[PGO][PGSO] SizeOpts changes.

Summary:
(Split of off D67120)

SizeOpts/MachineSizeOpts changes for profile guided size optimization.

(A second try after previously committed as r375254 and reverted as r375375.)

Subscribers: mgorny, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69409

1 files changed, 120 insertions, 0 deletions

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);
+}