xref: /openbmc/linux/arch/powerpc/xmon/ppc-dis.c (revision 9cfc5c90)
1 /* ppc-dis.c -- Disassemble PowerPC instructions
2    Copyright 1994, 1995, 2000, 2001, 2002, 2003, 2004, 2005, 2006
3    Free Software Foundation, Inc.
4    Written by Ian Lance Taylor, Cygnus Support
5 
6 This file is part of GDB, GAS, and the GNU binutils.
7 
8 GDB, GAS, and the GNU binutils are free software; you can redistribute
9 them and/or modify them under the terms of the GNU General Public
10 License as published by the Free Software Foundation; either version
11 2, or (at your option) any later version.
12 
13 GDB, GAS, and the GNU binutils are distributed in the hope that they
14 will be useful, but WITHOUT ANY WARRANTY; without even the implied
15 warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
16 the GNU General Public License for more details.
17 
18 You should have received a copy of the GNU General Public License
19 along with this file; see the file COPYING.  If not, write to the Free
20 Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.  */
21 
22 #include <asm/cputable.h>
23 #include "nonstdio.h"
24 #include "ansidecl.h"
25 #include "ppc.h"
26 #include "dis-asm.h"
27 
28 /* Print a PowerPC or POWER instruction.  */
29 
30 int
31 print_insn_powerpc (unsigned long insn, unsigned long memaddr)
32 {
33   const struct powerpc_opcode *opcode;
34   const struct powerpc_opcode *opcode_end;
35   unsigned long op;
36   int dialect;
37 
38   dialect = PPC_OPCODE_PPC | PPC_OPCODE_CLASSIC | PPC_OPCODE_COMMON
39 	      | PPC_OPCODE_64 | PPC_OPCODE_POWER4 | PPC_OPCODE_ALTIVEC;
40 
41   if (cpu_has_feature(CPU_FTRS_POWER5))
42     dialect |= PPC_OPCODE_POWER5;
43 
44   if (cpu_has_feature(CPU_FTRS_CELL))
45     dialect |= PPC_OPCODE_CELL | PPC_OPCODE_ALTIVEC;
46 
47   if (cpu_has_feature(CPU_FTRS_POWER6))
48     dialect |= PPC_OPCODE_POWER5 | PPC_OPCODE_POWER6 | PPC_OPCODE_ALTIVEC;
49 
50   /* Get the major opcode of the instruction.  */
51   op = PPC_OP (insn);
52 
53   /* Find the first match in the opcode table.  We could speed this up
54      a bit by doing a binary search on the major opcode.  */
55   opcode_end = powerpc_opcodes + powerpc_num_opcodes;
56  again:
57   for (opcode = powerpc_opcodes; opcode < opcode_end; opcode++)
58     {
59       unsigned long table_op;
60       const unsigned char *opindex;
61       const struct powerpc_operand *operand;
62       int invalid;
63       int need_comma;
64       int need_paren;
65 
66       table_op = PPC_OP (opcode->opcode);
67       if (op < table_op)
68 	break;
69       if (op > table_op)
70 	continue;
71 
72       if ((insn & opcode->mask) != opcode->opcode
73 	  || (opcode->flags & dialect) == 0)
74 	continue;
75 
76       /* Make two passes over the operands.  First see if any of them
77 	 have extraction functions, and, if they do, make sure the
78 	 instruction is valid.  */
79       invalid = 0;
80       for (opindex = opcode->operands; *opindex != 0; opindex++)
81 	{
82 	  operand = powerpc_operands + *opindex;
83 	  if (operand->extract)
84 	    (*operand->extract) (insn, dialect, &invalid);
85 	}
86       if (invalid)
87 	continue;
88 
89       /* The instruction is valid.  */
90       printf("%s", opcode->name);
91       if (opcode->operands[0] != 0)
92 	printf("\t");
93 
94       /* Now extract and print the operands.  */
95       need_comma = 0;
96       need_paren = 0;
97       for (opindex = opcode->operands; *opindex != 0; opindex++)
98 	{
99 	  long value;
100 
101 	  operand = powerpc_operands + *opindex;
102 
103 	  /* Operands that are marked FAKE are simply ignored.  We
104 	     already made sure that the extract function considered
105 	     the instruction to be valid.  */
106 	  if ((operand->flags & PPC_OPERAND_FAKE) != 0)
107 	    continue;
108 
109 	  /* Extract the value from the instruction.  */
110 	  if (operand->extract)
111 	    value = (*operand->extract) (insn, dialect, &invalid);
112 	  else
113 	    {
114 	      value = (insn >> operand->shift) & ((1 << operand->bits) - 1);
115 	      if ((operand->flags & PPC_OPERAND_SIGNED) != 0
116 		  && (value & (1 << (operand->bits - 1))) != 0)
117 		value -= 1 << operand->bits;
118 	    }
119 
120 	  /* If the operand is optional, and the value is zero, don't
121 	     print anything.  */
122 	  if ((operand->flags & PPC_OPERAND_OPTIONAL) != 0
123 	      && (operand->flags & PPC_OPERAND_NEXT) == 0
124 	      && value == 0)
125 	    continue;
126 
127 	  if (need_comma)
128 	    {
129 	      printf(",");
130 	      need_comma = 0;
131 	    }
132 
133 	  /* Print the operand as directed by the flags.  */
134 	  if ((operand->flags & PPC_OPERAND_GPR) != 0
135 	      || ((operand->flags & PPC_OPERAND_GPR_0) != 0 && value != 0))
136 	    printf("r%ld", value);
137 	  else if ((operand->flags & PPC_OPERAND_FPR) != 0)
138 	    printf("f%ld", value);
139 	  else if ((operand->flags & PPC_OPERAND_VR) != 0)
140 	    printf("v%ld", value);
141 	  else if ((operand->flags & PPC_OPERAND_RELATIVE) != 0)
142 	    print_address (memaddr + value);
143 	  else if ((operand->flags & PPC_OPERAND_ABSOLUTE) != 0)
144 	    print_address (value & 0xffffffff);
145 	  else if ((operand->flags & PPC_OPERAND_CR) == 0
146 		   || (dialect & PPC_OPCODE_PPC) == 0)
147 	    printf("%ld", value);
148 	  else
149 	    {
150 	      if (operand->bits == 3)
151 		printf("cr%ld", value);
152 	      else
153 		{
154 		  static const char *cbnames[4] = { "lt", "gt", "eq", "so" };
155 		  int cr;
156 		  int cc;
157 
158 		  cr = value >> 2;
159 		  if (cr != 0)
160 		    printf("4*cr%d+", cr);
161 		  cc = value & 3;
162 		  printf("%s", cbnames[cc]);
163 		}
164 	    }
165 
166 	  if (need_paren)
167 	    {
168 	      printf(")");
169 	      need_paren = 0;
170 	    }
171 
172 	  if ((operand->flags & PPC_OPERAND_PARENS) == 0)
173 	    need_comma = 1;
174 	  else
175 	    {
176 	      printf("(");
177 	      need_paren = 1;
178 	    }
179 	}
180 
181       /* We have found and printed an instruction; return.  */
182       return 4;
183     }
184 
185   if ((dialect & PPC_OPCODE_ANY) != 0)
186     {
187       dialect = ~PPC_OPCODE_ANY;
188       goto again;
189     }
190 
191   /* We could not find a match.  */
192   printf(".long 0x%lx", insn);
193 
194   return 4;
195 }
196