[llvm-commits] [llvm] r56290 - in /llvm/trunk: include/llvm/CodeGen/LiveIntervalAnalysis.h include/llvm/CodeGen/MachineOperand.h include/llvm/CodeGen/ScheduleDAG.h lib/CodeGen/AsmPrinter/AsmPrinter.cpp lib/CodeGen/LiveIntervalAnalysis.cpp lib/CodeGen/MachineInstr.cpp lib/CodeGen/RegAllocLinearScan.cpp lib/CodeGen/SelectionDAG/ScheduleDAGEmit.cpp lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp test/CodeGen/X86/2008-09-17-inline-asm-1.ll

Dale Johannesen dalej at apple.com
Wed Sep 17 14:13:12 PDT 2008


Author: johannes
Date: Wed Sep 17 16:13:11 2008
New Revision: 56290

URL: http://llvm.org/viewvc/llvm-project?rev=56290&view=rev
Log:
Add a bit to mark operands of asm's that conflict
with an earlyclobber operand elsewhere.  Propagate
this bit and the earlyclobber bit through SDISel.
Change linear-scan RA not to allocate regs in a way 
that conflicts with an earlyclobber.  See also comments.


Added:
    llvm/trunk/test/CodeGen/X86/2008-09-17-inline-asm-1.ll
Modified:
    llvm/trunk/include/llvm/CodeGen/LiveIntervalAnalysis.h
    llvm/trunk/include/llvm/CodeGen/MachineOperand.h
    llvm/trunk/include/llvm/CodeGen/ScheduleDAG.h
    llvm/trunk/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
    llvm/trunk/lib/CodeGen/LiveIntervalAnalysis.cpp
    llvm/trunk/lib/CodeGen/MachineInstr.cpp
    llvm/trunk/lib/CodeGen/RegAllocLinearScan.cpp
    llvm/trunk/lib/CodeGen/SelectionDAG/ScheduleDAGEmit.cpp
    llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp
    llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp

Modified: llvm/trunk/include/llvm/CodeGen/LiveIntervalAnalysis.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/CodeGen/LiveIntervalAnalysis.h?rev=56290&r1=56289&r2=56290&view=diff

==============================================================================
--- llvm/trunk/include/llvm/CodeGen/LiveIntervalAnalysis.h (original)
+++ llvm/trunk/include/llvm/CodeGen/LiveIntervalAnalysis.h Wed Sep 17 16:13:11 2008
@@ -28,6 +28,7 @@
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/Support/Allocator.h"
 #include <cmath>
+#include <map>
 
 namespace llvm {
 
@@ -64,6 +65,22 @@
     AliasAnalysis *aa_;
     LiveVariables* lv_;
 
+    /// AsmsWithEarlyClobber - maps a virtual register number to all the
+    /// inline asm's that have the register marked earlyclobber.
+    /// 
+    std::multimap<unsigned, MachineInstr*> AsmsThatEarlyClobber;
+
+    /// AsmsWithEarlyClobberConflict - maps a virtual register number
+    /// to all the inline asm's that have earlyclobber operands elsewhere
+    /// and use the register as a (non-earlyclobber) input.
+    ///
+    /// Note: earlyclobber operands may not be assigned the same register as
+    /// each other, or as earlyclobber-conflict operands.  However two
+    /// earlyclobber-conflict operands may be assigned the same register if
+    /// they happen to contain the same value.
+    /// 
+    std::multimap<unsigned, MachineInstr*> AsmsWithEarlyClobberConflict;
+
     /// Special pool allocator for VNInfo's (LiveInterval val#).
     ///
     BumpPtrAllocator VNInfoAllocator;
@@ -336,6 +353,11 @@
     unsigned getNumConflictsWithPhysReg(const LiveInterval &li,
                                         unsigned PhysReg) const;
 
+    /// noEarlyclobberConflict - see whether virtual reg VReg has a conflict
+    /// with hard reg HReg because HReg is used as an earlyclobber register in
+    /// asm that also has VReg live into or across it.
+    bool noEarlyclobberConflict(unsigned VReg, VirtRegMap &vrm, unsigned HReg);
+
     /// computeNumbering - Compute the index numbering.
     void computeNumbering();
 

Modified: llvm/trunk/include/llvm/CodeGen/MachineOperand.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/CodeGen/MachineOperand.h?rev=56290&r1=56289&r2=56290&view=diff

