Refactor to make Opcode the base class

projects/shoggoth/src/python/ichor/assembler.py

@@ -3,33 +3,42 @@
 from dataclasses import dataclass
 from random import choices
 from string import ascii_lowercase, digits
-from typing import List
+from typing import Generator, List, Union, Optional, Sequence
 
-from ichor.isa import Opcode
+from ichor import isa
 
 
-@dataclass
+def gensym(prefix = None) -> isa.Label:
-class Label(object):
+    frag = ''.join(choices(ascii_lowercase + digits, k=8))
-    name: str
+    return isa.Label(f"{prefix or 'gensym'}_{frag}")
 
-    def __hash__(self):
-        return hash(self.name)
 
 class FuncBuilder(object):
     def __init__(self) -> None:
         self._opcodes = []
 
-    def write(self, op: Opcode):
+    def _write(self, op):
         self._opcodes.append(op)
 
-    def make_label(self, prefix=""):
+    def write(self, op: Union[isa.Opcode, isa.Label, Sequence[isa.Opcode]]):
-        frag = ''.join(choices(ascii_lowercase + digits, k=8))
-        return Label(f"{prefix or 'gensym'}_{frag}")
 
-    def set_label(self, label: Label):
+        def flatten(o):
-        self._opcodes.append(label)
+            for e in o:
+                if isinstance(e, (isa.Opcode, isa.Label)):
+                    yield e
+                else:
+                    yield from flatten(e)
 
-    def build(self) -> List[Opcode]:
+        if isinstance(op, (isa.Opcode, isa.Label)):
+            self._opcodes.append(op)
+        else:
+            for e in op:
+                self.write(e)
+
+    def make_label(self, prefix: Optional[str] = ""):
+        return gensym(prefix)
+
+    def build(self) -> List[isa.Opcode]:
         """Assemble the written body into fully resolved opcodes."""
 
         # The trivial two-pass assembler. First pass removes labels from the
@@ -39,8 +48,8 @@ class FuncBuilder(object):
         unassembled = []
         for op in self._opcodes:
             match op:
-                case Label(_) as l:
+                case isa.Label(_) as l:
-                    assert l not in labels  # Label marks must be unique.
+                    assert l not in labels  # isa.Label marks must be unique.
                     labels[l] = len(unassembled)
                 case o:
                     unassembled.append(o)
@@ -50,13 +59,36 @@ class FuncBuilder(object):
         assembled = []
         for op in unassembled:
             match op:
-                case Opcode.GOTO(Label(_) as l):
+                case isa.GOTO(isa.Label(_) as l):
-                    assembled.append(Opcode.GOTO(labels[l]))
+                    assembled.append(isa.GOTO(labels[l]))
 
-                case Opcode.VTEST(Label(_) as l):
+                case isa.VTEST(isa.Label(_) as l):
-                    assembled.append(Opcode.VTEST(labels[l]))
+                    assembled.append(isa.VTEST(labels[l]))
 
                 case o:
                     assembled.append(o)
 
         return assembled
+
+
+def assemble(builder_cls=FuncBuilder, /, **opcodes: List[isa.Opcode]) -> List[isa.Opcode]:
+    builder = builder_cls()
+    for o in opcodes:
+        builder.write(o)
+    return builder.build()
+
+
+class LocalBuilder(FuncBuilder):
+    def __init__(self):
+        super().__init__()
+        self._stack = 0
+        self._labels = {}
+
+    def _write(self, op):
+        pass
+
+    def write_local(self, label: isa.Label):
+        pass
+
+    def get_local(self, label: isa.Label):
+        pass

projects/shoggoth/src/python/ichor/bootstrap.py

@@ -4,7 +4,7 @@ Some utterly trivial functions and types that allow me to begin testing the VM.
 Hopefully no "real" interpreter ever uses this code, since it's obviously replaceable.
 """
 
-from ichor.isa import Opcode
+from ichor import isa
 from ichor.state import Module, Variant
 from ichor.assembler import FuncBuilder
 
