From 538cf03964d804c5da66385acd725b9449dfae09 Mon Sep 17 00:00:00 2001
From: Peter Wu <lekensteyn@gmail.com>
Date: Fri, 9 Dec 2011 15:46:41 +0000
Subject: Support nested case/default labels

---
 pp2cc.py            | 50 +++++++++++++++++++++++++++++---------------------
 tests/switch-case.c | 21 +++++++++++++++++++++
 2 files changed, 50 insertions(+), 21 deletions(-)
 create mode 100644 tests/switch-case.c

diff --git a/pp2cc.py b/pp2cc.py
index ac00ffd..6205e94 100755
--- a/pp2cc.py
+++ b/pp2cc.py
@@ -1139,29 +1139,37 @@ class Parse(object):
         switch_end = self.uniqLbl("switchEnd")
         linked_node.setBreak(switch_end)
         lbl_default = None
+
         for cn in stmt.block_items:
             linked_cn = LinkedNode(cn, linked_node)
-            if linked_cn.type == "Case":
-                lbl_case = self.uniqLbl("case")
-                try:
-                    case_val = self.determineConstValue(LinkedNode(cn.expr,
-                                                                   linked_cn))
-                except RuntimeError:
-                    e = sys.exc_info()[1]
-                    print "case label does not reduce to an integer constant"
-                    print e
-                    raise
-
-                lines_cases.append(self.asm.binary_op("CMP", switch_reg, case_val))
-                lines_cases.append(self.asm.branch_op("BEQ", lbl_case))
-                lines_stmts.append(self.asm.noop(lbl_case))
-                lines_stmts += self.parseStatement(cn.stmt, linked_cn)
-            elif linked_cn.type == "Default":
-                lbl_default = self.uniqLbl("default")
-                lines_stmts.append(self.asm.noop(lbl_default))
-                lines_stmts += self.parseStatement(cn.stmt, linked_cn)
-            else:
-                lines_stmts += self.parseStatement(cn, linked_cn)
+            while linked_cn is not None:
+                cn = linked_cn.node
+                if linked_cn.type == "Case":
+                    lbl_case = self.uniqLbl("case")
+                    try:
+                        case_val = self.determineConstValue(LinkedNode(cn.expr,
+                                                                       linked_cn))
+                    except RuntimeError:
+                        e = sys.exc_info()[1]
+                        print "case label does not reduce to an integer constant"
+                        print e
+                        raise
+    
+                    lines_cases.append(self.asm.binary_op("CMP", switch_reg, case_val))
+                    lines_cases.append(self.asm.branch_op("BEQ", lbl_case))
+                    lines_stmts.append(self.asm.noop(lbl_case))
+                    linked_cn = LinkedNode(cn.stmt, linked_cn.parent)
+                elif linked_cn.type == "Default":
+                    lbl_default = self.uniqLbl("default")
+                    lines_stmts.append(self.asm.noop(lbl_default))
+                    linked_cn = LinkedNode(cn.stmt, linked_cn.parent)
+                if linked_cn.type in ("Case", "Default"):
+                    # nested case/default labels like case 1: case 2: stmt;
+                    pass
+                else:
+                    # regular body
+                    lines_stmts += self.parseStatement(linked_cn.node, linked_cn.parent)
+                    linked_cn = None
         lines += lines_cases
         if lbl_default:
             lines.append(self.asm.branch_op("BRA", lbl_default))
diff --git a/tests/switch-case.c b/tests/switch-case.c
new file mode 100644
index 0000000..03d9bdc
--- /dev/null
+++ b/tests/switch-case.c
@@ -0,0 +1,21 @@
+int f(int n) {
+    switch (n) {
+        case 1:
+        case 2:
+            return 1;
+        case 3:
+            return 3;
+        case 4:
+            break;
+        default:
+            return 5;
+    }
+    return 4;
+}
+
+int main() {
+    int a;
+    // 1 + 1 +  3 + 4 + 5 = 14
+    a = f(1) + f(2) + f(3) + f(4) + f(5);
+    return a;// 14, 0xe
+}
-- 
cgit v1.2.1