1 files changed, 73 insertions, 50 deletions
diff --git a/lib/Target/PIC16/PIC16ISelLowering.h b/lib/Target/PIC16/PIC16ISelLowering.h
index e14a0c2..dfe5b5f 100644
--- a/lib/Target/PIC16/PIC16ISelLowering.h
+++ b/lib/Target/PIC16/PIC16ISelLowering.h
@@ -26,66 +26,89 @@ namespace llvm {
       // Start the numbering from where ISD NodeType finishes.
       FIRST_NUMBER = ISD::BUILTIN_OP_END,
 
-      // used for encapsulating the expanded nodes into one node.
-      Package,
-
-      // Get the Higher 16 bits from a 32-bit immediate
-      Hi, 
-
-      // Get the Lower 16 bits from a 32-bit immediate
-      Lo,
-
-      Cmp,        // PIC16 Generic Comparison instruction.
-      Branch,        // PIC16 Generic Branch Instruction.        
-      BTFSS,        // PIC16 BitTest Instruction (Skip if set).
-      BTFSC,        // PIC16 BitTest Instruction (Skip if clear).
-
-      // PIC16 comparison to be converted to either XOR or SUB
-      // Following instructions cater to those convertions.
-      XORCC,        
-      SUBCC,        
-
-      // Get the Global Address wrapped into a wrapper that also captures 
-      // the bank or page.
-      Wrapper,
-      SetBank,
-      SetPage
+      Lo,            // Low 8-bits of GlobalAddress.
+      Hi,            // High 8-bits of GlobalAddress.
+      PIC16Load,
+      PIC16Store,
+      Banksel,
+      MTLO,
+      MTHI,
+      BCF,
+      LSLF,          // PIC16 Logical shift left
+      LRLF,          // PIC16 Logical shift right
+      RLF,           // Rotate left through carry
+      RRF,           // Rotate right through carry
+      Dummy
+    };
+
+    // Keep track of different address spaces. 
+    enum AddressSpace {
+      RAM_SPACE = 0,   // RAM address space
+      ROM_SPACE = 1    // ROM address space number is 1
     };
   }
 
   //===--------------------------------------------------------------------===//
   // TargetLowering Implementation
   //===--------------------------------------------------------------------===//
-  class PIC16TargetLowering : public TargetLowering 
-  {
+  class PIC16TargetLowering : public TargetLowering {
   public:
-    typedef std::map<SDNode *, SDNode *> NodeMap_t;
-
     explicit PIC16TargetLowering(PIC16TargetMachine &TM);
 
-    /// LowerOperation - Provide custom lowering hooks for some operations.
-    virtual SDValue LowerOperation(SDValue Op, SelectionDAG &DAG);
-
-    SDValue LowerGlobalAddress(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerFORMAL_ARGUMENTS(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerRET(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerFrameIndex(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerBR_CC(SDValue Op, SelectionDAG &DAG);
-
-    SDValue RemoveHiLo(SDNode *, SelectionDAG &DAG, 
-                         DAGCombinerInfo &DCI) const;
-    SDValue LowerADDSUB(SDNode *, SelectionDAG &DAG, 
-                          DAGCombinerInfo &DCI) const;
-    SDValue LowerLOAD(SDNode *, SelectionDAG &DAG, 
-                        DAGCombinerInfo &DCI) const;
-
-    /// getTargetNodeName - This method returns the name of a target specific 
-    //  DAG node.
+    /// getTargetNodeName - This method returns the name of a target specific
+    /// DAG node.
     virtual const char *getTargetNodeName(unsigned Opcode) const;
-    virtual SDValue PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI) const;
-
-    // utility function.
-    const SDValue *findLoadi8(const SDValue &Src, SelectionDAG &DAG) const;
+    SDValue LowerOperation(SDValue Op, SelectionDAG &DAG);
+    SDValue LowerFORMAL_ARGUMENTS(SDValue Op, SelectionDAG &DAG);
+    SDValue LowerADDE(SDValue Op, SelectionDAG &DAG);
+    SDValue LowerADDC(SDValue Op, SelectionDAG &DAG);
+    SDValue LowerSUBE(SDValue Op, SelectionDAG &DAG);
+    SDValue LowerSUBC(SDValue Op, SelectionDAG &DAG);
+
+    SDNode *ReplaceNodeResults(SDNode *N, SelectionDAG &DAG);
+    SDNode *ExpandStore(SDNode *N, SelectionDAG &DAG);
+    SDNode *ExpandLoad(SDNode *N, SelectionDAG &DAG);
+    SDNode *ExpandAdd(SDNode *N, SelectionDAG &DAG);
+    SDNode *ExpandGlobalAddress(SDNode *N, SelectionDAG &DAG);
+    SDNode *ExpandShift(SDNode *N, SelectionDAG &DAG);
+
+    SDValue PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI) const; 
+    SDValue PerformPIC16LoadCombine(SDNode *N, DAGCombinerInfo &DCI) const; 
+
+  private:
+    // If the Node is a BUILD_PAIR representing representing an Address
+    // then this function will return true
+    bool isDirectAddress(const SDValue &Op);
+
+    // If the Node is a DirectAddress in ROM_SPACE then this 
+    // function will return true
+    bool isRomAddress(const SDValue &Op);
+
+    // To extract chain value from the SDValue Nodes
+    // This function will help to maintain the chain extracting
+    // code at one place. In case of any change in future it will
+    // help maintain the code
+    SDValue getChain(SDValue &Op);
+
+
+    // Extract the Lo and Hi component of Op. 
+    void GetExpandedParts(SDValue Op, SelectionDAG &DAG, SDValue &Lo, 
+                          SDValue &Hi); 
+
+
+    // Load pointer can be a direct or indirect address. In PIC16 direct
+    // addresses need Banksel and Indirect addresses need to be loaded to
+    // FSR first. Handle address specific cases here.
+    void LegalizeAddress(SDValue Ptr, SelectionDAG &DAG, SDValue &Chain, 
+                         SDValue &NewPtr, unsigned &Offset);
+
+    // We can not have both operands of a binary operation in W.
+    // This function is used to put one operand on stack and generate a load.
+    SDValue ConvertToMemOperand(SDValue Op, SelectionDAG &DAG); 
+
+    /// Subtarget - Keep a pointer to the PIC16Subtarget around so that we can
+    /// make the right decision when generating code for different targets.
+    const PIC16Subtarget *Subtarget;
   };
 } // namespace llvm