-static int verify_code_arm64(const void *source, const void *copy, u_int size)
-{
- int ret = memcmp(source, copy, size);
- //printf("%s %p,%#x = %d\n", __func__, source, size, ret);
- return ret;
-}
-
-// this output is parsed by verify_dirty, get_bounds, isclean, get_clean_addr
-static void do_dirty_stub_base(u_int vaddr)
-{
- assert(slen <= MAXBLOCK);
- emit_loadlp_ofs(0, 0); // ldr x1, source
- emit_loadlp_ofs(0, 1); // ldr x2, copy
- emit_movz(slen*4, 2);
- emit_far_call(verify_code_arm64);
- void *jmp = out;
- emit_cbz(0, 0);
- emit_movz(vaddr & 0xffff, 0);
- emit_movk_lsl16(vaddr >> 16, 0);
- emit_far_call(get_addr);
- emit_jmpreg(0);
- set_jump_target(jmp, out);
-}
-
-static void assert_dirty_stub(const u_int *ptr)
-{
- assert((ptr[0] & 0xff00001f) == 0x58000000); // ldr x0, source
- assert((ptr[1] & 0xff00001f) == 0x58000001); // ldr x1, copy
- assert((ptr[2] & 0xffe0001f) == 0x52800002); // movz w2, #slen*4
- assert( ptr[8] == 0xd61f0000); // br x0
-}
-
-static void set_loadlp(u_int *loadl, void *lit)
-{
- uintptr_t ofs = (u_char *)lit - (u_char *)loadl;
- assert((*loadl & ~0x1f) == 0x58000000);
- assert((ofs & 3) == 0);
- assert(ofs < 0x100000);
- *loadl |= (ofs >> 2) << 5;
-}
-
-static void do_dirty_stub_emit_literals(u_int *loadlps)
-{
- set_loadlp(&loadlps[0], out);
- output_w64((uintptr_t)source);
- set_loadlp(&loadlps[1], out);
- output_w64((uintptr_t)copy);
-}
-
-static void *do_dirty_stub(int i)
-{
- assem_debug("do_dirty_stub %x\n",start+i*4);
- u_int *loadlps = (void *)out;
- do_dirty_stub_base(start + i*4);
- void *entry = out;
- load_regs_entry(i);
- if (entry == out)
- entry = instr_addr[i];
- emit_jmp(instr_addr[i]);
- do_dirty_stub_emit_literals(loadlps);
- return entry;
-}
-
-static void do_dirty_stub_ds(void)
-{
- u_int *loadlps = (void *)out;
- do_dirty_stub_base(start + 1);
- void *lit_jumpover = out;
- emit_jmp(out + 8*2);
- do_dirty_stub_emit_literals(loadlps);
- set_jump_target(lit_jumpover, out);
-}
-
-static uint64_t get_from_ldr_literal(const u_int *i)
-{
- signed int ofs;
- assert((i[0] & 0xff000000) == 0x58000000);
- ofs = i[0] << 8;
- ofs >>= 5+8;
- return *(uint64_t *)(i + ofs);
-}
-
-static uint64_t get_from_movz(const u_int *i)
-{
- assert((i[0] & 0x7fe00000) == 0x52800000);
- return (i[0] >> 5) & 0xffff;
-}
-
-// Find the "clean" entry point from a "dirty" entry point
-// by skipping past the call to verify_code
-static void *get_clean_addr(u_int *addr)
-{
- assert_dirty_stub(addr);
- return addr + 9;
-}
-
-static int verify_dirty(const u_int *ptr)
-{
- const void *source, *copy;
- u_int len;
- assert_dirty_stub(ptr);
- source = (void *)get_from_ldr_literal(&ptr[0]); // ldr x1, source
- copy = (void *)get_from_ldr_literal(&ptr[1]); // ldr x1, copy
- len = get_from_movz(&ptr[2]); // movz w3, #slen*4
- return !memcmp(source, copy, len);
-}
-
-static int isclean(void *addr)
-{
- const u_int *ptr = addr;
- if ((*ptr >> 24) == 0x58) { // the only place ldr (literal) is used
- assert_dirty_stub(ptr);
- return 0;
- }
- return 1;
-}
-
-// get source that block at addr was compiled from (host pointers)
-static void get_bounds(void *addr, u_char **start, u_char **end)
-{
- const u_int *ptr = addr;
- assert_dirty_stub(ptr);
- *start = (u_char *)get_from_ldr_literal(&ptr[0]); // ldr x1, source
- *end = *start + get_from_movz(&ptr[2]); // movz w3, #slen*4
-}
-