@@ -22,59 +22,59 @@ NOT1 = BOOTSTRAP.define_function(
     f";not;{BOOL};{BOOL}",
     [
         # a: Bool
-        Opcode.IDENTIFIERC("bool"),
+        isa.IDENTIFIERC("bool"),
-        Opcode.TYPEREF(),  # <typeref bool> a
+        isa.TYPEREF(),  # <typeref bool> a
-        Opcode.DUP(),
+        isa.DUP(),
-        Opcode.IDENTIFIERC("true"),
+        isa.IDENTIFIERC("true"),
-        Opcode.VARIANTREF(), # <variantref true:bool> <typeref bool> a
+        isa.VARIANTREF(), # <variantref true:bool> <typeref bool> a
-        Opcode.DUP(),
+        isa.DUP(),
-        Opcode.SLOT(0),
+        isa.SLOT(0),
-        Opcode.ROT(2),
+        isa.ROT(2),
-        Opcode.VTEST(11),
+        isa.VTEST(11),
 
-        Opcode.VARIANT(0),
+        isa.VARIANT(0),
-        Opcode.RETURN(1),
+        isa.RETURN(1),
 
-        Opcode.DROP(1),
+        isa.DROP(1),
-        Opcode.IDENTIFIERC("false"),
+        isa.IDENTIFIERC("false"),
-        Opcode.VARIANTREF(),
+        isa.VARIANTREF(),
-        Opcode.VARIANT(0),
+        isa.VARIANT(0),
-        Opcode.RETURN(1),
+        isa.RETURN(1),
     ],
 )
 
 OR2 = BOOTSTRAP.define_function(
     f";or;{BOOL},{BOOL};{BOOL}",
     [
-        Opcode.BREAK(),
+        isa.BREAK(),
     ],
 )
 
 OR3 = BOOTSTRAP.define_function(
     f";or;{BOOL},{BOOL},{BOOL};{BOOL}",
     [
-        Opcode.BREAK(),
+        isa.BREAK(),
     ]
 )
 
 AND2 = BOOTSTRAP.define_function(
     f";and;{BOOL},{BOOL};{BOOL}",
     [
-        Opcode.BREAK(),
+        isa.BREAK(),
     ],
 )
 
 AND3 = BOOTSTRAP.define_function(
     f";and;{BOOL},{BOOL},{BOOL};{BOOL}",
     [
-        Opcode.BREAK(),
+        isa.BREAK(),
     ],
 )
 
 XOR2 = BOOTSTRAP.define_function(
     f";xor;{BOOL},{BOOL};{BOOL}",
     [
-        Opcode.BREAK(),
+        isa.BREAK(),
     ],
 )
 
@@ -82,6 +82,6 @@ XOR3 = BOOTSTRAP.define_function(
     f";xor;{BOOL},{BOOL},{BOOL};{BOOL}",
     [
         # A^B|B^C
-        Opcode.BREAK(),
+        isa.BREAK(),
     ]
 )

projects/shoggoth/src/python/ichor/impl.py

@@ -13,7 +13,7 @@ from copy import deepcopy
 import typing as t
 from textwrap import indent
 
-from ichor.isa import Opcode
+from ichor import isa
 from ichor.state import Closure, FunctionRef, Identifier, Module, Function, Type, TypeRef, VariantRef, Variant, Stackframe
 
 
@@ -52,7 +52,7 @@ class Interpreter(object):
             b = []
             b.append(f"clock {clock}:")
             b.append("  stack:")
-            for offset, it in zip(range(len(stackframe), 0, -1), stackframe):
+            for offset, it in zip(range(0, len(stackframe), 1), stackframe):
                 b.append(f"    {offset: <3} {it}")
             b.append(f"  op: {op}")
             print(indent("\n".join(b), "  " * stackframe.depth))
@@ -64,7 +64,7 @@ class Interpreter(object):
             clock += 1
 
             match op:
-                case Opcode.IDENTIFIERC(name):
+                case isa.IDENTIFIERC(name):
                     if not (name in mod.functions
                             or name in mod.types
                             or any(name in t.constructors for t in mod.types.values())):
@@ -72,7 +72,7 @@ class Interpreter(object):
 
                     stackframe.push(Identifier(name))
 
-                case Opcode.TYPEREF():
+                case isa.TYPEREF():
                     id = stackframe.pop()
                     if not isinstance(id, Identifier):
                         _error("TYPEREF consumes an identifier")
@@ -81,7 +81,7 @@ class Interpreter(object):
 
                     stackframe.push(TypeRef(id.name))
 