==============================================================================
--- llvm/trunk/include/llvm/CodeGen/MachineOperand.h (original)
+++ llvm/trunk/include/llvm/CodeGen/MachineOperand.h Wed Sep 17 16:13:11 2008
@@ -73,6 +73,12 @@
   /// for description of earlyclobber.
   bool IsEarlyClobber : 1;
 
+  /// OverlapsEarlyClobber - True if this MO_Register operand is used as an
+  /// input to an inline asm that has the earlyclobber bit set on some other
+  /// operand.  Flag is not valid for any other case.   See gcc doc
+  /// for description of earlyclobber.
+  bool OverlapsEarlyClobber : 1;
+
   /// SubReg - Subregister number, only valid for MO_Register.  A value of 0
   /// indicates the MO_Register has no subReg.
   unsigned char SubReg;
@@ -182,6 +188,11 @@
     return IsEarlyClobber;
   }
 
+  bool overlapsEarlyClobber() const {
+    assert(isRegister() && "Wrong MachineOperand accessor");
+    return OverlapsEarlyClobber;
+  }
+
   /// getNextOperandForReg - Return the next MachineOperand in the function that
   /// uses or defines this register.
   MachineOperand *getNextOperandForReg() const {
@@ -232,6 +243,11 @@
     IsEarlyClobber = Val;
   }
 
+  void setOverlapsEarlyClobber(bool Val = true) {
+    assert(isRegister() && "Wrong MachineOperand accessor");
+    OverlapsEarlyClobber = Val;
+  }
+
   //===--------------------------------------------------------------------===//
   // Accessors for various operand types.
   //===--------------------------------------------------------------------===//
@@ -337,13 +353,15 @@
   static MachineOperand CreateReg(unsigned Reg, bool isDef, bool isImp = false,
                                   bool isKill = false, bool isDead = false,
                                   unsigned SubReg = 0,
-                                  bool isEarlyClobber = false) {
+                                  bool isEarlyClobber = false,
+                                  bool overlapsEarlyClobber = false) {
     MachineOperand Op(MachineOperand::MO_Register);
     Op.IsDef = isDef;
     Op.IsImp = isImp;
     Op.IsKill = isKill;
     Op.IsDead = isDead;
     Op.IsEarlyClobber = isEarlyClobber;
+    Op.OverlapsEarlyClobber = overlapsEarlyClobber;
     Op.Contents.Reg.RegNo = Reg;
     Op.Contents.Reg.Prev = 0;
     Op.Contents.Reg.Next = 0;
@@ -390,6 +408,7 @@
     IsKill   = MO.IsKill;
     IsDead   = MO.IsDead;
     IsEarlyClobber = MO.IsEarlyClobber;
+    OverlapsEarlyClobber = MO.OverlapsEarlyClobber;
     SubReg   = MO.SubReg;
     ParentMI = MO.ParentMI;
     Contents = MO.Contents;

Modified: llvm/trunk/include/llvm/CodeGen/ScheduleDAG.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/CodeGen/ScheduleDAG.h?rev=56290&r1=56289&r2=56290&view=diff

==============================================================================
--- llvm/trunk/include/llvm/CodeGen/ScheduleDAG.h (original)
+++ llvm/trunk/include/llvm/CodeGen/ScheduleDAG.h Wed Sep 17 16:13:11 2008
@@ -361,7 +361,8 @@
 
     void AddOperand(MachineInstr *MI, SDValue Op, unsigned IIOpNum,
                     const TargetInstrDesc *II,
-                    DenseMap<SDValue, unsigned> &VRBaseMap);
+                    DenseMap<SDValue, unsigned> &VRBaseMap,
+                    bool overlapsEarlyClobber = false);
 
     void AddMemOperand(MachineInstr *MI, const MachineMemOperand &MO);
 

Modified: llvm/trunk/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/AsmPrinter/AsmPrinter.cpp?rev=56290&r1=56289&r2=56290&view=diff

==============================================================================
--- llvm/trunk/lib/CodeGen/AsmPrinter/AsmPrinter.cpp (original)
+++ llvm/trunk/lib/CodeGen/AsmPrinter/AsmPrinter.cpp Wed Sep 17 16:13:11 2008
@@ -1325,7 +1325,8 @@
                                  false, false, false);
           else {
             AsmPrinter *AP = const_cast<AsmPrinter*>(this);
-            if ((OpFlags & 7) == 4 /*ADDR MODE*/) {
+            if ((OpFlags & 7) == 4 /*ADDR MODE*/ ||
+                (OpFlags & 7) == 7) /*ADDR MODE OVERLAPS EARLYCLOBBER*/ {
               Error = AP->PrintAsmMemoryOperand(MI, OpNo, AsmPrinterVariant,
                                                 Modifier[0] ? Modifier : 0);
             } else {

