/* subsegs.c - subsegments -
- Copyright (C) 1987, 1990, 1991 Free Software Foundation, Inc.
-
+ Copyright (C) 1987-2020 Free Software Foundation, Inc.
+
This file is part of GAS, the GNU Assembler.
-
+
GAS 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)
+ the Free Software Foundation; either version 3, or (at your option)
any later version.
-
+
GAS 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 GAS; see the file COPYING. If not, write to
- the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
+ along with GAS; see the file COPYING. If not, write to the Free
+ Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
+ 02110-1301, USA. */
-/*
- * Segments & sub-segments.
- */
+/* Segments & sub-segments. */
#include "as.h"
#include "subsegs.h"
#include "obstack.h"
-#ifdef MANY_SEGMENTS
-segment_info_type segment_info[SEG_MAXIMUM_ORDINAL];
+frchainS *frchain_now;
-frchainS* frchain_root,
- * frchain_now;
+static struct obstack frchains;
-#else
-frchainS* frchain_root,
- * frchain_now, /* Commented in "subsegs.h". */
- * data0_frchainP;
-
-#endif
-char * const /* in: segT out: char* */
- seg_name[] = {
- "absolute",
-#ifdef MANY_SEGMENTS
- "e0","e1","e2","e3","e4","e5","e6","e7","e8","e9",
-#else
- "text",
- "data",
- "bss",
-#endif
- "unknown",
- "absent",
- "pass1",
- "ASSEMBLER-INTERNAL-LOGIC-ERROR!",
- "bignum/flonum",
- "difference",
- "debug",
- "transfert vector preload",
- "transfert vector postload",
- "register",
- "",
- }; /* Used by error reporters, dumpers etc. */
+static fragS dummy_frag;
\f
void
- subsegs_begin()
+subsegs_begin (void)
{
- /* Check table(s) seg_name[], seg_N_TYPE[] is in correct order */
-#ifdef MANY_SEGMENTS
-#else
- know( SEG_ABSOLUTE == 0 );
- know( SEG_TEXT == 1 );
- know( SEG_DATA == 2 );
- know( SEG_BSS == 3 );
- know( SEG_UNKNOWN == 4 );
- know( SEG_ABSENT == 5 );
- know( SEG_PASS1 == 6 );
- know( SEG_GOOF == 7 );
- know( SEG_BIG == 8 );
- know( SEG_DIFFERENCE == 9 );
- know( SEG_DEBUG == 10 );
- know( SEG_NTV == 11 );
- know( SEG_PTV == 12 );
- know( SEG_REGISTER == 13 );
- know( SEG_MAXIMUM_ORDINAL == SEG_REGISTER );
- /* know( segment_name (SEG_MAXIMUM_ORDINAL + 1) [0] == 0 );*/
+ obstack_begin (&frchains, chunksize);
+#if __GNUC__ >= 2
+ obstack_alignment_mask (&frchains) = __alignof__ (frchainS) - 1;
#endif
-
- obstack_begin( &frags, 5000);
- frchain_root = NULL;
- frchain_now = NULL; /* Warn new_subseg() that we are booting. */
- /* Fake up 1st frag. */
- /* It won't be used=> is ok if obstack... */
- /* pads the end of it for alignment. */
- frag_now=(fragS *)obstack_alloc(&frags,SIZEOF_STRUCT_FRAG);
- memset(frag_now, SIZEOF_STRUCT_FRAG, 0);
- /* This 1st frag will not be in any frchain. */
- /* We simply give subseg_new somewhere to scribble. */
- now_subseg = 42; /* Lie for 1st call to subseg_new. */
-#ifdef MANY_SEGMENTS
- {
- int i;
- for (i = SEG_E0; i < SEG_UNKNOWN; i++) {
- subseg_new(i, 0);
- segment_info[i].frchainP = frchain_now;
- }
- }
-#else
- subseg_new (SEG_DATA, 0); /* .data 0 */
- data0_frchainP = frchain_now;
-#endif
-
+
+ frchain_now = NULL; /* Warn new_subseg() that we are booting. */
+ frag_now = &dummy_frag;
}
\f
/*
*
* Change the subsegment we are in, BUT DO NOT MAKE A NEW FRAG for the
* subsegment. If we are already in the correct subsegment, change nothing.
- * This is used eg as a worker for subseg_new [which does make a new frag_now]
+ * This is used eg as a worker for subseg_set [which does make a new frag_now]
* and for changing segments after we have read the source. We construct eg
* fixSs even after the source file is read, so we do have to keep the
* segment context correct.
