Support do { .. } while (..), allow for empty compound statements (e.g. do{}while(1))

1 files changed, 15 insertions, 5 deletions

diff --git a/pp2cc.py b/pp2cc.py
index 4a1a1b3..045cdb9 100755
--- a/pp2cc.py
+++ b/pp2cc.py
@@ -320,8 +320,9 @@ class Parse(object):
     def parseCompound(self, linked_node):
         linked_node.incrementLevel()
         lines = []
-        for cn in linked_node.node.block_items:
-            lines += self.parseStatement(cn, linked_node)
+        if linked_node.node.block_items:
+            for cn in linked_node.node.block_items:
+                lines += self.parseStatement(cn, linked_node)
         return lines
 
     def parseBinaryLogicalOp(self, linked_node):
@@ -694,6 +695,17 @@ class Parse(object):
     def parseCast(self, linked_node):
         self.logger.warning("Found a type cast, but these are unsupported.", linked_node=linked_node)
         return self.parseStatement(linked_node.node.expr, linked_node)
+    def parseDoWhile(self, linked_node):
+        node = linked_node.node
+        lbl_do = self.uniqLbl("do")
+        # provides a way to redo the loop
+        lines = [self.asm.noop(lbl_do)]
+        # do { ... }, expect do{/*empty*/} as well
+        lines += self.parseStatement(node.stmt, linked_node)
+        # while (...)
+        lines += self.parseStatement(node.cond, linked_node)
+        lines.append(self.asm.branch_op("BNE", lbl_do))
+        return lines
     def parseStatement(self, node, parent_linked_node, level_increment=False):
         linked_node = LinkedNode(node, parent_linked_node, level_increment=level_increment)
         self.asm.level = linked_node.level
@@ -702,8 +714,6 @@ class Parse(object):
             raise RuntimeError("Not implemented for type " + repr(node))
         elif isinstance(node, c_ast.Decl):
             self.defineGlobalVar(linked_node, parent_linked_node)
-        elif isinstance(node, c_ast.DoWhile):
-            raise RuntimeError("Not implemented for type " + repr(node))
         elif isinstance(node, c_ast.ExprList):
             raise RuntimeError("Not implemented for type " + repr(node))
         elif isinstance(node, c_ast.For):
@@ -717,7 +727,7 @@ class Parse(object):
         else:
             for entry in ("Compound", "BinaryOp", "If", "Constant", "ID",
                           "Return", "FuncCall", "UnaryOp", "Cast",
-                          "TernaryOp"):
+                          "TernaryOp", "DoWhile"):
                 if isinstance(node, getattr(c_ast, entry)):
                     lines += getattr(self, "parse" + entry)(linked_node)
                     break