[IR] Allow attributes with global variables

This patch extends llvm-ir to allow attributes to be set on global variables.
An RFC was sent out earlier by my colleague James Molloy: http://lists.llvm.org/pipermail/cfe-dev/2017-March/053100.html
A key part of that proposal was to extend LLVM-IR to carry attributes on global variables.
This generic feature could be useful for multiple purposes.
In our present context, it would be useful to carry user specified sections for bss/rodata/data.

Reviewed by: Jonathan Roelofs, Reid Kleckner
Differential Revision: https://reviews.llvm.org/D32009



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@302794 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 16 insertions, 2 deletions

diff --git a/lib/AsmParser/LLParser.cpp b/lib/AsmParser/LLParser.cpp
index 97a567565b4..d7602c83435 100644
--- a/lib/AsmParser/LLParser.cpp
+++ b/lib/AsmParser/LLParser.cpp
@@ -162,6 +162,10 @@ bool LLParser::ValidateEndOfModule() {
       AS = AS.addAttributes(Context, AttributeList::FunctionIndex,
                             AttributeSet::get(Context, FnAttrs));
       II->setAttributes(AS);
+    } else if (auto *GV = dyn_cast<GlobalVariable>(V)) {
+      AttrBuilder Attrs(GV->getAttributes());
+      Attrs.merge(B);
+      GV->setAttributes(AttributeSet::get(Context,Attrs));
     } else {
       llvm_unreachable("invalid object with forward attribute group reference");
     }
@@ -832,10 +836,10 @@ bool LLParser::parseIndirectSymbol(
 /// ParseGlobal
 ///   ::= GlobalVar '=' OptionalLinkage OptionalVisibility OptionalDLLStorageClass
 ///       OptionalThreadLocal OptionalUnnamedAddr OptionalAddrSpace
-///       OptionalExternallyInitialized GlobalType Type Const
+///       OptionalExternallyInitialized GlobalType Type Const OptionalAttrs
 ///   ::= OptionalLinkage OptionalVisibility OptionalDLLStorageClass
 ///       OptionalThreadLocal OptionalUnnamedAddr OptionalAddrSpace
-///       OptionalExternallyInitialized GlobalType Type Const
+///       OptionalExternallyInitialized GlobalType Type Const OptionalAttrs
 ///
 /// Everything up to and including OptionalUnnamedAddr has been parsed
 /// already.
@@ -950,6 +954,16 @@ bool LLParser::ParseGlobal(const std::string &Name, LocTy NameLoc,
     }
   }
 
+  AttrBuilder Attrs;
+  LocTy BuiltinLoc;
+  std::vector<unsigned> FwdRefAttrGrps;
+  if (ParseFnAttributeValuePairs(Attrs, FwdRefAttrGrps, false, BuiltinLoc))
+    return true;
+  if (Attrs.hasAttributes() || !FwdRefAttrGrps.empty()) {
+    GV->setAttributes(AttributeSet::get(Context, Attrs));
+    ForwardRefAttrGroups[GV] = FwdRefAttrGrps;
+  }
+
   return false;
 }