Part one of switching to using a more sane heuristic for determining if-conversion...

[oota-llvm.git] / lib / CodeGen / IfConversion.cpp

diff --git a/lib/CodeGen/IfConversion.cpp b/lib/CodeGen/IfConversion.cpp
index 6c064a74cd048a31cde9f7ab14b00f4e5214c4f7..c9c56dd86d226d28938ef06c3d57a4a7b777216e 100644 (file)
--- a/lib/CodeGen/IfConversion.cpp
+++ b/lib/CodeGen/IfConversion.cpp
@@ -18,6 +18,7 @@
 #include "llvm/CodeGen/MachineModuleInfo.h"
 #include "llvm/CodeGen/MachineFunctionPass.h"
 #include "llvm/Target/TargetInstrInfo.h"
+#include "llvm/Target/TargetInstrItineraries.h"
 #include "llvm/Target/TargetLowering.h"
 #include "llvm/Target/TargetMachine.h"
 #include "llvm/Target/TargetRegisterInfo.h"
@@ -150,11 +151,12 @@ namespace {
     const TargetLowering *TLI;
     const TargetInstrInfo *TII;
     const TargetRegisterInfo *TRI;
+    const InstrItineraryData *InstrItins;
     bool MadeChange;
     int FnNum;
   public:
     static char ID;
-    IfConverter() : MachineFunctionPass(&ID), FnNum(-1) {}
+    IfConverter() : MachineFunctionPass(ID), FnNum(-1) {}
 
     virtual bool runOnMachineFunction(MachineFunction &MF);
     virtual const char *getPassName() const { return "If Converter"; }
@@ -189,13 +191,13 @@ namespace {
     void MergeBlocks(BBInfo &ToBBI, BBInfo &FromBBI, bool AddEdges = true);
 
     bool MeetIfcvtSizeLimit(MachineBasicBlock &BB, unsigned Size) const {
-      return Size > 0 && TII->isProfitableToIfCvt(BB, Size);
+      return Size > 0 && TII->isProfitableToIfCvt(BB, Size, 0.5);
     }
 
     bool MeetIfcvtSizeLimit(MachineBasicBlock &TBB, unsigned TSize,
                             MachineBasicBlock &FBB, unsigned FSize) const {
       return TSize > 0 && FSize > 0 &&
-        TII->isProfitableToIfCvt(TBB, TSize, FBB, FSize);
+        TII->isProfitableToIfCvt(TBB, TSize, FBB, FSize, 0.5);
     }
 
     // blockAlwaysFallThrough - Block ends without a terminator.
@@ -238,6 +240,7 @@ bool IfConverter::runOnMachineFunction(MachineFunction &MF) {
   TLI = MF.getTarget().getTargetLowering();
   TII = MF.getTarget().getInstrInfo();
   TRI = MF.getTarget().getRegisterInfo();
+  InstrItins = MF.getTarget().getInstrItineraryData();
   if (!TII) return false;
 
   // Tail merge tend to expose more if-conversion opportunities.
@@ -441,7 +444,7 @@ bool IfConverter::ValidSimple(BBInfo &TrueBBI, unsigned &Dups) const {
 
   if (TrueBBI.BB->pred_size() > 1) {
     if (TrueBBI.CannotBeCopied ||
-        !TII->isProfitableToDupForIfCvt(*TrueBBI.BB, TrueBBI.NonPredSize))
+        !TII->isProfitableToDupForIfCvt(*TrueBBI.BB, TrueBBI.NonPredSize, 0.5))
       return false;
     Dups = TrueBBI.NonPredSize;
   }
@@ -478,7 +481,7 @@ bool IfConverter::ValidTriangle(BBInfo &TrueBBI, BBInfo &FalseBBI,
           ++Size;
       }
     }
-    if (!TII->isProfitableToDupForIfCvt(*TrueBBI.BB, Size))
+    if (!TII->isProfitableToDupForIfCvt(*TrueBBI.BB, Size, 0.5))
       return false;
     Dups = Size;
   }
@@ -641,9 +644,10 @@ void IfConverter::ScanInstructions(BBInfo &BBI) {
     bool isCondBr = BBI.IsBrAnalyzable && TID.isConditionalBranch();
 
     if (!isCondBr) {
-      if (!isPredicated)
-        BBI.NonPredSize++;
-      else if (!AlreadyPredicated) {
+      if (!isPredicated) {
+        unsigned NumOps = TII->getNumMicroOps(&*I, InstrItins);
+        BBI.NonPredSize += NumOps;
+      } else if (!AlreadyPredicated) {
         // FIXME: This instruction is already predicated before the
         // if-conversion pass. It's probably something like a conditional move.
         // Mark this block unpredicable for now.
@@ -1364,7 +1368,8 @@ void IfConverter::CopyAndPredicateBlock(BBInfo &ToBBI, BBInfo &FromBBI,
 
     MachineInstr *MI = MF.CloneMachineInstr(I);
     ToBBI.BB->insert(ToBBI.BB->end(), MI);
-    ToBBI.NonPredSize++;
+    unsigned NumOps = TII->getNumMicroOps(MI, InstrItins);
+    ToBBI.NonPredSize += NumOps;
 
     if (!TII->isPredicated(I) && !MI->isDebugValue()) {
       if (!TII->PredicateInstruction(MI, Cond)) {