tinycc/riscv64-link.c
grischka 72729d8e36 allow libtcc states to be used concurrently
This allows creation of TCCStates and operation with API
calls independently from each other, even from threads.

Frontend (option parsing/libtcc.c) and backend (linker/tccelf.c)
now depend only on the TCCState (s1) argument.

Compilation per se (tccpp.c, tccgen.c) is still using
globals for convenience.  There is only one entry point
to this section which is tcc_compile() which is protected
by a semaphore.

There are some hacks involved to avoid too many changes,
as well as some changes in order to avoid too many hacks ;)

The test libtcc_test_mt.c shows the feature.  Except this
new file the patch adds 87 lines overall.
2019-12-11 02:36:19 +01:00

330 lines
10 KiB
C

#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