#ifdef TARGET_DEFS_ONLY #define EM_TCC_TARGET EM_RISCV #define R_DATA_32 R_RISCV_32 #define R_DATA_PTR R_RISCV_64 #define R_JMP_SLOT R_RISCV_JUMP_SLOT #define R_GLOB_DAT R_RISCV_64 #define R_COPY R_RISCV_COPY #define R_RELATIVE R_RISCV_RELATIVE #define R_NUM R_RISCV_NUM #define ELF_START_ADDR 0x00010000 #define ELF_PAGE_SIZE 0x1000 #define PCRELATIVE_DLLPLT 1 #define RELOCATE_DLLPLT 1 #else /* !TARGET_DEFS_ONLY */ //#define DEBUG_RELOC #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_RISCV_BRANCH: case R_RISCV_CALL: case R_RISCV_JAL: return 1; case R_RISCV_GOT_HI20: case R_RISCV_PCREL_HI20: case R_RISCV_PCREL_LO12_I: case R_RISCV_PCREL_LO12_S: case R_RISCV_32_PCREL: case R_RISCV_SET6: case R_RISCV_SUB6: case R_RISCV_ADD16: case R_RISCV_ADD32: case R_RISCV_ADD64: case R_RISCV_SUB16: case R_RISCV_SUB32: case R_RISCV_SUB64: case R_RISCV_32: case R_RISCV_64: return 0; case R_RISCV_CALL_PLT: return 1; } 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_RISCV_ALIGN: case R_RISCV_RELAX: case R_RISCV_RVC_BRANCH: case R_RISCV_RVC_JUMP: case R_RISCV_JUMP_SLOT: case R_RISCV_SET6: case R_RISCV_SUB6: case R_RISCV_ADD16: case R_RISCV_SUB16: return NO_GOTPLT_ENTRY; case R_RISCV_BRANCH: case R_RISCV_CALL: case R_RISCV_PCREL_HI20: case R_RISCV_PCREL_LO12_I: case R_RISCV_PCREL_LO12_S: case R_RISCV_32_PCREL: case R_RISCV_ADD32: case R_RISCV_ADD64: case R_RISCV_SUB32: case R_RISCV_SUB64: case R_RISCV_32: case R_RISCV_64: case R_RISCV_JAL: case R_RISCV_CALL_PLT: return AUTO_GOTPLT_ENTRY; case R_RISCV_GOT_HI20: return ALWAYS_GOTPLT_ENTRY; } return -1; } ST_FUNC unsigned create_plt_entry(TCCState *s1, unsigned got_offset, struct sym_attr *attr) { Section *plt = s1->plt; uint8_t *p; unsigned plt_offset; if (s1->output_type == TCC_OUTPUT_DLL) tcc_error("DLLs unimplemented!"); if (plt->data_offset == 0) section_ptr_add(plt, 32); plt_offset = plt->data_offset; p = section_ptr_add(plt, 16); write64le(p, got_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) { uint64_t plt = s1->plt->sh_addr; uint64_t got = s1->got->sh_addr; uint64_t off = (got - plt + 0x800) >> 12; if ((off + ((uint32_t)1 << 20)) >> 21) tcc_error("Failed relocating PLT (off=0x%lx, got=0x%lx, plt=0x%lx)", off, got, plt); write32le(p, 0x397 | (off << 12)); // auipc t2, %pcrel_hi(got) write32le(p + 4, 0x41c30333); // sub t1, t1, t3 write32le(p + 8, 0x0003be03 // ld t3, %pcrel_lo(got)(t2) | (((got - plt) & 0xfff) << 20)); write32le(p + 12, 0xfd430313); // addi t1, t1, -(32+12) write32le(p + 16, 0x00038293 // addi t0, t2, %pcrel_lo(got) | (((got - plt) & 0xfff) << 20)); write32le(p + 20, 0x00135313); // srli t1, t1, log2(16/PTRSIZE) write32le(p + 24, 0x0082b283); // ld t0, PTRSIZE(t0) write32le(p + 28, 0x000e0067); // jr t3 p += 32; while (p < p_end) { uint64_t pc = plt + (p - s1->plt->data); uint64_t addr = got + read64le(p); uint64_t off = (addr - pc + 0x800) >> 12; if ((off + ((uint32_t)1 << 20)) >> 21) tcc_error("Failed relocating PLT (off=0x%lx, addr=0x%lx, pc=0x%lx)", off, addr, pc); write32le(p, 0xe17 | (off << 12)); // auipc t3, %pcrel_hi(func@got) write32le(p + 4, 0x000e3e03 // ld t3, %pcrel_lo(func@got)(t3) | (((addr - pc) & 0xfff) << 20)); write32le(p + 8, 0x000e0367); // jalr t1, t3 write32le(p + 12, 0x00000013); // nop p += 16; } } } struct pcrel_hi { addr_t addr, val; }; static struct pcrel_hi last_hi; void relocate(TCCState *s1, ElfW_Rel *rel, int type, unsigned char *ptr, addr_t addr, addr_t val) { uint64_t off64; uint32_t off32; int sym_index = ELFW(R_SYM)(rel->r_info); ElfW(Sym) *sym = &((ElfW(Sym) *)symtab_section->data)[sym_index]; switch(type) { case R_RISCV_ALIGN: case R_RISCV_RELAX: return; case R_RISCV_BRANCH: off64 = val - addr; if ((off64 + (1 << 12)) & ~(uint64_t)0x1ffe) tcc_error("R_RISCV_BRANCH relocation failed" " (val=%lx, addr=%lx)", val, addr); off32 = off64 >> 