value_type) which
contains a value, a section to which it is relative and a valid bit.
*/
#include "bfd.h"
#include "sysdep.h"
#include "bfdlink.h"
#include "ld.h"
#include "ldmain.h"
#include "ldmisc.h"
#include "ldexp.h"
#include "ldgram.h"
#include "ldlang.h"
static void exp_print_token PARAMS ((token_code_type code));
static void make_abs PARAMS ((etree_value_type *ptr));
static etree_value_type new_abs PARAMS ((bfd_vma value));
static void check PARAMS ((lang_output_section_statement_type *os,
const char *name, const char *op));
static etree_value_type new_rel
PARAMS ((bfd_vma value, lang_output_section_statement_type *section));
static etree_value_type new_rel_from_section
PARAMS ((bfd_vma value, lang_output_section_statement_type *section));
static etree_value_type fold_binary
PARAMS ((etree_type *tree,
lang_output_section_statement_type *current_section,
lang_phase_type allocation_done,
bfd_vma dot, bfd_vma *dotp));
static etree_value_type fold_name
PARAMS ((etree_type *tree,
lang_output_section_statement_type *current_section,
lang_phase_type allocation_done,
bfd_vma dot));
static etree_value_type exp_fold_tree_no_dot
PARAMS ((etree_type *tree,
lang_output_section_statement_type *current_section,
lang_phase_type allocation_done));
static void
exp_print_token (code)
token_code_type code;
{
static CONST struct
{
token_code_type code;
char *name;
} table[] =
{
{ INT, "int" },
{ REL, "relocateable" },
{ NAME,"NAME" },
{ PLUSEQ,"+=" },
{ MINUSEQ,"-=" },
{ MULTEQ,"*=" },
{ DIVEQ,"/=" },
{ LSHIFTEQ,"<<=" },
{ RSHIFTEQ,">>=" },
{ ANDEQ,"&=" },
{ OREQ,"|=" },
{ OROR,"||" },
{ ANDAND,"&&" },
{ EQ,"==" },
{ NE,"!=" },
{ LE,"<=" },
{ GE,">=" },
{ LSHIFT,"<<" },
{ RSHIFT,">>=" },
{ ALIGN_K,"ALIGN" },
{ BLOCK,"BLOCK" },
{ SECTIONS,"SECTIONS" },
{ SIZEOF_HEADERS,"SIZEOF_HEADERS" },
{ NEXT,"NEXT" },
{ SIZEOF,"SIZEOF" },
{ ADDR,"ADDR" },
{ MEMORY,"MEMORY" },
{ DEFINED,"DEFINED" },
{ TARGET_K,"TARGET" },
{ SEARCH_DIR,"SEARCH_DIR" },
{ MAP,"MAP" },
{ QUAD,"QUAD" },
{ LONG,"LONG" },
{ SHORT,"SHORT" },
{ BYTE,"BYTE" },
{ ENTRY,"ENTRY" },
{ 0,(char *)NULL }
};
unsigned int idx;
for (idx = 0; table[idx].name != (char*)NULL; idx++) {
if (table[idx].code == code) {
fprintf(config.map_file, "%s", table[idx].name);
return;
}
}
/* Not in table, just print it alone */
fprintf(config.map_file, "%c",code);
}
static void
make_abs (ptr)
etree_value_type *ptr;
{
asection *s = ptr->section->bfd_section;
ptr->value += s->vma;
ptr->section = abs_output_section;
}
static etree_value_type
new_abs (value)
bfd_vma value;
{
etree_value_type new;
new.valid = true;
new.section = abs_output_section;
new.value = value;
return new;
}
static void
check (os, name, op)
lang_output_section_statement_type *os;
CONST char *name;
CONST char *op;
{
if (os == (lang_output_section_statement_type *)NULL) {
einfo("%F%P: %s uses undefined section %s\n", op, name);
}
if (os->processed == false) {
einfo("%F%P: %s forward reference of section %s\n",op, name);
}
}
etree_type *
exp_intop (value)
bfd_vma value;
{
etree_type *new = (etree_type *)stat_alloc((bfd_size_type)(sizeof(new->value)));
new->type.node_code = INT;
new->value.value = value;
new->type.node_class = etree_value;
return new;
}
/* Build an expression representing an unnamed relocateable value. */
