4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
25 * Copyright 2005 Sun Microsystems, Inc. All rights reserved.
26 * Use is subject to license terms.
29 /* Copyright (c) 1988 AT&T */
30 /* All Rights Reserved */
34 #pragma ident "@(#)instr_size.c 1.14 05/07/08 SMI"
37 #include <sys/types.h>
38 #include <sys/param.h>
41 #include <sys/cmn_err.h>
42 #include <sys/archsystm.h>
43 #include <sys/copyops.h>
44 #include <vm/seg_enum.h>
45 #include <sys/privregs.h>
47 typedef u_int model_t;
48 #define DATAMODEL_NATIVE 0
49 int dtrace_instr_size(uchar_t *);
52 #include <dis_tables.h>
55 * This subsystem (with the minor exception of the instr_size() function) is
56 * is called from DTrace probe context. This imposes several requirements on
59 * 1. External subsystems and functions may not be referenced. The one current
60 * exception is for cmn_err, but only to signal the detection of table
61 * errors. Assuming the tables are correct, no combination of input is to
62 * trigger a cmn_err call.
64 * 2. These functions can't be allowed to be traced. To prevent this,
65 * all functions in the probe path (everything except instr_size()) must
66 * have names that begin with "dtrace_".
69 typedef enum dis_isize {
76 * get a byte from instruction stream
79 dtrace_dis_get_byte(void *p)
91 * Returns either the size of a given instruction, in bytes, or the size of that
92 * instruction's memory access (if any), depending on the value of `which'.
93 * If a programming error in the tables is detected, the system will panic to
94 * ease diagnosis. Invalid instructions will not be flagged. They will appear
95 * to have an instruction size between 1 and the actual size, and will be
96 * reported as having no memory impact.
100 dtrace_dis_isize(uchar_t *instr, dis_isize_t which, model_t model, int *rmindex)
104 uint_t mode = SIZE32;
107 mode = (model == DATAMODEL_LP64) ? SIZE64 : SIZE32;
110 x.d86_data = (void **)&instr;
111 x.d86_get_byte = dtrace_dis_get_byte;
112 x.d86_check_func = NULL;
114 if (dtrace_disx86(&x, mode) != 0)
117 if (which == DIS_ISIZE_INSTR)
118 sz = x.d86_len; /* length of the instruction */
120 sz = x.d86_memsize; /* length of memory operand */
123 *rmindex = x.d86_rmindex;
128 dtrace_instr_size(uchar_t *instr)
130 return (dtrace_dis_isize(instr, DIS_ISIZE_INSTR, DATAMODEL_NATIVE,