1; write32le(ptr, (read32le(ptr) & ~0xfe000f80) | ((off32 & 0x800) << 20) | ((off32 & 0x3f0) << 21) | ((off32 & 0x00f) << 8) | ((off32 & 0x400) >> 3)); return; case R_RISCV_JAL: off64 = val - addr; if ((off64 + (1 << 21)) & ~(((uint64_t)1 << 22) - 2)) tcc_error("R_RISCV_JAL relocation failed" " (val=%lx, addr=%lx)", val, addr); off32 = off64; write32le(ptr, (read32le(ptr) & 0xfff) | (((off32 >> 12) & 0xff) << 12) | (((off32 >> 11) & 1) << 20) | (((off32 >> 1) & 0x3ff) << 21) | (((off32 >> 20) & 1) << 31)); return; case R_RISCV_CALL: case R_RISCV_CALL_PLT: write32le(ptr, (read32le(ptr) & 0xfff) | ((val - addr + 0x800) & ~0xfff)); write32le(ptr + 4, (read32le(ptr + 4) & 0xfffff) | (((val - addr) & 0xfff) << 20)); return; case R_RISCV_PCREL_HI20: #ifdef DEBUG_RELOC printf("PCREL_HI20: val=%lx addr=%lx\n", val, addr); #endif off64 = (int64_t)(val - addr + 0x800) >> 12; if ((off64 + ((uint64_t)1 << 20)) >> 21) tcc_error("R_RISCV_PCREL_HI20 relocation failed: off=%lx cond=%lx sym=%s", off64, ((int64_t)(off64 + ((uint64_t)1 << 20)) >> 21), symtab_section->link->data + sym->st_name); write32le(ptr, (read32le(ptr) & 0xfff) | ((off64 & 0xfffff) << 12)); last_hi.addr = addr; last_hi.val = val; return; case R_RISCV_GOT_HI20: val = s1->got->sh_addr + get_sym_attr(s1, sym_index, 0)->got_offset; off64 = (int64_t)(val - addr + 0x800) >> 12; if ((off64 + ((uint64_t)1 << 20)) >> 21) tcc_error("R_RISCV_GOT_HI20 relocation failed"); last_hi.addr = addr; last_hi.val = val; write32le(ptr, (read32le(ptr) & 0xfff) | ((off64 & 0xfffff) << 12)); return; case R_RISCV_PCREL_LO12_I: #ifdef DEBUG_RELOC printf("PCREL_LO12_I: val=%lx addr=%lx\n", val, addr); #endif if (val != last_hi.addr) tcc_error("unsupported hi/lo pcrel reloc scheme"); val = last_hi.val; addr = last_hi.addr; write32le(ptr, (read32le(ptr) & 0xfffff) | (((val - addr) & 0xfff) << 20)); return; case R_RISCV_PCREL_LO12_S: if (val != last_hi.addr) tcc_error("unsupported hi/lo pcrel reloc scheme"); val = last_hi.val; addr = last_hi.addr; off32 = val - addr; write32le(ptr, (read32le(ptr) & ~0xfe000f80) | ((off32 & 0xfe0) << 20) | ((off32 & 0x01f) << 7)); return; case R_RISCV_RVC_BRANCH: off64 = (val - addr); if ((off64 + (1 << 8)) & ~(uint64_t)0x1fe) tcc_error("R_RISCV_RVC_BRANCH relocation failed" " (val=%lx, addr=%lx)", val, addr); off32 = off64; write16le(ptr, (read16le(ptr) & 0xe383) | (((off32 >> 5) & 1) << 2) | (((off32 >> 1) & 3) << 3) | (((off32 >> 6) & 3) << 5) | (((off32 >> 3) & 3) << 10) | (((off32 >> 8) & 1) << 12)); return; case R_RISCV_RVC_JUMP: off64 = (val - addr); if ((off64 + (1 << 11)) & ~(uint64_t)0xffe) tcc_error("R_RISCV_RVC_BRANCH relocation failed" " (val=%lx, addr=%lx)", val, addr); off32 = off64; write16le(ptr, (read16le(ptr) & 0xe003) | (((off32 >> 5) & 1) << 2) | (((off32 >> 1) & 7) << 3) | (((off32 >> 7) & 1) << 6) | (((off32 >> 6) & 1) << 7) | (((off32 >> 10) & 1) << 8) | (((off32 >> 8) & 3) << 9) | (((off32 >> 4) & 1) << 11) | (((off32 >> 11) & 1) << 12)); return; case R_RISCV_32: write32le(ptr, val); return; case R_RISCV_JUMP_SLOT: case R_RISCV_64: write64le(ptr, val); return; case R_RISCV_ADD64: write64le(ptr, read64le(ptr) + val); return; case R_RISCV_ADD32: write32le(ptr, read32le(ptr) + val); return; case R_RISCV_SUB64: write64le(ptr, read64le(ptr) - val); return; case R_RISCV_SUB32: write32le(ptr, read32le(ptr) - val); return; case R_RISCV_ADD16: write16le(ptr, read16le(ptr) + val); return; case R_RISCV_SUB16: write16le(ptr, read16le(ptr) - val); return; case R_RISCV_SET6: *ptr = (*ptr & ~0x3f) | (val & 0x3f); return; case R_RISCV_SUB6: *ptr = (*ptr & ~0x3f) | ((*ptr - val) & 0x3f); return; case R_RISCV_32_PCREL: case R_RISCV_COPY: /* XXX */ return; default: fprintf(stderr, "FIXME: handle reloc type %x at %x [%p] to %x\n", type, (unsigned)addr, ptr, (unsigned)val); return; } } #endif