[ThinLTO] Support for specifying function index from pass manager

[oota-llvm.git] / lib / Transforms / IPO / PassManagerBuilder.cpp

diff --git a/lib/Transforms/IPO/PassManagerBuilder.cpp b/lib/Transforms/IPO/PassManagerBuilder.cpp
index 6b113ff9b7f3a4c0319a0abbc16cbaea0297641a..b8d1b7e78e354949fb09c5028d40ed4a90f4270b 100644 (file)
--- a/lib/Transforms/IPO/PassManagerBuilder.cpp
+++ b/lib/Transforms/IPO/PassManagerBuilder.cpp
@@ -18,6 +18,7 @@
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/Analysis/Passes.h"
 #include "llvm/IR/DataLayout.h"
+#include "llvm/IR/FunctionInfo.h"
 #include "llvm/IR/Verifier.h"
 #include "llvm/IR/LegacyPassManager.h"
 #include "llvm/Support/CommandLine.h"
@@ -99,11 +100,16 @@ static cl::opt<bool> EnableNonLTOGlobalsModRef(
     cl::desc(
         "Enable the GlobalsModRef AliasAnalysis outside of the LTO pipeline."));
 
+static cl::opt<bool> EnableLoopLoadElim(
+    "enable-loop-load-elim", cl::init(false), cl::Hidden,
+    cl::desc("Enable the new, experimental LoopLoadElimination Pass"));
+
 PassManagerBuilder::PassManagerBuilder() {
     OptLevel = 2;
     SizeLevel = 0;
     LibraryInfo = nullptr;
     Inliner = nullptr;
+    FunctionIndex = nullptr;
     DisableUnitAtATime = false;
     DisableUnrollLoops = false;
     BBVectorize = RunBBVectorization;
@@ -260,6 +266,7 @@ void PassManagerBuilder::populateModulePassManager(
   MPM.add(createLoopRotatePass(SizeLevel == 2 ? 0 : -1));
   MPM.add(createLICMPass());                  // Hoist loop invariants
   MPM.add(createLoopUnswitchPass(SizeLevel || OptLevel < 3));
+  MPM.add(createCFGSimplificationPass());
   MPM.add(createInstructionCombiningPass());
   MPM.add(createIndVarSimplifyPass());        // Canonicalize indvars
   MPM.add(createLoopIdiomPass());             // Recognize idioms like memset.
@@ -377,6 +384,12 @@ void PassManagerBuilder::populateModulePassManager(
     MPM.add(createLoopDistributePass());
 
   MPM.add(createLoopVectorizePass(DisableUnrollLoops, LoopVectorize));
+
+  // Eliminate loads by forwarding stores from the previous iteration to loads
+  // of the current iteration.
+  if (EnableLoopLoadElim)
+    MPM.add(createLoopLoadEliminationPass());
+
   // FIXME: Because of #pragma vectorize enable, the passes below are always
   // inserted in the pipeline, even when the vectorizer doesn't run (ex. when
   // on -O1 and no #pragma is found). Would be good to have these two passes
@@ -465,12 +478,16 @@ void PassManagerBuilder::addLTOOptimizationPasses(legacy::PassManagerBase &PM) {
   // Provide AliasAnalysis services for optimizations.
   addInitialAliasAnalysisPasses(PM);
 
+  if (FunctionIndex)
+    PM.add(createFunctionImportPass(FunctionIndex));
+
   // Propagate constants at call sites into the functions they call.  This
   // opens opportunities for globalopt (and inlining) by substituting function
   // pointers passed as arguments to direct uses of functions.
   PM.add(createIPSCCPPass());
 
   // Now that we internalized some globals, see if we can hack on them!
+  PM.add(createFunctionAttrsPass()); // Add norecurse if possible.
   PM.add(createGlobalOptimizerPass());
 
   // Linking modules together can lead to duplicated global constants, only