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BundleChecker.scala 21.3 KB
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package uvm.staticanalysis

import org.slf4j.LoggerFactory

import com.typesafe.scalalogging.Logger

import uvm._
import uvm.ssavariables._
import uvm.types._

object BundleChecker {
  val logger: Logger = Logger(LoggerFactory.getLogger(getClass.getName))

  implicit class RichMuTypes(val tys1: Seq[Type]) extends AnyVal {
    def shallowEq(tys2: Seq[Type]): Boolean = {
      tys1.size == tys2.size && ((tys1 zip tys2).map {
        case (ty1, ty2) => ty1 shallowEq ty2
      }).foldLeft(true)((x, y) => x && y)
    }
  }

  implicit class RichMuType(val ty1: Type) extends AnyVal {
    def shallowEq(ty2: Type): Boolean = {
      (ty1, ty2) match {
        case (TypeInt(l1), TypeInt(l2))                     => l1 == l2
        case (TypeFloat(), TypeFloat())                     => true
        case (TypeDouble(), TypeDouble())                   => true
        case (TypeUPtr(_), TypeUPtr(_))                     => true
        case (TypeUFuncPtr(_), TypeUFuncPtr(_))             => true
        case (TypeVoid(), TypeVoid())                       => true
        case (TypeRef(_), TypeRef(_))                       => true
        case (TypeIRef(_), TypeIRef(_))                     => true
        case (TypeWeakRef(_), TypeWeakRef(_))               => true
        case (TypeTagRef64(), TypeTagRef64())               => true
        case (TypeFuncRef(_), TypeFuncRef(_))               => true
        case (TypeThreadRef(), TypeThreadRef())             => true
        case (TypeStackRef(), TypeStackRef())               => true
        case (TypeFrameCursorRef(), TypeFrameCursorRef())   => true
        case (TypeIRBuilderRef(), TypeIRBuilderRef())       => true
        case (TypeStruct(tys1), TypeStruct(tys2))           => tys1 shallowEq tys2
        case (TypeHybrid(fts1, vt1), TypeHybrid(fts2, vt2)) => (fts1 shallowEq fts2) && (vt1 shallowEq vt2)
        case (TypeArray(et1, l1), TypeArray(et2, l2))       => (et1 shallowEq et2) && (l1 == l2)
        case (TypeVector(et1, l1), TypeVector(et2, l2))     => (et1 shallowEq et2) && (l1 == l2)
        case others                                         => false
      }
    }
  }

  val INT_CMP_OPS = {
    import CmpOptr._
    Seq(EQ, NE, ULT, ULE, UGT, UGE, SLT, SLE, SGT, SGE)
  }

  val FP_CMP_OPS = {
    import CmpOptr._
    Seq(FTRUE, FFALSE, FORD, FOEQ, FONE, FOLT, FOLE, FOGT, FOGE,
      FUNO, FUEQ, FUNE, FULT, FULE, FUGT, FUGE)
  }
}

class BundleChecker {
  import BundleChecker._

  type MutableSet[T] = collection.mutable.HashSet[T]
  val MutableSet = collection.mutable.HashSet
  type MutableMap[K, V] = collection.mutable.HashMap[K, V]
  val MutableMap = collection.mutable.HashMap
  type MutableQueue[T] = collection.mutable.Queue[T]
  val MutableQueue = collection.mutable.Queue
  type MutableStack[T] = collection.mutable.Stack[T]
  val MutableStack = collection.mutable.Stack

  def checkBundle(bundle: Bundle, parentBundle: Option[GlobalBundle]): Unit = {
    new BundleChecker(bundle, parentBundle).check()
  }

  class BundleChecker(bundle: Bundle, parentBundle: Option[GlobalBundle]) {
    def check(): Unit = {
      checkTypes()
      checkSigs()
      checkConsts()
      checkGlobals()
      checkExpFuncs()
      checkFuncs()
    }

    def checkTypes(): Unit = {
      val compositeTypes = bundle.typeNs.all.flatMap {
        case ty: AbstractCompositeType => Some(ty)
        case _                         => None
      }.toSeq
      checkCompositeTypesNotRecursive(compositeTypes)
    }

    def checkCompositeTypesNotRecursive(compTys: Seq[AbstractCompositeType]): Unit = {
      val world = MutableSet(compTys: _*) // All types in this bundle. Assume all other types are valid.
      val visited = MutableSet[Type]()

      for (rootTy <- world if !visited.contains(rootTy)) {
        val inStack = MutableSet[AbstractCompositeType]()

