[PGO][PGSO] SizeOpts changes.

Summary:
(Split of off D67120)

SizeOpts/MachineSizeOpts changes for profile guided size optimization.

Reviewers: davidxl

Subscribers: mgorny, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69070

llvm-svn: 375254

5 files changed, 139 insertions, 3 deletions

diff --git a/llvm/lib/CodeGen/CMakeLists.txt b/llvm/lib/CodeGen/CMakeLists.txt
index 50b469d6d93..f5c18f89fa0 100644
--- a/llvm/lib/CodeGen/CMakeLists.txt
+++ b/llvm/lib/CodeGen/CMakeLists.txt
@@ -92,6 +92,7 @@ add_llvm_library(LLVMCodeGen
   MachineRegisterInfo.cpp
   MachineScheduler.cpp
   MachineSink.cpp
+  MachineSizeOpts.cpp
   MachineSSAUpdater.cpp
   MachineTraceMetrics.cpp
   MachineVerifier.cpp
diff --git a/llvm/lib/CodeGen/MachineBlockFrequencyInfo.cpp b/llvm/lib/CodeGen/MachineBlockFrequencyInfo.cpp
index 53a35b7e89c..889fde606a4 100644
--- a/llvm/lib/CodeGen/MachineBlockFrequencyInfo.cpp
+++ b/llvm/lib/CodeGen/MachineBlockFrequencyInfo.cpp
@@ -172,6 +172,13 @@ MachineBlockFrequencyInfo::MachineBlockFrequencyInfo()
   initializeMachineBlockFrequencyInfoPass(*PassRegistry::getPassRegistry());
 }
 
+MachineBlockFrequencyInfo::MachineBlockFrequencyInfo(
+      MachineFunction &F,
+      MachineBranchProbabilityInfo &MBPI,
+      MachineLoopInfo &MLI) : MachineFunctionPass(ID) {
+  calculate(F, MBPI, MLI);
+}
+
 MachineBlockFrequencyInfo::~MachineBlockFrequencyInfo() = default;
 
 void MachineBlockFrequencyInfo::getAnalysisUsage(AnalysisUsage &AU) const {
diff --git a/llvm/lib/CodeGen/MachineDominators.cpp b/llvm/lib/CodeGen/MachineDominators.cpp
index 706c706d752..0d57bca37d9 100644
--- a/llvm/lib/CodeGen/MachineDominators.cpp
+++ b/llvm/lib/CodeGen/MachineDominators.cpp
@@ -49,11 +49,15 @@ void MachineDominatorTree::getAnalysisUsage(AnalysisUsage &AU) const {
 }
 
 bool MachineDominatorTree::runOnMachineFunction(MachineFunction &F) {
+  calculate(F);
+  return false;
+}
+
+void MachineDominatorTree::calculate(MachineFunction &F) {
   CriticalEdgesToSplit.clear();
   NewBBs.clear();
   DT.reset(new DomTreeBase<MachineBasicBlock>());
   DT->recalculate(F);
-  return false;
 }
 
 MachineDominatorTree::MachineDominatorTree()
diff --git a/llvm/lib/CodeGen/MachineLoopInfo.cpp b/llvm/lib/CodeGen/MachineLoopInfo.cpp
index 3b8b430d1b0..85822a67149 100644
--- a/llvm/lib/CodeGen/MachineLoopInfo.cpp
+++ b/llvm/lib/CodeGen/MachineLoopInfo.cpp
@@ -36,11 +36,15 @@ INITIALIZE_PASS_END(MachineLoopInfo, "machine-loops",
 char &llvm::MachineLoopInfoID = MachineLoopInfo::ID;
 
 bool MachineLoopInfo::runOnMachineFunction(MachineFunction &) {
-  releaseMemory();
-  LI.analyze(getAnalysis<MachineDominatorTree>().getBase());
+  calculate(getAnalysis<MachineDominatorTree>());
   return false;
 }
 
