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

4 files changed, 36 insertions, 35 deletions

diff --git a/lib/Target/Mips/MipsISelDAGToDAG.cpp b/lib/Target/Mips/MipsISelDAGToDAG.cpp
index c4746db..ee85a3f 100644
--- a/lib/Target/Mips/MipsISelDAGToDAG.cpp
+++ b/lib/Target/Mips/MipsISelDAGToDAG.cpp
@@ -13,7 +13,6 @@
 
 #define DEBUG_TYPE "mips-isel"
 #include "Mips.h"
-#include "MipsISelLowering.h"
 #include "MipsMachineFunction.h"
 #include "MipsRegisterInfo.h"
 #include "MipsSubtarget.h"
diff --git a/lib/Target/Mips/MipsISelLowering.cpp b/lib/Target/Mips/MipsISelLowering.cpp
index d4cbc7c..c0dea4d 100644
--- a/lib/Target/Mips/MipsISelLowering.cpp
+++ b/lib/Target/Mips/MipsISelLowering.cpp
@@ -166,7 +166,7 @@ unsigned MipsTargetLowering::getFunctionAlignment(const Function *) const {
 }
 
 SDValue MipsTargetLowering::
-LowerOperation(SDValue Op, SelectionDAG &DAG) 
+LowerOperation(SDValue Op, SelectionDAG &DAG) const
 {
   switch (Op.getOpcode()) 
   {
@@ -341,7 +341,7 @@ MipsTargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
 //===----------------------------------------------------------------------===//
 
 SDValue MipsTargetLowering::
-LowerFP_TO_SINT(SDValue Op, SelectionDAG &DAG)
+LowerFP_TO_SINT(SDValue Op, SelectionDAG &DAG) const
 {
   if (!Subtarget->isMips1())
     return Op;
@@ -374,7 +374,7 @@ LowerFP_TO_SINT(SDValue Op, SelectionDAG &DAG)
 }
 
 SDValue MipsTargetLowering::
-LowerDYNAMIC_STACKALLOC(SDValue Op, SelectionDAG &DAG)
+LowerDYNAMIC_STACKALLOC(SDValue Op, SelectionDAG &DAG) const
 {
   SDValue Chain = Op.getOperand(0);
   SDValue Size = Op.getOperand(1);
@@ -398,7 +398,7 @@ LowerDYNAMIC_STACKALLOC(SDValue Op, SelectionDAG &DAG)
 }
 
 SDValue MipsTargetLowering::
-LowerANDOR(SDValue Op, SelectionDAG &DAG)
+LowerANDOR(SDValue Op, SelectionDAG &DAG) const
 {
   SDValue LHS   = Op.getOperand(0);
   SDValue RHS   = Op.getOperand(1);
@@ -419,7 +419,7 @@ LowerANDOR(SDValue Op, SelectionDAG &DAG)
 }
 
 SDValue MipsTargetLowering::
-LowerBRCOND(SDValue Op, SelectionDAG &DAG)
+LowerBRCOND(SDValue Op, SelectionDAG &DAG) const
 {
   // The first operand is the chain, the second is the condition, the third is 
   // the block to branch to if the condition is true.
@@ -441,7 +441,7 @@ LowerBRCOND(SDValue Op, SelectionDAG &DAG)
 }
 
 SDValue MipsTargetLowering::
-LowerSETCC(SDValue Op, SelectionDAG &DAG)
+LowerSETCC(SDValue Op, SelectionDAG &DAG) const
 {
   // The operands to this are the left and right operands to compare (ops #0, 
   // and #1) and the condition code to compare them with (op #2) as a 
@@ -457,7 +457,7 @@ LowerSETCC(SDValue Op, SelectionDAG &DAG)
 }
 
 SDValue MipsTargetLowering::
-LowerSELECT(SDValue Op, SelectionDAG &DAG) 
+LowerSELECT(SDValue Op, SelectionDAG &DAG) const
 {
   SDValue Cond  = Op.getOperand(0); 
   SDValue True  = Op.getOperand(1);
@@ -481,7 +481,8 @@ LowerSELECT(SDValue Op, SelectionDAG &DAG)
                      Cond, True, False, CCNode);
 }
 
-SDValue MipsTargetLowering::LowerGlobalAddress(SDValue Op, SelectionDAG &DAG) {
+SDValue MipsTargetLowering::LowerGlobalAddress(SDValue Op,
+                                               SelectionDAG &DAG) const {
   // FIXME there isn't actually debug info here
   DebugLoc dl = Op.getDebugLoc();
   const GlobalValue *GV = cast<GlobalAddressSDNode>(Op)->getGlobal();
@@ -525,14 +526,14 @@ SDValue MipsTargetLowering::LowerGlobalAddress(SDValue Op, SelectionDAG &DAG) {
 }
 
 SDValue MipsTargetLowering::
-LowerGlobalTLSAddress(SDValue Op, SelectionDAG &DAG)
+LowerGlobalTLSAddress(SDValue Op, SelectionDAG &DAG) const
 {
   llvm_unreachable("TLS not implemented for MIPS.");
   return SDValue(); // Not reached
 }
 
 SDValue MipsTargetLowering::
-LowerJumpTable(SDValue Op, SelectionDAG &DAG) 
+LowerJumpTable(SDValue Op, SelectionDAG &DAG) const
 {
   SDValue ResNode;
   SDValue HiPart; 
@@ -560,7 +561,7 @@ LowerJumpTable(SDValue Op, SelectionDAG &DAG)
 }
 
