mirror of https://github.com/japl-lang/japl.git
722 lines
29 KiB
Nim
722 lines
29 KiB
Nim
# Copyright 2020 Mattia Giambirtone
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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## A stack-based bytecode virtual machine implementation.
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## This is the entire runtime environment for JAPL
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{.experimental: "implicitDeref".}
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import algorithm
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import strformat
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import config
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import compiler
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import tables
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import meta/opcode
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import meta/frame
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import types/baseObject
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import types/japlString
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import types/japlNil
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import types/exception
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import types/numbers
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import types/boolean
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import types/methods
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import types/function
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import types/native
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import memory
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import tables
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when DEBUG_TRACE_VM:
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import util/debug
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type
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KeyboardInterrupt* = object of CatchableError
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## Custom exception to handle Ctrl+C
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InterpretResult = enum
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## All possible interpretation results
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Ok,
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CompileError,
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RuntimeError
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VM* = ref object
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## A wrapper around the virtual machine
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## functionality
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lastPop*: ptr Obj
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frameCount*: int
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source*: string
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frames*: seq[CallFrame]
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stack*: ref seq[ptr Obj]
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stackTop*: int
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objects*: seq[ptr Obj]
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globals*: Table[string, ptr Obj]
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cached: array[5, ptr Obj]
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file*: string
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func handleInterrupt() {.noconv.} =
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## Raises an appropriate exception
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## to let us catch and handle
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## Ctrl+C gracefully
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raise newException(KeyboardInterrupt, "Ctrl+C")
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proc resetStack*(self: var VM) =
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## Resets the VM stack to a blank state
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self.stack = new(seq[ptr Obj])
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self.frames = @[]
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self.frameCount = 0
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self.stackTop = 0
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proc getBoolean(self: var VM, kind: bool): ptr Obj =
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## Tiny little optimization for booleans
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## which are pre-allocated on startup
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if kind:
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return self.cached[0]
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else:
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return self.cached[1]
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proc error*(self: var VM, error: ptr JAPLException) =
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## Reports runtime errors with a nice traceback
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# TODO: Exceptions
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var previous = "" # All this stuff seems overkill, but it makes the traceback look nicer
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var repCount = 0 # and if we are here we are far beyond a point where performance matters
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var mainReached = false
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var output = ""
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stderr.write("Traceback (most recent call last):\n")
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for frame in reversed(self.frames):
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if mainReached:
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break
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var function = frame.function
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var line = function.chunk.lines[frame.ip]
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if function.name == nil:
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output = &" File '{self.file}', line {line}, in '<module>':"
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mainReached = true
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else:
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output = &" File '{self.file}', line {line}, in {stringify(function.name)}():"
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if output != previous:
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if repCount > 0:
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stderr.write(&" ...previous line repeated {repCount} more times...\n")
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repCount = 0
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previous = output
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stderr.write(&"{output}\n")
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else:
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repCount += 1
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stderr.write(error.stringify())
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stderr.write("\n")
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self.resetStack()
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proc pop*(self: var VM): ptr Obj =
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## Pops an object off the stack
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result = self.stack.pop()
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self.stackTop -= 1
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proc push*(self: var VM, obj: ptr Obj) =
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## Pushes an object onto the stack
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self.stack.add(obj)
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if obj notin self.objects and obj notin self.cached:
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self.objects.add(obj)
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self.stackTop += 1
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proc peek*(self: var VM, distance: int): ptr Obj =
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## Peeks an object (at a given distance from the
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## current index) from the stack
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return self.stack[self.stackTop - distance - 1]
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template addObject*(self: var VM, obj: ptr Obj): untyped =
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## Stores an object in the VM's internal
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## list of objects in order to reclaim
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## its memory later
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let temp = obj
