xref: /original-bsd/sys/tahoe/inline/machdep.c (revision 1a56dd2c)
1 /*
2  * Copyright (c) 1984 Regents of the University of California.
3  * All rights reserved.  The Berkeley software License Agreement
4  * specifies the terms and conditions for redistribution.
5  */
6 
7 #ifndef lint
8 static char sccsid[] = "@(#)machdep.c	1.3 (Berkeley) 02/24/86";
9 #endif
10 
11 #include <stdio.h>
12 #include <ctype.h>
13 #include "inline.h"
14 
15 extern char *strcpy();
16 extern char *strcat();
17 extern char *index();
18 
19 /*
20  * The routines and tables in this file must be rewritten
21  * for each new machine that this program is ported to.
22  */
23 
24 /*
25  * Instruction stop table.
26  * All instructions that implicitly modify any of the temporary
27  * registers, change control flow, or implicitly loop must be
28  * listed in this table. It is used to find the end of a basic
29  * block when scanning backwards through the instruction stream
30  * trying to merge the inline expansion.
31  */
32 struct inststoptbl inststoptable[] = {
33 /* control */
34 	{ "bbssi" }, { "bcc" }, { "bcs" }, { "beql" }, { "beqlu" },
35 	{ "bgeq" }, { "bgequ" }, { "bgtr" }, { "bgtru" }, { "bleq" },
36 	{ "blequ" }, { "blss" }, { "blssu" }, { "bneq" }, { "bnequ" },
37 	{ "brb" }, { "brw" }, { "bvc" }, { "bvs" }, { "jmp" },
38 /* jump versions of control */
39 	{ "jbc" }, { "jbs" }, { "jeql" }, { "jeqlu" },
40 	{ "jgeq" }, { "jgequ" }, { "jgtr" }, { "jgtru" }, { "jleq" },
41 	{ "jlequ" }, { "jlss" }, { "jlssu" }, { "jneq" }, { "jnequ" },
42 	{ "jcc" }, { "jcs" }, { "jvc" }, { "jvs" }, { "jbr" },
43 /* multiple registers */
44 	{ "loadr" },
45 /* bit field */
46 	{ "bbc" }, { "bbs" },
47 /* character string and block move */
48 	{ "cmps2" }, { "cmps3" }, { "movblk" }, { "movs2" }, { "movs3" },
49 /* procedure call */
50 	{ "callf" }, { "calls" }, { "ret" },
51 /* loop control */
52 	{ "aobleq" }, { "aoblss" }, { "casel" },
53 /* privileged and miscellaneous */
54 	{ "bpt" }, { "halt" }, { "kcall" }, { "ldpctx" }, { "rei" },
55 	{ "svpctx" },
56 	{ "" }
57 };
58 
59 /*
60  * Check to see if a line is a candidate for replacement.
61  * Return pointer to name to be looked up in pattern table.
62  */
63 char *
64 doreplaceon(cp)
65 	char *cp;
66 {
67 
68 	if (bcmp(cp, "callf\t", 6))
69 		return (0);
70 	if ((cp = index(cp + 6, ',')) == 0)
71 		return (0);
72 	return (++cp);
73 }
74 
75 /*
76  * Find out how many arguments the function is being called with.
77  * A return value of -1 indicates that the count can't be determined.
78  */
79 countargs(cp)
80 	char *cp;
81 {
82 	int i;
83 
84 	if ((cp = index(cp, '$')) == 0)
85 		return (-1);
86 	if (!isdigit(*++cp) || (i = atoi(cp)) == -1)
87 		return (-1);
88 	return (i/4 - 1);
89 }
90 
91 /*
92  * Find the next argument to the function being expanded.
93  */
94 nextarg(argc, argv)
95 	int argc;
96 	char *argv[];
97 {
98 	register char *lastarg = argv[2];
99 
100 	if (argc == 3 &&
101 	    bcmp(argv[0], "mov", 3) == 0 &&
102 	    bcmp(argv[1], "(sp)+", 6) == 0 &&
103 	    lastarg[0] == 'r' && isdigit(lastarg[1]) && lastarg[2] == '\0')
104 		return (lastarg[1] - '0');
105 	return (-1);
106 }
107 
108 /*
109  * Determine whether the current line pushes an argument.
110  */
111 ispusharg(argc, argv)
112 	int argc;
113 	char *argv[];
114 {
115 
116 	if (argc < 2)
117 		return (0);
118 	if (argc == 2 && bcmp(argv[0], "push", 4) == 0)
119 		return (1);
120 	if (bcmp(argv[argc - 1], "-(sp)", 6) == 0)
121 		return (1);
122 	return (0);
123 }
124 
125 /*
126  * Determine which (if any) registers are modified
127  * Return register number that is modified, -1 if none are modified.
128  */
129 modifies(argc, argv)
130 	int argc;
131 	char *argv[];
132 {
133 	register char *lastarg = argv[argc - 1];
134 
135 	/*
136 	 * For the tahoe all we care about are r0 to r5
137 	 */
138 	if (lastarg[0] == 'r' && isdigit(lastarg[1]) && lastarg[2] == '\0')
139 		return (lastarg[1] - '0');
140 	return (-1);
141 }
142 
143 /*
144  * Rewrite the instruction in (argc, argv) to store its
145  * contents into arg instead of onto the stack. The new
146  * instruction is placed in the buffer that is provided.
147  */
148 rewrite(instbuf, argc, argv, target)
149 	char *instbuf;
150 	int argc;
151 	char *argv[];
152 	int target;
153 {
154 
155 	switch (argc) {
156 	case 0:
157 		instbuf[0] = '\0';
158 		fprintf(stderr, "blank line to rewrite?\n");
159 		return;
160 	case 1:
161 		sprintf(instbuf, "\t%s\n", argv[0]);
162 		fprintf(stderr, "rewrite?-> %s", instbuf);
163 		return;
164 	case 2:
165 		if (bcmp(argv[0], "push", 4) == 0) {
166 			sprintf(instbuf, "\tmov%s\t%s,r%d\n",
167 				&argv[0][4], argv[1], target);
168 			return;
169 		}
170 		sprintf(instbuf, "\t%s\tr%d\n", argv[0], target);
171 		return;
172 	case 3:
173 		sprintf(instbuf, "\t%s\t%s,r%d\n", argv[0], argv[1], target);
174 		return;
175 	case 4:
176 		sprintf(instbuf, "\t%s\t%s,%s,r%d\n",
177 			argv[0], argv[1], argv[2], target);
178 		return;
179 	case 5:
180 		sprintf(instbuf, "\t%s\t%s,%s,%s,r%d\n",
181 			argv[0], argv[1], argv[2], argv[3], target);
182 		return;
183 	default:
184 		sprintf(instbuf, "\t%s\t%s", argv[0], argv[1]);
185 		argc -= 2, argv += 2;
186 		while (argc-- > 0) {
187 			strcat(instbuf, ",");
188 			strcat(instbuf, *argv++);
189 		}
190 		strcat(instbuf, "\n");
191 		fprintf(stderr, "rewrite?-> %s", instbuf);
192 		return;
193 	}
194 }
195 
196 /*
197  * Do any necessary post expansion cleanup.
198  */
199 cleanup(numargs)
200 	int numargs;
201 {
202 
203 }
204