lol

1 files changed, 352 insertions, 0 deletions

diff --git a/tinycc/riscv64-link.c b/tinycc/riscv64-link.c
new file mode 100644
index 0000000..34bfeb0
--- /dev/null
+++ b/tinycc/riscv64-link.c
@@ -0,0 +1,352 @@
+#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 (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_noabort("Failed relocating PLT (off=0x%lx, got=0x%lx, plt=0x%lx)", (long)off, (long)got, (long)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_noabort("Failed relocating PLT (off=0x%lx, addr=0x%lx, pc=0x%lx)", (long)off, (long)addr, (long)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;
+        }
+    }
+
+    if (s1->plt->reloc) {
+        ElfW_Rel *rel;
+        p = s1->got->data;
+        for_each_elem(s1->plt->reloc, 0, rel, ElfW_Rel) {
+            write64le(p + rel->r_offset, s1->plt->sh_addr);
+	}
+    }
+}
+
+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), esym_index;
+    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_noabort("R_RISCV_BRANCH relocation failed"
+                    " (val=%lx, addr=%lx)", (long)val, (long)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_noabort("R_RISCV_JAL relocation failed"
+                    " (val=%lx, addr=%lx)", (long)val, (long)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", (long)val, (long)addr);
+#endif
+        off64 = (int64_t)(val - addr + 0x800) >> 12;
+        if ((off64 + ((uint64_t)1 << 20)) >> 21)
+          tcc_error_noabort("R_RISCV_PCREL_HI20 relocation failed: off=%lx cond=%lx sym=%s",
+                    (long)off64, (long)((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_noabort("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", (long)val, (long)addr);
+#endif
+        if (val != last_hi.addr)
+          tcc_error_noabort("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_noabort("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_noabort("R_RISCV_RVC_BRANCH relocation failed"
+                    " (val=%lx, addr=%lx)", (long)val, (long)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_noabort("R_RISCV_RVC_BRANCH relocation failed"
+                    " (val=%lx, addr=%lx)", (long)val, (long)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:
+        if (s1->output_type & TCC_OUTPUT_DYN) {
+            /* XXX: this logic may depend on TCC's codegen
+               now TCC uses R_RISCV_RELATIVE even for a 64bit pointer */
+            qrel->r_offset = rel->r_offset;
+            qrel->r_info = ELFW(R_INFO)(0, R_RISCV_RELATIVE);
+            /* Use sign extension! */
+            qrel->r_addend = (int)read32le(ptr) + val;
+            qrel++;
+        }
+        add32le(ptr, val);
+        return;
+    case R_RISCV_64:
+        if (s1->output_type & TCC_OUTPUT_DYN) {
+            esym_index = get_sym_attr(s1, sym_index, 0)->dyn_index;
+            qrel->r_offset = rel->r_offset;
+            if (esym_index) {
+                qrel->r_info = ELFW(R_INFO)(esym_index, R_RISCV_64);
+                qrel->r_addend = rel->r_addend;
+                qrel++;
+                break;
+            } else {
+                qrel->r_info = ELFW(R_INFO)(0, R_RISCV_RELATIVE);
+                qrel->r_addend = read64le(ptr) + val;
+                qrel++;
+            }
+        }
+    case R_RISCV_JUMP_SLOT:
+        add64le(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