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self.objects.add(temp)
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temp
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# TODO: Move this to jobject.nim
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proc slice(self: var VM): bool =
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## Handles single-operator slice expressions
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## (consider moving this to an appropriate
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## slice method)
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var idx = self.pop()
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var peeked = self.pop()
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case peeked.kind:
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of ObjectType.String:
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var str = peeked.toStr()
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if not idx.isInt():
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self.error(newTypeError("string indeces must be integers"))
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return false
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else:
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var index: int = idx.toInt()
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if index < 0:
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index = len(str) + idx.toInt()
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if index < 0: # If even now it is less than 0 than it is out of bounds
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self.error(newIndexError("string index out of bounds"))
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return false
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elif index - 1 > len(str) - 1:
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self.error(newIndexError("string index out of bounds"))
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return false
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else:
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self.push(asStr(&"{str[index]}"))
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return true
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else:
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self.error(newTypeError(&"unsupported slicing for object of type '{peeked.typeName()}'"))
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return false
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# TODO: Move this to types/
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proc sliceRange(self: var VM): bool =
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## Handles slices when there's both a start
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## and an end index (even implicit ones)
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var sliceEnd = self.pop()
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var sliceStart = self.pop()
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var popped = self.pop()
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case popped.kind:
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of ObjectType.String:
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var str = popped.toStr()
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if sliceEnd.isNil():
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sliceEnd = len(str).asInt()
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if sliceStart.isNil():
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sliceStart = asInt(0)
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elif not sliceStart.isInt() or not sliceEnd.isInt():
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self.error(newTypeError("string indexes must be integers"))
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return false
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else:
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var startIndex = sliceStart.toInt()
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var endIndex = sliceEnd.toInt()
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if startIndex < 0:
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sliceStart = (len(str) + sliceStart.toInt()).asInt()
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if startIndex < 0:
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sliceStart = (len(str) + sliceEnd.toInt()).asInt()
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elif startIndex - 1 > len(str) - 1:
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self.push(asStr(""))
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return true
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if endIndex - 1 > len(str) - 1:
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sliceEnd = len(str).asInt()
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if startIndex > endIndex:
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self.push(asStr(""))
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return true
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self.push(asStr(str[sliceStart.toInt()..<sliceEnd.toInt()]))
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return true
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else:
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self.error(newTypeError(&"unsupported slicing for object of type '{popped.typeName()}'"))
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return false
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proc call(self: var VM, function: ptr Function, argCount: int): bool =
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## Sets up the call frame and performs error checking
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## when calling callables
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if argCount != function.arity:
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self.error(newTypeError(&"function '{stringify(function.name)}' takes {function.arity} argument(s), got {argCount}"))
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return false
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if self.frameCount == FRAMES_MAX:
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self.error(newRecursionError("max recursion depth exceeded"))
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return false
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let slot = self.stack.high() - argCount
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var frame = CallFrame(function: function, ip: 0, slot: slot, stack: self.stack) # TODO:
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# Check why this raises NilAccessError when high recursion limit is hit
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self.frames.add(frame)
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self.frameCount += 1
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return true
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proc call(self: var VM, native: ptr Native, argCount: int): bool =
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if argCount != native.arity and native.arity != -1:
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self.error(newTypeError(&"function '{stringify(native.name)}' takes {native.arity} argument(s), got {argCount}"))
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return false
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let slot = self.stack.high() - argCount + 1
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var args: seq[ptr Obj]
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for i in countup(slot, self.stack.high()):
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args.add(self.stack[i])
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let nativeResult = native.nimproc(args)
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if not nativeResult.ok:
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self.error(cast[ptr JaplException](nativeResult.result))
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# assumes that all native procs behave well, and if not ok, they
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# only return japl exceptions
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for i in countup(slot - 1, self.stack.high()):
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discard self.pop() # TODO once stack is a custom datatype,
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# just reduce its length
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self.push(nativeResult.result)
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return true
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proc callObject(self: var VM, callee: ptr Obj, argCount: uint8): bool =
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## Wrapper around call() to do type checking
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if callee.isCallable():
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case callee.kind:
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of ObjectType.Function:
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return self.call(cast[ptr Function](callee), int(argCount))
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of ObjectType.Native:
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return self.call(cast[ptr Native](callee), int(argCount))
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else: # TODO: Classes
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discard # Unreachable
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else:
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self.error(newTypeError(&"object of type '{callee.typeName()}' is not callable"))
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return false
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proc defineGlobal*(self: VM, name: string, value: ptr Obj) =
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self.globals[name] = value
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proc readByte(self: CallFrame): uint8 =
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## Reads a single byte from the given
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## frame's chunk of bytecode
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inc(self.ip)
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result = self.function.chunk.code[self.ip - 1]
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proc readBytes(self: CallFrame): int =
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## Reads and decodes 3 bytes from the
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## given frame's chunk into an integer
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var arr = [self.readByte(), self.readByte(), self.readByte()]
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copyMem(result.addr, unsafeAddr(arr), sizeof(arr))
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proc readShort(self: CallFrame): uint16 =
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## Reads a 16 bit number from the
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## given frame's chunk
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let arr = [self.readByte(), self.readByte()]
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copyMem(result.addr, unsafeAddr(arr), sizeof(uint16))
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proc readConstant(self: CallFrame): ptr Obj =
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## Reads a constant from the given
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## frame's constant table
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result = self.function.chunk.consts[uint8 self.readByte()]
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proc readLongConstant(self: CallFrame): ptr Obj =
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## Reads a long constant from the
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## given frame's constant table
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var arr = [self.readByte(), self.readByte(), self.readByte()]
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var idx: int
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copyMem(idx.addr, unsafeAddr(arr), sizeof(arr))
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result = self.function.chunk.consts[idx]
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proc run(self: var VM, repl: bool): InterpretResult =
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## Chews trough bytecode instructions executing
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## them one at a time: this is the runtime's
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## main loop
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var frame = self.frames[self.frameCount - 1]
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var instruction: uint8
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var opcode: OpCode
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var stackOffset: int = 2
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while true:
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{.computedgoto.} # See https://nim-lang.org/docs/manual.html#pragmas-computedgoto-pragma
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instruction = frame.readByte()
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opcode = OpCode(instruction)
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## This offset dictates how the call frame behaves when converting
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## relative frame indexes to absolute stack indexes, since the behavior
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## in function local vs. global/scope-local scope is different
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if frame.function.name == nil:
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stackOffset = 2
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else:
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stackOffset = 1
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when DEBUG_TRACE_VM: # Insight inside the VM
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stdout.write("Current VM stack status: [")
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for v in self.stack:
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stdout.write(stringify(v))
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stdout.write(", ")
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stdout.write("]\n")
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stdout.write("Current global scope status: {")
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for k, v in self.globals.pairs():
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stdout.write(k)
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stdout.write(": ")
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stdout.write(stringify(v))
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stdout.write("}\n")
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stdout.write("Current frame type:")
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if frame.function.name == nil:
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stdout.write(" main\n")
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else:
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stdout.write(&" function, '{frame.function.name.stringify()}'\n")
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stdout.write(&"Current frame count: {self.frameCount}\n")
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stdout.write("Current frame stack status: ")
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stdout.write("[")
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for e in frame.getView():
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stdout.write(stringify(e))
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stdout.write(", ")
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stdout.write("]\n")
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discard disassembleInstruction(frame.function.chunk, frame.ip - 1)
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case opcode: # Main OpCodes dispatcher
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of OpCode.Constant:
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self.push(frame.readConstant())
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of OpCode.ConstantLong:
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self.push(frame.readLongConstant())
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of OpCode.Negate:
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let operand = self.pop()
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try:
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self.push(operand.negate())
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except NotImplementedError:
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self.error(newTypeError(&"unsupported unary operator '-' for object of type '{operand.typeName()}'"))
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return RuntimeError
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of OpCode.Shl: # Bitwise left-shift
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var right = self.pop()
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var left = self.pop()
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try:
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self.push(left.binaryShl(right))
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except NotImplementedError:
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self.error(newTypeError(&"unsupported binary operator '<<' for objects of type '{left.typeName()}' and '{right.typeName()}'"))
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return RuntimeError
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of OpCode.Shr: # Bitwise right-shift
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var right = self.pop()
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var left = self.pop()
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try:
