Create the parent directories to place the .gcda files in if they don't exist.

That's kinda weird because the .gcno files are supposed to already be there,
but libgcov does this and somehow Google has managed to depend on it.

llvm-svn: 130879

Author: nlewycky

llvm/runtime/libprofile/GCDAProfiling.c

@@ -24,6 +24,8 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
 
 /* #define DEBUG_GCDAPROFILING */
 
@@ -64,6 +66,21 @@ static char *mangle_filename(const char *orig_filename) {
   return filename;
 }
 
+static void recursive_mkdir(const char *filename) {
+  char *pathname;
+  int i, e;
+
+  for (i = 1, e = strlen(filename); i != e; ++i) {
+    if (filename[i] == '/') {
+      pathname = malloc(i + 1);
+      strncpy(pathname, filename, i);
+      pathname[i] = '\0';
+      mkdir(pathname, 0750);  /* some of these will fail, ignore it. */
+      free(pathname);
+    }
+  }
+}
+
 /*
  * --- LLVM line counter API ---
  */
@@ -75,6 +92,7 @@ static char *mangle_filename(const char *orig_filename) {
 void llvm_gcda_start_file(const char *orig_filename) {
   char *filename;
   filename = mangle_filename(orig_filename);
+  recursive_mkdir(filename);
   output_file = fopen(filename, "wb");
 
   /* gcda file, version 404*, stamp LLVM. */