Extends testb and cmpb/cmpw instruction support in the ia32 assembler.

src/ia32/assembler-ia32-inl.h

Index: src/ia32/assembler-ia32-inl.h
diff --git a/src/ia32/assembler-ia32-inl.h b/src/ia32/assembler-ia32-inl.h
index cd09e928df49702c33199770d8f32fd995b72537..cafa6763fa4dbfe543c054e9f74dc0b46c156e84 100644
--- a/src/ia32/assembler-ia32-inl.h
+++ b/src/ia32/assembler-ia32-inl.h
@@ -451,6 +451,11 @@ void Assembler::emit_code_relative_offset(Label* label) {
   }
 }
 
+void Assembler::emit_b(Immediate x) {
+  DCHECK(x.is_int8() || x.is_uint8());
+  uint8_t value = static_cast<uint8_t>(x.x_);
+  *pc_++ = value;
+}
 
 void Assembler::emit_w(const Immediate& x) {
   DCHECK(RelocInfo::IsNone(x.rmode_));