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authorbellard <bellard@c046a42c-6fe2-441c-8c8c-71466251a162>2003-03-01 17:13:26 +0000
committerbellard <bellard@c046a42c-6fe2-441c-8c8c-71466251a162>2003-03-01 17:13:26 +0000
commit367e86e8476d6373a00d0e56a29b03c4b8f3e2ee (patch)
tree3cfad136fffefb2c5d8635b3b82fe4a587b4f1f4 /dyngen.c
parent7bfdb6d18c7bb5792c896a0bf6cf1ad7431630cb (diff)
new x86 CPU core
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@14 c046a42c-6fe2-441c-8c8c-71466251a162
Diffstat (limited to 'dyngen.c')
-rw-r--r--dyngen.c521
1 files changed, 521 insertions, 0 deletions
diff --git a/dyngen.c b/dyngen.c
new file mode 100644
index 000000000..ff10891b9
--- /dev/null
+++ b/dyngen.c
@@ -0,0 +1,521 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdarg.h>
+#include <inttypes.h>
+#include <elf.h>
+#include <unistd.h>
+#include <fcntl.h>
+
+#include "thunk.h"
+
+/* all dynamically generated functions begin with this code */
+#define OP_PREFIX "op"
+
+int elf_must_swap(Elf32_Ehdr *h)
+{
+ union {
+ uint32_t i;
+ uint8_t b[4];
+ } swaptest;
+
+ swaptest.i = 1;
+ return (h->e_ident[EI_DATA] == ELFDATA2MSB) !=
+ (swaptest.b[0] == 0);
+}
+
+void swab16s(uint16_t *p)
+{
+ *p = bswap16(*p);
+}
+
+void swab32s(uint32_t *p)
+{
+ *p = bswap32(*p);
+}
+
+void swab64s(uint32_t *p)
+{
+ *p = bswap64(*p);
+}
+
+void elf_swap_ehdr(Elf32_Ehdr *h)
+{
+ swab16s(&h->e_type); /* Object file type */
+ swab16s(&h-> e_machine); /* Architecture */
+ swab32s(&h-> e_version); /* Object file version */
+ swab32s(&h-> e_entry); /* Entry point virtual address */
+ swab32s(&h-> e_phoff); /* Program header table file offset */
+ swab32s(&h-> e_shoff); /* Section header table file offset */
+ swab32s(&h-> e_flags); /* Processor-specific flags */
+ swab16s(&h-> e_ehsize); /* ELF header size in bytes */
+ swab16s(&h-> e_phentsize); /* Program header table entry size */
+ swab16s(&h-> e_phnum); /* Program header table entry count */
+ swab16s(&h-> e_shentsize); /* Section header table entry size */
+ swab16s(&h-> e_shnum); /* Section header table entry count */
+ swab16s(&h-> e_shstrndx); /* Section header string table index */
+}
+
+void elf_swap_shdr(Elf32_Shdr *h)
+{
+ swab32s(&h-> sh_name); /* Section name (string tbl index) */
+ swab32s(&h-> sh_type); /* Section type */
+ swab32s(&h-> sh_flags); /* Section flags */
+ swab32s(&h-> sh_addr); /* Section virtual addr at execution */
+ swab32s(&h-> sh_offset); /* Section file offset */
+ swab32s(&h-> sh_size); /* Section size in bytes */
+ swab32s(&h-> sh_link); /* Link to another section */
+ swab32s(&h-> sh_info); /* Additional section information */
+ swab32s(&h-> sh_addralign); /* Section alignment */
+ swab32s(&h-> sh_entsize); /* Entry size if section holds table */
+}
+
+void elf_swap_phdr(Elf32_Phdr *h)
+{
+ swab32s(&h->p_type); /* Segment type */
+ swab32s(&h->p_offset); /* Segment file offset */
+ swab32s(&h->p_vaddr); /* Segment virtual address */
+ swab32s(&h->p_paddr); /* Segment physical address */
+ swab32s(&h->p_filesz); /* Segment size in file */
+ swab32s(&h->p_memsz); /* Segment size in memory */
+ swab32s(&h->p_flags); /* Segment flags */
+ swab32s(&h->p_align); /* Segment alignment */
+}
+
+int do_swap;
+int e_machine;
+
+uint16_t get16(uint16_t *p)
+{
+ uint16_t val;
+ val = *p;
+ if (do_swap)
+ val = bswap16(val);
+ return val;
+}
+
+uint32_t get32(uint32_t *p)
+{
+ uint32_t val;
+ val = *p;
+ if (do_swap)
+ val = bswap32(val);
+ return val;
+}
+
+void put16(uint16_t *p, uint16_t val)
+{
+ if (do_swap)
+ val = bswap16(val);
+ *p = val;
+}
+
+void put32(uint32_t *p, uint32_t val)
+{
+ if (do_swap)
+ val = bswap32(val);
+ *p = val;
+}
+
+void __attribute__((noreturn)) error(const char *fmt, ...)
