Rename LineProfiling to GCOVProfiling to more accurately represent what it

does. Also mostly implement it. Still a work-in-progress, but generates legal
output on crafted test cases.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129630 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 104 insertions, 0 deletions

diff --git a/runtime/libprofile/GCDAProfiling.c b/runtime/libprofile/GCDAProfiling.c
new file mode 100644
index 0000000000..ee48ab5b6b
--- /dev/null
+++ b/runtime/libprofile/GCDAProfiling.c
@@ -0,0 +1,104 @@
+/*===- GCDAProfiling.c - Support library for GCDA file emission -----------===*\
+|*
+|*                     The LLVM Compiler Infrastructure
+|*
+|* This file is distributed under the University of Illinois Open Source
+|* License. See LICENSE.TXT for details.
+|* 
+|*===----------------------------------------------------------------------===*|
+|* 
+|* This file implements the call back routines for the gcov profiling
+|* instrumentation pass. Link against this library when running code through
+|* the -insert-gcov-profiling LLVM pass.
+|*
+|* We emit files in a corrupt version of GCOV's "gcda" file format. These files
+|* are only close enough that LCOV will happily parse them. Anything that lcov
+|* ignores is missing.
+|*
+\*===----------------------------------------------------------------------===*/
+
+#include "llvm/Support/DataTypes.h"
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+// #define DEBUG_GCDAPROFILING
+
+/*
+ * --- GCOV file format I/O primitives ---
+ */
+
+static FILE *output_file = NULL;
+
+static void write_int32(uint32_t i) {
+  fwrite(&i, 4, 1, output_file);
+}
+
+static void write_int64(uint64_t i) {
+  uint32_t lo, hi;
+  lo = i & 0x00000000ffffffff;
+  hi = i & 0xffffffff00000000;
+
+  write_int32(lo);
+  write_int32(hi);
+}
+
+/*
+ * --- LLVM line counter API ---
+ */
+
+/* A file in this case is a translation unit. Each .o file built with line
+ * profiling enabled will emit to a different file. Only one file may be
+ * started at a time.
+ */
+void llvm_gcda_start_file(const char *filename) {
+  output_file = fopen(filename, "w+");
+
+  /* gcda file, version 404*, stamp LLVM. */
+  fwrite("adcg*404MVLL", 12, 1, output_file);
+
+#ifdef DEBUG_GCDAPROFILING
+  printf("[%s]\n", filename);
+#endif
+}
+
+void llvm_gcda_emit_function(uint32_t ident) {
+#ifdef DEBUG_GCDAPROFILING
+  printf("function id=%x\n", ident);
+#endif
+
+  /* function tag */  
+  fwrite("\0\0\0\1", 4, 1, output_file);
+  write_int32(2);
+  write_int32(ident);
+  write_int32(0);
+}
+
+void llvm_gcda_emit_arcs(uint32_t num_counters, uint64_t *counters) {
+  uint32_t i;
+  /* counter #1 (arcs) tag */
+  fwrite("\0\0\xa1\1", 4, 1, output_file);
+  write_int32(num_counters * 2);
+  for (i = 0; i < num_counters; ++i) {
+    write_int64(counters[i]);
+  }
+
+#ifdef DEBUG_GCDAPROFILING
+  printf("  %u arcs\n", num_counters);
+  for (i = 0; i < num_counters; ++i) {
+    printf("  %llu\n", (unsigned long long)counters[i]);
+  }
+#endif
+}
+
+void llvm_gcda_end_file() {
+  /* Write out EOF record. */
+  fwrite("\0\0\0\0\0\0\0\0", 8, 1, output_file);
+  fclose(output_file);
+  output_file = NULL;
+
+#ifdef DEBUG_GCDAPROFILING
+  printf("-----\n");
+#endif
+}