Modified: llvm/trunk/lib/CodeGen/LiveIntervalAnalysis.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/LiveIntervalAnalysis.cpp?rev=56290&r1=56289&r2=56290&view=diff

==============================================================================
--- llvm/trunk/lib/CodeGen/LiveIntervalAnalysis.cpp (original)
+++ llvm/trunk/lib/CodeGen/LiveIntervalAnalysis.cpp Wed Sep 17 16:13:11 2008
@@ -673,7 +673,10 @@
 /// registers. for some ordering of the machine instructions [1,N] a
 /// live interval is an interval [i, j) where 1 <= i <= j < N for
 /// which a variable is live
-void LiveIntervals::computeIntervals() {
+void LiveIntervals::computeIntervals() { 
+  AsmsThatEarlyClobber.clear();
+  AsmsWithEarlyClobberConflict.clear();
+
   DOUT << "********** COMPUTING LIVE INTERVALS **********\n"
        << "********** Function: "
        << ((Value*)mf_->getFunction())->getName() << '\n';
@@ -710,8 +713,17 @@
       for (int i = MI->getNumOperands() - 1; i >= 0; --i) {
         MachineOperand &MO = MI->getOperand(i);
         // handle register defs - build intervals
-        if (MO.isRegister() && MO.getReg() && MO.isDef())
+        if (MO.isRegister() && MO.getReg() && MO.isDef()) {
           handleRegisterDef(MBB, MI, MIIndex, MO, i);
+          if (MO.isEarlyClobber()) {
+            AsmsThatEarlyClobber.insert(std::make_pair(MO.getReg(), MI));
+          }
+        }
+        if (MO.isRegister() && !MO.isDef() &&
+            MO.getReg() && TargetRegisterInfo::isVirtualRegister(MO.getReg()) &&
+            MO.overlapsEarlyClobber()) {
+          AsmsWithEarlyClobberConflict.insert(std::make_pair(MO.getReg(), MI));
+        }
       }
       
       MIIndex += InstrSlots::NUM;
@@ -740,6 +752,72 @@
   return ResVal;
 }
 
+/// noEarlyclobberConflict - see whether virtual reg VReg has a conflict with
+/// hard reg HReg because of earlyclobbers.  
+///
+/// Earlyclobber operands may not be assigned the same register as
+/// each other, or as earlyclobber-conflict operands (i.e. those that
+/// are non-earlyclobbered inputs to an asm that also has earlyclobbers).
+///
+/// Thus there are two cases to check for:
+/// 1.  VReg is an earlyclobber-conflict register and HReg is an earlyclobber
+/// register in some asm that also has VReg as an input.
+/// 2.  VReg is an earlyclobber register and HReg is an earlyclobber-conflict
+/// input elsewhere in some asm.
+/// In both cases HReg can be assigned by the user, or assigned early in
+/// register allocation.
+/// 
+/// Dropping the distinction between earlyclobber and earlyclobber-conflict,
+/// keeping only one multimap, looks promising, but two earlyclobber-conflict
+/// operands may be assigned the same register if they happen to contain the 
+/// same value, and that implementation would prevent this.
+///
+bool LiveIntervals::noEarlyclobberConflict(unsigned VReg, VirtRegMap &vrm,
+                                           unsigned HReg) {
+  typedef std::multimap<unsigned, MachineInstr*>::iterator It;
+
+  // Short circuit the most common case.
+  if (AsmsWithEarlyClobberConflict.size()!=0) {
+    std::pair<It, It> x = AsmsWithEarlyClobberConflict.equal_range(VReg);
+    for (It I = x.first; I!=x.second; I++) {
+      MachineInstr* MI = I->second;
+      for (int i = MI->getNumOperands() - 1; i >= 0; --i) {
+        MachineOperand &MO = MI->getOperand(i);
+        if (MO.isRegister() && MO.isEarlyClobber()) {
+          unsigned PhysReg = MO.getReg();
+          if (PhysReg && TargetRegisterInfo::isVirtualRegister(PhysReg)) {
+            if (!vrm.hasPhys(PhysReg))
+              continue;
+            PhysReg = vrm.getPhys(PhysReg);
+          }
+          if (PhysReg==HReg)
+            return false;
+        }
+      }
+    }
+  }
+  // Short circuit the most common case.
+  if (AsmsThatEarlyClobber.size()!=0) {
+    std::pair<It, It> x = AsmsThatEarlyClobber.equal_range(VReg);
+    for (It I = x.first; I!=x.second; I++) {
+      MachineInstr* MI = I->second;
+      for (int i = MI->getNumOperands() - 1; i >= 0; --i) {
+        MachineOperand &MO = MI->getOperand(i);
+        if (MO.isRegister() && MO.overlapsEarlyClobber()) {
+          unsigned PhysReg = MO.getReg();
+          if (PhysReg && TargetRegisterInfo::isVirtualRegister(PhysReg)) {
+            if (!vrm.hasPhys(PhysReg))
+              continue;
+            PhysReg = vrm.getPhys(PhysReg);
+          }
+          if (PhysReg==HReg)
+            return false;
+        }
+      }
+    }
+  }
+  return true;
+}
 
