/* frags.c - manage frags -
- 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. */
#include "as.h"
#include "subsegs.h"
#include "obstack.h"
-struct obstack frags; /* All, and only, frags live here. */
-
-fragS zero_address_frag = {
- 0, /* fr_address */
- NULL, /* fr_next */
- 0, /* fr_fix */
- 0, /* fr_var */
- 0, /* fr_symbol */
- 0, /* fr_offset */
- NULL, /* fr_opcode */
- rs_fill, /* fr_type */
- 0, /* fr_subtype */
- 0, /* fr_pcrel_adjust */
- 0, /* fr_bsr */
- 0 /* fr_literal [0] */
- };
-
-fragS bss_address_frag = {
- 0, /* fr_address. Gets filled in to make up
- sy_value-s. */
- NULL, /* fr_next */
- 0, /* fr_fix */
- 0, /* fr_var */
- 0, /* fr_symbol */
- 0, /* fr_offset */
- NULL, /* fr_opcode */
- rs_fill, /* fr_type */
- 0, /* fr_subtype */
- 0, /* fr_pcrel_adjust */
- 0, /* fr_bsr */
- 0 /* fr_literal [0] */
- };
+extern fragS zero_address_frag;
+extern fragS predefined_address_frag;
+
+static int totalfrags;
+
+int
+get_frag_count (void)
+{
+ return totalfrags;
+}
+
+void
+clear_frag_count (void)
+{
+ totalfrags = 0;
+}
\f
-/*
- * frag_grow()
- *
- * Internal.
- * Try to augment current frag by nchars chars.
- * If there is no room, close of the current frag with a ".fill 0"
- * and begin a new frag. Unless the new frag has nchars chars available
- * do not return. Do not set up any fields of *now_frag.
- */
-static void frag_grow(nchars)
-unsigned int nchars;
+/* Initialization for frag routines. */
+
+void
+frag_init (void)
{
- if (obstack_room (&frags) < nchars) {
- unsigned int n,oldn;
- long oldc;
-
- frag_wane(frag_now);
- frag_new(0);
- oldn=(unsigned)-1;
- oldc=frags.chunk_size;
- frags.chunk_size=2*nchars;
- while((n=obstack_room(&frags))<nchars && n<oldn) {
- frag_wane(frag_now);
- frag_new(0);
- oldn=n;
- }
- frags.chunk_size=oldc;
- }
- if (obstack_room (&frags) < nchars)
- as_fatal("Can't extend frag %d. chars", nchars);
-} /* frag_grow() */
+ zero_address_frag.fr_type = rs_fill;
+ predefined_address_frag.fr_type = rs_fill;
+}
+\f
+/* Check that we're not trying to assemble into a section that can't
+ allocate frags (currently, this is only possible in the absolute
+ section), or into an mri common. */
+
+static void
+frag_alloc_check (const struct obstack *ob)
+{
+ if (ob->chunk_size == 0)
+ {
+ as_bad (_("attempt to allocate data in absolute section"));
+ subseg_set (text_section, 0);
+ }
+
+ if (mri_common_symbol != NULL)
+ {
+ as_bad (_("attempt to allocate data in common section"));
+ mri_common_symbol = NULL;
+ }
+}
+
+/* Allocate a frag on the specified obstack.
+ Call this routine from everywhere else, so that all the weird alignment
+ hackery can be done in just one place. */
+
+fragS *
+frag_alloc (struct obstack *ob)
+{
+ fragS *ptr;
+ int oalign;
+
+ (void) obstack_alloc (ob, 0);
+ oalign = obstack_alignment_mask (ob);
+ obstack_alignment_mask (ob) = 0;
+ ptr = (fragS *) obstack_alloc (ob, SIZEOF_STRUCT_FRAG);
+ obstack_alignment_mask (ob) = oalign;
+ memset (ptr, 0, SIZEOF_STRUCT_FRAG);
+ totalfrags++;
+ return ptr;
+}
\f
-/*
- * frag_new()
- *
- * Call this to close off a completed frag, and start up a new (empty)
- * frag, in the same subsegment as the old frag.
- * [frchain_now remains the same but frag_now is updated.]
- * Because this calculates the correct value of fr_fix by
- * looking at the obstack 'frags', it needs to know how many
- * characters at the end of the old frag belong to (the maximal)
- * fr_var: the rest must belong to fr_fix.
