From d7bb2de6712dc5cf32f6a6c5a9c2bfeaa4224a45 Mon Sep 17 00:00:00 2001 From: Rafael Espindola Date: Wed, 23 Mar 2016 21:16:33 +0000 Subject: [PATCH] Fix logic for which symbols to keep with comdats. If a comdat is dropped, all symbols in it are dropped. If a comdat is kept, the symbols survive to pass regular symbol resolution. With this patch we do that for all global symbols. The added test is a copy of test/tools/gold/X86/comdat.ll that we now pass. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@264192 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Linker/LinkModules.cpp | 8 ++--- test/Linker/Inputs/comdat16.ll | 26 ++++++++++++++++ test/Linker/comdat16.ll | 63 +++++++++++++++++++++++++++++++++++++++ test/Linker/constructor-comdat.ll | 5 +++- 4 files changed, 97 insertions(+), 5 deletions(-) create mode 100644 test/Linker/Inputs/comdat16.ll create mode 100644 test/Linker/comdat16.ll diff --git a/lib/Linker/LinkModules.cpp b/lib/Linker/LinkModules.cpp index 8eeccb369df..d3c3ea34e6d 100644 --- a/lib/Linker/LinkModules.cpp +++ b/lib/Linker/LinkModules.cpp @@ -422,9 +422,8 @@ bool ModuleLinker::linkIfNeeded(GlobalValue &GV) { bool LinkFromSrc; Comdat::SelectionKind SK; std::tie(SK, LinkFromSrc) = ComdatsChosen[SC]; - if (LinkFromSrc) - ValuesToLink.insert(&GV); - return false; + if (!LinkFromSrc) + return false; } bool LinkFromSrc = true; @@ -565,7 +564,8 @@ bool ModuleLinker::run() { if (!SC) continue; for (GlobalValue *GV2 : ComdatMembers[SC]) - ValuesToLink.insert(GV2); + if (GV2->hasInternalLinkage()) + ValuesToLink.insert(GV2); } if (shouldInternalizeLinkedSymbols()) { diff --git a/test/Linker/Inputs/comdat16.ll b/test/Linker/Inputs/comdat16.ll new file mode 100644 index 00000000000..7644e0e1ce9 --- /dev/null +++ b/test/Linker/Inputs/comdat16.ll @@ -0,0 +1,26 @@ +$c2 = comdat any +$c1 = comdat any + +; This is only present in this file. The linker will keep $c1 from the first +; file and this will be undefined. +@will_be_undefined = global i32 1, comdat($c1) +@use = global i32* @will_be_undefined + +@v1 = weak_odr global i32 41, comdat($c2) +define weak_odr protected i32 @f1(i8* %this) comdat($c2) { +bb20: + store i8* %this, i8** null + br label %bb21 +bb21: + ret i32 41 +} + +@r21 = global i32* @v1 +@r22 = global i32(i8*)* @f1 + +@a21 = alias i32, i32* @v1 +@a22 = alias i16, bitcast (i32* @v1 to i16*) + +@a23 = alias i32(i8*), i32(i8*)* @f1 +@a24 = alias i16, bitcast (i32(i8*)* @f1 to i16*) +@a25 = alias i16, i16* @a24 diff --git a/test/Linker/comdat16.ll b/test/Linker/comdat16.ll new file mode 100644 index 00000000000..47b14220785 --- /dev/null +++ b/test/Linker/comdat16.ll @@ -0,0 +1,63 @@ +; RUN: llvm-link -S -o - %s %p/Inputs/comdat16.ll | FileCheck %s + +$c1 = comdat any + +@v1 = weak_odr global i32 42, comdat($c1) +define weak_odr i32 @f1(i8*) comdat($c1) { +bb10: + br label %bb11 +bb11: + ret i32 42 +} + +@r11 = global i32* @v1 +@r12 = global i32 (i8*)* @f1 + +@a11 = alias i32, i32* @v1 +@a12 = alias i16, bitcast (i32* @v1 to i16*) + +@a13 = alias i32 (i8*), i32 (i8*)* @f1 +@a14 = alias i16, bitcast (i32 (i8*)* @f1 to i16*) +@a15 = alias i16, i16* @a14 + +; CHECK: $c1 = comdat any +; CHECK: $c2 = comdat any + +; CHECK-DAG: @will_be_undefined = external global i32 + +; CHECK-DAG: @v1 = weak_odr global i32 42, comdat($c1) + +; CHECK-DAG: @r11 = global i32* @v1{{$}} +; CHECK-DAG: @r12 = global i32 (i8*)* @f1{{$}} + +; CHECK-DAG: @r21 = global i32* @v1{{$}} +; CHECK-DAG: @r22 = global i32 (i8*)* @f1{{$}} + +; CHECK-DAG: @v1.1 = internal global i32 41, comdat($c2) + +; CHECK-DAG: @a11 = alias i32, i32* @v1{{$}} +; CHECK-DAG: @a12 = alias i16, bitcast (i32* @v1 to i16*) + +; CHECK-DAG: @a13 = alias i32 (i8*), i32 (i8*)* @f1{{$}} +; CHECK-DAG: @a14 = alias i16, bitcast (i32 (i8*)* @f1 to i16*) + +; CHECK-DAG: @a21 = alias i32, i32* @v1.1{{$}} +; CHECK-DAG: @a22 = alias i16, bitcast (i32* @v1.1 to i16*) + +; CHECK-DAG: @a23 = alias i32 (i8*), i32 (i8*)* @f1.2{{$}} +; CHECK-DAG: @a24 = alias i16, bitcast (i32 (i8*)* @f1.2 to i16*) + +; CHECK: define weak_odr protected i32 @f1(i8*) comdat($c1) { +; CHECK-NEXT: bb10: +; CHECK-NEXT: br label %bb11{{$}} +; CHECK: bb11: +; CHECK-NEXT: ret i32 42 +; CHECK-NEXT: } + +; CHECK: define internal i32 @f1.2(i8* %this) comdat($c2) { +; CHECK-NEXT: bb20: +; CHECK-NEXT: store i8* %this, i8** null +; CHECK-NEXT: br label %bb21 +; CHECK: bb21: +; CHECK-NEXT: ret i32 41 +; CHECK-NEXT: } diff --git a/test/Linker/constructor-comdat.ll b/test/Linker/constructor-comdat.ll index e62990157a9..0e8fc440f20 100644 --- a/test/Linker/constructor-comdat.ll +++ b/test/Linker/constructor-comdat.ll @@ -1,13 +1,16 @@ ; RUN: llvm-link %s %p/Inputs/constructor-comdat.ll -S -o - 2>&1 | FileCheck %s -; RUN: llvm-link %p/Inputs/constructor-comdat.ll %s -S -o - 2>&1 | FileCheck %s +; RUN: llvm-link %p/Inputs/constructor-comdat.ll %s -S -o - 2>&1 | FileCheck --check-prefix=NOCOMDAT %s $_ZN3fooIiEC5Ev = comdat any ; CHECK: $_ZN3fooIiEC5Ev = comdat any +; NOCOMDAT-NOT: comdat @_ZN3fooIiEC1Ev = weak_odr alias void (), void ()* @_ZN3fooIiEC2Ev ; CHECK: @_ZN3fooIiEC1Ev = weak_odr alias void (), void ()* @_ZN3fooIiEC2Ev +; NOCOMDAT-DAG: define weak_odr void @_ZN3fooIiEC1Ev() { ; CHECK: define weak_odr void @_ZN3fooIiEC2Ev() comdat($_ZN3fooIiEC5Ev) { +; NOCOMDAT-DAG: define weak_odr void @_ZN3fooIiEC2Ev() { define weak_odr void @_ZN3fooIiEC2Ev() comdat($_ZN3fooIiEC5Ev) { ret void } -- 2.11.0