Split getOpenFile into getOpenFile and getOpenFileSlice.

The main observation is that we never need both the filesize and the map size.
When mapping a slice of a file, it doesn't make sense to request a null
terminator and that would be the only case where the filesize would be used.

There are other cleanups that should be done in this area:

* A client should not have to pass the size (even an explicit -1) to say if
  it wants a null terminator or not, so we should probably swap the argument
  order.
* The default should be to not require a null terminator. Very few clients
  require this, but many end up asking for it just because it is the default.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186984 91177308-0d34-0410-b5e6-96231b3b80d8

5 files changed, 9 insertions, 13 deletions

diff --git a/tools/gold/gold-plugin.cpp b/tools/gold/gold-plugin.cpp
index 133eca4..7771709 100644
--- a/tools/gold/gold-plugin.cpp
+++ b/tools/gold/gold-plugin.cpp
@@ -252,9 +252,8 @@ static ld_plugin_status claim_file_hook(const ld_plugin_input_file *file,
     if (file->offset) {
       offset = file->offset;
     }
-    if (error_code ec =
-        MemoryBuffer::getOpenFile(file->fd, file->name, buffer, -1,
-                                  file->filesize, offset, false)) {
+    if (error_code ec = MemoryBuffer::getOpenFileSlice(
+            file->fd, file->name, buffer, file->filesize, offset)) {
       (*message)(LDPL_ERROR, ec.message().c_str());
       return LDPS_ERR;
     }
diff --git a/tools/llvm-ar/llvm-ar.cpp b/tools/llvm-ar/llvm-ar.cpp
index 116143e..261446c 100644
--- a/tools/llvm-ar/llvm-ar.cpp
+++ b/tools/llvm-ar/llvm-ar.cpp
@@ -770,9 +770,9 @@ static void performWriteOperation(ArchiveOperation Operation,
       failIfError(sys::fs::status(FD, Status), FileName);
 
       OwningPtr<MemoryBuffer> File;
-      failIfError(
-          MemoryBuffer::getOpenFile(FD, FileName, File, Status.getSize()),
-          FileName);
+      failIfError(MemoryBuffer::getOpenFile(FD, FileName, File,
+                                            Status.getSize(), false),
+                  FileName);
 
       StringRef Name = sys::path::filename(FileName);
       if (Name.size() < 16)
diff --git a/tools/lto/LTOModule.cpp b/tools/lto/LTOModule.cpp
index 5ee43ba..6626eaa 100644
--- a/tools/lto/LTOModule.cpp
+++ b/tools/lto/LTOModule.cpp
@@ -209,17 +209,16 @@ LTOModule *LTOModule::makeLTOModule(const char *path, std::string &errMsg) {
 
 LTOModule *LTOModule::makeLTOModule(int fd, const char *path,
                                     size_t size, std::string &errMsg) {
-  return makeLTOModule(fd, path, size, size, 0, errMsg);
+  return makeLTOModule(fd, path, size, 0, errMsg);
 }
 
 LTOModule *LTOModule::makeLTOModule(int fd, const char *path,
-                                    size_t file_size,
                                     size_t map_size,
                                     off_t offset,
                                     std::string &errMsg) {
   OwningPtr<MemoryBuffer> buffer;
-  if (error_code ec = MemoryBuffer::getOpenFile(fd, path, buffer, file_size,
-                                                map_size, offset, false)) {
+  if (error_code ec =
+          MemoryBuffer::getOpenFileSlice(fd, path, buffer, map_size, offset)) {
     errMsg = ec.message();
     return NULL;
   }
diff --git a/tools/lto/LTOModule.h b/tools/lto/LTOModule.h
index 83f3a7d..902e9c5 100644
--- a/tools/lto/LTOModule.h
+++ b/tools/lto/LTOModule.h
@@ -82,7 +82,6 @@ public:
   static LTOModule *makeLTOModule(int fd, const char *path,
                                   size_t size, std::string &errMsg);
   static LTOModule *makeLTOModule(int fd, const char *path,
-                                  size_t file_size,
                                   size_t map_size,
                                   off_t offset,
                                   std::string& errMsg);
diff --git a/tools/lto/lto.cpp b/tools/lto/lto.cpp
index 11ad532..e0df81a 100644
--- a/tools/lto/lto.cpp
+++ b/tools/lto/lto.cpp
@@ -78,8 +78,7 @@ lto_module_t lto_module_create_from_fd_at_offset(int fd, const char *path,
                                                  size_t file_size,
                                                  size_t map_size,
                                                  off_t offset) {
-  return LTOModule::makeLTOModule(fd, path, file_size, map_size,
-                                  offset, sLastErrorString);
+  return LTOModule::makeLTOModule(fd, path, map_size, offset, sLastErrorString);
 }
 
 /// lto_module_create_from_memory - Loads an object file from memory. Returns