[PATCH] Expose the NamedOnly flag in IRMover

[Ben Karel via llvm-commits]

In the 4.0 cycle, the NamedOnly flag in IRMover.cpp was changed from true
to false. This wound up breaking my out-of-tree compiler frontend.

The attached patch threads through the NamedOnly flag from IRMover to
Linker and adds a new flag enum value. Thus, the behavior of existing code
remains the same, but linker clients can override the NamedOnly behavior as
needed.

I added new constructors to IRMover and Linker, rather than changing the
signature of the existing constructors, to minimize changes in the rest of
the codebase.

I originally implemented the patch against the 4.0 codebase. I've compiled
it against trunk but didn't bother running any tests... I'm hoping that
it's small enough that a mainline LLVM dev can fold the patch (with fixes
for any style nits ;-)) into their compile-test cycle if desired.

Cheers!
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20170525/2d1a71da/attachment.html>
-------------- next part --------------
Index: include/llvm/Linker/IRMover.h
===================================================================
--- include/llvm/Linker/IRMover.h	(revision 303835)
+++ include/llvm/Linker/IRMover.h	(working copy)
@@ -61,6 +61,7 @@
   };

   IRMover(Module &M);
+  IRMover(Module &M, bool OnlyNamedTypes);

   typedef std::function<void(GlobalValue &)> ValueAdder;

Index: include/llvm/Linker/Linker.h
===================================================================
--- include/llvm/Linker/Linker.h	(revision 303835)
+++ include/llvm/Linker/Linker.h	(working copy)
@@ -30,9 +30,11 @@
     None = 0,
     OverrideFromSrc = (1 << 0),
     LinkOnlyNeeded = (1 << 1),
+    DontLinkUnnamedTypes = (1 << 2),
   };

   Linker(Module &M);
+  Linker(Module &M, unsigned Flags);

   /// \brief Link \p Src into the composite.
   ///
Index: lib/Linker/IRMover.cpp
===================================================================
--- lib/Linker/IRMover.cpp	(revision 303835)
+++ lib/Linker/IRMover.cpp	(working copy)
@@ -1411,9 +1411,10 @@
   return I == NonOpaqueStructTypes.end() ? false : *I == Ty;
 }

-IRMover::IRMover(Module &M) : Composite(M) {
+IRMover::IRMover(Module &M) : IRMover::IRMover(M, false) {}
+IRMover::IRMover(Module &M, bool OnlyNamedTypes) : Composite(M) {
   TypeFinder StructTypes;
-  StructTypes.run(M, /* OnlyNamed */ false);
+  StructTypes.run(M, OnlyNamedTypes);
   for (StructType *Ty : StructTypes) {
     if (Ty->isOpaque())
       IdentifiedStructTypes.addOpaque(Ty);
Index: lib/Linker/LinkModules.cpp
===================================================================
--- lib/Linker/LinkModules.cpp	(revision 303835)
+++ lib/Linker/LinkModules.cpp	(working copy)
@@ -561,6 +561,9 @@

 Linker::Linker(Module &M) : Mover(M) {}

+Linker::Linker(Module &M, unsigned Flags) :
+  Mover(M, (Flags & DontLinkUnnamedTypes) != 0) {}
+
 bool Linker::linkInModule(
     std::unique_ptr<Module> Src, unsigned Flags,
     std::function<void(Module &, const StringSet<> &)> InternalizeCallback) {
@@ -581,7 +584,7 @@
 bool Linker::linkModules(
     Module &Dest, std::unique_ptr<Module> Src, unsigned Flags,
     std::function<void(Module &, const StringSet<> &)> InternalizeCallback) {
-  Linker L(Dest);
+  Linker L(Dest, Flags);
   return L.linkInModule(std::move(Src), Flags, std::move(InternalizeCallback));
 }