Initial revision

1 files changed, 618 insertions, 0 deletions

diff --git a/gas/subsegs.c b/gas/subsegs.c
new file mode 100644
index 0000000000..bdf28688bd
--- /dev/null
+++ b/gas/subsegs.c
@@ -0,0 +1,618 @@
+/* subsegs.c - subsegments -
+   Copyright (C) 1987, 90, 91, 92, 93, 94, 95, 96, 1997
+   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)
+   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, 59 Temple Place - Suite 330, Boston, MA
+   02111-1307, USA.  */
+
+/*
+ * Segments & sub-segments.
+ */
+
+#include "as.h"
+
+#include "subsegs.h"
+#include "obstack.h"
+
+frchainS *frchain_root, *frchain_now;
+
+static struct obstack frchains;
+
+#ifndef BFD_ASSEMBLER
+#ifdef MANY_SEGMENTS
+segment_info_type segment_info[SEG_MAXIMUM_ORDINAL];
+
+#else
+/* Commented in "subsegs.h". */
+frchainS *data0_frchainP, *bss0_frchainP;
+
+#endif /* MANY_SEGMENTS */
+char const *const seg_name[] =
+{
+  "absolute",
+#ifdef MANY_SEGMENTS
+  "e0", "e1", "e2", "e3", "e4", "e5", "e6", "e7", "e8", "e9",
+  "e10", "e11", "e12", "e13", "e14", "e15", "e16", "e17", "e18", "e19",
+  "e20", "e21", "e22", "e23", "e24", "e25", "e26", "e27", "e28", "e29",
+  "e30", "e31", "e32", "e33", "e34", "e35", "e36", "e37", "e38", "e39",
+#else
+  "text",
+  "data",
+  "bss",
+#endif /* MANY_SEGMENTS */
+  "unknown",
+  "ASSEMBLER-INTERNAL-LOGIC-ERROR!",
+  "expr",
+  "debug",
+  "transfert vector preload",
+  "transfert vector postload",
+  "register",
+  "",
+};				/* Used by error reporters, dumpers etc. */
+#else /* BFD_ASSEMBLER */
+
+/* Gas segment information for bfd_abs_section_ptr and
+   bfd_und_section_ptr.  */
+static segment_info_type *abs_seg_info;
+static segment_info_type *und_seg_info;
+
+#endif /* BFD_ASSEMBLER */
+
+static void subseg_set_rest PARAMS ((segT, subsegT));
+
+static fragS dummy_frag;
+
+static frchainS absolute_frchain;
+
+void
+subsegs_begin ()
+{
+  /* Check table(s) seg_name[], seg_N_TYPE[] is in correct order */
+#if !defined (MANY_SEGMENTS) && !defined (BFD_ASSEMBLER)
+  know (SEG_ABSOLUTE == 0);
+  know (SEG_TEXT == 1);
+  know (SEG_DATA == 2);
+  know (SEG_BSS == 3);
+  know (SEG_UNKNOWN == 4);
+  know (SEG_GOOF == 5);
+  know (SEG_EXPR == 6);
+  know (SEG_DEBUG == 7);
+  know (SEG_NTV == 8);
+  know (SEG_PTV == 9);
+  know (SEG_REGISTER == 10);
+  know (SEG_MAXIMUM_ORDINAL == SEG_REGISTER);
+#endif
+
+  obstack_begin (&frchains, chunksize);
+#if __GNUC__ >= 2
+  obstack_alignment_mask (&frchains) = __alignof__ (frchainS) - 1;
+#endif
+
+  frchain_root = NULL;
+  frchain_now = NULL;		/* Warn new_subseg() that we are booting. */
+
+  frag_now = &dummy_frag;
+
+#ifndef BFD_ASSEMBLER
+  now_subseg = 42;		/* Lie for 1st call to subseg_new. */
+#ifdef MANY_SEGMENTS
+  {
+    int i;
+    for (i = SEG_E0; i < SEG_UNKNOWN; i++)
+      {
+	subseg_set (i, 0);
+	segment_info[i].frchainP = frchain_now;
+      }
+  }
+#else
+  subseg_set (SEG_DATA, 0);	/* .data 0 */
+  data0_frchainP = frchain_now;
+
+  subseg_set (SEG_BSS, 0);
+  bss0_frchainP = frchain_now;
+
+#endif /* ! MANY_SEGMENTS */
+#endif /* ! BFD_ASSEMBLER */
+
+  absolute_frchain.frch_seg = absolute_section;
+  absolute_frchain.frch_subseg = 0;
