From 4474958d3a97dede2caa0920f7c4a4dc7aac57d3 Mon Sep 17 00:00:00 2001 From: Sami Tolvanen <samitolvanen@google.com> Date: Tue, 22 Jun 2021 09:28:31 -0700 Subject: [PATCH] ThinLTO: Fix inline assembly references to static functions with CFI Create an internal alias with the original name for static functions that are renamed in promoteInternals to avoid breaking inline assembly references to them. Link: https://github.com/ClangBuiltLinux/linux/issues/1354 Reviewed By: pcc Differential Revision: https://reviews.llvm.org/D104058 --- .../Transforms/IPO/ThinLTOBitcodeWriter.cpp | 9 +++++++++ .../cfi-icall-static-inline-asm.ll | 19 +++++++++++++++++++ 2 files changed, 28 insertions(+) create mode 100644 llvm/test/Transforms/ThinLTOBitcodeWriter/cfi-icall-static-inline-asm.ll diff --git a/llvm/lib/Transforms/IPO/ThinLTOBitcodeWriter.cpp b/llvm/lib/Transforms/IPO/ThinLTOBitcodeWriter.cpp index 37329b489555..255b1f7f4357 100644 --- a/llvm/lib/Transforms/IPO/ThinLTOBitcodeWriter.cpp +++ b/llvm/lib/Transforms/IPO/ThinLTOBitcodeWriter.cpp @@ -69,6 +69,15 @@ void promoteInternals(Module &ExportM, Module &ImportM, StringRef ModuleId, ImportGV->setName(NewName); ImportGV->setVisibility(GlobalValue::HiddenVisibility); } + + if (Function *F = dyn_cast<Function>(&ExportGV)) { + // Create a local alias with the original name to avoid breaking + // references from inline assembly. + GlobalAlias *A = + GlobalAlias::create(F->getValueType(), F->getAddressSpace(), + GlobalValue::InternalLinkage, Name, F, &ExportM); + appendToCompilerUsed(ExportM, A); + } } if (!RenamedComdats.empty()) diff --git a/llvm/test/Transforms/ThinLTOBitcodeWriter/cfi-icall-static-inline-asm.ll b/llvm/test/Transforms/ThinLTOBitcodeWriter/cfi-icall-static-inline-asm.ll new file mode 100644 index 000000000000..70f5322faa52 --- /dev/null +++ b/llvm/test/Transforms/ThinLTOBitcodeWriter/cfi-icall-static-inline-asm.ll @@ -0,0 +1,19 @@ +; RUN: opt -thinlto-bc -thinlto-split-lto-unit -o - %s | llvm-modextract -b -n 0 -o - | llvm-dis | FileCheck %s + +; CHECK: @a = internal alias {{.*}}@a.[[HASH:[0-9a-f]+]] + +define void @b() { + %f = alloca void ()*, align 8 + ; CHECK: store{{.*}} @a.[[HASH]],{{.*}} %f + store void ()* @a, void ()** %f, align 8 + ; CHECK: %1 = call void ()* asm sideeffect "leaq a(%rip) + %1 = call void ()* asm sideeffect "leaq a(%rip), $0\0A\09", "=r,~{dirflag},~{fpsr},~{flags}"() + ret void +} + +; CHECK: define{{.*}} @a.[[HASH]](){{.*}} !type +define internal void @a() !type !0 { + ret void +} + +!0 = !{i64 0, !"typeid1"}