| /* subsegs.c - subsegments - |
| Copyright 1987, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, |
| 1999, 2000 |
| 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); |
| 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); |
| |
| seginfo->sym = s; |
| return s; |
| } |
| |
| #endif /* BFD_ASSEMBLER */ |
| |
| /* Return whether the specified segment is thought to hold text. */ |
| |
| #ifndef BFD_ASSEMBLER |
| const char * const nontext_section_names[] = { |
| ".eh_frame", |
| ".gcc_except_table", |
| #ifdef OBJ_COFF |
| #ifndef COFF_LONG_SECTION_NAMES |
| ".eh_fram", |
| ".gcc_exc", |
| #endif |
| #endif |
| NULL |
| }; |
| #endif /* ! BFD_ASSEMBLER */ |
| |
| int |
| subseg_text_p (sec) |
| segT sec; |
| { |
| #ifdef BFD_ASSEMBLER |
| return (bfd_get_section_flags (stdoutput, sec) & SEC_CODE) != 0; |
| #else /* ! BFD_ASSEMBLER */ |
| const char * const *p; |
| |
| if (sec == data_section || sec == bss_section || sec == absolute_section) |
| return 0; |
| |
| for (p = nontext_section_names; *p != NULL; ++p) |
| { |
| if (strcmp (segment_name (sec), *p) == 0) |
| return 0; |
| |
| #ifdef obj_segment_name |
| if (strcmp (obj_segment_name (sec), *p) == 0) |
| return 0; |
| #endif |
| } |
| |
| return 1; |
| |
| #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", (void *) frchp, |
| segment_name (frchp->frch_seg), count); |
| } |
| } |
| |
| /* end of subsegs.c */ |