Backport a fix addressing miscompliation related to TLS

this change backports a commit from upstream's release/18.x branch
to address a miscompliation related to TLS. the fix addresses the
issue where TLS variables could fail to initialize after the
globalopt pass.

this change has been backported to the release/18.x branch, but
since LLVM 17.0.6 does not receive any more patches, we need to
backport it in downstream.

Signed-off-by: Kefu Chai <tchaikov@gmail.com>
This commit is contained in:
Kefu Chai 2024-05-18 07:23:15 +08:00
parent 79d4892286
commit 528cead504
2 changed files with 104 additions and 1 deletions

View file

@ -0,0 +1,97 @@
From 3d0752b9492efd60e85aedec79676596af6fb4f8 Mon Sep 17 00:00:00 2001
From: DianQK <dianqk@dianqk.net>
Date: Fri, 17 May 2024 05:51:49 +0800
Subject: [PATCH] [GlobalOpt] Don't replace aliasee with alias that has weak
linkage (#91483)
Fixes #91312.
Don't perform the transform if the alias may be replaced at link time.
(cherry picked from commit c79690040acf5bb3d857558b0878db47f7f23dc3)
---
llvm/lib/Transforms/IPO/GlobalOpt.cpp | 3 ++
llvm/test/Transforms/GlobalOpt/alias-weak.ll | 57 ++++++++++++++++++++
2 files changed, 60 insertions(+)
create mode 100644 llvm/test/Transforms/GlobalOpt/alias-weak.ll
diff --git a/llvm/lib/Transforms/IPO/GlobalOpt.cpp b/llvm/lib/Transforms/IPO/GlobalOpt.cpp
index 951372adcfa9..619b3f612f25 100644
--- a/llvm/lib/Transforms/IPO/GlobalOpt.cpp
+++ b/llvm/lib/Transforms/IPO/GlobalOpt.cpp
@@ -2212,6 +2212,9 @@ static bool mayHaveOtherReferences(GlobalValue &GV, const LLVMUsed &U) {
static bool hasUsesToReplace(GlobalAlias &GA, const LLVMUsed &U,
bool &RenameTarget) {
+ if (GA.isWeakForLinker())
+ return false;
+
RenameTarget = false;
bool Ret = false;
if (hasUseOtherThanLLVMUsed(GA, U))
diff --git a/llvm/test/Transforms/GlobalOpt/alias-weak.ll b/llvm/test/Transforms/GlobalOpt/alias-weak.ll
new file mode 100644
index 000000000000..aec2a56313b1
--- /dev/null
+++ b/llvm/test/Transforms/GlobalOpt/alias-weak.ll
@@ -0,0 +1,57 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals all --include-generated-funcs --version 4
+; RUN: opt < %s -passes=globalopt -S | FileCheck %s
+
+@f1_alias = linkonce_odr hidden alias void (), ptr @f1
+@f2_alias = linkonce_odr hidden alias void (), ptr @f2
+
+define void @foo() {
+ call void @f1_alias()
+ ret void
+}
+
+define void @bar() {
+ call void @f1()
+ ret void
+}
+
+define void @baz() {
+ call void @f2_alias()
+ ret void
+}
+
+; We cannot use `f1_alias` to replace `f1` because they are both in use
+; and `f1_alias` could be replaced at link time.
+define internal void @f1() {
+ ret void
+}
+
+; FIXME: We can use `f2_alias` to replace `f2` because `b2` is not in use.
+define internal void @f2() {
+ ret void
+}
+;.
+; CHECK: @f1_alias = linkonce_odr hidden alias void (), ptr @f1
+; CHECK: @f2_alias = linkonce_odr hidden alias void (), ptr @f2
+;.
+; CHECK-LABEL: define void @foo() local_unnamed_addr {
+; CHECK-NEXT: call void @f1_alias()
+; CHECK-NEXT: ret void
+;
+;
+; CHECK-LABEL: define void @bar() local_unnamed_addr {
+; CHECK-NEXT: call void @f1()
+; CHECK-NEXT: ret void
+;
+;
+; CHECK-LABEL: define void @baz() local_unnamed_addr {
+; CHECK-NEXT: call void @f2_alias()
+; CHECK-NEXT: ret void
+;
+;
+; CHECK-LABEL: define internal void @f1() {
+; CHECK-NEXT: ret void
+;
+;
+; CHECK-LABEL: define internal void @f2() {
+; CHECK-NEXT: ret void
+;
--
2.45.1

View file

@ -93,7 +93,7 @@
Name: %{pkg_name} Name: %{pkg_name}
Version: %{maj_ver}.%{min_ver}.%{patch_ver}%{?rc_ver:~rc%{rc_ver}}%{?llvm_snapshot_version_suffix:~%{llvm_snapshot_version_suffix}} Version: %{maj_ver}.%{min_ver}.%{patch_ver}%{?rc_ver:~rc%{rc_ver}}%{?llvm_snapshot_version_suffix:~%{llvm_snapshot_version_suffix}}
Release: 3%{?dist} Release: 4%{?dist}
Summary: The Low Level Virtual Machine Summary: The Low Level Virtual Machine
License: Apache-2.0 WITH LLVM-exception OR NCSA License: Apache-2.0 WITH LLVM-exception OR NCSA
@ -115,6 +115,9 @@ Source6: release-keys.asc
# Backport of https://reviews.llvm.org/D156485 for rhbz#2262260. # Backport of https://reviews.llvm.org/D156485 for rhbz#2262260.
Patch0: 0001-PEI-Don-t-zero-out-noreg-operands.patch Patch0: 0001-PEI-Don-t-zero-out-noreg-operands.patch
# https://github.com/llvm/llvm-project/commit/3d0752b9492efd60e85aedec79676596af6fb4f8
# This patch will be in 18.1.6
Patch1: 0001-GlobalOpt-Don-t-replace-aliasee-with-alias-that-has-.patch
# RHEL-specific patch to avoid unwanted recommonmark dep # RHEL-specific patch to avoid unwanted recommonmark dep
Patch101: 0101-Deactivate-markdown-doc.patch Patch101: 0101-Deactivate-markdown-doc.patch
@ -614,6 +617,9 @@ fi
%changelog %changelog
%{?llvm_snapshot_changelog_entry} %{?llvm_snapshot_changelog_entry}
* Thu May 30 2024 Kefu Chai <tchaikov@fedoraproject.org> - 17.0.6-4
- Backport fix for https://github.com/llvm/llvm-project/issues/91312
* Thu Feb 01 2024 Nikita Popov <npopov@redhat.com> - 17.0.6-3 * Thu Feb 01 2024 Nikita Popov <npopov@redhat.com> - 17.0.6-3
- Fix crash with -fzero-call-used-regs (rhbz#2262260) - Fix crash with -fzero-call-used-regs (rhbz#2262260)