- * It doesn't actually set up the old frag's fr_var: you may have
- * set fr_var == 1, but allocated 10 chars to the end of the frag:
- * in this case you pass old_frags_var_max_size == 10.
- *
- * Make a new frag, initialising some components. Link new frag at end
- * of frchain_now.
- */
-void frag_new(old_frags_var_max_size)
-int old_frags_var_max_size; /* Number of chars (already allocated on
- obstack frags) */
-/* in variable_length part of frag. */
+/* Try to augment current frag by nchars chars.
+ If there is no room, close off the current frag with a ".fill 0"
+ and begin a new frag. Then loop until the new frag has at least
+ nchars chars available. Does not set up any fields in frag_now. */
+
+void
+frag_grow (size_t nchars)
{
- register fragS * former_last_fragP;
- /* char *throw_away_pointer; JF unused */
- register frchainS * frchP;
- long tmp; /* JF */
-
- frag_now->fr_fix = (char *) (obstack_next_free (&frags)) -
- (frag_now->fr_literal) - old_frags_var_max_size;
- /* Fix up old frag's fr_fix. */
-
- obstack_finish (&frags);
- /* This will align the obstack so the */
- /* next struct we allocate on it will */
- /* begin at a correct boundary. */
- frchP = frchain_now;
- know (frchP);
- former_last_fragP = frchP->frch_last;
- know (former_last_fragP);
- know (former_last_fragP == frag_now);
- obstack_blank (&frags, SIZEOF_STRUCT_FRAG);
- /* We expect this will begin at a correct */
- /* boundary for a struct. */
- tmp=obstack_alignment_mask(&frags);
- obstack_alignment_mask(&frags)=0; /* Turn off alignment */
- /* If we ever hit a machine
- where strings must be
- aligned, we Lose Big */
- frag_now=(fragS *)obstack_finish(&frags);
- obstack_alignment_mask(&frags)=tmp; /* Restore alignment */
-
- /* Just in case we don't get zero'd bytes */
- bzero(frag_now, SIZEOF_STRUCT_FRAG);
-
- /* obstack_unaligned_done (&frags, &frag_now); */
- /* know (frags.obstack_c_next_free == frag_now->fr_literal); */
- /* Generally, frag_now->points to an */
- /* address rounded up to next alignment. */
- /* However, characters will add to obstack */
- /* frags IMMEDIATELY after the struct frag, */
- /* even if they are not starting at an */
- /* alignment address. */
- former_last_fragP->fr_next = frag_now;
- frchP->frch_last = frag_now;
-
+ if (obstack_room (&frchain_now->frch_obstack) < nchars)
+ {
+ size_t oldc;
+ size_t newc;
+
+ /* Try to allocate a bit more than needed right now. But don't do
+ this if we would waste too much memory. Especially necessary
+ for extremely big (like 2GB initialized) frags. */
+ if (nchars < 0x10000)
+ newc = 2 * nchars;
+ else
+ newc = nchars + 0x10000;
+ newc += SIZEOF_STRUCT_FRAG;
+
+ /* Check for possible overflow. */
+ if (newc < nchars)
+ as_fatal (ngettext ("can't extend frag %lu char",
+ "can't extend frag %lu chars",
+ (unsigned long) nchars),
+ (unsigned long) nchars);
+
+ /* Force to allocate at least NEWC bytes, but not less than the
+ default. */
+ oldc = obstack_chunk_size (&frchain_now->frch_obstack);
+ if (newc > oldc)
+ obstack_chunk_size (&frchain_now->frch_obstack) = newc;
+
+ while (obstack_room (&frchain_now->frch_obstack) < nchars)
+ {
+ /* Not enough room in this frag. Close it and start a new one.
+ This must be done in a loop because the created frag may not
+ be big enough if the current obstack chunk is used. */
+ frag_wane (frag_now);
+ frag_new (0);
+ }
+
+ /* Restore the old chunk size. */
+ obstack_chunk_size (&frchain_now->frch_obstack) = oldc;
+ }
+}
+\f
+/* Call this to close off a completed frag, and start up a new (empty)
+ frag, in the same subsegment as the old frag.
+ [frchain_now remains the same but frag_now is updated.]
+ Because this calculates the correct value of fr_fix by
+ looking at the obstack 'frags', it needs to know how many
+ characters at the end of the old frag belong to the maximal
+ variable part; The rest must belong to fr_fix.
