#ifdef TARGET_DEFS_ONLY #define EM_TCC_TARGET EM_X86_64 /* relocation type for 32 bit data relocation */ #define R_DATA_32 R_X86_64_32S #define R_DATA_PTR R_X86_64_64 #define R_JMP_SLOT R_X86_64_JUMP_SLOT #define R_GLOB_DAT R_X86_64_GLOB_DAT #define R_COPY R_X86_64_COPY #define R_RELATIVE R_X86_64_RELATIVE #define R_NUM R_X86_64_NUM #define ELF_START_ADDR 0x400000 #define ELF_PAGE_SIZE 0x200000 #define PCRELATIVE_DLLPLT 1 #define RELOCATE_DLLPLT 1 #else /* !TARGET_DEFS_ONLY */ #include "tcc.h" /* Returns 1 for a code relocation, 0 for a data relocation. For unknown relocations, returns -1. */ int code_reloc (int reloc_type) { switch (reloc_type) { case R_X86_64_32: case R_X86_64_32S: case R_X86_64_64: case R_X86_64_GOTPC32: case R_X86_64_GOTPC64: case R_X86_64_GOTPCREL: case R_X86_64_GOTPCRELX: case R_X86_64_REX_GOTPCRELX: case R_X86_64_GOTTPOFF: case R_X86_64_GOT32: case R_X86_64_GOT64: case R_X86_64_GLOB_DAT: case R_X86_64_COPY: case R_X86_64_RELATIVE: case R_X86_64_GOTOFF64: return 0; case R_X86_64_PC32: case R_X86_64_PC64: case R_X86_64_PLT32: case R_X86_64_PLTOFF64: case R_X86_64_JUMP_SLOT: return 1; } tcc_error ("Unknown relocation type: %d", reloc_type); return -1; } /* Returns an enumerator to describe whether and when the relocation needs a GOT and/or PLT entry to be created. See tcc.h for a description of the different values. */ int gotplt_entry_type (int reloc_type) { switch (reloc_type) { case R_X86_64_GLOB_DAT: case R_X86_64_JUMP_SLOT: case R_X86_64_COPY: case R_X86_64_RELATIVE: return NO_GOTPLT_ENTRY; /* The following relocs wouldn't normally need GOT or PLT slots, but we need them for simplicity in the link editor part. See our caller for comments. */ case R_X86_64_32: case R_X86_64_32S: case R_X86_64_64: case R_X86_64_PC32: case R_X86_64_PC64: return AUTO_GOTPLT_ENTRY; case R_X86_64_GOTTPOFF: return BUILD_GOT_ONLY; case R_X86_64_GOT32: case R_X86_64_GOT64: case R_X86_64_GOTPC32: case R_X86_64_GOTPC64: case R_X86_64_GOTOFF64: case R_X86_64_GOTPCREL: case R_X86_64_GOTPCRELX: case R_X86_64_REX_GOTPCRELX: case R_X86_64_PLT32: case R_X86_64_PLTOFF64: return ALWAYS_GOTPLT_ENTRY; } tcc_error ("Unknown relocation type: %d", reloc_type); return -1; } ST_FUNC unsigned create_plt_entry(TCCState *s1, unsigned got_offset, struct sym_attr *attr) { Section *plt = s1->plt; uint8_t *p; int modrm; unsigned plt_offset, relofs; modrm = 0x25; /* empty PLT: create PLT0 entry that pushes the library identifier (GOT + PTR_SIZE) and jumps to ld.so resolution routine (GOT + 2 * PTR_SIZE) */ if (plt->data_offset == 0) { p = section_ptr_add(plt, 16); p[0] = 0xff; /* pushl got + PTR_SIZE */ p[1] = modrm + 0x10; write32le(p + 2, PTR_SIZE); p[6] = 0xff; /* jmp *(got + PTR_SIZE * 2) */ p[7] = modrm; write32le(p + 8, PTR_SIZE * 2); } plt_offset = plt->data_offset; /* The PLT slot refers to the relocation entry it needs via offset. The reloc entry is created below, so its offset is the current data_offset */ relofs = s1->got->reloc ? s1->got->reloc->data_offset : 0; /* Jump to GOT entry where ld.so initially put the address of ip + 4 */ p = section_ptr_add(plt, 16); p[0] = 0xff; /* jmp *(got + x) */ p[1] = modrm; write32le(p + 2, got_offset); p[6] = 0x68; /* push $xxx */ /* On x86-64, the relocation is referred to by _index_ */ write32le(p + 7, relofs / sizeof (ElfW_Rel)); p[11] = 0xe9; /* jmp plt_start */ write32le(p + 12, -(plt->data_offset)); return