Clarify which type "Label" refers to (generic vs X86)

src/IceAssembler.h

Index: src/IceAssembler.h
diff --git a/src/IceAssembler.h b/src/IceAssembler.h
index d53a3be2b4e22bc0fd36c6f6ad116d3cd8517bee..82eb95ca7f92777335df66792b977c235ac42aef 100644
--- a/src/IceAssembler.h
+++ b/src/IceAssembler.h
@@ -30,17 +30,17 @@
 
 namespace Ice {
 
-/// A Label can be in one of three states:
+/// A LabelBase can be in one of three states:
 ///  - Unused.
 ///  - Linked, unplaced and tracking the position of branches to the label.
 ///  - Bound, placed and tracking its position.
-class Label {
-  Label(const Label &) = delete;
-  Label &operator=(const Label &) = delete;
+class LabelBase {

[ascull, 2015/07/31 20:54:54]

Given that ARM and MIPS won't extend this is and that it is not abstract it
would make more sense for this to stay being called Label and for the name to
change in the specialization.

[jvoung (off chromium), 2015/08/03 17:19:21]

Hmm good point about "Base"... ARM and MIPS don't distinguish between Near/Far
so it didn't need the extension.

I wasn't too excited about changing X86 to something other than "Label" if ARM
and MIPS were assemblers/assembler tests were going to simply use "Label" in
their namespace. Then the assemblers would have more similarity, modulo the
namespace. Otherwise, if folks feel strongly and do want to call the X86 version
something else, I'd prefer to come up with a name before I go off and change a
bunch of files =)

For now, I've reverted LabelBase to Label, kept the x86 version as
Ice::X86Internal::Label, and kept the split of getCfgNodeLabel() vs
getOrCreateCfgNodeLabel(), since sometimes getOrCreateCfgNodeLabel()'s return
type is expected to be Ice::X86Internal::Label instead of Ice::Label, while
getCfgNodeLabel() return type is expected to be Ice::Label.

+  LabelBase(const LabelBase &) = delete;
+  LabelBase &operator=(const LabelBase &) = delete;
 
 public:
-  Label() = default;
-  ~Label() = default;
+  LabelBase() = default;
+  ~LabelBase() = default;
 
   virtual void finalCheck() const {
     // Assert if label is being destroyed with unresolved branches pending.
@@ -249,7 +249,7 @@ public:
   virtual llvm::ArrayRef<uint8_t> getNonExecBundlePadding() const = 0;
 
   /// Get the label for a CfgNode.
-  virtual Label *getOrCreateCfgNodeLabel(SizeT NodeNumber) = 0;
+  virtual LabelBase *getCfgNodeLabel(SizeT NodeNumber) = 0;
   /// Mark the current text location as the start of a CFG node
   /// (represented by NodeNumber).
   virtual void bindCfgNodeLabel(SizeT NodeNumber) = 0;