aarch64: Fix -run.

This adds some more support for properly transfering some
offsets over the different stages of a relocations life.
Still not at all psABI compliant and DSOs can't yet be generated.
But it runs the testsuite in qemu-arm64.

tccelf.c

@@ -451,7 +451,7 @@ ST_FUNC void relocate_syms(TCCState *s1, int do_resolve)
                 if (addr) {
                     sym->st_value = (addr_t)addr;
 #ifdef DEBUG_RELOC
-		    printf ("relocate_sym: %s -> 0x%x\n", name, sym->st_value);
+		    printf ("relocate_sym: %s -> 0x%lx\n", name, sym->st_value);
 #endif
                     goto found;
                 }
@@ -797,8 +797,21 @@ ST_FUNC void relocate_section(TCCState *s1, Section *s)
             break;
         case R_AARCH64_JUMP26:
         case R_AARCH64_CALL26:
+	    /* This check must match the one in build_got_entries, testing
+	       if we really need a PLT slot.  */
+	    if (sym->st_shndx == SHN_UNDEF)
+	        /* 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).  */
+		val = s1->plt->sh_addr + rel->r_addend;
+#ifdef DEBUG_RELOC
+	    printf ("reloc %d @ 0x%lx: val=0x%lx name=%s\n", type, addr, val,
+		    (char *) symtab_section->link->data + sym->st_name);
+#endif
             if (((val - addr) + ((uint64_t)1 << 27)) & ~(uint64_t)0xffffffc)
-                tcc_error("R_AARCH64_(JUMP|CALL)26 relocation failed");
+	      {
+                tcc_error("R_AARCH64_(JUMP|CALL)26 relocation failed (val=%lx, addr=%lx)", addr, val);
+	      }
             *(uint32_t *)ptr = 0x14000000 | (type == R_AARCH64_CALL26) << 31 |
                 ((val - addr) >> 2 & 0x3ffffff);
             break;
@@ -818,7 +831,17 @@ ST_FUNC void relocate_section(TCCState *s1, Section *s)
                  & 0xff8) << 7;
             break;
         case R_AARCH64_COPY:
-          break;
+            break;
+        case R_AARCH64_GLOB_DAT:
+        case R_AARCH64_JUMP_SLOT:
+            /* They don't need addend */
+#ifdef DEBUG_RELOC
+	    printf ("reloc %d @ 0x%lx: val=0x%lx name=%s\n", type, addr,
+		    val - rel->r_addend,
+		    (char *) symtab_section->link->data + sym->st_name);
+#endif
+            *(addr_t *)ptr = val - rel->r_addend;
+            break;
         default:
             fprintf(stderr, "FIXME: handle reloc type %x at %x [%p] to %x\n",
                     type, (unsigned)addr, ptr, (unsigned)val);
@@ -1211,6 +1234,7 @@ static unsigned long put_got_entry(TCCState *s1,
             plt = s1->plt;
             if (plt->data_offset == 0)
                 section_ptr_add(plt, 32);
+            symattr->plt_offset = plt->data_offset;
             p = section_ptr_add(plt, 16);
             put32(p, s1->got->data_offset);
             put32(p + 4, (uint64_t)s1->got->data_offset >> 32);
@@ -1372,6 +1396,23 @@ ST_FUNC void build_got_entries(TCCState *s1)
                 put_got_entry(s1, reloc_type, sym->st_size, sym->st_info,
                               sym_index);
                 break;
+
+	    case R_AARCH64_JUMP26:
+	    case R_AARCH64_CALL26:
+                if (!s1->got)
+                    build_got(s1);
+                sym_index = ELFW(R_SYM)(rel->r_info);
+                sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
+                if (sym->st_shndx == SHN_UNDEF) {
+		    unsigned long ofs;
+		    reloc_type = R_AARCH64_JUMP_SLOT;
+                    ofs = put_got_entry(s1, reloc_type, sym->st_size,
+					sym->st_info, sym_index);
+		    /* We store the place of the generated PLT slot
+		       in our addend.  */
+		    rel->r_addend += ofs;
+                }
+		break;
 #elif defined(TCC_TARGET_C67)
             case R_C60_GOT32:
             case R_C60_GOTOFF:
@@ -1895,8 +1936,8 @@ ST_FUNC void relocate_plt(TCCState *s1)
         uint64_t plt = s1->plt->sh_addr;
         uint64_t got = s1->got->sh_addr;
         uint64_t off = (got >> 12) - (plt >> 12);
-        if ((off + ((uint64_t)1 << 20)) >> 21)
+        if ((off + ((uint32_t)1 << 20)) >> 21)
-            tcc_error("Failed relocating PLT");
+            tcc_error("Failed relocating PLT (off=0x%lx, got=0x%lx, plt=0x%lx)", off, got, plt);
         put32(p, 0xa9bf7bf0); // stp x16,x30,[sp,#-16]!
         put32(p + 4, (0x90000010 | // adrp x16,...
                       (off & 0x1ffffc) << 3 | (off & 3) << 29));
@@ -1914,8 +1955,8 @@ ST_FUNC void relocate_plt(TCCState *s1)
             uint64_t addr = got +
                 (get32(p) | (uint64_t)get32(p + 4) << 32);
             uint32_t off = (addr >> 12) - (pc >> 12);
-            if ((off + ((uint64_t)1 << 20)) >> 21)
+            if ((off + ((uint32_t)1 << 20)) >> 21)
-                tcc_error("Failed relocating PLT");
+                tcc_error("Failed relocating PLT (off=0x%lx, addr=0x%lx, pc=0x%lx)", off, addr, pc);
             put32(p, (0x90000010 | // adrp x16,...
                       (off & 0x1ffffc) << 3 | (off & 3) << 29));
             put32(p + 4, (0xf9400211 | // ldr x17,[x16,#...]
@@ -2590,9 +2631,12 @@ static int elf_output_file(TCCState *s1, const char *filename)
 
             /* relocate symbols in .dynsym now that final addresses are known */
             for_each_elem(s1->dynsym, 1, sym, ElfW(Sym)) {
-                /* relocate to PLT if symbol corresponds to a PLT entry */
                 if (sym->st_shndx == SHN_UNDEF) {
-                    if (sym->st_value)
+                    /* relocate to PLT if symbol corresponds to a PLT entry,
+		       but not if it's a weak symbol */
+		    if (ELFW(ST_BIND)(sym->st_info) == STB_WEAK)
+		        sym->st_value = 0;
+		    else if (sym->st_value)
                         sym->st_value += s1->plt->sh_addr;
                 } else if (sym->st_shndx < SHN_LORESERVE) {
                     /* do symbol relocation */

tccrun.c

@@ -196,7 +196,7 @@ static int tcc_relocate_ex(TCCState *s1, void *ptr)
         if (0 == (s->sh_flags & SHF_ALLOC))
             continue;
         length = s->data_offset;
-        // printf("%-12s %08x %04x\n", s->name, s->sh_addr, length);
+        // printf("%-12s %08lx %04x\n", s->name, s->sh_addr, length);
         ptr = (void*)s->sh_addr;
         if (NULL == s->data || s->sh_type == SHT_NOBITS)
             memset(ptr, 0, length);