[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

1 files changed, 12 insertions, 5 deletions

diff --git a/llvm/lib/CodeGen/TailDuplicator.cpp b/llvm/lib/CodeGen/TailDuplicator.cpp
index 03c68a37e45..cd1278fd4d8 100644
--- a/llvm/lib/CodeGen/TailDuplicator.cpp
+++ b/llvm/lib/CodeGen/TailDuplicator.cpp
@@ -19,13 +19,16 @@
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/Statistic.h"
+#include "llvm/Analysis/ProfileSummaryInfo.h"
 #include "llvm/CodeGen/MachineBasicBlock.h"
 #include "llvm/CodeGen/MachineBranchProbabilityInfo.h"
+#include "llvm/CodeGen/MachineBlockFrequencyInfo.h"
 #include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/CodeGen/MachineInstr.h"
 #include "llvm/CodeGen/MachineInstrBuilder.h"
 #include "llvm/CodeGen/MachineOperand.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/CodeGen/MachineSizeOpts.h"
 #include "llvm/CodeGen/MachineSSAUpdater.h"
 #include "llvm/CodeGen/TargetInstrInfo.h"
 #include "llvm/CodeGen/TargetRegisterInfo.h"
@@ -77,6 +80,8 @@ static cl::opt<unsigned> TailDupLimit("tail-dup-limit", cl::init(~0U),
 
 void TailDuplicator::initMF(MachineFunction &MFin, bool PreRegAlloc,
                             const MachineBranchProbabilityInfo *MBPIin,
+                            const MachineBlockFrequencyInfo *MBFIin,
+                            ProfileSummaryInfo *PSIin,
                             bool LayoutModeIn, unsigned TailDupSizeIn) {
   MF = &MFin;
   TII = MF->getSubtarget().getInstrInfo();
@@ -84,6 +89,8 @@ void TailDuplicator::initMF(MachineFunction &MFin, bool PreRegAlloc,
   MRI = &MF->getRegInfo();
   MMI = &MF->getMMI();
   MBPI = MBPIin;
+  MBFI = MBFIin;
+  PSI = PSIin;
   TailDupSize = TailDupSizeIn;
 
   assert(MBPI != nullptr && "Machine Branch Probability Info required");
@@ -555,14 +562,14 @@ bool TailDuplicator::shouldTailDuplicate(bool IsSimple,
   // duplicate only one, because one branch instruction can be eliminated to
   // compensate for the duplication.
   unsigned MaxDuplicateCount;
-  if (TailDupSize == 0 &&
-      TailDuplicateSize.getNumOccurrences() == 0 &&
-      MF->getFunction().hasOptSize())
-    MaxDuplicateCount = 1;
-  else if (TailDupSize == 0)
+  bool OptForSize = MF->getFunction().hasOptSize() ||
+                    llvm::shouldOptimizeForSize(&TailBB, PSI, MBFI);
+  if (TailDupSize == 0)
     MaxDuplicateCount = TailDuplicateSize;
   else
     MaxDuplicateCount = TailDupSize;
+  if (OptForSize)
+    MaxDuplicateCount = 1;
 
   // If the block to be duplicated ends in an unanalyzable fallthrough, don't
   // duplicate it.