lib/profile/InstrProfilingBuffer.c

   1 /*===- InstrProfilingBuffer.c - Write instrumentation to a memory buffer --===*\
   2 |*
   3 |*                     The LLVM Compiler Infrastructure
   4 |*
   5 |* This file is distributed under the University of Illinois Open Source
   6 |* License. See LICENSE.TXT for details.
   7 |*
   8 \*===----------------------------------------------------------------------===*/
   9
  10 #include "InstrProfiling.h"
  11 #include <string.h>
  12
  13 __attribute__((visibility("hidden")))
  14 uint64_t __llvm_profile_get_size_for_buffer(void) {
  15   /* Match logic in __llvm_profile_write_buffer(). */
  16   const uint64_t NamesSize = PROFILE_RANGE_SIZE(names) * sizeof(char);
  17   const uint64_t Padding = sizeof(uint64_t) - NamesSize % sizeof(uint64_t);
  18   return sizeof(uint64_t) * PROFILE_HEADER_SIZE +
  19      PROFILE_RANGE_SIZE(data) * sizeof(__llvm_profile_data) +
  20      PROFILE_RANGE_SIZE(counters) * sizeof(uint64_t) +
  21      NamesSize + Padding;
  22 }
  23
  24 __attribute__((visibility("hidden")))
  25 int __llvm_profile_write_buffer(char *Buffer) {
  26   /* Match logic in __llvm_profile_get_size_for_buffer().
  27    * Match logic in __llvm_profile_write_file().
  28    */
  29   const __llvm_profile_data *DataBegin = __llvm_profile_data_begin();
  30   const __llvm_profile_data *DataEnd = __llvm_profile_data_end();
  31   const uint64_t *CountersBegin = __llvm_profile_counters_begin();
  32   const uint64_t *CountersEnd   = __llvm_profile_counters_end();
  33   const char *NamesBegin = __llvm_profile_names_begin();
  34   const char *NamesEnd   = __llvm_profile_names_end();
  35
  36   /* Calculate size of sections. */
  37   const uint64_t DataSize = DataEnd - DataBegin;
  38   const uint64_t CountersSize = CountersEnd - CountersBegin;
  39   const uint64_t NamesSize = NamesEnd - NamesBegin;
  40   const uint64_t Padding = sizeof(uint64_t) - NamesSize % sizeof(uint64_t);
  41
  42   /* Enough zeroes for padding. */
  43   const char Zeroes[sizeof(uint64_t)] = {0};
  44
  45   /* Create the header. */
  46   uint64_t Header[PROFILE_HEADER_SIZE];
  47   Header[0] = __llvm_profile_get_magic();
  48   Header[1] = __llvm_profile_get_version();
  49   Header[2] = DataSize;
  50   Header[3] = CountersSize;
  51   Header[4] = NamesSize;
  52   Header[5] = (uintptr_t)CountersBegin;
  53   Header[6] = (uintptr_t)NamesBegin;
  54
  55   /* Write the data. */
  56 #define UPDATE_memcpy(Data, Size) \
  57   do {                            \
  58     memcpy(Buffer, Data, Size);   \
  59     Buffer += Size;               \
  60   } while (0)
  61   UPDATE_memcpy(Header,  PROFILE_HEADER_SIZE * sizeof(uint64_t));
  62   UPDATE_memcpy(DataBegin,     DataSize      * sizeof(__llvm_profile_data));
  63   UPDATE_memcpy(CountersBegin, CountersSize  * sizeof(uint64_t));
  64   UPDATE_memcpy(NamesBegin,    NamesSize     * sizeof(char));
  65   UPDATE_memcpy(Zeroes,        Padding       * sizeof(char));
  66 #undef UPDATE_memcpy
  67
  68   return 0;
  69 }