 LiveInterval* LiveIntervals::createInterval(unsigned reg) {
   float Weight = TargetRegisterInfo::isPhysicalRegister(reg) ?

Modified: llvm/trunk/lib/CodeGen/MachineInstr.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/MachineInstr.cpp?rev=56290&r1=56289&r2=56290&view=diff

==============================================================================
--- llvm/trunk/lib/CodeGen/MachineInstr.cpp (original)
+++ llvm/trunk/lib/CodeGen/MachineInstr.cpp Wed Sep 17 16:13:11 2008
@@ -109,6 +109,7 @@
   // register's use/def lists.
   if (isRegister()) {
     assert(!isEarlyClobber());
+    assert(!isEarlyClobber() && !overlapsEarlyClobber());
     setReg(Reg);
   } else {
     // Otherwise, change this to a register and set the reg#.
@@ -128,6 +129,7 @@
   IsKill = isKill;
   IsDead = isDead;
   IsEarlyClobber = false;
+  OverlapsEarlyClobber = false;
   SubReg = 0;
 }
 
@@ -183,13 +185,20 @@
         OS << "%mreg" << getReg();
     }
       
-    if (isDef() || isKill() || isDead() || isImplicit() || isEarlyClobber()) {
+    if (isDef() || isKill() || isDead() || isImplicit() || isEarlyClobber() ||
+        overlapsEarlyClobber()) {
       OS << "<";
       bool NeedComma = false;
+      if (overlapsEarlyClobber()) {
+        NeedComma = true;
+        OS << "overlapsearly";
+      }
       if (isImplicit()) {
+        if (NeedComma) OS << ",";
         OS << (isDef() ? "imp-def" : "imp-use");
         NeedComma = true;
       } else if (isDef()) {
+        if (NeedComma) OS << ",";
         if (isEarlyClobber())
           OS << "earlyclobber,";
         OS << "def";

Modified: llvm/trunk/lib/CodeGen/RegAllocLinearScan.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/RegAllocLinearScan.cpp?rev=56290&r1=56289&r2=56290&view=diff

==============================================================================
--- llvm/trunk/lib/CodeGen/RegAllocLinearScan.cpp (original)
+++ llvm/trunk/lib/CodeGen/RegAllocLinearScan.cpp Wed Sep 17 16:13:11 2008
@@ -1050,7 +1050,8 @@
   TargetRegisterClass::iterator E = RC->allocation_order_end(*mf_);
   assert(I != E && "No allocatable register in this register class!");
   for (; I != E; ++I)
-    if (prt_->isRegAvail(*I)) {
+    if (prt_->isRegAvail(*I) && 
+        li_->noEarlyclobberConflict(cur->reg, *vrm_, *I)) {
       FreeReg = *I;
       if (FreeReg < inactiveCounts.size())
         FreeRegInactiveCount = inactiveCounts[FreeReg];
@@ -1070,7 +1071,8 @@
   for (; I != E; ++I) {
     unsigned Reg = *I;
     if (prt_->isRegAvail(Reg) && Reg < inactiveCounts.size() &&
-        FreeRegInactiveCount < inactiveCounts[Reg]) {
+        FreeRegInactiveCount < inactiveCounts[Reg] &&
+        li_->noEarlyclobberConflict(cur->reg, *vrm_, Reg)) {
       FreeReg = Reg;
       FreeRegInactiveCount = inactiveCounts[Reg];
       if (FreeRegInactiveCount == MaxInactiveCount)