-                case Opcode.VARIANTREF():
+                case isa.VARIANTREF():
                     id: Identifier = stackframe.pop()
                     if not isinstance(id, Identifier):
                         _error("VARIANTREF consumes an identifier and a typeref")
@@ -96,7 +96,7 @@ class Interpreter(object):
 
                     stackframe.push(VariantRef(t, id.name))
 
-                case Opcode.VARIANT(n):
+                case isa.VARIANT(n):
                     armref: VariantRef = stackframe.pop()
                     if not isinstance(armref, VariantRef):
                         _error("VARIANT must be given a valid constructor reference")
@@ -114,7 +114,7 @@ class Interpreter(object):
                     stackframe.drop(n)
                     stackframe.push(v)
 
-                case Opcode.VTEST(n):
+                case isa.VTEST(n):
                     armref: VariantRef = stackframe.pop()
                     if not isinstance(armref, VariantRef):
                         _error("VTEST must be given a variant reference")
@@ -127,38 +127,38 @@ class Interpreter(object):
                         stackframe.goto(n)
                         continue
 
-                case Opcode.GOTO(n):
+                case isa.GOTO(n):
                     if (n < 0):
                         _error("Illegal branch target")
                     stackframe.goto(n)
                     continue
 
-                case Opcode.DUP(n):
+                case isa.DUP(n):
                     if (n > len(stackframe)):
                         _error("Stack size violation")
 
                     stackframe.dup(n)
 
-                case Opcode.ROT(n):
+                case isa.ROT(n):
                     if (n > len(stackframe)):
                         _error("Stack size violation")
 
                     stackframe.rot(n)
 
-                case Opcode.DROP(n):
+                case isa.DROP(n):
                     if (n > len(stackframe)):
                         _error("Stack size violation")
 
                     stackframe.drop(n)
 
-                case Opcode.SLOT(n):
+                case isa.SLOT(n):
                     if (n < 0):
                         _error("SLOT must have a positive reference")
                     if (n > len(stackframe) - 1):
                         _error("SLOT reference out of range")
                     stackframe.slot(n)
 
-                case Opcode.FUNREF():
+                case isa.FUNREF():
                     id = stackframe.pop()
                     if not isinstance(id, Identifier):
                         _error("FUNREF consumes an IDENTIFIER")
@@ -168,7 +168,7 @@ class Interpreter(object):
                     except:
                         _error("Invalid function ref")
 
-                case Opcode.CALLF(n):
+                case isa.CALLF(n):
                     sig = stackframe.pop()
                     if not isinstance(sig, FunctionRef):
                         _error("CALLF requires a funref at top of stack")
@@ -186,7 +186,7 @@ class Interpreter(object):
                     stackframe = stackframe.call(fun, ip)
                     continue
 
-                case Opcode.RETURN(n):
+                case isa.RETURN(n):
                     if (n > len(stackframe)):
                         _error("Stack size violation")
 
@@ -199,7 +199,7 @@ class Interpreter(object):
                     stackframe = stackframe.ret(n)
                     continue
 
-                case Opcode.CLOSUREF(n):
+                case isa.CLOSUREF(n):
                     sig = stackframe.pop()
                     if not isinstance(sig, FunctionRef):
                         _error("CLOSUREF requires a funref at top of stack")
@@ -216,7 +216,7 @@ class Interpreter(object):
                     stackframe.drop(n)
                     stackframe.push(c)
 
-                case Opcode.CLOSUREC(n):
+                case isa.CLOSUREC(n):
                     c = stackframe.pop()
                     if not isinstance(c, Closure):
                         _error("CLOSUREC requires a closure at top of stack")
@@ -233,7 +233,7 @@ class Interpreter(object):
                     stackframe.drop(n)
                     stackframe.push(c)
 
-                case Opcode.CALLC(n):
+                case isa.CALLC(n):
                     c = stackframe.pop()
                     if not isinstance(c, Closure):
                         _error("CALLC requires a closure at top of stack")
@@ -246,7 +246,7 @@ class Interpreter(object):
                     # Extract the function signature
 
                     # Push the closure's stack fragment
-                    stackframe._stack = stackframe._stack.extendleft(c.frag)
+                    stackframe._stack = c.frag + stackframe._stack
 
                     # Perform a "normal" funref call
                     try:

projects/shoggoth/src/python/ichor/isa.py

@@ -1,13 +1,24 @@
 """The instruction set for Shogoth."""
 
