Add support in the LTO library for loading an object from the middle

of an file.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127781 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 32 insertions, 4 deletions

diff --git a/tools/lto/LTOModule.cpp b/tools/lto/LTOModule.cpp
index bdea0c31a6..9de3d5ffce 100644
--- a/tools/lto/LTOModule.cpp
+++ b/tools/lto/LTOModule.cpp
@@ -95,10 +95,19 @@ LTOModule *LTOModule::makeLTOModule(const char *path,
 }
 
 LTOModule *LTOModule::makeLTOModule(int fd, const char *path,
-                                    off_t size,
+                                    size_t size,
+                                    std::string &errMsg) {
+  return makeLTOModule(fd, path, size, 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, size)) {
+  if (error_code ec = MemoryBuffer::getOpenFile(fd, path, buffer, file_size,
+                                                map_size, offset, false)) {
     errMsg = ec.message();
     return NULL;
   }
diff --git a/tools/lto/LTOModule.h b/tools/lto/LTOModule.h
index 21e8475177..303151293b 100644
--- a/tools/lto/LTOModule.h
+++ b/tools/lto/LTOModule.h
@@ -52,7 +52,12 @@ struct LTOModule {
     static LTOModule*        makeLTOModule(const char* path,
                                           std::string& errMsg);
     static LTOModule*        makeLTOModule(int fd, const char *path,
-                                           off_t size,
+                                           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);
     static LTOModule*        makeLTOModule(const void* mem, size_t length,
                                            std::string& errMsg);
diff --git a/tools/lto/lto.cpp b/tools/lto/lto.cpp
index f48570c149..cbac047c75 100644
--- a/tools/lto/lto.cpp
+++ b/tools/lto/lto.cpp
@@ -95,12 +95,25 @@ lto_module_t lto_module_create(const char* path)
 // loads an object file from disk
 // returns NULL on error (check lto_get_error_message() for details)
 //
-lto_module_t lto_module_create_from_fd(int fd, const char *path, off_t size)
+lto_module_t lto_module_create_from_fd(int fd, const char *path, size_t size)
 {
      return LTOModule::makeLTOModule(fd, path, size, sLastErrorString);
 }
 
 //
+// loads an object file from disk
+// returns NULL on error (check lto_get_error_message() for details)
+//
+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);
+}
+
+//
 // loads an object file from memory 
 // returns NULL on error (check lto_get_error_message() for details)
 //
diff --git a/tools/lto/lto.exports b/tools/lto/lto.exports
index a3740911ed..04b37e1f45 100644
--- a/tools/lto/lto.exports
+++ b/tools/lto/lto.exports
@@ -2,6 +2,7 @@ lto_get_error_message
 lto_get_version
 lto_module_create
 lto_module_create_from_fd
+lto_module_create_from_fd_at_offset
 lto_module_create_from_memory
 lto_module_get_num_symbols
 lto_module_get_symbol_attribute