translate: few more ops and corner cases
[ia32rtools.git] / tools / mkbridge.c
... / ...
CommitLineData
1/*
2 * ia32rtools
3 * (C) notaz, 2013,2014
4 *
5 * This work is licensed under the terms of 3-clause BSD license.
6 * See COPYING file in the top-level directory.
7 */
8
9#include <stdio.h>
10#include <stdlib.h>
11#include <string.h>
12
13#include "my_assert.h"
14#include "my_str.h"
15
16#define ARRAY_SIZE(x) (sizeof(x) / sizeof(x[0]))
17#define IS(w, y) !strcmp(w, y)
18
19#include "protoparse.h"
20
21static const char *c_save_regs[] = { "ebx", "esi", "edi", "ebp" };
22
23static int is_x86_reg_saved(const char *reg)
24{
25 static const char *nosave_regs[] = { "eax", "edx", "ecx" };
26 int nosave = 0;
27 int r;
28
29 for (r = 0; r < ARRAY_SIZE(nosave_regs); r++)
30 if (strcmp(reg, nosave_regs[r]) == 0)
31 nosave = 1;
32
33 return !nosave;
34}
35
36// output decorated name
37static const char *pp_to_name(const struct parsed_proto *pp)
38{
39 static char buf[256];
40 char atval[16];
41
42 if (!pp->is_fastcall && pp->argc_reg != 0) {
43 // can only be handled by __cdecl C func
44 snprintf(buf, sizeof(buf), "_%s", pp->name);
45 return buf;
46 }
47
48 atval[0] = 0;
49 if (pp->is_stdcall) {
50 snprintf(atval, sizeof(atval), "@%d",
51 pp->argc * 4);
52 }
53 snprintf(buf, sizeof(buf), "%s%s%s",
54 pp->is_fastcall ? "@" : "_",
55 pp->name, atval);
56
57 return buf;
58}
59
60static void out_toasm_x86(FILE *f, const char *sym_out,
61 const struct parsed_proto *pp)
62{
63 int must_save = 0;
64 int sarg_ofs = 1; // stack offset to args, in DWORDs
65 int args_repushed = 0;
66 int argc_repush;
67 const char *name;
68 int i;
69
70 argc_repush = pp->argc;
71 if (pp->is_vararg)
72 argc_repush = ARRAY_SIZE(pp->arg); // hopefully enough?
73
74 for (i = 0; i < pp->argc; i++) {
75 if (pp->arg[i].reg != NULL)
76 must_save |= is_x86_reg_saved(pp->arg[i].reg);
77 }
78
79 name = pp_to_name(pp);
80 fprintf(f, ".global %s\n", name);
81 fprintf(f, "%s:\n", name);
82
83 if (pp->argc_reg == 0 || pp->is_fastcall) {
84 fprintf(f, "\t# %s\n",
85 pp->is_fastcall ? "__fastcall" :
86 (pp->is_stdcall ? "__stdcall" : "__cdecl"));
87 fprintf(f, "\tjmp %s\n\n", sym_out);
88 return;
89 }
90
91 if (pp->argc_stack == 0 && !must_save && !pp->is_stdcall
92 && !pp->is_vararg && !pp->has_retreg)
93 {
94 // load arg regs
95 for (i = 0; i < pp->argc; i++) {
96 fprintf(f, "\tmovl %d(%%esp), %%%s\n",
97 (i + sarg_ofs) * 4, pp->arg[i].reg);
98 }
99 fprintf(f, "\tjmp %s\n\n", sym_out);
100 return;
101 }
102
103 // asm_stack_args | saved_regs | ra | args_from_c
104
105 // save the regs
106 // because we don't always know what we are calling,
107 // be safe and save everything that has to be saved in __cdecl
108 for (i = 0; i < ARRAY_SIZE(c_save_regs); i++) {
109 fprintf(f, "\tpushl %%%s\n", c_save_regs[i]);
110 sarg_ofs++;
111 }
112
113 // reconstruct arg stack for asm
114 for (i = argc_repush - 1; i >= 0; i--) {
115 if (pp->arg[i].reg == NULL) {
116 fprintf(f, "\tmovl %d(%%esp), %%eax\n",
117 (i + sarg_ofs) * 4);
