Delete dead GlobalAliases.

llvm-svn: 256276
This commit is contained in:
Rafael Espindola 2015-12-22 19:50:22 +00:00
parent 4b0d24c00a
commit 5349d87a69
4 changed files with 14 additions and 4 deletions

View File

@ -2993,10 +2993,17 @@ bool GlobalOpt::OptimizeGlobalAliases(Module &M) {
for (Module::alias_iterator I = M.alias_begin(), E = M.alias_end();
I != E;) {
Module::alias_iterator J = I++;
GlobalAlias *J = &*I++;
// Aliases without names cannot be referenced outside this module.
if (!J->hasName() && !J->isDeclaration() && !J->hasLocalLinkage())
J->setLinkage(GlobalValue::InternalLinkage);
if (deleteIfDead(*J)) {
Changed = true;
continue;
}
// If the aliasee may change at link time, nothing can be done - bail out.
if (J->mayBeOverridden())
continue;

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@ -13,8 +13,8 @@
; CHECK: @weak1 = weak alias void (), void ()* @bar2
@bar4 = private unnamed_addr constant [2 x i8*] zeroinitializer
@foo4 = linkonce_odr unnamed_addr alias i8*, getelementptr inbounds ([2 x i8*], [2 x i8*]* @bar4, i32 0, i32 1)
; CHECK: @foo4 = linkonce_odr unnamed_addr alias i8*, getelementptr inbounds ([2 x i8*], [2 x i8*]* @bar4, i32 0, i32 1)
@foo4 = weak_odr unnamed_addr alias i8*, getelementptr inbounds ([2 x i8*], [2 x i8*]* @bar4, i32 0, i32 1)
; CHECK: @foo4 = weak_odr unnamed_addr alias i8*, getelementptr inbounds ([2 x i8*], [2 x i8*]* @bar4, i32 0, i32 1)
define void @bar2() {
ret void

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@ -1,11 +1,14 @@
; RUN: opt < %s -globalopt -S | FileCheck %s
@G1 = internal global i32 123 ; <i32*> [#uses=1]
@A1 = internal alias i32, i32* @G1
; CHECK-NOT: @G1
; CHECK: @G2
; CHECK-NOT: @G3
; CHECK-NOT: @A1
define void @foo1() {
; CHECK: define void @foo
; CHECK-NEXT: ret

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@ -13,7 +13,7 @@ define i8 @f() norecurse {
}
@H = internal global i32 42
@Halias = internal alias i32, i32* @H
@Halias = alias i32, i32* @H
; @H can't be localized because @Halias uses it, and @Halias can't be converted to an instruction.
define i8 @g() norecurse {