Design a method to select predicate branches based on exploration counts

[c11tester.git] / mymemory.cc

diff --git a/mymemory.cc b/mymemory.cc
index 44985fa3aebc0d3fc32f97c0606b3c7ef11154a8..1f8b616020e481e795fd36f74bfa1d2ab56722cc 100644 (file)
--- a/mymemory.cc
+++ b/mymemory.cc
@@ -1,3 +1,4 @@
+
 #include <stdlib.h>
 #include <stdio.h>
 #include <dlfcn.h>
@@ -8,6 +9,8 @@
 #include "mymemory.h"
 #include "snapshot.h"
 #include "common.h"
+#include "threads-model.h"
+#include "model.h"
 
 #define REQUESTS_BEFORE_ALLOC 1024
 
@@ -68,6 +71,31 @@ void *model_malloc(size_t size)
 #endif
 }
 
+/** Non-snapshotting malloc for our use. */
+void *model_realloc(void *ptr, size_t size)
+{
+#if USE_MPROTECT_SNAPSHOT
+       static void *(*reallocp)(void *ptr, size_t size) = NULL;
+       char *error;
+       void *newptr;
+
+       /* get address of libc malloc */
+       if (!reallocp) {
+               reallocp = (void * (*)(size_t))dlsym(RTLD_NEXT, "realloc");
+               if ((error = dlerror()) != NULL) {
+                       fputs(error, stderr);
+                       exit(EXIT_FAILURE);
+               }
+       }
+       newptr = reallocp(ptr, size);
+       return newptr;
+#else
+       if (!sStaticSpace)
+               sStaticSpace = create_shared_mspace();
+       return mspace_realloc(sStaticSpace, ptr, size);
+#endif
+}
+
 /** @brief Snapshotting malloc, for use by model-checker (not user progs) */
 void * snapshot_malloc(size_t size)
 {
@@ -122,7 +150,7 @@ void model_free(void *ptr)
 /** Bootstrap allocation. Problem is that the dynamic linker calls require
  *  calloc to work and calloc requires the dynamic linker to work. */
 
-#define BOOTSTRAPBYTES 4096
+#define BOOTSTRAPBYTES 131072
 char bootstrapmemory[BOOTSTRAPBYTES];
 size_t offset = 0;
 
@@ -132,7 +160,7 @@ void * HandleEarlyAllocationRequest(size_t sz)
        sz = (sz + 7) & ~7;
 
        if (sz > (BOOTSTRAPBYTES-offset)) {
-               model_print("OUT OF BOOTSTRAP MEMORY\n");
+               model_print("OUT OF BOOTSTRAP MEMORY.  Increase the size of BOOTSTRAPBYTES in mymemory.cc\n");
                exit(EXIT_FAILURE);
        }
 
@@ -155,13 +183,31 @@ static bool DontFree(void *ptr)
        return (ptr >= (&bootstrapmemory[0]) && ptr < (&bootstrapmemory[BOOTSTRAPBYTES]));
 }
 
-/** @brief Snapshotting malloc implementation for user programs */
+/**
+ * @brief The allocator function for "user" allocation
+ *
+ * Should only be used for allocations which will not disturb the allocation
+ * patterns of a user thread.
+ */
+static void * user_malloc(size_t size)
+{
+       void *tmp = mspace_malloc(user_snapshot_space, size);
+       ASSERT(tmp);
+       return tmp;
+}
+
+/**
+ * @brief Snapshotting malloc implementation for user programs
+ *
+ * Do NOT call this function from a model-checker context. Doing so may disrupt
+ * the allocation patterns of a user thread.
+ */
 void *malloc(size_t size)
 {
        if (user_snapshot_space) {
-               void *tmp = mspace_malloc(user_snapshot_space, size);
-               ASSERT(tmp);
-               return tmp;
+               /* Only perform user allocations from user context */
+               ASSERT(!model || thread_current());
+               return user_malloc(size);
        } else
                return HandleEarlyAllocationRequest(size);
 }
@@ -169,8 +215,9 @@ void *malloc(size_t size)
 /** @brief Snapshotting free implementation for user programs */
 void free(void * ptr)
 {
-       if (!DontFree(ptr))
+       if (!DontFree(ptr)) {
                mspace_free(user_snapshot_space, ptr);
+       }
 }
 
 /** @brief Snapshotting realloc implementation for user programs */
@@ -195,6 +242,18 @@ void * calloc(size_t num, size_t size)
        }
 }
 
+/** @brief Snapshotting allocation function for use by the Thread class only */
+void * Thread_malloc(size_t size)
+{
+       return user_malloc(size);
+}
+
+/** @brief Snapshotting free function for use by the Thread class only */
+void Thread_free(void *ptr)
+{
+       free(ptr);
+}
+
 /** @brief Snapshotting new operator for user programs */
 void * operator new(size_t size) throw(std::bad_alloc)
 {
@@ -218,4 +277,19 @@ void operator delete[](void *p, size_t size)
 {
        free(p);
 }
-#endif /* USE_MPROTECT_SNAPSHOT */
+
+#else  /* !USE_MPROTECT_SNAPSHOT */
+
+/** @brief Snapshotting allocation function for use by the Thread class only */
+void * Thread_malloc(size_t size)
+{
+       return snapshot_malloc(size);
+}
+
+/** @brief Snapshotting free function for use by the Thread class only */
+void Thread_free(void *ptr)
+{
+       snapshot_free(ptr);
+}
+
+#endif /* !USE_MPROTECT_SNAPSHOT */