-
+from abc import ABC
+from dataclasses import dataclass
 import typing as t
 
 
-class Opcode:
+@dataclass
-    # Note that there's no IF, TRUE or FALSE required if bool is a builtin.
+class Label(object):
+    name: str
 
-    class GOTO(t.NamedTuple):
+    def __hash__(self):
+        return hash(self.name)
+
+
+class Opcode(ABC):
+    pass
+
+
+@dataclass
+class GOTO(Opcode):
     """() -> ()
 
     Branch to another point within the same bytecode segment. The target MUST be within the same module range as the
@@ -17,14 +28,15 @@ class Opcode:
 
     target: int
 
-    ####################################################################################################
+####################################################################################################
-    # Stack manipulation
+# Stack manipulation
-    ####################################################################################################
+####################################################################################################
-    # https://wiki.laptop.org/go/Forth_stack_operators
+# https://wiki.laptop.org/go/Forth_stack_operators
-    # https://www.forth.com/starting-forth/2-stack-manipulation-operators-arithmetic/
+# https://www.forth.com/starting-forth/2-stack-manipulation-operators-arithmetic/
-    # https://docs.oracle.com/javase/specs/jvms/se18/html/jvms-6.html#jvms-6.5.swap
+# https://docs.oracle.com/javase/specs/jvms/se18/html/jvms-6.html#jvms-6.5.swap
 
-    class DUP(t.NamedTuple):
+@dataclass
+class DUP(Opcode):
     """(A, B, ...) -> (A, B, ...)
 
     Duplicate the top N items of the stack.
@@ -33,7 +45,9 @@ class Opcode:
 
     nargs: int = 1
 
-    class ROT(t.NamedTuple):
+
+@dataclass
+class ROT(Opcode):
     """(A, B, ... Z) -> (Z, A, B, ...)
 
     Rotate the top N elements of the stack.
@@ -42,7 +56,8 @@ class Opcode:
 
     nargs: int = 2
 
-    class DROP(t.NamedTuple):
+@dataclass
+class DROP(Opcode):
     """(*) -> ()
 
     Drop the top N items of the stack.
@@ -51,7 +66,9 @@ class Opcode:
 
     nargs: int = 1
 
-    class SLOT(t.NamedTuple):
+
+@dataclass
+class SLOT(Opcode):
     """(..., A) -> (A, ..., A)
 
     Copy the Nth (counting up from 0 at the bottom of the stack) item to the top of the stack.
@@ -61,11 +78,12 @@ class Opcode:
 
     target: int
 
-    ####################################################################################################
+####################################################################################################
-    # Functional abstraction
+# Functional abstraction
-    ####################################################################################################
+####################################################################################################
 
-    class IDENTIFIERC(t.NamedTuple):
+@dataclass
+class IDENTIFIERC(Opcode):
     """() -> (IDENTIFIER)
 
     An inline constant which produces an identifier to the stack.
@@ -77,14 +95,17 @@ class Opcode:
 
     val: str
 
-    class FUNREF(t.NamedTuple):
+
+@dataclass
+class FUNREF(Opcode):
     """(IDENTIFIER) -> (`FUNREF<... A to ... B>`)
 
     Construct a reference to a static codepoint.
 
     """
 
-    class CALLF(t.NamedTuple):
+@dataclass
+class CALLF(Opcode):
     """(`FUNREF<... A to ... B>`, ... A) -> (... B)
 
     Call [funref]
@@ -99,7 +120,8 @@ class Opcode:
 
     nargs: int = 0
 
-    class RETURN(t.NamedTuple):
+@dataclass
+class RETURN(Opcode):
     """(... A) -> ()
 
     Return to the source of the last `CALL`. The returnee will see the top `nargs` values of the present stack
@@ -114,7 +136,8 @@ class Opcode:
     nargs: int
 
 
-    class CLOSUREF(t.NamedTuple):
+@dataclass
+class CLOSUREF(Opcode):
     """(`FUNREF<A, ... B to ... C>`, A) -> (`CLOSURE<... B to ... C>`)
 
