#include <algorithm>
using namespace llvm;
+/// Make sure GV is visible from both modules. Delete is true if it is
+/// being deleted from this module.
+/// This also makes sure GV cannot be dropped so that references from
+/// the split module remain valid.
+static void makeVisible(GlobalValue &GV, bool Delete) {
+ bool Local = GV.hasLocalLinkage();
+ if (Local)
+ GV.setVisibility(GlobalValue::HiddenVisibility);
+
+ if (Local || Delete) {
+ GV.setLinkage(GlobalValue::ExternalLinkage);
+ return;
+ }
+
+ if (!GV.hasLinkOnceLinkage()) {
+ assert(!GV.isDiscardableIfUnused());
+ return;
+ }
+
+ // Map linkonce* to weak* so that llvm doesn't drop this GV.
+ switch(GV.getLinkage()) {
+ default:
+ llvm_unreachable("Unexpected linkage");
+ case GlobalValue::LinkOnceAnyLinkage:
+ GV.setLinkage(GlobalValue::WeakAnyLinkage);
+ return;
+ case GlobalValue::LinkOnceODRLinkage:
+ GV.setLinkage(GlobalValue::WeakODRLinkage);
+ return;
+ }
+}
+
namespace {
/// @brief A pass to extract specific functions and their dependencies.
class GVExtractorPass : public ModulePass {
continue;
}
- bool Local = I->isDiscardableIfUnused();
- if (Local)
- I->setVisibility(GlobalValue::HiddenVisibility);
-
- if (Local || Delete)
- I->setLinkage(GlobalValue::ExternalLinkage);
+ makeVisible(*I, Delete);
if (Delete)
I->setInitializer(0);
continue;
}
- bool Local = I->isDiscardableIfUnused();
- if (Local)
- I->setVisibility(GlobalValue::HiddenVisibility);
-
- if (Local || Delete)
- I->setLinkage(GlobalValue::ExternalLinkage);
+ makeVisible(*I, Delete);
if (Delete)
I->deleteBody();
Module::alias_iterator CurI = I;
++I;
- if (CurI->isDiscardableIfUnused()) {
- CurI->setVisibility(GlobalValue::HiddenVisibility);
- CurI->setLinkage(GlobalValue::ExternalLinkage);
- }
+ bool Delete = deleteStuff == (bool)Named.count(CurI);
+ makeVisible(*CurI, Delete);
- if (deleteStuff == (bool)Named.count(CurI)) {
+ if (Delete) {
Type *Ty = CurI->getType()->getElementType();
CurI->removeFromParent();
; RUN: llvm-extract -func foo -S < %s | FileCheck %s
; RUN: llvm-extract -delete -func foo -S < %s | FileCheck --check-prefix=DELETE %s
-; Test that we don't convert weak_odr to external definitions.
+; Test that linkonce definitions are mapped to weak so that they are not
+; dropped.
-; CHECK: @bar = external hidden global i32
-; CHECK: define hidden i32* @foo() {
+; CHECK: @bar = external global i32
+; CHECK: define weak i32* @foo() {
; CHECK-NEXT: ret i32* @bar
; CHECK-NEXT: }
-; DELETE: @bar = hidden global i32 42
-; DELETE: declare hidden i32* @foo()
+; DELETE: @bar = weak global i32 42
+; DELETE: declare i32* @foo()
@bar = linkonce global i32 42