+void MachineLoopInfo::calculate(MachineDominatorTree &MDT) {
+  releaseMemory();
+  LI.analyze(MDT.getBase());
+}
+
 void MachineLoopInfo::getAnalysisUsage(AnalysisUsage &AU) const {
   AU.setPreservesAll();
   AU.addRequired<MachineDominatorTree>();
diff --git a/llvm/lib/CodeGen/MachineSizeOpts.cpp b/llvm/lib/CodeGen/MachineSizeOpts.cpp
new file mode 100644
index 00000000000..0c2ef3321e0
--- /dev/null
+++ b/llvm/lib/CodeGen/MachineSizeOpts.cpp
@@ -0,0 +1,120 @@
+//===- MachineSizeOpts.cpp - code size optimization related code ----------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains some shared machine IR code size optimization related
+// code.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CodeGen/MachineSizeOpts.h"
+#include "llvm/Analysis/ProfileSummaryInfo.h"
+#include "llvm/CodeGen/MachineBlockFrequencyInfo.h"
+
+using namespace llvm;
+
+extern cl::opt<bool> EnablePGSO;
+extern cl::opt<bool> PGSOLargeWorkingSetSizeOnly;
+extern cl::opt<bool> ForcePGSO;
+extern cl::opt<int> PgsoCutoffInstrProf;
+extern cl::opt<int> PgsoCutoffSampleProf;
+
+namespace machine_size_opts_detail {
+
+/// Like ProfileSummaryInfo::isColdBlock but for MachineBasicBlock.
+bool isColdBlock(const MachineBasicBlock *MBB,
+                 ProfileSummaryInfo *PSI,
+                 const MachineBlockFrequencyInfo *MBFI) {
+  auto Count = MBFI->getBlockProfileCount(MBB);
+  return Count && PSI->isColdCount(*Count);
+}
+
+/// Like ProfileSummaryInfo::isHotBlockNthPercentile but for MachineBasicBlock.
+static bool isHotBlockNthPercentile(int PercentileCutoff,
+                                    const MachineBasicBlock *MBB,
+                                    ProfileSummaryInfo *PSI,
+                                    const MachineBlockFrequencyInfo *MBFI) {
+  auto Count = MBFI->getBlockProfileCount(MBB);
+  return Count && PSI->isHotCountNthPercentile(PercentileCutoff, *Count);
+}
+
+/// Like ProfileSummaryInfo::isFunctionColdInCallGraph but for
+/// MachineFunction.
+bool isFunctionColdInCallGraph(
+    const MachineFunction *MF,
+    ProfileSummaryInfo *PSI,
+    const MachineBlockFrequencyInfo &MBFI) {
+  if (auto FunctionCount = MF->getFunction().getEntryCount())
+    if (!PSI->isColdCount(FunctionCount.getCount()))
+      return false;
+  for (const auto &MBB : *MF)
+    if (!isColdBlock(&MBB, PSI, &MBFI))
+      return false;
+  return true;
+}
+
+/// Like ProfileSummaryInfo::isFunctionHotInCallGraphNthPercentile but for
+/// MachineFunction.
+bool isFunctionHotInCallGraphNthPercentile(
+    int PercentileCutoff,
+    const MachineFunction *MF,
+    ProfileSummaryInfo *PSI,
+    const MachineBlockFrequencyInfo &MBFI) {
+  if (auto FunctionCount = MF->getFunction().getEntryCount())
+    if (PSI->isHotCountNthPercentile(PercentileCutoff,
+                                     FunctionCount.getCount()))
+      return true;
+  for (const auto &MBB : *MF)
+    if (isHotBlockNthPercentile(PercentileCutoff, &MBB, PSI, &MBFI))
+      return true;
+  return false;
+}
+} // namespace machine_size_opts_detail
+
+namespace {
+struct MachineBasicBlockBFIAdapter {
+  static bool isFunctionColdInCallGraph(const MachineFunction *MF,
+                                        ProfileSummaryInfo *PSI,
+                                        const MachineBlockFrequencyInfo &MBFI) {
+    return machine_size_opts_detail::isFunctionColdInCallGraph(MF, PSI, MBFI);
+  }
+  static bool isFunctionHotInCallGraphNthPercentile(
+      int CutOff,
+      const MachineFunction *MF,
+      ProfileSummaryInfo *PSI,
+      const MachineBlockFrequencyInfo &MBFI) {
+    return machine_size_opts_detail::isFunctionHotInCallGraphNthPercentile(
+        CutOff, MF, PSI, MBFI);
+  }
+  static bool isColdBlock(const MachineBasicBlock *MBB,
+                          ProfileSummaryInfo *PSI,
+                          const MachineBlockFrequencyInfo *MBFI) {
+    return machine_size_opts_detail::isColdBlock(MBB, PSI, MBFI);
+  }
+  static bool isHotBlockNthPercentile(int CutOff,
+                                      const MachineBasicBlock *MBB,
+                                      ProfileSummaryInfo *PSI,
+                                      const MachineBlockFrequencyInfo *MBFI) {
+    return machine_size_opts_detail::isHotBlockNthPercentile(
+        CutOff, MBB, PSI, MBFI);
+  }
+};
+} // end anonymous namespace
+
+bool llvm::shouldOptimizeForSize(const MachineFunction *MF,
+                                 ProfileSummaryInfo *PSI,
+                                 const MachineBlockFrequencyInfo *MBFI) {
+  return shouldFuncOptimizeForSizeImpl<MachineBasicBlockBFIAdapter>(
+      MF, PSI, MBFI);
+}
+
+bool llvm::shouldOptimizeForSize(const MachineBasicBlock *MBB,
+                                 ProfileSummaryInfo *PSI,
+                                 const MachineBlockFrequencyInfo *MBFI) {
+  return shouldOptimizeForSizeImpl<MachineBasicBlockBFIAdapter>(
+      MBB, PSI, MBFI);
+}