+ It doesn't actually set up the old frag's fr_var. You may have
+ set fr_var == 1, but allocated 10 chars to the end of the frag;
+ In this case you pass old_frags_var_max_size == 10.
+ In fact, you may use fr_var for something totally unrelated to the
+ size of the variable part of the frag; None of the generic frag
+ handling code makes use of fr_var.
+
+ Make a new frag, initialising some components. Link new frag at end
+ of frchain_now. */
+
+void
+frag_new (size_t old_frags_var_max_size
+ /* Number of chars (already allocated on obstack frags) in
+ variable_length part of frag. */)
+{
+ fragS *former_last_fragP;
+ frchainS *frchP;
+
+ gas_assert (frchain_now->frch_last == frag_now);
+
+ /* Fix up old frag's fr_fix. */
+ frag_now->fr_fix = frag_now_fix_octets ();
+ gas_assert (frag_now->fr_fix >= old_frags_var_max_size);
+ frag_now->fr_fix -= old_frags_var_max_size;
+ /* Make sure its type is valid. */
+ gas_assert (frag_now->fr_type != 0);
+
+ /* This will align the obstack so the next struct we allocate on it
+ will begin at a correct boundary. */
+ obstack_finish (&frchain_now->frch_obstack);
+ frchP = frchain_now;
+ know (frchP);
+ former_last_fragP = frchP->frch_last;
+ gas_assert (former_last_fragP != 0);
+ gas_assert (former_last_fragP == frag_now);
+ frag_now = frag_alloc (&frchP->frch_obstack);
+
+ frag_now->fr_file = as_where (&frag_now->fr_line);
+
+ /* Generally, frag_now->points to an address rounded up to next
+ alignment. However, characters will add to obstack frags
+ IMMEDIATELY after the struct frag, even if they are not starting
+ at an alignment address. */
+ former_last_fragP->fr_next = frag_now;
+ frchP->frch_last = frag_now;
+
#ifndef NO_LISTING
- {
- extern struct list_info_struct *listing_tail;
- frag_now->line = listing_tail;
- }
+ {
+ extern struct list_info_struct *listing_tail;
+ frag_now->line = listing_tail;
+ }
#endif
-
- frag_now->fr_next = NULL;
-} /* frag_new() */
+
+ gas_assert (frchain_now->frch_last == frag_now);
+
+ frag_now->fr_next = NULL;
+}
\f
-/*
- * frag_more()
- *
- * Start a new frag unless we have n more chars of room in the current frag.
- * Close off the old frag with a .fill 0.
- *
- * Return the address of the 1st char to write into. Advance
- * frag_now_growth past the new chars.
- */
-
-char *frag_more (nchars)
-int nchars;
+/* Start a new frag unless we have n more chars of room in the current frag.
+ Close off the old frag with a .fill 0.
+
+ Return the address of the 1st char to write into. Advance
+ frag_now_growth past the new chars. */
+
+char *
+frag_more (size_t nchars)
{
- register char *retval;
-
- frag_grow (nchars);
- retval = obstack_next_free (&frags);
- obstack_blank_fast (&frags, nchars);
- return (retval);
-} /* frag_more() */
+ char *retval;
+
+ frag_alloc_check (&frchain_now->frch_obstack);
+ frag_grow (nchars);
+ retval = obstack_next_free (&frchain_now->frch_obstack);
+ obstack_blank_fast (&frchain_now->frch_obstack, nchars);
+ return retval;
+}
\f
-/*
- * frag_var()
- *
- * Start a new frag unless we have max_chars more chars of room in the current frag.
- * Close off the old frag with a .fill 0.
- *
- * Set up a machine_dependent relaxable frag, then start a new frag.
- * Return the address of the 1st char of the var part of the old frag
- * to write into.
