--- old/src/cpu/x86/vm/assembler_x86.cpp	2015-08-12 14:08:53.000000000 +0200
+++ new/src/cpu/x86/vm/assembler_x86.cpp	2015-08-12 14:08:53.000000000 +0200
@@ -3498,6 +3498,14 @@
   emit_arith_b(0xF6, 0xC0, dst, imm8);
 }
 
+void Assembler::testb(Address dst, int8_t imm8) {
+  InstructionMark im(this);
+  prefix(dst);
+  emit_int8((unsigned char)0xF6);
+  emit_operand(rax, dst, 1);
+  emit_int8((unsigned char)imm8);
+}
+
 void Assembler::testl(Register dst, int32_t imm32) {
   // not using emit_arith because test
   // doesn't support sign-extension of