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/ScheduleDAGEmit.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/ScheduleDAGEmit.cpp?rev=56290&r1=56289&r2=56290&view=diff

==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/ScheduleDAGEmit.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/ScheduleDAGEmit.cpp Wed Sep 17 16:13:11 2008
@@ -231,7 +231,8 @@
 void ScheduleDAG::AddOperand(MachineInstr *MI, SDValue Op,
                              unsigned IIOpNum,
                              const TargetInstrDesc *II,
-                             DenseMap<SDValue, unsigned> &VRBaseMap) {
+                             DenseMap<SDValue, unsigned> &VRBaseMap,
+                             bool overlapsEarlyClobber) {
   if (Op.isMachineOpcode()) {
     // Note that this case is redundant with the final else block, but we
     // include it because it is the most common and it makes the logic
@@ -244,7 +245,9 @@
     const TargetInstrDesc &TID = MI->getDesc();
     bool isOptDef = IIOpNum < TID.getNumOperands() &&
       TID.OpInfo[IIOpNum].isOptionalDef();
-    MI->addOperand(MachineOperand::CreateReg(VReg, isOptDef));
+    MI->addOperand(MachineOperand::CreateReg(VReg, isOptDef, false, false,
+                                             false, 0, false,
+                                             overlapsEarlyClobber));
     
     // Verify that it is right.
     assert(TargetRegisterInfo::isVirtualRegister(VReg) && "Not a vreg?");
@@ -278,7 +281,9 @@
     const ConstantFP *CFP = F->getConstantFPValue();
     MI->addOperand(MachineOperand::CreateFPImm(CFP));
   } else if (RegisterSDNode *R = dyn_cast<RegisterSDNode>(Op)) {
-    MI->addOperand(MachineOperand::CreateReg(R->getReg(), false));
+    MI->addOperand(MachineOperand::CreateReg(R->getReg(), false, false,
+                                             false, false, 0, false,
+                                             overlapsEarlyClobber));
   } else if (GlobalAddressSDNode *TGA = dyn_cast<GlobalAddressSDNode>(Op)) {
     MI->addOperand(MachineOperand::CreateGA(TGA->getGlobal(),TGA->getOffset()));
   } else if (BasicBlockSDNode *BB = dyn_cast<BasicBlockSDNode>(Op)) {
@@ -314,7 +319,9 @@
            Op.getValueType() != MVT::Flag &&
            "Chain and flag operands should occur at end of operand list!");
     unsigned VReg = getVR(Op, VRBaseMap);
-    MI->addOperand(MachineOperand::CreateReg(VReg, false));
+    MI->addOperand(MachineOperand::CreateReg(VReg, false, false,
+                                             false, false, 0, false,
+                                             overlapsEarlyClobber));
     
     // Verify that it is right.  Note that the reg class of the physreg and the
     // vreg don't necessarily need to match, but the target copy insertion has
@@ -596,6 +603,7 @@
       
     // Add all of the operand registers to the instruction.
     for (unsigned i = 2; i != NumOps;) {
+      bool overlapsEarlyClobber = false;
       unsigned Flags =
         cast<ConstantSDNode>(Node->getOperand(i))->getZExtValue();
       unsigned NumVals = Flags >> 3;
@@ -618,13 +626,18 @@
                                                    false, 0, true));
         }
         break;
+      case 7:  // Addressing mode overlapping earlyclobber.
+      case 5:  // Use of register overlapping earlyclobber.
+        overlapsEarlyClobber = true;
+        // fall through
       case 1:  // Use of register.
       case 3:  // Immediate.
       case 4:  // Addressing mode.
         // The addressing mode has been selected, just add all of the
         // operands to the machine instruction.
         for (; NumVals; --NumVals, ++i)
-          AddOperand(MI, Node->getOperand(i), 0, 0, VRBaseMap);
+          AddOperand(MI, Node->getOperand(i), 0, 0, VRBaseMap, 
+                     overlapsEarlyClobber);
         break;
       }
     }

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp?rev=56290&r1=56289&r2=56290&view=diff

