/*

 * IR - Lightweight JIT Compilation Framework

 * (Linux perf interface)

 * Copyright (C) 2022 Zend by Perforce.

 * Authors: Dmitry Stogov <dmitry@php.net>

 *

 * 1) Profile using perf-<pid>.map

 * perf record ./prog

 * perf report

 *

 * 2) Profile using jit-<pid>.dump

 * perf record -k 1 ./prog

 * perf inject -j -i perf.data -o perf.data.jitted

 * perf report -i perf.data.jitted

 */

#ifndef _GNU_SOURCE

# define _GNU_SOURCE

#endif

#include <stdio.h>

#include <unistd.h>

#include <time.h>

#include <sys/mman.h>

#include <sys/types.h>

#include <sys/stat.h>

#include <fcntl.h>

#include <string.h>

# include <limits.h>

#if defined(__linux__)

#include <sys/syscall.h>

#elif defined(__APPLE__)

# include <pthread.h>

#elif defined(__FreeBSD__)

# include <sys/thr.h>

# include <sys/sysctl.h>

#elif defined(__NetBSD__)

# include <lwp.h>

#elif defined(__DragonFly__)

# include <sys/lwp.h>

# include <sys/sysctl.h>

#elif defined(__sun)

// avoiding thread.h inclusion as it conflicts with vtunes types.

extern unsigned int thr_self(void);

#elif defined(__HAIKU__)

#include <FindDirectory.h>

#endif

#include "ir.h"

#include "ir_elf.h"

#define IR_PERF_JITDUMP_HEADER_MAGIC   0x4A695444

#define IR_PERF_JITDUMP_HEADER_VERSION 1

#define IR_PERF_JITDUMP_RECORD_LOAD       0

#define IR_PERF_JITDUMP_RECORD_MOVE       1

#define IR_PERF_JITDUMP_RECORD_DEBUG_INFO 2

#define IR_PERF_JITDUMP_RECORD_CLOSE      3

#define IR_PERF_JITDUMP_UNWINDING_UNFO    4

#define ALIGN8(size)   (((size) + 7) & ~7)

#define PADDING8(size) (ALIGN8(size) - (size))

typedef struct ir_perf_jitdump_header {

  uint32_t magic;

  uint32_t version;

  uint32_t size;

  uint32_t elf_mach_target;

  uint32_t reserved;

  uint32_t process_id;

  uint64_t time_stamp;

  uint64_t flags;

} ir_perf_jitdump_header;

typedef struct _ir_perf_jitdump_record {

  uint32_t event;

  uint32_t size;

  uint64_t time_stamp;

} ir_perf_jitdump_record;

typedef struct _ir_perf_jitdump_load_record {

  ir_perf_jitdump_record hdr;

  uint32_t process_id;

  uint32_t thread_id;

  uint64_t vma;

  uint64_t code_address;

  uint64_t code_size;

  uint64_t code_id;

} ir_perf_jitdump_load_record;

static int   jitdump_fd  = -1;

static void *jitdump_mem = MAP_FAILED;

static uint64_t ir_perf_timestamp(void)

{

  struct timespec ts;

  if (clock_gettime(CLOCK_MONOTONIC, &ts) != 0) {

    return 0;

  }

  return ((uint64_t)ts.tv_sec * 1000000000) + ts.tv_nsec;

}

int ir_perf_jitdump_open(void)

{

  char filename[64];

  int fd, ret;

  ir_elf_header elf_hdr;

  ir_perf_jitdump_header jit_hdr;

  snprintf(filename, sizeof(filename), "/tmp/jit-%d.dump", getpid());

  if (!ir_perf_timestamp()) {

    return 0;

  }

#if defined(__linux__)

  fd = open("/proc/self/exe", O_RDONLY);

#elif defined(__NetBSD__)

  fd = open("/proc/curproc/exe", O_RDONLY);

#elif defined(__FreeBSD__) || defined(__DragonFly__)

  char path[PATH_MAX];

  size_t pathlen = sizeof(path);

  int mib[4] = {CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1};

  if (sysctl(mib, 4, path, &pathlen, NULL, 0) == -1) {

    return 0;

  }

  fd = open(path, O_RDONLY);

#elif defined(__sun)

  fd = open("/proc/self/path/a.out", O_RDONLY);

#elif defined(__HAIKU__)

  char path[PATH_MAX];

  if (find_path(B_APP_IMAGE_SYMBOL, B_FIND_PATH_IMAGE_PATH,

    NULL, path, sizeof(path)) != B_OK) {

    return 0;

  }

  fd = open(path, O_RDONLY);

