[BPF] TableGen-erate SDNode descriptions (llvm#166499)

This allows SDNodes to be validated against their expected type profiles
and reduces the number of changes required to add a new node.

Fix BR_CC/MEMCPY descriptions to match C++ code that creates the nodes
(an error detected by the enabled verification functionality).

Also remove redundant `SDNPOutGlue` on `BPFISD::MEMCPY`.

Part of llvm#119709.

Author: s-barannikov

llvm/lib/Target/BPF/BPFISelLowering.cpp

@@ -803,26 +803,6 @@ SDValue BPFTargetLowering::LowerJumpTable(SDValue Op, SelectionDAG &DAG) const {
   return getAddr(N, DAG);
 }
 
-const char *BPFTargetLowering::getTargetNodeName(unsigned Opcode) const {
-  switch ((BPFISD::NodeType)Opcode) {
-  case BPFISD::FIRST_NUMBER:
-    break;
-  case BPFISD::RET_GLUE:
-    return "BPFISD::RET_GLUE";
-  case BPFISD::CALL:
-    return "BPFISD::CALL";
-  case BPFISD::SELECT_CC:
-    return "BPFISD::SELECT_CC";
-  case BPFISD::BR_CC:
-    return "BPFISD::BR_CC";
-  case BPFISD::Wrapper:
-    return "BPFISD::Wrapper";
-  case BPFISD::MEMCPY:
-    return "BPFISD::MEMCPY";
-  }
-  return nullptr;
-}
-
 static SDValue getTargetNode(ConstantPoolSDNode *N, const SDLoc &DL, EVT Ty,
                              SelectionDAG &DAG, unsigned Flags) {
   return DAG.getTargetConstantPool(N->getConstVal(), Ty, N->getAlign(),

llvm/lib/Target/BPF/BPFISelLowering.h

@@ -20,17 +20,6 @@
 
 namespace llvm {
 class BPFSubtarget;
-namespace BPFISD {
-enum NodeType : unsigned {
-  FIRST_NUMBER = ISD::BUILTIN_OP_END,
-  RET_GLUE,
-  CALL,
-  SELECT_CC,
-  BR_CC,
-  Wrapper,
-  MEMCPY
-};
-}
 
 class BPFTargetLowering : public TargetLowering {
 public:
@@ -39,9 +28,6 @@ class BPFTargetLowering : public TargetLowering {
   // Provide custom lowering hooks for some operations.
   SDValue LowerOperation(SDValue Op, SelectionDAG &DAG) const override;
 
-  // This method returns the name of a target specific DAG node.
-  const char *getTargetNodeName(unsigned Opcode) const override;
-
   // This method decides whether folding a constant offset
   // with the given GlobalAddress is legal.
   bool isOffsetFoldingLegal(const GlobalAddressSDNode *GA) const override;

llvm/lib/Target/BPF/BPFInstrInfo.td

@@ -41,14 +41,12 @@ def BPFcallseq_start: SDNode<"ISD::CALLSEQ_START", SDT_BPFCallSeqStart,
                              [SDNPHasChain, SDNPOutGlue]>;
 def BPFcallseq_end  : SDNode<"ISD::CALLSEQ_END",   SDT_BPFCallSeqEnd,
                              [SDNPHasChain, SDNPOptInGlue, SDNPOutGlue]>;
-def BPFbrcc         : SDNode<"BPFISD::BR_CC", SDT_BPFBrCC,
-                             [SDNPHasChain, SDNPOutGlue, SDNPInGlue]>;
+def BPFbrcc         : SDNode<"BPFISD::BR_CC", SDT_BPFBrCC, [SDNPHasChain]>;
 
 def BPFselectcc     : SDNode<"BPFISD::SELECT_CC", SDT_BPFSelectCC>;
 def BPFWrapper      : SDNode<"BPFISD::Wrapper", SDT_BPFWrapper>;
 def BPFmemcpy       : SDNode<"BPFISD::MEMCPY", SDT_BPFMEMCPY,
-                             [SDNPHasChain, SDNPInGlue, SDNPOutGlue,
-                              SDNPMayStore, SDNPMayLoad]>;
+                             [SDNPHasChain, SDNPMayStore, SDNPMayLoad]>;
 def BPFIsLittleEndian : Predicate<"Subtarget->isLittleEndian()">;
 def BPFIsBigEndian    : Predicate<"!Subtarget->isLittleEndian()">;
 def BPFHasALU32 : Predicate<"Subtarget->getHasAlu32()">;

