/*-
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2019 Hesham Almatary
*
* This software was developed by SRI International and the University of
* Cambridge Computer Laboratory (Department of Computer Science and
* Technology) under DARPA contract HR0011-18-C-0016 ("ECATS"), as part of the
* DARPA SSITH research programme.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/* Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
* See https://llvm.org/LICENSE.txt for license information.
* SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
*/
#include <sys/cdefs.h>
#include <errno.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <rtems/rtl/rtl.h>
#include "rtl-elf.h"
#include "rtl-error.h"
#include <rtems/rtl/rtl-trace.h>
#include "rtl-unwind.h"
#include "rtl-unwind-dw2.h"
uint32_t
rtems_rtl_elf_section_flags (const rtems_rtl_obj* obj,
const Elf_Shdr* shdr) {
return 0;
}
uint32_t
rtems_rtl_elf_arch_parse_section (const rtems_rtl_obj* obj,
int section,
const char* name,
const Elf_Shdr* shdr,
const uint32_t flags) {
(void) obj;
(void) section;
(void) name;
(void) shdr;
return flags;
}
bool
rtems_rtl_elf_arch_section_alloc (const rtems_rtl_obj* obj,
rtems_rtl_obj_sect* sect) {
(void) obj;
(void) sect;
return false;
}
bool
rtems_rtl_elf_arch_section_free (const rtems_rtl_obj* obj,
rtems_rtl_obj_sect* sect) {
(void) obj;
(void) sect;
return false;
}
bool
rtems_rtl_elf_rel_resolve_sym (Elf_Word type) {
return true;
}
uint32_t rtems_rtl_obj_tramp_alignment (const rtems_rtl_obj* obj)
{
(void) obj;
return sizeof(uint32_t);
}
size_t
rtems_rtl_elf_relocate_tramp_max_size (void) {
/*
* Disable by returning 0.
*/
return 0;
}
rtems_rtl_elf_rel_status
rtems_rtl_elf_relocate_rel_tramp (rtems_rtl_obj* obj,
const Elf_Rel* rel,
const rtems_rtl_obj_sect* sect,
const char* symname,
const Elf_Byte syminfo,
const Elf_Word symvalue) {
(void) obj;
(void) rel;
(void) sect;
(void) symname;
(void) syminfo;
(void) symvalue;
return rtems_rtl_elf_rel_no_error;
}
// Extract bits V[Begin:End], where range is inclusive, and Begin must be < 63.
static uint32_t extractBits(uint64_t v, uint32_t begin, uint32_t end) {
return (v & ((1ULL << (begin + 1)) - 1)) >> end;
}
static int64_t SignExtend64(uint64_t val, unsigned bits) {
return (int64_t )(((int64_t) (val << (64 - bits))) >> (64 - bits));
}
static void write16le(void *loc, uint16_t val) {
*((uint16_t *) loc) = val;
}
static void write32le(void *loc, uint32_t val) {
*((uint32_t *) loc) = val;
}
static void write64le(void *loc, uint64_t val) {
*((uint64_t *) loc) = val;
}
static uint16_t read16le(void *loc) {
return *((uint16_t *) loc);
}
static uint32_t read32le(void *loc) {
return *((uint32_t *) loc);
}
static uint64_t read64le(void *loc) {
return *((uint64_t *) loc);
}
static rtems_rtl_elf_rel_status
rtems_rtl_elf_reloc_rela (rtems_rtl_obj* obj,
const Elf_Rela* rela,
const rtems_rtl_obj_sect* sect,
const char* symname,
const Elf_Byte syminfo,
const Elf_Word symvalue,
const bool parsing) {
Elf_Word *where;
Elf_Word tmp;
Elf_Word addend = (Elf_Word) rela->r_addend;
Elf_Word local = 0;
char bits = (sizeof(Elf_Word) * 8);
where = (Elf_Addr *)(sect->base + rela->r_offset);
// Final PCREL value
Elf_Word pcrel_val = symvalue - ((Elf_Word) where);
if (syminfo == STT_SECTION) {
local = 1;
return rtems_rtl_elf_rel_no_error;
}