        def visit(ty: AbstractCompositeType): Unit = {
          logger.debug("Checking composite type %s".format(ty.repr))
          visited(ty) = true
          inStack(ty) = true
          val succs = ty match {
            case TypeStruct(fieldTys)        => fieldTys
            case TypeArray(elemTy, _)        => Seq(elemTy)
            case TypeVector(elemTy, _)       => Seq(elemTy)
            case TypeHybrid(fixedTys, varTy) => fixedTys ++ Seq(varTy)
          }

          succs foreach {
            case succ @ TypeHybrid(fixedTys, varTy) =>
              throw error("Composite type %s contains hybrid %s".format(ty.repr, succ.repr),
                pretty = Seq(ty, succ))
            case succ @ TypeVoid() =>
              throw error("Composite type %s contains void %s".format(ty.repr, succ.repr),
                pretty = Seq(ty, succ))
            case succ: AbstractCompositeType => {
              if (inStack(succ)) {
                throw error("Composite type %s contains itself or its parent %s".format(ty.repr, succ.repr),
                  pretty = Seq(ty, succ))
              } else if (!visited(succ) && world.contains(succ)) {
                visit(succ)
              } else {
                // Ignore visited or out-of-bundle types.
              }
            }
            case _ => // do nothing if it is not composite
          }
          inStack(ty) = false
        }

        visit(rootTy)
      }
    }

    def checkValueType(ty: Type): Unit = {
      val invalidTypeKind = ty match {
        case _: TypeWeakRef => Some("weak reference")
        case _: TypeHybrid  => Some("hybrid")
        case _: TypeVoid    => Some("void")
        case _              => None
      }

      invalidTypeKind.foreach { kind =>
        throw error("%s %s cannot be the type of an SSA variable".format(kind, ty.repr),
          pretty = Seq(ty))
      }
    }

    def checkSigs(): Unit = {
      for (sig <- bundle.funcSigNs.all) {
        checkSig(sig)
      }
    }

    def checkSig(sig: FuncSig): Unit = {
      for (ty <- sig.paramTys ++ sig.retTys) try {
        checkValueType(ty)
      } catch {
        case e: StaticCheckingException => throw error("In function signature %s: %s".format(sig.repr, e.getMessage),
          pretty = Seq(sig), cause = e.getCause)
      }
    }

    def sigArityMatch(sig1: FuncSig, sig2: FuncSig): Boolean = {
      sig1.paramTys.length == sig2.paramTys.length && sig1.retTys.length == sig2.retTys.length
    }

    def checkConsts(): Unit = {
      for (c <- bundle.constantNs.all) {
        checkScalarConst(c)
      }
      val compositeConsts = bundle.constantNs.all.flatMap {
        case c: ConstSeq => Some(c)
        case _           => None
      }.toSeq
      checkCompositeConstantsNotRecursive(compositeConsts)
    }

    def checkScalarConst(c: Constant): Unit = {
      c match {
        case cc @ ConstInt(ty, _) => ty match {
          case TypeInt(_)      =>
          case TypeUPtr(_)     =>
          case TypeUFuncPtr(_) =>
          case _ => {
            throw error("Constant %s: int literal is not suitable for type %s".format(c.repr, ty.repr),
              pretty = Seq(c, ty))
          }
        }
        case cc @ ConstFloat(ty, _) => ty match {
          case TypeFloat() =>
          case _ => {
            throw error("Constant %s: float literal is not suitable for type %s".format(c.repr, ty.repr),
              pretty = Seq(c, ty))
          }
        }
        case cc @ ConstDouble(ty, _) => ty match {
          case TypeDouble() =>
          case _ => {
            throw error("Constant %s: double literal is not suitable for type %s".format(c.repr, ty.repr),
              pretty = Seq(c, ty))
          }
        }
        case cc @ ConstNull(ty) => ty match {
          case TypeRef(_)  =>
          case TypeIRef(_) =>
          case TypeWeakRef(_) => {
            throw error("Constant %s: type %s is a weakref, which cannot have values.".format(c.repr, ty.repr),
              pretty = Seq(c, ty))
          }
          case TypeFuncRef(_)       =>
          case TypeStackRef()       =>
          case TypeThreadRef()      =>
          case TypeFrameCursorRef() =>
          case _ => {
            throw error("Constant %s: NULL literal is not suitable for type %s".format(c.repr, ty.repr),
              pretty = Seq(c, ty))
          }
        }
        case cc @ ConstSeq(ty, elems) => // Ignore for now
        case cc @ ConstExtern(ty, _) => ty match {
          case TypeUPtr(_)     =>
          case TypeUFuncPtr(_) =>
          case _ => {
            throw error("Constant %s: external constant is not suitable for type %s".format(c.repr, ty.repr),
              pretty = Seq(c, ty))
          }
        }
      }
    }