- */
-
-char *frag_var(type, max_chars, var, subtype, symbol, offset, opcode)
-relax_stateT type;
-int max_chars;
-int var;
-relax_substateT subtype;
-symbolS *symbol;
-long offset;
-char *opcode;
+/* Close the current frag, setting its fields for a relaxable frag. Start a
+ new frag. */
+
+static void
+frag_var_init (relax_stateT type, size_t max_chars, size_t var,
+ relax_substateT subtype, symbolS *symbol, offsetT offset,
+ char *opcode)
+{
+ frag_now->fr_var = var;
+ frag_now->fr_type = type;
+ frag_now->fr_subtype = subtype;
+ frag_now->fr_symbol = symbol;
+ frag_now->fr_offset = offset;
+ frag_now->fr_opcode = opcode;
+#ifdef USING_CGEN
+ frag_now->fr_cgen.insn = 0;
+ frag_now->fr_cgen.opindex = 0;
+ frag_now->fr_cgen.opinfo = 0;
+#endif
+#ifdef TC_FRAG_INIT
+ TC_FRAG_INIT (frag_now, max_chars);
+#endif
+ frag_now->fr_file = as_where (&frag_now->fr_line);
+
+ frag_new (max_chars);
+}
+
+/* Start a new frag unless we have max_chars more chars of room in the
+ current frag. Close off the old frag with a .fill 0.
+
+ Set up a machine_dependent relaxable frag, then start a new frag.
+ Return the address of the 1st char of the var part of the old frag
+ to write into. */
+
+char *
+frag_var (relax_stateT type, size_t max_chars, size_t var,
+ relax_substateT subtype, symbolS *symbol, offsetT offset,
+ char *opcode)
{
- register char *retval;
-
- frag_grow (max_chars);
- retval = obstack_next_free (&frags);
- obstack_blank_fast (&frags, max_chars);
- frag_now->fr_var = var;
- frag_now->fr_type = type;
- frag_now->fr_subtype = subtype;
- frag_now->fr_symbol = symbol;
- frag_now->fr_offset = offset;
- frag_now->fr_opcode = opcode;
- /* default these to zero. */
- frag_now->fr_pcrel_adjust = 0;
- frag_now->fr_bsr = 0;
- frag_new (max_chars);
- return (retval);
-} /* frag_var() */
+ char *retval;
+
+ frag_grow (max_chars);
+ retval = obstack_next_free (&frchain_now->frch_obstack);
+ obstack_blank_fast (&frchain_now->frch_obstack, max_chars);
+ frag_var_init (type, max_chars, var, subtype, symbol, offset, opcode);
+ return retval;
+}
\f
-/*
- * frag_variant()
- *
- * OVE: This variant of frag_var assumes that space for the tail has been
- * allocated by caller.
- * No call to frag_grow is done.
- * Two new arguments have been added.
- */
-
-char *frag_variant(type, max_chars, var, subtype, symbol, offset, opcode, pcrel_adjust,bsr)
-relax_stateT type;
-int max_chars;
-int var;
-relax_substateT subtype;
-symbolS *symbol;
-long offset;
-char *opcode;
-int pcrel_adjust;
-char bsr;
+/* OVE: This variant of frag_var assumes that space for the tail has been
+ allocated by caller.
+ No call to frag_grow is done. */
+
+char *
+frag_variant (relax_stateT type, size_t max_chars, size_t var,
+ relax_substateT subtype, symbolS *symbol, offsetT offset,
+ char *opcode)
{
- register char *retval;
-
- /* frag_grow (max_chars); */
- retval = obstack_next_free (&frags);
- /* obstack_blank_fast (&frags, max_chars); */ /* OVE: so far the only diff */
- frag_now->fr_var = var;
- frag_now->fr_type = type;
- frag_now->fr_subtype = subtype;
- frag_now->fr_symbol = symbol;
- frag_now->fr_offset = offset;
- frag_now->fr_opcode = opcode;
- frag_now->fr_pcrel_adjust = pcrel_adjust;
- frag_now->fr_bsr = bsr;
- frag_new (max_chars);
- return (retval);
-} /* frag_variant() */
+ char *retval;
+
+ retval = obstack_next_free (&frchain_now->frch_obstack);
+ frag_var_init (type, max_chars, var, subtype, symbol, offset, opcode);
+
+ return retval;
+}
\f
-/*
- * frag_wane()
- *
- * Reduce the variable end of a frag to a harmless state.
- */
-void frag_wane(fragP)
-register fragS * fragP;
+/* Reduce the variable end of a frag to a harmless state. */
+
+void
+frag_wane (fragS *fragP)
{
- fragP->fr_type = rs_fill;
- fragP->fr_offset = 0;
- fragP->fr_var = 0;
+ fragP->fr_type = rs_fill;
+ fragP->fr_offset = 0;
+ fragP->fr_var = 0;
}
\f
-/*
- * frag_align()
- *
- * Make a frag for ".align foo,bar". Call is "frag_align (foo,bar);".
