On MIPS, uses more branch delay slots.

runtime/vm/assembler_mips.cc

Index: runtime/vm/assembler_mips.cc
===================================================================
--- runtime/vm/assembler_mips.cc	(revision 22187)
+++ runtime/vm/assembler_mips.cc	(working copy)
@@ -361,11 +361,18 @@
     lw(RA, Address(SP, 2 * kWordSize));
     lw(FP, Address(SP, 1 * kWordSize));
     lw(PP, Address(SP, 0 * kWordSize));
-    addiu(SP, SP, Immediate(4 * kWordSize));
   } else {
     mov(SP, FP);
     lw(RA, Address(SP, 1 * kWordSize));
     lw(FP, Address(SP, 0 * kWordSize));
+  }
+}
+
+
+void Assembler::LeaveStubFrameSPRestore(bool uses_pp) {
+  if (uses_pp) {
+    addiu(SP, SP, Immediate(4 * kWordSize));
+  } else {
     addiu(SP, SP, Immediate(3 * kWordSize));
   }
 }