First pass at emitIAS for branches and binding labels

src/IceInstX8632.h

Index: src/IceInstX8632.h
diff --git a/src/IceInstX8632.h b/src/IceInstX8632.h
index 8235d1fe264e284f355e8adbb6d1bc19d1ec573c..baa990d0fbef8c4408d30fd3aa29aa4dcda5145c 100644
--- a/src/IceInstX8632.h
+++ b/src/IceInstX8632.h
@@ -322,14 +322,15 @@ public:
   uint32_t getEmitInstCount() const override { return 0; }
   IceString getName(const Cfg *Func) const;
   void emit(const Cfg *Func) const override;
-  // TODO(jvoung): Filler in.
-  void emitIAS(const Cfg *Func) const override { emit(Func); }
+  void emitIAS(const Cfg *Func) const override;
   void dump(const Cfg *Func) const override;
+  x86::Label *getAsmLabel() const { return &AsmLabel; }
 
 private:
   InstX8632Label(Cfg *Func, TargetX8632 *Target);
   ~InstX8632Label() override {}
   SizeT Number; // used only for unique label string generation
+  mutable x86::Label AsmLabel; // modified by emitIAS.

[Jim Stichnoth, 2014/10/22 18:01:14]

Is the mutable aspect "permanent", or just a stop-gap for textual IAS emission?

[jvoung (off chromium), 2014/10/22 20:43:58]

Unfortunately, it is permanent. I wasn't sure of a good way around this. The
issue is that emitIAS() is "const", but it is at that point when it is
convenient to store the buffer position that the AsmLabel represents, and go
through the queue of forward branch fixups needed and flush that queue.

I could store this Label w/ position and queue externally, like the case for
CfgNode labels, then it would still be const.

[Jim Stichnoth, 2014/10/22 21:50:08]

I think that would be a cleaner approach, maybe a vector parallel to
CfgNodeLabels, or make CfgNodeLabels a vector of tuples.

I just think there shouldn't be mutable or const_cast this early in the
project...

[jvoung (off chromium), 2014/10/23 18:05:27]

Okay I agree it's cleaner. It adds a bit of indirection, but at least on my
machine the performance difference is negligible.

Done.

 };
 
 // Conditional and unconditional branch instruction.
@@ -385,8 +386,7 @@ public:
     return Sum;
   }
   void emit(const Cfg *Func) const override;
-  // TODO(jvoung): Filler in.
-  void emitIAS(const Cfg *Func) const override { emit(Func); }
+  void emitIAS(const Cfg *Func) const override;
   void dump(const Cfg *Func) const override;
   static bool classof(const Inst *Inst) { return isClassof(Inst, Br); }