Merge System into Support.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120298 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 151 insertions, 0 deletions

diff --git a/lib/Support/Unix/Memory.inc b/lib/Support/Unix/Memory.inc
new file mode 100644
index 0000000000..4312d67183
--- /dev/null
+++ b/lib/Support/Unix/Memory.inc
@@ -0,0 +1,151 @@
+//===- Unix/Memory.cpp - Generic UNIX System Configuration ------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines some functions for various memory management utilities.
+//
+//===----------------------------------------------------------------------===//
+
+#include "Unix.h"
+#include "llvm/Support/DataTypes.h"
+#include "llvm/Support/Process.h"
+
+#ifdef HAVE_SYS_MMAN_H
+#include <sys/mman.h>
+#endif
+
+#ifdef __APPLE__
+#include <mach/mach.h>
+#endif
+
+/// AllocateRWX - Allocate a slab of memory with read/write/execute
+/// permissions.  This is typically used for JIT applications where we want
+/// to emit code to the memory then jump to it.  Getting this type of memory
+/// is very OS specific.
+///
+llvm::sys::MemoryBlock
+llvm::sys::Memory::AllocateRWX(size_t NumBytes, const MemoryBlock* NearBlock,
+                               std::string *ErrMsg) {
+  if (NumBytes == 0) return MemoryBlock();
+
+  size_t pageSize = Process::GetPageSize();
+  size_t NumPages = (NumBytes+pageSize-1)/pageSize;
+
+  int fd = -1;
+#ifdef NEED_DEV_ZERO_FOR_MMAP
+  static int zero_fd = open("/dev/zero", O_RDWR);
+  if (zero_fd == -1) {
+    MakeErrMsg(ErrMsg, "Can't open /dev/zero device");
+    return MemoryBlock();
+  }
+  fd = zero_fd;
+#endif
+
+  int flags = MAP_PRIVATE |
+#ifdef HAVE_MMAP_ANONYMOUS
+  MAP_ANONYMOUS
+#else
+  MAP_ANON
+#endif
+  ;
+
+  void* start = NearBlock ? (unsigned char*)NearBlock->base() +
+                            NearBlock->size() : 0;
+
+#if defined(__APPLE__) && defined(__arm__)
+  void *pa = ::mmap(start, pageSize*NumPages, PROT_READ|PROT_EXEC,
+                    flags, fd, 0);
+#else
+  void *pa = ::mmap(start, pageSize*NumPages, PROT_READ|PROT_WRITE|PROT_EXEC,
+                    flags, fd, 0);
+#endif
+  if (pa == MAP_FAILED) {
+    if (NearBlock) //Try again without a near hint
+      return AllocateRWX(NumBytes, 0);
+
+    MakeErrMsg(ErrMsg, "Can't allocate RWX Memory");
+    return MemoryBlock();
+  }
+
+#if defined(__APPLE__) && defined(__arm__)
+  kern_return_t kr = vm_protect(mach_task_self(), (vm_address_t)pa,
+                                (vm_size_t)(pageSize*NumPages), 0,
+                                VM_PROT_READ | VM_PROT_EXECUTE | VM_PROT_COPY);
+  if (KERN_SUCCESS != kr) {
+    MakeErrMsg(ErrMsg, "vm_protect max RX failed");
+    return sys::MemoryBlock();
+  }
+
+  kr = vm_protect(mach_task_self(), (vm_address_t)pa,
+                  (vm_size_t)(pageSize*NumPages), 0,
+                  VM_PROT_READ | VM_PROT_WRITE);
+  if (KERN_SUCCESS != kr) {
+    MakeErrMsg(ErrMsg, "vm_protect RW failed");
+    return sys::MemoryBlock();
+  }
+#endif
+
+  MemoryBlock result;
+  result.Address = pa;
+  result.Size = NumPages*pageSize;
+
+  return result;
+}
+
+bool llvm::sys::Memory::ReleaseRWX(MemoryBlock &M, std::string *ErrMsg) {
+  if (M.Address == 0 || M.Size == 0) return false;
+  if (0 != ::munmap(M.Address, M.Size))
+    return MakeErrMsg(ErrMsg, "Can't release RWX Memory");
+  return false;
+}
+
+bool llvm::sys::Memory::setWritable (MemoryBlock &M, std::string *ErrMsg) {
+#if defined(__APPLE__) && defined(__arm__)
+  if (M.Address == 0 || M.Size == 0) return false;
+  sys::Memory::InvalidateInstructionCache(M.Address, M.Size);
+  kern_return_t kr = vm_protect(mach_task_self(), (vm_address_t)M.Address,
+    (vm_size_t)M.Size, 0, VM_PROT_READ | VM_PROT_WRITE);
+  return KERN_SUCCESS == kr;
+#else
+  return true;
+#endif
+}
+
+bool llvm::sys::Memory::setExecutable (MemoryBlock &M, std::string *ErrMsg) {
+#if defined(__APPLE__) && defined(__arm__)
+  if (M.Address == 0 || M.Size == 0) return false;
+  sys::Memory::InvalidateInstructionCache(M.Address, M.Size);
+  kern_return_t kr = vm_protect(mach_task_self(), (vm_address_t)M.Address,
+    (vm_size_t)M.Size, 0, VM_PROT_READ | VM_PROT_EXECUTE | VM_PROT_COPY);
+  return KERN_SUCCESS == kr;
+#else
+  return false;
+#endif
+}
+
+bool llvm::sys::Memory::setRangeWritable(const void *Addr, size_t Size) {
+#if defined(__APPLE__) && defined(__arm__)
+  kern_return_t kr = vm_protect(mach_task_self(), (vm_address_t)Addr,
+                                (vm_size_t)Size, 0,
+                                VM_PROT_READ | VM_PROT_WRITE);
+  return KERN_SUCCESS == kr;
+#else
+  return true;
+#endif
+}
+
+bool llvm::sys::Memory::setRangeExecutable(const void *Addr, size_t Size) {
+#if defined(__APPLE__) && defined(__arm__)
+  kern_return_t kr = vm_protect(mach_task_self(), (vm_address_t)Addr,
+                                (vm_size_t)Size, 0,
+                                VM_PROT_READ | VM_PROT_EXECUTE | VM_PROT_COPY);
+  return KERN_SUCCESS == kr;
+#else
+  return true;
+#endif
+}