compiler: first attempt at restructuring

compiler/src/main/kotlin/gay/pizza/pork/compiler/CodeBuilder.kt

@@ -0,0 +1,43 @@
+package gay.pizza.pork.compiler
+
+import gay.pizza.pork.bytecode.MutableRel
+import gay.pizza.pork.bytecode.Op
+import gay.pizza.pork.bytecode.Opcode
+
+class CodeBuilder(val symbol: CompilableSymbol) {
+  private val ops = mutableListOf<StubOp>()
+
+  val localState: LocalState = LocalState(symbol)
+
+  fun nextOpInst(): UInt = ops.size.toUInt()
+
+  fun emit(op: StubOp) {
+    ops.add(op)
+  }
+
+  fun emit(op: Op) {
+    ops.add(StaticOp(op))
+  }
+
+  fun emit(code: Opcode, arguments: List<UInt>) {
+    emit(Op(code, arguments))
+  }
+
+  fun emit(code: Opcode) {
+    emit(code, emptyList())
+  }
+
+  fun patch(code: Opcode, arguments: List<UInt>, index: Int, symbol: CompilableSymbol, rel: MutableRel) {
+    emit(PatchRelOp(Op(code, arguments), index, symbol, rel))
+  }
+
+  fun patch(code: Opcode, arguments: List<UInt>, index: Int, symbol: CompilableSymbol, rel: UInt) {
+    emit(PatchRelOp(Op(code, arguments), index, symbol, MutableRel(rel)))
+  }
+
+  fun patch(code: Opcode, arguments: List<UInt>, patches: Map<Int, CompilableSymbol>) {
+    ops.add(PatchSymOp(Op(code, arguments), patches))
+  }
+
+  fun build(): List<StubOp> = ops.toList()
+}

compiler/src/main/kotlin/gay/pizza/pork/compiler/CompilableSlab.kt

@@ -10,7 +10,7 @@ class CompilableSlab(val compiler: Compiler, val slab: Slab) {
     }
   }
 
-  fun compilableSymbolOf(symbol: Symbol): CompilableSymbol? = compilableSymbols.firstOrNull {
+  fun resolve(symbol: Symbol): CompilableSymbol? = compilableSymbols.firstOrNull {
     it.scopeSymbol.symbol == symbol
   }
 }

compiler/src/main/kotlin/gay/pizza/pork/compiler/CompilableSymbol.kt

@@ -24,7 +24,7 @@ class CompilableSymbol(val compilableSlab: CompilableSlab, val scopeSymbol: Scop
     }
     emitter.visit(what)
     emitter.exit()
-    return emitter.ops()
+    return emitter.code.build()
   }
 
   val id: String

compiler/src/main/kotlin/gay/pizza/pork/compiler/Compiler.kt

@@ -13,7 +13,7 @@ class Compiler {
 
   fun resolveOrNull(scopeSymbol: ScopeSymbol): CompilableSymbol? {
     val compiledSlab = compilableSlabs.of(scopeSymbol.slabScope.slab)
-    return compiledSlab.compilableSymbolOf(scopeSymbol.symbol)
+    return compiledSlab.resolve(scopeSymbol.symbol)
   }
 
   fun resolve(scopeSymbol: ScopeSymbol): CompilableSymbol = resolveOrNull(scopeSymbol) ?:

compiler/src/main/kotlin/gay/pizza/pork/compiler/Loadable.kt

@@ -0,0 +1,6 @@
+package gay.pizza.pork.compiler
+
+class Loadable(
+  val call: CompilableSymbol? = null,
+  val stubVar: StubVar? = null
+)

