MergedLoadStoreMotion pass
[oota-llvm.git] / lib / Transforms / IPO / PassManagerBuilder.cpp
index 9e328b9ac9769bea486f2bb6f6d5474774d3a64f..701fb462b4fdad1e6b50bf1bcdee2f8fab2d4d0e 100644 (file)
 
 
 #include "llvm/Transforms/IPO/PassManagerBuilder.h"
-
 #include "llvm-c/Transforms/PassManagerBuilder.h"
-
-#include "llvm/PassManager.h"
-#include "llvm/DefaultPasses.h"
-#include "llvm/PassManager.h"
+#include "llvm/ADT/SmallVector.h"
 #include "llvm/Analysis/Passes.h"
-#include "llvm/Analysis/Verifier.h"
+#include "llvm/IR/Verifier.h"
+#include "llvm/PassManager.h"
 #include "llvm/Support/CommandLine.h"
+#include "llvm/Support/ManagedStatic.h"
 #include "llvm/Target/TargetLibraryInfo.h"
+#include "llvm/Transforms/IPO.h"
 #include "llvm/Transforms/Scalar.h"
 #include "llvm/Transforms/Vectorize.h"
-#include "llvm/Transforms/IPO.h"
-#include "llvm/ADT/SmallVector.h"
-#include "llvm/Support/ManagedStatic.h"
 
 using namespace llvm;
 
 static cl::opt<bool>
-RunVectorization("vectorize", cl::desc("Run vectorization passes"));
+RunLoopVectorization("vectorize-loops", cl::Hidden,
+                     cl::desc("Run the Loop vectorization passes"));
+
+static cl::opt<bool>
+RunSLPVectorization("vectorize-slp", cl::Hidden,
+                    cl::desc("Run the SLP vectorization passes"));
+
+static cl::opt<bool>
+RunBBVectorization("vectorize-slp-aggressive", cl::Hidden,
+                    cl::desc("Run the BB vectorization passes"));
 
 static cl::opt<bool>
 UseGVNAfterVectorization("use-gvn-after-vectorization",
@@ -41,18 +46,30 @@ UseGVNAfterVectorization("use-gvn-after-vectorization",
   cl::desc("Run GVN instead of Early CSE after vectorization passes"));
 
 static cl::opt<bool> UseNewSROA("use-new-sroa",
-  cl::init(false), cl::Hidden,
+  cl::init(true), cl::Hidden,
   cl::desc("Enable the new, experimental SROA pass"));
 
+static cl::opt<bool>
+RunLoopRerolling("reroll-loops", cl::Hidden,
+                 cl::desc("Run the loop rerolling pass"));
+
+static cl::opt<bool> RunLoadCombine("combine-loads", cl::init(false),
+                                    cl::Hidden,
+                                    cl::desc("Run the load combining pass"));
+
 PassManagerBuilder::PassManagerBuilder() {
     OptLevel = 2;
     SizeLevel = 0;
-    LibraryInfo = 0;
-    Inliner = 0;
-    DisableSimplifyLibCalls = false;
+    LibraryInfo = nullptr;
+    Inliner = nullptr;
+    DisableTailCalls = false;
     DisableUnitAtATime = false;
     DisableUnrollLoops = false;
-    Vectorize = RunVectorization;
+    BBVectorize = RunBBVectorization;
+    SLPVectorize = RunSLPVectorization;
+    LoopVectorize = RunLoopVectorization;
+    RerollLoops = RunLoopRerolling;
+    LoadCombine = RunLoadCombine;
 }
 
 PassManagerBuilder::~PassManagerBuilder() {
@@ -117,8 +134,16 @@ void PassManagerBuilder::populateModulePassManager(PassManagerBase &MPM) {
   if (OptLevel == 0) {
     if (Inliner) {
       MPM.add(Inliner);
-      Inliner = 0;
+      Inliner = nullptr;
     }
+
+    // FIXME: This is a HACK! The inliner pass above implicitly creates a CGSCC
+    // pass manager, but we don't want to add extensions into that pass manager.
+    // To prevent this we must insert a no-op module pass to reset the pass
+    // manager to get the same behavior as EP_OptimizerLast in non-O0 builds.
+    if (!GlobalExtensions->empty() || !Extensions.empty())
+      MPM.add(createBarrierNoopPass());
+
     addExtensionsToPM(EP_EnabledOnOptLevel0, MPM);
     return;
   }
@@ -131,12 +156,13 @@ void PassManagerBuilder::populateModulePassManager(PassManagerBase &MPM) {
   if (!DisableUnitAtATime) {
     addExtensionsToPM(EP_ModuleOptimizerEarly, MPM);
 
+    MPM.add(createIPSCCPPass());              // IP SCCP
     MPM.add(createGlobalOptimizerPass());     // Optimize out global vars
 
-    MPM.add(createIPSCCPPass());              // IP SCCP
     MPM.add(createDeadArgEliminationPass());  // Dead argument elimination
 