     Construct a closure over the function reference at the top of the stack. This may produce nullary closures.
@@ -123,7 +146,9 @@ class Opcode:
 
     nargs: int = 0
 
-    class CLOSUREC(t.NamedTuple):
+
+@dataclass
+class CLOSUREC(Opcode):
     """(`CLOSURE<A, ... B to ... C>`, A) -> (`CLOSURE<... B to ... C>`)
 
     Further close over the closure at the top of the stack. This may produce nullary closures.
@@ -132,7 +157,8 @@ class Opcode:
 
     nargs: int = 0
 
-    class CALLC(t.NamedTuple):
+
+class CALLC(Opcode):
     """(`CLOSURE<... A to ... B>`, ... A) -> (... B)
 
     Call [closure]
@@ -147,27 +173,32 @@ class Opcode:
 
     nargs: int = 0
 
-    ####################################################################################################
+####################################################################################################
-    # Structures
+# Structures
-    ####################################################################################################
+####################################################################################################
 
-    # FIXME: This lacks any sort of way to do dynamic type/field references
+# FIXME: This lacks any sort of way to do dynamic type/field references
 
-    class TYPEREF(t.NamedTuple):
+@dataclass
+class TYPEREF(Opcode):
     """(IDENTIFIER) -> (TYPEREF)
 
     Produces a TYPEREF to the type named by the provided IDENTIFIER.
 
     """
 
-    class VARIANTREF(t.NamedTuple):
+
+@dataclass
+class VARIANTREF(Opcode):
     """(IDENTIFIER, TYPEREF) -> (VARIANTREF)
 
     Produce a VARIANTREF to an 'arm' of the given variant type.
 
     """
 
-    class VARIANT(t.NamedTuple):
+
+@dataclass
+class VARIANT(Opcode):
     """(VARIANTREF<a ⊢ A ⊂ B>, ...) -> (B)
 
     Construct an instance of an 'arm' of a variant.
@@ -180,7 +211,9 @@ class Opcode:
 
     nargs: int = 0
 
-    class VTEST(t.NamedTuple):
+
+@dataclass
+class VTEST(Opcode):
     """(VARIANTREF<a ⊢ A ⊂ B>, B) -> ()
 
     Test whether B is a given arm of a variant A .
@@ -191,7 +224,9 @@ class Opcode:
 
     target: int
 
-    class VLOAD(t.NamedTuple):
+
+@dataclass
+class VLOAD(Opcode):
     """(VARIANTREF<a ⊢ A ⊂ B>, B) -> (A)
 
     Load the value of the variant arm.
@@ -200,6 +235,8 @@ class Opcode:
 
     """
 
-    class BREAK(t.NamedTuple):
+
+@dataclass
+class BREAK(Opcode):
     """Abort the interpreter."""
     pass

projects/shoggoth/src/python/ichor/state.py

@@ -4,7 +4,7 @@
 
 import typing as t
 
-from ichor.isa import Opcode
+from ichor import isa
 
 from pyrsistent import pdeque, PDeque
 from lark import Lark, Transformer, v_args, Token
@@ -77,13 +77,13 @@ class Function(t.NamedTuple):
     name: str
     arguments: t.List[str]
     returns: t.List[str]
-    instructions: t.List[Opcode]
+    instructions: t.List[isa.Opcode]
     typevars: t.List[t.Any] = []
     typeconstraints: t.List[t.Any] = []
     metadata: dict = {}
 
     @classmethod
-    def build(cls, name: str, instructions: t.List[Opcode]):
+    def build(cls, name: str, instructions: t.List[isa.Opcode]):
         constraints, name, args, rets = FUNC.parse(name)
         # FIXME: Constraints probably needs some massaging
         # FIXME: Need to get typevars from somewhere
@@ -188,18 +188,18 @@ class Module(t.NamedTuple):
         )
 
     @staticmethod
-    def translate(start: int, end: int, i: Opcode):
+    def translate(start: int, end: int, i: isa.Opcode):
         # FIXME: Consolidate bounds checks somehow
         match i:
-            case Opcode.VTEST(t):
+            case isa.VTEST(t):
                 d = t + start
                 assert start <= d < end
-                return Opcode.VTEST(d)
+                return isa.VTEST(d)
 
