src/uae_cpu/cpuopti.c

/*
 * UAE - The Un*x Amiga Emulator
 *
 * cpuopti.c - Small optimizer for cpu*.s files
 *             Based on work by Tauno Taipaleenmaki
 *
 * Copyright 1996 Bernd Schmidt
 *
 * 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 of the License, 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <ctype.h>
#include <stdio.h>
#include <string.h>

#include "sysdeps.h"

struct line {
    struct line *next, *prev;
    int delet;
    char *data;
};

struct func {
    struct line *first_line, *last_line;
    int initial_offset;
};

static void oops(void)
{
    fprintf(stderr, "Don't know how to optimize this file.\n");
        exit(1);
}

static char * match(struct line *l, const char *m)
{
    char *str = l->data;
    int len = strlen(m);
    while (isspace(*str))
        str++;

    if (strncmp(str, m, len) != 0)
        return NULL;
    return str + len;
}

static int insn_references_reg (struct line *l, char *reg)
{
    if (reg[0] != 'e') {
        fprintf(stderr, "Unknown register?!?\n");
        exit(1);
    }
    if (strstr (l->data, reg) != 0)
        return 1;
    if (strstr (l->data, reg+1) != 0)
        return 1;
    if (strcmp (reg, "eax") == 0
        && (strstr (l->data, "%al") != 0 || strstr (l->data, "%ah") != 0))
        return 1;
    if (strcmp (reg, "ebx") == 0
        && (strstr (l->data, "%bl") != 0 || strstr (l->data, "%bh") != 0))
        return 1;
    if (strcmp (reg, "ecx") == 0
        && (strstr (l->data, "%cl") != 0 || strstr (l->data, "%ch") != 0))
        return 1;
    if (strcmp (reg, "edx") == 0
        && (strstr (l->data, "%dl") != 0 || strstr (l->data, "%dh") != 0))
        return 1;
    return 0;
}

static void do_function(struct func *f)
{
    int v;
    int pops_at_end = 0;
    struct line *l, *l1, *fl, *l2;
    char *s, *s2;
    int in_pop_area = 1;

    f->initial_offset = 0;

    l = f->last_line;
    fl = f->first_line;

    if (match(l,".LFE"))
        l = l->prev;
    if (!match(l,"ret"))
        oops();

    while (!match(fl, "op_"))
        fl = fl->next;
    fl = fl->next;

    /* Try reordering the insns at the end of the function so that the
     * pops are all at the end. */
    l2 = l->prev;
    /* Tolerate one stack adjustment */
    if (match (l2, "addl $") && strstr(l2->data, "esp") != 0)
        l2 = l2->prev;
    for (;;) {
        char *forbidden_reg;
        struct line *l3, *l4;

        while (match (l2, "popl %"))
            l2 = l2->prev;

        l3 = l2;
        for (;;) {
            forbidden_reg = match (l3, "popl %");
            if (forbidden_reg)
                break;
            if (l3 == fl)
                goto reordered;
            /* Jumps and labels put an end to our attempts... */
            if (strstr (l3->data, ".L") != 0)
                goto reordered;
            /* Likewise accesses to the stack pointer... */
            if (strstr (l3->data, "esp") != 0)
                goto reordered;
            /* Function calls... */
            if (strstr (l3->data, "call") != 0)
                goto reordered;
            l3 = l3->prev;
        }
        if (l3 == l2)
            exit(1);
        for (l4 = l2; l4 != l3; l4 = l4->prev) {
            /* The register may not be referenced by any of the insns that we
             * move the popl past */
            if (insn_references_reg (l4, forbidden_reg))
                goto reordered;
        }
        l3->prev->next = l3->next;
        l3->next->prev = l3->prev;
        l2->next->prev = l3;
        l3->next = l2->next;
        l2->next = l3;
        l3->prev = l2;
    }
reordered:

    l = l->prev;

    s = match (l, "addl $");
    s2 = match (fl, "subl $");

    l1 = l;
    if (s == 0) {
        char *t = match (l, "popl %");
        if (t != 0 && (strcmp (t, "ecx") == 0 || strcmp (t, "edx") == 0)) {
            s = "4,%esp";
            l = l->prev;
            t = match (l, "popl %");
            if (t != 0 && (strcmp (t, "ecx") == 0 || strcmp (t, "edx") == 0)) {
                s = "8,%esp";
                l = l->prev;
            }
        }
    } else {
        l = l->prev;
    }

