8 #define ARRAY_SIZE(x) (sizeof(x) / sizeof(x[0]))
9 #define IS(w, y) !strcmp(w, y)
11 #include "protoparse.h"
13 static int is_x86_reg_saved(const char *reg)
15 static const char *nosave_regs[] = { "eax", "edx", "ecx" };
19 for (r = 0; r < ARRAY_SIZE(nosave_regs); r++)
20 if (strcmp(reg, nosave_regs[r]) == 0)
26 static void out_toasm_x86(FILE *f, const char *sym_in,
27 const char *sym_out, const struct parsed_proto *pp)
30 int sarg_ofs = 1; // stack offset to args, in DWORDs
31 int args_repushed = 0;
35 argc_repush = pp->argc;
37 argc_repush = ARRAY_SIZE(pp->arg); // hopefully enough?
39 for (i = 0; i < pp->argc; i++) {
40 if (pp->arg[i].reg != NULL)
41 must_save |= is_x86_reg_saved(pp->arg[i].reg);
44 fprintf(f, ".global %s%s\n", pp->is_fastcall ? "@" : "_", sym_in);
45 fprintf(f, "%s%s:\n", pp->is_fastcall ? "@" : "_", sym_in);
47 if (pp->argc_reg == 0 || pp->is_fastcall) {
48 fprintf(f, "\t# %s\n",
49 pp->is_fastcall ? "__fastcall" :
50 (pp->is_stdcall ? "__stdcall" : "__cdecl"));
51 fprintf(f, "\tjmp %s\n\n", sym_out);
55 if (pp->argc_stack == 0 && !must_save && !pp->is_stdcall
59 for (i = 0; i < pp->argc; i++) {
60 fprintf(f, "\tmovl %d(%%esp), %%%s\n",
61 (i + sarg_ofs) * 4, pp->arg[i].reg);
63 fprintf(f, "\tjmp %s\n\n", sym_out);
68 for (i = 0; i < pp->argc; i++) {
69 if (pp->arg[i].reg != NULL && is_x86_reg_saved(pp->arg[i].reg)) {
70 fprintf(f, "\tpushl %%%s\n", pp->arg[i].reg);
75 // reconstruct arg stack
76 for (i = argc_repush - 1; i >= 0; i--) {
77 if (pp->arg[i].reg == NULL) {
78 fprintf(f, "\tmovl %d(%%esp), %%eax\n",
80 fprintf(f, "\tpushl %%eax\n");
85 // my_assert(args_repushed, pp->argc_stack);
88 for (i = 0; i < pp->argc; i++) {
89 if (pp->arg[i].reg != NULL) {
90 fprintf(f, "\tmovl %d(%%esp), %%%s\n",
91 (i + sarg_ofs) * 4, pp->arg[i].reg);
95 fprintf(f, "\n\t# %s\n", pp->is_stdcall ? "__stdcall" : "__cdecl");
96 fprintf(f, "\tcall %s\n\n", sym_out);
98 if (args_repushed && !pp->is_stdcall)
99 fprintf(f, "\tadd $%d,%%esp\n", args_repushed * 4);
102 for (i = pp->argc - 1; i >= 0; i--) {
103 if (pp->arg[i].reg != NULL && is_x86_reg_saved(pp->arg[i].reg))
104 fprintf(f, "\tpopl %%%s\n", pp->arg[i].reg);
107 fprintf(f, "\tret\n\n");
110 static void out_fromasm_x86(FILE *f, const char *sym,
111 const struct parsed_proto *pp)
113 int sarg_ofs = 1; // stack offset to args, in DWORDs
120 argc_repush = pp->argc;
121 stack_args = pp->argc_stack;
123 argc_repush = ARRAY_SIZE(pp->arg); // hopefully enough?
124 stack_args = argc_repush - pp->argc_reg;
127 ret64 = strstr(pp->ret_type.name, "int64") != NULL;
130 pp->is_fastcall ? "__fastcall" :
131 (pp->is_stdcall ? "__stdcall" : "__cdecl"));
133 fprintf(f, " ret64");
134 fprintf(f, "\n.global %s\n", sym);
135 fprintf(f, "%s:\n", sym);
137 if (pp->argc_reg == 0 || pp->is_fastcall) {
138 fprintf(f, "\tjmp %s%s",
139 pp->is_fastcall ? "@" : "_", sym);
140 if (pp->is_stdcall && pp->argc > 0)
141 fprintf(f, "@%d", pp->argc * 4);
146 // at least sc sub_47B150 needs edx to be preserved
147 // int64 returns use edx:eax - no edx save
148 // we use ecx also as scratch
149 fprintf(f, "\tpushl %%ecx\n");
153 fprintf(f, "\tpushl %%edx\n");
158 // construct arg stack
159 for (i = argc_repush - 1; i >= 0; i--) {
160 if (pp->arg[i].reg == NULL) {
161 fprintf(f, "\tmovl %d(%%esp), %%ecx\n",
162 (sarg_ofs + stack_args - 1) * 4);
163 fprintf(f, "\tpushl %%ecx\n");
167 if (IS(pp->arg[i].reg, "ecx"))
168 // must reload original ecx
169 fprintf(f, "\tmovl %d(%%esp), %%ecx\n",
172 fprintf(f, "\tpushl %%%s\n", pp->arg[i].reg);
177 // no worries about calling conventions - always __cdecl
178 fprintf(f, "\n\tcall _%s\n\n", sym);
180 if (sarg_ofs > saved_regs + 1)
181 fprintf(f, "\tadd $%d,%%esp\n",
182 (sarg_ofs - (saved_regs + 1)) * 4);
185 fprintf(f, "\tpopl %%edx\n");
186 fprintf(f, "\tpopl %%ecx\n");
188 if (pp->is_stdcall && pp->argc_stack)
189 fprintf(f, "\tret $%d\n\n", pp->argc_stack * 4);
191 fprintf(f, "\tret\n\n");
194 int main(int argc, char *argv[])
196 FILE *fout, *fsyms_to, *fsyms_from, *fhdr;
197 const struct parsed_proto *pp;
205 printf("usage:\n%s <bridge.s> <toasm_symf> <fromasm_symf> <hdrf>\n",
211 fhdr = fopen(hdrfn, "r");
212 my_assert_not(fhdr, NULL);
214 fsyms_from = fopen(argv[3], "r");
215 my_assert_not(fsyms_from, NULL);
217 fsyms_to = fopen(argv[2], "r");
218 my_assert_not(fsyms_to, NULL);
220 fout = fopen(argv[1], "w");
221 my_assert_not(fout, NULL);
223 fprintf(fout, ".text\n\n");
224 fprintf(fout, "# to asm\n\n");
226 while (fgets(line, sizeof(line), fsyms_to))
228 next_word(sym, sizeof(sym), line);
229 if (sym[0] == 0 || sym[0] == ';' || sym[0] == '#')
232 // IDA asm doesn't do '@' notation..
233 strcpy(sym_noat, sym);
234 p = strchr(sym_noat, '@');
238 pp = proto_parse(fhdr, sym_noat, 0);
242 out_toasm_x86(fout, sym, sym_noat, pp);
245 fprintf(fout, "# from asm\n\n");
247 while (fgets(line, sizeof(line), fsyms_from))
249 next_word(sym, sizeof(sym), line);
250 if (sym[0] == 0 || sym[0] == ';' || sym[0] == '#')
253 pp = proto_parse(fhdr, sym, 0);
257 out_fromasm_x86(fout, sym, pp);