diff --git a/artiq/gateware/wrpll/thls.py b/artiq/gateware/wrpll/thls.py
index 04c68628c..a3e97f32f 100644
--- a/artiq/gateware/wrpll/thls.py
+++ b/artiq/gateware/wrpll/thls.py
@@ -29,35 +29,28 @@ class Isn:
 
 
 class NopIsn(Isn):
-    pass
-
+    opcode = 0
 
 class AddIsn(Isn):
-    pass
-
+    opcode = 1
 
 class SubIsn(Isn):
-    pass
-
+    opcode = 2
 
 class MulIsn(Isn):
-    pass
-
+    opcode = 3
 
 class ShiftIsn(Isn):
-    pass
-
+    opcode = 4
 
 class CopyIsn(Isn):
-    pass
-
+    opcode = 5
 
 class InputIsn(Isn):
-    pass
-
+    opcode = 6
 
 class OutputIsn(Isn):
-    pass
+    opcode = 7
 
 
 class ASTCompiler:
@@ -126,8 +119,13 @@ class ASTCompiler:
 
 
 class Processor:
-    def __init__(self, multiplier_stages=2):
+    def __init__(self, data_width=32, multiplier_stages=2):
+        self.data_width = data_width
         self.multiplier_stages = multiplier_stages
+        self.program_rom_size = None
+        self.data_ram_size = None
+        self.opcode_bits = 3
+        self.reg_bits = None
 
     def get_instruction_latency(self, isn):
         return {
@@ -139,6 +137,29 @@ class Processor:
             InputIsn: 1
         }[isn.__class__]
 
+    def encode_instruction(self, isn, exit):
+        opcode = isn.opcode
+        if isn.immediate is not None:
+            r0 = isn.immediate
+            if len(isn.inputs) >= 1:
+                r1 = isn.inputs[0]
+            else:
+                r1 = 0
+        else:
+            if len(isn.inputs) >= 1:
+                r0 = isn.inputs[0]
+            else:
+                r0 = 0
+            if len(isn.inputs) >= 2:
+                r1 = isn.inputs[1]
+            else:
+                r1 = 0
+        r = 0
+        for value, bits in ((exit, self.reg_bits), (r1, self.reg_bits), (r0, self.reg_bits), (opcode, self.opcode_bits)):
+            r <<= bits
+            r |= value
+        return r
+
 
 class Scheduler:
     def __init__(self, processor, reserved_data, program):
@@ -218,15 +239,36 @@ class Scheduler:
         self.output += [NopIsn()]*(max(self.exits.keys()) - len(self.output) + 1)
         return self.output
 
+
+class CompiledProgram:
+    def __init__(self, processor, program, exits, data, glbs):
+        self.processor = processor
+        self.program = program
+        self.exits = exits
+        self.data = data
+        self.globals = glbs
+
     def pretty_print(self):
-        for cycle, isn in enumerate(self.output):
+        for cycle, isn in enumerate(self.program):
             l = "{:4d} {:15}".format(cycle, str(isn))
             if cycle in self.exits:
-                l += " -> r{}".format(self.exits[cycle][1])
+                l += " -> r{}".format(self.exits[cycle])
             print(l)
 
+    def dimension_memories(self):
+        self.processor.program_rom_size = len(self.program)
+        self.processor.data_ram_size = len(self.data)
+        self.processor.reg_bits = (self.processor.data_ram_size - 1).bit_length()
 
-def compile(function):
+    def encode(self):
+        r = []
+        for i, isn in enumerate(self.program):
+            exit = self.exits.get(i, 0)
+            r.append(self.processor.encode_instruction(isn, exit))
+        return r
+
+
+def compile(processor, function):
     node = ast.parse(inspect.getsource(function))
     assert isinstance(node, ast.Module)
     assert len(node.body) == 1
@@ -244,12 +286,16 @@ def compile(function):
     arg_r = astcompiler.input(arg)
     for node in body:
         astcompiler.emit(node)
-    print(astcompiler.data)
-    print(astcompiler.program)
 
-    scheduler = Scheduler(Processor(), len(astcompiler.data), astcompiler.program)
+    scheduler = Scheduler(processor, len(astcompiler.data), astcompiler.program)
     scheduler.schedule()
-    scheduler.pretty_print()
+
+    return CompiledProgram(
+        processor=processor,
+        program=scheduler.output,
+        exits={k: v[1] for k,v in scheduler.exits.items()},
+        data=astcompiler.data,
+        glbs=astcompiler.globals)
 
 
 a = 0
@@ -264,4 +310,7 @@ def foo(x):
     return 4748*a + 259*b - 155*c 
 
 
-compile(foo)
+cp = compile(Processor(), foo)
+cp.pretty_print()
+cp.dimension_memories()
+print(cp.encode())