+/*
+ * ia32rtools
+ * (C) notaz, 2013,2014
+ *
+ * This work is licensed under the terms of 3-clause BSD license.
+ * See COPYING file in the top-level directory.
+ */
+
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "protoparse.h"
+static const char *c_save_regs[] = { "ebx", "esi", "edi", "ebp" };
+
static int is_x86_reg_saved(const char *reg)
{
static const char *nosave_regs[] = { "eax", "edx", "ecx" };
return !nosave;
}
-static void out_toasm_x86(FILE *f, char *sym, struct parsed_proto *pp)
+// output decorated name
+static const char *pp_to_name(const struct parsed_proto *pp)
+{
+ static char buf[256];
+ char atval[16];
+
+ if (!pp->is_fastcall && pp->argc_reg != 0) {
+ // can only be handled by __cdecl C func
+ snprintf(buf, sizeof(buf), "_%s", pp->name);
+ return buf;
+ }
+
+ atval[0] = 0;
+ if (pp->is_stdcall) {
+ snprintf(atval, sizeof(atval), "@%d",
+ pp->argc * 4);
+ }
+ snprintf(buf, sizeof(buf), "%s%s%s",
+ pp->is_fastcall ? "@" : "_",
+ pp->name, atval);
+
+ return buf;
+}
+
+static void out_toasm_x86(FILE *f, const char *sym_out,
+ const struct parsed_proto *pp)
{
int must_save = 0;
int sarg_ofs = 1; // stack offset to args, in DWORDs
int args_repushed = 0;
+ int argc_repush;
+ const char *name;
int i;
+ argc_repush = pp->argc;
+ if (pp->is_vararg)
+ argc_repush = ARRAY_SIZE(pp->arg); // hopefully enough?
+
for (i = 0; i < pp->argc; i++) {
if (pp->arg[i].reg != NULL)
must_save |= is_x86_reg_saved(pp->arg[i].reg);
}
- fprintf(f, ".global _%s\n", sym);
- fprintf(f, "_%s:\n", sym);
+ name = pp_to_name(pp);
+ fprintf(f, ".global %s\n", name);
+ fprintf(f, "%s:\n", name);
- if (pp->argc_reg == 0 && !pp->is_stdcall) {
- fprintf(f, "\tjmp %s\n\n", sym);
+ if (pp->argc_reg == 0 || pp->is_fastcall) {
+ fprintf(f, "\t# %s\n",
+ pp->is_fastcall ? "__fastcall" :
+ (pp->is_stdcall ? "__stdcall" : "__cdecl"));
+ fprintf(f, "\tjmp %s\n\n", sym_out);
return;
}
- if (pp->argc_stack == 0 && !must_save && !pp->is_stdcall) {
+ if (pp->argc_stack == 0 && !must_save && !pp->is_stdcall
+ && !pp->is_vararg && !pp->has_retreg)
+ {
// load arg regs
for (i = 0; i < pp->argc; i++) {
fprintf(f, "\tmovl %d(%%esp), %%%s\n",
(i + sarg_ofs) * 4, pp->arg[i].reg);
}
- fprintf(f, "\tjmp %s\n\n", sym);
+ fprintf(f, "\tjmp %s\n\n", sym_out);
return;
}
+ // asm_stack_args | saved_regs | ra | args_from_c
+
// save the regs
- for (i = 0; i < pp->argc; i++) {
- if (pp->arg[i].reg != NULL && is_x86_reg_saved(pp->arg[i].reg)) {
- fprintf(f, "\tpushl %%%s\n", pp->arg[i].reg);
- sarg_ofs++;
- }
+ // because we don't always know what we are calling,
+ // be safe and save everything that has to be saved in __cdecl
+ for (i = 0; i < ARRAY_SIZE(c_save_regs); i++) {