 SDValue MipsTargetLowering::
-LowerConstantPool(SDValue Op, SelectionDAG &DAG) 
+LowerConstantPool(SDValue Op, SelectionDAG &DAG) const
 {
   SDValue ResNode;
   ConstantPoolSDNode *N = cast<ConstantPoolSDNode>(Op);
@@ -596,7 +597,7 @@ LowerConstantPool(SDValue Op, SelectionDAG &DAG)
   return ResNode;
 }
 
-SDValue MipsTargetLowering::LowerVASTART(SDValue Op, SelectionDAG &DAG) {
+SDValue MipsTargetLowering::LowerVASTART(SDValue Op, SelectionDAG &DAG) const {
   MachineFunction &MF = DAG.getMachineFunction();
   MipsFunctionInfo *FuncInfo = MF.getInfo<MipsFunctionInfo>();
 
@@ -773,7 +774,7 @@ MipsTargetLowering::LowerCall(SDValue Chain, SDValue Callee,
                               const SmallVectorImpl<ISD::OutputArg> &Outs,
                               const SmallVectorImpl<ISD::InputArg> &Ins,
                               DebugLoc dl, SelectionDAG &DAG,
-                              SmallVectorImpl<SDValue> &InVals) {
+                              SmallVectorImpl<SDValue> &InVals) const {
   // MIPs target does not yet support tail call optimization.
   isTailCall = false;
 
@@ -967,7 +968,7 @@ MipsTargetLowering::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 {
 
   // Assign locations to each value returned by this call.
   SmallVector<CCValAssign, 16> RVLocs;
@@ -999,7 +1000,8 @@ MipsTargetLowering::LowerFormalArguments(SDValue Chain,
                                         const SmallVectorImpl<ISD::InputArg>
                                         &Ins,
                                         DebugLoc dl, SelectionDAG &DAG,
-                                        SmallVectorImpl<SDValue> &InVals) {
+                                        SmallVectorImpl<SDValue> &InVals)
+                                          const {
 
   MachineFunction &MF = DAG.getMachineFunction();
   MachineFrameInfo *MFI = MF.getFrameInfo();
@@ -1171,7 +1173,7 @@ SDValue
 MipsTargetLowering::LowerReturn(SDValue Chain,
                                 CallingConv::ID CallConv, bool isVarArg,
                                 const SmallVectorImpl<ISD::OutputArg> &Outs,
-                                DebugLoc dl, SelectionDAG &DAG) {
+                                DebugLoc dl, SelectionDAG &DAG) const {
 
   // CCValAssign - represent the assignment of
   // the return value to a location
diff --git a/lib/Target/Mips/MipsISelLowering.h b/lib/Target/Mips/MipsISelLowering.h
index 0c5421f..43af325 100644
--- a/lib/Target/Mips/MipsISelLowering.h
+++ b/lib/Target/Mips/MipsISelLowering.h
@@ -72,7 +72,7 @@ namespace llvm {
     explicit MipsTargetLowering(MipsTargetMachine &TM);
 
     /// LowerOperation - Provide custom lowering hooks for some operations.
-    virtual SDValue LowerOperation(SDValue Op, SelectionDAG &DAG);
+    virtual SDValue LowerOperation(SDValue Op, SelectionDAG &DAG) const;
 
     /// getTargetNodeName - This method returns the name of a target specific 
     //  DAG node.
@@ -93,27 +93,27 @@ namespace llvm {
                             CallingConv::ID CallConv, bool isVarArg,
                             const SmallVectorImpl<ISD::InputArg> &Ins,
                             DebugLoc dl, SelectionDAG &DAG,
-                            SmallVectorImpl<SDValue> &InVals);
+                            SmallVectorImpl<SDValue> &InVals) const;
 
     // Lower Operand specifics
-    SDValue LowerANDOR(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerBRCOND(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerConstantPool(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerDYNAMIC_STACKALLOC(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerFP_TO_SINT(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerGlobalAddress(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerGlobalTLSAddress(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerJumpTable(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerSELECT(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerSETCC(SDValue Op, SelectionDAG &DAG);
-    SDValue LowerVASTART(SDValue Op, SelectionDAG &DAG);
+    SDValue LowerANDOR(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerBRCOND(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerConstantPool(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerDYNAMIC_STACKALLOC(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerFP_TO_SINT(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 LowerSELECT(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerSETCC(SDValue Op, SelectionDAG &DAG) const;
+    SDValue LowerVASTART(SDValue Op, SelectionDAG &DAG) 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,
@@ -122,13 +122,13 @@ namespace llvm {
                 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;
 
     virtual MachineBasicBlock *EmitInstrWithCustomInserter(MachineInstr *MI,
                                                          MachineBasicBlock *MBB,
diff --git a/lib/Target/Mips/MipsTargetMachine.h b/lib/Target/Mips/MipsTargetMachine.h
index c3428be..cd671cf 100644
--- a/lib/Target/Mips/MipsTargetMachine.h
+++ b/lib/Target/Mips/MipsTargetMachine.h
@@ -47,8 +47,8 @@ namespace llvm {
       return &InstrInfo.getRegisterInfo();
     }
 
-    virtual MipsTargetLowering   *getTargetLowering() const { 
-      return const_cast<MipsTargetLowering*>(&TLInfo); 
+    virtual const MipsTargetLowering *getTargetLowering() const { 
+      return &TLInfo;
     }
 
     // Pass Pipeline Configuration