etree_type *
exp_relop (section, value)
asection *section;
bfd_vma value;
{
etree_type *new = (etree_type *) stat_alloc (sizeof (new->rel));
new->type.node_code = REL;
new->type.node_class = etree_rel;
new->rel.section = section;
new->rel.value = value;
return new;
}
static etree_value_type
new_rel (value, section)
bfd_vma value;
lang_output_section_statement_type *section;
{
etree_value_type new;
new.valid = true;
new.value = value;
new.section = section;
return new;
}
static etree_value_type
new_rel_from_section (value, section)
bfd_vma value;
lang_output_section_statement_type *section;
{
etree_value_type new;
new.valid = true;
new.value = value;
new.section = section;
new.value -= section->bfd_section->vma;
return new;
}
static etree_value_type
fold_binary (tree, current_section, allocation_done, dot, dotp)
etree_type *tree;
lang_output_section_statement_type *current_section;
lang_phase_type allocation_done;
bfd_vma dot;
bfd_vma *dotp;
{
etree_value_type result;
result = exp_fold_tree(tree->binary.lhs, current_section,
allocation_done, dot, dotp);
if (result.valid) {
etree_value_type other;
other = exp_fold_tree(tree->binary.rhs,
current_section,
allocation_done, dot,dotp) ;
if (other.valid) {
/* If values are from different sections, or this is an */
/* absolute expression, make both source args absolute */
if (result.section != other.section ||
current_section == abs_output_section)
{
make_abs(&result);
make_abs(&other);
}
switch (tree->type.node_code)
{
case '%':
/* Mod, both absolule*/
if (other.value == 0) {
einfo("%F%S %% by zero\n");
}
result.value = (int)result.value % (int)other.value;
break;
case '/':
if (other.value == 0) {
einfo("%F%S / by zero\n");
}
result.value = (int)result.value / (int) other.value;
break;
#define BOP(x,y) case x : result.value = result.value y other.value;break;
BOP('+',+);
BOP('*',*);
BOP('-',-);
BOP(LSHIFT,<<);
BOP(RSHIFT,>>);
BOP(EQ,==);
BOP(NE,!=);
BOP('<',<);
BOP('>',>);
BOP(LE,<=);
BOP(GE,>=);
BOP('&',&);
BOP('^',^);
BOP('|',|);
BOP(ANDAND,&&);
BOP(OROR,||);
default:
FAIL();
}
}
else {
result.valid = false;
}
}
return result;
}
etree_value_type
invalid ()
{
etree_value_type new;
new.valid = false;
return new;
}
static etree_value_type
fold_name (tree, current_section, allocation_done, dot)
etree_type *tree;
lang_output_section_statement_type *current_section;
lang_phase_type allocation_done;
bfd_vma dot;
{
etree_value_type result;
switch (tree->type.node_code)
{
case SIZEOF_HEADERS:
if (allocation_done != lang_first_phase_enum)
{
result = new_abs ((bfd_vma)
bfd_sizeof_headers (output_bfd,
link_info.relocateable));
}
else
{
result.valid = false;
}
break;
case DEFINED:
{
struct bfd_link_hash_entry *h;
h = bfd_link_hash_lookup (link_info.hash, tree->name.name,
false, false, true);
result.value = (h != (struct bfd_link_hash_entry *) NULL
&& (h->type == bfd_link_hash_defined
|| h->type == bfd_link_hash_common));
result.section = 0;
result.valid = true;
}
break;
case NAME:
result.valid = false;
if (tree->name.name[0] == '.' && tree->name.name[1] == 0)
{
if (allocation_done != lang_first_phase_enum)
result = new_rel_from_section(dot, current_section);
else
result = invalid();
}