compiler/src/main/kotlin/gay/pizza/pork/compiler/LocalState.kt

@@ -0,0 +1,55 @@
+package gay.pizza.pork.compiler
+
+import gay.pizza.pork.ast.gen.Symbol
+import gay.pizza.pork.bytecode.MutableRel
+
+class LocalState(val symbol: CompilableSymbol) {
+  private var internalLoopState: LoopState? = null
+  val loopState: LoopState?
+    get() = internalLoopState
+
+  private var localVarIndex: UInt = 0u
+  private val variables = mutableListOf<MutableList<StubVar>>()
+
+  fun startLoop(startOfLoop: UInt, exitJumpTarget: MutableRel) {
+    internalLoopState = LoopState(
+      startOfLoop = startOfLoop,
+      exitJumpTarget = exitJumpTarget,
+      scopeDepth = (internalLoopState?.scopeDepth ?: 0u) + 1u,
+      enclosing = internalLoopState
+    )
+  }
+
+  fun endLoop() {
+    internalLoopState = internalLoopState?.enclosing
+  }
+
+  fun createLocal(symbol: Symbol): StubVar {
+    val scope = variables.last()
+    val variable = StubVar(localVarIndex++, symbol)
+    scope.add(variable)
+    return variable
+  }
+
+  fun pushScope() {
+    variables.add(mutableListOf())
+  }
+
+  fun popScope() {
+    variables.removeLast()
+  }
+
+  fun resolve(symbol: Symbol): Loadable {
+    for (scope in variables.reversed()) {
+      val found = scope.firstOrNull { it.symbol == symbol }
+      if (found != null) {
+        return Loadable(stubVar = found)
+      }
+    }
+    val found = this.symbol.compilableSlab.resolve(symbol)
+    if (found != null) {
+      return Loadable(call = found)
+    }
+    throw RuntimeException("Unable to resolve symbol: ${symbol.id}")
+  }
+}

compiler/src/main/kotlin/gay/pizza/pork/compiler/LoopState.kt

@@ -5,7 +5,6 @@ import gay.pizza.pork.bytecode.MutableRel
 class LoopState(
   val startOfLoop: UInt,
   val exitJumpTarget: MutableRel,
-  val body: MutableRel,
-  val scopeDepth: Int,
+  val scopeDepth: UInt,
   val enclosing: LoopState? = null
 )

compiler/src/main/kotlin/gay/pizza/pork/compiler/StubOpEmitter.kt

@@ -3,99 +3,55 @@ package gay.pizza.pork.compiler
 import gay.pizza.pork.ast.FunctionLevelVisitor
 import gay.pizza.pork.ast.gen.*
 import gay.pizza.pork.bytecode.MutableRel
-import gay.pizza.pork.bytecode.Op
 import gay.pizza.pork.bytecode.Opcode
 
 class StubOpEmitter(val compiler: Compiler, val symbol: CompilableSymbol) : FunctionLevelVisitor<Unit>() {
-  private val ops = mutableListOf<StubOp>()
-
-  private var loopState: LoopState? = null
-  private val localVariables = mutableListOf<MutableList<StubVar>>()
-  private var localVarIndex = 0u
-
-  private val requiredLoopState: LoopState
-    get() {
-      if (loopState != null) {
-        return loopState!!
-      }
-      throw RuntimeException("loopState expected but was not found.")
-    }
-
-  private fun allocateLocalVariable(symbol: Symbol): StubVar {
-    val scope = localVariables.last()
-    val variable = StubVar(localVarIndex++, symbol)
-    scope.add(variable)
-    return variable
-  }
-
-  private fun resolveSymbol(symbol: Symbol): CallOrStubVar {
-    for (scope in localVariables.reversed()) {
-      val found = scope.firstOrNull { it.symbol == symbol }
-      if (found != null) {
-        return CallOrStubVar(stubVar = found)
-      }
-    }
-    val found = this.symbol.compilableSlab.compilableSymbolOf(symbol)
-    if (found != null) {
-      return CallOrStubVar(call = found)
-    }
-    throw RuntimeException("Unable to resolve symbol: ${symbol.id}")
-  }
-
-  private fun pushScope() {
-    emit(Opcode.ScopeIn)
-    localVariables.add(mutableListOf())
-  }
-
-  private fun popScope() {
-    emit(Opcode.ScopeOut)
-    localVariables.removeLast()
-  }
-
-  fun enter() {
-    pushScope()
-  }
+  val code = CodeBuilder(symbol)
 
   fun allocateOuterScope(definition: FunctionDefinition) {
     val allNormalArguments = definition.arguments.takeWhile { !it.multiple }
     val varArgument = definition.arguments.firstOrNull { it.multiple }
 
     for (arg in allNormalArguments.reversed()) {
-      val functionLocal = allocateLocalVariable(arg.symbol)
-      emit(Opcode.StoreLocal, listOf(functionLocal.index))
+      val functionLocal = code.localState.createLocal(arg.symbol)
+      code.emit(Opcode.StoreLocal, listOf(functionLocal.index))
     }
 
     if (varArgument != null) {
-      val functionLocal = allocateLocalVariable(varArgument.symbol)
-      emit(Opcode.StoreLocal, listOf(functionLocal.index))
+      val functionLocal = code.localState.createLocal(varArgument.symbol)
+      code.emit(Opcode.StoreLocal, listOf(functionLocal.index))
     }
   }
 