118 fprintf(f, "\tpushl %%eax\n");
119 sarg_ofs++;
120 args_repushed++;
121 }
122 }
123
124 // load arg regs
125 for (i = 0; i < pp->argc; i++) {
126 if (pp->arg[i].reg != NULL) {
127 fprintf(f, "\tmovl %d(%%esp), %%%s\n",
128 (i + sarg_ofs) * 4, pp->arg[i].reg);
129 if (pp->arg[i].type.is_retreg)
130 fprintf(f, "\tmovl (%%%s), %%%s\n",
131 pp->arg[i].reg, pp->arg[i].reg);
132 }
133 }
134
135 fprintf(f, "\n\t# %s\n", pp->is_stdcall ? "__stdcall" : "__cdecl");
136 fprintf(f, "\tcall %s\n\n", sym_out);
137
138 if (args_repushed && !pp->is_stdcall) {
139 fprintf(f, "\tadd $%d,%%esp\n", args_repushed * 4);
140 sarg_ofs -= args_repushed;
141 }
142
143 // update the retreg regs
144 if (pp->has_retreg) {
145 for (i = 0; i < pp->argc; i++) {
146 if (pp->arg[i].type.is_retreg) {
147 fprintf(f, "\tmovl %d(%%esp), %%ecx\n"
148 "\tmovl %%%s, (%%ecx)\n",
149 (i + sarg_ofs) * 4, pp->arg[i].reg);
150 }
151 }
152 }
153
154 // restore regs
155 for (i = ARRAY_SIZE(c_save_regs) - 1; i >= 0; i--)
156 fprintf(f, "\tpopl %%%s\n", c_save_regs[i]);
157
158 fprintf(f, "\tret\n\n");
159}
160
161static void out_fromasm_x86(FILE *f, const char *sym,
162 const struct parsed_proto *pp)
163{
164 int reg_ofs[ARRAY_SIZE(pp->arg)];
165 int sarg_ofs = 1; // stack offset to args, in DWORDs
166 int saved_regs = 0;
167 int ecx_ofs = -1;
168 int edx_ofs = -1;
169 int c_is_stdcall;
170 int argc_repush;
171 int stack_args;
172 int ret64;
173 int i;
174
175 argc_repush = pp->argc;
176 stack_args = pp->argc_stack;
177 if (pp->is_vararg) {
178 argc_repush = ARRAY_SIZE(pp->arg); // hopefully enough?
179 stack_args = argc_repush - pp->argc_reg;
180 }
181
182 ret64 = strstr(pp->ret_type.name, "int64") != NULL;
183
184 fprintf(f, "# %s",
185 pp->is_fastcall ? "__fastcall" :
186 (pp->is_stdcall ? "__stdcall" : "__cdecl"));
187 if (ret64)
188 fprintf(f, " ret64");
189 fprintf(f, "\n.global %s\n", sym);
190 fprintf(f, "%s:\n", sym);
191
192 if ((pp->argc_reg == 0 || pp->is_fastcall)
193 && !IS(pp->name, "storm_491")) // wants edx save :(
194 {
195 fprintf(f, "\tjmp %s\n\n", pp_to_name(pp));
196 return;
197 }
198
199 c_is_stdcall = (pp->argc_reg == 0 && pp->is_stdcall);
200
201 // at least sc sub_47B150 needs edx to be preserved
202 // int64 returns use edx:eax - no edx save
203 // we use ecx also as scratch
204 fprintf(f, "\tpushl %%ecx\n");
205 saved_regs++;
206 sarg_ofs++;
207 ecx_ofs = sarg_ofs;
208 if (!ret64) {
209 fprintf(f, "\tpushl %%edx\n");
210 saved_regs++;
211 sarg_ofs++;
212 edx_ofs = sarg_ofs;
213 }
214
215 // need space for retreg args
216 if (pp->has_retreg) {
217 for (i = 0; i < pp->argc; i++) {
218 if (!pp->arg[i].type.is_retreg)
219 continue;
220 if (IS(pp->arg[i].reg, "ecx") && ecx_ofs >= 0) {
221 reg_ofs[i] = ecx_ofs;
222 continue;
223 }
224 if (IS(pp->arg[i].reg, "edx") && edx_ofs >= 0) {
225 reg_ofs[i] = edx_ofs;
226 continue;
227 }
228 fprintf(f, "\tpushl %%%s\n", pp->arg[i].reg);
229 saved_regs++;
230 sarg_ofs++;
231 reg_ofs[i] = sarg_ofs;
232 }
233 }
234
235 // construct arg stack