else if (allocation_done == lang_final_phase_enum)
{
struct bfd_link_hash_entry *h;
h = bfd_link_hash_lookup (link_info.hash, tree->name.name,
false, false, true);
if (h != (struct bfd_link_hash_entry *) NULL
&& h->type == bfd_link_hash_defined)
{
lang_output_section_statement_type *os;
os = (lang_output_section_statement_lookup
(h->u.def.section->output_section->name));
/* FIXME: Is this correct if this section is being
linked with -R? */
result = new_rel ((h->u.def.value
+ h->u.def.section->output_offset),
os);
}
if (result.valid == false)
einfo("%F%S: undefined symbol `%s' referenced in expression\n",
tree->name.name);
}
break;
case ADDR:
if (allocation_done != lang_first_phase_enum) {
lang_output_section_statement_type *os =
lang_output_section_find(tree->name.name);
check(os,tree->name.name,"ADDR");
result = new_rel((bfd_vma)0, os);
}
else {
result = invalid();
}
break;
case SIZEOF:
if(allocation_done != lang_first_phase_enum) {
lang_output_section_statement_type *os =
lang_output_section_find(tree->name.name);
check(os,tree->name.name,"SIZEOF");
result = new_abs((bfd_vma)(os->bfd_section->_raw_size));
}
else {
result = invalid();
}
break;
default:
FAIL();
break;
}
return result;
}
etree_value_type
exp_fold_tree (tree, current_section, allocation_done, dot, dotp)
etree_type *tree;
lang_output_section_statement_type *current_section;
lang_phase_type allocation_done;
bfd_vma dot;
bfd_vma *dotp;
{
etree_value_type result;
if (tree == (etree_type *)NULL) {
result.valid = false;
}
else {
switch (tree->type.node_class)
{
case etree_value:
result = new_rel(tree->value.value, current_section);
break;
case etree_rel:
if (allocation_done != lang_final_phase_enum)
result.valid = false;
else
result = new_rel ((tree->rel.value
+ tree->rel.section->output_section->vma
+ tree->rel.section->output_offset),
current_section);
break;
case etree_unary:
result = exp_fold_tree(tree->unary.child,
current_section,
allocation_done, dot, dotp);
if (result.valid == true)
{
switch(tree->type.node_code)
{
case ALIGN_K:
if (allocation_done != lang_first_phase_enum) {
result = new_rel_from_section(ALIGN_N(dot,
result.value) ,
current_section);
}
else {
result.valid = false;
}
break;
case ABSOLUTE:
if (allocation_done != lang_first_phase_enum)
{
if (current_section
== (lang_output_section_statement_type*)NULL)
{
/* Outside a section, so it's all ok */
}
else {
/* Inside a section, subtract the base of the section,
so when it's added again (in an assignment), everything comes out fine
*/
result.section = abs_output_section;
result.value -= current_section->bfd_section->vma;
result.valid = true;
}
}
else
{
result.valid = false;
}
break;
case '~':
make_abs(&result);
result.value = ~result.value;
break;
case '!':
make_abs(&result);
result.value = !result.value;
break;
case '-':
make_abs(&result);
result.value = -result.value;
break;
case NEXT:
if (allocation_done ==lang_allocating_phase_enum) {
make_abs(&result);
result.value = ALIGN_N(dot, result.value);
}
else {
/* Return next place aligned to value */
result.valid = false;
}
break;
default:
FAIL();
}
}
break;
case etree_trinary:
result = exp_fold_tree(tree->trinary.cond,
current_section,
allocation_done, dot, dotp);
if (result.valid) {
result = exp_fold_tree(result.value ?
