[LTO] Call llvm_shutdown on exit

[davide]

Summary

On a non-lto build is a nop. On a LTO build, we deallocate/destroy managed static and this allows us to get the output of, e.g., -time-passes without performing a full shutdown

ELF/Error.cpp

 //===- Error.cpp ----------------------------------------------------------===//
 //
 //                             The LLVM Linker
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 
 #include "Error.h"
 #include "Config.h"
 
 #include "llvm/ADT/Twine.h"
 #include "llvm/Support/Error.h"
+#include "llvm/Support/ManagedStatic.h"
 #include "llvm/Support/raw_ostream.h"
 
 #if !defined(_MSC_VER) && !defined(__MINGW32__)
 #include <unistd.h>
 #endif
 
 using namespace llvm;
 

 
 void elf::error(std::error_code EC, const Twine &Prefix) {
   error(Prefix + ": " + EC.message());
 }
 
 void elf::exitLld(int Val) {
   outs().flush();
   errs().flush();
+
+  // Dealloc/destroy ManagedStatic variables before calling
+  // _exit(). In a non-LTO build, this is a nop. In an LTO
+  // build allows us to get the output of -time-passes.
+  llvm_shutdown();
+
   _exit(Val);
 }
 
 void elf::fatal(const Twine &Msg) {
   *ErrorOS << Argv0 << ": error: " << Msg << "\n";
   exitLld(1);
 }
 
 void elf::fatal(std::error_code EC, const Twine &Prefix) {
   fatal(Prefix + ": " + EC.message());
 }
 
 } // namespace lld

test/ELF/lto/timepasses.ll

+; REQUIRES: x86
+; RUN: llvm-as %s -o %t.o
+; RUN: ld.lld -m elf_x86_64 %t.o -o %t.so -shared -mllvm -time-passes 2>&1 | FileCheck %s
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+define void @patatino() {
+  ret void
+}
+
+; We should get the output of -time-passes even when --full-shutdown is not specified.
+; CHECK: Total Execution Time