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Diffstat (limited to 'contrib/binutils/opcodes/cgen-dis.c')
| -rw-r--r-- | contrib/binutils/opcodes/cgen-dis.c | 241 |
1 files changed, 241 insertions, 0 deletions
diff --git a/contrib/binutils/opcodes/cgen-dis.c b/contrib/binutils/opcodes/cgen-dis.c new file mode 100644 index 0000000..cf23ebc --- /dev/null +++ b/contrib/binutils/opcodes/cgen-dis.c @@ -0,0 +1,241 @@ +/* CGEN generic disassembler support code. + + Copyright 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003 + Free Software Foundation, Inc. + + This file is part of the GNU Binutils and GDB, the GNU debugger. + + This program 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. + + This program 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 this program; if not, write to the Free Software Foundation, Inc., + 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */ + +#include "sysdep.h" +#include <stdio.h> +#include "ansidecl.h" +#include "libiberty.h" +#include "bfd.h" +#include "symcat.h" +#include "opcode/cgen.h" + +static CGEN_INSN_LIST * hash_insn_array (CGEN_CPU_DESC, const CGEN_INSN *, int, int, CGEN_INSN_LIST **, CGEN_INSN_LIST *); +static CGEN_INSN_LIST * hash_insn_list (CGEN_CPU_DESC, const CGEN_INSN_LIST *, CGEN_INSN_LIST **, CGEN_INSN_LIST *); +static void build_dis_hash_table (CGEN_CPU_DESC); +static int count_decodable_bits (const CGEN_INSN *); +static void add_insn_to_hash_chain (CGEN_INSN_LIST *, + const CGEN_INSN *, + CGEN_INSN_LIST **, + unsigned int); + +/* Return the number of decodable bits in this insn. */ +static int +count_decodable_bits (const CGEN_INSN *insn) +{ + unsigned mask = CGEN_INSN_BASE_MASK (insn); + int bits = 0; + int m; + for (m = 1; m != 0; m <<= 1) + { + if (mask & m) + ++bits; + } + return bits; +} + +/* Add an instruction to the hash chain. */ +static void +add_insn_to_hash_chain (CGEN_INSN_LIST *hentbuf, + const CGEN_INSN *insn, + CGEN_INSN_LIST **htable, + unsigned int hash) +{ + CGEN_INSN_LIST *current_buf; + CGEN_INSN_LIST *previous_buf; + int insn_decodable_bits; + + /* Add insns sorted by the number of decodable bits, in decreasing order. + This ensures that any insn which is a special case of another will be + checked first. */ + insn_decodable_bits = count_decodable_bits (insn); + previous_buf = NULL; + for (current_buf = htable[hash]; current_buf != NULL; + current_buf = current_buf->next) + { + int current_decodable_bits = count_decodable_bits (current_buf->insn); + if (insn_decodable_bits >= current_decodable_bits) + break; + previous_buf = current_buf; + } + + /* Now insert the new insn. */ + hentbuf->insn = insn; + hentbuf->next = current_buf; + if (previous_buf == NULL) + htable[hash] = hentbuf; + else + previous_buf->next = hentbuf; +} + +/* Subroutine of build_dis_hash_table to add INSNS to the hash table. + + COUNT is the number of elements in INSNS. + ENTSIZE is sizeof (CGEN_IBASE) for the target. + ??? No longer used but leave in for now. + HTABLE points to the hash table. + HENTBUF is a pointer to sufficiently large buffer of hash entries. + The result is a pointer to the next entry to use. + + The table is scanned backwards as additions are made to the front of the + list and we want earlier ones to be prefered. */ + +static CGEN_INSN_LIST * +hash_insn_array (CGEN_CPU_DESC cd, + const CGEN_INSN * insns, + int count, + int entsize ATTRIBUTE_UNUSED, + CGEN_INSN_LIST ** htable, + CGEN_INSN_LIST * hentbuf) +{ + int big_p = CGEN_CPU_ENDIAN (cd) == CGEN_ENDIAN_BIG; + int i; + + for (i = count - 1; i >= 0; --i, ++hentbuf) + { + unsigned int hash; + char buf [4]; + unsigned long value; + const CGEN_INSN *insn = &insns[i]; + + if (! (* cd->dis_hash_p) (insn)) + continue; + + /* We don't know whether the target uses the buffer or the base insn + to hash on, so set both up. */ + + value = CGEN_INSN_BASE_VALUE (insn); + bfd_put_bits ((bfd_vma) value, + buf, + CGEN_INSN_MASK_BITSIZE (insn), + big_p); + hash = (* cd->dis_hash) (buf, value); + add_insn_to_hash_chain (hentbuf, insn, htable, hash); + } + + return hentbuf; +} + +/* Subroutine of build_dis_hash_table to add INSNS to the hash table. + This function is identical to hash_insn_array except the insns are + in a list. */ + +static CGEN_INSN_LIST * +hash_insn_list (CGEN_CPU_DESC cd, + const CGEN_INSN_LIST *insns, + CGEN_INSN_LIST **htable, + CGEN_INSN_LIST *hentbuf) +{ + int big_p = CGEN_CPU_ENDIAN (cd) == CGEN_ENDIAN_BIG; + const CGEN_INSN_LIST *ilist; + + for (ilist = insns; ilist != NULL; ilist = ilist->next, ++ hentbuf) + { + unsigned int hash; + char buf[4]; + unsigned long value; + + if (! (* cd->dis_hash_p) (ilist->insn)) + continue; + + /* We don't know whether the target uses the buffer or the base insn + to hash on, so set both up. */ + + value = CGEN_INSN_BASE_VALUE (ilist->insn); + bfd_put_bits((bfd_vma) value, + buf, + CGEN_INSN_MASK_BITSIZE (ilist->insn), + big_p); + hash = (* cd->dis_hash) (buf, value); + add_insn_to_hash_chain (hentbuf, ilist->insn, htable, hash); + } + + return hentbuf; +} + +/* Build the disassembler instruction hash table. */ + +static void +build_dis_hash_table (CGEN_CPU_DESC cd) +{ + int count = cgen_insn_count (cd) + cgen_macro_insn_count (cd); + CGEN_INSN_TABLE *insn_table = & cd->insn_table; + CGEN_INSN_TABLE *macro_insn_table = & cd->macro_insn_table; + unsigned int hash_size = cd->dis_hash_size; + CGEN_INSN_LIST *hash_entry_buf; + CGEN_INSN_LIST **dis_hash_table; + CGEN_INSN_LIST *dis_hash_table_entries; + + /* The space allocated for the hash table consists of two parts: + the hash table and the hash lists. */ + + dis_hash_table = (CGEN_INSN_LIST **) + xmalloc (hash_size * sizeof (CGEN_INSN_LIST *)); + memset (dis_hash_table, 0, hash_size * sizeof (CGEN_INSN_LIST *)); + dis_hash_table_entries = hash_entry_buf = (CGEN_INSN_LIST *) + xmalloc (count * sizeof (CGEN_INSN_LIST)); + + /* Add compiled in insns. + Don't include the first one as it is a reserved entry. */ + /* ??? It was the end of all hash chains, and also the special + "invalid insn" marker. May be able to do it differently now. */ + + hash_entry_buf = hash_insn_array (cd, + insn_table->init_entries + 1, + insn_table->num_init_entries - 1, + insn_table->entry_size, + dis_hash_table, hash_entry_buf); + + /* Add compiled in macro-insns. */ + + hash_entry_buf = hash_insn_array (cd, macro_insn_table->init_entries, + macro_insn_table->num_init_entries, + macro_insn_table->entry_size, + dis_hash_table, hash_entry_buf); + + /* Add runtime added insns. + Later added insns will be prefered over earlier ones. */ + + hash_entry_buf = hash_insn_list (cd, insn_table->new_entries, + dis_hash_table, hash_entry_buf); + + /* Add runtime added macro-insns. */ + + hash_insn_list (cd, macro_insn_table->new_entries, + dis_hash_table, hash_entry_buf); + + cd->dis_hash_table = dis_hash_table; + cd->dis_hash_table_entries = dis_hash_table_entries; +} + +/* Return the first entry in the hash list for INSN. */ + +CGEN_INSN_LIST * +cgen_dis_lookup_insn (CGEN_CPU_DESC cd, const char * buf, CGEN_INSN_INT value) +{ + unsigned int hash; + + if (cd->dis_hash_table == NULL) + build_dis_hash_table (cd); + + hash = (* cd->dis_hash) (buf, value); + + return cd->dis_hash_table[hash]; +} |