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self.push(left.binaryShr(right))
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except NotImplementedError:
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self.error(newTypeError(&"unsupported binary operator '>>' for objects of type '{left.typeName()}' and '{right.typeName()}'"))
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return RuntimeError
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of OpCode.Xor: # Bitwise xor
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var right = self.pop()
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var left = self.pop()
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try:
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self.push(left.binaryXor(right))
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except NotImplementedError:
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self.error(newTypeError(&"unsupported binary operator '^' for objects of type '{left.typeName()}' and '{right.typeName()}'"))
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return RuntimeError
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of OpCode.Bor: # Bitwise or
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var right = self.pop()
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var left = self.pop()
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try:
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self.push(left.binaryOr(right))
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except NotImplementedError:
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self.error(newTypeError(&"unsupported binary operator '&' for objects of type '{left.typeName()}' and '{right.typeName()}'"))
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return RuntimeError
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of OpCode.Bnot: # Bitwise not
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var operand = self.pop()
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try:
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self.push(operand.binaryNot())
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except NotImplementedError:
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self.error(newTypeError(&"unsupported unary operator '~' for object of type '{operand.typeName()}'"))
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return RuntimeError
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of OpCode.Band: # Bitwise and
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var right = self.pop()
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var left = self.pop()
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try:
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self.push(left.binaryAnd(right))
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except NotImplementedError:
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self.error(newTypeError(&"unsupported binary operator '&' for objects of type '{left.typeName()}' and '{right.typeName()}'"))
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return RuntimeError
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of OpCode.Add:
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var right = self.pop()
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var left = self.pop()
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try:
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self.push(left.sum(right))
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except NotImplementedError:
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self.error(newTypeError(&"unsupported binary operator '+' for objects of type '{left.typeName()}' and '{right.typeName()}'"))
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return RuntimeError
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of OpCode.Subtract:
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var right = self.pop()
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var left = self.pop()
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try:
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self.push(left.sub(right))
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except NotImplementedError:
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self.error(newTypeError(&"unsupported binary operator '-' for objects of type '{left.typeName()}' and '{right.typeName()}'"))
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return RuntimeError
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of OpCode.Divide:
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var right = self.pop()
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var left = self.pop()
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try:
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self.push(left.trueDiv(right))
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except NotImplementedError:
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self.error(newTypeError(&"unsupported binary operator '/' for objects of type '{left.typeName()}' and '{right.typeName()}'"))
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return RuntimeError
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of OpCode.Multiply:
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var right = self.pop()
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var left = self.pop()
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try:
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self.push(left.mul(right))
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except NotImplementedError:
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self.error(newTypeError(&"unsupported binary operator '*' for objects of type '{left.typeName()}' and '{right.typeName()}'"))
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return RuntimeError
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of OpCode.Mod:
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var right = self.pop()
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var left = self.pop()
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try:
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self.push(left.divMod(right))
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except NotImplementedError:
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self.error(newTypeError(&"unsupported binary operator '%' for objects of type '{left.typeName()}' and '{right.typeName()}'"))
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return RuntimeError
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of OpCode.Pow:
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var right = self.pop()
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var left = self.pop()
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try:
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self.push(left.pow(right))
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except NotImplementedError:
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self.error(newTypeError(&"unsupported binary operator '**' for objects of type '{left.typeName()}' and '{right.typeName()}'"))
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return RuntimeError
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of OpCode.True:
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## TODO: Make sure that even operations that can yield
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## preallocated types, but do not have access to the VM,
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## yield these cached types
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self.push(cast[ptr Bool](self.getBoolean(true)))
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of OpCode.False:
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self.push(cast[ptr Bool](self.getBoolean(false)))
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of OpCode.Nil:
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self.push(cast[ptr Nil](self.cached[2]))
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of OpCode.Nan:
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self.push(cast[ptr NotANumber](self.cached[4]))
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of OpCode.Inf:
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self.push(cast[ptr Infinity](self.cached[3]))
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of OpCode.Not:
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self.push(self.pop().isFalsey().asBool())
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of OpCode.Equal:
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# Here order doesn't matter, because if a == b
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# then b == a (at least in *most* languages, sigh)
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self.push(self.getBoolean(self.pop().eq(self.pop())))
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# Doesn't this chain of calls look beautifully
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# intuitive?
