x86_64: Create proper PLT and GOT also for -run

This makes us use the normal PLT/GOT codepaths also for -run, which formerly used an on-the-side blob for the jump tables. For x86_64 only for now, arm coming up.

Michael Matz committed 12 years ago

Commit 9750d0b1 parent c4427743 files · +24 −17Browse files

Unified · Split

3 files

tcc.h +2 −1
tccelf.c +21 −16
tccrun.c +1 −0

tcc.h+2−1

     void *write_mem;
     unsigned long mem_size;
 # endif
-# if !defined TCC_TARGET_PE && (defined TCC_TARGET_X86_64 || defined TCC_TARGET_ARM)
+# if !defined TCC_TARGET_PE && (defined TCC_TARGET_ARM)
     /* write PLT and GOT here */
     char *runtime_plt_and_got;
     unsigned runtime_plt_and_got_offset;
 ST_FUNC void relocate_common_syms(void);
 ST_FUNC void relocate_syms(TCCState *s1, int do_resolve);
 ST_FUNC void relocate_section(TCCState *s1, Section *s);
+ST_FUNC void relocate_plt(TCCState *s1);
 ST_FUNC void tcc_add_linker_symbols(TCCState *s1);
 ST_FUNC int tcc_load_object_file(TCCState *s1, int fd, unsigned long file_offset);

tccelf.c+21−16

 	    /* We've put the PLT slot offset into r_addend when generating
 	       it, and that's what we must use as relocation value (adjusted
 	       by section offset of course).  */
-	    if (s1->output_type != TCC_OUTPUT_MEMORY)
+	    val = s1->plt->sh_addr + rel->r_addend;
-	        val = s1->plt->sh_addr + rel->r_addend;
 	    /* fallthrough.  */
 	plt32pc32:
         case R_X86_64_GLOB_DAT:
         case R_X86_64_JUMP_SLOT:
             /* They don't need addend */
-            *(int *)ptr = val - rel->r_addend;
+            *(addr_t *)ptr = val - rel->r_addend;
             break;
         case R_X86_64_GOTPCREL:
 #ifdef TCC_HAS_RUNTIME_PLTGOT
     if (!s1->got)
         build_got(s1);
-    need_plt_entry = s1->dynsym &&
+    need_plt_entry =
 #ifdef TCC_TARGET_X86_64
         (reloc_type == R_X86_64_JUMP_SLOT);
 #elif defined(TCC_TARGET_I386)
         0;
 #endif
+    if (need_plt_entry && !s1->plt) {
+	/* add PLT */
+	s1->plt = new_section(s1, ".plt", SHT_PROGBITS,
+			      SHF_ALLOC | SHF_EXECINSTR);
+	s1->plt->sh_entsize = 4;
+    }
     /* If a got/plt entry already exists for that symbol, no need to add one */
     if (sym_index < s1->nb_sym_attrs) {
 	if (need_plt_entry && s1->sym_attrs[sym_index].plt_offset)
     if (!need_plt_entry)
         symattr->got_offset = s1->got->data_offset;
-    if (s1->dynsym) {
+    sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
-        sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
+    name = (char *) symtab_section->link->data + sym->st_name;
-        name = (char *) symtab_section->link->data + sym->st_name;
+    offset = sym->st_value;
-        offset = sym->st_value;
 #if defined(TCC_TARGET_I386) || defined(TCC_TARGET_X86_64)
         if (need_plt_entry) {
             Section *plt;
                 offset = plt->data_offset - 16;
         }
 #elif defined(TCC_TARGET_C67)
+    if (s1->dynsym) {
         tcc_error("C67 got not implemented");
+    }
 #else
 #error unsupported CPU
 #endif
+    if (s1->dynsym) {
 	/* XXX This might generate multiple syms for name.  */
         index = put_elf_sym(s1->dynsym, offset,
                             size, info, 0, sym->st_shndx, name);
                         reloc_type = R_X86_64_JUMP_SLOT;
                     ofs = put_got_entry(s1, reloc_type, sym->st_size,
 					sym->st_info, sym_index);
-		    if (type == R_X86_64_PLT32
+		    if (type == R_X86_64_PLT32)
-			&& s1->output_type != TCC_OUTPUT_MEMORY)
 		        /* We store the place of the generated PLT slot
 			   in our addend.  */
 		        rel->r_addend += ofs;
 /* relocate the PLT: compute addresses and offsets in the PLT now that final
    address for PLT and GOT are known (see fill_program_header) */
-static void relocate_plt(TCCState *s1)
+ST_FUNC void relocate_plt(TCCState *s1)
 {
     uint8_t *p, *p_end;
+    if (!s1->plt)
+      return;
     p = s1->plt->data;
     p_end = p + s1->plt->data_offset;
     if (p < p_end) {
             dynamic->link = dynstr;
             dynamic->sh_entsize = sizeof(ElfW(Dyn));
-            /* add PLT */
-            s1->plt = new_section(s1, ".plt", SHT_PROGBITS,
-                                  SHF_ALLOC | SHF_EXECINSTR);
-            s1->plt->sh_entsize = 4;
             build_got(s1);
             if (file_type == TCC_OUTPUT_EXE) {

tccrun.c+1−0

@@ -197,6 +197,7 @@ static int tcc_relocate_ex(TCCState s1, void ptr) · 196 unmodified lines
197	if (s->reloc)	197	if (s->reloc)
198	relocate_section(s1, s);	198	relocate_section(s1, s);
199	}	199	}
		200	relocate_plt(s1);
200		201
201	for(i = 1; i < s1->nb_sections; i++) {	202	for(i = 1; i < s1->nb_sections; i++) {
202	s = s1->sections[i];	203	s = s1->sections[i];

x86_64: Create proper PLT and GOT also for -run

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