==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp Wed Sep 17 16:13:11 2008
@@ -4909,8 +4909,10 @@
         assert(OpInfo.isIndirect && "Memory output must be indirect operand");
 
         // Add information to the INLINEASM node to know about this output.
-        unsigned ResOpType = 4/*MEM*/ | (1 << 3);
-        AsmNodeOperands.push_back(DAG.getTargetConstant(ResOpType, 
+        unsigned ResOpType = SawEarlyClobber ? 
+                                  7 /* MEM OVERLAPS EARLYCLOBBER */ :
+                                  4/*MEM*/;
+        AsmNodeOperands.push_back(DAG.getTargetConstant(ResOpType | (1<<3), 
                                                         TLI.getPointerTy()));
         AsmNodeOperands.push_back(OpInfo.CallOperand);
         break;
@@ -4963,7 +4965,8 @@
             cast<ConstantSDNode>(AsmNodeOperands[CurOp])->getZExtValue();
           assert(((NumOps & 7) == 2 /*REGDEF*/ ||
                   (NumOps & 7) == 6 /*EARLYCLOBBER REGDEF*/ ||
-                  (NumOps & 7) == 4 /*MEM*/) &&
+                  (NumOps & 7) == 4 /*MEM*/ ||
+                  (NumOps & 7) == 7 /*MEM OVERLAPS EARLYCLOBBER*/) &&
                  "Skipped past definitions?");
           CurOp += (NumOps>>3)+1;
         }
@@ -4985,14 +4988,17 @@
         
           // Use the produced MatchedRegs object to 
           MatchedRegs.getCopyToRegs(InOperandVal, DAG, Chain, &Flag);
-          MatchedRegs.AddInlineAsmOperands(1 /*REGUSE*/, DAG, AsmNodeOperands);
+          MatchedRegs.AddInlineAsmOperands(SawEarlyClobber ? 
+                                           1 /*REGUSE*/ :
+                                           5 /*REGUSE OVERLAPS EARLYCLOBBER*/, 
+                                           DAG, AsmNodeOperands);
           break;
         } else {
-          assert((NumOps & 7) == 4/*MEM*/ && "Unknown matching constraint!");
+          assert(((NumOps & 7) == 7/*MEM OVERLAPS EARLYCLOBBER */ ||
+                  (NumOps & 7) == 4) && "Unknown matching constraint!");
           assert((NumOps >> 3) == 1 && "Unexpected number of operands"); 
           // Add information to the INLINEASM node to know about this input.
-          unsigned ResOpType = 4/*MEM*/ | (1 << 3);
-          AsmNodeOperands.push_back(DAG.getTargetConstant(ResOpType,
+          AsmNodeOperands.push_back(DAG.getTargetConstant(NumOps,
                                                           TLI.getPointerTy()));
           AsmNodeOperands.push_back(AsmNodeOperands[CurOp+1]);
           break;
@@ -5024,8 +5030,10 @@
                "Memory operands expect pointer values");
                
         // Add information to the INLINEASM node to know about this input.
-        unsigned ResOpType = 4/*MEM*/ | (1 << 3);
-        AsmNodeOperands.push_back(DAG.getTargetConstant(ResOpType,
+        unsigned ResOpType = SawEarlyClobber ? 
+                                7 /* MEM OVERLAPS EARLYCLOBBER */ : 
+                                4/*MEM*/;
+        AsmNodeOperands.push_back(DAG.getTargetConstant(ResOpType | (1<<3),
                                                         TLI.getPointerTy()));
         AsmNodeOperands.push_back(InOperandVal);
         break;
@@ -5043,16 +5051,18 @@
 
       OpInfo.AssignedRegs.getCopyToRegs(InOperandVal, DAG, Chain, &Flag);
       
-      OpInfo.AssignedRegs.AddInlineAsmOperands(1/*REGUSE*/, DAG,
-                                               AsmNodeOperands);
+      OpInfo.AssignedRegs.AddInlineAsmOperands(SawEarlyClobber ?
+                                           5 /*REGUSE OVERLAPS EARLYCLOBBER*/:
+                                           1/*REGUSE*/,
+                                           DAG, AsmNodeOperands);
       break;
     }
     case InlineAsm::isClobber: {
       // Add the clobbered value to the operand list, so that the register
       // allocator is aware that the physreg got clobbered.
       if (!OpInfo.AssignedRegs.Regs.empty())
-        OpInfo.AssignedRegs.AddInlineAsmOperands(2/*REGDEF*/, DAG,
-                                                 AsmNodeOperands);
+        OpInfo.AssignedRegs.AddInlineAsmOperands(6 /* EARLYCLOBBER REGDEF */,
+                                                 DAG, AsmNodeOperands);
       break;
     }
     }

