[SystemZ] Use MVST to implement strcpy and stpcpy

llvm-svn: 188546

8 files changed, 68 insertions, 0 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index b1812f2cda9..9bb78978e11 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -5558,6 +5558,35 @@ bool SelectionDAGBuilder::visitMemCmpCall(const CallInst &I) {
   return false;
 }
 
+/// visitStrCpyCall -- See if we can lower a strcpy or stpcpy call into an
+/// optimized form.  If so, return true and lower it, otherwise return false
+/// and it will be lowered like a normal call.
+bool SelectionDAGBuilder::visitStrCpyCall(const CallInst &I, bool isStpcpy) {
+  // Verify that the prototype makes sense.  char *strcpy(char *, char *)
+  if (I.getNumArgOperands() != 2)
+    return false;
+
+  const Value *Arg0 = I.getArgOperand(0), *Arg1 = I.getArgOperand(1);
+  if (!Arg0->getType()->isPointerTy() ||
+      !Arg1->getType()->isPointerTy() ||
+      !I.getType()->isPointerTy())
+    return false;
+
+  const TargetSelectionDAGInfo &TSI = DAG.getSelectionDAGInfo();
+  std::pair<SDValue, SDValue> Res =
+    TSI.EmitTargetCodeForStrcpy(DAG, getCurSDLoc(), getRoot(),
+                                getValue(Arg0), getValue(Arg1),
+                                MachinePointerInfo(Arg0),
+                                MachinePointerInfo(Arg1), isStpcpy);
+  if (Res.first.getNode()) {
+    setValue(&I, Res.first);
+    DAG.setRoot(Res.second);
+    return true;
+  }
+
+  return false;
+}
+
 /// visitStrCmpCall - See if we can lower a call to strcmp in an optimized form.
 /// If so, return true and lower it, otherwise return false and it will be
 /// lowered like a normal call.
@@ -5733,6 +5762,14 @@ void SelectionDAGBuilder::visitCall(const CallInst &I) {
         if (visitMemCmpCall(I))
           return;
         break;
+      case LibFunc::strcpy:
+        if (visitStrCpyCall(I, false))
+          return;
+        break;
+      case LibFunc::stpcpy:
+        if (visitStrCpyCall(I, true))
+          return;
+        break;
       case LibFunc::strcmp:
         if (visitStrCmpCall(I))
           return;
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.h b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.h
index ff15347aae5..7c6e671b73f 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.h
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.h
@@ -523,6 +523,7 @@ private:
   void visitPHI(const PHINode &I);
   void visitCall(const CallInst &I);
   bool visitMemCmpCall(const CallInst &I);
+  bool visitStrCpyCall(const CallInst &I, bool isStpcpy);
   bool visitStrCmpCall(const CallInst &I);
   bool visitUnaryFloatCall(const CallInst &I, unsigned Opcode);
   void visitAtomicLoad(const LoadInst &I);
diff --git a/llvm/lib/Target/SystemZ/SystemZISelLowering.cpp b/llvm/lib/Target/SystemZ/SystemZISelLowering.cpp
index 1fe54f1280f..b22cc40155d 100644
--- a/llvm/lib/Target/SystemZ/SystemZISelLowering.cpp
+++ b/llvm/lib/Target/SystemZ/SystemZISelLowering.cpp
@@ -1703,6 +1703,7 @@ const char *SystemZTargetLowering::getTargetNodeName(unsigned Opcode) const {
     OPCODE(MVC);
     OPCODE(CLC);
     OPCODE(STRCMP);
+    OPCODE(STPCPY);
     OPCODE(IPM);
     OPCODE(ATOMIC_SWAPW);
     OPCODE(ATOMIC_LOADW_ADD);
@@ -2551,6 +2552,8 @@ EmitInstrWithCustomInserter(MachineInstr *MI, MachineBasicBlock *MBB) const {
     return emitMemMemWrapper(MI, MBB, SystemZ::CLC);
   case SystemZ::CLSTLoop:
     return emitStringWrapper(MI, MBB, SystemZ::CLST);
+  case SystemZ::MVSTLoop:
+    return emitStringWrapper(MI, MBB, SystemZ::MVST);
   default:
     llvm_unreachable("Unexpected instr type to insert");
   }
diff --git a/llvm/lib/Target/SystemZ/SystemZISelLowering.h b/llvm/lib/Target/SystemZ/SystemZISelLowering.h
index 4ee87d3cb8e..b27f1672e83 100644
--- a/llvm/lib/Target/SystemZ/SystemZISelLowering.h
+++ b/llvm/lib/Target/SystemZ/SystemZISelLowering.h
@@ -84,6 +84,9 @@ namespace SystemZISD {
     // as for MVC.
     CLC,
 