+{
+ va_list ap;
+ va_start(ap, fmt);
+ fprintf(stderr, "dyngen: ");
+ vfprintf(stderr, fmt, ap);
+ fprintf(stderr, "\n");
+ va_end(ap);
+ exit(1);
+}
+
+
+Elf32_Shdr *find_elf_section(Elf32_Shdr *shdr, int shnum, const char *shstr,
+ const char *name)
+{
+ int i;
+ const char *shname;
+ Elf32_Shdr *sec;
+
+ for(i = 0; i < shnum; i++) {
+ sec = &shdr[i];
+ if (!sec->sh_name)
+ continue;
+ shname = shstr + sec->sh_name;
+ if (!strcmp(shname, name))
+ return sec;
+ }
+ return NULL;
+}
+
+void *load_data(int fd, long offset, unsigned int size)
+{
+ char *data;
+
+ data = malloc(size);
+ if (!data)
+ return NULL;
+ lseek(fd, offset, SEEK_SET);
+ if (read(fd, data, size) != size) {
+ free(data);
+ return NULL;
+ }
+ return data;
+}
+
+int strstart(const char *str, const char *val, const char **ptr)
+{
+ const char *p, *q;
+ p = str;
+ q = val;
+ while (*q != '\0') {
+ if (*p != *q)
+ return 0;
+ p++;
+ q++;
+ }
+ if (ptr)
+ *ptr = p;
+ return 1;
+}
+
+#define MAX_ARGS 3
+
+/* generate op code */
+void gen_code(const char *name, unsigned long offset, unsigned long size,
+ FILE *outfile, uint8_t *text, void *relocs, int nb_relocs, int reloc_sh_type,
+ Elf32_Sym *symtab, char *strtab)
+{
+ int copy_size = 0;
+ uint8_t *p_start, *p_end;
+ int nb_args, i;
+ uint8_t args_present[MAX_ARGS];
+ const char *sym_name, *p;
+
+ /* compute exact size excluding return instruction */
+ p_start = text + offset;
+ p_end = p_start + size;
+ switch(e_machine) {
+ case EM_386:
+ {
+ uint8_t *p;
+ p = p_end - 1;
+ /* find ret */
+ while (p > p_start && *p != 0xc3)
+ p--;
+ /* skip double ret */
+ if (p > p_start && p[-1] == 0xc3)
+ p--;
+ if (p == p_start)
+ error("empty code for %s", name);
+ copy_size = p - p_start;
+ }
+ break;
+ case EM_PPC:
+ {
+ uint8_t *p;
+ p = (void *)(p_end - 4);
+ /* find ret */
+ while (p > p_start && get32((uint32_t *)p) != 0x4e800020)
+ p -= 4;
+ /* skip double ret */
+ if (p > p_start && get32((uint32_t *)(p - 4)) == 0x4e800020)
+ p -= 4;
+ if (p == p_start)
+ error("empty code for %s", name);
+ copy_size = p - p_start;
+ }
+ break;
+ default:
+ error("unsupported CPU (%d)", e_machine);
+ }
+
+ /* compute the number of arguments by looking at the relocations */
+ for(i = 0;i < MAX_ARGS; i++)
+ args_present[i] = 0;
+
+ if (reloc_sh_type == SHT_REL) {
+ Elf32_Rel *rel;
+ int n;
+ for(i = 0, rel = relocs;i < nb_relocs; i++, rel++) {
+ if (rel->r_offset >= offset && rel->r_offset < offset + copy_size) {
+ sym_name = strtab + symtab[ELF32_R_SYM(rel->r_info)].st_name;
+ if (strstart(sym_name, "__op_param", &p)) {
+ n = strtoul(p, NULL, 10);
+ if (n >= MAX_ARGS)
+ error("too many arguments in %s", name);
+ args_present[n - 1] = 1;
+ }
+ }
+ }
+ } else {
+ Elf32_Rela *rel;
+ int n;
+ for(i = 0, rel = relocs;i < nb_relocs; i++, rel++) {
+ if (rel->r_offset >= offset && rel->r_offset < offset + copy_size) {
+ sym_name = strtab + symtab[ELF32_R_SYM(rel->r_info)].st_name;
+ if (strstart(sym_name, "__op_param", &p)) {
+ n = strtoul(p, NULL, 10);
+ if (n >= MAX_ARGS)
+ error("too many arguments in %s", name);
+ args_present[n - 1] = 1;
+ }
+ }
+ }
+ }
+
+ nb_args = 0;
+ while (nb_args < MAX_ARGS && args_present[nb_args])
+ nb_args++;
