It's not necessary to do rounding for alloca operations when the requested
alignment is equal to the stack alignment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40004 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/System/Unix/MappedFile.inc b/lib/System/Unix/MappedFile.inc
new file mode 100644
index 0000000..91b92ec
--- /dev/null
+++ b/lib/System/Unix/MappedFile.inc
@@ -0,0 +1,154 @@
+//===- Unix/MappedFile.cpp - Unix MappedFile 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 generic Unix implementation of the MappedFile concept.
+//
+//===----------------------------------------------------------------------===//
+
+//===----------------------------------------------------------------------===//
+//=== WARNING: Implementation here must contain only generic UNIX code that
+//=== is guaranteed to work on *all* UNIX variants.
+//===----------------------------------------------------------------------===//
+
+#include "Unix.h"
+#include "llvm/System/Process.h"
+
+#ifdef HAVE_FCNTL_H
+#include <fcntl.h>
+#endif
+
+#ifdef HAVE_SYS_MMAN_H
+#include <sys/mman.h>
+#endif
+
+#ifdef HAVE_SYS_STAT_H
+#include <sys/stat.h>
+#endif
+
+namespace llvm {
+using namespace sys;
+
+struct sys::MappedFileInfo {
+ int FD;
+ off_t Size;
+};
+
+bool MappedFile::initialize(std::string* ErrMsg) {
+ int mode = 0;
+ if (options_ & READ_ACCESS)
+ if (options_ & WRITE_ACCESS)
+ mode = O_RDWR;
+ else
+ mode = O_RDONLY;
+ else if (options_ & WRITE_ACCESS)
+ mode = O_WRONLY;
+
+ int FD = ::open(path_.c_str(), mode);
+ if (FD < 0) {
+ MakeErrMsg(ErrMsg, "can't open file '" + path_.toString() + "'");
+ return true;
+ }
+ const FileStatus *Status = path_.getFileStatus(false, ErrMsg);
+ if (!Status) {
+ ::close(FD);
+ return true;
+ }
+ info_ = new MappedFileInfo;
+ info_->FD = FD;
+ info_->Size = Status->getSize();
+ return false;
+}
+
+void MappedFile::terminate() {
+ assert(info_ && "MappedFile not initialized");
+ ::close(info_->FD);
+ delete info_;
+ info_ = 0;
+}
+
+void MappedFile::unmap() {
+ assert(info_ && "MappedFile not initialized");
+ if (isMapped()) {
+ if (options_ & WRITE_ACCESS)
+ ::msync(base_, info_->Size, MS_SYNC);
+ ::munmap(base_, info_->Size);
+ base_ = 0; // Mark this as non-mapped.
+ }
+}
+
+void* MappedFile::map(std::string* ErrMsg) {
+ assert(info_ && "MappedFile not initialized");
+ if (!isMapped()) {
+ int prot = PROT_NONE;
+ int flags = 0;
+#ifdef MAP_FILE
+ flags |= MAP_FILE;
+#endif
+ if (options_ == 0) {
+ prot = PROT_READ;
+ flags = MAP_PRIVATE;
+ } else {
+ if (options_ & READ_ACCESS)
+ prot |= PROT_READ;
+ if (options_ & WRITE_ACCESS)
+ prot |= PROT_WRITE;
+ if (options_ & EXEC_ACCESS)
+ prot |= PROT_EXEC;
+ if (options_ & SHARED_MAPPING)
+ flags |= MAP_SHARED;
+ else
+ flags |= MAP_PRIVATE;
+ }
+ size_t map_size = ((info_->Size / Process::GetPageSize())+1) *
+ Process::GetPageSize();
+
+ base_ = ::mmap(0, map_size, prot, flags, info_->FD, 0);
+ if (base_ == MAP_FAILED) {
+ MakeErrMsg(ErrMsg, "Can't map file:" + path_.toString());
+ return 0;
+ }
+ }
+ return base_;
+}
+
+size_t MappedFile::size() const {
+ assert(info_ && "MappedFile not initialized");
+ return info_->Size;
+}
+
+bool MappedFile::size(size_t new_size, std::string* ErrMsg) {
+ assert(info_ && "MappedFile not initialized");
+
+ // Take the mapping out of memory
+ this->unmap();
+
+ // Adjust the current size to a page boundary
+ size_t cur_size = ((info_->Size / Process::GetPageSize())+1) *
+ Process::GetPageSize();
+
+ // Adjust the new_size to a page boundary
+ new_size = ((new_size / Process::GetPageSize())+1) *
+ Process::GetPageSize();
+
+ // If the file needs to be extended
+ if (new_size > cur_size) {
+ // Ensure we can allocate at least the idodes necessary to handle the
+ // file size requested.
+ if ((off_t)-1 == ::lseek(info_->FD, new_size, SEEK_SET))
+ return MakeErrMsg(ErrMsg, "Can't lseek: ");
+ if (-1 == ::write(info_->FD, "\0", 1))
+ return MakeErrMsg(ErrMsg, "Can't write: ");
+ }
+
+ // Put the mapping back into memory.
+ return this->map(ErrMsg);
+}
+
+}
+