plt_offset; } /* relocate the PLT: compute addresses and offsets in the PLT now that final address for PLT and GOT are known (see fill_program_header) */ 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) { int x = s1->got->sh_addr - s1->plt->sh_addr - 6; add32le(p + 2, x); add32le(p + 8, x - 6); p += 16; while (p < p_end) { add32le(p + 2, x + s1->plt->data - p); p += 16; } } } static ElfW_Rel *qrel; /* ptr to next reloc entry reused */ void relocate_init(Section *sr) { qrel = (ElfW_Rel *) sr->data; } void relocate(TCCState *s1, ElfW_Rel *rel, int type, unsigned char *ptr, addr_t addr, addr_t val) { int sym_index, esym_index; sym_index = ELFW(R_SYM)(rel->r_info); switch (type) { case R_X86_64_64: if (s1->output_type == TCC_OUTPUT_DLL) { esym_index = s1->sym_attrs[sym_index].dyn_index; qrel->r_offset = rel->r_offset; if (esym_index) { qrel->r_info = ELFW(R_INFO)(esym_index, R_X86_64_64); qrel->r_addend = rel->r_addend; qrel++; break; } else { qrel->r_info = ELFW(R_INFO)(0, R_X86_64_RELATIVE); qrel->r_addend = read64le(ptr) + val; qrel++; } } add64le(ptr, val); break; case R_X86_64_32: case R_X86_64_32S: if (s1->output_type == TCC_OUTPUT_DLL) { /* XXX: this logic may depend on TCC's codegen now TCC uses R_X86_64_32 even for a 64bit pointer */ qrel->r_info = ELFW(R_INFO)(0, R_X86_64_RELATIVE); /* Use sign extension! */ qrel->r_addend = (int)read32le(ptr) + val; qrel++; } add32le(ptr, val); break; case R_X86_64_PC32: if (s1->output_type == TCC_OUTPUT_DLL) { /* DLL relocation */ esym_index = s1->sym_attrs[sym_index].dyn_index; if (esym_index) { qrel->r_offset = rel->r_offset; qrel->r_info = ELFW(R_INFO)(esym_index, R_X86_64_PC32); /* Use sign extension! */ qrel->r_addend = (int)read32le(ptr) + rel->r_addend; qrel++; break; } } goto plt32pc32; case R_X86_64_PLT32: /* fallthrough: val already holds the PLT slot address */ plt32pc32: { long long diff; diff = (long long)val - addr; if (diff < -2147483648LL || diff > 2147483647LL) { tcc_error("internal error: relocation failed"); } add32le(ptr, diff); } break; case R_X86_64_PLTOFF64: add64le(ptr, val - s1->got->sh_addr + rel->r_addend); break; case R_X86_64_PC64: if (s1->output_type == TCC_OUTPUT_DLL) { /* DLL relocation */ esym_index = s1->sym_attrs[sym_index].dyn_index; if (esym_index) { qrel->r_offset = rel->r_offset; qrel->r_info = ELFW(R_INFO)(esym_index, R_X86_64_PC64); qrel->r_addend = read64le(ptr) + rel->r_addend; qrel++; break; } } add64le(ptr, val - addr); break; case R_X86_64_GLOB_DAT: case R_X86_64_JUMP_SLOT: /* They don't need addend */ write64le(ptr, val - rel->r_addend); break; case R_X86_64_GOTPCREL: case R_X86_64_GOTPCRELX: case R_X86_64_REX_GOTPCRELX: add32le(ptr, s1->got->sh_addr - addr + s1->sym_attrs[sym_index].got_offset - 4); break; case R_X86_64_GOTPC32: add32le(ptr, s1->got->sh_addr - addr + rel->r_addend); break; case R_X86_64_GOTPC64: add64le(ptr, s1->got->sh_addr - addr + rel->r_addend); break; case R_X86_64_GOTTPOFF: add32le(ptr, val - s1->got->sh_addr); break; case R_X86_64_GOT32: /* we load the got offset */ add32le(ptr, s1->sym_attrs[sym_index].got_offset); break; case R_X86_64_GOT64: /* we load the got offset */ add64le(ptr, s1->sym_attrs[sym_index].got_offset); break; case R_X86_64_GOTOFF64: add64le(ptr, val - s1->got->sh_addr); break; case R_X86_64_RELATIVE: #ifdef TCC_TARGET_PE add32le(ptr, val - s1->pe_imagebase); #endif /* do nothing */ break; } } #endif /* !TARGET_DEFS_ONLY */