+#ifdef BFD_ASSEMBLER
+  absolute_frchain.fix_root = absolute_frchain.fix_tail = 0;
+#endif
+  absolute_frchain.frch_frag_now = &zero_address_frag;
+  absolute_frchain.frch_root = absolute_frchain.frch_last = &zero_address_frag;
+}
+
+/*
+ *			subseg_change()
+ *
+ * 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_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;
+{
+  now_seg = seg;
+  now_subseg = subseg;
+
+  if (now_seg == absolute_section)
+    return;
+
+#ifdef BFD_ASSEMBLER
+  {
+    segment_info_type *seginfo;
+    seginfo = (segment_info_type *) bfd_get_section_userdata (stdoutput, seg);
+    if (! seginfo)
+      {
+	seginfo = (segment_info_type *) xmalloc (sizeof (*seginfo));
+	memset ((PTR) seginfo, 0, sizeof (*seginfo));
+	seginfo->fix_root = NULL;
+	seginfo->fix_tail = NULL;
+	seginfo->bfd_section = seg;
+	seginfo->sym = 0;
+	if (seg == bfd_abs_section_ptr)
+	  abs_seg_info = seginfo;
+	else if (seg == bfd_und_section_ptr)
+	  und_seg_info = seginfo;
+	else
+	  bfd_set_section_userdata (stdoutput, seg, (PTR) seginfo);
+      }
+  }
+#else
+#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 if (seg == SEG_TEXT)
+    {
+      seg_fix_rootP = &text_fix_root;
+      seg_fix_tailP = &text_fix_tail;
+    }
+  else
+    {
+      know (seg == SEG_BSS);
+      seg_fix_rootP = &bss_fix_root;
+      seg_fix_tailP = &bss_fix_tail;
+    }
+
+#endif
+#endif
+}
+
+static void
+subseg_set_rest (seg, subseg)
+     segT seg;
+     subsegT subseg;
+{
+  register frchainS *frcP;	/* crawl frchain chain */
+  register frchainS **lastPP;	/* address of last pointer */
+  frchainS *newP;		/* address of new frchain */
+
+  mri_common_symbol = NULL;
+
+  if (frag_now && frchain_now)
+    frchain_now->frch_frag_now = frag_now;
+
+  assert (frchain_now == 0
+	  || now_seg == undefined_section
+	  || now_seg == absolute_section
+	  || frchain_now->frch_last == frag_now);
+
+  subseg_change (seg, (int) subseg);
+
+  if (seg == absolute_section)
+    {
+      frchain_now = &absolute_frchain;
+      frag_now = &zero_address_frag;
+      return;
+    }
+
+  assert (frchain_now == 0
+	  || now_seg == undefined_section
+	  || frchain_now->frch_last == frag_now);
+
+  /*
+   * 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 && frcP->frch_seg <= seg;
+       frcP = *(lastPP = &frcP->frch_next))
+    {
+      if (frcP->frch_seg == 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
+      || (frcP->frch_seg > 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 (&frchains, sizeof (frchainS));
+      newP->frch_subseg = subseg;
+      newP->frch_seg = seg;
+#ifdef BFD_ASSEMBLER
+      newP->fix_root = NULL;
+      newP->fix_tail = NULL;
+#endif
+      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_root = newP->frch_last = newP->frch_frag_now;
+
+      *lastPP = newP;
+      newP->frch_next = frcP;	/* perhaps NULL */
+
+#ifdef BFD_ASSEMBLER
+      {
+	segment_info_type *seginfo;
+	seginfo = seg_info (seg);
+	if (seginfo && seginfo->frchainP == frcP)
+	  seginfo->frchainP = newP;
+      }
+#endif
+      
+      frcP = newP;
+    }
+  /*
+   * Here with frcP pointing to the frchainS for subseg.
