Use const qualifiers with TargetLowering. This eliminates several
const_casts, and it reinforces the design of the Target classes being
immutable.

SelectionDAGISel::IsLegalToFold is now a static member function, because
PIC16 uses it in an unconventional way. There is more room for API
cleanup here.

And PIC16's AsmPrinter no longer uses TargetLowering.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101635 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/PowerPC/PPCISelLowering.h b/lib/Target/PowerPC/PPCISelLowering.h
index dc934cf..8397a17 100644
--- a/lib/Target/PowerPC/PPCISelLowering.h
+++ b/lib/Target/PowerPC/PPCISelLowering.h
@@ -279,13 +279,13 @@
     
     /// LowerOperation - Provide custom lowering hooks for some operations.
     ///
-    virtual SDValue LowerOperation(SDValue Op, SelectionDAG &DAG);
+    virtual SDValue LowerOperation(SDValue Op, SelectionDAG &DAG) const;
 
     /// ReplaceNodeResults - Replace the results of node with an illegal result
     /// type with new values built out of custom code.
     ///
     virtual void ReplaceNodeResults(SDNode *N, SmallVectorImpl<SDValue>&Results,
-                                    SelectionDAG &DAG);
+                                    SelectionDAG &DAG) const;
 
     virtual SDValue PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI) const;
     
@@ -378,43 +378,43 @@
                                          SDValue &LROpOut,
                                          SDValue &FPOpOut,
                                          bool isDarwinABI,
-                                         DebugLoc dl);
+                                         DebugLoc dl) const;
 
-    SDValue LowerRETURNADDR(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerFRAMEADDR(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerConstantPool(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerBlockAddress(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerGlobalAddress(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerGlobalTLSAddress(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerJumpTable(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerSETCC(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerTRAMPOLINE(SDValue Op, SelectionDAG &DAG);
+    SDValue LowerRETURNADDR(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerFRAMEADDR(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerConstantPool(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerBlockAddress(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerGlobalAddress(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerGlobalTLSAddress(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerJumpTable(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerSETCC(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerTRAMPOLINE(SDValue Op, SelectionDAG &DAG) const;
     SDValue LowerVASTART(SDValue Op, SelectionDAG &DAG,
-                         const PPCSubtarget &Subtarget);
+                         const PPCSubtarget &Subtarget) const;
     SDValue LowerVAARG(SDValue Op, SelectionDAG &DAG,
-                       const PPCSubtarget &Subtarget);
+                       const PPCSubtarget &Subtarget) const;
     SDValue LowerSTACKRESTORE(SDValue Op, SelectionDAG &DAG,
-                                const PPCSubtarget &Subtarget);
+                                const PPCSubtarget &Subtarget) const;
     SDValue LowerDYNAMIC_STACKALLOC(SDValue Op, SelectionDAG &DAG,
-                                      const PPCSubtarget &Subtarget);
-    SDValue LowerSELECT_CC(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerFP_TO_INT(SDValue Op, SelectionDAG &DAG, DebugLoc dl);
-    SDValue LowerSINT_TO_FP(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerFLT_ROUNDS_(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerSHL_PARTS(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerSRL_PARTS(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerSRA_PARTS(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerBUILD_VECTOR(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerVECTOR_SHUFFLE(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerINTRINSIC_WO_CHAIN(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerSCALAR_TO_VECTOR(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerMUL(SDValue Op, SelectionDAG &DAG);
+                                      const PPCSubtarget &Subtarget) const;
+    SDValue LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerFP_TO_INT(SDValue Op, SelectionDAG &DAG, DebugLoc dl) const;
+    SDValue LowerSINT_TO_FP(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerFLT_ROUNDS_(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerSHL_PARTS(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerSRL_PARTS(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerSRA_PARTS(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerBUILD_VECTOR(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerVECTOR_SHUFFLE(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerINTRINSIC_WO_CHAIN(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerSCALAR_TO_VECTOR(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerMUL(SDValue Op, SelectionDAG &DAG) const;
 
