[CodeGen] Insert TargetLibraryInfoWrapperPass before anything else.

Currently, TargetLibraryInfoWrapperPass is inserted by PMBuilder.
However, some passes are inserted manually before the PMBuilder
ones - if any of them happens to use TargetLibraryInfoWrapperPass,
it'll get a default-constructed one, with an unknown target triple.
This happens to InstrProfiling in D21736, breaking it.

Differential Revision: http://reviews.llvm.org/D21737

llvm-svn: 287688

1 files changed, 9 insertions, 2 deletions

diff --git a/clang/lib/CodeGen/BackendUtil.cpp b/clang/lib/CodeGen/BackendUtil.cpp
index ec790e411e0..87937c057be 100644
--- a/clang/lib/CodeGen/BackendUtil.cpp
+++ b/clang/lib/CodeGen/BackendUtil.cpp
@@ -298,9 +298,13 @@ void EmitAssemblyHelper::CreatePasses(legacy::PassManager &MPM,
 
   PassManagerBuilderWrapper PMBuilder(CodeGenOpts, LangOpts);
 
-  // Figure out TargetLibraryInfo.
+  // Figure out TargetLibraryInfo.  This needs to be added to MPM and FPM
+  // manually (and not via PMBuilder), since some passes (eg. InstrProfiling)
+  // are inserted before PMBuilder ones - they'd get the default-constructed
+  // TLI with an unknown target otherwise.
   Triple TargetTriple(TheModule->getTargetTriple());
-  PMBuilder.LibraryInfo = createTLII(TargetTriple, CodeGenOpts);
+  std::unique_ptr<TargetLibraryInfoImpl> TLII(
+      createTLII(TargetTriple, CodeGenOpts));
 
   switch (Inlining) {
   case CodeGenOptions::NoInlining:
@@ -333,6 +337,8 @@ void EmitAssemblyHelper::CreatePasses(legacy::PassManager &MPM,
   PMBuilder.PrepareForLTO = CodeGenOpts.PrepareForLTO;
   PMBuilder.RerollLoops = CodeGenOpts.RerollLoops;
 
+  MPM.add(new TargetLibraryInfoWrapperPass(*TLII));
+
   // Add target-specific passes that need to run as early as possible.
   if (TM)
     PMBuilder.addExtension(
@@ -416,6 +422,7 @@ void EmitAssemblyHelper::CreatePasses(legacy::PassManager &MPM,
   }
 
   // Set up the per-function pass manager.
+  FPM.add(new TargetLibraryInfoWrapperPass(*TLII));
   if (CodeGenOpts.VerifyModule)
     FPM.add(createVerifierPass());