+ for(i = nb_args; i < MAX_ARGS; i++) {
+ if (args_present[i])
+ error("inconsistent argument numbering in %s", name);
+ }
+
+ /* output C code */
+ fprintf(outfile, "extern void %s();\n", name);
+ fprintf(outfile, "static inline void gen_%s(", name);
+ if (nb_args == 0) {
+ fprintf(outfile, "void");
+ } else {
+ for(i = 0; i < nb_args; i++) {
+ if (i != 0)
+ fprintf(outfile, ", ");
+ fprintf(outfile, "long param%d", i + 1);
+ }
+ }
+ fprintf(outfile, ")\n");
+ fprintf(outfile, "{\n");
+ fprintf(outfile, " memcpy(gen_code_ptr, &%s, %d);\n", name, copy_size);
+
+ /* patch relocations */
+ switch(e_machine) {
+ case EM_386:
+ {
+ Elf32_Rel *rel;
+ char name[256];
+ int type;
+ long addend;
+ for(i = 0, rel = relocs;i < nb_relocs; i++, rel++) {
+ if (rel->r_offset >= offset && rel->r_offset < offset + copy_size) {
+ sym_name = strtab + symtab[ELF32_R_SYM(rel->r_info)].st_name;
+ if (strstart(sym_name, "__op_param", &p)) {
+ snprintf(name, sizeof(name), "param%s", p);
+ } else {
+ snprintf(name, sizeof(name), "(long)(&%s)", sym_name);
+ }
+ type = ELF32_R_TYPE(rel->r_info);
+ addend = get32((uint32_t *)(text + rel->r_offset));
+ switch(type) {
+ case R_386_32:
+ fprintf(outfile, " *(uint32_t *)(gen_code_ptr + %ld) = %s + %ld;\n",
+ rel->r_offset - offset, name, addend);
+ break;
+ case R_386_PC32:
+ fprintf(outfile, " *(uint32_t *)(gen_code_ptr + %ld) = %s - (long)(gen_code_ptr + %ld) + %ld;\n",
+ rel->r_offset - offset, name, rel->r_offset - offset, addend);
+ break;
+ default:
+ error("unsupported i386 relocation (%d)", type);
+ }
+ }
+ }
+ }
+ break;
+ default:
+ error("unsupported CPU for relocations (%d)", e_machine);
+ }
+
+
+ fprintf(outfile, " gen_code_ptr += %d;\n", copy_size);
+ fprintf(outfile, "}\n\n");
+}
+
+/* load an elf object file */
+int load_elf(const char *filename, FILE *outfile)
+{
+ int fd;
+ Elf32_Ehdr ehdr;
+ Elf32_Shdr *sec, *shdr, *symtab_sec, *strtab_sec, *text_sec;
+ int i, j, nb_syms;
+ Elf32_Sym *symtab, *sym;
+ const char *cpu_name;
+ char *shstr, *strtab;
+ uint8_t *text;
+ void *relocs;
+ int nb_relocs, reloc_sh_type;
+
+ fd = open(filename, O_RDONLY);
+ if (fd < 0)
+ error("can't open file '%s'", filename);
+
+ /* Read ELF header. */
+ if (read(fd, &ehdr, sizeof (ehdr)) != sizeof (ehdr))
+ error("unable to read file header");
+
+ /* Check ELF identification. */
+ if (ehdr.e_ident[EI_MAG0] != ELFMAG0
+ || ehdr.e_ident[EI_MAG1] != ELFMAG1
+ || ehdr.e_ident[EI_MAG2] != ELFMAG2
+ || ehdr.e_ident[EI_MAG3] != ELFMAG3
+ || ehdr.e_ident[EI_CLASS] != ELFCLASS32
+ || ehdr.e_ident[EI_VERSION] != EV_CURRENT) {
+ error("bad ELF header");
+ }
+
+ do_swap = elf_must_swap(&ehdr);
+ if (do_swap)
+ elf_swap_ehdr(&ehdr);
+ if (ehdr.e_type != ET_REL)
+ error("ELF object file expected");
+ if (ehdr.e_version != EV_CURRENT)
+ error("Invalid ELF version");
+ e_machine = ehdr.e_machine;
+
+ /* read section headers */
+ shdr = load_data(fd, ehdr.e_shoff, ehdr.e_shnum * sizeof(Elf32_Shdr));
+ if (do_swap) {
+ for(i = 0; i < ehdr.e_shnum; i++) {
+ elf_swap_shdr(&shdr[i]);
+ }
+ }
+
+ sec = &shdr[ehdr.e_shstrndx];
+ shstr = load_data(fd, sec->sh_offset, sec->sh_size);
+
+ /* text section */
+