*/
void
- subseg_change (seg, subseg)
-register segT seg;
-register int subseg;
+subseg_change (segT seg, int subseg)
{
- now_seg = seg;
- now_subseg = subseg;
-#ifdef MANY_SEGMENTS
- seg_fix_rootP = & segment_info[seg].fix_root;
- seg_fix_tailP = & segment_info[seg].fix_tail;
-#else
- if (seg == SEG_DATA)
- {
- seg_fix_rootP = & data_fix_root;
- seg_fix_tailP = & data_fix_tail;
- }
- else
- {
- know (seg == SEG_TEXT);
- seg_fix_rootP = & text_fix_root;
- seg_fix_tailP = & text_fix_tail;
- }
-#endif
+ segment_info_type *seginfo = seg_info (seg);
+ now_seg = seg;
+ now_subseg = subseg;
+
+ if (! seginfo)
+ {
+ seginfo = XCNEW (segment_info_type);
+ seginfo->bfd_section = seg;
+ bfd_set_section_userdata (seg, seginfo);
+ }
}
\f
+static void
+subseg_set_rest (segT seg, subsegT subseg)
+{
+ frchainS *frcP; /* crawl frchain chain */
+ frchainS **lastPP; /* address of last pointer */
+ frchainS *newP; /* address of new frchain */
+ segment_info_type *seginfo;
+
+ mri_common_symbol = NULL;
+
+ if (frag_now && frchain_now)
+ frchain_now->frch_frag_now = frag_now;
+
+ gas_assert (frchain_now == 0
+ || frchain_now->frch_last == frag_now);
+
+ subseg_change (seg, (int) subseg);
+
+ seginfo = seg_info (seg);
+
+ /* Attempt to find or make a frchain for that subsection.
+ We keep the list sorted by subsection number. */
+ for (frcP = *(lastPP = &seginfo->frchainP);
+ frcP != NULL;
+ frcP = *(lastPP = &frcP->frch_next))
+ if (frcP->frch_subseg >= subseg)
+ break;
+
+ if (frcP == NULL || frcP->frch_subseg != subseg)
+ {
+ /* This should be the only code that creates a frchainS. */
+
+ newP = (frchainS *) obstack_alloc (&frchains, sizeof (frchainS));
+ newP->frch_subseg = subseg;
+ newP->fix_root = NULL;
+ newP->fix_tail = NULL;
+ obstack_begin (&newP->frch_obstack, chunksize);
+#if __GNUC__ >= 2
+ obstack_alignment_mask (&newP->frch_obstack) = __alignof__ (fragS) - 1;
+#endif
+ newP->frch_frag_now = frag_alloc (&newP->frch_obstack);
+ newP->frch_frag_now->fr_type = rs_fill;
+ newP->frch_cfi_data = NULL;
+
+ newP->frch_root = newP->frch_last = newP->frch_frag_now;
+
+ *lastPP = newP;
+ newP->frch_next = frcP;
+ frcP = newP;
+ }
+
+ frchain_now = frcP;
+ frag_now = frcP->frch_frag_now;
+
+ gas_assert (frchain_now->frch_last == frag_now);
+}
+
/*
- * subseg_new()
+ * subseg_set(segT, subsegT)
*
* If you attempt to change to the current subsegment, nothing happens.
*
* Out: now_subseg, now_seg updated.
* Frchain_now points to the (possibly new) struct frchain for this
* sub-segment.
- * Frchain_root updated if needed.
