aboutsummaryrefslogtreecommitdiff
path: root/include/llvm/Support/Memory.h
diff options
context:
space:
mode:
authorDerek Schuff <dschuff@chromium.org>2012-09-25 17:30:25 -0700
committerDerek Schuff <dschuff@chromium.org>2012-09-25 18:01:23 -0700
commita27c28b1427dc2082ab2b31efdbb25f9fde31b61 (patch)
tree6f3ff025f542ca3f66a1a01cbf239aeef7784511 /include/llvm/Support/Memory.h
parent0e15ffd8cb1ec642eddb96380660914ff2b007e1 (diff)
parentbc4021f31eaa97ee52655828da3e3de14a39e4a6 (diff)
Merge commit 'bc4021f31eaa97ee52655828da3e3de14a39e4a6'
Conflicts: lib/MC/MCAssembler.cpp lib/Target/ARM/ARMISelDAGToDAG.cpp lib/Target/Mips/MipsInstrFPU.td lib/Target/X86/MCTargetDesc/X86AsmBackend.cpp lib/Target/X86/X86ISelLowering.h
Diffstat (limited to 'include/llvm/Support/Memory.h')
-rw-r--r--include/llvm/Support/Memory.h65
1 files changed, 65 insertions, 0 deletions
diff --git a/include/llvm/Support/Memory.h b/include/llvm/Support/Memory.h
index 37890e7e4a..8227c84bff 100644
--- a/include/llvm/Support/Memory.h
+++ b/include/llvm/Support/Memory.h
@@ -15,6 +15,7 @@
#define LLVM_SYSTEM_MEMORY_H
#include "llvm/Support/DataTypes.h"
+#include "llvm/Support/system_error.h"
#include <string>
namespace llvm {
@@ -43,6 +44,70 @@ namespace sys {
/// @brief An abstraction for memory operations.
class Memory {
public:
+ enum ProtectionFlags {
+ MF_READ = 0x1000000,
+ MF_WRITE = 0x2000000,
+ MF_EXEC = 0x4000000
+ };
+
+ /// This method allocates a block of memory that is suitable for loading
+ /// 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.
+ /// The actual allocated address is not guaranteed to be near the requested
+ /// address.
+ /// \p Flags is used to set the initial protection flags for the block
+ /// of the memory.
+ /// \p EC [out] returns an object describing any error that occurs.
+ ///
+ /// This method may allocate more than the number of bytes requested. The
+ /// actual number of bytes allocated is indicated in the returned
+ /// MemoryBlock.
+ ///
+ /// The start of the allocated block must be aligned with the
+ /// system allocation granularity (64K on Windows, page size on Linux).
+ /// If the address following \p NearBlock is not so aligned, it will be
+ /// rounded up to the next allocation granularity boundary.
+ ///
+ /// \r a non-null MemoryBlock if the function was successful,
+ /// otherwise a null MemoryBlock is with \p EC describing the error.
+ ///
+ /// @brief Allocate mapped memory.
+ static MemoryBlock allocateMappedMemory(size_t NumBytes,
+ const MemoryBlock *const NearBlock,
+ unsigned Flags,
+ error_code &EC);
+
+ /// This method releases a block of memory that was allocated with the
+ /// allocateMappedMemory method. It should not be used to release any
+ /// memory block allocated any other way.
+ /// \p Block describes the memory to be released.
+ ///
+ /// \r error_success if the function was successful, or an error_code
+ /// describing the failure if an error occurred.
+ ///
+ /// @brief Release mapped memory.
+ static error_code releaseMappedMemory(MemoryBlock &Block);
+
+ /// This method sets the protection flags for a block of memory to the
+ /// state specified by /p Flags. The behavior is not specified if the
+ /// memory was not allocated using the allocateMappedMemory method.
+ /// \p Block describes the memory block to be protected.
+ /// \p Flags specifies the new protection state to be assigned to the block.
+ /// \p ErrMsg [out] returns a string describing any error that occured.
+ ///
+ /// If \p Flags is MF_WRITE, the actual behavior varies
+ /// with the operating system (i.e. MF_READWRITE on Windows) and the
+ /// target architecture (i.e. MF_WRITE -> MF_READWRITE on i386).
+ ///
+ /// \r error_success if the function was successful, or an error_code
+ /// describing the failure if an error occurred.
+ ///
+ /// @brief Set memory protection state.
+ static error_code protectMappedMemory(const MemoryBlock &Block,
+ unsigned Flags);
+
/// 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.