    if (s && s2) {
        int v = 0;
        if (strcmp (s, s2) != 0) {
            fprintf (stderr, "Stack adjustment not matching.\n");
            return;
        }

        while (isdigit(*s)) {
            v = v * 10 + (*s) - '0';
            s++;
        }

        if (strcmp (s, ",%esp") != 0) {
            fprintf (stderr, "Not adjusting the stack pointer.\n");
            return;
        }
        f->initial_offset = v;
        fl->delet = 3;
        fl = fl->next;
        l1->delet = 2;
        l1 = l1->prev;
        while (l1 != l) {
            l1->delet = 1;
            l1 = l1->prev;
        }
    }

    while (in_pop_area) {
        char *popm, *pushm;
        popm = match (l, "popl %");
        pushm = match (fl, "pushl %");
        if (popm && pushm && strcmp(pushm, popm) == 0) {
            pops_at_end++;
            fl->delet = l->delet = 1;
        } else
            in_pop_area = 0;
        l = l->prev;
        fl = fl->next;
    }
    if (f->initial_offset)
        f->initial_offset += 4 * pops_at_end;
}

static void output_function(struct func *f)
{
    struct line *l = f->first_line;

    while (l) {
        switch (l->delet) {
         case 1:
            break;
         case 0:
            printf("%s\n", l->data);
            break;
         case 2:
            if (f->initial_offset)
                printf("\taddl $%d,%%esp\n", f->initial_offset);
            break;
         case 3:
            if (f->initial_offset)
                printf("\tsubl $%d,%%esp\n", f->initial_offset);
            break;
        }
        l = l->next;
    }
}

int main(int argc, char **argv)
{
    FILE *infile = stdin;
    char tmp[4096];

#ifdef __mc68000__
    if(system("perl machdep/cpuopti")==-1) {
       perror("perl machdep/cpuopti");
       return 10;
   } else return 0;
#endif

    /* For debugging... */
    if (argc == 2)
        infile = fopen (argv[1], "r");

    for(;;) {
        char *s;

        if ((fgets(tmp, 4095, infile)) == NULL)
            break;

        s = strchr (tmp, '\n');
        if (s != NULL)
            *s = 0;

        if (strncmp(tmp, ".globl op_", 10) == 0) {
            struct line *first_line = NULL, *prev = NULL;
            struct line **nextp = &first_line;
            struct func f;
            int nr_rets = 0;
            int can_opt = 1;

            do {
                struct line *current;

                if (strcmp (tmp, "#APP") != 0 && strcmp (tmp, "#NO_APP") != 0) {
                    current = *nextp = (struct line *)malloc(sizeof (struct line));
                    nextp = &current->next;
                    current->prev = prev; prev = current;
                    current->next = NULL;
                    current->delet = 0;
                    current->data = strdup (tmp);
                    if (match (current, "movl %esp,%ebp") || match (current, "enter")) {
                        fprintf (stderr, "GCC failed to eliminate fp: %s\n", first_line->data);
                        can_opt = 0;
                    }

                    if (match (current, "ret"))
                        nr_rets++;
                }
                if ((fgets(tmp, 4095, infile)) == NULL)
                    oops();
                s = strchr (tmp, '\n');
                if (s != NULL)
                    *s = 0;
            } while (strncmp (tmp,".Lfe", 4) != 0);

            f.first_line = first_line;
            f.last_line = prev;

