lol

1 files changed, 403 insertions, 0 deletions

diff --git a/tinycc/x86_64-link.c b/tinycc/x86_64-link.c
new file mode 100644
index 0000000..1b6aa09
--- /dev/null
+++ b/tinycc/x86_64-link.c
@@ -0,0 +1,403 @@
+#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"
+
+#ifdef NEED_RELOC_TYPE
+/* 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:
+        case R_X86_64_TLSGD:
+        case R_X86_64_TLSLD:
+        case R_X86_64_DTPOFF32:
+        case R_X86_64_TPOFF32:
+        case R_X86_64_DTPOFF64:
+        case R_X86_64_TPOFF64:
+            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;
+    }
+    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_TLSGD:
+        case R_X86_64_TLSLD:
+        case R_X86_64_DTPOFF32:
+        case R_X86_64_TPOFF32:
+        case R_X86_64_DTPOFF64:
+        case R_X86_64_TPOFF64:
+        case R_X86_64_REX_GOTPCRELX:
+        case R_X86_64_PLT32:
+        case R_X86_64_PLTOFF64:
+            return ALWAYS_GOTPLT_ENTRY;
+    }
+
+    return -1;
+}
+
+#ifdef NEED_BUILD_GOT
+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->plt->reloc ? s1->plt->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) - 1);
+    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;
+        }
+    }
+
+    if (s1->plt->reloc) {
+        ElfW_Rel *rel;
+        int x = s1->plt->sh_addr + 16 + 6;
+        p = s1->got->data;
+        for_each_elem(s1->plt->reloc, 0, rel, ElfW_Rel) {
+            write64le(p + rel->r_offset, x);
+            x += 16;
+        }
+    }
+}
+#endif
+#endif
+
+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_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_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_DYN) {
+                /* XXX: this logic may depend on TCC's codegen
+                   now TCC uses R_X86_64_32 even for a 64bit pointer */
+                qrel->r_offset = rel->r_offset;
+                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 = get_sym_attr(s1, sym_index, 0)->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) {
+#ifdef TCC_TARGET_PE
+              /* ignore overflow with undefined weak symbols */
+              if (((ElfW(Sym)*)symtab_section->data)[sym_index].st_shndx != SHN_UNDEF)
+#endif
+                tcc_error_noabort("internal error: relocation failed");
+            }
+            add32le(ptr, diff);
+        }
+            break;
+
+        case R_X86_64_COPY:
+	    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 = get_sym_attr(s1, sym_index, 0)->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 +
+                         get_sym_attr(s1, sym_index, 0)->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, get_sym_attr(s1, sym_index, 0)->got_offset);
+            break;
+        case R_X86_64_GOT64:
+            /* we load the got offset */
+            add64le(ptr, get_sym_attr(s1, sym_index, 0)->got_offset);
+            break;
+        case R_X86_64_GOTOFF64:
+            add64le(ptr, val - s1->got->sh_addr);
+            break;
+        case R_X86_64_TLSGD:
+            {
+                static const unsigned char expect[] = {
+                    /* .byte 0x66; lea 0(%rip),%rdi */
+                    0x66, 0x48, 0x8d, 0x3d, 0x00, 0x00, 0x00, 0x00,
+                    /* .word 0x6666; rex64; call __tls_get_addr@PLT */
+                    0x66, 0x66, 0x48, 0xe8, 0x00, 0x00, 0x00, 0x00 };
+                static const unsigned char replace[] = {
+                    /* mov %fs:0,%rax */
+                    0x64, 0x48, 0x8b, 0x04, 0x25, 0x00, 0x00, 0x00, 0x00,
+                    /* lea -4(%rax),%rax */
+                    0x48, 0x8d, 0x80, 0x00, 0x00, 0x00, 0x00 };
+
+                if (memcmp (ptr-4, expect, sizeof(expect)) == 0) {
+                    ElfW(Sym) *sym;
+                    Section *sec;
+                    int32_t x;
+
+                    memcpy(ptr-4, replace, sizeof(replace));
+                    rel[1].r_info = ELFW(R_INFO)(0, R_X86_64_NONE);
+                    sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
+                    sec = s1->sections[sym->st_shndx];
+                    x = sym->st_value - sec->sh_addr - sec->data_offset;
+                    add32le(ptr + 8, x);
+                }
+                else
+                    tcc_error_noabort("unexpected R_X86_64_TLSGD pattern");
+            }
+            break;
+        case R_X86_64_TLSLD:
+            {
+                static const unsigned char expect[] = {
+                    /* lea 0(%rip),%rdi */
+                    0x48, 0x8d, 0x3d, 0x00, 0x00, 0x00, 0x00,
+                    /* call __tls_get_addr@PLT */
+                    0xe8, 0x00, 0x00, 0x00, 0x00 };
+                static const unsigned char replace[] = {
+                    /* data16 data16 data16 mov %fs:0,%rax */
+                    0x66, 0x66, 0x66, 0x64, 0x48, 0x8b, 0x04, 0x25,
+                    0x00, 0x00, 0x00, 0x00 };
+
+                if (memcmp (ptr-3, expect, sizeof(expect)) == 0) {
+                    memcpy(ptr-3, replace, sizeof(replace));
+                    rel[1].r_info = ELFW(R_INFO)(0, R_X86_64_NONE);
+                }
+                else
+                    tcc_error_noabort("unexpected R_X86_64_TLSLD pattern");
+            }
+            break;
+        case R_X86_64_DTPOFF32:
+        case R_X86_64_TPOFF32:
+            {
+                ElfW(Sym) *sym;
+                Section *sec;
+                int32_t x;
+
+                sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
+                sec = s1->sections[sym->st_shndx];
+                x = val - sec->sh_addr - sec->data_offset;
+                add32le(ptr, x);
+            }
+            break;
+        case R_X86_64_DTPOFF64:
+        case R_X86_64_TPOFF64:
+            {
+                ElfW(Sym) *sym;
+                Section *sec;
+                int32_t x;
+
+                sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
+                sec = s1->sections[sym->st_shndx];
+                x = val - sec->sh_addr - sec->data_offset;
+                add64le(ptr, x);
+            }
+            break;
+        case R_X86_64_NONE:
+            break;
+        case R_X86_64_RELATIVE:
+#ifdef TCC_TARGET_PE
+            add32le(ptr, val - s1->pe_imagebase);
+#endif
+            /* do nothing */
+            break;
+        default:
+            fprintf(stderr,"FIXME: handle reloc type %d at %x [%p] to %x\n",
+                type, (unsigned)addr, ptr, (unsigned)val);
+            break;
+    }
+}
+
+#endif /* !TARGET_DEFS_ONLY */