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[oota-llvm.git] / include / llvm / System / Memory.h

diff --git a/include/llvm/System/Memory.h b/include/llvm/System/Memory.h
index d692b95c271f98fb7af12e1a3e0ff92d767b07a9..2dd36e8ab14796430dcea2173923c0c684142cd9 100644 (file)
--- a/include/llvm/System/Memory.h
+++ b/include/llvm/System/Memory.h
@@ -14,8 +14,8 @@
 #ifndef LLVM_SYSTEM_MEMORY_H
 #define LLVM_SYSTEM_MEMORY_H
 
+#include "llvm/System/DataTypes.h"
 #include <string>
-#include "llvm/System/IncludeFile.h"
 
 namespace llvm {
 namespace sys {
@@ -27,11 +27,13 @@ namespace sys {
   /// @brief Memory block abstraction.
   class MemoryBlock {
   public:
+    MemoryBlock() : Address(0), Size(0) { }
+    MemoryBlock(void *addr, size_t size) : Address(addr), Size(size) { }
     void *base() const { return Address; }
-    unsigned size() const { return Size; }
+    size_t size() const { return Size; }
   private:
     void *Address;    ///< Address of first byte of memory area
-    unsigned Size;    ///< Size, in bytes of the memory area
+    size_t Size;      ///< Size, in bytes of the memory area
     friend class Memory;
   };
 
@@ -40,50 +42,55 @@ namespace sys {
   /// @since 1.4
   /// @brief An abstraction for memory operations.
   class Memory {
-    /// @name Functions
-    /// @{
-    public:
-      /// This method allocates a block of Read/Write/Execute memory that is
-      /// suitable for executing dynamically generated code (e.g. JIT). An
-      /// attempt to allocate \p NumBytes bytes of virtual memory is made.
-      /// \p NearBlock may point to an existing allocation in which case
-      /// an attempt is made to allocate more memory near the existing block.
-      ///
-      /// On success, this returns a non-null memory block, otherwise it returns
-      /// a null memory block and fills in *ErrMsg.
-      /// 
-      /// @brief Allocate Read/Write/Execute memory.
-      static MemoryBlock AllocateRWX(unsigned NumBytes,
-                                     const MemoryBlock *NearBlock,
-                                     std::string *ErrMsg = 0);
+  public:
+    /// This method allocates a block of Read/Write/Execute memory that is
+    /// suitable for executing dynamically generated code (e.g. JIT). An
+    /// attempt to allocate \p NumBytes bytes of virtual memory is made.
+    /// \p NearBlock may point to an existing allocation in which case
+    /// an attempt is made to allocate more memory near the existing block.
+    ///
+    /// On success, this returns a non-null memory block, otherwise it returns
+    /// a null memory block and fills in *ErrMsg.
+    /// 
+    /// @brief Allocate Read/Write/Execute memory.
+    static MemoryBlock AllocateRWX(size_t NumBytes,
+                                   const MemoryBlock *NearBlock,
+                                   std::string *ErrMsg = 0);
+
+    /// This method releases a block of Read/Write/Execute memory that was
+    /// allocated with the AllocateRWX method. It should not be used to
+    /// release any memory block allocated any other way.
+    ///
+    /// On success, this returns false, otherwise it returns true and fills
+    /// in *ErrMsg.
+    /// @brief Release Read/Write/Execute memory.
+    static bool ReleaseRWX(MemoryBlock &block, std::string *ErrMsg = 0);
+    
+    
+    /// InvalidateInstructionCache - Before the JIT can run a block of code
+    /// that has been emitted it must invalidate the instruction cache on some
+    /// platforms.
+    static void InvalidateInstructionCache(const void *Addr, size_t Len);
+
+    /// setExecutable - Before the JIT can run a block of code, it has to be
+    /// given read and executable privilege. Return true if it is already r-x
+    /// or the system is able to change its previlege.
+    static bool setExecutable (MemoryBlock &M, std::string *ErrMsg = 0);
 
-      /// This method allocates a block of Read/Write memory.  This memory
-      /// needs to have executable permissions set before it can be used
-      /// to execute JIT'ed code.
-      ///
-      /// On success, this returns a non-null memory block, otherwise it returns
-      /// a null memory block and fills in *ErrMsg.
-      /// 
-      /// @brief Allocate Read/Write/Execute memory.
-      static MemoryBlock AllocateRW(unsigned NumBytes,
-                                    const MemoryBlock *NearBlock,
-                                    std::string *ErrMsg = 0);
+    /// setWritable - When adding to a block of code, the JIT may need
+    /// to mark a block of code as RW since the protections are on page
+    /// boundaries, and the JIT internal allocations are not page aligned.
+    static bool setWritable (MemoryBlock &M, std::string *ErrMsg = 0);
 
-      /// This method releases a block of Read/Write/Execute memory that was
-      /// allocated with the AllocateRWX method. It should not be used to
-      /// release any memory block allocated any other way.
-      ///
-      /// On success, this returns false, otherwise it returns true and fills
-      /// in *ErrMsg.
-      /// @throws std::string if an error occurred.
-      /// @brief Release Read/Write/Execute memory.
-      static bool ReleaseRWX(MemoryBlock &block, std::string *ErrMsg = 0);
-      
-    /// @}
+    /// setRangeExecutable - Mark the page containing a range of addresses 
+    /// as executable.
+    static bool setRangeExecutable(const void *Addr, size_t Size);
+
+    /// setRangeWritable - Mark the page containing a range of addresses 
+    /// as writable.
+    static bool setRangeWritable(const void *Addr, size_t Size);
   };
 }
 }
 
-FORCE_DEFINING_FILE_TO_BE_LINKED(SystemMemory)
-
 #endif