     MPM.add(createInstructionCombiningPass());// Clean up after IPCP & DAE
+    addExtensionsToPM(EP_Peephole, MPM);
     MPM.add(createCFGSimplificationPass());   // Clean up after IPCP & DAE
   }
 
@@ -145,7 +171,7 @@ void PassManagerBuilder::populateModulePassManager(PassManagerBase &MPM) {
     MPM.add(createPruneEHPass());             // Remove dead EH info
   if (Inliner) {
     MPM.add(Inliner);
-    Inliner = 0;
+    Inliner = nullptr;
   }
   if (!DisableUnitAtATime)
     MPM.add(createFunctionAttrsPass());       // Set readonly/readnone attrs
@@ -159,14 +185,14 @@ void PassManagerBuilder::populateModulePassManager(PassManagerBase &MPM) {
   else
     MPM.add(createScalarReplAggregatesPass(-1, false));
   MPM.add(createEarlyCSEPass());              // Catch trivial redundancies
-  if (!DisableSimplifyLibCalls)
-    MPM.add(createSimplifyLibCallsPass());    // Library Call Optimizations
   MPM.add(createJumpThreadingPass());         // Thread jumps.
   MPM.add(createCorrelatedValuePropagationPass()); // Propagate conditionals
   MPM.add(createCFGSimplificationPass());     // Merge & remove BBs
   MPM.add(createInstructionCombiningPass());  // Combine silly seq's
+  addExtensionsToPM(EP_Peephole, MPM);
 
-  MPM.add(createTailCallEliminationPass());   // Eliminate tail calls
+  if (!DisableTailCalls)
+    MPM.add(createTailCallEliminationPass()); // Eliminate tail calls
   MPM.add(createCFGSimplificationPass());     // Merge & remove BBs
   MPM.add(createReassociatePass());           // Reassociate expressions
   MPM.add(createLoopRotatePass());            // Rotate Loop
@@ -176,36 +202,71 @@ void PassManagerBuilder::populateModulePassManager(PassManagerBase &MPM) {
   MPM.add(createIndVarSimplifyPass());        // Canonicalize indvars
   MPM.add(createLoopIdiomPass());             // Recognize idioms like memset.
   MPM.add(createLoopDeletionPass());          // Delete dead loops
+
   if (!DisableUnrollLoops)
-    MPM.add(createLoopUnrollPass());          // Unroll small loops
+    MPM.add(createSimpleLoopUnrollPass());    // Unroll small loops
   addExtensionsToPM(EP_LoopOptimizerEnd, MPM);
 
-  if (OptLevel > 1)
+  if (OptLevel > 1) {
+    MPM.add(createMergedLoadStoreMotionPass()); // Merge load/stores in diamond
     MPM.add(createGVNPass());                 // Remove redundancies
+  }
   MPM.add(createMemCpyOptPass());             // Remove memcpy / form memset
   MPM.add(createSCCPPass());                  // Constant prop with SCCP
 
   // Run instcombine after redundancy elimination to exploit opportunities
   // opened up by them.
   MPM.add(createInstructionCombiningPass());
+  addExtensionsToPM(EP_Peephole, MPM);
   MPM.add(createJumpThreadingPass());         // Thread jumps
   MPM.add(createCorrelatedValuePropagationPass());
   MPM.add(createDeadStoreEliminationPass());  // Delete dead stores
 
   addExtensionsToPM(EP_ScalarOptimizerLate, MPM);
 
-  if (Vectorize) {
+  if (RerollLoops)
+    MPM.add(createLoopRerollPass());
+  if (SLPVectorize)
+    MPM.add(createSLPVectorizerPass());   // Vectorize parallel scalar chains.
+
+  if (BBVectorize) {
     MPM.add(createBBVectorizePass());
     MPM.add(createInstructionCombiningPass());
+    addExtensionsToPM(EP_Peephole, MPM);
     if (OptLevel > 1 && UseGVNAfterVectorization)
-      MPM.add(createGVNPass());                   // Remove redundancies
+      MPM.add(createGVNPass());           // Remove redundancies
     else
-      MPM.add(createEarlyCSEPass());              // Catch trivial redundancies
+      MPM.add(createEarlyCSEPass());      // Catch trivial redundancies
+
+    // BBVectorize may have significantly shortened a loop body; unroll again.
+    if (!DisableUnrollLoops)
+      MPM.add(createLoopUnrollPass());
   }
 
+  if (LoadCombine)
+    MPM.add(createLoadCombinePass());
+
   MPM.add(createAggressiveDCEPass());         // Delete dead instructions
-  MPM.add(createCFGSimplificationPass());     // Merge & remove BBs
+  MPM.add(createCFGSimplificationPass()); // Merge & remove BBs
   MPM.add(createInstructionCombiningPass());  // Clean up after everything.
+  addExtensionsToPM(EP_Peephole, 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());
+  MPM.add(createLoopVectorizePass(DisableUnrollLoops, LoopVectorize));
+  // 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
+  // as function calls, so that we can only pass them when the vectorizer
+  // changed the code.
+  MPM.add(createInstructionCombiningPass());
+  addExtensionsToPM(EP_Peephole, MPM);
+  MPM.add(createCFGSimplificationPass());
+
+  if (!DisableUnrollLoops)
+    MPM.add(createLoopUnrollPass());    // Unroll small loops
 
   if (!DisableUnitAtATime) {
     // FIXME: We shouldn't bother with this anymore.
@@ -232,7 +293,7 @@ void PassManagerBuilder::populateLTOPassManager(PassManagerBase &PM,
   // for a main function.  If main is defined, mark all other functions
   // internal.
   if (Internalize)
-    PM.add(createInternalizePass(true));
+    PM.add(createInternalizePass("main"));
 
