2002-01-27 Daniel Jacobowitz <drow@mvista.com>

[deliverable/binutils-gdb.git] / opcodes / cgen-dis.c

diff --git a/opcodes/cgen-dis.c b/opcodes/cgen-dis.c
index 78b1cd90ed918f65212a72c075dd54bdb0396638..4622c8c47c32e3ab994a680d65c98ef1d2a7a488 100644 (file)
--- a/opcodes/cgen-dis.c
+++ b/opcodes/cgen-dis.c
@@ -1,6 +1,7 @@
 /* CGEN generic disassembler support code.
 
-   Copyright (C) 1996, 1997, 1998, 1999 Free Software Foundation, Inc.
+   Copyright 1996, 1997, 1998, 1999, 2000, 2001
+   Free Software Foundation, Inc.
 
    This file is part of the GNU Binutils and GDB, the GNU debugger.
 
@@ -26,6 +27,61 @@
 #include "symcat.h"
 #include "opcode/cgen.h"
 
+static CGEN_INSN_LIST *  hash_insn_array      PARAMS ((CGEN_CPU_DESC, const CGEN_INSN *, int, int, CGEN_INSN_LIST **, CGEN_INSN_LIST *));
+static CGEN_INSN_LIST *  hash_insn_list       PARAMS ((CGEN_CPU_DESC, const CGEN_INSN_LIST *, CGEN_INSN_LIST **, CGEN_INSN_LIST *));
+static void              build_dis_hash_table PARAMS ((CGEN_CPU_DESC));
+
+/* Return the number of decodable bits in this insn.  */
+static int
+count_decodable_bits (insn)
+  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 (hentbuf, insn, htable, hash)
+     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.
@@ -43,7 +99,7 @@ hash_insn_array (cd, insns, count, entsize, htable, hentbuf)
      CGEN_CPU_DESC cd;
      const CGEN_INSN * insns;
      int count;
-     int entsize;
+     int entsize ATTRIBUTE_UNUSED;
      CGEN_INSN_LIST ** htable;
      CGEN_INSN_LIST * hentbuf;
 {
@@ -64,31 +120,12 @@ hash_insn_array (cd, insns, count, entsize, htable, hentbuf)
         to hash on, so set both up.  */
 
       value = CGEN_INSN_BASE_VALUE (insn);
-      switch (CGEN_INSN_MASK_BITSIZE (insn))
-       {
-       case 8:
-         buf[0] = value;
-         break;
-       case 16:
-         if (big_p)
-           bfd_putb16 ((bfd_vma) value, buf);
-         else
-           bfd_putl16 ((bfd_vma) value, buf);
-         break;
-       case 32:
-         if (big_p)
-           bfd_putb32 ((bfd_vma) value, buf);
-         else
-           bfd_putl32 ((bfd_vma) value, buf);
-         break;
-       default:
-         abort ();
-       }
-
+      bfd_put_bits ((bfd_vma) value,
+                   buf,
+                   CGEN_INSN_MASK_BITSIZE (insn),
+                   big_p);
       hash = (* cd->dis_hash) (buf, value);
-      hentbuf->next = htable[hash];
-      hentbuf->insn = insn;
-      htable[hash] = hentbuf;
+      add_insn_to_hash_chain (hentbuf, insn, htable, hash);
     }
 
   return hentbuf;
@@ -121,31 +158,12 @@ hash_insn_list (cd, insns, htable, hentbuf)
         to hash on, so set both up.  */
 
       value = CGEN_INSN_BASE_VALUE (ilist->insn);
-      switch (CGEN_INSN_MASK_BITSIZE (ilist->insn))
-       {
-       case 8:
-         buf[0] = value;
-         break;
-       case 16:
-         if (big_p)
-           bfd_putb16 ((bfd_vma) value, buf);
-         else
-           bfd_putl16 ((bfd_vma) value, buf);
-         break;
-       case 32:
-         if (big_p)
-           bfd_putb32 ((bfd_vma) value, buf);
-         else
-           bfd_putl32 ((bfd_vma) value, buf);
-         break;
-       default:
-         abort ();
-       }
-
+      bfd_put_bits((bfd_vma) value,
+                  buf,
+                  CGEN_INSN_MASK_BITSIZE (ilist->insn),
+                  big_p);
       hash = (* cd->dis_hash) (buf, value);
-      hentbuf->next = htable [hash];
-      hentbuf->insn = ilist->insn;
-      htable [hash] = hentbuf;
+      add_insn_to_hash_chain (hentbuf, ilist->insn, htable, hash);
     }
 
   return hentbuf;