            if (nr_rets == 1 && can_opt)
                do_function(&f);
            /*else
                fprintf(stderr, "Too many RET instructions: %s\n", first_line->data);*/
            output_function(&f);
        }
        printf("%s\n", tmp);
    }
    return 0;
}
Revision:	1.3
Committed:	2012-03-30T01:25:46Z (12 years, 7 months ago) by asvitkine
Content type:	text/plain
Branch:	MAIN
CVS Tags:	HEAD
Changes since 1.2:	+14 -0 lines
Log Message:	Add GPLv2 notices to files from UAE Amiga Emulator, as retrieved from the COPYING file of uae-0.8.29, retrieved from http://www.amigaemulator.org/ via uae-0.8.29.tar.bz2 (MD5 = 54abbabb5e8580b679c52de019141d61).
#	Content
1	/*
2	* UAE - The Un*x Amiga Emulator
3	*
4	* cpuopti.c - Small optimizer for cpu*.s files
5	* Based on work by Tauno Taipaleenmaki
6	*
7	* Copyright 1996 Bernd Schmidt
8	*
9	* This program is free software; you can redistribute it and/or modify
10	* it under the terms of the GNU General Public License as published by
11	* the Free Software Foundation; either version 2 of the License, or
12	* (at your option) any later version.
13	*
14	* This program is distributed in the hope that it will be useful,
15	* but WITHOUT ANY WARRANTY; without even the implied warranty of
16	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17	* GNU General Public License for more details.
18	*
19	* You should have received a copy of the GNU General Public License
20	* along with this program; if not, write to the Free Software
21	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22	*/
23
24	#include <ctype.h>
25	#include <stdio.h>
26	#include <string.h>
27
28	#include "sysdeps.h"
29
30	struct line {
31	struct line next, prev;
32	int delet;
33	char *data;
34	};
35
36	struct func {
37	struct line first_line, last_line;
38	int initial_offset;
39	};
40
41	static void oops(void)
42	{
43	fprintf(stderr, "Don't know how to optimize this file.\n");
44	exit(1);
45	}
46
47	static char * match(struct line l, const char m)
48	{
49	char *str = l->data;
50	int len = strlen(m);
51	while (isspace(*str))
52	str++;
53
54	if (strncmp(str, m, len) != 0)
55	return NULL;
56	return str + len;
57	}
58
59	static int insn_references_reg (struct line l, char reg)
60	{
61	if (reg[0] != 'e') {
62	fprintf(stderr, "Unknown register?!?\n");
63	exit(1);
64	}
65	if (strstr (l->data, reg) != 0)
66	return 1;
67	if (strstr (l->data, reg+1) != 0)
68	return 1;
69	if (strcmp (reg, "eax") == 0
70	&& (strstr (l->data, "%al") != 0 \|\| strstr (l->data, "%ah") != 0))
71	return 1;
72	if (strcmp (reg, "ebx") == 0
73	&& (strstr (l->data, "%bl") != 0 \|\| strstr (l->data, "%bh") != 0))
74	return 1;
75	if (strcmp (reg, "ecx") == 0
76	&& (strstr (l->data, "%cl") != 0 \|\| strstr (l->data, "%ch") != 0))
77	return 1;
78	if (strcmp (reg, "edx") == 0
79	&& (strstr (l->data, "%dl") != 0 \|\| strstr (l->data, "%dh") != 0))
80	return 1;
81	return 0;
82	}
83
84	static void do_function(struct func *f)
85	{
86	int v;
87	int pops_at_end = 0;
88	struct line l, l1, fl, l2;
89	char s, s2;
90	int in_pop_area = 1;
91
92	f->initial_offset = 0;
93
94	l = f->last_line;
95	fl = f->first_line;
96
97	if (match(l,".LFE"))
98	l = l->prev;
99	if (!match(l,"ret"))
100	oops();
101
102	while (!match(fl, "op_"))
103	fl = fl->next;
104	fl = fl->next;
105
106	/* Try reordering the insns at the end of the function so that the
107	* pops are all at the end. */
108	l2 = l->prev;
109	/* Tolerate one stack adjustment */
110	if (match (l2, "addl $") && strstr(l2->data, "esp") != 0)
111	l2 = l2->prev;
112	for (;;) {
113	char *forbidden_reg;
114	struct line l3, l4;
115
116	while (match (l2, "popl %"))
117	l2 = l2->prev;
118
119	l3 = l2;
120	for (;;) {
121	forbidden_reg = match (l3, "popl %");
122	if (forbidden_reg)
123	break;
124	if (l3 == fl)
125	goto reordered;
126	/* Jumps and labels put an end to our attempts... */
127	if (strstr (l3->data, ".L") != 0)
128	goto reordered;
129	/* Likewise accesses to the stack pointer... */
130	if (strstr (l3->data, "esp") != 0)
131	goto reordered;
