Move createReversePostOrderFunctionAttrsPass right after the inliner is done

This is where it was originally, until LoopVersioningLICM was
inserted before in r259986, I don't believe it was on purpose.

Differential Revision: http://reviews.llvm.org/D19809

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 268252

2 files changed, 11 insertions, 8 deletions

diff --git a/llvm/lib/Transforms/IPO/PassManagerBuilder.cpp b/llvm/lib/Transforms/IPO/PassManagerBuilder.cpp
index b4af849baf3..71ec8aeafa2 100644
--- a/llvm/lib/Transforms/IPO/PassManagerBuilder.cpp
+++ b/llvm/lib/Transforms/IPO/PassManagerBuilder.cpp
@@ -399,6 +399,14 @@ void PassManagerBuilder::populateModulePassManager(
 
   addFunctionSimplificationPasses(MPM);
 
+  // FIXME: This is a HACK! The inliner pass above implicitly creates a CGSCC
+  // pass manager that we are specifically trying to avoid. To prevent this
+  // we must insert a no-op module pass to reset the pass manager.
+  MPM.add(createBarrierNoopPass());
+
+  if (!DisableUnitAtATime)
+    MPM.add(createReversePostOrderFunctionAttrsPass());
+
   // If we are planning to perform ThinLTO later, let's not bloat the code with
   // unrolling/vectorization/... now. We'll first run the inliner + CGSCC passes
   // during ThinLTO and perform the rest of the optimizations afterward.
@@ -410,11 +418,6 @@ void PassManagerBuilder::populateModulePassManager(
     return;
   }
 
-  // FIXME: This is a HACK! The inliner pass above implicitly creates a CGSCC
-  // pass manager that we are specifically trying to avoid. To prevent this
-  // we must insert a no-op module pass to reset the pass manager.
-  MPM.add(createBarrierNoopPass());
-
   // Scheduling LoopVersioningLICM when inlining is over, because after that
   // we may see more accurate aliasing. Reason to run this late is that too
   // early versioning may prevent further inlining due to increase of code
@@ -425,9 +428,6 @@ void PassManagerBuilder::populateModulePassManager(
     MPM.add(createLICMPass());                  // Hoist loop invariants
   }
 
-  if (!DisableUnitAtATime)
-    MPM.add(createReversePostOrderFunctionAttrsPass());
-
   if (!DisableUnitAtATime && OptLevel > 1 && !PrepareForLTO)
     // Remove avail extern fns and globals definitions if we aren't
     // compiling an object file for later LTO. For LTO we want to preserve
diff --git a/llvm/test/Other/pass-pipelines.ll b/llvm/test/Other/pass-pipelines.ll
index 778376a7d39..5e3e38ef1d9 100644
--- a/llvm/test/Other/pass-pipelines.ll
+++ b/llvm/test/Other/pass-pipelines.ll
@@ -55,6 +55,9 @@
 ; Next we break out of the main Function passes inside the CGSCC pipeline with
 ; a barrier pass.
 ; CHECK-O2: A No-Op Barrier Pass
+; Inferring function attribute should be immediately after the CGSCC pipeline.
+; CHECK-O2-NEXT: CallGraph
+; CHECK-O2-NEXT: Deduce function attributes in RPO
 ; CHECK-O2-NOT: Manager
 ; Next is the late function pass pipeline.
 ; CHECK-O2: FunctionPass Manager