+ fprintf(f, "\tpushl %%%s\n", c_save_regs[i]);
+ sarg_ofs++;
}
- // reconstruct arg stack
- for (i = pp->argc - 1; i >= 0; i--) {
+ // reconstruct arg stack for asm
+ for (i = argc_repush - 1; i >= 0; i--) {
if (pp->arg[i].reg == NULL) {
fprintf(f, "\tmovl %d(%%esp), %%eax\n",
(i + sarg_ofs) * 4);
args_repushed++;
}
}
- my_assert(args_repushed, pp->argc_stack);
// load arg regs
for (i = 0; i < pp->argc; i++) {
if (pp->arg[i].reg != NULL) {
fprintf(f, "\tmovl %d(%%esp), %%%s\n",
(i + sarg_ofs) * 4, pp->arg[i].reg);
+ if (pp->arg[i].type.is_retreg)
+ fprintf(f, "\tmovl (%%%s), %%%s\n",
+ pp->arg[i].reg, pp->arg[i].reg);
}
}
fprintf(f, "\n\t# %s\n", pp->is_stdcall ? "__stdcall" : "__cdecl");
- fprintf(f, "\tcall %s\n\n", sym);
+ fprintf(f, "\tcall %s\n\n", sym_out);
- if (args_repushed && !pp->is_stdcall)
+ if (args_repushed && !pp->is_stdcall) {
fprintf(f, "\tadd $%d,%%esp\n", args_repushed * 4);
+ sarg_ofs -= args_repushed;
+ }
- // restore regs
- for (i = pp->argc - 1; i >= 0; i--) {
- if (pp->arg[i].reg != NULL && is_x86_reg_saved(pp->arg[i].reg))
- fprintf(f, "\tpopl %%%s\n", pp->arg[i].reg);
+ // update the retreg regs
+ if (pp->has_retreg) {
+ for (i = 0; i < pp->argc; i++) {
+ if (pp->arg[i].type.is_retreg) {
+ fprintf(f, "\tmovl %d(%%esp), %%ecx\n"
+ "\tmovl %%%s, (%%ecx)\n",
+ (i + sarg_ofs) * 4, pp->arg[i].reg);
+ }
+ }
}
+ // restore regs
+ for (i = ARRAY_SIZE(c_save_regs) - 1; i >= 0; i--)
+ fprintf(f, "\tpopl %%%s\n", c_save_regs[i]);
+
fprintf(f, "\tret\n\n");
}
-static void out_fromasm_x86(FILE *f, char *sym, struct parsed_proto *pp)
+static void out_fromasm_x86(FILE *f, const char *sym,
+ const struct parsed_proto *pp)
{
+ int reg_ofs[ARRAY_SIZE(pp->arg)];
int sarg_ofs = 1; // stack offset to args, in DWORDs
+ int saved_regs = 0;
+ int ecx_ofs = -1;
+ int edx_ofs = -1;
+ int c_is_stdcall;
+ int argc_repush;
int stack_args;
+ int ret64;
int i;
- fprintf(f, "# %s\n", pp->is_stdcall ? "__stdcall" : "__cdecl");
- fprintf(f, ".global %s\n", sym);
+ argc_repush = pp->argc;
+ stack_args = pp->argc_stack;
+ if (pp->is_vararg) {
+ argc_repush = ARRAY_SIZE(pp->arg); // hopefully enough?
+ stack_args = argc_repush - pp->argc_reg;
+ }
+
+ ret64 = strstr(pp->ret_type.name, "int64") != NULL;
+
+ fprintf(f, "# %s",
+ pp->is_fastcall ? "__fastcall" :
+ (pp->is_stdcall ? "__stdcall" : "__cdecl"));
+ if (ret64)
+ fprintf(f, " ret64");
+ fprintf(f, "\n.global %s\n", sym);
fprintf(f, "%s:\n", sym);
- if (pp->argc_reg == 0 && !pp->is_stdcall) {
- fprintf(f, "\tjmp _%s\n\n", sym);
+ if ((pp->argc_reg == 0 || pp->is_fastcall)
+ && !IS(pp->name, "storm_491")) // wants edx save :(
+ {
+ fprintf(f, "\tjmp %s\n\n", pp_to_name(pp));
return;
}
- fprintf(f, "\tpushl %%edx\n"); // just in case..