*/
+segT
+subseg_get (const char *segname, int force_new)
+{
+ segT secptr;
+ segment_info_type *seginfo;
+ const char *now_seg_name = now_seg ? bfd_section_name (now_seg) : 0;
+
+ if (!force_new
+ && now_seg_name
+ && (now_seg_name == segname
+ || !strcmp (now_seg_name, segname)))
+ return now_seg;
+
+ if (!force_new)
+ secptr = bfd_make_section_old_way (stdoutput, segname);
+ else
+ secptr = bfd_make_section_anyway (stdoutput, segname);
+
+ seginfo = seg_info (secptr);
+ if (! seginfo)
+ {
+ secptr->output_section = secptr;
+ seginfo = XCNEW (segment_info_type);
+ seginfo->bfd_section = secptr;
+ bfd_set_section_userdata (secptr, seginfo);
+ }
+ return secptr;
+}
+
+segT
+subseg_new (const char *segname, subsegT subseg)
+{
+ segT secptr;
+
+ secptr = subseg_get (segname, 0);
+ subseg_set_rest (secptr, subseg);
+ return secptr;
+}
+
+/* Like subseg_new, except a new section is always created, even if
+ a section with that name already exists. */
+segT
+subseg_force_new (const char *segname, subsegT subseg)
+{
+ segT secptr;
+
+ secptr = subseg_get (segname, 1);
+ subseg_set_rest (secptr, subseg);
+ return secptr;
+}
+
void
- subseg_new (seg, subseg) /* begin assembly for a new sub-segment */
-register segT seg; /* SEG_DATA or SEG_TEXT */
-register subsegT subseg;
+subseg_set (segT secptr, subsegT subseg)
{
- long tmp; /* JF for obstack alignment hacking */
-#ifndef MANY_SEGMENTS
- know( seg == SEG_DATA || seg == SEG_TEXT );
+ if (! (secptr == now_seg && subseg == now_subseg))
+ subseg_set_rest (secptr, subseg);
+ mri_common_symbol = NULL;
+}
+
+#ifndef obj_sec_sym_ok_for_reloc
+#define obj_sec_sym_ok_for_reloc(SEC) 0
#endif
- if (seg != now_seg || subseg != now_subseg)
- { /* we just changed sub-segments */
- register frchainS * frcP; /* crawl frchain chain */
- register frchainS** lastPP; /* address of last pointer */
- frchainS * newP; /* address of new frchain */
- register fragS * former_last_fragP;
- register fragS * new_fragP;
-
- if (frag_now) /* If not bootstrapping. */
- {
- frag_now -> fr_fix = obstack_next_free(& frags) - frag_now -> fr_literal;
- frag_wane(frag_now); /* Close off any frag in old subseg. */
- }
- /*
- * It would be nice to keep an obstack for each subsegment, if we swap
- * subsegments a lot. Hence we would have much fewer frag_wanes().
- */
- {
-
- obstack_finish( &frags);
- /*
- * If we don't do the above, the next object we put on obstack frags
- * will appear to start at the fr_literal of the current frag.
- * Also, above ensures that the next object will begin on a
- * address that is aligned correctly for the engine that runs
- * this program.
- */
- }
- subseg_change (seg, (int)subseg);
- /*
- * Attempt to find or make a frchain for that sub seg.
- * Crawl along chain of frchainSs, begins @ frchain_root.
- * If we need to make a frchainS, link it into correct
- * position of chain rooted in frchain_root.
- */
- for (frcP = * (lastPP = & frchain_root);
- frcP
- && (int)(frcP -> frch_seg) <= (int)seg;
- frcP = * ( lastPP = & frcP -> frch_next)
- )
- {
- if ( (int)(frcP -> frch_seg) == (int)seg
- && frcP -> frch_subseg >= subseg)
- {
- break;
- }
- }
- /*
- * frcP: Address of the 1st frchainS in correct segment with
- * frch_subseg >= subseg.
- * We want to either use this frchainS, or we want
- * to insert a new frchainS just before it.
- *
- * If frcP==NULL, then we are at the end of the chain
- * of frchainS-s. A NULL frcP means we fell off the end
- * of the chain looking for a
- * frch_subseg >= subseg, so we
- * must make a new frchainS.
- *
- * If we ever maintain a pointer to
- * the last frchainS in the chain, we change that pointer
- * ONLY when frcP==NULL.
- *
- * lastPP: Address of the pointer with value frcP;
- * Never NULL.
- * May point to frchain_root.
- *
- */
- if ( ! frcP
- || ( (int)(frcP -> frch_seg) > (int)seg
- || frcP->frch_subseg > subseg)) /* Kinky logic only works with 2 segments. */
- {
- /*
- * This should be the only code that creates a frchainS.
- */
- newP=(frchainS *)obstack_alloc(&frags,sizeof(frchainS));
- memset(newP, sizeof(frchainS), 0);
- /* This begines on a good boundary */
- /* because a obstack_done() preceeded it. */
- /* It implies an obstack_done(), so we */
- /* expect the next object allocated to */
- /* begin on a correct boundary. */
- *lastPP = newP;
- newP -> frch_next = frcP; /* perhaps NULL */
- (frcP = newP) -> frch_subseg = subseg;
- newP -> frch_seg = seg;
- newP -> frch_last = NULL;
- }
- /*
- * Here with frcP ->ing to the frchainS for subseg.
- */
- frchain_now = frcP;
- /*
- * Make a fresh frag for the subsegment.
- */
- /* We expect this to happen on a correct */
- /* boundary since it was proceeded by a */
- /* obstack_done(). */
- tmp=obstack_alignment_mask(&frags); /* JF disable alignment */
- obstack_alignment_mask(&frags)=0;
- frag_now=(fragS *)obstack_alloc(&frags,SIZEOF_STRUCT_FRAG);
- obstack_alignment_mask(&frags)=tmp;
- /* know( frags . obstack_c_next_free == frag_now -> fr_literal ); */
- /* But we want any more chars to come */
- /* immediately after the structure we just made. */
- new_fragP = frag_now;
- new_fragP -> fr_next = NULL;
- /*
- * Append new frag to current frchain.