+  fun enter() {
+    code.localState.pushScope()
+  }
+
   fun exit() {
-    popScope()
-    emit(Opcode.Return)
+    code.localState.popScope()
+    code.emit(Opcode.Return)
   }
 
   override fun visitBlock(node: Block) {
-    pushScope()
+    code.localState.pushScope()
     node.visitChildren(this)
-    popScope()
+    code.localState.popScope()
   }
 
   override fun visitBooleanLiteral(node: BooleanLiteral) {
-    emit(if (node.value) Opcode.True else Opcode.False)
+    code.emit(if (node.value) Opcode.True else Opcode.False)
   }
 
   override fun visitBreak(node: Break) {
-    patch(Opcode.Jump, listOf(0u), 0, symbol, requiredLoopState.exitJumpTarget)
+    code.patch(Opcode.Jump, listOf(0u), 0, symbol, code.localState.loopState!!.exitJumpTarget)
   }
 
   override fun visitContinue(node: Continue) {
-    patch(Opcode.Jump, listOf(0u), 0, symbol, requiredLoopState.startOfLoop)
+    code.patch(Opcode.Jump, listOf(0u), 0, symbol, code.localState.loopState!!.startOfLoop)
   }
 
   override fun visitDoubleLiteral(node: DoubleLiteral) {
-    emit(Opcode.Integer, listOf(node.value.toUInt()))
+    code.emit(Opcode.Integer, listOf(node.value.toUInt()))
   }
 
   override fun visitForIn(node: ForIn) {
@@ -108,7 +64,7 @@ class StubOpEmitter(val compiler: Compiler, val symbol: CompilableSymbol) : Func
     val targetSymbol = compiler.resolve(targetScopeSymbol)
     val functionDefinition = targetSymbol.scopeSymbol.definition as FunctionDefinition
     val retRel = MutableRel(0u)
-    patch(Opcode.Integer, listOf(0u), 0, symbol, retRel)
+    code.patch(Opcode.Integer, listOf(0u), 0, symbol, retRel)
 
     val normalArguments = mutableListOf<Expression>()
     var variableArguments: List<Expression>? = null
@@ -127,70 +83,70 @@ class StubOpEmitter(val compiler: Compiler, val symbol: CompilableSymbol) : Func
       for (item in variableArguments.reversed()) {
         item.visit(this)
       }
-      emit(Opcode.List, listOf(variableArguments.size.toUInt()))
+      code.emit(Opcode.List, listOf(variableArguments.size.toUInt()))
     }
 
     for (item in normalArguments.reversed()) {
       visit(item)
     }
 
-    retRel.rel = (ops.size + 1).toUInt()
-    patch(Opcode.Call, listOf(0u), mapOf(0 to targetSymbol))
+    retRel.rel = code.nextOpInst() + 1u
+    code.patch(Opcode.Call, listOf(0u), mapOf(0 to targetSymbol))
   }
 
   override fun visitIf(node: If) {
     val thenRel = MutableRel(0u)
     val endRel = MutableRel(0u)
     node.condition.visit(this)
-    patch(Opcode.JumpIf, listOf(0u), 0, symbol, thenRel)
+    code.patch(Opcode.JumpIf, listOf(0u), 0, symbol, thenRel)
     node.elseBlock?.visit(this)
-    patch(Opcode.Jump, listOf(0u), 0, symbol, endRel)
-    thenRel.rel = ops.size.toUInt()
+    code.patch(Opcode.Jump, listOf(0u), 0, symbol, endRel)
+    thenRel.rel = code.nextOpInst()
     node.thenBlock.visit(this)
-    endRel.rel = ops.size.toUInt()
+    endRel.rel = code.nextOpInst()
   }
 
   override fun visitIndexedBy(node: IndexedBy) {
     node.expression.visit(this)
     node.index.visit(this)
-    emit(Opcode.Index)
+    code.emit(Opcode.Index)
   }
 
