[PGO][PGSO] Instrument the code gen / target passes.

Summary:
Split off of D67120.

Add the profile guided size optimization instrumentation / queries in the code
gen or target passes. This doesn't enable the size optimizations in those passes
yet as they are currently disabled in shouldOptimizeForSize (for non-IR pass
queries).

A second try after reverted D71072.

Reviewers: davidxl

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71149

Author: hjyamauchi

llvm/include/llvm/CodeGen/AsmPrinter.h

@@ -48,6 +48,7 @@ class GlobalObject;
 class GlobalValue;
 class GlobalVariable;
 class MachineBasicBlock;
+class MachineBlockFrequencyInfo;
 class MachineConstantPoolValue;
 class MachineDominatorTree;
 class MachineFunction;
@@ -69,6 +70,7 @@ class MCSymbol;
 class MCTargetOptions;
 class MDNode;
 class Module;
+class ProfileSummaryInfo;
 class raw_ostream;
 class RemarkStreamer;
 class StackMaps;
@@ -108,6 +110,10 @@ class AsmPrinter : public MachineFunctionPass {
   /// Optimization remark emitter.
   MachineOptimizationRemarkEmitter *ORE;
 
+  MachineBlockFrequencyInfo *MBFI;
+
+  ProfileSummaryInfo *PSI;
+
   /// The symbol for the current function. This is recalculated at the beginning
   /// of each call to runOnMachineFunction().
   MCSymbol *CurrentFnSym = nullptr;

llvm/include/llvm/CodeGen/MachineOptimizationRemarkEmitter.h

@@ -182,6 +182,10 @@ class MachineOptimizationRemarkEmitter {
     }
   }
 
+  MachineBlockFrequencyInfo *getBFI() {
+    return MBFI;
+  }
+
 private:
   MachineFunction &MF;
 

llvm/include/llvm/CodeGen/TailDuplicator.h

@@ -25,11 +25,13 @@
 namespace llvm {
 
 class MachineBasicBlock;
+class MachineBlockFrequencyInfo;
 class MachineBranchProbabilityInfo;
 class MachineFunction;
 class MachineInstr;
 class MachineModuleInfo;
 class MachineRegisterInfo;
+class ProfileSummaryInfo;
 class TargetRegisterInfo;
 
 /// Utility class to perform tail duplication.
@@ -40,6 +42,8 @@ class TailDuplicator {
   const MachineModuleInfo *MMI;
   MachineRegisterInfo *MRI;
   MachineFunction *MF;
+  const MachineBlockFrequencyInfo *MBFI;
+  ProfileSummaryInfo *PSI;
   bool PreRegAlloc;
   bool LayoutMode;
   unsigned TailDupSize;
@@ -65,6 +69,8 @@ class TailDuplicator {
   ///     default implies using the command line value TailDupSize.
   void initMF(MachineFunction &MF, bool PreRegAlloc,
               const MachineBranchProbabilityInfo *MBPI,
+              const MachineBlockFrequencyInfo *MBFI,
+              ProfileSummaryInfo *PSI,
               bool LayoutMode, unsigned TailDupSize = 0);
 
   bool tailDuplicateBlocks();

llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp

@@ -31,13 +31,16 @@
 #include "llvm/Analysis/ConstantFolding.h"
 #include "llvm/Analysis/EHPersonalities.h"
 #include "llvm/Analysis/OptimizationRemarkEmitter.h"
+#include "llvm/Analysis/ProfileSummaryInfo.h"
 #include "llvm/BinaryFormat/COFF.h"
 #include "llvm/BinaryFormat/Dwarf.h"
 #include "llvm/BinaryFormat/ELF.h"
 #include "llvm/CodeGen/GCMetadata.h"
 #include "llvm/CodeGen/GCMetadataPrinter.h"
 #include "llvm/CodeGen/GCStrategy.h"
+#include "llvm/CodeGen/LazyMachineBlockFrequencyInfo.h"
 #include "llvm/CodeGen/MachineBasicBlock.h"
+#include "llvm/CodeGen/MachineBlockFrequencyInfo.h"
 #include "llvm/CodeGen/MachineConstantPool.h"
 #include "llvm/CodeGen/MachineDominators.h"
 #include "llvm/CodeGen/MachineFrameInfo.h"
@@ -52,6 +55,7 @@
 #include "llvm/CodeGen/MachineModuleInfoImpls.h"
 #include "llvm/CodeGen/MachineOperand.h"
 #include "llvm/CodeGen/MachineOptimizationRemarkEmitter.h"
+#include "llvm/CodeGen/MachineSizeOpts.h"
 #include "llvm/CodeGen/StackMaps.h"
 #include "llvm/CodeGen/TargetFrameLowering.h"
 #include "llvm/CodeGen/TargetInstrInfo.h"
@@ -248,6 +252,8 @@ void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
   AU.addRequired<MachineModuleInfoWrapperPass>();
   AU.addRequired<MachineOptimizationRemarkEmitterPass>();
   AU.addRequired<GCModuleInfo>();
+  AU.addRequired<LazyMachineBlockFrequencyInfoPass>();
+  AU.addRequired<ProfileSummaryInfoWrapperPass>();
 }
 
 bool AsmPrinter::doInitialization(Module &M) {
@@ -1684,6 +1690,13 @@ void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
   }
 