+   */
+  frchain_now = frcP;
+  frag_now = frcP->frch_frag_now;
+
+  assert (frchain_now->frch_last == frag_now);
+}
+
+/*
+ *			subseg_set(segT, subsegT)
+ *
+ * If you attempt to change to the current subsegment, nothing happens.
+ *
+ * In:	segT, subsegT code for new subsegment.
+ *	frag_now -> incomplete frag for current subsegment.
+ *	If frag_now==NULL, then there is no old, incomplete frag, so
+ *	the old frag is not closed off.
+ *
+ * Out:	now_subseg, now_seg updated.
+ *	Frchain_now points to the (possibly new) struct frchain for this
+ *	sub-segment.
+ *	Frchain_root updated if needed.
+ */
+
+#ifndef BFD_ASSEMBLER
+
+segT
+subseg_new (segname, subseg)
+     const char *segname;
+     subsegT subseg;
+{
+  int i;
+
+  for (i = 0; i < (int) SEG_MAXIMUM_ORDINAL; i++)
+    {
+      const char *s;
+
+      s = segment_name ((segT) i);
+      if (strcmp (segname, s) == 0
+	  || (segname[0] == '.'
+	      && strcmp (segname + 1, s) == 0))
+	{
+	  subseg_set ((segT) i, subseg);
+	  return (segT) i;
+	}
+#ifdef obj_segment_name
+      s = obj_segment_name ((segT) i);
+      if (strcmp (segname, s) == 0
+	  || (segname[0] == '.'
+	      && strcmp (segname + 1, s) == 0))
+	{
+	  subseg_set ((segT) i, subseg);
+	  return (segT) i;
+	}
+#endif
+    }
+
+#ifdef obj_add_segment
+  {
+    segT new_seg;
+    new_seg = obj_add_segment (segname);
+    subseg_set (new_seg, subseg);
+    return new_seg;
+  }
+#else
+  as_bad (_("Attempt to switch to nonexistent segment \"%s\""), segname);
+  return now_seg;
+#endif
+}
+
+void
+subseg_set (seg, subseg)	/* begin assembly for a new sub-segment */
+     register segT seg;		/* SEG_DATA or SEG_TEXT */
+     register subsegT subseg;
+{
+#ifndef MANY_SEGMENTS
+  know (seg == SEG_DATA
+	|| seg == SEG_TEXT
+	|| seg == SEG_BSS
+	|| seg == SEG_ABSOLUTE);
+#endif
+
+  if (seg != now_seg || subseg != now_subseg)
+    {				/* we just changed sub-segments */
+      subseg_set_rest (seg, subseg);
+    }
+  mri_common_symbol = NULL;
+}
+
+#else /* BFD_ASSEMBLER */
+
+segT
+subseg_get (segname, force_new)
+     const char *segname;
+     int force_new;
+{
+  segT secptr;
+  segment_info_type *seginfo;
+  const char *now_seg_name = (now_seg
+			      ? bfd_get_section_name (stdoutput, 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)
+    {
+      /* Check whether output_section is set first because secptr may
+         be bfd_abs_section_ptr.  */
+      if (secptr->output_section != secptr)
+	secptr->output_section = secptr;
+      seginfo = (segment_info_type *) xmalloc (sizeof (*seginfo));
+      memset ((PTR) seginfo, 0, sizeof (*seginfo));
+      seginfo->fix_root = NULL;
+      seginfo->fix_tail = NULL;
+      seginfo->bfd_section = secptr;
+      if (secptr == bfd_abs_section_ptr)
+	abs_seg_info = seginfo;
+      else if (secptr == bfd_und_section_ptr)
+	und_seg_info = seginfo;
+      else
+	bfd_set_section_userdata (stdoutput, secptr, (PTR) seginfo);
+      seginfo->frchainP = NULL;
+      seginfo->lineno_list_head = seginfo->lineno_list_tail = NULL;
+      seginfo->sym = NULL;
+      seginfo->dot = NULL;
+    }
+  return secptr;
+}
+
+segT
+subseg_new (segname, subseg)
+     const char *segname;
+     subsegT subseg;
