ARM/ARM64: Fix smashed CODE_REG in intrinsics with InvokeMathCFunctionInstrs.

tests/lib/math/call_cmath_box_failure_path_test.dart

+// Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// VMOptions=--optimization-counter-threshold=-1 --new_gen_semi_max_size=2
+
+import 'dart:math';
+
+main() {
+  // 2MB / 16 bytes = 125000 allocations
+
+  for (var i = 0; i < 500000; i++) {
+    sin(i);
+  }
+
+  for (var i = 0; i < 500000; i++) {
+    cos(i);
+  }
+
+  for (var i = 0; i < 500000; i++) {
+    i.toDouble().truncateToDouble();
+  }
+}