    def checkCompositeConstantsNotRecursive(compConsts: Seq[ConstSeq]): Unit = {
      val world = MutableSet(compConsts: _*) // All ConstSeq instances in this bundle. Assume all other constants are valid.
      val visited = MutableSet[ConstSeq]()

      for (rootConst <- world if !visited.contains(rootConst)) {
        val inStack = MutableSet[ConstSeq]()

        def visit(c: ConstSeq): Unit = {
          logger.debug("Checking composite constant %s".format(c.repr))
          visited(c) = true
          inStack(c) = true
          val succs = c match {
            case ConstSeq(ty, elems) => {
              val expectedArity = ty match {
                case t @ TypeStruct(fieldTys)   => fieldTys.length
                case t @ TypeArray(elemTy, sz)  => sz
                case t @ TypeVector(elemTy, sz) => sz
                case _ => throw error("Constant %s: sequence literal is not suitable for type %s".format(c.repr, ty.repr),
                  pretty = Seq(c, ty))
              }

              val actualArity = elems.length
              if (actualArity != expectedArity) {
                throw error("Constant %s: type %s expects %d elements, but %d found".format(c.repr, ty.repr,
                  expectedArity, actualArity), pretty = Seq(c, ty))
              }

              elems
            }
          }

          succs foreach {
            case succ: ConstSeq => {
              if (inStack(succ)) {
                throw error("Constant %s contains itself or its parent %s".format(c.repr, succ.repr),
                  pretty = Seq(c, succ))
              } else if (!visited.contains(succ) && world.contains(succ)) {
                visit(succ)
              } else {
                // Ignore visited or out-of-bundle types.
              }
            }
            case _ => // do nothing if it is not composite
          }
          inStack(c) = false
        }

        visit(rootConst)
      }
    }

    def lookupSourceInfo(obj: AnyRef): SourceInfo = {
      val si1 = bundle.sourceInfoRepo(obj)
      if (si1 == NoSourceInfo && parentBundle.isDefined) {
        return parentBundle.get.sourceInfoRepo(obj)
      } else {
        return si1
      }
    }

    def error(msg: String, pretty: Seq[AnyRef] = Seq(), cause: Throwable = null): StaticCheckingException = {
      val prettyMsgs = pretty.map(o => lookupSourceInfo(o).prettyPrint())
      new StaticCheckingException("%s\n%s".format(msg, prettyMsgs.mkString("\n")), cause)
    }

    def checkGlobals(): Unit = {
      for (g <- bundle.globalCellNs.all) {
        g.cellTy match {
          case ty: TypeVoid => throw error("Global cell %s: Global cell cannot have void type.".format(g.repr),
            pretty = Seq(g, ty))
          case ty: TypeHybrid => throw error("Global cell %s: Global cell cannot have hybrid type.".format(g.repr),
            pretty = Seq(g, ty))
          case _ =>
        }
      }
    }

    def checkExpFuncs(): Unit = {
      for (ef <- bundle.expFuncNs.all) {
        ef.cookie.constTy match {
          case TypeInt(64) =>
          case ty => throw error("Exposed function %s: cookie must be a 64-bit int. %s found.".format(ef.repr, ty.repr),
            pretty = Seq(ef, ty))
        }
      }
    }

    def checkFuncs(): Unit = {
      for (fv <- bundle.funcVerNs.all) {
        checkFuncVer(fv)
      }
    }

    def checkFuncVer(fv: FuncVer): Unit = {
      val sig = fv.sig
      val fsig = fv.func.sig
      if (!sigArityMatch(sig, fsig)) {
        throw error("Function version %s has different parameter or return value arity as its function %s".format(
          fv.repr, fv.func.repr), pretty = Seq(fv, sig, fv.func, fsig))
      }

      val entry = fv.entry
      if (entry.norParams.length != sig.paramTys.length) {
        throw error("Function version %s: the entry block has %d parameters, but the function takes %s parameters."
          .format(fv.repr, entry.norParams.length, sig.paramTys.length),
          pretty = Seq(fv, entry, sig))
      }

      if (entry.excParam.isDefined) {
        throw error("Function version %s: the entry block should not have exceptional parameter."
          .format(fv.repr),
          pretty = Seq(entry))
      }

