cmpmrg_text: detect some refs to rm'd funcs

diff --git a/tools/cmpmrg_text.c b/tools/cmpmrg_text.c
index 62a9f6d..5a0d296 100644 (file)
--- a/tools/cmpmrg_text.c
+++ b/tools/cmpmrg_text.c
@@ -68,7 +68,8 @@ typedef struct {
 
 struct my_symtab {
   unsigned int addr;
-  unsigned int fpos; // for patching
+  //unsigned int fpos; // for patching
+  unsigned int is_text:1;
   char *name;
 };
 
@@ -90,9 +91,11 @@ static int symt_cmp(const void *p1_, const void *p2_)
 
 void parse_headers(FILE *f, unsigned int *base_out,
        struct my_sect_info *sect_i,
-       struct my_symtab **symtab_out, long *sym_cnt)
+       struct my_symtab **symtab_out, long *sym_cnt,
+       struct my_symtab **raw_symtab_out, long *raw_sym_cnt)
 {
-       struct my_symtab *symt_o = NULL;
+       struct my_symtab *symt_txt = NULL;
+       struct my_symtab *symt_all = NULL;
        char *stringtab = NULL;
        unsigned int base = 0;
        int text_scnum = 0;
@@ -218,8 +221,10 @@ void parse_headers(FILE *f, unsigned int *base_out,
        if (hdr.f_nsyms != 0) {
                symname[8] = 0;
 
-               symt_o = malloc(hdr.f_nsyms * sizeof(symt_o[0]) + 1);
-               my_assert_not(symt_o, NULL);
+               symt_txt = malloc(hdr.f_nsyms * sizeof(symt_txt[0]) + 1);
+               my_assert_not(symt_txt, NULL);
+               symt_all = malloc(hdr.f_nsyms * sizeof(symt_all[0]) + 1);
+               my_assert_not(symt_all, NULL);
 
                ret = fseek(f, hdr.f_symptr
                                + hdr.f_nsyms * sizeof(syment), SEEK_SET);
@@ -239,7 +244,7 @@ void parse_headers(FILE *f, unsigned int *base_out,
        }
 
        for (i = s = 0; i < hdr.f_nsyms; i++) {
-               long pos = ftell(f);
+               //long pos = ftell(f);
 
                ret = fread(&syment, 1, sizeof(syment), f);
                my_assert(ret, sizeof(syment));
@@ -248,16 +253,18 @@ void parse_headers(FILE *f, unsigned int *base_out,
                //printf("%3d %2d %08x '%s'\n", syment.e_sclass,
                //      syment.e_scnum, syment.e_value, symname);
 
-               if (syment.e_scnum != text_scnum || syment.e_sclass != C_EXT)
-                       continue;
-
-               symt_o[s].addr = syment.e_value;
-               symt_o[s].fpos = pos;
+               symt_all[i].addr = syment.e_value;
+               //symt_all[i].fpos = pos;
                if (syment.e.e.e_zeroes == 0)
-                       symt_o[s].name = stringtab + syment.e.e.e_offset;
+                       symt_all[i].name = stringtab + syment.e.e.e_offset;
                else
-                       symt_o[s].name = strdup(symname);
-               s++;
+                       symt_all[i].name = strdup(symname);
+
+               symt_all[i].is_text = (syment.e_scnum == text_scnum);
+               if (symt_all[i].is_text && syment.e_sclass == C_EXT) {
+                       symt_txt[s] = symt_all[i];
+                       s++;
+               }
 
                if (syment.e_numaux) {
                        ret = fseek(f, syment.e_numaux * sizeof(syment),
@@ -267,11 +274,13 @@ void parse_headers(FILE *f, unsigned int *base_out,
                }
        }
 
-       if (symt_o != NULL)
-               qsort(symt_o, s, sizeof(symt_o[0]), symt_cmp);
+       if (symt_txt != NULL)
+               qsort(symt_txt, s, sizeof(symt_txt[0]), symt_cmp);
 
