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
 */

#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:	1.2
Committed:	2001-06-28T21:20:02Z (23 years, 5 months ago) by cebix
Content type:	text/plain
Branch:	MAIN
CVS Tags:	nigel-build-19, nigel-build-12, nigel-build-13, nigel-build-16, nigel-build-17, nigel-build-15, snapshot-15012002
Changes since 1.1:	+3 -3 lines
Log Message:	video_x.cpp supports resolution switching in windowed mode: the available resolutions are 512x384, 640x480, 800x600, 1024x768 and 1280x1024 (the prefs editor has to be updated to reflect this). The resolution selected in the prefs editor is used as the default, but it can be changed in the Monitors control panel. So far only tested with direct addressing.
#	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
10	#include <ctype.h>
11	#include <stdio.h>
12	#include <string.h>
13
14	#include "sysdeps.h"
15
16	struct line {
17	struct line next, prev;
18	int delet;
19	char *data;
20	};
21
22	struct func {
23	struct line first_line, last_line;
24	int initial_offset;
25	};
26
27	static void oops(void)
28	{
29	fprintf(stderr, "Don't know how to optimize this file.\n");
30	exit(1);
31	}
32
33	static char * match(struct line l, const char m)
34	{
35	char *str = l->data;
36	int len = strlen(m);
37	while (isspace(*str))
38	str++;
39
40	if (strncmp(str, m, len) != 0)
41	return NULL;
42	return str + len;
43	}
44
45	static int insn_references_reg (struct line l, char reg)
46	{
47	if (reg[0] != 'e') {
48	fprintf(stderr, "Unknown register?!?\n");
49	exit(1);
50	}
51	if (strstr (l->data, reg) != 0)
52	return 1;
53	if (strstr (l->data, reg+1) != 0)
54	return 1;
55	if (strcmp (reg, "eax") == 0
56	&& (strstr (l->data, "%al") != 0 \|\| strstr (l->data, "%ah") != 0))
57	return 1;
58	if (strcmp (reg, "ebx") == 0
59	&& (strstr (l->data, "%bl") != 0 \|\| strstr (l->data, "%bh") != 0))
60	return 1;
61	if (strcmp (reg, "ecx") == 0
62	&& (strstr (l->data, "%cl") != 0 \|\| strstr (l->data, "%ch") != 0))
63	return 1;
64	if (strcmp (reg, "edx") == 0
65	&& (strstr (l->data, "%dl") != 0 \|\| strstr (l->data, "%dh") != 0))
66	return 1;
67	return 0;
68	}
69
70	static void do_function(struct func *f)
71	{
72	int v;
73	int pops_at_end = 0;
74	struct line l, l1, fl, l2;
75	char s, s2;
76	int in_pop_area = 1;
77
78	f->initial_offset = 0;
79
80	l = f->last_line;
81	fl = f->first_line;
82
83	if (match(l,".LFE"))
84	l = l->prev;
85	if (!match(l,"ret"))
86	oops();
87
88	while (!match(fl, "op_"))
89	fl = fl->next;
90	fl = fl->next;
91
92	/* Try reordering the insns at the end of the function so that the
93	* pops are all at the end. */
94	l2 = l->prev;
95	/* Tolerate one stack adjustment */
96	if (match (l2, "addl $") && strstr(l2->data, "esp") != 0)
97	l2 = l2->prev;
98	for (;;) {
99	char *forbidden_reg;
100	struct line l3, l4;
101
102	while (match (l2, "popl %"))
103	l2 = l2->prev;
104
105	l3 = l2;
106	for (;;) {
107	forbidden_reg = match (l3, "popl %");
108	if (forbidden_reg)
109	break;
110	if (l3 == fl)
111	goto reordered;
112	/* Jumps and labels put an end to our attempts... */
113	if (strstr (l3->data, ".L") != 0)
114	goto reordered;
115	/* Likewise accesses to the stack pointer... */
116	if (strstr (l3->data, "esp") != 0)
117	goto reordered;
118	/* Function calls... */
119	if (strstr (l3->data, "call") != 0)
120	goto reordered;
121	l3 = l3->prev;
122	}
123	if (l3 == l2)
124	exit(1);
125	for (l4 = l2; l4 != l3; l4 = l4->prev) {
126	/* The register may not be referenced by any of the insns that we
127	* move the popl past */
128	if (insn_references_reg (l4, forbidden_reg))
129	goto reordered;
130	}
131	l3->prev->next = l3->next;
