Add support for __declspec(code_seg("segname"))

This patch uses CodeSegAttr to represent __declspec(code_seg) rather than 
building on the existing support for #pragma code_seg.
The code_seg declspec is applied on functions and classes. This attribute 
enables the placement of code into separate named segments, including compiler-
generated codes and template instantiations.

For more information, please see the following:
https://msdn.microsoft.com/en-us/library/dn636922.aspx

This patch fixes the regression for the support for attribute ((section).
https://github.com/llvm-mirror/clang/commit/746b78de7812bc785fbb5207b788348040b23fa7

Patch by Soumi Manna (Manna)
Differential Revision: https://reviews.llvm.org/D48841

llvm-svn: 337420

1 files changed, 8 insertions, 4 deletions

diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index b412d3083f5..68868708888 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -1387,8 +1387,10 @@ void CodeGenModule::setNonAliasAttributes(GlobalDecl GD,
         F->addAttributes(llvm::AttributeList::FunctionIndex, Attrs);
       }
     }
-
-    if (const SectionAttr *SA = D->getAttr<SectionAttr>())
+    
+    if (const auto *CSA = D->getAttr<CodeSegAttr>())
+      GO->setSection(CSA->getName());
+    else if (const auto *SA = D->getAttr<SectionAttr>())
       GO->setSection(SA->getName());
   }
 
@@ -1485,8 +1487,10 @@ void CodeGenModule::SetFunctionAttributes(GlobalDecl GD, llvm::Function *F,
   setLinkageForGV(F, FD);
   setGVProperties(F, FD);
 
-  if (const SectionAttr *SA = FD->getAttr<SectionAttr>())
-    F->setSection(SA->getName());
+  if (const auto *CSA = FD->getAttr<CodeSegAttr>())
+    F->setSection(CSA->getName());
+  else if (const auto *SA = FD->getAttr<SectionAttr>())
+     F->setSection(SA->getName());
 
   if (FD->isReplaceableGlobalAllocationFunction()) {
     // A replaceable global allocation function does not act like a builtin by