Implementation of path profiling.
Modified patch by Adam Preuss.
This builds on the existing framework for block tracing, edge profiling and optimal edge profiling.
See -help-hidden for new flags.
For documentation, see the technical report "Implementation of Path Profiling..." in llvm.org/pubs.
llvm-svn: 124515
diff --git a/llvm/runtime/libprofile/CommonProfiling.c b/llvm/runtime/libprofile/CommonProfiling.c
index 8b27a25..1c1771c 100644
--- a/llvm/runtime/libprofile/CommonProfiling.c
+++ b/llvm/runtime/libprofile/CommonProfiling.c
@@ -2,17 +2,18 @@
|*
|* The LLVM Compiler Infrastructure
|*
-|* This file is distributed under the University of Illinois Open Source
-|* License. See LICENSE.TXT for details.
-|*
+|* 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>
@@ -74,26 +75,23 @@
}
-/* 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.
+/*
+ * Retrieves the file descriptor for the profile file.
*/
-void write_profiling_data(enum ProfilingType PT, unsigned *Start,
- unsigned NumElements) {
+int getOutFile() {
static int OutFile = -1;
- int PTy;
-
- /* 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 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 | O_APPEND, 0666);
+ 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;
+ return(OutFile);
}
/* Output the command line arguments to the file. */
@@ -108,10 +106,25 @@
write(OutFile, &Zeros, 4-(SavedArgsLength&3));
}
}
-
+ 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;
- write(OutFile, &PTy, sizeof(int));
- write(OutFile, &NumElements, sizeof(unsigned));
- write(OutFile, Start, NumElements*sizeof(unsigned));
+ 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);
+ }
}