- * Foo & bar are absolute integers.
- *
- * Call to close off the current frag with a ".align", then start a new
- * (so far empty) frag, in the same subsegment as the last frag.
- */
-
-void frag_align(alignment, fill_character)
-int alignment;
-int fill_character;
+/* Return the number of bytes by which the current frag can be grown. */
+
+size_t
+frag_room (void)
+{
+ return obstack_room (&frchain_now->frch_obstack);
+}
+\f
+/* Make an alignment frag. The size of this frag will be adjusted to
+ force the next frag to have the appropriate alignment. ALIGNMENT
+ is the power of two to which to align. FILL_CHARACTER is the
+ character to use to fill in any bytes which are skipped. MAX is
+ the maximum number of characters to skip when doing the alignment,
+ or 0 if there is no maximum. */
+
+void
+frag_align (int alignment, int fill_character, int max)
+{
+ if (now_seg == absolute_section)
+ {
+ addressT new_off;
+ addressT mask;
+
+ mask = (~(addressT) 0) << alignment;
+ new_off = (abs_section_offset + ~mask) & mask;
+ if (max == 0 || new_off - abs_section_offset <= (addressT) max)
+ abs_section_offset = new_off;
+ }
+ else
+ {
+ char *p;
+
+ p = frag_var (rs_align, 1, 1, (relax_substateT) max,
+ (symbolS *) 0, (offsetT) alignment, (char *) 0);
+ *p = fill_character;
+ }
+}
+
+/* Make an alignment frag like frag_align, but fill with a repeating
+ pattern rather than a single byte. ALIGNMENT is the power of two
+ to which to align. FILL_PATTERN is the fill pattern to repeat in
+ the bytes which are skipped. N_FILL is the number of bytes in
+ FILL_PATTERN. MAX is the maximum number of characters to skip when
+ doing the alignment, or 0 if there is no maximum. */
+
+void
+frag_align_pattern (int alignment, const char *fill_pattern,
+ size_t n_fill, int max)
+{
+ char *p;
+
+ p = frag_var (rs_align, n_fill, n_fill, (relax_substateT) max,
+ (symbolS *) 0, (offsetT) alignment, (char *) 0);
+ memcpy (p, fill_pattern, n_fill);
+}
+
+/* The NOP_OPCODE is for the alignment fill value. Fill it with a nop
+ instruction so that the disassembler does not choke on it. */
+#ifndef NOP_OPCODE
+#define NOP_OPCODE 0x00
+#endif
+
+/* Use this to restrict the amount of memory allocated for representing
+ the alignment code. Needs to be large enough to hold any fixed sized
+ prologue plus the replicating portion. */
+#ifndef MAX_MEM_FOR_RS_ALIGN_CODE
+ /* Assume that if HANDLE_ALIGN is not defined then no special action
+ is required to code fill, which means that we get just repeat the
+ one NOP_OPCODE byte. */
+# ifndef HANDLE_ALIGN
+# define MAX_MEM_FOR_RS_ALIGN_CODE 1
+# else
+# define MAX_MEM_FOR_RS_ALIGN_CODE ((1 << alignment) - 1)
+# endif
+#endif
+
+void
+frag_align_code (int alignment, int max)
+{
+ char *p;
+
+ p = frag_var (rs_align_code, MAX_MEM_FOR_RS_ALIGN_CODE, 1,
+ (relax_substateT) max, (symbolS *) 0,
+ (offsetT) alignment, (char *) 0);
+ *p = NOP_OPCODE;
+}
+
+addressT
+frag_now_fix_octets (void)
+{
+ if (now_seg == absolute_section)
+ return abs_section_offset;
+
+ return ((char *) obstack_next_free (&frchain_now->frch_obstack)
+ - frag_now->fr_literal);
+}
+
+addressT
+frag_now_fix (void)
{
- *(frag_var (rs_align, 1, 1, (relax_substateT)0, (symbolS *)0,
- (long)alignment, (char *)0)) = fill_character;
-} /* frag_align() */
+ /* Symbols whose section has SEC_ELF_OCTETS set,
+ resolve to octets instead of target bytes. */
+ if (now_seg->flags & SEC_OCTETS)
+ return frag_now_fix_octets ();
+ else
+ return frag_now_fix_octets () / OCTETS_PER_BYTE;
+}
-/* end: frags.c */
+void
+frag_append_1_char (int datum)
+{
+ frag_alloc_check (&frchain_now->frch_obstack);
+ if (obstack_room (&frchain_now->frch_obstack) <= 1)
+ {
+ frag_wane (frag_now);
+ frag_new (0);
+ }
+ obstack_1grow (&frchain_now->frch_obstack, datum);
+}
+
+/* Return TRUE if FRAG1 and FRAG2 have a fixed relationship between
+ their start addresses. Set OFFSET to the difference in address
+ not already accounted for in the frag FR_ADDRESS. */
+
+bfd_boolean
+frag_offset_fixed_p (const fragS *frag1, const fragS *frag2, offsetT *offset)
+{
+ const fragS *frag;
+ offsetT off;
+
+ /* Start with offset initialised to difference between the two frags.
