[llvm-commits] CVS: poolalloc/runtime/PoolAllocator/PageManager.cpp PageManager.h

[Chris Lattner]

Changes in directory poolalloc/runtime/PoolAllocator:

PageManager.cpp added (r1.1)
PageManager.h added (r1.1)

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Log message:

Simple implementation of a manager for pages allocated with mmap


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Diffs of the changes:  (+94 -0)

Index: poolalloc/runtime/PoolAllocator/PageManager.cpp
diff -c /dev/null poolalloc/runtime/PoolAllocator/PageManager.cpp:1.1
*** /dev/null	Tue Nov  4 14:26:19 2003
--- poolalloc/runtime/PoolAllocator/PageManager.cpp	Tue Nov  4 14:26:09 2003
***************
*** 0 ****
--- 1,64 ----
+ //===- PageManager.cpp - Implementation of the page allocator -------------===//
+ // 
+ //                       The LLVM Compiler Infrastructure
+ //
+ // This file was developed by the LLVM research group and is distributed under
+ // the University of Illinois Open Source License. See LICENSE.TXT for details.
+ // 
+ //===----------------------------------------------------------------------===//
+ //
+ // This file implements the PageManager.h interface.
+ //
+ //===----------------------------------------------------------------------===//
+ 
+ #include "PageManager.h"
+ #ifndef _POSIX_MAPPED_FILES
+ #define _POSIX_MAPPED_FILES
+ #endif
+ #include "Config/unistd.h"
+ #include "Config/sys/mman.h"
+ #include <cassert>
+ 
+ static unsigned PageSize;
+ 
+ 
+ /// getPageSize - Return the size of the unit of memory allocated by
+ /// AllocatePage.  This is a value that is typically several kilobytes in size.
+ unsigned getPageSize() {
+   if (!PageSize) PageSize = sysconf(_SC_PAGESIZE);
+   return PageSize;
+ }
+ 
+ /// AllocatePage - This function returns a chunk of memory with size and
+ /// alignment specified by getPageSize().
+ void *AllocatePage() {
+ #if defined(i386) || defined(__i386__) || defined(__x86__)
+   /* Linux and *BSD tend to have these flags named differently. */
+ #if defined(MAP_ANON) && !defined(MAP_ANONYMOUS)
+ # define MAP_ANONYMOUS MAP_ANON
+ #endif /* defined(MAP_ANON) && !defined(MAP_ANONYMOUS) */
+ #elif defined(sparc) || defined(__sparc__) || defined(__sparcv9)
+   /* nothing */
+ #else
+   std::cerr << "This architecture is not supported by the pool allocator!\n";
+   abort();
+ #endif
+ 
+ #if defined(__linux__)
+ #define fd 0
+ #else
+ #define fd -1
+ #endif
+ 
+   void *pa = mmap(0, getPageSize(), PROT_READ|PROT_WRITE|PROT_EXEC,
+                   MAP_PRIVATE|MAP_ANONYMOUS, fd, 0);
+   assert(pa != MAP_FAILED && "MMAP FAILED!");
+   return pa;
+ }
+ 
+ 
+ /// FreePage - This function returns the specified page to the pagemanager for
+ /// future allocation.
+ void FreePage(void *Page) {
+   munmap(Page, 1);
+ }


Index: poolalloc/runtime/PoolAllocator/PageManager.h
diff -c /dev/null poolalloc/runtime/PoolAllocator/PageManager.h:1.1
*** /dev/null	Tue Nov  4 14:26:19 2003
--- poolalloc/runtime/PoolAllocator/PageManager.h	Tue Nov  4 14:26:09 2003
***************
*** 0 ****
--- 1,30 ----
+ //===- PageManager.h - Allocates memory on page boundaries ------*- C++ -*-===//
+ // 
+ //                     The LLVM Compiler Infrastructure
+ //
+ // This file was developed by the LLVM research group and is distributed under
+ // the University of Illinois Open Source License. See LICENSE.TXT for details.
+ // 
+ //===----------------------------------------------------------------------===//
+ //
+ // This file defines the interface used by the pool allocator to allocate memory
+ // on large alignment boundaries.
+ //
+ //===----------------------------------------------------------------------===//
+ 
+ #ifndef PAGEMANAGER_H
+ #define PAGEMANAGER_H
+ 
+ /// getPageSize - Return the size of the unit of memory allocated by
+ /// AllocatePage.  This is a value that is typically several kilobytes in size.
+ unsigned getPageSize();
+ 
+ /// AllocatePage - This function returns a chunk of memory with size and
+ /// alignment specified by getPageSize().
+ void *AllocatePage();
+ 
+ /// FreePage - This function returns the specified page to the pagemanager for
+ /// future allocation.
+ void FreePage(void *Page);
+ 
+ #endif