if (parsing) {
return rtems_rtl_elf_rel_no_error;
}
switch (ELF_R_TYPE(rela->r_info)) {
case R_TYPE(NONE):
break;
case R_TYPE(RVC_BRANCH): {
uint16_t insn = ((*where) & 0xFFFF) & 0xE383;
uint16_t imm8 = extractBits(pcrel_val, 8, 8) << 12;
uint16_t imm4_3 = extractBits(pcrel_val, 4, 3) << 10;
uint16_t imm7_6 = extractBits(pcrel_val, 7, 6) << 5;
uint16_t imm2_1 = extractBits(pcrel_val, 2, 1) << 3;
uint16_t imm5 = extractBits(pcrel_val, 5, 5) << 2;
insn |= imm8 | imm4_3 | imm7_6 | imm2_1 | imm5;
write16le(where, insn);
}
break;
case R_TYPE(RVC_JUMP): {
uint16_t insn = ((*where) & 0xFFFF) & 0xE003;
uint16_t imm11 = extractBits(pcrel_val, 11, 11) << 12;
uint16_t imm4 = extractBits(pcrel_val, 4, 4) << 11;
uint16_t imm9_8 = extractBits(pcrel_val, 9, 8) << 9;
uint16_t imm10 = extractBits(pcrel_val, 10, 10) << 8;
uint16_t imm6 = extractBits(pcrel_val, 6, 6) << 7;
uint16_t imm7 = extractBits(pcrel_val, 7, 7) << 6;
uint16_t imm3_1 = extractBits(pcrel_val, 3, 1) << 3;
uint16_t imm5 = extractBits(pcrel_val, 5, 5) << 2;
insn |= imm11 | imm4 | imm9_8 | imm10 | imm6 | imm7 | imm3_1 | imm5;
write16le(where, insn);
}
break;
case R_TYPE(RVC_LUI): {
int64_t imm = SignExtend64(symvalue + 0x800, bits) >> 12;
if (imm == 0) { // `c.lui rd, 0` is illegal, convert to `c.li rd, 0`
write16le(where, (read16le(where) & 0x0F83) | 0x4000);
} else {
uint16_t imm17 = extractBits(symvalue + 0x800, 17, 17) << 12;
uint16_t imm16_12 = extractBits(symvalue + 0x800, 16, 12) << 2;
write16le(where, (read16le(where) & 0xEF83) | imm17 | imm16_12);
}
}
break;
case R_TYPE(JAL): {
uint32_t insn = read32le(where) & 0xFFF;
uint32_t imm20 = extractBits(pcrel_val, 20, 20) << 31;
uint32_t imm10_1 = extractBits(pcrel_val, 10, 1) << 21;
uint32_t imm11 = extractBits(pcrel_val, 11, 11) << 20;
uint32_t imm19_12 = extractBits(pcrel_val, 19, 12) << 12;
insn |= imm20 | imm10_1 | imm11 | imm19_12;
write32le(where, insn);
}
break;
case R_TYPE(BRANCH): {
uint32_t insn = read32le(where) & 0x1FFF07F;
uint32_t imm12 = extractBits(pcrel_val, 12, 12) << 31;
uint32_t imm10_5 = extractBits(pcrel_val, 10, 5) << 25;
uint32_t imm4_1 = extractBits(pcrel_val, 4, 1) << 8;
uint32_t imm11 = extractBits(pcrel_val, 11, 11) << 7;
insn |= imm12 | imm10_5 | imm4_1 | imm11;
write32le(where, insn);
}
break;
case R_TYPE(64):
write64le(where, symvalue);
break;
case R_TYPE(32):
write32le(where, symvalue);
break;
case R_TYPE(SET6):
*((uint8_t *) where) = (*where & 0xc0) | (symvalue & 0x3f);
break;
case R_TYPE(SET8):
*((uint8_t *) where) = symvalue;
break;
case R_TYPE(SET16):
write16le(where, symvalue);
break;
case R_TYPE(SET32):
write32le(where, symvalue);
break;
case R_TYPE(ADD8):
*((uint8_t *) where) = *((uint8_t *) where) + symvalue;
break;
case R_TYPE(ADD16):
write16le(where, read16le(where) + symvalue);
break;
case R_TYPE(ADD32):
write32le(where, read32le(where) + symvalue);
break;
case R_TYPE(ADD64):
write64le(where, read64le(where) + symvalue);
break;
case R_TYPE(SUB6):
*((uint8_t *) where) = (*where & 0xc0) | (((*where & 0x3f) - symvalue) & 0x3f);
break;
case R_TYPE(SUB8):
*((uint8_t *) where) = *((uint8_t *) where) - symvalue;
break;
case R_TYPE(SUB16):
write16le(where, read16le(where) - symvalue);
break;
case R_TYPE(SUB32):
write32le(where, read32le(where) - symvalue);
break;
case R_TYPE(SUB64):
write64le(where, read64le(where) - symvalue);