+{
+  segT secptr;
+  segment_info_type *seginfo;
+
+  secptr = subseg_get (segname, 0);
+  subseg_set_rest (secptr, subseg);
+  seginfo = seg_info (secptr);
+  if (! seginfo->frchainP)
+    seginfo->frchainP = frchain_now;
+  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 (segname, subseg)
+     const char *segname;
+     subsegT subseg;
+{
+  segT secptr;
+  segment_info_type *seginfo;
+
+  secptr = subseg_get (segname, 1);
+  subseg_set_rest (secptr, subseg);
+  seginfo = seg_info (secptr);
+  if (! seginfo->frchainP)
+    seginfo->frchainP = frchain_now;
+  return secptr;
+}
+
+void
+subseg_set (secptr, subseg)
+     segT secptr;
+     subsegT subseg;
+{
+  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
+
+/* Get the gas information we are storing for a section.  */
+
+segment_info_type *
+seg_info (sec)
+     segT sec;
+{
+  if (sec == bfd_abs_section_ptr)
+    return abs_seg_info;
+  else if (sec == bfd_und_section_ptr)
+    return und_seg_info;
+  else
+    return (segment_info_type *) bfd_get_section_userdata (stdoutput, sec);
+}
+
+symbolS *
+section_symbol (sec)
+     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
+#ifdef BFD_ASSEMBLER
+      || symbol_table_frozen
+#endif
+      )
+    {
+      /* Here we know it won't be going into the symbol table.  */
+      s = symbol_create (sec->name, sec, 0, &zero_address_frag);
+    }
+  else
+    {
+      s = symbol_find_base (sec->name, 0);
+      if (s == NULL)
+	s = symbol_new (sec->name, sec, 0, &zero_address_frag);
+      else
+	{
+	  if (S_GET_SEGMENT (s) == undefined_section)
+	    {
+	      S_SET_SEGMENT (s, sec);
+	      s->sy_frag = &zero_address_frag;
+	    }
+	}
+    }
+
+  S_CLEAR_EXTERNAL (s);
+
+  /* Use the BFD section symbol, if possible.  */
+  if (obj_sec_sym_ok_for_reloc (sec))
+    s->bsym = sec->symbol;
+
+  seginfo->sym = s;
+  return s;
+}
+
+#endif /* BFD_ASSEMBLER */
+
+void
+subsegs_print_statistics (file)
+     FILE *file;
+{
+  frchainS *frchp;
+  fprintf (file, "frag chains:\n");
+  for (frchp = frchain_root; frchp; frchp = frchp->frch_next)
+    {
+      int count = 0;
+      fragS *fragp;
+
+      /* If frch_subseg is non-zero, it's probably been chained onto
+	 the end of a previous subsection.  Don't count it again.  */
+      if (frchp->frch_subseg != 0)
+	continue;
+
+      /* Skip gas-internal sections.  */
+      if (segment_name (frchp->frch_seg)[0] == '*')
+	continue;
+
+      for (fragp = frchp->frch_root; fragp; fragp = fragp->fr_next)
+	{
+#if 0
+	  switch (fragp->fr_type)
+	    {
+	    case rs_fill:
+	      fprintf (file, "f"); break;
+	    case rs_align:
+	      fprintf (file, "a"); break;
+	    case rs_align_code:
+	      fprintf (file, "c"); break;
+	    case rs_org:
+	      fprintf (file, "o"); break;
+	    case rs_machine_dependent:
+	      fprintf (file, "m"); break;
+	    case rs_space:
+	      fprintf (file, "s"); break;
+	    case 0:
+	      fprintf (file, "0"); break;
+	    default:
+	      fprintf (file, "?"); break;
+	    }
+#endif
+	  count++;
+	}
+      fprintf (file, "\n");
+      fprintf (file, "\t%p %-10s\t%10d frags\n", frchp,
+	       segment_name (frchp->frch_seg), count);
+    }
+}
+
+/* end of subsegs.c */