+    // Use an MVST-based sequence to implement stpcpy().
+    STPCPY,
+
     // Use a CLST-based sequence to implement strcmp().  The two input operands
     // are the addresses of the strings to compare.
     STRCMP,
diff --git a/llvm/lib/Target/SystemZ/SystemZInstrInfo.td b/llvm/lib/Target/SystemZ/SystemZInstrInfo.td
index 31832f70d29..43537aa3cc1 100644
--- a/llvm/lib/Target/SystemZ/SystemZInstrInfo.td
+++ b/llvm/lib/Target/SystemZ/SystemZInstrInfo.td
@@ -336,6 +336,10 @@ def MVGHI : StoreSIL<"mvghi", 0xE548, store,         imm64sx16>;
 let mayLoad = 1, mayStore = 1 in
   defm MVC : MemorySS<"mvc", 0xD2, z_mvc>;
 
+// String moves.
+let mayLoad = 1, mayStore = 1, Defs = [CC], Uses = [R0W] in
+  defm MVST : StringRRE<"mvst", 0xB255, z_stpcpy>;
+
 defm LoadStore8_32  : MVCLoadStore<anyextloadi8, truncstorei8, i32,
                                    MVCWrapper, 1>;
 defm LoadStore16_32 : MVCLoadStore<anyextloadi16, truncstorei16, i32,
diff --git a/llvm/lib/Target/SystemZ/SystemZOperators.td b/llvm/lib/Target/SystemZ/SystemZOperators.td
index 816fb5d6b1c..e0eeab109d4 100644
--- a/llvm/lib/Target/SystemZ/SystemZOperators.td
+++ b/llvm/lib/Target/SystemZ/SystemZOperators.td
@@ -121,6 +121,8 @@ def z_clc               : SDNode<"SystemZISD::CLC", SDT_ZMemMemLength,
                                  [SDNPHasChain, SDNPOutGlue, SDNPMayLoad]>;
 def z_strcmp            : SDNode<"SystemZISD::STRCMP", SDT_ZString,
                                  [SDNPHasChain, SDNPOutGlue, SDNPMayLoad]>;
+def z_stpcpy            : SDNode<"SystemZISD::STPCPY", SDT_ZString,
+                                 [SDNPHasChain, SDNPMayStore, SDNPMayLoad]>;
 def z_ipm               : SDNode<"SystemZISD::IPM", SDT_ZI32Intrinsic,
                                  [SDNPInGlue]>;
 
diff --git a/llvm/lib/Target/SystemZ/SystemZSelectionDAGInfo.cpp b/llvm/lib/Target/SystemZ/SystemZSelectionDAGInfo.cpp
index 789594b36c6..0a2080db0b9 100644
--- a/llvm/lib/Target/SystemZ/SystemZSelectionDAGInfo.cpp
+++ b/llvm/lib/Target/SystemZ/SystemZSelectionDAGInfo.cpp
@@ -159,6 +159,17 @@ EmitTargetCodeForMemcmp(SelectionDAG &DAG, SDLoc DL, SDValue Chain,
 }
 
 std::pair<SDValue, SDValue> SystemZSelectionDAGInfo::
+EmitTargetCodeForStrcpy(SelectionDAG &DAG, SDLoc DL, SDValue Chain,
+                        SDValue Dest, SDValue Src,
+                        MachinePointerInfo DestPtrInfo,
+                        MachinePointerInfo SrcPtrInfo, bool isStpcpy) const {
+  SDVTList VTs = DAG.getVTList(Dest.getValueType(), MVT::Other);
+  SDValue EndDest = DAG.getNode(SystemZISD::STPCPY, DL, VTs, Chain, Dest, Src,
+                                DAG.getConstant(0, MVT::i32));
+  return std::make_pair(isStpcpy ? EndDest : Dest, EndDest.getValue(1));
+}
+
+std::pair<SDValue, SDValue> SystemZSelectionDAGInfo::
 EmitTargetCodeForStrcmp(SelectionDAG &DAG, SDLoc DL, SDValue Chain,
                         SDValue Src1, SDValue Src2,
                         MachinePointerInfo Op1PtrInfo,
diff --git a/llvm/lib/Target/SystemZ/SystemZSelectionDAGInfo.h b/llvm/lib/Target/SystemZ/SystemZSelectionDAGInfo.h
index c874a4d1925..123cb63c09c 100644
--- a/llvm/lib/Target/SystemZ/SystemZSelectionDAGInfo.h
+++ b/llvm/lib/Target/SystemZ/SystemZSelectionDAGInfo.h
@@ -47,6 +47,13 @@ public:
                           MachinePointerInfo Op2PtrInfo) const LLVM_OVERRIDE;
 
   virtual std::pair<SDValue, SDValue>
+  EmitTargetCodeForStrcpy(SelectionDAG &DAG, SDLoc DL, SDValue Chain,
+                          SDValue Dest, SDValue Src,
+                          MachinePointerInfo DestPtrInfo,
+                          MachinePointerInfo SrcPtrInfo,
+                          bool isStpcpy) const LLVM_OVERRIDE;
+
+  virtual std::pair<SDValue, SDValue>
   EmitTargetCodeForStrcmp(SelectionDAG &DAG, SDLoc DL, SDValue Chain,
                           SDValue Src1, SDValue Src2,
                           MachinePointerInfo Op1PtrInfo,