236 for (i = argc_repush - 1; i >= 0; i--) {
237 if (pp->arg[i].reg == NULL) {
238 fprintf(f, "\tmovl %d(%%esp), %%ecx\n",
239 (sarg_ofs + stack_args - 1) * 4);
240 fprintf(f, "\tpushl %%ecx\n");
241 stack_args--;
242 }
243 else {
244 const char *reg = pp->arg[i].reg;
245 if (pp->arg[i].type.is_retreg) {
246 reg = "ecx";
247 fprintf(f, "\tlea %d(%%esp), %%ecx\n",
248 (sarg_ofs - reg_ofs[i]) * 4);
249 }
250 else if (IS(reg, "ecx"))
251 // must reload original ecx
252 fprintf(f, "\tmovl %d(%%esp), %%ecx\n",
253 (sarg_ofs - 2) * 4);
254
255 fprintf(f, "\tpushl %%%s\n", reg);
256 }
257 sarg_ofs++;
258 }
259
260 fprintf(f, "\n\tcall %s\n\n", pp_to_name(pp));
261
262 if (!c_is_stdcall && sarg_ofs > saved_regs + 1)
263 fprintf(f, "\tadd $%d,%%esp\n",
264 (sarg_ofs - (saved_regs + 1)) * 4);
265
266 // pop retregs
267 if (pp->has_retreg) {
268 for (i = pp->argc - 1; i >= 0; i--) {
269 if (!pp->arg[i].type.is_retreg)
270 continue;
271 if (IS(pp->arg[i].reg, "ecx") && ecx_ofs >= 0) {
272 continue;
273 }
274 if (IS(pp->arg[i].reg, "edx") && edx_ofs >= 0) {
275 continue;
276 }
277 fprintf(f, "\tpopl %%%s\n", pp->arg[i].reg);
278 }
279 }
280
281 if (!ret64)
282 fprintf(f, "\tpopl %%edx\n");
283 fprintf(f, "\tpopl %%ecx\n");
284
285 if (pp->is_stdcall && pp->argc_stack)
286 fprintf(f, "\tret $%d\n\n", pp->argc_stack * 4);
287 else
288 fprintf(f, "\tret\n\n");
289}
290
291int main(int argc, char *argv[])
292{
293 FILE *fout, *fsyms_to, *fsyms_from, *fhdr;
294 const struct parsed_proto *pp;
295 char line[256];
296 char sym_noat[256];
297 char sym[256];
298 char *p;
299 int ret = 1;
300
301 if (argc != 5) {
302 printf("usage:\n%s <bridge.s> <toasm_symf> <fromasm_symf> <hdrf>\n",
303 argv[0]);
304 return 1;
305 }
306
307 hdrfn = argv[4];
308 fhdr = fopen(hdrfn, "r");
309 my_assert_not(fhdr, NULL);
310
311 fsyms_from = fopen(argv[3], "r");
312 my_assert_not(fsyms_from, NULL);
313
314 fsyms_to = fopen(argv[2], "r");
315 my_assert_not(fsyms_to, NULL);
316
317 fout = fopen(argv[1], "w");
318 my_assert_not(fout, NULL);
319
320 fprintf(fout, ".text\n\n");
321 fprintf(fout, "# to asm\n\n");
322
323 while (fgets(line, sizeof(line), fsyms_to))
324 {
325 next_word(sym, sizeof(sym), line);
326 if (sym[0] == 0 || sym[0] == ';' || sym[0] == '#')
327 continue;
328
329 // IDA asm doesn't do '@' notation..
330 strcpy(sym_noat, sym);
331 p = strchr(sym_noat, '@');
332 if (p != NULL)
333 *p = 0;
334
335 pp = proto_parse(fhdr, sym_noat, 0);
336 if (pp == NULL)
337 goto out;
338
339 out_toasm_x86(fout, sym_noat, pp);
340 }
341
342 fprintf(fout, "# from asm\n\n");
343
344 while (fgets(line, sizeof(line), fsyms_from))
345 {
346 next_word(sym, sizeof(sym), line);
347 if (sym[0] == 0 || sym[0] == ';' || sym[0] == '#')
348 continue;
349
350 pp = proto_parse(fhdr, sym, 0);
351 if (pp == NULL)
352 goto out;
353
354 out_fromasm_x86(fout, sym, pp);
355 }
356
357 ret = 0;
358out:
359 fclose(fout);
360 fclose(fsyms_to);
361 fclose(fsyms_from);
362 fclose(fhdr);
363 if (ret)
364 remove(argv[1]);
365
366 return ret;
367}