tree->trinary.lhs:tree->trinary.rhs,
current_section,
allocation_done, dot, dotp);
}
break;
case etree_binary:
result = fold_binary(tree, current_section, allocation_done,
dot, dotp);
break;
case etree_assign:
if (tree->assign.dst[0] == '.' && tree->assign.dst[1] == 0) {
/* Assignment to dot can only be done during allocation */
if (allocation_done == lang_allocating_phase_enum) {
result = exp_fold_tree(tree->assign.src,
current_section,
lang_allocating_phase_enum, dot, dotp);
if (result.valid == false) {
einfo("%F%S invalid assignment to location counter\n");
}
else {
if (current_section ==
(lang_output_section_statement_type *)NULL) {
einfo("%F%S assignment to location counter invalid outside of SECTION\n");
}
else {
bfd_vma nextdot =result.value +
current_section->bfd_section->vma;
if (nextdot < dot) {
einfo("%F%S cannot move location counter backwards (from %V to %V)\n", dot, nextdot);
}
else {
*dotp = nextdot;
}
}
}
}
}
else
{
result = exp_fold_tree (tree->assign.src,
current_section, allocation_done,
dot, dotp);
if (result.valid)
{
struct bfd_link_hash_entry *h;
h = bfd_link_hash_lookup (link_info.hash, tree->assign.dst,
true, false, false);
if (h == (struct bfd_link_hash_entry *) NULL)
einfo ("%P%F:%s: hash creation failed\n", tree->assign.dst);
/* FIXME: Should we worry if the symbol is already
defined? */
h->type = bfd_link_hash_defined;
h->u.def.value = result.value;
h->u.def.section = result.section->bfd_section;
}
}
break;
case etree_name:
result = fold_name(tree, current_section, allocation_done, dot);
break;
default:
einfo("%F%S need more of these %d\n",tree->type.node_class );
}
}
return result;
}
static etree_value_type
exp_fold_tree_no_dot (tree, current_section, allocation_done)
etree_type *tree;
lang_output_section_statement_type *current_section;
lang_phase_type allocation_done;
{
return exp_fold_tree(tree, current_section, allocation_done, (bfd_vma)
0, (bfd_vma *)NULL);
}
etree_type *
exp_binop (code, lhs, rhs)
int code;
etree_type *lhs;
etree_type *rhs;
{
etree_type value, *new;
etree_value_type r;
value.type.node_code = code;
value.binary.lhs = lhs;
value.binary.rhs = rhs;
value.type.node_class = etree_binary;
r = exp_fold_tree_no_dot(&value,
abs_output_section,
lang_first_phase_enum );
if (r.valid)
{
return exp_intop(r.value);
}
new = (etree_type *)stat_alloc((bfd_size_type)(sizeof(new->binary)));
memcpy((char *)new, (char *)&value, sizeof(new->binary));
return new;
}
etree_type *
exp_trinop (code, cond, lhs, rhs)
int code;
etree_type *cond;
etree_type *lhs;
etree_type *rhs;
{
etree_type value, *new;
etree_value_type r;
value.type.node_code = code;
value.trinary.lhs = lhs;
value.trinary.cond = cond;
value.trinary.rhs = rhs;
value.type.node_class = etree_trinary;
r= exp_fold_tree_no_dot(&value, (lang_output_section_statement_type
*)NULL,lang_first_phase_enum);
if (r.valid) {
return exp_intop(r.value);
}
new = (etree_type *)stat_alloc((bfd_size_type)(sizeof(new->trinary)));
memcpy((char *)new,(char *) &value, sizeof(new->trinary));
return new;
}
etree_type *
exp_unop (code, child)
int code;
etree_type *child;
{
etree_type value, *new;
etree_value_type r;
value.unary.type.node_code = code;
value.unary.child = child;
value.unary.type.node_class = etree_unary;
r = exp_fold_tree_no_dot(&value,abs_output_section,
lang_first_phase_enum);
if (r.valid) {