   override fun visitInfixOperation(node: InfixOperation) {
     node.left.visit(this)
     node.right.visit(this)
     when (node.op) {
-      InfixOperator.Plus -> emit(Opcode.Add)
-      InfixOperator.Minus -> emit(Opcode.Subtract)
-      InfixOperator.Multiply -> emit(Opcode.Multiply)
-      InfixOperator.Divide -> emit(Opcode.Divide)
-      InfixOperator.Equals -> emit(Opcode.CompareEqual)
+      InfixOperator.Plus -> code.emit(Opcode.Add)
+      InfixOperator.Minus -> code.emit(Opcode.Subtract)
+      InfixOperator.Multiply -> code.emit(Opcode.Multiply)
+      InfixOperator.Divide -> code.emit(Opcode.Divide)
+      InfixOperator.Equals -> code.emit(Opcode.CompareEqual)
       InfixOperator.NotEquals -> {
-        emit(Opcode.CompareEqual)
-        emit(Opcode.Not)
+        code.emit(Opcode.CompareEqual)
+        code.emit(Opcode.Not)
       }
-      InfixOperator.EuclideanModulo -> emit(Opcode.EuclideanModulo)
-      InfixOperator.Remainder -> emit(Opcode.Remainder)
-      InfixOperator.Lesser -> emit(Opcode.CompareLesser)
-      InfixOperator.Greater -> emit(Opcode.CompareGreater)
-      InfixOperator.GreaterEqual -> emit(Opcode.CompareGreaterEqual)
-      InfixOperator.LesserEqual -> emit(Opcode.CompareLesserEqual)
-      InfixOperator.BooleanAnd -> emit(Opcode.And)
-      InfixOperator.BooleanOr -> emit(Opcode.Or)
-      InfixOperator.BinaryAnd -> emit(Opcode.BinaryAnd)
-      InfixOperator.BinaryOr -> emit(Opcode.BinaryOr)
-      InfixOperator.BinaryExclusiveOr -> emit(Opcode.BinaryXor)
+      InfixOperator.EuclideanModulo -> code.emit(Opcode.EuclideanModulo)
+      InfixOperator.Remainder -> code.emit(Opcode.Remainder)
+      InfixOperator.Lesser -> code.emit(Opcode.CompareLesser)
+      InfixOperator.Greater -> code.emit(Opcode.CompareGreater)
+      InfixOperator.GreaterEqual -> code.emit(Opcode.CompareGreaterEqual)
+      InfixOperator.LesserEqual -> code.emit(Opcode.CompareLesserEqual)
+      InfixOperator.BooleanAnd -> code.emit(Opcode.And)
+      InfixOperator.BooleanOr -> code.emit(Opcode.Or)
+      InfixOperator.BinaryAnd -> code.emit(Opcode.BinaryAnd)
+      InfixOperator.BinaryOr -> code.emit(Opcode.BinaryOr)
+      InfixOperator.BinaryExclusiveOr -> code.emit(Opcode.BinaryXor)
     }
   }
 
   override fun visitIntegerLiteral(node: IntegerLiteral) {
-    emit(Opcode.Integer, listOf(node.value.toUInt()))
+    code.emit(Opcode.Integer, listOf(node.value.toUInt()))
   }
 
   override fun visitLetAssignment(node: LetAssignment) {
-    val variable = allocateLocalVariable(node.symbol)
+    val variable = code.localState.createLocal(node.symbol)
     node.value.visit(this)
-    emit(Opcode.StoreLocal, listOf(variable.index))
+    code.emit(Opcode.StoreLocal, listOf(variable.index))
   }
 
   override fun visitListLiteral(node: ListLiteral) {
@@ -198,15 +154,15 @@ class StubOpEmitter(val compiler: Compiler, val symbol: CompilableSymbol) : Func
     for (item in node.items) {
       item.visit(this)
     }
-    emit(Opcode.List, listOf(count.toUInt()))
+    code.emit(Opcode.List, listOf(count.toUInt()))
   }
 
   override fun visitLongLiteral(node: LongLiteral) {
-    emit(Opcode.Integer, listOf(node.value.toUInt()))
+    code.emit(Opcode.Integer, listOf(node.value.toUInt()))
   }
 
   override fun visitNoneLiteral(node: NoneLiteral) {
-    emit(Opcode.None)
+    code.emit(Opcode.None)
   }
 
