misched: remove the unused getSpecialAddressLatency hook.
authorAndrew Trick <atrick@apple.com>
Mon, 8 Oct 2012 18:54:00 +0000 (18:54 +0000)
committerAndrew Trick <atrick@apple.com>
Mon, 8 Oct 2012 18:54:00 +0000 (18:54 +0000)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165418 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/Target/TargetSubtargetInfo.h
lib/CodeGen/ScheduleDAGInstrs.cpp
lib/Target/X86/X86Subtarget.cpp
lib/Target/X86/X86Subtarget.h

index 08c78f256411b9a613e2314937567cbdde50daac..6db96d980b5ebb9ffe7e5771f0cd0673350f4f87 100644 (file)
@@ -54,12 +54,6 @@ public:
     return 0;
   }
 
-  /// getSpecialAddressLatency - For targets where it is beneficial to
-  /// backschedule instructions that compute addresses, return a value
-  /// indicating the number of scheduling cycles of backscheduling that
-  /// should be attempted.
-  virtual unsigned getSpecialAddressLatency() const { return 0; }
-
   // enablePostRAScheduler - If the target can benefit from post-regalloc
   // scheduling and the specified optimization level meets the requirement
   // return true to enable post-register-allocation scheduling. In
index 9e82dc629d836059a46d7518a039dbaa193a9cc6..ad0bad22aa4fe57e9f3b29a26a530845e4678cdc 100644 (file)
@@ -238,8 +238,6 @@ void ScheduleDAGInstrs::addPhysRegDataDeps(SUnit *SU, unsigned OperIdx) {
 
   // Ask the target if address-backscheduling is desirable, and if so how much.
   const TargetSubtargetInfo &ST = TM.getSubtarget<TargetSubtargetInfo>();
-  unsigned SpecialAddressLatency = ST.getSpecialAddressLatency();
-  unsigned DataLatency = SU->Latency;
 
