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-rw-r--r--runtime/libprofile/BasicBlockTracing.c67
1 files changed, 67 insertions, 0 deletions
diff --git a/runtime/libprofile/BasicBlockTracing.c b/runtime/libprofile/BasicBlockTracing.c
new file mode 100644
index 0000000..0013633
--- /dev/null
+++ b/runtime/libprofile/BasicBlockTracing.c
@@ -0,0 +1,67 @@
+/*===-- BasicBlockTracing.c - Support library for basic block tracing -----===*\
+|*
+|* The LLVM Compiler Infrastructure
+|*
+|* This file was developed by the LLVM research group and is distributed under
+|* the University of Illinois Open Source License. See LICENSE.TXT for details.
+|*
+|*===----------------------------------------------------------------------===*|
+|*
+|* This file implements the call back routines for the basic block tracing
+|* instrumentation pass. This should be used with the -trace-basic-blocks
+|* LLVM pass.
+|*
+\*===----------------------------------------------------------------------===*/
+
+#include "Profiling.h"
+#include <stdlib.h>
+#include <stdio.h>
+
+static unsigned *ArrayStart, *ArrayEnd, *ArrayCursor;
+
+/* WriteAndFlushBBTraceData - write out the currently accumulated trace data
+ * and reset the cursor to point to the beginning of the buffer.
+ */
+static void WriteAndFlushBBTraceData () {
+ write_profiling_data(BBTrace, ArrayStart, (ArrayCursor - ArrayStart));
+ ArrayCursor = ArrayStart;
+}
+
+/* BBTraceAtExitHandler - When the program exits, just write out any remaining
+ * data and free the trace buffer.
+ */
+static void BBTraceAtExitHandler() {
+ WriteAndFlushBBTraceData ();
+ free (ArrayStart);
+}
+
+/* llvm_trace_basic_block - called upon hitting a new basic block. */
+void llvm_trace_basic_block (unsigned BBNum) {
+ *ArrayCursor++ = BBNum;
+ if (ArrayCursor == ArrayEnd)
+ WriteAndFlushBBTraceData ();
+}
+
+/* llvm_start_basic_block_tracing - This is the main entry point of the basic
+ * block tracing library. It is responsible for setting up the atexit
+ * handler and allocating the trace buffer.
+ */
+int llvm_start_basic_block_tracing(int argc, const char **argv,
+ unsigned *arrayStart, unsigned numElements) {
+ int Ret;
+ const unsigned BufferSize = 128 * 1024;
+ unsigned ArraySize;
+
+ Ret = save_arguments(argc, argv);
+
+ /* Allocate a buffer to contain BB tracing data */
+ ArraySize = BufferSize / sizeof (unsigned);
+ ArrayStart = malloc (ArraySize * sizeof (unsigned));
+ ArrayEnd = ArrayStart + ArraySize;
+ ArrayCursor = ArrayStart;
+
+ /* Set up the atexit handler. */
+ atexit (BBTraceAtExitHandler);
+
+ return Ret;
+}