aboutsummaryrefslogtreecommitdiff
path: root/tools/llc/SRPCStreamer.cpp
blob: ae70a2482211bcddbbbb8d7e276fd9450aac1e0d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
//===-- SRPCStreamer.cpp - Stream bitcode over SRPC  ----------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
//
//
//===----------------------------------------------------------------------===//

#if defined(__native_client__) && defined(NACL_SRPC)
#define DEBUG_TYPE "bitcode-stream"
#include "SRPCStreamer.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include <errno.h>

using llvm::dbgs;

const size_t QueueStreamer::queuesize_limit_;

size_t QueueStreamer::GetBytes(unsigned char *buf, size_t len) {
  size_t total_copied = 0;
  pthread_mutex_lock(&Mutex);
  while (!Done && queueSize() < len - total_copied) {
    size_t size = queueSize();
    DEBUG(dbgs() << "QueueStreamer::GetBytes len " << len << " size " <<
          size << " << waiting\n");
    queueGet(buf + total_copied, size);
    total_copied += size;
    pthread_cond_signal(&Cond);
    pthread_cond_wait(&Cond, &Mutex);
  }
  // If this is the last partial chunk, adjust len such that the amount we
  // fetch will be just the remaining bytes.
  if (Done && queueSize() < len - total_copied) {
    len = queueSize() + total_copied;
  }
  queueGet(buf + total_copied, len - total_copied);
  pthread_cond_signal(&Cond);
  pthread_mutex_unlock(&Mutex);
  return len;
}

size_t QueueStreamer::PutBytes(unsigned char *buf, size_t len) {
  size_t total_copied = 0;
  pthread_mutex_lock(&Mutex);
  while (capacityRemaining() < len - total_copied) {
    if (Bytes.size() * 2 > queuesize_limit_) {
      size_t space = capacityRemaining();
      queuePut(buf + total_copied, space);
      total_copied += space;
      pthread_cond_signal(&Cond);
      pthread_cond_wait(&Cond, &Mutex);
    } else {
      queueResize();
    }
  }
  queuePut(buf + total_copied, len - total_copied);
  pthread_cond_signal(&Cond);
  pthread_mutex_unlock(&Mutex);
  return len;
}

void QueueStreamer::SetDone() {
  // Still need the lock to avoid signaling between the check and
  // the wait in GetBytes.
  pthread_mutex_lock(&Mutex);
  Done = true;
  pthread_cond_signal(&Cond);
  pthread_mutex_unlock(&Mutex);
}

// Double the size of the queue. Called with Mutex to protect Cons/Prod/Bytes.
void QueueStreamer::queueResize() {
  int leftover = Bytes.size() - Cons;
  DEBUG(dbgs() << "resizing to " << Bytes.size() * 2 << " " << leftover << " "
        << Prod << " " << Cons << "\n");
  Bytes.resize(Bytes.size() * 2);
  if (Cons > Prod) {
    // There are unread bytes left between Cons and the previous end of the
    // buffer. Move them to the new end of the buffer.
    memmove(&Bytes[Bytes.size() - leftover], &Bytes[Cons], leftover);
    Cons = Bytes.size() - leftover;
  }
}

// Called with Mutex held to protect Cons, Prod, and Bytes
void QueueStreamer::queuePut(unsigned char *buf, size_t len) {
  size_t EndSpace = std::min(len, Bytes.size() - Prod);
  DEBUG(dbgs() << "put, len " << len << " Endspace " << EndSpace << " p " <<
        Prod << " c " << Cons << "\n");
  // Copy up to the end of the buffer
  memcpy(&Bytes[Prod], buf, EndSpace);
  // Wrap around if necessary
  memcpy(&Bytes[0], buf + EndSpace, len - EndSpace);
  Prod = (Prod + len) % Bytes.size();
}

// Called with Mutex held to protect Cons, Prod, and Bytes
void QueueStreamer::queueGet(unsigned char *buf, size_t len) {
  assert(len <= queueSize());
  size_t EndSpace = std::min(len, Bytes.size() - Cons);
  DEBUG(dbgs() << "get, len " << len << " Endspace " << EndSpace << " p " <<
        Prod << " c " << Cons << "\n");
  // Copy up to the end of the buffer
  memcpy(buf, &Bytes[Cons], EndSpace);
  // Wrap around if necessary
  memcpy(buf + EndSpace, &Bytes[0], len - EndSpace);
  Cons = (Cons + len) % Bytes.size();
}

llvm::DataStreamer *SRPCStreamer::init(void *(*Callback)(void *), void *arg,
                                       std::string *ErrMsg) {
  int err = pthread_create(&CompileThread, NULL, Callback, arg);
  if (err) {
    if (ErrMsg) *ErrMsg = std::string(strerror(errno));
    return NULL;
  }
  return &Q;
}

size_t SRPCStreamer::gotChunk(unsigned char *bytes, size_t len) {
  if (Error) return 0;
  return Q.PutBytes(bytes, len);
}

int SRPCStreamer::streamEnd(std::string *ErrMsg) {
  Q.SetDone();
  int err = pthread_join(CompileThread, NULL);
  if (err) {
    if (ErrMsg) *ErrMsg = std::string(strerror(errno));
    return err;
  }
  if (Error && ErrMsg) *ErrMsg = std::string("compile failed.");
  return Error;
}

#endif