   for (MCRegAliasIterator Alias(MO.getReg(), TRI, true);
        Alias.isValid(); ++Alias) {
@@ -250,29 +248,13 @@ void ScheduleDAGInstrs::addPhysRegDataDeps(SUnit *SU, unsigned OperIdx) {
       SUnit *UseSU = UseList[i].SU;
       if (UseSU == SU)
         continue;
-      MachineInstr *UseMI = UseSU->getInstr();
+
+      SDep dep(SU, SDep::Data, 1, *Alias);
+
+      // Adjust the dependence latency using operand def/use information,
+      // then allow the target to perform its own adjustments.
       int UseOp = UseList[i].OpIdx;
-      unsigned LDataLatency = DataLatency;
-      // Optionally add in a special extra latency for nodes that
-      // feed addresses.
-      // TODO: Perhaps we should get rid of
-      // SpecialAddressLatency and just move this into
-      // adjustSchedDependency for the targets that care about it.
-      if (SpecialAddressLatency != 0 && UseSU != &ExitSU) {
-        const MCInstrDesc &UseMCID = UseMI->getDesc();
-        int RegUseIndex = UseMI->findRegisterUseOperandIdx(*Alias);
-        assert(RegUseIndex >= 0 && "UseMI doesn't use register!");
-        if (RegUseIndex >= 0 &&
-            (UseMI->mayLoad() || UseMI->mayStore()) &&
-            (unsigned)RegUseIndex < UseMCID.getNumOperands() &&
-            UseMCID.OpInfo[RegUseIndex].isLookupPtrRegClass())
-          LDataLatency += SpecialAddressLatency;
-      }
-      // Adjust the dependence latency using operand def/use
-      // information (if any), and then allow the target to
-      // perform its own adjustments.
-      SDep dep(SU, SDep::Data, LDataLatency, *Alias);
-      MachineInstr *RegUse = UseOp < 0 ? 0 : UseMI;
+      MachineInstr *RegUse = UseOp < 0 ? 0 : UseSU->getInstr();
       dep.setLatency(
         SchedModel.computeOperandLatency(SU->getInstr(), OperIdx,
                                          RegUse, UseOp, /*FindMin=*/false));
@@ -346,9 +328,6 @@ void ScheduleDAGInstrs::addPhysRegDeps(SUnit *SU, unsigned OperIdx) {
         const MachineInstr *UseMI = UseMO->getParent();
         unsigned UseMOIdx = UseMO - &UseMI->getOperand(0);
         const MCInstrDesc &UseMCID = UseMI->getDesc();
-        const TargetSubtargetInfo &ST =
-          TM.getSubtarget<TargetSubtargetInfo>();
-        unsigned SpecialAddressLatency = ST.getSpecialAddressLatency();
         // TODO: If we knew the total depth of the region here, we could
         // handle the case where the whole loop is inside the region but
         // is large enough that the isScheduleHigh trick isn't needed.
@@ -358,8 +337,6 @@ void ScheduleDAGInstrs::addPhysRegDeps(SUnit *SU, unsigned OperIdx) {
           // the same region by checking to see if it has the same parent.
           if (UseMI->getParent() != MI->getParent()) {
             unsigned Latency = SU->Latency;
-            if (UseMCID.OpInfo[UseMOIdx].isLookupPtrRegClass())
-              Latency += SpecialAddressLatency;
             // This is a wild guess as to the portion of the latency which
             // will be overlapped by work done outside the current
             // scheduling region.
@@ -369,14 +346,6 @@ void ScheduleDAGInstrs::addPhysRegDeps(SUnit *SU, unsigned OperIdx) {
                                 /*Reg=*/0, /*isNormalMemory=*/false,
                                 /*isMustAlias=*/false,
                                 /*isArtificial=*/true));
-          } else if (SpecialAddressLatency > 0 &&
-                     UseMCID.OpInfo[UseMOIdx].isLookupPtrRegClass()) {
-            // The entire loop body is within the current scheduling region
-            // and the latency of this operation is assumed to be greater
-            // than the latency of the loop.
-            // TODO: Recursively mark data-edge predecessors as
-            //       isScheduleHigh too.
-            SU->isScheduleHigh = true;
           }
         }
         LoopRegs.Deps.erase(I);
@@ -465,9 +434,7 @@ void ScheduleDAGInstrs::addVRegUseDeps(SUnit *SU, unsigned OperIdx) {
     if (DefSU) {
       // The reaching Def lives within this scheduling region.
       // Create a data dependence.
-      //
-      // TODO: Handle "special" address latencies cleanly.
-      SDep dep(DefSU, SDep::Data, DefSU->Latency, Reg);
+      SDep dep(DefSU, SDep::Data, 1, Reg);
       // Adjust the dependence latency using operand def/use information, then
       // allow the target to perform its own adjustments.
       int DefOp = Def->findRegisterDefOperandIdx(Reg);
index 24b551d21ce7bc4afc9efbf5fe28d999170adda2..4130637a653ea80d5382494dca8fa23d2dbd1b3b 100644 (file)
@@ -163,17 +163,6 @@ bool X86Subtarget::IsLegalToCallImmediateAddr(const TargetMachine &TM) const {
   return isTargetELF() || TM.getRelocationModel() == Reloc::Static;
 }
 
-/// getSpecialAddressLatency - For targets where it is beneficial to
-/// backschedule instructions that compute addresses, return a value
-/// indicating the number of scheduling cycles of backscheduling that
-/// should be attempted.
-unsigned X86Subtarget::getSpecialAddressLatency() const {
-  // For x86 out-of-order targets, back-schedule address computations so
-  // that loads and stores aren't blocked.
-  // This value was chosen arbitrarily.
-  return 200;
-}
-
 void X86Subtarget::AutoDetectSubtargetFeatures() {
   unsigned EAX = 0, EBX = 0, ECX = 0, EDX = 0;
   unsigned MaxLevel;
index f723c66b729cc9a1e482684c26b37a53be7a3039..3a990fc5deb5f2a3a856fac7344c19405dfac523 100644 (file)
@@ -305,12 +305,6 @@ public:
   /// returns null.
   const char *getBZeroEntry() const;
 
-  /// getSpecialAddressLatency - For targets where it is beneficial to
-  /// backschedule instructions that compute addresses, return a value
-  /// indicating the number of scheduling cycles of backscheduling that
-  /// should be attempted.
-  unsigned getSpecialAddressLatency() const;
-
   /// enablePostRAScheduler - run for Atom optimization.
   bool enablePostRAScheduler(CodeGenOpt::Level OptLevel,
                              TargetSubtargetInfo::AntiDepBreakMode& Mode,