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Diffstat (limited to 'gas/subsegs.h')
-rw-r--r-- | gas/subsegs.h | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/gas/subsegs.h b/gas/subsegs.h new file mode 100644 index 0000000..b8dbaf7 --- /dev/null +++ b/gas/subsegs.h @@ -0,0 +1,65 @@ +/* subsegs.h -> subsegs.c + Copyright (C) 1987 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 1, 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. */ + +/* + * For every sub-segment the user mentions in the ASsembler program, + * we make one struct frchain. Each sub-segment has exactly one struct frchain + * and vice versa. + * + * Struct frchain's are forward chained (in ascending order of sub-segment + * code number). The chain runs through frch_next of each subsegment. + * This makes it hard to find a subsegment's frags + * if programmer uses a lot of them. Most programs only use text0 and + * data0, so they don't suffer. At least this way: + * (1) There are no "arbitrary" restrictions on how many subsegments + * can be programmed; + * (2) Subsegments' frchain-s are (later) chained together in the order in + * which they are emitted for object file viz text then data. + * + * From each struct frchain dangles a chain of struct frags. The frags + * represent code fragments, for that sub-segment, forward chained. + */ + +struct frchain /* control building of a frag chain */ +{ /* FRCH = FRagment CHain control */ + struct frag * frch_root; /* 1st struct frag in chain, or NULL */ + struct frag * frch_last; /* last struct frag in chain, or NULL */ + struct frchain * frch_next; /* next in chain of struct frchain-s */ + segT frch_seg; /* SEG_TEXT or SEG_DATA. */ + subsegT frch_subseg; /* subsegment number of this chain */ +}; + +typedef struct frchain frchainS; + +extern frchainS * frchain_root; /* NULL means no frchains yet. */ + /* all subsegments' chains hang off here */ + +extern frchainS * frchain_now; + /* Frchain we are assembling into now */ + /* That is, the current segment's frag */ + /* chain, even if it contains no (complete) */ + /* frags. */ + +extern frchainS * data0_frchainP; + /* Sentinel for frchain crawling. */ + /* Points to the 1st data-segment frchain. */ + /* (Which is pointed to by the last text- */ + /* segment frchain.) */ + +/* end: subsegs.h */ |