132	l3->next->prev = l3->prev;
133	l2->next->prev = l3;
134	l3->next = l2->next;
135	l2->next = l3;
136	l3->prev = l2;
137	}
138	reordered:
139
140	l = l->prev;
141
142	s = match (l, "addl $");
143	s2 = match (fl, "subl $");
144
145	l1 = l;
146	if (s == 0) {
147	char *t = match (l, "popl %");
148	if (t != 0 && (strcmp (t, "ecx") == 0 \|\| strcmp (t, "edx") == 0)) {
149	s = "4,%esp";
150	l = l->prev;
151	t = match (l, "popl %");
152	if (t != 0 && (strcmp (t, "ecx") == 0 \|\| strcmp (t, "edx") == 0)) {
153	s = "8,%esp";
154	l = l->prev;
155	}
156	}
157	} else {
158	l = l->prev;
159	}
160
161	if (s && s2) {
162	int v = 0;
163	if (strcmp (s, s2) != 0) {
164	fprintf (stderr, "Stack adjustment not matching.\n");
165	return;
166	}
167
168	while (isdigit(*s)) {
169	v = v * 10 + (*s) - '0';
170	s++;
171	}
172
173	if (strcmp (s, ",%esp") != 0) {
174	fprintf (stderr, "Not adjusting the stack pointer.\n");
175	return;
176	}
177	f->initial_offset = v;
178	fl->delet = 3;
179	fl = fl->next;
180	l1->delet = 2;
181	l1 = l1->prev;
182	while (l1 != l) {
183	l1->delet = 1;
184	l1 = l1->prev;
185	}
186	}
187
188	while (in_pop_area) {
189	char popm, pushm;
190	popm = match (l, "popl %");
191	pushm = match (fl, "pushl %");
192	if (popm && pushm && strcmp(pushm, popm) == 0) {
193	pops_at_end++;
194	fl->delet = l->delet = 1;
195	} else
196	in_pop_area = 0;
197	l = l->prev;
198	fl = fl->next;
199	}
200	if (f->initial_offset)
201	f->initial_offset += 4 * pops_at_end;
202	}
203
204	static void output_function(struct func *f)
205	{
206	struct line *l = f->first_line;
207
208	while (l) {
209	switch (l->delet) {
210	case 1:
211	break;
212	case 0:
213	printf("%s\n", l->data);
214	break;
215	case 2:
216	if (f->initial_offset)
217	printf("\taddl $%d,%%esp\n", f->initial_offset);
218	break;
219	case 3:
220	if (f->initial_offset)
221	printf("\tsubl $%d,%%esp\n", f->initial_offset);
222	break;
223	}
224	l = l->next;
225	}
226	}
227
228	int main(int argc, char **argv)
229	{
230	FILE *infile = stdin;
231	char tmp[4096];
232
233	#ifdef __mc68000__
234	if(system("perl machdep/cpuopti")==-1) {
235	perror("perl machdep/cpuopti");
236	return 10;
237	} else return 0;
238	#endif
239
240	/* For debugging... */
241	if (argc == 2)
242	infile = fopen (argv[1], "r");
243
244	for(;;) {
245	char *s;
246
247	if ((fgets(tmp, 4095, infile)) == NULL)
248	break;
249
250	s = strchr (tmp, '\n');
251	if (s != NULL)
252	*s = 0;
253
254	if (strncmp(tmp, ".globl op_", 10) == 0) {
255	struct line first_line = NULL, prev = NULL;
256	struct line **nextp = &first_line;
257	struct func f;
258	int nr_rets = 0;
259	int can_opt = 1;
260
261	do {
262	struct line *current;
263
264	if (strcmp (tmp, "#APP") != 0 && strcmp (tmp, "#NO_APP") != 0) {
265	current = nextp = (struct line )malloc(sizeof (struct line));
266	nextp = &current->next;
267	current->prev = prev; prev = current;
268	current->next = NULL;
269	current->delet = 0;
270	current->data = strdup (tmp);
271	if (match (current, "movl %esp,%ebp") \|\| match (current, "enter")) {
272	fprintf (stderr, "GCC failed to eliminate fp: %s\n", first_line->data);
273	can_opt = 0;
274	}
275
276	if (match (current, "ret"))
277	nr_rets++;
278	}
279	if ((fgets(tmp, 4095, infile)) == NULL)
280	oops();
281	s = strchr (tmp, '\n');
282	if (s != NULL)
283	*s = 0;
284	} while (strncmp (tmp,".Lfe", 4) != 0);
285
286	f.first_line = first_line;
287	f.last_line = prev;
288
289	if (nr_rets == 1 && can_opt)
290	do_function(&f);
291	/*else
292	fprintf(stderr, "Too many RET instructions: %s\n", first_line->data);*/
293	output_function(&f);
294	}
295	printf("%s\n", tmp);
296	}
297	return 0;
298	}