#else

  fd = -1;

#endif

  if (fd < 0) {

    return 0;

  }

  ret = read(fd, &elf_hdr, sizeof(elf_hdr));

  close(fd);

  if (ret != sizeof(elf_hdr) ||

      elf_hdr.emagic[0] != 0x7f ||

      elf_hdr.emagic[1] != 'E' ||

      elf_hdr.emagic[2] != 'L' ||

      elf_hdr.emagic[3] != 'F') {

    return 0;

  }

  jitdump_fd = open(filename, O_CREAT | O_TRUNC | O_RDWR, 0666);

  if (jitdump_fd < 0) {

    return 0;

  }

  jitdump_mem = mmap(NULL,

      sysconf(_SC_PAGESIZE),

      PROT_READ|PROT_EXEC,

      MAP_PRIVATE, jitdump_fd, 0);

  if (jitdump_mem == MAP_FAILED) {

    close(jitdump_fd);

    jitdump_fd = -1;

    return 0;

  }

  memset(&jit_hdr, 0, sizeof(jit_hdr));

  jit_hdr.magic           = IR_PERF_JITDUMP_HEADER_MAGIC;

  jit_hdr.version         = IR_PERF_JITDUMP_HEADER_VERSION;

  jit_hdr.size            = sizeof(jit_hdr);

  jit_hdr.elf_mach_target = elf_hdr.machine;

  jit_hdr.process_id      = getpid();

  jit_hdr.time_stamp      = ir_perf_timestamp();

  jit_hdr.flags           = 0;

  if (write(jitdump_fd, &jit_hdr, sizeof(jit_hdr)) != sizeof(jit_hdr)) {

    return 0;

  }

  return 1;

}

int ir_perf_jitdump_close(void)

{

  int ret = 1;

  if (jitdump_fd >= 0) {

    ir_perf_jitdump_record rec;

    rec.event      = IR_PERF_JITDUMP_RECORD_CLOSE;

    rec.size       = sizeof(rec);

    rec.time_stamp = ir_perf_timestamp();

    if (write(jitdump_fd, &rec, sizeof(rec)) != sizeof(rec)) {

      ret = 0;

    }

    close(jitdump_fd);

    if (jitdump_mem != MAP_FAILED) {

      munmap(jitdump_mem, sysconf(_SC_PAGESIZE));

    }

  }

  return ret;

}

int ir_perf_jitdump_register(const char *name, const void *start, size_t size)

{

  if (jitdump_fd >= 0) {

    static uint64_t id = 1;

    ir_perf_jitdump_load_record rec;

    size_t len = strlen(name);

    uint32_t thread_id = 0;

#if defined(__linux__)

    thread_id = syscall(SYS_gettid);

#elif defined(__APPLE__)

    uint64_t thread_id_u64;

    pthread_threadid_np(NULL, &thread_id_u64);

    thread_id = (uint32_t) thread_id_u64;

#elif defined(__FreeBSD__)

    long tid;

    thr_self(&tid);

    thread_id = (uint32_t)tid;

#elif defined(__OpenBSD__)

    thread_id = getthrid();

#elif defined(__NetBSD__)

    thread_id = _lwp_self();

#elif defined(__DragonFly__)

    thread_id = lwp_gettid();

#elif defined(__sun)

    thread_id = thr_self();

#endif

    memset(&rec, 0, sizeof(rec));

    rec.hdr.event      = IR_PERF_JITDUMP_RECORD_LOAD;

    rec.hdr.size       = sizeof(rec) + len + 1 + size;

    rec.hdr.time_stamp = ir_perf_timestamp();

    rec.process_id     = getpid();

    rec.thread_id      = thread_id;

    rec.vma            = (uint64_t)(uintptr_t)start;

    rec.code_address   = (uint64_t)(uintptr_t)start;

    rec.code_size      = (uint64_t)size;

    rec.code_id        = id++;

    if (write(jitdump_fd, &rec, sizeof(rec)) != sizeof(rec)

     || write(jitdump_fd, name, len + 1) < 0

     || write(jitdump_fd, start, size) < 0) {

      return 0;

    }

  }

  return 1;

}

void ir_perf_map_register(const char *name, const void *start, size_t size)

{

  static FILE *fp = NULL;

  if (!fp) {

    char filename[64];

    snprintf(filename, sizeof(filename), "/tmp/perf-%d.map", getpid());

    fp = fopen(filename, "w");

    if (!fp) {

      return;

    }

      setlinebuf(fp);

  }

  fprintf(fp, "%zx %zx %s\n", (size_t)(uintptr_t)start, size, name);

}