[ThinLTO] - Simplify code in ThinLTOBitcodeWriter.

Recently introduced convertToDeclaration is very similar
to code used in filterModule function.
Patch reuses it to reduce duplication.

Differential revision: https://reviews.llvm.org/D42971

llvm-svn: 324455

1 files changed, 11 insertions, 37 deletions

diff --git a/llvm/lib/Transforms/IPO/ThinLTOBitcodeWriter.cpp b/llvm/lib/Transforms/IPO/ThinLTOBitcodeWriter.cpp
index d2ce97abdd4..27ef6b3e4b4 100644
--- a/llvm/lib/Transforms/IPO/ThinLTOBitcodeWriter.cpp
+++ b/llvm/lib/Transforms/IPO/ThinLTOBitcodeWriter.cpp
@@ -23,6 +23,7 @@
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Transforms/IPO.h"
 #include "llvm/Transforms/IPO/FunctionAttrs.h"
+#include "llvm/Transforms/IPO/FunctionImport.h"
 #include "llvm/Transforms/Utils/Cloning.h"
 #include "llvm/Transforms/Utils/ModuleUtils.h"
 using namespace llvm;
@@ -169,45 +170,18 @@ void simplifyExternals(Module &M) {
   }
 }
 
-void filterModule(
-    Module *M, function_ref<bool(const GlobalValue *)> ShouldKeepDefinition) {
-  for (Module::alias_iterator I = M->alias_begin(), E = M->alias_end();
-       I != E;) {
-    GlobalAlias *GA = &*I++;
-    if (ShouldKeepDefinition(GA))
-      continue;
-
-    GlobalObject *GO;
-    if (GA->getValueType()->isFunctionTy())
-      GO = Function::Create(cast<FunctionType>(GA->getValueType()),
-                            GlobalValue::ExternalLinkage, "", M);
-    else
-      GO = new GlobalVariable(
-          *M, GA->getValueType(), false, GlobalValue::ExternalLinkage,
-          nullptr, "", nullptr,
-          GA->getThreadLocalMode(), GA->getType()->getAddressSpace());
-    GO->takeName(GA);
-    GA->replaceAllUsesWith(GO);
-    GA->eraseFromParent();
-  }
-
-  for (Function &F : *M) {
-    if (ShouldKeepDefinition(&F))
-      continue;
-
-    F.deleteBody();
-    F.setComdat(nullptr);
-    F.clearMetadata();
-  }
-
-  for (GlobalVariable &GV : M->globals()) {
+static void
+filterModule(Module *M,
+             function_ref<bool(const GlobalValue *)> ShouldKeepDefinition) {
+  auto I = M->global_values().begin();
+  auto E = M->global_values().end();
+  while (I != E) {
+    GlobalValue &GV = *I++;
     if (ShouldKeepDefinition(&GV))
       continue;
-
-    GV.setInitializer(nullptr);
-    GV.setLinkage(GlobalValue::ExternalLinkage);
-    GV.setComdat(nullptr);
-    GV.clearMetadata();
+    if (convertToDeclaration(GV))
+      continue;
+    GV.eraseFromParent();
   }
 }