132	/* Function calls... */
133	if (strstr (l3->data, "call") != 0)
134	goto reordered;
135	l3 = l3->prev;
136	}
137	if (l3 == l2)
138	exit(1);
139	for (l4 = l2; l4 != l3; l4 = l4->prev) {
140	/* The register may not be referenced by any of the insns that we
141	* move the popl past */
142	if (insn_references_reg (l4, forbidden_reg))
143	goto reordered;
144	}
145	l3->prev->next = l3->next;
146	l3->next->prev = l3->prev;
147	l2->next->prev = l3;
148	l3->next = l2->next;
149	l2->next = l3;
150	l3->prev = l2;
151	}
152	reordered:
153
154	l = l->prev;
155
156	s = match (l, "addl $");
157	s2 = match (fl, "subl $");
158
159	l1 = l;
160	if (s == 0) {
161	char *t = match (l, "popl %");
162	if (t != 0 && (strcmp (t, "ecx") == 0 \|\| strcmp (t, "edx") == 0)) {
163	s = "4,%esp";
164	l = l->prev;
165	t = match (l, "popl %");
166	if (t != 0 && (strcmp (t, "ecx") == 0 \|\| strcmp (t, "edx") == 0)) {
167	s = "8,%esp";
168	l = l->prev;
169	}
170	}
171	} else {
172	l = l->prev;
173	}
174
175	if (s && s2) {
176	int v = 0;
177	if (strcmp (s, s2) != 0) {
178	fprintf (stderr, "Stack adjustment not matching.\n");
179	return;
180	}
181
182	while (isdigit(*s)) {
183	v = v * 10 + (*s) - '0';
184	s++;
185	}
186
187	if (strcmp (s, ",%esp") != 0) {
188	fprintf (stderr, "Not adjusting the stack pointer.\n");
189	return;
190	}
191	f->initial_offset = v;
192	fl->delet = 3;
193	fl = fl->next;
194	l1->delet = 2;
195	l1 = l1->prev;
196	while (l1 != l) {
197	l1->delet = 1;
198	l1 = l1->prev;
199	}
200	}
201
202	while (in_pop_area) {
203	char popm, pushm;
204	popm = match (l, "popl %");
205	pushm = match (fl, "pushl %");
206	if (popm && pushm && strcmp(pushm, popm) == 0) {
207	pops_at_end++;
208	fl->delet = l->delet = 1;
209	} else
210	in_pop_area = 0;
211	l = l->prev;
212	fl = fl->next;
213	}
214	if (f->initial_offset)
215	f->initial_offset += 4 * pops_at_end;
216	}
217
218	static void output_function(struct func *f)
219	{
220	struct line *l = f->first_line;
221
222	while (l) {
223	switch (l->delet) {
224	case 1:
225	break;
226	case 0:
227	printf("%s\n", l->data);
228	break;
229	case 2:
230	if (f->initial_offset)
231	printf("\taddl $%d,%%esp\n", f->initial_offset);
232	break;
233	case 3:
234	if (f->initial_offset)
235	printf("\tsubl $%d,%%esp\n", f->initial_offset);
236	break;
237	}
238	l = l->next;
239	}
240	}
241
242	int main(int argc, char **argv)
243	{
244	FILE *infile = stdin;
245	char tmp[4096];
246
247	#ifdef __mc68000__
248	if(system("perl machdep/cpuopti")==-1) {
249	perror("perl machdep/cpuopti");
250	return 10;
251	} else return 0;
252	#endif
253
254	/* For debugging... */
255	if (argc == 2)
256	infile = fopen (argv[1], "r");
257
258	for(;;) {
259	char *s;
260
261	if ((fgets(tmp, 4095, infile)) == NULL)
262	break;
263
264	s = strchr (tmp, '\n');
265	if (s != NULL)
266	*s = 0;
267
268	if (strncmp(tmp, ".globl op_", 10) == 0) {
269	struct line first_line = NULL, prev = NULL;
270	struct line **nextp = &first_line;
271	struct func f;
272	int nr_rets = 0;
273	int can_opt = 1;
274
275	do {
276	struct line *current;
277
278	if (strcmp (tmp, "#APP") != 0 && strcmp (tmp, "#NO_APP") != 0) {
279	current = nextp = (struct line )malloc(sizeof (struct line));
280	nextp = &current->next;
281	current->prev = prev; prev = current;
282	current->next = NULL;
283	current->delet = 0;
284	current->data = strdup (tmp);
285	if (match (current, "movl %esp,%ebp") \|\| match (current, "enter")) {
286	fprintf (stderr, "GCC failed to eliminate fp: %s\n", first_line->data);
287	can_opt = 0;
288	}
289
290	if (match (current, "ret"))
291	nr_rets++;
292	}
293	if ((fgets(tmp, 4095, infile)) == NULL)
294	oops();
295	s = strchr (tmp, '\n');
296	if (s != NULL)
297	*s = 0;
298	} while (strncmp (tmp,".Lfe", 4) != 0);
299
300	f.first_line = first_line;
301	f.last_line = prev;
302
303	if (nr_rets == 1 && can_opt)
304	do_function(&f);
305	/*else
306	fprintf(stderr, "Too many RET instructions: %s\n", first_line->data);*/
307	output_function(&f);
308	}
309	printf("%s\n", tmp);
310	}
311	return 0;
312	}