blob: 8f4119c2c67d65a41b5cafbd6ffd15efdc808699 [file] [log] [blame]
/*===-- CommonProfiling.c - Profiling support library support -------------===*\
|*
|* The LLVM Compiler Infrastructure
|*
|* This file is distributed under the University of Illinois Open Source
|* License. See LICENSE.TXT for details.
|*
|*===----------------------------------------------------------------------===*|
|*
|* This file implements functions used by the various different types of
|* profiling implementations.
|*
\*===----------------------------------------------------------------------===*/
#include "Profiling.h"
#include <assert.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdio.h>
#include <string.h>
#if !defined(_MSC_VER) && !defined(__MINGW32__)
#include <unistd.h>
#else
#include <io.h>
#endif
#include <stdlib.h>
static char *SavedArgs = 0;
static unsigned SavedArgsLength = 0;
static const char *SavedEnvVar = 0;
static const char *OutputFilename = "llvmprof.out";
/* check_environment_variable - Check to see if the LLVMPROF_OUTPUT environment
* variable is set. If it is then save it and set OutputFilename.
*/
static void check_environment_variable(void) {
const char *EnvVar;
if (SavedEnvVar) return; /* Guarantee that we can't leak memory. */
if ((EnvVar = getenv("LLVMPROF_OUTPUT")) != NULL) {
/* The string that getenv returns is allowed to be statically allocated,
* which means it may be changed by future calls to getenv, so copy it.
*/
SavedEnvVar = strdup(EnvVar);
OutputFilename = SavedEnvVar;
}
}
/* save_arguments - Save argc and argv as passed into the program for the file
* we output.
* If either the LLVMPROF_OUTPUT environment variable or the -llvmprof-output
* command line argument are set then change OutputFilename to the provided
* value. The command line argument value overrides the environment variable.
*/
int save_arguments(int argc, const char **argv) {
unsigned Length, i;
if (!SavedEnvVar && !SavedArgs) check_environment_variable();
if (SavedArgs || !argv) return argc; /* This can be called multiple times */
/* Check to see if there are any arguments passed into the program for the
* profiler. If there are, strip them off and remember their settings.
*/
while (argc > 1 && !strncmp(argv[1], "-llvmprof-", 10)) {
/* Ok, we have an llvmprof argument. Remove it from the arg list and decide
* what to do with it.
*/
const char *Arg = argv[1];
memmove((char**)&argv[1], &argv[2], (argc-1)*sizeof(char*));
--argc;
if (!strcmp(Arg, "-llvmprof-output")) {
if (argc == 1)
puts("-llvmprof-output requires a filename argument!");
else {
OutputFilename = strdup(argv[1]);
if (SavedEnvVar) { free((void *)SavedEnvVar); SavedEnvVar = 0; }
memmove((char**)&argv[1], &argv[2], (argc-1)*sizeof(char*));
--argc;
}
} else {
printf("Unknown option to the profiler runtime: '%s' - ignored.\n", Arg);
}
}
for (Length = 0, i = 0; i != (unsigned)argc; ++i)
Length += strlen(argv[i])+1;
/* Defensively check for a zero length, even though this is unlikely
* to happen in practice. This avoids calling malloc() below with a
* size of 0.
*/
if (Length == 0) {
SavedArgs = 0;
SavedArgsLength = 0;
return argc;
}
SavedArgs = (char*)malloc(Length);
for (Length = 0, i = 0; i != (unsigned)argc; ++i) {
unsigned Len = strlen(argv[i]);
memcpy(SavedArgs+Length, argv[i], Len);
Length += Len;
SavedArgs[Length++] = ' ';
}
SavedArgsLength = Length;
return argc;
}
/*
* Retrieves the file descriptor for the profile file.
*/
int getOutFile() {
static int OutFile = -1;
/* If this is the first time this function is called, open the output file
* for appending, creating it if it does not already exist.
*/
if (OutFile == -1) {
OutFile = open(OutputFilename, O_CREAT | O_WRONLY, 0666);
lseek(OutFile, 0, SEEK_END); /* O_APPEND prevents seeking */
if (OutFile == -1) {
fprintf(stderr, "LLVM profiling runtime: while opening '%s': ",
OutputFilename);
perror("");
return(OutFile);
}
/* Output the command line arguments to the file. */
{
int PTy = ArgumentInfo;
int Zeros = 0;
if (write(OutFile, &PTy, sizeof(int)) < 0 ||
write(OutFile, &SavedArgsLength, sizeof(unsigned)) < 0 ||
write(OutFile, SavedArgs, SavedArgsLength) < 0 ) {
fprintf(stderr,"error: unable to write to output file.");
exit(0);
}
/* Pad out to a multiple of four bytes */
if (SavedArgsLength & 3) {
if (write(OutFile, &Zeros, 4-(SavedArgsLength&3)) < 0) {
fprintf(stderr,"error: unable to write to output file.");
exit(0);
}
}
}
}
return(OutFile);
}
/* write_profiling_data - Write a raw block of profiling counters out to the
* llvmprof.out file. Note that we allow programs to be instrumented with
* multiple different kinds of instrumentation. For this reason, this function
* may be called more than once.
*/
void write_profiling_data(enum ProfilingType PT, unsigned *Start,
unsigned NumElements) {
int PTy;
int outFile = getOutFile();
/* Write out this record! */
PTy = PT;
if( write(outFile, &PTy, sizeof(int)) < 0 ||
write(outFile, &NumElements, sizeof(unsigned)) < 0 ||
write(outFile, Start, NumElements*sizeof(unsigned)) < 0 ) {
fprintf(stderr,"error: unable to write to output file.");
exit(0);
}
}