vendor/llvm/llvm-trunk-r304149

1 files changed, 19 insertions, 6 deletions

diff --git a/lib/Passes/PassBuilder.cpp b/lib/Passes/PassBuilder.cpp
index 6ece7965ce646..abc53e97aa728 100644
--- a/lib/Passes/PassBuilder.cpp
+++ b/lib/Passes/PassBuilder.cpp
@@ -155,6 +155,11 @@ static cl::opt<bool>
                        cl::Hidden, cl::ZeroOrMore,
                        cl::desc("Run Partial inlinining pass"));
 
+static cl::opt<bool>
+    RunNewGVN("enable-npm-newgvn", cl::init(false),
+              cl::Hidden, cl::ZeroOrMore,
+              cl::desc("Run NewGVN instead of GVN"));
+
 static cl::opt<bool> EnableGVNHoist(
     "enable-npm-gvn-hoist", cl::init(false), cl::Hidden,
     cl::desc("Enable the GVN hoisting pass for the new PM (default = off)"));
@@ -336,10 +341,7 @@ PassBuilder::buildFunctionSimplificationPipeline(OptimizationLevel Level,
   // Rotate Loop - disable header duplication at -Oz
   LPM1.addPass(LoopRotatePass(Level != Oz));
   LPM1.addPass(LICMPass());
-#if 0
-  // The LoopUnswitch pass isn't yet ported to the new pass manager.
-  LPM1.addPass(LoopUnswitchPass(/* OptimizeForSize */ Level != O3));
-#endif
+  LPM1.addPass(SimpleLoopUnswitchPass());
   LPM2.addPass(IndVarSimplifyPass());
   LPM2.addPass(LoopIdiomRecognizePass());
   LPM2.addPass(LoopDeletionPass());
@@ -357,7 +359,10 @@ PassBuilder::buildFunctionSimplificationPipeline(OptimizationLevel Level,
   if (Level != O1) {
     // These passes add substantial compile time so skip them at O1.
     FPM.addPass(MergedLoadStoreMotionPass());
-    FPM.addPass(GVN());
+    if (RunNewGVN)
+      FPM.addPass(NewGVNPass());
+    else
+      FPM.addPass(GVN());
   }
 
   // Specially optimize memory movement as it doesn't look like dataflow in SSA.
@@ -429,6 +434,11 @@ static void addPGOInstrPasses(ModulePassManager &MPM, bool DebugLogging,
     MPM.addPass(createModuleToPostOrderCGSCCPassAdaptor(std::move(CGPipeline)));
   }
 
+  // Delete anything that is now dead to make sure that we don't instrument
+  // dead code. Instrumentation can end up keeping dead code around and
+  // dramatically increase code size.
+  MPM.addPass(GlobalDCEPass());
+
   if (RunProfileGen) {
     MPM.addPass(PGOInstrumentationGen());
 
@@ -774,7 +784,10 @@ ModulePassManager PassBuilder::buildLTODefaultPipeline(OptimizationLevel Level,
   // FIXME: once we fix LoopPass Manager, add LICM here.
   // FIXME: once we provide support for enabling MLSM, add it here.
   // FIXME: once we provide support for enabling NewGVN, add it here.
-  MainFPM.addPass(GVN());
+  if (RunNewGVN)
+    MainFPM.addPass(NewGVNPass());
+  else
+    MainFPM.addPass(GVN());
 
   // Remove dead memcpy()'s.
   MainFPM.addPass(MemCpyOptPass());