      for (bb <- fv.bbs) {
        checkBasicBlock(fv, entry, bb)
      }
    }

    def checkBasicBlock(fv: FuncVer, entry: BasicBlock, bb: BasicBlock): Unit = {
      if (bb.insts.isEmpty) {
        throw error("Function version %s: basic block %s is empty"
          .format(fv.repr, bb.repr),
          pretty = Seq(bb))
      }
      val lastInst = bb.insts.last match {
        case i: MaybeTerminator if i.canTerminate => i
        case i => throw error("FuncVer %s BB %s: The last instruction %s is not a valid basic block terminator"
          .format(fv.repr, bb.repr, i.repr),
          pretty = Seq(i))
      }

      implicit val _fv = fv
      implicit val _bb = bb
      implicit val _i: Instruction = lastInst

      lastInst match {
        case i: InstRet => {
          val retVals = i.retVals
          val nrv = retVals.length
          val nrvSig = fv.sig.retTys.length
          if (nrv != nrvSig) {
            throw errorFBI("Returning wrong number of values. expected: %d, found: %d"
              .format(nrvSig, nrv),
              pretty = Seq(i, fv, fv.sig))
          }
        }
        case _ =>
      }

      for ((dest, isNormal) <- bbDests(lastInst)) {
        if (dest.bb == entry) {
          throw error("FuncVer %s BB %s Inst %s: Cannot branch to the entry block"
            .format(fv.repr, bb.repr, lastInst.repr),
            pretty = Seq(lastInst))
        }

        val destBB = dest.bb
        val nParams = destBB.norParams.length
        val nArgs = dest.args.length
        if (nParams != nArgs) {
          throw errorFBI(("Destination %s has %d normal parameters, but %d arguments found.\n" +
            "DestClause: %s")
            .format(destBB.repr, nParams, nArgs, dest),
            pretty = Seq(lastInst, destBB))
        }

        if (isNormal) {
          if (destBB.excParam.isDefined) {
            throw errorFBI(("Normal destination %s should not have exceptional parameter.\n" +
              "DestClause: %s")
              .format(destBB.repr, dest),
              pretty = Seq(lastInst, destBB))
          }
        }
      }

      for (i <- bb.insts.init) {
        checkInst(fv, bb, i)
      }
    }

    /** Error in a funcver, basic block and an instruction. */
    def errorFBI(msg: String, pretty: Seq[AnyRef] = Seq(), cause: Throwable = null)(
      implicit fv: FuncVer, bb: BasicBlock, inst: Instruction): StaticCheckingException = {
      val appendedMsg = msg + ("\nIn FuncVer %s BB %s Inst %s %s".format(fv.repr, bb.repr, inst.repr, inst))
      error(appendedMsg, pretty, cause)
    }

    def bbDests(lastInst: MaybeTerminator): Seq[(DestClause, Boolean)] = lastInst match {
      case i: InstBranch     => Seq(i.dest).map(d => (d, true))
      case i: InstBranch2    => Seq(i.ifTrue, i.ifFalse).map(d => (d, true))
      case i: InstSwitch     => i.cases.map(_._2).map(d => (d, true))
      case i: InstTailCall   => Seq()
      case i: InstRet        => Seq()
      case i: InstThrow      => Seq()
      case i: InstWatchPoint => Seq(i.dis, i.ena).map(d => (d, true)) ++ i.exc.map(d => (d, false)).toSeq
      case i: InstWPBranch   => Seq(i.dis, i.ena).map(d => (d, true))
      case i: HasExcClause   => i.excClause.map(e => Seq((e.nor, true), (e.exc, false))).getOrElse(Seq())
    }

    def checkInst(fv: FuncVer, bb: BasicBlock, i: Instruction): Unit = {
      implicit val _fv = fv
      implicit val _bb = bb
      implicit val _inst = i
      i match {
        case i: MaybeTerminator if i.canTerminate =>
          throw errorFBI("Instruction %s is a terminator and must be the last instruction of a basic block."
            .format(i.repr),
            pretty = Seq(i))
        case i: CallLike => {
          i match {
            case c: AbstractCall =>
              i.callee match {
                case sf: Function if (!sigArityMatch(i.sig, sf.sig)) =>
                  throw errorFBI("Static callee %s has different parameter or return value arity as expected by the call site %s".format(
                    sf.repr, i), pretty = Seq(i, i.sig, sf, sf.sig))
                case _ => // Only check for static call sites
              }
            case _ => // Only check Mu-to-Mu calls, not CCALL
          }
          val nargs = i.argList.length
          val nparams = i.sig.paramTys.length
          if (nargs != nparams) {
            throw errorFBI("Call site %s has %d arguments, but %d parameters are expected.\nInstruction: %s"
              .format(i.repr, nargs, nparams, i.toString),
              pretty = Seq(i, i.sig))
          }
        }
        case i: InstBinOp => {
          import BinOptr._
          i.op match {
            case ADD | SUB | MUL | UDIV | SDIV | UREM | SREM | SHL | LSHR | ASHR | AND | OR | XOR => i.opndTy match {
              case TypeInt(_)                =>
              case TypeVector(TypeInt(_), _) =>
              case ty => {
                throw errorFBI(s"Operand type for integer operator ${i.op} cannot be ${ty}")
              }
            }
            case FADD | FSUB | FMUL | FDIV | FREM => i.opndTy match {
              case _: AbstractFPType                =>
              case TypeVector(_: AbstractFPType, _) =>
              case ty => {
                throw errorFBI(s"Operand type for FP operator ${i.op} cannot be ${ty}")
              }
            }
          }