-            case Opcode.GOTO(t):
+            case isa.GOTO(t):
                 d = t + start
                 assert start <= d < end
-                return Opcode.GOTO(d)
+                return isa.GOTO(d)
 
             case _:
                 return i
@@ -279,7 +279,10 @@ class Stackframe(object):
         self._stack = self._stack[:-nargs]
 
     def rot(self, nargs):
-        self._stack[nargs:].extend(rotate(self._stack[:nargs]))
+        frag = self._stack[-nargs:]
+        base = self._stack[:-nargs]
+        rotated = rotate(frag)
+        self._stack = base + rotated
 
     def slot(self, n):
         self.push(self._stack[n])

projects/shoggoth/test/python/ichor/test_assembler.py

@@ -1,6 +1,6 @@
 #!/usr/bin/env python3
 
-from ichor import FuncBuilder, Opcode
+from ichor import FuncBuilder, isa
 
 import pytest
 
@@ -11,37 +11,37 @@ def builder() -> FuncBuilder:
 
 def test_forwards_label(builder: FuncBuilder):
     l = builder.make_label()
-    builder.write(Opcode.GOTO(l))
+    builder.write(isa.GOTO(l))
-    builder.write(Opcode.DROP(0)) # no-op
+    builder.write(isa.DROP(0)) # no-op
-    builder.set_label(l)
+    builder.write(l)
-    builder.write(Opcode.DROP(0)) # no-op
+    builder.write(isa.DROP(0)) # no-op
     instrs = builder.build()
     assert instrs == [
-        Opcode.GOTO(2),
+        isa.GOTO(2),
-        Opcode.DROP(0),
+        isa.DROP(0),
-        Opcode.DROP(0),
+        isa.DROP(0),
     ]
 
 
 def test_backwards_label(builder: FuncBuilder):
     l = builder.make_label()
-    builder.set_label(l)
+    builder.write(l)
-    builder.write(Opcode.DROP(0)) # no-op
+    builder.write(isa.DROP(0)) # no-op
-    builder.write(Opcode.GOTO(l))
+    builder.write(isa.GOTO(l))
     instrs = builder.build()
     assert instrs == [
-        Opcode.DROP(0),
+        isa.DROP(0),
-        Opcode.GOTO(0),
+        isa.GOTO(0),
     ]
 
 
 def test_self_label(builder: FuncBuilder):
     l = builder.make_label()
-    builder.write(Opcode.DROP(0)) # no-op
+    builder.write(isa.DROP(0)) # no-op
-    builder.set_label(l)
+    builder.write(l)
-    builder.write(Opcode.GOTO(l))
+    builder.write(isa.GOTO(l))
     instrs = builder.build()
     assert instrs == [
-        Opcode.DROP(0),
+        isa.DROP(0),
-        Opcode.GOTO(1),
+        isa.GOTO(1),
     ]

projects/shoggoth/test/python/ichor/test_bootstrap.py

@@ -2,7 +2,7 @@
 
 from .fixtures import *  # noqa
 
-from ichor import *
+from ichor import isa, TRUE, FALSE, NOT1
 import pytest
 
 
@@ -12,10 +12,10 @@ import pytest
 ])
 def test_not(vm, stack, ret):
     assert vm.run([
-        Opcode.IDENTIFIERC(NOT1),
+        isa.IDENTIFIERC(NOT1),
-        Opcode.FUNREF(),
+        isa.FUNREF(),
-        Opcode.CALLF(1),
+        isa.CALLF(1),
-        Opcode.RETURN(1)
+        isa.RETURN(1)
     ], stack = stack) == ret
 
 
@@ -27,10 +27,10 @@ def test_not(vm, stack, ret):
 # ])
 # def test_or(vm, stack, ret):
 #     assert vm.run([
-#         Opcode.IDENTIFIERC(OR2),
+#         isa.IDENTIFIERC(OR2),
-#         Opcode.FUNREF(),
+#         isa.FUNREF(),
-#         Opcode.CALLF(2),
+#         isa.CALLF(2),
-#         Opcode.RETURN(1)
+#         isa.RETURN(1)
 #     ], stack = stack) == ret
 
