Gold-plugin: Broaden scope of get/release_input_file to scope of Module.

Summary:
Move calls to get_input_file and release_input_file out of
getModuleForFile(). Otherwise release_input_file may end up
unmapping a view of the file while the view is still being
used by the Module (on 32-bit hosts).

Fix for PR22482.

Test Plan: Add test using --no-map-whole-files.

Reviewers: rafael, nlewycky

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D7539

llvm-svn: 228842

1 files changed, 10 insertions, 9 deletions

diff --git a/llvm/tools/gold/gold-plugin.cpp b/llvm/tools/gold/gold-plugin.cpp
index 5d5db5a33a2..dd6d47f5d70 100644
--- a/llvm/tools/gold/gold-plugin.cpp
+++ b/llvm/tools/gold/gold-plugin.cpp
@@ -560,11 +560,9 @@ static void freeSymName(ld_plugin_symbol &Sym) {
 }
 
 static std::unique_ptr<Module>
-getModuleForFile(LLVMContext &Context, claimed_file &F, raw_fd_ostream *ApiFile,
+getModuleForFile(LLVMContext &Context, claimed_file &F,
+                 off_t Filesize, raw_fd_ostream *ApiFile,
                  StringSet<> &Internalize, StringSet<> &Maybe) {
-  ld_plugin_input_file File;
-  if (get_input_file(F.handle, &File) != LDPS_OK)
-    message(LDPL_FATAL, "Failed to get file information");
 
   if (get_symbols(F.handle, F.syms.size(), &F.syms[0]) != LDPS_OK)
     message(LDPL_FATAL, "Failed to get symbol information");
@@ -573,7 +571,7 @@ getModuleForFile(LLVMContext &Context, claimed_file &F, raw_fd_ostream *ApiFile,
   if (get_view(F.handle, &View) != LDPS_OK)
     message(LDPL_FATAL, "Failed to get a view of file");
 
-  MemoryBufferRef BufferRef(StringRef((const char *)View, File.filesize), "");
+  MemoryBufferRef BufferRef(StringRef((const char *)View, Filesize), "");
   ErrorOr<std::unique_ptr<object::IRObjectFile>> ObjOrErr =
       object::IRObjectFile::create(BufferRef, Context);
 
@@ -581,9 +579,6 @@ getModuleForFile(LLVMContext &Context, claimed_file &F, raw_fd_ostream *ApiFile,
     message(LDPL_FATAL, "Could not read bitcode from file : %s",
             EC.message().c_str());
 
-  if (release_input_file(F.handle) != LDPS_OK)
-    message(LDPL_FATAL, "Failed to release file information");
-
   object::IRObjectFile &Obj = **ObjOrErr;
 
   Module &M = Obj.getModule();
@@ -802,8 +797,12 @@ static ld_plugin_status allSymbolsReadHook(raw_fd_ostream *ApiFile) {
   StringSet<> Internalize;
   StringSet<> Maybe;
   for (claimed_file &F : Modules) {
+    ld_plugin_input_file File;
+    if (get_input_file(F.handle, &File) != LDPS_OK)
+      message(LDPL_FATAL, "Failed to get file information");
     std::unique_ptr<Module> M =
-        getModuleForFile(Context, F, ApiFile, Internalize, Maybe);
+        getModuleForFile(Context, F, File.filesize, ApiFile,
+                         Internalize, Maybe);
     if (!options::triple.empty())
       M->setTargetTriple(options::triple.c_str());
     else if (M->getTargetTriple().empty()) {
@@ -812,6 +811,8 @@ static ld_plugin_status allSymbolsReadHook(raw_fd_ostream *ApiFile) {
 
     if (L.linkInModule(M.get()))
       message(LDPL_FATAL, "Failed to link module");
+    if (release_input_file(F.handle) != LDPS_OK)
+      message(LDPL_FATAL, "Failed to release file information");
   }
 
   for (const auto &Name : Internalize) {