Intrinsify UserTag operations on all architectures

runtime/vm/intrinsifier_ia32.cc

Index: runtime/vm/intrinsifier_ia32.cc
diff --git a/runtime/vm/intrinsifier_ia32.cc b/runtime/vm/intrinsifier_ia32.cc
index 6b4b5d281f0ad52fabeb1222f156ce9a27431e5c..db5cd358d687fdeb8137211d7d076fea507bf483 100644
--- a/runtime/vm/intrinsifier_ia32.cc
+++ b/runtime/vm/intrinsifier_ia32.cc
@@ -1739,6 +1739,53 @@ void Intrinsifier::TwoByteString_equality(Assembler* assembler) {
   StringEquality(assembler, kTwoByteStringCid);
 }
 
+
+// On stack: user tag (+1), return-address (+0).
+void Intrinsifier::UserTag_makeCurrent(Assembler* assembler) {
+  // EBX: Isolate.
+  Isolate* isolate = Isolate::Current();
+  __ leal(EBX, Address::Absolute(reinterpret_cast<uword>(isolate)));

[srdjan, 2014/04/14 15:08:27]

Couldn't you get the address of current_tag here directly? Also for other
architectures.

[zra, 2014/04/14 15:31:29]

At least on ARM and MIPS, I don't think it would save any instructions, and this
way is consistent with how we load object fields in other places.

[Cutch, 2014/04/15 14:36:43]

Done on IA32.

+  // EAX: UserTag.
+  __ movl(EAX, Address(ESP, + 1 * kWordSize));
+  // Set Isolate::current_tag_.
+  __ movl(Address(EBX, Isolate::current_tag_offset()), EAX);
+  // EAX: UserTag's tag.
+  __ movl(EAX, FieldAddress(EAX, UserTag::tag_offset()));
+  // Set Isolate::user_tag_.
+  __ movl(Address(EBX, Isolate::user_tag_offset()), EAX);
+  // Set return value.
+  const Immediate& raw_null =
+      Immediate(reinterpret_cast<int32_t>(Object::null()));
+  __ movl(EAX, raw_null);
+  __ ret();
+}
+
+
+void Intrinsifier::Profiler_getCurrentTag(Assembler* assembler) {
+  // EBX: Isolate.
+  Isolate* isolate = Isolate::Current();
+  __ leal(EBX, Address::Absolute(reinterpret_cast<uword>(isolate)));
+  // Set return value to Isolate::current_tag_.
+  __ movl(EAX, Address(EBX, Isolate::current_tag_offset()));
+  __ ret();
+}
+
+
+void Intrinsifier::Profiler_clearCurrentTag(Assembler* assembler) {
+  // EBX: Isolate.
+  Isolate* isolate = Isolate::Current();
+  __ leal(EBX, Address::Absolute(reinterpret_cast<uword>(isolate)));
+  // Set return value to Isolate::current_tag_.
+  __ movl(EAX, Address(EBX, Isolate::current_tag_offset()));
+  // Clear Isolate::current_tag_.
+  const Immediate& raw_null =
+      Immediate(reinterpret_cast<int32_t>(UserTag::null()));
+  __ movl(Address(EBX, Isolate::current_tag_offset()), raw_null);
+  // Clear Isolate::user_tag_.
+  __ movl(Address(EBX, Isolate::user_tag_offset()), Immediate(0));
+  __ ret();
+}
+
 #undef __
 }  // namespace dart