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of OpCode.Less:
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var right = self.pop()
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var left = self.pop()
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try:
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self.push(self.getBoolean(left.lt(right)))
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except NotImplementedError:
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self.error(newTypeError(&"unsupported binary operator '<' for objects of type '{left.typeName()}' and '{right.typeName()}'"))
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return RuntimeError
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of OpCode.Greater:
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var right = self.pop()
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var left = self.pop()
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try:
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self.push(self.getBoolean(left.gt(right)))
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except NotImplementedError:
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self.error(newTypeError(&"unsupported binary operator '>' for objects of type '{left.typeName()}' and '{right.typeName()}'"))
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return RuntimeError
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of OpCode.GetItem:
|
|
# TODO: More generic method
|
|
if not self.slice():
|
|
return RuntimeError
|
|
of OpCode.Slice:
|
|
if not self.sliceRange():
|
|
return RuntimeError
|
|
of OpCode.DefineGlobal:
|
|
if frame.function.chunk.consts.len > 255:
|
|
self.globals[frame.readLongConstant().toStr()] = self.peek(0)
|
|
else:
|
|
self.globals[frame.readConstant().toStr()] = self.peek(0)
|
|
discard self.pop()
|
|
of OpCode.GetGlobal:
|
|
if frame.function.chunk.consts.len > 255:
|
|
var constant = frame.readLongConstant().toStr()
|
|
if constant notin self.globals:
|
|
self.error(newReferenceError(&"undefined name '{constant}'"))
|
|
return RuntimeError
|
|
else:
|
|
self.push(self.globals[constant])
|
|
else:
|
|
var constant = frame.readConstant().toStr()
|
|
if constant notin self.globals:
|
|
self.error(newReferenceError(&"undefined name '{constant}'"))
|
|
return RuntimeError
|
|
else:
|
|
self.push(self.globals[constant])
|
|
of OpCode.SetGlobal:
|
|
if frame.function.chunk.consts.len > 255:
|
|
var constant = frame.readLongConstant().toStr()
|
|
if constant notin self.globals:
|
|
self.error(newReferenceError(&"assignment to undeclared name '{constant}'"))
|
|
return RuntimeError
|
|
else:
|
|
self.globals[constant] = self.peek(0)
|
|
else:
|
|
var constant = frame.readConstant().toStr()
|
|
if constant notin self.globals:
|
|
self.error(newReferenceError(&"assignment to undeclared name '{constant}'"))
|
|
return RuntimeError
|
|
else:
|
|
self.globals[constant] = self.peek(0)
|
|
of OpCode.DeleteGlobal:
|
|
# TODO: Inspect potential issues with the GC
|
|
if frame.function.chunk.consts.len > 255:
|
|
var constant = frame.readLongConstant().toStr()
|
|
if constant notin self.globals:
|
|
self.error(newReferenceError(&"undefined name '{constant}'"))
|
|
return RuntimeError
|
|
else:
|
|
self.globals.del(constant)
|
|
else:
|
|
var constant = frame.readConstant().toStr()
|
|
if constant notin self.globals:
|
|
self.error(newReferenceError(&"undefined name '{constant}'"))
|
|
return RuntimeError
|
|
else:
|
|
self.globals.del(constant)
|
|
of OpCode.GetLocal:
|
|
if frame.len > 255:
|
|
self.push(frame[frame.readBytes(), stackOffset])
|
|
else:
|
|
self.push(frame[int frame.readByte(), stackOffset])
|
|
of OpCode.SetLocal:
|
|
if frame.len > 255:
|
|
frame[frame.readBytes(), stackOffset] = self.peek(0)
|
|
else:
|
|
frame[int frame.readByte(), stackOffset] = self.peek(0)
|
|
of OpCode.DeleteLocal:
|
|
# TODO: Inspect potential issues with the GC
|
|
if frame.len > 255:
|
|
var slot = frame.readBytes()
|
|
frame.delete(slot, stackOffset)
|
|
else:
|
|
var slot = frame.readByte()
|
|
frame.delete(int slot, stackOffset)
|
|
of OpCode.Pop:
|
|
self.lastPop = self.pop()
|
|
of OpCode.JumpIfFalse:
|
|
let jmpOffset = int frame.readShort()
|
|
if isFalsey(self.peek(0)):
|
|
frame.ip += int jmpOffset
|
|
of OpCode.Jump:
|
|
frame.ip += int frame.readShort()
|
|
of OpCode.Loop:
|
|
frame.ip -= int frame.readShort()
|
|
of OpCode.Call:
|
|
var argCount = frame.readByte()
|
|
if not self.callObject(self.peek(int argCount), argCount):
|
|
return RuntimeError
|
|
frame = self.frames[self.frameCount - 1]
|
|
of OpCode.Break:
|
|
discard
|
|
of OpCode.Return:
|
|
var retResult = self.pop()
|
|
if repl and not self.lastPop.isNil() and self.frameCount == 1:
|
|
# This avoids unwanted output with recursive calls
|
|
echo stringify(self.lastPop)
|
|
self.lastPop = cast[ptr Nil](self.cached[2])
|
|
self.frameCount -= 1
|
|
discard self.frames.pop()
|
|
if self.frameCount == 0:
|
|
discard self.pop()
|
|
return OK
|
|
|
|
self.stackTop -= frame.clear()
|
|
# frame.clear() clears the stack and returns the amount cleared
|
|
|
|
self.push(retResult)
|
|
# self.stackTop = len(frame.getView()) - 1 # TODO
|
|
|
|
frame = self.frames[self.frameCount - 1]
|
|
|
|
|
|
proc freeObject(self: VM, obj: ptr Obj) =
|
|
## Frees the associated memory
|
|
## of an object
|
|
case obj.kind:
|
|
of ObjectType.String:
|
|
var str = cast[ptr String](obj)
|
|
when DEBUG_TRACE_ALLOCATION:
|
|
echo &"DEBUG - VM: Freeing string object of length {str.len}"
|
|
discard freeArray(char, str.str, str.len)
|
|
discard free(ObjectType.String, obj)
|
|
of ObjectType.Exception, ObjectType.Class,
|
|
ObjectType.Module, ObjectType.BaseObject, ObjectType.Integer,
|
|
ObjectType.Float, ObjectType.Bool, ObjectType.NotANumber,
|
|
ObjectType.Infinity, ObjectType.Nil, ObjectType.Native:
|
|
when DEBUG_TRACE_ALLOCATION:
|
|
if obj notin self.cached:
|
|
echo &"DEBUG- VM: Freeing {obj.typeName()} object with value '{stringify(obj)}'"
|
|
else:
|
|
echo &"DEBUG - VM: Freeing cached {obj.typeName()} object with value '{stringify(obj)}'"
|
|
discard free(obj.kind, obj)