          if (!(i.op1.inferredType shallowEq i.opndTy)) {
            throw errorFBI(s"LHS ${i.op1} has type ${i.op1.inferredType}, which does not match the operand type ${i.opndTy}")
          }

          if (!(i.op2.inferredType shallowEq i.opndTy)) {
            throw errorFBI(s"RHS ${i.op1} has type ${i.op1.inferredType}, which does not match the operand type ${i.opndTy}")
          }

          val nResults = i.results.length
          val nFlags = BinOpStatus.numOfFlags(i.flags)
          val nExpectedResults = nFlags + 1

          if (nResults != nExpectedResults) {
            throw errorFBI("BinOp %s has %d flags, thus should have %d results. Actual results: %d\nInstruction: %s"
              .format(i.repr, nFlags, nExpectedResults, nResults, i.toString),
              pretty = Seq(i))
          }

          if ((i.opndTy.isInstanceOf[TypeVector] || i.opndTy.isInstanceOf[AbstractFPType]) && nFlags != 0) {
            throw errorFBI("The operand type of BinOp %s is vector or floating point type, thus it should not have any flags. Actual flags: %d\nInstruction: %s"
              .format(i.repr, nFlags, i.toString),
              pretty = Seq(i))
          }

          if ((i.flags & (BOS_C | BOS_V)) != 0 && !Seq(BinOptr.ADD, BinOptr.SUB, BinOptr.MUL).contains(i.op)) {
            throw errorFBI("In Binop %s, flags #C and #V are only applicable to ADD, SUB and MUL. Actual operator: %s\nInstruction: %s"
              .format(i.repr, i.op, i.toString),
              pretty = Seq(i))
          }
        }
        case i: InstCmp => {
          import CmpOptr._
          i.op match {
            case EQ | NE => i.opndTy match {
              case t: AbstractEQComparableType                =>
              case TypeVector(t: AbstractEQComparableType, _) =>
              case ty => {
                throw errorFBI(s"Type ${ty} cannot be compared by operator ${i.op}. Need EQ-comparable type")
              }
            }
            case ULT | ULE | UGT | UGE => i.opndTy match {
              case t: AbstractULTComparableType                =>
              case TypeVector(t: AbstractULTComparableType, _) =>
              case ty => {
                throw errorFBI(s"Type ${ty} cannot be compared by operator ${i.op}. Need ULT-comparable type")
              }
            }
            case SLT | SLE | SGT | SGE => i.opndTy match {
              case TypeInt(_)                =>
              case TypeVector(TypeInt(_), _) =>
              case ty => {
                throw errorFBI(s"Type ${ty} cannot be compared by operator ${i.op}. Need int type")
              }
            }
            case FTRUE | FFALSE | FORD | FOEQ | FONE | FOLT | FOLE | FOGT | FOGE | FUNO |
              FUEQ | FUNE | FULT | FULE | FUGT | FUGE => i.opndTy match {
              case t: AbstractFPType                =>
              case TypeVector(t: AbstractFPType, _) =>
              case ty => {
                throw errorFBI(s"Type ${ty} cannot be compared by operator ${i.op}. Need FP type")
              }
            }
          }

          if (!(i.op1.inferredType shallowEq i.opndTy)) {
            throw errorFBI(s"LHS ${i.op1} has type ${i.op1.inferredType}, which does not match the operand type ${i.opndTy}")
          }

          if (!(i.op2.inferredType shallowEq i.opndTy)) {
            throw errorFBI(s"RHS ${i.op1} has type ${i.op1.inferredType}, which does not match the operand type ${i.opndTy}")
          }
        }
        case _ =>
      }
    }
  }
}

class StaticCheckingException(message: String = null, cause: Throwable = null) extends UvmException(message, cause)