break;
case R_TYPE(32_PCREL): {
write32le(where, pcrel_val);
if (rtems_rtl_trace (RTEMS_RTL_TRACE_RELOC))
printf ("rtl: R_RISCV_32_PCREL %p @ %p in %s\n",
(void *) * (where), where, rtems_rtl_obj_oname (obj));
}
break;
case R_TYPE(PCREL_HI20): {
int64_t hi = SignExtend64(pcrel_val + 0x800, bits); //pcrel_val + 0x800;
write32le(where, (read32le(where) & 0xFFF) | (hi & 0xFFFFF000));
}
break;
case R_TYPE(GOT_HI20):
case R_TYPE(HI20): {
uint64_t hi = symvalue + 0x800;
write32le(where, (read32le(where) & 0xFFF) | (hi & 0xFFFFF000));
}
break;
case R_TYPE(PCREL_LO12_I): {
uint64_t hi = (pcrel_val + 0x800) >> 12;
uint64_t lo = pcrel_val - (hi << 12);
write32le(where, (read32le(where) & 0xFFFFF) | ((lo & 0xFFF) << 20));
}
break;
case R_TYPE(LO12_I): {
uint64_t hi = (symvalue + 0x800) >> 12;
uint64_t lo = symvalue - (hi << 12);
write32le(where, (read32le(where) & 0xFFFFF) | ((lo & 0xFFF) << 20));
}
break;
case R_TYPE(PCREL_LO12_S): {
uint64_t hi = (pcrel_val + 0x800) >> 12;
uint64_t lo = pcrel_val - (hi << 12);
uint32_t imm11_5 = extractBits(lo, 11, 5) << 25;
uint32_t imm4_0 = extractBits(lo, 4, 0) << 7;
write32le(where, (read32le(where) & 0x1FFF07F) | imm11_5 | imm4_0);
}
break;
case R_TYPE(LO12_S): {
uint64_t hi = (symvalue + 0x800) >> 12;
uint64_t lo = symvalue - (hi << 12);
uint32_t imm11_5 = extractBits(lo, 11, 5) << 25;
uint32_t imm4_0 = extractBits(lo, 4, 0) << 7;
write32le(where, (read32le(where) & 0x1FFF07F) | imm11_5 | imm4_0);
}
break;
case R_TYPE(CALL_PLT):
case R_TYPE(CALL): {
int64_t hi = SignExtend64(pcrel_val + 0x800, bits);
write32le(where, (read32le(where) & 0xFFF) | (hi & 0xFFFFF000));
int64_t hi20 = SignExtend64(pcrel_val + 0x800, bits);
int64_t lo = pcrel_val - (hi20 << 12);
write32le(((char *) where) + 4, (read32le(((char *) where) + 4) & 0xFFFFF) | ((lo & 0xFFF) << 20));
}
break;
default:
rtems_rtl_set_error (EINVAL,
"%s: Unsupported relocation type %ld "
"in non-PLT relocations",
sect->name, (uint32_t) ELF_R_TYPE(rela->r_info));
return rtems_rtl_elf_rel_failure;
}
return rtems_rtl_elf_rel_no_error;
}
rtems_rtl_elf_rel_status
rtems_rtl_elf_relocate_rela (rtems_rtl_obj* obj,
const Elf_Rela* rela,
const rtems_rtl_obj_sect* sect,
const char* symname,
const Elf_Byte syminfo,
const Elf_Word symvalue) {
return rtems_rtl_elf_reloc_rela (obj,
rela,
sect,
symname,
syminfo,
symvalue,
false);
}
rtems_rtl_elf_rel_status
rtems_rtl_elf_relocate_rela_tramp (rtems_rtl_obj* obj,
const Elf_Rela* rela,
const rtems_rtl_obj_sect* sect,
const char* symname,
const Elf_Byte syminfo,
const Elf_Word symvalue) {
return rtems_rtl_elf_reloc_rela (obj,
rela,
sect,
symname,
syminfo,
symvalue,
true);
}
rtems_rtl_elf_rel_status
rtems_rtl_elf_relocate_rel (rtems_rtl_obj* obj,
const Elf_Rel* rel,
const rtems_rtl_obj_sect* sect,
const char* symname,
const Elf_Byte syminfo,
const Elf_Word symvalue) {
rtems_rtl_set_error (EINVAL, "rel type record not supported");
return rtems_rtl_elf_rel_failure;
}
bool
rtems_rtl_elf_unwind_parse (const rtems_rtl_obj* obj,
const char* name,
uint32_t flags) {
return rtems_rtl_elf_unwind_dw2_parse (obj, name, flags);
}
bool
rtems_rtl_elf_unwind_register (rtems_rtl_obj* obj) {
return rtems_rtl_elf_unwind_dw2_register (obj);
}
bool
rtems_rtl_elf_unwind_deregister (rtems_rtl_obj* obj) {
return rtems_rtl_elf_unwind_dw2_deregister (obj);
}