   // Propagate constants at call sites into the functions they call.  This
   // opens opportunities for globalopt (and inlining) by substituting function
@@ -254,6 +315,7 @@ void PassManagerBuilder::populateLTOPassManager(PassManagerBase &PM,
   // function pointers.  When this happens, we often have to resolve varargs
   // calls, etc, so let instcombine do this.
   PM.add(createInstructionCombiningPass());
+  addExtensionsToPM(EP_Peephole, PM);
 
   // Inline small functions
   if (RunInliner)
@@ -272,7 +334,9 @@ void PassManagerBuilder::populateLTOPassManager(PassManagerBase &PM,
 
   // The IPO passes may leave cruft around.  Clean up after them.
   PM.add(createInstructionCombiningPass());
+  addExtensionsToPM(EP_Peephole, PM);
   PM.add(createJumpThreadingPass());
+
   // Break up allocas
   if (UseNewSROA)
     PM.add(createSROAPass());
@@ -284,13 +348,27 @@ void PassManagerBuilder::populateLTOPassManager(PassManagerBase &PM,
   PM.add(createGlobalsModRefPass()); // IP alias analysis.
 
   PM.add(createLICMPass());                 // Hoist loop invariants.
+  PM.add(createMergedLoadStoreMotionPass()); // Merge load/stores in diamonds
   PM.add(createGVNPass(DisableGVNLoadPRE)); // Remove redundancies.
   PM.add(createMemCpyOptPass());            // Remove dead memcpys.
+
   // Nuke dead stores.
   PM.add(createDeadStoreEliminationPass());
 
+  // More loops are countable; try to optimize them.
+  PM.add(createIndVarSimplifyPass());
+  PM.add(createLoopDeletionPass());
+  PM.add(createLoopVectorizePass(true, true));
+
+  // More scalar chains could be vectorized due to more alias information
+  PM.add(createSLPVectorizerPass()); // Vectorize parallel scalar chains.
+
+  if (LoadCombine)
+    PM.add(createLoadCombinePass());
+
   // Cleanup and simplify the code after the scalar optimizations.
   PM.add(createInstructionCombiningPass());
+  addExtensionsToPM(EP_Peephole, PM);
 
   PM.add(createJumpThreadingPass());
 
@@ -301,7 +379,15 @@ void PassManagerBuilder::populateLTOPassManager(PassManagerBase &PM,
   PM.add(createGlobalDCEPass());
 }
 
-LLVMPassManagerBuilderRef LLVMPassManagerBuilderCreate(void) {
+inline PassManagerBuilder *unwrap(LLVMPassManagerBuilderRef P) {
+    return reinterpret_cast<PassManagerBuilder*>(P);
+}
+
+inline LLVMPassManagerBuilderRef wrap(PassManagerBuilder *P) {
+  return reinterpret_cast<LLVMPassManagerBuilderRef>(P);
+}
+
+LLVMPassManagerBuilderRef LLVMPassManagerBuilderCreate() {
   PassManagerBuilder *PMB = new PassManagerBuilder();
   return wrap(PMB);
 }
@@ -342,8 +428,7 @@ LLVMPassManagerBuilderSetDisableUnrollLoops(LLVMPassManagerBuilderRef PMB,
 void
 LLVMPassManagerBuilderSetDisableSimplifyLibCalls(LLVMPassManagerBuilderRef PMB,
                                                  LLVMBool Value) {
-  PassManagerBuilder *Builder = unwrap(PMB);
-  Builder->DisableSimplifyLibCalls = Value;
+  // NOTE: The simplify-libcalls pass has been removed.
 }
 
 void
@@ -371,9 +456,9 @@ LLVMPassManagerBuilderPopulateModulePassManager(LLVMPassManagerBuilderRef PMB,
 
 void LLVMPassManagerBuilderPopulateLTOPassManager(LLVMPassManagerBuilderRef PMB,
                                                   LLVMPassManagerRef PM,
-                                                  bool Internalize,
-                                                  bool RunInliner) {
+                                                  LLVMBool Internalize,
+                                                  LLVMBool RunInliner) {
   PassManagerBuilder *Builder = unwrap(PMB);
   PassManagerBase *LPM = unwrap(PM);
-  Builder->populateLTOPassManager(*LPM, Internalize, RunInliner);
+  Builder->populateLTOPassManager(*LPM, Internalize != 0, RunInliner != 0);
 }