   override fun visitParentheses(node: Parentheses) {
@@ -216,121 +172,90 @@ class StubOpEmitter(val compiler: Compiler, val symbol: CompilableSymbol) : Func
   override fun visitPrefixOperation(node: PrefixOperation) {
     node.expression.visit(this)
     when (node.op) {
-      PrefixOperator.BooleanNot -> emit(Opcode.Not)
-      PrefixOperator.UnaryPlus -> emit(Opcode.UnaryPlus)
-      PrefixOperator.UnaryMinus -> emit(Opcode.UnaryMinus)
-      PrefixOperator.BinaryNot -> emit(Opcode.BinaryNot)
+      PrefixOperator.BooleanNot -> code.emit(Opcode.Not)
+      PrefixOperator.UnaryPlus -> code.emit(Opcode.UnaryPlus)
+      PrefixOperator.UnaryMinus -> code.emit(Opcode.UnaryMinus)
+      PrefixOperator.BinaryNot -> code.emit(Opcode.BinaryNot)
     }
   }
 
   override fun visitSetAssignment(node: SetAssignment) {
-    val stubVarOrCall = resolveSymbol(node.symbol)
+    val stubVarOrCall = code.localState.resolve(node.symbol)
     if (stubVarOrCall.stubVar == null) {
       throw RuntimeException("Invalid set assignment.")
     }
     node.value.visit(this)
-    emit(Opcode.StoreLocal, listOf(stubVarOrCall.stubVar.index))
+    code.emit(Opcode.StoreLocal, listOf(stubVarOrCall.stubVar.index))
   }
 
   override fun visitStringLiteral(node: StringLiteral) {
     val bytes = node.text.toByteArray()
     val constant = compiler.constantPool.assign(bytes)
-    emit(Opcode.Constant, listOf(constant))
+    code.emit(Opcode.Constant, listOf(constant))
   }
 
   override fun visitSuffixOperation(node: SuffixOperation) {
-    val stubVarOrCall = resolveSymbol(node.reference.symbol)
+    val stubVarOrCall = code.localState.resolve(node.reference.symbol)
     if (stubVarOrCall.stubVar == null) {
       throw RuntimeException("Invalid suffix operation.")
     }
     load(stubVarOrCall)
     when (node.op) {
       SuffixOperator.Increment -> {
-        emit(Opcode.Integer, listOf(1u))
-        emit(Opcode.Add, emptyList())
-        emit(Opcode.StoreLocal, listOf(stubVarOrCall.stubVar.index))
+        code.emit(Opcode.Integer, listOf(1u))
+        code.emit(Opcode.Add, emptyList())
+        code.emit(Opcode.StoreLocal, listOf(stubVarOrCall.stubVar.index))
       }
       SuffixOperator.Decrement -> {
-        emit(Opcode.Integer, listOf(1u))
-        emit(Opcode.Subtract, emptyList())
-        emit(Opcode.StoreLocal, listOf(stubVarOrCall.stubVar.index))
+        code.emit(Opcode.Integer, listOf(1u))
+        code.emit(Opcode.Subtract, emptyList())
+        code.emit(Opcode.StoreLocal, listOf(stubVarOrCall.stubVar.index))
       }
     }
   }
 
   override fun visitSymbolReference(node: SymbolReference) {
-    val variable = resolveSymbol(node.symbol)
+    val variable = code.localState.resolve(node.symbol)
     load(variable)
   }
 
   override fun visitVarAssignment(node: VarAssignment) {
-    val variable = allocateLocalVariable(node.symbol)
+    val variable = code.localState.createLocal(node.symbol)
     node.value.visit(this)
-    emit(Opcode.StoreLocal, listOf(variable.index))
+    code.emit(Opcode.StoreLocal, listOf(variable.index))
   }
 
   override fun visitWhile(node: While) {
     val startOfBody = MutableRel(0u)
+    val startOfLoop = MutableRel(0u)
     val endOfLoop = MutableRel(0u)
-    val currentLoopState = LoopState(
-      startOfLoop = ops.size.toUInt(),
-      exitJumpTarget = endOfLoop,
-      body = startOfBody,
-      scopeDepth = (loopState?.scopeDepth ?: 0) + 1,
-      enclosing = loopState
-    )
-    loopState = currentLoopState
+    code.localState.startLoop(code.nextOpInst(), endOfLoop)
+    startOfLoop.rel = code.nextOpInst()
     node.condition.visit(this)
-    patch(Opcode.JumpIf, listOf(0u), 0, symbol, startOfBody)
-    patch(Opcode.Jump, listOf(0u), 0, symbol, endOfLoop)
-    startOfBody.rel = ops.size.toUInt()
+    code.patch(Opcode.JumpIf, listOf(0u), 0, symbol, startOfBody)
+    code.patch(Opcode.Jump, listOf(0u), 0, symbol, endOfLoop)
+    startOfBody.rel = code.nextOpInst()
     node.block.visit(this)
-    patch(Opcode.Jump, listOf(0u), 0, symbol, currentLoopState.startOfLoop)
-    endOfLoop.rel = ops.size.toUInt()
+    code.patch(Opcode.Jump, listOf(0u), 0, symbol, startOfLoop)
+    endOfLoop.rel = code.nextOpInst()
+    code.localState.endLoop()
   }
 