   ORE = &getAnalysis<MachineOptimizationRemarkEmitterPass>().getORE();
+  PSI = &getAnalysis<ProfileSummaryInfoWrapperPass>().getPSI();
+  MBFI = (PSI && PSI->hasProfileSummary()) ?
+         // ORE conditionally computes MBFI. If available, use it, otherwise
+         // request it.
+         (ORE->getBFI() ? ORE->getBFI() :
+          &getAnalysis<LazyMachineBlockFrequencyInfoPass>().getBFI()) :
+         nullptr;
 }
 
 namespace {
@@ -2913,8 +2926,10 @@ static void emitBasicBlockLoopComments(const MachineBasicBlock &MBB,
 void AsmPrinter::setupCodePaddingContext(const MachineBasicBlock &MBB,
                                          MCCodePaddingContext &Context) const {
   assert(MF != nullptr && "Machine function must be valid");
+  bool OptForSize = MF->getFunction().hasOptSize() ||
+                    llvm::shouldOptimizeForSize(&MBB, PSI, MBFI);
   Context.IsPaddingActive = !MF->hasInlineAsm() &&
-                            !MF->getFunction().hasOptSize() &&
+                            !OptForSize &&
                             TM.getOptLevel() != CodeGenOpt::None;
   Context.IsBasicBlockReachableViaFallthrough =
       std::find(MBB.pred_begin(), MBB.pred_end(), MBB.getPrevNode()) !=

llvm/lib/CodeGen/BranchFolding.cpp

@@ -24,6 +24,7 @@
 #include "llvm/ADT/SmallSet.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/Statistic.h"
+#include "llvm/Analysis/ProfileSummaryInfo.h"
 #include "llvm/CodeGen/Analysis.h"
 #include "llvm/CodeGen/LivePhysRegs.h"
 #include "llvm/CodeGen/MachineBasicBlock.h"
@@ -38,6 +39,7 @@
 #include "llvm/CodeGen/MachineModuleInfo.h"
 #include "llvm/CodeGen/MachineOperand.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/CodeGen/MachineSizeOpts.h"
 #include "llvm/CodeGen/TargetInstrInfo.h"
 #include "llvm/CodeGen/TargetOpcodes.h"
 #include "llvm/CodeGen/TargetPassConfig.h"
@@ -103,6 +105,7 @@ namespace {
     void getAnalysisUsage(AnalysisUsage &AU) const override {
       AU.addRequired<MachineBlockFrequencyInfo>();
       AU.addRequired<MachineBranchProbabilityInfo>();
+      AU.addRequired<ProfileSummaryInfoWrapperPass>();
       AU.addRequired<TargetPassConfig>();
       MachineFunctionPass::getAnalysisUsage(AU);
     }
@@ -129,7 +132,8 @@ bool BranchFolderPass::runOnMachineFunction(MachineFunction &MF) {
   BranchFolder::MBFIWrapper MBBFreqInfo(
       getAnalysis<MachineBlockFrequencyInfo>());
   BranchFolder Folder(EnableTailMerge, /*CommonHoist=*/true, MBBFreqInfo,
-                      getAnalysis<MachineBranchProbabilityInfo>());
+                      getAnalysis<MachineBranchProbabilityInfo>(),
+                      &getAnalysis<ProfileSummaryInfoWrapperPass>().getPSI());
   auto *MMIWP = getAnalysisIfAvailable<MachineModuleInfoWrapperPass>();
   return Folder.OptimizeFunction(
       MF, MF.getSubtarget().getInstrInfo(), MF.getSubtarget().getRegisterInfo(),
@@ -139,9 +143,10 @@ bool BranchFolderPass::runOnMachineFunction(MachineFunction &MF) {
 BranchFolder::BranchFolder(bool defaultEnableTailMerge, bool CommonHoist,
                            MBFIWrapper &FreqInfo,
                            const MachineBranchProbabilityInfo &ProbInfo,
+                           ProfileSummaryInfo *PSI,
                            unsigned MinTailLength)
     : EnableHoistCommonCode(CommonHoist), MinCommonTailLength(MinTailLength),
-      MBBFreqInfo(FreqInfo), MBPI(ProbInfo) {
+      MBBFreqInfo(FreqInfo), MBPI(ProbInfo), PSI(PSI) {
   if (MinCommonTailLength == 0)
     MinCommonTailLength = TailMergeSize;
   switch (FlagEnableTailMerge) {
@@ -585,7 +590,9 @@ ProfitableToMerge(MachineBasicBlock *MBB1, MachineBasicBlock *MBB2,
                   MachineBasicBlock::iterator &I2, MachineBasicBlock *SuccBB,
                   MachineBasicBlock *PredBB,
                   DenseMap<const MachineBasicBlock *, int> &EHScopeMembership,
-                  bool AfterPlacement) {
+                  bool AfterPlacement,
+                  BranchFolder::MBFIWrapper &MBBFreqInfo,
+                  ProfileSummaryInfo *PSI) {
   // It is never profitable to tail-merge blocks from two different EH scopes.
   if (!EHScopeMembership.empty()) {
     auto EHScope1 = EHScopeMembership.find(MBB1);
@@ -682,7 +689,11 @@ ProfitableToMerge(MachineBasicBlock *MBB1, MachineBasicBlock *MBB2,
   // branch instruction, which is likely to be smaller than the 2
   // instructions that would be deleted in the merge.
   MachineFunction *MF = MBB1->getParent();
-  return EffectiveTailLen >= 2 && MF->getFunction().hasOptSize() &&
+  bool OptForSize =
+      MF->getFunction().hasOptSize() ||
+      (llvm::shouldOptimizeForSize(MBB1, PSI, &MBBFreqInfo.getMBFI()) &&
+       llvm::shouldOptimizeForSize(MBB2, PSI, &MBBFreqInfo.getMBFI()));
+  return EffectiveTailLen >= 2 && OptForSize &&
          (FullBlockTail1 || FullBlockTail2);
 }
 
