README: extra "from"

[cdsspec-compiler.git] / mymemory.cc

diff --git a/mymemory.cc b/mymemory.cc
index a15a13dd522bf54bb0b7e3c7fd49ff014467db56..9e05c369235dadb077b6d09b1cfb7b2ece92180f 100644 (file)
--- a/mymemory.cc
+++ b/mymemory.cc
@@ -7,8 +7,9 @@
 
 #include "mymemory.h"
 #include "snapshot.h"
-#include "snapshotimp.h"
 #include "common.h"
+#include "threads-model.h"
+#include "model.h"
 
 #define REQUESTS_BEFORE_ALLOC 1024
 
@@ -38,10 +39,8 @@ void *model_calloc(size_t count, size_t size)
        ptr = callocp(count, size);
        return ptr;
 #else
-       if (!snapshotrecord)
-               createSharedMemory();
        if (!sStaticSpace)
-               sStaticSpace = create_mspace_with_base((void *)(snapshotrecord->mSharedMemoryBase), SHARED_MEMORY_DEFAULT - sizeof(struct SnapShot), 1);
+               sStaticSpace = create_shared_mspace();
        return mspace_calloc(sStaticSpace, count, size);
 #endif
 }
@@ -65,10 +64,8 @@ void *model_malloc(size_t size)
        ptr = mallocp(size);
        return ptr;
 #else
-       if (!snapshotrecord)
-               createSharedMemory();
        if (!sStaticSpace)
-               sStaticSpace = create_mspace_with_base((void *)(snapshotrecord->mSharedMemoryBase), SHARED_MEMORY_DEFAULT - sizeof(struct SnapShot), 1);
+               sStaticSpace = create_shared_mspace();
        return mspace_malloc(sStaticSpace, size);
 #endif
 }
@@ -160,13 +157,31 @@ 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);
 }
@@ -200,6 +215,18 @@ 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)
 {
@@ -223,4 +250,19 @@ 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 malloc(size);
+}
+
+/** @brief Snapshotting free function for use by the Thread class only */
+void Thread_free(void *ptr)
+{
+       free(ptr);
+}
+
+#endif /* !USE_MPROTECT_SNAPSHOT */