[llvm] r233092 - DebugInfo: Add MDLocalScope, a legal scope for locals

[Duncan P. N. Exon Smith]

Author: dexonsmith
Date: Tue Mar 24 11:44:29 2015
New Revision: 233092

URL: http://llvm.org/viewvc/llvm-project?rev=233092&view=rev
Log:
DebugInfo: Add MDLocalScope, a legal scope for locals

Add a subclass of `MDScope` to explicitly categorize the legal scopes
for locals -- in particular, scopes that are legal for `MDLocation`,
`MDLexicalBlockBase`, and `MDLocalVariable`.  This provides a convenient
`isa<>` target for the verifier, and eventually I'll be changing the
above classes' `getScope()` to specifically return it.  Currently, its
subclasses are `MDSubprogram`, `MDLexicalBlock`, and
`MDLexicalBlockFile`.

I've gone with `MDLocalScope` for now -- a little ambiguous since it's a
scope *for* locals, not a scope that's local -- but I'm open to more
descriptive names if someone can think of something better.  Regardless,
the code docs should make it clear enough.

Modified:
    llvm/trunk/include/llvm/IR/DebugInfoMetadata.h
    llvm/trunk/include/llvm/IR/Metadata.def

Modified: llvm/trunk/include/llvm/IR/DebugInfoMetadata.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/IR/DebugInfoMetadata.h?rev=233092&r1=233091&r2=233092&view=diff
==============================================================================
--- llvm/trunk/include/llvm/IR/DebugInfoMetadata.h (original)
+++ llvm/trunk/include/llvm/IR/DebugInfoMetadata.h Tue Mar 24 11:44:29 2015
@@ -894,11 +894,31 @@ public:
   }
 };
 
+/// \brief A scope for locals.
+///
+/// A legal scope for lexical blocks, local variables, and debug info
+/// locations.  Subclasses are \a MDSubprogram, \a MDLexicalBlock, and \a
+/// MDLexicalBlockFile.
+class MDLocalScope : public MDScope {
+protected:
+  MDLocalScope(LLVMContext &C, unsigned ID, StorageType Storage, unsigned Tag,
+               ArrayRef<Metadata *> Ops)
+      : MDScope(C, ID, Storage, Tag, Ops) {}
+  ~MDLocalScope() {}
+
+public:
+  static bool classof(const Metadata *MD) {
+    return MD->getMetadataID() == MDSubprogramKind ||
+           MD->getMetadataID() == MDLexicalBlockKind ||
+           MD->getMetadataID() == MDLexicalBlockFileKind;
+  }
+};
+
 /// \brief Subprogram description.
 ///
 /// TODO: Remove DisplayName.  It's always equal to Name.
 /// TODO: Split up flags.
-class MDSubprogram : public MDScope {
+class MDSubprogram : public MDLocalScope {
   friend class LLVMContextImpl;
   friend class MDNode;
 
@@ -915,7 +935,8 @@ class MDSubprogram : public MDScope {
                unsigned ScopeLine, unsigned Virtuality, unsigned VirtualIndex,
                unsigned Flags, bool IsLocalToUnit, bool IsDefinition,
                bool IsOptimized, ArrayRef<Metadata *> Ops)
-      : MDScope(C, MDSubprogramKind, Storage, dwarf::DW_TAG_subprogram, Ops),
+      : MDLocalScope(C, MDSubprogramKind, Storage, dwarf::DW_TAG_subprogram,
+                     Ops),
         Line(Line), ScopeLine(ScopeLine), Virtuality(Virtuality),
         VirtualIndex(VirtualIndex), Flags(Flags), IsLocalToUnit(IsLocalToUnit),
         IsDefinition(IsDefinition), IsOptimized(IsOptimized) {}
@@ -1023,11 +1044,11 @@ public:
   }
 };
 
-class MDLexicalBlockBase : public MDScope {
+class MDLexicalBlockBase : public MDLocalScope {
 protected:
   MDLexicalBlockBase(LLVMContext &C, unsigned ID, StorageType Storage,
                      ArrayRef<Metadata *> Ops)
-      : MDScope(C, ID, Storage, dwarf::DW_TAG_lexical_block, Ops) {}
+      : MDLocalScope(C, ID, Storage, dwarf::DW_TAG_lexical_block, Ops) {}
   ~MDLexicalBlockBase() {}
 
 public:

Modified: llvm/trunk/include/llvm/IR/Metadata.def
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/IR/Metadata.def?rev=233092&r1=233091&r2=233092&view=diff
==============================================================================
--- llvm/trunk/include/llvm/IR/Metadata.def (original)
+++ llvm/trunk/include/llvm/IR/Metadata.def Tue Mar 24 11:44:29 2015
@@ -76,6 +76,7 @@ HANDLE_SPECIALIZED_MDNODE_LEAF(MDComposi
 HANDLE_SPECIALIZED_MDNODE_LEAF(MDSubroutineType)
 HANDLE_SPECIALIZED_MDNODE_LEAF(MDFile)
 HANDLE_SPECIALIZED_MDNODE_LEAF(MDCompileUnit)
+HANDLE_SPECIALIZED_MDNODE_BRANCH(MDLocalScope)
 HANDLE_SPECIALIZED_MDNODE_LEAF(MDSubprogram)
 HANDLE_SPECIALIZED_MDNODE_BRANCH(MDLexicalBlockBase)
 HANDLE_SPECIALIZED_MDNODE_LEAF(MDLexicalBlock)