+ c_is_stdcall = (pp->argc_reg == 0 && pp->is_stdcall);
+
+ // at least sc sub_47B150 needs edx to be preserved
+ // int64 returns use edx:eax - no edx save
+ // we use ecx also as scratch
+ fprintf(f, "\tpushl %%ecx\n");
+ saved_regs++;
sarg_ofs++;
+ ecx_ofs = sarg_ofs;
+ if (!ret64) {
+ fprintf(f, "\tpushl %%edx\n");
+ saved_regs++;
+ sarg_ofs++;
+ edx_ofs = sarg_ofs;
+ }
+
+ // need space for retreg args
+ if (pp->has_retreg) {
+ for (i = 0; i < pp->argc; i++) {
+ if (!pp->arg[i].type.is_retreg)
+ continue;
+ if (IS(pp->arg[i].reg, "ecx") && ecx_ofs >= 0) {
+ reg_ofs[i] = ecx_ofs;
+ continue;
+ }
+ if (IS(pp->arg[i].reg, "edx") && edx_ofs >= 0) {
+ reg_ofs[i] = edx_ofs;
+ continue;
+ }
+ fprintf(f, "\tpushl %%%s\n", pp->arg[i].reg);
+ saved_regs++;
+ sarg_ofs++;
+ reg_ofs[i] = sarg_ofs;
+ }
+ }
// construct arg stack
- stack_args = pp->argc_stack;
- for (i = pp->argc - 1; i >= 0; i--) {
+ for (i = argc_repush - 1; i >= 0; i--) {
if (pp->arg[i].reg == NULL) {
- fprintf(f, "\tmovl %d(%%esp), %%edx\n",
+ fprintf(f, "\tmovl %d(%%esp), %%ecx\n",
(sarg_ofs + stack_args - 1) * 4);
- fprintf(f, "\tpushl %%edx\n");
+ fprintf(f, "\tpushl %%ecx\n");
stack_args--;
}
else {
- fprintf(f, "\tpushl %%%s\n", pp->arg[i].reg);
+ const char *reg = pp->arg[i].reg;
+ if (pp->arg[i].type.is_retreg) {
+ reg = "ecx";
+ fprintf(f, "\tlea %d(%%esp), %%ecx\n",
+ (sarg_ofs - reg_ofs[i]) * 4);
+ }
+ else if (IS(reg, "ecx"))
+ // must reload original ecx
+ fprintf(f, "\tmovl %d(%%esp), %%ecx\n",
+ (sarg_ofs - 2) * 4);
+
+ fprintf(f, "\tpushl %%%s\n", reg);
}
sarg_ofs++;
}
- // no worries about calling conventions - always __cdecl
- fprintf(f, "\n\tcall _%s\n\n", sym);
-
- if (sarg_ofs > 2)
- fprintf(f, "\tadd $%d,%%esp\n", (sarg_ofs - 2) * 4);
+ fprintf(f, "\n\tcall %s\n\n", pp_to_name(pp));
+
+ if (!c_is_stdcall && sarg_ofs > saved_regs + 1)
+ fprintf(f, "\tadd $%d,%%esp\n",
+ (sarg_ofs - (saved_regs + 1)) * 4);
+
+ // pop retregs
+ if (pp->has_retreg) {
+ for (i = pp->argc - 1; i >= 0; i--) {
+ if (!pp->arg[i].type.is_retreg)
+ continue;
+ if (IS(pp->arg[i].reg, "ecx") && ecx_ofs >= 0) {
+ continue;
+ }
+ if (IS(pp->arg[i].reg, "edx") && edx_ofs >= 0) {
+ continue;
+ }
+ fprintf(f, "\tpopl %%%s\n", pp->arg[i].reg);
+ }
+ }
- fprintf(f, "\tpopl %%edx\n");
+ if (!ret64)
+ fprintf(f, "\tpopl %%edx\n");
+ fprintf(f, "\tpopl %%ecx\n");
if (pp->is_stdcall && pp->argc_stack)
fprintf(f, "\tret $%d\n\n", pp->argc_stack * 4);
int main(int argc, char *argv[])
{
FILE *fout, *fsyms_to, *fsyms_from, *fhdr;
- struct parsed_proto pp;
+ const struct parsed_proto *pp;
char line[256];
+ char sym_noat[256];
char sym[256];
- int ret;
+ char *p;
+ int ret = 1;
if (argc != 5) {
printf("usage:\n%s <bridge.s> <toasm_symf> <fromasm_symf> <hdrf>\n",
if (sym[0] == 0 || sym[0] == ';' || sym[0] == '#')
continue;
- ret = proto_parse(fhdr, sym, &pp);
- if (ret)
+ // IDA asm doesn't do '@' notation..
+ strcpy(sym_noat, sym);
+ p = strchr(sym_noat, '@');
+ if (p != NULL)
+ *p = 0;
+
+ pp = proto_parse(fhdr, sym_noat, 0);
+ if (pp == NULL)
goto out;
- out_toasm_x86(fout, sym, &pp);
- proto_release(&pp);
+ out_toasm_x86(fout, sym_noat, pp);
}
fprintf(fout, "# from asm\n\n");
if (sym[0] == 0 || sym[0] == ';' || sym[0] == '#')
continue;
- ret = proto_parse(fhdr, sym, &pp);
- if (ret)
+ pp = proto_parse(fhdr, sym, 0);
+ if (pp == NULL)
goto out;
- out_fromasm_x86(fout, sym, &pp);
- proto_release(&pp);
+ out_fromasm_x86(fout, sym, pp);
}
ret = 0;