Enforce asm restrictions on switch more precisely.

src/typing-asm.cc

Index: src/typing-asm.cc
diff --git a/src/typing-asm.cc b/src/typing-asm.cc
index a062b733c846d49b58ab97939459a51fda50be4c..509ba7b1253c9d07325533c4ec3fa78a110d7d7d 100644
--- a/src/typing-asm.cc
+++ b/src/typing-asm.cc
@@ -2,10 +2,12 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "src/v8.h"
-
 #include "src/typing-asm.h"
 
+#include <limits>
+
+#include "src/v8.h"
+
 #include "src/ast/ast.h"
 #include "src/ast/scopes.h"
 #include "src/codegen.h"
@@ -386,9 +388,14 @@ void AsmTyper::VisitSwitchStatement(SwitchStatement* stmt) {
   RECURSE(VisitWithExpectation(stmt->tag(), cache_.kAsmSigned,
                                "switch expression non-integer"));
   ZoneList<CaseClause*>* clauses = stmt->cases();
+  ZoneSet<int32_t> cases(zone());
   for (int i = 0; i < clauses->length(); ++i) {
     CaseClause* clause = clauses->at(i);
-    if (!clause->is_default()) {
+    if (clause->is_default()) {
+      if (i != clauses->length() - 1) {
+        FAIL(clause, "default case out of order");
+      }
+    } else {
       Expression* label = clause->label();
       RECURSE(VisitWithExpectation(label, cache_.kAsmSigned,
                                    "case label non-integer"));
@@ -396,11 +403,22 @@ void AsmTyper::VisitSwitchStatement(SwitchStatement* stmt) {
       Handle<Object> value = label->AsLiteral()->value();
       int32_t value32;
       if (!value->ToInt32(&value32)) FAIL(label, "illegal case label value");
+      if (cases.find(value32) != cases.end()) {
+        FAIL(label, "duplicate case value");
+      }
+      cases.insert(value32);
     }
     // TODO(bradnelson): Detect duplicates.
     ZoneList<Statement*>* stmts = clause->statements();
     RECURSE(VisitStatements(stmts));
   }
+  if (cases.size() > 0) {
+    int64_t min_case = *cases.begin();
+    int64_t max_case = *cases.rbegin();
+    if (max_case - min_case > std::numeric_limits<int32_t>::max()) {
+      FAIL(stmt, "case range too large");
+    }
+  }
 }