+ text_sec = find_elf_section(shdr, ehdr.e_shnum, shstr, ".text");
+ if (!text_sec)
+ error("could not find .text section");
+ text = load_data(fd, text_sec->sh_offset, text_sec->sh_size);
+
+ /* find text relocations, if any */
+ nb_relocs = 0;
+ relocs = NULL;
+ reloc_sh_type = 0;
+ for(i = 0; i < ehdr.e_shnum; i++) {
+ sec = &shdr[i];
+ if ((sec->sh_type == SHT_REL || sec->sh_type == SHT_RELA) &&
+ sec->sh_info == (text_sec - shdr)) {
+ reloc_sh_type = sec->sh_type;
+ relocs = load_data(fd, sec->sh_offset, sec->sh_size);
+ nb_relocs = sec->sh_size / sec->sh_entsize;
+ if (do_swap) {
+ if (sec->sh_type == SHT_REL) {
+ Elf32_Rel *rel = relocs;
+ for(j = 0, rel = relocs; j < nb_relocs; j++, rel++) {
+ swab32s(&rel->r_offset);
+ swab32s(&rel->r_info);
+ }
+ } else {
+ Elf32_Rela *rel = relocs;
+ for(j = 0, rel = relocs; j < nb_relocs; j++, rel++) {
+ swab32s(&rel->r_offset);
+ swab32s(&rel->r_info);
+ swab32s(&rel->r_addend);
+ }
+ }
+ }
+ break;
+ }
+ }
+
+ symtab_sec = find_elf_section(shdr, ehdr.e_shnum, shstr, ".symtab");
+ if (!symtab_sec)
+ error("could not find .symtab section");
+ strtab_sec = &shdr[symtab_sec->sh_link];
+
+ symtab = load_data(fd, symtab_sec->sh_offset, symtab_sec->sh_size);
+ strtab = load_data(fd, strtab_sec->sh_offset, strtab_sec->sh_size);
+
+ nb_syms = symtab_sec->sh_size / sizeof(Elf32_Sym);
+ if (do_swap) {
+ for(i = 0, sym = symtab; i < nb_syms; i++, sym++) {
+ swab32s(&sym->st_name);
+ swab32s(&sym->st_value);
+ swab32s(&sym->st_size);
+ swab16s(&sym->st_shndx);
+ }
+ }
+
+ switch(e_machine) {
+ case EM_386:
+ cpu_name = "i386";
+ break;
+ case EM_PPC:
+ cpu_name = "ppc";
+ break;
+ case EM_MIPS:
+ cpu_name = "mips";
+ break;
+ case EM_ARM:
+ cpu_name = "arm";
+ break;
+ case EM_SPARC:
+ cpu_name = "sparc";
+ break;
+ default:
+ error("unsupported CPU (e_machine=%d)", e_machine);
+ }
+
+ fprintf(outfile, "#include \"gen-%s.h\"\n\n", cpu_name);
+
+ for(i = 0, sym = symtab; i < nb_syms; i++, sym++) {
+ const char *name;
+ name = strtab + sym->st_name;
+ if (strstart(name, "op_", NULL) ||
+ strstart(name, "op1_", NULL) ||
+ strstart(name, "op2_", NULL) ||
+ strstart(name, "op3_", NULL)) {
+#if 0
+ printf("%4d: %s pos=0x%08x len=%d\n",
+ i, name, sym->st_value, sym->st_size);
+#endif
+ if (sym->st_shndx != (text_sec - shdr))
+ error("invalid section for opcode (0x%x)", sym->st_shndx);
+ gen_code(name, sym->st_value, sym->st_size, outfile,
+ text, relocs, nb_relocs, reloc_sh_type, symtab, strtab);
+ }
+ }
+
+ close(fd);
+ return 0;
+}
+
+void usage(void)
+{
+ printf("dyngen (c) 2003 Fabrice Bellard\n"
+ "usage: dyngen [-o outfile] objfile\n"
+ "Generate a dynamic code generator from an object file\n");
+ exit(1);
+}
+
+int main(int argc, char **argv)
+{
+ int c;
+ const char *filename, *outfilename;
+ FILE *outfile;
+
+ outfilename = "out.c";
+ for(;;) {
+ c = getopt(argc, argv, "ho:");
+ if (c == -1)
+ break;
+ switch(c) {
+ case 'h':
+ usage();
+ break;
+ case 'o':
+ outfilename = optarg;
+ break;
+ }
+ }
+ if (optind >= argc)
+ usage();
+ filename = argv[optind];
+ outfile = fopen(outfilename, "w");
+ if (!outfile)
+ error("could not open '%s'", outfilename);
+ load_elf(filename, outfile);
+ fclose(outfile);
+ return 0;
+}