Added tests for bug detection on locals

runtime/szrt_asan.c

 //===- subzero/runtime/szrt_asan.c - AddressSanitizer Runtime -----*- C -*-===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
@@ skipping 61 matching lines @@
   else
     printf("protected bad region\n");
 }
 
 void __asan_check(char *ptr, int size) {
   printf("check %d bytes at %p\n", size, ptr);
   char *end = ptr + size;
   for (; ptr < end; ++ptr) {
     char shadow = *(char *)MEM2SHADOW(ptr);
     printf("checking %p with shadow %d\n", ptr, shadow);
-    assert(shadow == 0 || (shadow > 0 && SHADOW_OFFSET(ptr) <= shadow));
+    if (shadow != 0 && (shadow < 0 || SHADOW_OFFSET(ptr) > shadow)) {
+      fprintf(stderr, "Illegal access of %d bytes at %p\n", size, ptr);
+      abort();
+    }
   }
 }
 
 void *__asan_malloc(size_t size) {
   printf("malloc() called with size %d\n", size);
   size_t padding =
       (IS_SHADOW_ALIGNED(size)) ? 0 : SHADOW_SCALE - SHADOW_OFFSET(size);
   size_t rz_left_size = RZ_SIZE;
   size_t rz_right_size = RZ_SIZE + padding;
   void *rz_left;
@@ skipping 46 matching lines @@
   assert(size < 2 * RZ_SIZE);
   printf("unpoison %d bytes at %p: %p - %p\n", size, ptr, MEM2SHADOW(ptr),
          MEM2SHADOW(end));
   *(char *)MEM2SHADOW(ptr) = 0;
   ptr += SHADOW_OFFSET(size);
   assert(IS_SHADOW_ALIGNED(ptr));
   for (; ptr != end; ptr += SHADOW_SCALE) {
     *(char *)MEM2SHADOW(ptr) = 0;
   }
 }