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp?rev=56290&r1=56289&r2=56290&view=diff

==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp Wed Sep 17 16:13:11 2008
@@ -1113,7 +1113,8 @@
   
   while (i != e) {
     unsigned Flags = cast<ConstantSDNode>(InOps[i])->getZExtValue();
-    if ((Flags & 7) != 4 /*MEM*/) {
+    if ((Flags & 7) != 4 /*MEM*/ &&
+        (Flags & 7) != 7 /*MEM OVERLAPS EARLYCLOBBER*/) {
       // Just skip over this operand, copying the operands verbatim.
       Ops.insert(Ops.end(), InOps.begin()+i, InOps.begin()+i+(Flags >> 3) + 1);
       i += (Flags >> 3) + 1;
@@ -1128,7 +1129,7 @@
       
       // Add this to the output node.
       MVT IntPtrTy = CurDAG->getTargetLoweringInfo().getPointerTy();
-      Ops.push_back(CurDAG->getTargetConstant(4/*MEM*/ | (SelOps.size() << 3),
+      Ops.push_back(CurDAG->getTargetConstant((Flags & 7) | (SelOps.size()<< 3),
                                               IntPtrTy));
       Ops.insert(Ops.end(), SelOps.begin(), SelOps.end());
       i += 2;

Added: llvm/trunk/test/CodeGen/X86/2008-09-17-inline-asm-1.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/2008-09-17-inline-asm-1.ll?rev=56290&view=auto

==============================================================================
--- llvm/trunk/test/CodeGen/X86/2008-09-17-inline-asm-1.ll (added)
+++ llvm/trunk/test/CodeGen/X86/2008-09-17-inline-asm-1.ll Wed Sep 17 16:13:11 2008
@@ -0,0 +1,24 @@
+; RUN: llvm-as < %s | llc -o - -march=x86 | not grep "movl %eax, %eax"
+; RUN: llvm-as < %s | llc -o - -march=x86 | not grep "movl %edx, %edx"
+; RUN: llvm-as < %s | llc -o - -march=x86 | not grep "movl (%eax), %eax"
+; RUN: llvm-as < %s | llc -o - -march=x86 | not grep "movl (%edx), %edx"
+
+; %0 must not be put in EAX or EDX.
+; In the first asm, $0 and $2 must not be put in EAX.
+; In the second asm, $0 and $2 must not be put in EDX.
+; This is kind of hard to test thoroughly, but the things above should continue
+; to pass, I think.
+; ModuleID = '<stdin>'
+target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128"
+target triple = "i386-apple-darwin8"
+ at x = common global i32 0		; <i32*> [#uses=1]
+
+define i32 @aci(i32* %pw) nounwind {
+entry:
+	%0 = load i32* @x, align 4		; <i32> [#uses=1]
+	%asmtmp = tail call { i32, i32 } asm "movl $0, %eax\0A\090:\0A\09test %eax, %eax\0A\09je 1f\0A\09movl %eax, $2\0A\09incl $2\0A\09lock\0A\09cmpxchgl $2, $0\0A\09jne 0b\0A\091:", "=*m,=&{ax},=&r,*m,~{dirflag},~{fpsr},~{flags},~{memory},~{cc}"(i32* %pw, i32* %pw) nounwind		; <{ i32, i32 }> [#uses=0]
+	%asmtmp2 = tail call { i32, i32 } asm "movl $0, %edx\0A\090:\0A\09test %edx, %edx\0A\09je 1f\0A\09movl %edx, $2\0A\09incl $2\0A\09lock\0A\09cmpxchgl $2, $0\0A\09jne 0b\0A\091:", "=*m,=&{dx},=&r,*m,~{dirflag},~{fpsr},~{flags},~{memory},~{cc}"(i32* %pw, i32* %pw) nounwind		; <{ i32, i32 }> [#uses=1]
+	%asmresult3 = extractvalue { i32, i32 } %asmtmp2, 0		; <i32> [#uses=1]
+	%1 = add i32 %asmresult3, %0		; <i32> [#uses=1]
+	ret i32 %1
+}





More information about the llvm-commits mailing list