|
|
of ObjectType.Function:
|
|
var fun = cast[ptr Function](obj)
|
|
when DEBUG_TRACE_ALLOCATION:
|
|
if fun.name == nil:
|
|
echo &"DEBUG - VM: Freeing global code object"
|
|
else:
|
|
echo &"DEBUG - VM: Freeing function object with name '{stringify(fun)}'"
|
|
fun.chunk.freeChunk()
|
|
discard free(ObjectType.Function, fun)
|
|
|
|
|
|
proc freeObjects(self: var VM) =
|
|
## Frees all the allocated objects
|
|
## from the VM
|
|
var runtimeObjCount = len(self.objects)
|
|
var cacheCount = len(self.cached)
|
|
var runtimeFreed = 0
|
|
var cachedFreed = 0
|
|
for obj in reversed(self.objects):
|
|
self.freeObject(obj)
|
|
discard self.objects.pop()
|
|
runtimeFreed += 1
|
|
for cached_obj in self.cached:
|
|
self.freeObject(cached_obj)
|
|
cachedFreed += 1
|
|
when DEBUG_TRACE_ALLOCATION:
|
|
echo &"DEBUG - VM: Freed {runtimeFreed + cachedFreed} objects out of {runtimeObjCount + cacheCount} ({cachedFreed}/{cacheCount} cached objects, {runtimeFreed}/{runtimeObjCount} runtime objects)"
|
|
|
|
|
|
proc freeVM*(self: var VM) =
|
|
## Tears down the VM
|
|
unsetControlCHook()
|
|
try:
|
|
self.freeObjects()
|
|
except NilAccessError:
|
|
stderr.write("A fatal error occurred -> could not free memory, segmentation fault\n")
|
|
quit(71)
|
|
when DEBUG_TRACE_ALLOCATION:
|
|
if self.objects.len > 0:
|
|
echo &"DEBUG - VM: Warning, {self.objects.len} objects were not freed"
|
|
|
|
|
|
proc initCache(self: var VM) =
|
|
## Initializes the static cache for singletons
|
|
## such as nil, true, false and nan
|
|
self.cached =
|
|
[
|
|
true.asBool().asObj(),
|
|
false.asBool().asObj(),
|
|
asNil().asObj(),
|
|
asInf().asObj(),
|
|
asNan().asObj()
|
|
]
|
|
|
|
|
|
proc initVM*(): VM =
|
|
## Initializes the VM
|
|
setControlCHook(handleInterrupt)
|
|
var globals: Table[string, ptr Obj] = initTable[string, ptr Obj]()
|
|
result = VM(lastPop: asNil(), objects: @[], globals: globals, source: "", file: "")
|
|
result.initCache()
|
|
|
|
|
|
proc interpret*(self: var VM, source: string, repl: bool = false, file: string): InterpretResult =
|
|
## Interprets a source string containing JAPL code
|
|
self.resetStack()
|
|
self.source = source
|
|
self.file = file
|
|
var compiler = initCompiler(SCRIPT, file=file)
|
|
var compiled = compiler.compile(source)
|
|
# Here we take into account that self.interpret() might
|
|
# get called multiple times and we don't wanna loose
|
|
# what we allocated before, so we merge everything we
|
|
# allocated + everything the compiler allocated at compile time
|
|
self.objects = self.objects & compiler.objects # TODO:
|
|
# revisit the best way to transfer marked objects from the compiler
|
|
# to the vm
|
|
if compiled == nil:
|
|
compiler.freeCompiler()
|
|
return CompileError
|
|
self.push(compiled)
|
|
discard self.callObject(compiled, 0)
|
|
when DEBUG_TRACE_VM:
|
|
echo "==== VM debugger starts ====\n"
|
|
try:
|
|
result = self.run(repl)
|
|
except KeyboardInterrupt:
|
|
self.error(newInterruptedError(""))
|
|
return RuntimeError
|
|
when DEBUG_TRACE_VM:
|
|
echo "==== VM debugger ends ====\n"
|