mirrors/cosmopolitan
1
0
Fork 0
mirror of https://github.com/jart/cosmopolitan.git synced 2025-05-28 08:12:28 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 1

Support thread local storage

Browse source
This commit is contained in:
Justine Tunney 2022-05-16 13:20:08 -07:00
parent 91ee2b19d4
commit 55de4ca6b5
197 changed files with 1483 additions and 874 deletions
Download patch file Download diff file Expand all files Collapse all files

59
libc/runtime/getinstructionlengths.c Normal file
View file

@ -0,0 +1,59 @@
/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2022 Justine Alexandra Roberts Tunney │
│ │
│ Permission to use, copy, modify, and/or distribute this software for │
│ any purpose with or without fee is hereby granted, provided that the │
│ above copyright notice and this permission notice appear in all copies. │
│ │
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
│ PERFORMANCE OF THIS SOFTWARE. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/calls/calls.h"
#include "libc/macros.internal.h"
#include "libc/runtime/runtime.h"
#include "libc/sysv/consts/map.h"
#include "libc/sysv/consts/prot.h"
#include "third_party/xed/x86.h"
/**
* Returns lengths of x86 ops in binary.
*
* The first decoded instruction is at `_ereal`. Lengths can be 1 to 15
* bytes. Each byte in the return value is in that range, and the array
* is NUL terminated. The returned memory is memoized, since this costs
* some time. For example, for a 10mb Python binary, it takes 20 millis
* so the basic idea is is you can use this output multiple times which
* is a faster way to iterate over the binary than calling Xed.
*
* @return nul-terminated length array on success, or null
*/
privileged unsigned char *GetInstructionLengths(void) {
static bool once;
int i, n, err, len, rem;
static unsigned char *res;
struct XedDecodedInst xedd;
unsigned char *p, *mem, *code;
if (!once) {
if ((mem = mmap(0, ROUNDUP(__privileged_addr - _ereal + 1, FRAMESIZE),
PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1,
0)) != MAP_FAILED) {
for (p = mem, code = _ereal; code < __privileged_addr; code += len) {
rem = __privileged_addr - code;
xed_decoded_inst_zero_set_mode(&xedd, XED_MACHINE_MODE_LONG_64);
err = xed_instruction_length_decode(&xedd, code, rem);
*p++ = len = !err ? xedd.length : 1;
}
res = mem;
}
once = true;
}
return res;
}