+ Prior to assigning frag addresses this will be zero. */
+ off = frag1->fr_address - frag2->fr_address;
+ if (frag1 == frag2)
+ {
+ *offset = off;
+ return TRUE;
+ }
+
+ /* Maybe frag2 is after frag1. */
+ frag = frag1;
+ while (frag->fr_type == rs_fill)
+ {
+ off += frag->fr_fix + frag->fr_offset * frag->fr_var;
+ frag = frag->fr_next;
+ if (frag == NULL)
+ break;
+ if (frag == frag2)
+ {
+ *offset = off;
+ return TRUE;
+ }
+ }
+
+ /* Maybe frag1 is after frag2. */
+ off = frag1->fr_address - frag2->fr_address;
+ frag = frag2;
+ while (frag->fr_type == rs_fill)
+ {
+ off -= frag->fr_fix + frag->fr_offset * frag->fr_var;
+ frag = frag->fr_next;
+ if (frag == NULL)
+ break;
+ if (frag == frag1)
+ {
+ *offset = off;
+ return TRUE;
+ }
+ }
+
+ return FALSE;
+}
+
+/* Return TRUE if we can determine whether FRAG2 OFF2 appears after
+ (strict >, not >=) FRAG1 OFF1, assuming it is not before. Set
+ *OFFSET so that resolve_expression will resolve an O_gt operation
+ between them to false (0) if they are guaranteed to be at the same
+ location, or to true (-1) if they are guaranteed to be at different
+ locations. Return FALSE conservatively, e.g. if neither result can
+ be guaranteed (yet).
+
+ They are known to be in the same segment, and not the same frag
+ (this is a fallback for frag_offset_fixed_p, that always takes care
+ of this case), and it is expected (from the uses this is designed
+ to simplify, namely location view increments) that frag2 is
+ reachable from frag1 following the fr_next links, rather than the
+ other way round. */
+
+bfd_boolean
+frag_gtoffset_p (valueT off2, const fragS *frag2,
+ valueT off1, const fragS *frag1, offsetT *offset)
+{
+ /* Insanity check. */
+ if (frag2 == frag1 || off1 > frag1->fr_fix)
+ return FALSE;
+
+ /* If the first symbol offset is at the end of the first frag and
+ the second symbol offset at the beginning of the second frag then
+ it is possible they are at the same address. Go looking for a
+ non-zero fr_fix in any frag between these frags. If found then
+ we can say the O_gt result will be true. If no such frag is
+ found we assume that frag1 or any of the following frags might
+ have a variable tail and thus the answer is unknown. This isn't
+ strictly true; some frags don't have a variable tail, but it
+ doesn't seem worth optimizing for those cases. */
+ const fragS *frag = frag1;
+ offsetT delta = off2 - off1;
+ for (;;)
+ {
+ delta += frag->fr_fix;
+ frag = frag->fr_next;
+ if (frag == frag2)
+ {
+ if (delta == 0)
+ return FALSE;
+ break;
+ }
+ /* If we run off the end of the frag chain then we have a case
+ where frag2 is not after frag1, ie. an O_gt expression not
+ created for .loc view. */
+ if (frag == NULL)
+ return FALSE;
+ }
+
+ *offset = (off2 - off1 - delta) * OCTETS_PER_BYTE;
+ return TRUE;
+}
projects / deliverable / binutils-gdb.git / blobdiff