globaldce. Globaldce was already removing linkonce globals, but globalopt was
not.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158476
91177308-0d34-0410-b5e6-
96231b3b80d8
return Linkage == CommonLinkage;
}
return Linkage == CommonLinkage;
}
+ /// isDiscardableIfUnused - Whether the definition of this global may be
+ /// discarded if it is not used in its compilation unit.
+ static bool isDiscardableIfUnused(LinkageTypes Linkage) {
+ return isLinkOnceLinkage(Linkage) || isLocalLinkage(Linkage);
+ }
+
/// mayBeOverridden - Whether the definition of this global may be replaced
/// by something non-equivalent at link time. For example, if a function has
/// weak linkage then the code defining it may be replaced by different code.
/// mayBeOverridden - Whether the definition of this global may be replaced
/// by something non-equivalent at link time. For example, if a function has
/// weak linkage then the code defining it may be replaced by different code.
void setLinkage(LinkageTypes LT) { Linkage = LT; }
LinkageTypes getLinkage() const { return Linkage; }
void setLinkage(LinkageTypes LT) { Linkage = LT; }
LinkageTypes getLinkage() const { return Linkage; }
+ bool isDiscardableIfUnused() const {
+ return isDiscardableIfUnused(Linkage);
+ }
+
bool mayBeOverridden() const { return mayBeOverridden(Linkage); }
bool isWeakForLinker() const { return isWeakForLinker(Linkage); }
bool mayBeOverridden() const { return mayBeOverridden(Linkage); }
bool isWeakForLinker() const { return isWeakForLinker(Linkage); }
for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) {
Changed |= RemoveUnusedGlobalValue(*I);
// Functions with external linkage are needed if they have a body
for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) {
Changed |= RemoveUnusedGlobalValue(*I);
// Functions with external linkage are needed if they have a body
- if (!I->hasLocalLinkage() && !I->hasLinkOnceLinkage() &&
+ if (!I->isDiscardableIfUnused() &&
!I->isDeclaration() && !I->hasAvailableExternallyLinkage())
GlobalIsNeeded(I);
}
!I->isDeclaration() && !I->hasAvailableExternallyLinkage())
GlobalIsNeeded(I);
}
Changed |= RemoveUnusedGlobalValue(*I);
// Externally visible & appending globals are needed, if they have an
// initializer.
Changed |= RemoveUnusedGlobalValue(*I);
// Externally visible & appending globals are needed, if they have an
// initializer.
- if (!I->hasLocalLinkage() && !I->hasLinkOnceLinkage() &&
+ if (!I->isDiscardableIfUnused() &&
!I->isDeclaration() && !I->hasAvailableExternallyLinkage())
GlobalIsNeeded(I);
}
!I->isDeclaration() && !I->hasAvailableExternallyLinkage())
GlobalIsNeeded(I);
}
I != E; ++I) {
Changed |= RemoveUnusedGlobalValue(*I);
// Externally visible aliases are needed.
I != E; ++I) {
Changed |= RemoveUnusedGlobalValue(*I);
// Externally visible aliases are needed.
- if (!I->hasLocalLinkage() && !I->hasLinkOnceLinkage())
+ if (!I->isDiscardableIfUnused())
/// possible. If we make a change, return true.
bool GlobalOpt::ProcessGlobal(GlobalVariable *GV,
Module::global_iterator &GVI) {
/// possible. If we make a change, return true.
bool GlobalOpt::ProcessGlobal(GlobalVariable *GV,
Module::global_iterator &GVI) {
- if (!GV->hasLocalLinkage())
+ if (!GV->isDiscardableIfUnused())
return false;
// Do more involved optimizations if the global is internal.
return false;
// Do more involved optimizations if the global is internal.
-; RUN: opt < %s -globalopt -S | not grep internal
+; RUN: opt < %s -globalopt -S | FileCheck %s
-@G = internal global i32 123 ; <i32*> [#uses=1]
+@G1 = internal global i32 123 ; <i32*> [#uses=1]
-define void @foo() {
- store i32 1, i32* @G
+; CHECK-NOT: @G1
+; CHECK: @G2
+; CHECK-NOT: @G3
+
+define void @foo1() {
+; CHECK: define void @foo
+; CHECK-NEXT: ret
+ store i32 1, i32* @G1
+ ret void
+}
+
+@G2 = linkonce_odr constant i32 42
+
+define void @foo2() {
+; CHECK: define void @foo2
+; CHECK-NEXT: store
+ store i32 1, i32* @G2
+@G3 = linkonce_odr constant i32 42