[RISCV] Don't emit LUI/ADDI MachineSDNodes from getAddr

Instead add RISCVISD opcodes that will be selected to LUI/ADDI
during isel.

I'm looking into maybe moving doPeepholeLoadStoreADDI into isel.
Having the ADDI as a RISCVISD node will make it visible to isel.

Reviewed By: reames

Differential Revision: https://reviews.llvm.org/D127713

Author: topperc

llvm/lib/Target/RISCV/RISCVISelLowering.cpp

@@ -3631,8 +3631,8 @@ SDValue RISCVTargetLowering::getAddr(NodeTy *N, SelectionDAG &DAG,
     // address space. This generates the pattern (addi (lui %hi(sym)) %lo(sym)).
     SDValue AddrHi = getTargetNode(N, DL, Ty, DAG, RISCVII::MO_HI);
     SDValue AddrLo = getTargetNode(N, DL, Ty, DAG, RISCVII::MO_LO);
-    SDValue MNHi = SDValue(DAG.getMachineNode(RISCV::LUI, DL, Ty, AddrHi), 0);
-    return SDValue(DAG.getMachineNode(RISCV::ADDI, DL, Ty, MNHi, AddrLo), 0);
+    SDValue MNHi = DAG.getNode(RISCVISD::HI, DL, Ty, AddrHi);
+    return DAG.getNode(RISCVISD::ADD_LO, DL, Ty, MNHi, AddrLo);
   }
   case CodeModel::Medium: {
     // Generate a sequence for accessing addresses within any 2GiB range within
@@ -11113,6 +11113,8 @@ const char *RISCVTargetLowering::getTargetNodeName(unsigned Opcode) const {
   NODE_NAME_CASE(BuildPairF64)
   NODE_NAME_CASE(SplitF64)
   NODE_NAME_CASE(TAIL)
+  NODE_NAME_CASE(ADD_LO)
+  NODE_NAME_CASE(HI)
   NODE_NAME_CASE(MULHSU)
   NODE_NAME_CASE(SLLW)
   NODE_NAME_CASE(SRAW)

llvm/lib/Target/RISCV/RISCVISelLowering.h

@@ -41,6 +41,12 @@ enum NodeType : unsigned {
   BuildPairF64,
   SplitF64,
   TAIL,
+
+  // Add the Lo 12 bits from an address. Selected to ADDI.
+  ADD_LO,
+  // Get the Hi 20 bits from an address. Selected to LUI.
+  HI,
+
   // Multiply high for signedxunsigned.
   MULHSU,
   // RV64I shifts, directly matching the semantics of the named RISC-V

llvm/lib/Target/RISCV/RISCVInstrInfo.td

@@ -83,6 +83,9 @@ def riscv_read_cycle_wide : SDNode<"RISCVISD::READ_CYCLE_WIDE",
                                    SDT_RISCVReadCycleWide,
                                    [SDNPHasChain, SDNPSideEffect]>;
 
+def riscv_add_lo : SDNode<"RISCVISD::ADD_LO", SDTIntBinOp>;
+def riscv_hi : SDNode<"RISCVISD::HI", SDTIntUnaryOp>;
+
 //===----------------------------------------------------------------------===//
 // Operand and SDNode transformation definitions.
 //===----------------------------------------------------------------------===//
@@ -1207,6 +1210,22 @@ def PseudoAddTPRel : Pseudo<(outs GPR:$rd),
 def : Pat<(FrameAddrRegImm GPR:$rs1, simm12:$imm12),
           (ADDI GPR:$rs1, simm12:$imm12)>;
 
+// HI and ADD_LO address nodes.
+
+def : Pat<(riscv_hi tglobaladdr:$in), (LUI tglobaladdr:$in)>;
+def : Pat<(riscv_hi tblockaddress:$in), (LUI tblockaddress:$in)>;
+def : Pat<(riscv_hi tjumptable:$in), (LUI tjumptable:$in)>;
+def : Pat<(riscv_hi tconstpool:$in), (LUI tconstpool:$in)>;
+
+def : Pat<(riscv_add_lo GPR:$hi, tglobaladdr:$lo),
+          (ADDI GPR:$hi, tglobaladdr:$lo)>;
+def : Pat<(riscv_add_lo GPR:$hi, tblockaddress:$lo),
+          (ADDI GPR:$hi, tblockaddress:$lo)>;
+def : Pat<(riscv_add_lo GPR:$hi, tjumptable:$lo),
+          (ADDI GPR:$hi, tjumptable:$lo)>;
+def : Pat<(riscv_add_lo GPR:$hi, tconstpool:$lo),
+          (ADDI GPR:$hi, tconstpool:$lo)>;
+
 /// Setcc
 
 def : PatGprGpr<setlt, SLT>;