@@ -704,7 +715,7 @@ unsigned BranchFolder::ComputeSameTails(unsigned CurHash,
                             CommonTailLen, TrialBBI1, TrialBBI2,
                             SuccBB, PredBB,
                             EHScopeMembership,
-                            AfterBlockPlacement)) {
+                            AfterBlockPlacement, MBBFreqInfo, PSI)) {
         if (CommonTailLen > maxCommonTailLength) {
           SameTails.clear();
           maxCommonTailLength = CommonTailLen;
@@ -1534,8 +1545,10 @@ bool BranchFolder::OptimizeBlock(MachineBasicBlock *MBB) {
     }
   }
 
-  if (!IsEmptyBlock(MBB) && MBB->pred_size() == 1 &&
-      MF.getFunction().hasOptSize()) {
+  bool OptForSize =
+      MF.getFunction().hasOptSize() ||
+      llvm::shouldOptimizeForSize(MBB, PSI, &MBBFreqInfo.getMBFI());
+  if (!IsEmptyBlock(MBB) && MBB->pred_size() == 1 && OptForSize) {
     // Changing "Jcc foo; foo: jmp bar;" into "Jcc bar;" might change the branch
     // direction, thereby defeating careful block placement and regressing
     // performance. Therefore, only consider this for optsize functions.

llvm/lib/CodeGen/BranchFolding.h

@@ -27,6 +27,7 @@ class MachineFunction;
 class MachineLoopInfo;
 class MachineModuleInfo;
 class MachineRegisterInfo;
+class ProfileSummaryInfo;
 class raw_ostream;
 class TargetInstrInfo;
 class TargetRegisterInfo;
@@ -39,6 +40,7 @@ class TargetRegisterInfo;
                           bool CommonHoist,
                           MBFIWrapper &FreqInfo,
                           const MachineBranchProbabilityInfo &ProbInfo,
+                          ProfileSummaryInfo *PSI,
                           // Min tail length to merge. Defaults to commandline
                           // flag. Ignored for optsize.
                           unsigned MinTailLength = 0);
@@ -145,6 +147,7 @@ class TargetRegisterInfo;
                                   const BlockFrequency Freq) const;
       void view(const Twine &Name, bool isSimple = true);
       uint64_t getEntryFreq() const;
+      const MachineBlockFrequencyInfo &getMBFI() { return MBFI; }
 
     private:
       const MachineBlockFrequencyInfo &MBFI;
@@ -154,6 +157,7 @@ class TargetRegisterInfo;
   private:
     MBFIWrapper &MBBFreqInfo;
     const MachineBranchProbabilityInfo &MBPI;
+    ProfileSummaryInfo *PSI;
 
     bool TailMergeBlocks(MachineFunction &MF);
     bool TryTailMergeBlocks(MachineBasicBlock* SuccBB,