llvm/lib/Target/BPF/BPFSelectionDAGInfo.cpp

@@ -10,12 +10,20 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "BPFSelectionDAGInfo.h"
 #include "BPFTargetMachine.h"
 #include "llvm/CodeGen/SelectionDAG.h"
+
+#define GET_SDNODE_DESC
+#include "BPFGenSDNodeInfo.inc"
+
 using namespace llvm;
 
 #define DEBUG_TYPE "bpf-selectiondag-info"
 
+BPFSelectionDAGInfo::BPFSelectionDAGInfo()
+    : SelectionDAGGenTargetInfo(BPFGenSDNodeInfo) {}
+
 SDValue BPFSelectionDAGInfo::EmitTargetCodeForMemcpy(
     SelectionDAG &DAG, const SDLoc &dl, SDValue Chain, SDValue Dst, SDValue Src,
     SDValue Size, Align Alignment, bool isVolatile, bool AlwaysInline,
@@ -31,11 +39,7 @@ SDValue BPFSelectionDAGInfo::EmitTargetCodeForMemcpy(
   if (StoresNumEstimate > getCommonMaxStoresPerMemFunc())
     return SDValue();
 
-  SDVTList VTs = DAG.getVTList(MVT::Other, MVT::Glue);
-
-  Dst = DAG.getNode(BPFISD::MEMCPY, dl, VTs, Chain, Dst, Src,
-                    DAG.getConstant(CopyLen, dl, MVT::i64),
-                    DAG.getConstant(Alignment.value(), dl, MVT::i64));
-
-  return Dst.getValue(0);
+  return DAG.getNode(BPFISD::MEMCPY, dl, MVT::Other, Chain, Dst, Src,
+                     DAG.getConstant(CopyLen, dl, MVT::i64),
+                     DAG.getConstant(Alignment.value(), dl, MVT::i64));
 }

llvm/lib/Target/BPF/BPFSelectionDAGInfo.h

@@ -15,10 +15,15 @@
 
 #include "llvm/CodeGen/SelectionDAGTargetInfo.h"
 
+#define GET_SDNODE_ENUM
+#include "BPFGenSDNodeInfo.inc"
+
 namespace llvm {
 
-class BPFSelectionDAGInfo : public SelectionDAGTargetInfo {
+class BPFSelectionDAGInfo : public SelectionDAGGenTargetInfo {
 public:
+  BPFSelectionDAGInfo();
+
   SDValue EmitTargetCodeForMemcpy(SelectionDAG &DAG, const SDLoc &dl,
                                   SDValue Chain, SDValue Dst, SDValue Src,
                                   SDValue Size, Align Alignment,
@@ -27,9 +32,8 @@ class BPFSelectionDAGInfo : public SelectionDAGTargetInfo {
                                   MachinePointerInfo SrcPtrInfo) const override;
 
   unsigned getCommonMaxStoresPerMemFunc() const { return 128; }
-
 };
 
-}
+} // namespace llvm
 
 #endif

llvm/lib/Target/BPF/CMakeLists.txt

@@ -10,6 +10,7 @@ tablegen(LLVM BPFGenDisassemblerTables.inc -gen-disassembler)
 tablegen(LLVM BPFGenInstrInfo.inc -gen-instr-info)
 tablegen(LLVM BPFGenMCCodeEmitter.inc -gen-emitter)
 tablegen(LLVM BPFGenRegisterInfo.inc -gen-register-info)
+tablegen(LLVM BPFGenSDNodeInfo.inc -gen-sd-node-info)
 tablegen(LLVM BPFGenSubtargetInfo.inc -gen-subtarget)
 tablegen(LLVM BPFGenGlobalISel.inc -gen-global-isel)
 tablegen(LLVM BPFGenRegisterBank.inc -gen-register-bank)