     SDValue LowerCallResult(SDValue Chain, SDValue InFlag,
                             CallingConv::ID CallConv, bool isVarArg,
                             const SmallVectorImpl<ISD::InputArg> &Ins,
                             DebugLoc dl, SelectionDAG &DAG,
-                            SmallVectorImpl<SDValue> &InVals);
+                            SmallVectorImpl<SDValue> &InVals) const;
     SDValue FinishCall(CallingConv::ID CallConv, DebugLoc dl, bool isTailCall,
                        bool isVarArg,
                        SelectionDAG &DAG,
@@ -424,14 +424,14 @@
                        SDValue &Callee,
                        int SPDiff, unsigned NumBytes,
                        const SmallVectorImpl<ISD::InputArg> &Ins,
-                       SmallVectorImpl<SDValue> &InVals);
+                       SmallVectorImpl<SDValue> &InVals) const;
 
     virtual SDValue
       LowerFormalArguments(SDValue Chain,
                            CallingConv::ID CallConv, bool isVarArg,
                            const SmallVectorImpl<ISD::InputArg> &Ins,
                            DebugLoc dl, SelectionDAG &DAG,
-                           SmallVectorImpl<SDValue> &InVals);
+                           SmallVectorImpl<SDValue> &InVals) const;
 
     virtual SDValue
       LowerCall(SDValue Chain, SDValue Callee,
@@ -439,26 +439,26 @@
                 const SmallVectorImpl<ISD::OutputArg> &Outs,
                 const SmallVectorImpl<ISD::InputArg> &Ins,
                 DebugLoc dl, SelectionDAG &DAG,
-                SmallVectorImpl<SDValue> &InVals);
+                SmallVectorImpl<SDValue> &InVals) const;
 
     virtual SDValue
       LowerReturn(SDValue Chain,
                   CallingConv::ID CallConv, bool isVarArg,
                   const SmallVectorImpl<ISD::OutputArg> &Outs,
-                  DebugLoc dl, SelectionDAG &DAG);
+                  DebugLoc dl, SelectionDAG &DAG) const;
 
     SDValue
       LowerFormalArguments_Darwin(SDValue Chain,
                                   CallingConv::ID CallConv, bool isVarArg,
                                   const SmallVectorImpl<ISD::InputArg> &Ins,
                                   DebugLoc dl, SelectionDAG &DAG,
-                                  SmallVectorImpl<SDValue> &InVals);
+                                  SmallVectorImpl<SDValue> &InVals) const;
     SDValue
       LowerFormalArguments_SVR4(SDValue Chain,
                                 CallingConv::ID CallConv, bool isVarArg,
                                 const SmallVectorImpl<ISD::InputArg> &Ins,
                                 DebugLoc dl, SelectionDAG &DAG,
-                                SmallVectorImpl<SDValue> &InVals);
+                                SmallVectorImpl<SDValue> &InVals) const;
 
     SDValue
       LowerCall_Darwin(SDValue Chain, SDValue Callee,
@@ -466,14 +466,14 @@
                        const SmallVectorImpl<ISD::OutputArg> &Outs,
                        const SmallVectorImpl<ISD::InputArg> &Ins,
                        DebugLoc dl, SelectionDAG &DAG,
-                       SmallVectorImpl<SDValue> &InVals);
+                       SmallVectorImpl<SDValue> &InVals) const;
     SDValue
       LowerCall_SVR4(SDValue Chain, SDValue Callee,
                      CallingConv::ID CallConv, bool isVarArg, bool isTailCall,
                      const SmallVectorImpl<ISD::OutputArg> &Outs,
                      const SmallVectorImpl<ISD::InputArg> &Ins,
                      DebugLoc dl, SelectionDAG &DAG,
-                     SmallVectorImpl<SDValue> &InVals);
+                     SmallVectorImpl<SDValue> &InVals) const;
   };
 }