return exp_intop(r.value);
}
new = (etree_type *)stat_alloc((bfd_size_type)(sizeof(new->unary)));
memcpy((char *)new, (char *)&value, sizeof(new->unary));
return new;
}
etree_type *
exp_nameop (code, name)
int code;
CONST char *name;
{
etree_type value, *new;
etree_value_type r;
value.name.type.node_code = code;
value.name.name = name;
value.name.type.node_class = etree_name;
r = exp_fold_tree_no_dot(&value,
(lang_output_section_statement_type *)NULL,
lang_first_phase_enum);
if (r.valid) {
return exp_intop(r.value);
}
new = (etree_type *)stat_alloc((bfd_size_type)(sizeof(new->name)));
memcpy((char *)new, (char *)&value, sizeof(new->name));
return new;
}
etree_type *
exp_assop (code, dst, src)
int code;
CONST char *dst;
etree_type *src;
{
etree_type value, *new;
value.assign.type.node_code = code;
value.assign.src = src;
value.assign.dst = dst;
value.assign.type.node_class = etree_assign;
#if 0
if (exp_fold_tree_no_dot(&value, &result)) {
return exp_intop(result);
}
#endif
new = (etree_type*)stat_alloc((bfd_size_type)(sizeof(new->assign)));
memcpy((char *)new, (char *)&value, sizeof(new->assign));
return new;
}
void
exp_print_tree (tree)
etree_type *tree;
{
switch (tree->type.node_class) {
case etree_value:
print_address(tree->value.value);
return;
case etree_rel:
fprintf (config.map_file, "%s:%s+", tree->rel.section->owner->filename,
tree->rel.section->name);
print_address (tree->rel.value);
return;
case etree_assign:
#if 0
if (tree->assign.dst->sdefs != (asymbol *)NULL){
fprintf(config.map_file,"%s (%x) ",tree->assign.dst->name,
tree->assign.dst->sdefs->value);
}
else {
fprintf(config.map_file,"%s (UNDEFINED)",tree->assign.dst->name);
}
#endif
fprintf(config.map_file,"%s ",tree->assign.dst);
exp_print_token(tree->type.node_code);
exp_print_tree(tree->assign.src);
break;
case etree_binary:
fprintf(config.map_file,"(");
exp_print_tree(tree->binary.lhs);
exp_print_token(tree->type.node_code);
exp_print_tree(tree->binary.rhs);
fprintf(config.map_file,")");
break;
case etree_trinary:
exp_print_tree(tree->trinary.cond);
fprintf(config.map_file,"?");
exp_print_tree(tree->trinary.lhs);
fprintf(config.map_file,":");
exp_print_tree(tree->trinary.rhs);
break;
case etree_unary:
exp_print_token(tree->unary.type.node_code);
if (tree->unary.child)
{
fprintf(config.map_file,"(");
exp_print_tree(tree->unary.child);
fprintf(config.map_file,")");
}
break;
case etree_undef:
fprintf(config.map_file,"????????");
break;
case etree_name:
if (tree->type.node_code == NAME) {
fprintf(config.map_file,"%s", tree->name.name);
}
else {
exp_print_token(tree->type.node_code);
if (tree->name.name)
fprintf(config.map_file,"(%s)", tree->name.name);
}
break;
default:
FAIL();
break;
}
}
bfd_vma
exp_get_vma (tree, def, name, allocation_done)
etree_type *tree;
bfd_vma def;
char *name;
lang_phase_type allocation_done;
{
etree_value_type r;
if (tree != (etree_type *)NULL) {
r = exp_fold_tree_no_dot(tree,
abs_output_section,
allocation_done);
if (r.valid == false && name) {
einfo("%F%S nonconstant expression for %s\n",name);
}
return r.value;
}
else {
return def;
}
}
int
exp_get_value_int (tree,def,name, allocation_done)
etree_type *tree;
int def;
char *name;
lang_phase_type allocation_done;
{
return (int)exp_get_vma(tree,(bfd_vma)def,name, allocation_done);
}
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