- */
- former_last_fragP = frcP -> frch_last;
- if (former_last_fragP)
- {
- know( former_last_fragP -> fr_next == NULL );
- know( frchain_now -> frch_root );
- former_last_fragP -> fr_next = new_fragP;
- }
- else
- {
- frcP -> frch_root = new_fragP;
- }
- frcP -> frch_last = new_fragP;
- } /* if (changing subsegments) */
-} /* subseg_new() */
-/*
- * Local Variables:
- * comment-column: 0
- * fill-column: 131
- * End:
- */
+symbolS *
+section_symbol (segT sec)
+{
+ segment_info_type *seginfo = seg_info (sec);
+ symbolS *s;
+
+ if (seginfo == 0)
+ abort ();
+ if (seginfo->sym)
+ return seginfo->sym;
+
+#ifndef EMIT_SECTION_SYMBOLS
+#define EMIT_SECTION_SYMBOLS 1
+#endif
+
+ if (! EMIT_SECTION_SYMBOLS || symbol_table_frozen)
+ {
+ /* Here we know it won't be going into the symbol table. */
+ s = symbol_create (sec->symbol->name, sec, 0, &zero_address_frag);
+ }
+ else
+ {
+ segT seg;
+ s = symbol_find (sec->symbol->name);
+ /* We have to make sure it is the right symbol when we
+ have multiple sections with the same section name. */
+ if (s == NULL
+ || ((seg = S_GET_SEGMENT (s)) != sec
+ && seg != undefined_section))
+ s = symbol_new (sec->symbol->name, sec, 0, &zero_address_frag);
+ else if (seg == undefined_section)
+ {
+ S_SET_SEGMENT (s, sec);
+ symbol_set_frag (s, &zero_address_frag);
+ }
+ }
+
+ S_CLEAR_EXTERNAL (s);
+
+ /* Use the BFD section symbol, if possible. */
+ if (obj_sec_sym_ok_for_reloc (sec))
+ symbol_set_bfdsym (s, sec->symbol);
+ else
+ symbol_get_bfdsym (s)->flags |= BSF_SECTION_SYM;
+
+ seginfo->sym = s;
+ return s;
+}
+
+/* Return whether the specified segment is thought to hold text. */
+
+int
+subseg_text_p (segT sec)
+{
+ return (bfd_section_flags (sec) & SEC_CODE) != 0;
+}
+
+/* Return non zero if SEC has at least one byte of data. It is
+ possible that we'll return zero even on a non-empty section because
+ we don't know all the fragment types, and it is possible that an
+ fr_fix == 0 one still contributes data. Think of this as
+ seg_definitely_not_empty_p. */
+
+int
+seg_not_empty_p (segT sec ATTRIBUTE_UNUSED)
+{
+ segment_info_type *seginfo = seg_info (sec);
+ frchainS *chain;
+ fragS *frag;
+
+ if (!seginfo)
+ return 0;
+
+ for (chain = seginfo->frchainP; chain; chain = chain->frch_next)
+ {
+ for (frag = chain->frch_root; frag; frag = frag->fr_next)
+ if (frag->fr_fix)
+ return 1;
+ if (obstack_next_free (&chain->frch_obstack)
+ != chain->frch_last->fr_literal)
+ return 1;
+ }
+ return 0;
+}
+
+void
+subsegs_print_statistics (FILE *file)
+{
+ frchainS *frchp;
+ asection *s;
+
+ /* PR 20897 - check to see if the output bfd was actually created. */
+ if (stdoutput == NULL)
+ return;
+
+ fprintf (file, "frag chains:\n");
+ for (s = stdoutput->sections; s; s = s->next)
+ {
+ segment_info_type *seginfo;
+
+ /* Skip gas-internal sections. */
+ if (segment_name (s)[0] == '*')
+ continue;
+
+ seginfo = seg_info (s);
+ if (!seginfo)
+ continue;
+
+ for (frchp = seginfo->frchainP; frchp; frchp = frchp->frch_next)
+ {
+ int count = 0;
+ fragS *fragp;
+
+ for (fragp = frchp->frch_root; fragp; fragp = fragp->fr_next)
+ count++;
+
+ fprintf (file, "\n");
+ fprintf (file, "\t%p %-10s\t%10d frags\n", (void *) frchp,
+ segment_name (s), count);
+ }
+ }
+}
/* end of subsegs.c */
projects / deliverable / binutils-gdb.git / blobdiff