Provide initial implementations of Memory and Process concepts for various

platforms.
Implement GetLLVMSuffix function for the Path concept.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16292 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 62 insertions, 0 deletions

diff --git a/lib/System/Linux/Memory.cpp b/lib/System/Linux/Memory.cpp
new file mode 100644
index 0000000000..1bc6fd98bb
--- /dev/null
+++ b/lib/System/Linux/Memory.cpp
@@ -0,0 +1,62 @@
+//===- Linux/Memory.cpp - Linux Memory Implementation -----*- C++ -*-===//
+// 
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by Reid Spencer and is distributed under the 
+// University of Illinois Open Source License. See LICENSE.TXT for details.
+// 
+//===----------------------------------------------------------------------===//
+//
+// This file provides the Linux specific implementation of various Memory
+// management utilities
+//
+//===----------------------------------------------------------------------===//
+
+// Include the generic unix implementation
+#include "../Unix/Memory.cpp"
+#include "llvm/System/Process.h"
+#include <sys/mman.h>
+
+namespace llvm {
+using namespace sys;
+
+//===----------------------------------------------------------------------===//
+//=== WARNING: Implementation here must contain only Linux specific code 
+//===          and must not be generic UNIX code (see ../Unix/Memory.cpp)
+//===----------------------------------------------------------------------===//
+
+/// AllocateRWXMemory - 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.
+///
+void* Memory::AllocateRWX(Memory& M, unsigned NumBytes) {
+  if (NumBytes == 0) return 0;
+
+  static const long pageSize = Process::GetPageSize();
+  unsigned NumPages = (NumBytes+pageSize-1)/pageSize;
+
+  void *pa = mmap(0, pageSize*NumPages, PROT_READ|PROT_WRITE|PROT_EXEC,
+                  MAP_PRIVATE|MAP_ANONYMOUS|MAP_NORESERVE, 0, 0);
+  if (pa == MAP_FAILED) {
+    char msg[MAXPATHLEN];
+    strerror_r(errno, msg, MAXPATHLEN-1);
+    throw std::string("Can't allocate RWX Memory: ") + msg;
+  }
+  M.Address = pa;
+  M.AllocSize = NumPages*pageSize;
+  return pa;
+}
+
+void Memory::ReleaseRWX(Memory& M) {
+  if (M.Address == 0 || M.AllocSize == 0) return;
+  if (0 != munmap(M.Address, M.AllocSize)) {
+    char msg[MAXPATHLEN];
+    strerror_r(errno, msg, MAXPATHLEN-1);
+    throw std::string("Can't release RWX Memory: ") + msg;
+  }
+}
+
+}
+
+// vim: sw=2 smartindent smarttab tw=80 autoindent expandtab