Move some of the scaffolding into a more permanent function.

stepper.py

@@ -504,6 +504,53 @@ def alloc_globals(gdecls, heap):
     return global_env
 
 
+def auto_step(ast, function_name='tigermain', function_args=[1234, 5678]):
+    tdecls = ast.tdecls
+    fdecls = ast.fdecls
+    gdecls = ast.gdecls
+
+    function = fdecls[function_name]
+    body = function.body
+    first_block = body.first_block
+    blocks = body.named_blocks
+    insns = first_block.insns
+    terminator = first_block.terminator
+    stack_frames = []
+    ssa_env = {par[1]: arg for par, arg in zip(function.parameters, function_args)}
+    heap = [None]
+    call_res = []
+
+    global_env = alloc_globals(gdecls, heap)
+    print('Heap after globals are allocated:')
+    print(heap)
+
+    step_cnt = 0
+    while True:
+        (insns, terminator, blocks,
+         stack_frames, ssa_env, heap, call_res) = step(insns, terminator, blocks,
+                                                       stack_frames, ssa_env,
+                                                       global_env, heap, tdecls,
+                                                       fdecls, call_res)
+        step_cnt += 1
+        if terminator is None:
+            print('Stepping done!\nFinal ssa_env: {}'
+                  .format(ssa_env))
+            print('Final heap: {}'
+                  .format(heap))
+            print('Program resulted in {} after {} steps'.
+                  format(insns[0][1].val, step_cnt))
+            break
+
+        if step_cnt % 100 == 0:
+            while True:
+                stop_q = input('We have now done {} steps. Continue? [Y/n]: '
+                               .format(step_cnt)).lower()
+                if stop_q in ['y', 'yes', 'n', 'no', '']:
+                    break
+            if stop_q in ['n', 'no']:
+                break
+
+
 def gogo():
     p = parser.LLVMParser()
     p.build()
@@ -525,49 +572,9 @@ define i64 @tigermain (i64 %U_mainSL_8, i64 %U_mainDummy_9) {
     print(data)
     ast = p.parse(data)
 
-    tdecs = ast.tdecls
+    auto_step(ast)
-    fdecs = ast.fdecls
+    if True:
-    gdecs = ast.gdecls
+        return
-
-    tigermain = ast.fdecls['tigermain']
-    first_block = tigermain.body.first_block
-    blocks = tigermain.body.named_blocks
-    insns = first_block.insns
-    terminator = first_block.terminator
-    stack_frames = []
-    ssa_env = {}
-    heap = [None]
-    call_res = []
-
-    step_cnt = 0
-
-    global_env = alloc_globals(gdecs, heap)
-
-    while True:
-        (insns, terminator, blocks,
-         stack_frames, ssa_env, heap, call_res) = step(insns, terminator, blocks,
-                                                       stack_frames, ssa_env,
-                                                       global_env, heap, tdecs,
-                                                       fdecs, call_res)
-        step_cnt += 1
-        if terminator is None:
-            print('Stepping done!\nFinal ssa_env: {}'
-                  .format(ssa_env))
-            print('Final heap: {}'
-                  .format(heap))
-            print('Program resulted in {}'.
-                  format(insns[0][1].val))
-            break
-
-        if step_cnt % 100 == 0:
-            print(heap)
-            while True:
-                stop_q = input('We have now done {} steps. Continue? [Y/n]: '
-                               .format(step_cnt)).lower()
-                if stop_q in ['y', 'yes', 'n', 'no', '']:
-                    break
-            if stop_q in ['n', 'no']:
-                break
 
 
 if __name__ == '__main__':