 
@@ -42,10 +42,10 @@ def test_not(vm, stack, ret):
 # ])
 # def test_and(vm, stack, ret):
 #     assert vm.run([
-#         Opcode.IDENTIFIERC(AND2),
+#         isa.IDENTIFIERC(AND2),
-#         Opcode.FUNREF(),
+#         isa.FUNREF(),
-#         Opcode.CALLF(2),
+#         isa.CALLF(2),
-#         Opcode.RETURN(1)
+#         isa.RETURN(1)
 #     ], stack = stack) == ret
 
 
@@ -57,10 +57,10 @@ def test_not(vm, stack, ret):
 # ])
 # def test_xor2(vm, stack, ret):
 #     assert vm.run([
-#         Opcode.IDENTIFIERC(XOR2),
+#         isa.IDENTIFIERC(XOR2),
-#         Opcode.FUNREF(),
+#         isa.FUNREF(),
-#         Opcode.CALLF(2),
+#         isa.CALLF(2),
-#         Opcode.RETURN(1)
+#         isa.RETURN(1)
 #     ], stack = stack) == ret
 
 
@@ -75,10 +75,10 @@ def test_not(vm, stack, ret):
 # ])
 # def test_xor3(vm, stack, ret):
 #     assert vm.run([
-#         Opcode.IDENTIFIERC(XOR3),
+#         isa.IDENTIFIERC(XOR3),
-#         Opcode.FUNREF(),
+#         isa.FUNREF(),
-#         Opcode.CALLF(3),
+#         isa.CALLF(3),
-#         Opcode.RETURN(1)
+#         isa.RETURN(1)
 #     ], stack = stack) == ret
 
 
@@ -87,9 +87,9 @@ def test_not(vm, stack, ret):
 # ])
 # def test_funref(vm, stack, ret):
 #     assert vm.run([
-#         Opcode.IDENTIFIERC(NOT1),
+#         isa.IDENTIFIERC(NOT1),
-#         Opcode.FUNREF(),
+#         isa.FUNREF(),
-#         Opcode.RETURN(1)
+#         isa.RETURN(1)
 #     ], stack = stack) == ret
 
 
@@ -98,10 +98,10 @@ def test_not(vm, stack, ret):
 # ])
 # def test_callf(vm, stack, ret):
 #     assert vm.run([
-#         Opcode.IDENTIFIERC(NOT1),
+#         isa.IDENTIFIERC(NOT1),
-#         Opcode.FUNREF(),
+#         isa.FUNREF(),
-#         Opcode.CALLF(1),
+#         isa.CALLF(1),
-#         Opcode.RETURN(1)
+#         isa.RETURN(1)
 #     ], stack = stack) == ret
 
 
@@ -113,11 +113,11 @@ def test_not(vm, stack, ret):
 # ])
 # def test_callc(vm, stack, ret):
 #     assert vm.run([
-#         Opcode.IDENTIFIERC(XOR2),
+#         isa.IDENTIFIERC(XOR2),
-#         Opcode.FUNREF(),
+#         isa.FUNREF(),
-#         Opcode.CLOSUREF(1),
+#         isa.CLOSUREF(1),
-#         Opcode.CALLC(1),
+#         isa.CALLC(1),
-#         Opcode.RETURN(1),
+#         isa.RETURN(1),
 #     ], stack = stack) == ret
 
 
@@ -132,10 +132,10 @@ def test_not(vm, stack, ret):
 # ])
 # def test_closurec(vm, stack, ret):
 #     assert vm.run([
-#         Opcode.IDENTIFIERC(XOR3),
+#         isa.IDENTIFIERC(XOR3),
-#         Opcode.FUNREF(),
+#         isa.FUNREF(),
-#         Opcode.CLOSUREF(1),
+#         isa.CLOSUREF(1),
-#         Opcode.CLOSUREC(1),
+#         isa.CLOSUREC(1),
-#         Opcode.CALLC(1),
+#         isa.CALLC(1),
-#         Opcode.RETURN(1),
+#         isa.RETURN(1),
 #     ], stack = stack) == ret