   override fun visitNativeFunctionDescriptor(node: NativeFunctionDescriptor) {
     for (def in node.definitions) {
       val defConstant = compiler.constantPool.assign(def.text.toByteArray())
-      emit(Opcode.Constant, listOf(defConstant))
+      code.emit(Opcode.Constant, listOf(defConstant))
     }
     val formConstant = compiler.constantPool.assign(node.form.id.toByteArray())
-    emit(Opcode.Native, listOf(formConstant, node.definitions.size.toUInt()))
+    code.emit(Opcode.Native, listOf(formConstant, node.definitions.size.toUInt()))
   }
 
-  private fun emit(code: Opcode) {
-    emit(code, emptyList())
-  }
-
-  private fun emit(code: Opcode, arguments: List<UInt>) {
-    ops.add(StaticOp(Op(code, arguments)))
-  }
-
-  private fun patch(code: Opcode, arguments: List<UInt>, index: Int, symbol: CompilableSymbol, rel: MutableRel) {
-    ops.add(PatchRelOp(Op(code, arguments), index, symbol, rel))
-  }
-
-  private fun patch(code: Opcode, arguments: List<UInt>, index: Int, symbol: CompilableSymbol, rel: UInt) {
-    ops.add(PatchRelOp(Op(code, arguments), index, symbol, MutableRel(rel)))
-  }
-
-  private fun patch(code: Opcode, arguments: List<UInt>, patches: Map<Int, CompilableSymbol>) {
-    ops.add(PatchSymOp(Op(code, arguments), patches))
-  }
-
-  fun ops(): List<StubOp> = ops
-
-  private fun load(callOrStubVar: CallOrStubVar) {
+  private fun load(callOrStubVar: Loadable) {
     if (callOrStubVar.stubVar != null) {
-      emit(Opcode.LoadLocal, listOf(callOrStubVar.stubVar.index))
+      code.emit(Opcode.LoadLocal, listOf(callOrStubVar.stubVar.index))
     } else {
-      emit(Opcode.Integer, listOf(ops.size.toUInt() + 2u))
-      patch(Opcode.Call, listOf(0u), mapOf(0 to callOrStubVar.call!!))
+      code.emit(Opcode.Integer, listOf(code.nextOpInst() + 2u))
+      code.patch(Opcode.Call, listOf(0u), mapOf(0 to callOrStubVar.call!!))
     }
   }
-
-  private class CallOrStubVar(
-    val call: CompilableSymbol? = null,
-    val stubVar: StubVar? = null
-  )
 }

tool/src/main/kotlin/gay/pizza/pork/tool/CompileCommand.kt

@@ -17,7 +17,7 @@ class CompileCommand : CliktCommand(help = "Compile Pork to Bytecode", name = "c
     val compiler = Compiler()
     val slab = world.load(tool.rootImportLocator)
     val compiledSlab = compiler.compilableSlabs.of(slab)
-    val compiledMain = compiledSlab.compilableSymbolOf(Symbol("main"))
+    val compiledMain = compiledSlab.resolve(Symbol("main"))
       ?: throw RuntimeException("'main' function not found.")
     val compiledWorld = compiler.compile(compiledMain)
     for (symbol in compiledWorld.symbolTable.symbols) {

vm/src/main/kotlin/gay/pizza/pork/vm/VirtualMachineProvider.kt

@@ -12,7 +12,7 @@ class VirtualMachineProvider(val world: World) : ExecutionContextProvider {
     val compiler = Compiler()
     val slab = world.load(importLocator)
     val compilableSlab = compiler.compilableSlabs.of(slab)
-    val compilableSymbol = compilableSlab.compilableSymbolOf(entryPointSymbol) ?:
+    val compilableSymbol = compilableSlab.resolve(entryPointSymbol) ?:
       throw RuntimeException("Unable to find compilable symbol for entry point '${entryPointSymbol.id}'")
     val compiledWorld = compiler.compile(compilableSymbol)
     return VirtualMachine(compiledWorld)