        *sym_cnt = s;
-       *symtab_out = symt_o;
+       *symtab_out = symt_txt;
+       *raw_sym_cnt = i;
+       *raw_symtab_out = symt_all;
 }
 
 static int handle_pad(uint8_t *d_obj, uint8_t *d_exe, int maxlen)
@@ -457,7 +466,7 @@ static int check_equiv(uint8_t *d_obj, uint8_t *d_exe, int maxlen)
 static void fill_int3(unsigned char *d, int len)
 {
        while (len-- > 0) {
-               if (*d == 0xcc)
+               if (d[0] == 0xcc && d[1] == 0xcc)
                        break;
                *d++ = 0xcc;
        }
@@ -465,11 +474,12 @@ static void fill_int3(unsigned char *d, int len)
 
 int main(int argc, char *argv[])
 {
+       unsigned int base = 0, addr, addr2, end, sym, *t;
        struct my_sect_info s_text_obj, s_text_exe;
+       struct my_symtab *raw_syms_obj = NULL;
        struct my_symtab *syms_obj = NULL;
-       long sym_cnt_obj;
+       long sym_cnt_obj, raw_sym_cnt_obj;
        FILE *f_obj, *f_exe;
-       unsigned int base = 0, addr, end;
        SCNHDR tmphdr;
        long sztext_cmn;
        int retval = 1;
@@ -496,8 +506,9 @@ int main(int argc, char *argv[])
                return 1;
        }
 
-       parse_headers(f_obj, NULL, &s_text_obj, &syms_obj, &sym_cnt_obj);
-       parse_headers(f_exe, &base, &s_text_exe, NULL, NULL);
+       parse_headers(f_obj, NULL, &s_text_obj, &syms_obj, &sym_cnt_obj,
+                     &raw_syms_obj, &raw_sym_cnt_obj);
+       parse_headers(f_exe, &base, &s_text_exe, NULL, NULL, NULL, NULL);
 
        sztext_cmn = s_text_obj.size;
        if (sztext_cmn > s_text_exe.size)
@@ -571,11 +582,25 @@ int main(int argc, char *argv[])
        // remove relocs
        for (i = 0; i < s_text_obj.reloc_cnt; i++) {
                addr = s_text_obj.relocs[i].r_vaddr;
+               sym = s_text_obj.relocs[i].r_symndx;
                if (addr > s_text_obj.size - 4) {
                        printf("reloc addr OOR: %x\n", addr);
                        goto out;
                }
-               if (*(unsigned int *)(s_text_obj.data + addr) == 0xcccccccc) {
+               if (sym >= raw_sym_cnt_obj) {
+                       printf("reloc sym OOR: %d/%ld\n",
+                               sym, raw_sym_cnt_obj);
+                       goto out;
+               }
+#if 0
+               printf("r %08x -> %08x %s\n", base + addr,
+                       raw_syms_obj[sym].addr,
+                       raw_syms_obj[sym].name);
+#endif
+               t = (unsigned int *)(s_text_obj.data + addr);
+               if (t[0] == 0xcccccccc
+                || t[-1] == 0xcccccccc) { // jumptab of a func?
+                       t[0] = 0xcccccccc;
                        memmove(&s_text_obj.relocs[i],
                                &s_text_obj.relocs[i + 1],
                                (s_text_obj.reloc_cnt - i - 1)
@@ -583,6 +608,17 @@ int main(int argc, char *argv[])
                        i--;
                        s_text_obj.reloc_cnt--;
                }
+               // note: branches/calls already linked,
+               // so only useful for dd refs
+               else if (raw_syms_obj[sym].is_text) {
+                       addr2 = raw_syms_obj[sym].addr;
+                       if (s_text_obj.data[addr2] == 0xcc) {
+                               printf("warning: reloc %08x -> %08x "
+                                       "points to rm'd target '%s'\n",
+                                       base + addr, base + addr2,
+                                       raw_syms_obj[sym].name);
+                       }
+               }
        }
 
        // patch .text