projects/shoggoth/test/python/ichor/test_interpreter.py

@@ -4,59 +4,64 @@ Tests coverign the VM interpreter
 
 from .fixtures import *  # noqa
 
-from ichor import *
+from ichor import isa, InterpreterError, TRUE, FALSE
 import pytest
 
 
 def test_return(vm):
-    assert vm.run([Opcode.RETURN(0)], stack=[TRUE, FALSE]) == []
+    assert vm.run([isa.RETURN(0)], stack=[TRUE, FALSE]) == []
-    assert vm.run([Opcode.RETURN(1)], stack=[TRUE, FALSE]) == [TRUE]
+    assert vm.run([isa.RETURN(1)], stack=[TRUE, FALSE]) == [TRUE]
-    assert vm.run([Opcode.RETURN(2)], stack=[TRUE, FALSE]) == [TRUE, FALSE]
+    assert vm.run([isa.RETURN(2)], stack=[TRUE, FALSE]) == [TRUE, FALSE]
 
 
 def test_dup(vm):
-    assert vm.run([Opcode.DUP(1), Opcode.RETURN(3)], stack=[FALSE, TRUE]) == [FALSE, TRUE, TRUE]
+    assert vm.run([isa.DUP(1), isa.RETURN(3)], stack=[FALSE, TRUE]) == [FALSE, TRUE, TRUE]
-    assert vm.run([Opcode.DUP(2), Opcode.RETURN(4)], stack=[FALSE, TRUE]) == [FALSE, TRUE, FALSE, TRUE]
+    assert vm.run([isa.DUP(2), isa.RETURN(4)], stack=[FALSE, TRUE]) == [FALSE, TRUE, FALSE, TRUE]
 
 
 def test_rot(vm):
     assert vm.run([
-        Opcode.ROT(2),
+        isa.ROT(2),
-        Opcode.RETURN(2)
+        isa.RETURN(2)
     ], stack=[FALSE, TRUE]) == [TRUE, FALSE]
 
     assert vm.run([
-        Opcode.ROT(3),
+        isa.ROT(2),
-        Opcode.RETURN(3)
+        isa.RETURN(5)
+    ], stack=[TRUE, TRUE, TRUE, FALSE, TRUE]) == [TRUE, TRUE, TRUE, TRUE, FALSE]
+
+    assert vm.run([
+        isa.ROT(3),
+        isa.RETURN(3)
     ], stack=[FALSE, TRUE, FALSE]) == [FALSE, FALSE, TRUE]
 
 
 def test_drop(vm):
     assert vm.run([
-        Opcode.DROP(1),
+        isa.DROP(1),
-        Opcode.RETURN(1)
+        isa.RETURN(1)
     ], stack=[TRUE, FALSE]) == [TRUE]
 
 
 def test_dup_too_many(vm):
     with pytest.raises(InterpreterError):
-        vm.run([Opcode.DUP(1)])
+        vm.run([isa.DUP(1)])
 
     with pytest.raises(InterpreterError):
-        vm.run([Opcode.FALSE(), Opcode.DUP(2)])
+        vm.run([isa.DUP(2)], stack=[FALSE])
 
 
 def test_rot_too_many(vm):
     with pytest.raises(InterpreterError):
-        vm.run([Opcode.ROT(1)])
+        vm.run([isa.ROT(1)])
 
     with pytest.raises(InterpreterError):
-        vm.run([Opcode.TRUE(), Opcode.ROT(2)])
+        vm.run([isa.ROT(2)], stack=[FALSE])
 
 
 def test_drop_too_many(vm):
     with pytest.raises(InterpreterError):
-        vm.run([Opcode.DROP(1)])
+        vm.run([isa.DROP(1)])
 
     with pytest.raises(InterpreterError):
-        vm.run([Opcode.TRUE(), Opcode.DROP(2)])
+        vm.run([isa.DROP(2)], stack=[FALSE])

projects/shoggoth/test/python/ichor/test_state.py

@@ -70,3 +70,15 @@ def test_stackframe_slot(frame):
 
     frame.slot(2)
     assert frame.pop() == 2
+
+
+def test_stackframe_rot(frame):
+    frame.push(0)
+    frame.push(1)
+    frame.push(2)
+    frame.push(3)
+    frame.push(4)
+
+    frame.rot(2)
+    assert frame.pop() == 3
+    assert frame.pop() == 4