diff options
| -rw-r--r-- | llvm/lib/Transforms/IPO/FunctionImport.cpp | 11 | ||||
| -rw-r--r-- | llvm/test/ThinLTO/X86/Inputs/deadstrip.ll | 5 | ||||
| -rw-r--r-- | llvm/test/ThinLTO/X86/deadstrip.ll | 35 |
3 files changed, 47 insertions, 4 deletions
diff --git a/llvm/lib/Transforms/IPO/FunctionImport.cpp b/llvm/lib/Transforms/IPO/FunctionImport.cpp index 531a7c19e36..1223a23512e 100644 --- a/llvm/lib/Transforms/IPO/FunctionImport.cpp +++ b/llvm/lib/Transforms/IPO/FunctionImport.cpp @@ -777,9 +777,14 @@ void llvm::computeDeadSymbols( VI = updateValueInfoForIndirectCalls(Index, VI); if (!VI) return; - for (auto &S : VI.getSummaryList()) - if (S->isLive()) - return; + + // We need to make sure all variants of the symbol are scanned, alias can + // make one (but not all) alive. + if (llvm::all_of(VI.getSummaryList(), + [](const std::unique_ptr<llvm::GlobalValueSummary> &S) { + return S->isLive(); + })) + return; // We only keep live symbols that are known to be non-prevailing if any are // available_externally, linkonceodr, weakodr. Those symbols are discarded diff --git a/llvm/test/ThinLTO/X86/Inputs/deadstrip.ll b/llvm/test/ThinLTO/X86/Inputs/deadstrip.ll index a9161a31b24..057305ae67e 100644 --- a/llvm/test/ThinLTO/X86/Inputs/deadstrip.ll +++ b/llvm/test/ThinLTO/X86/Inputs/deadstrip.ll @@ -20,3 +20,8 @@ define void @another_dead_func() { call void @dead_func() ret void } + +define linkonce_odr void @linkonceodrfuncwithalias() { +entry: + ret void +} diff --git a/llvm/test/ThinLTO/X86/deadstrip.ll b/llvm/test/ThinLTO/X86/deadstrip.ll index 76dc09e8a9e..257cfafb767 100644 --- a/llvm/test/ThinLTO/X86/deadstrip.ll +++ b/llvm/test/ThinLTO/X86/deadstrip.ll @@ -20,10 +20,14 @@ ; RUN: -r %t1.bc,_live_available_externally_func,l \ ; RUN: -r %t1.bc,_live_linkonce_odr_func,l \ ; RUN: -r %t1.bc,_live_weak_odr_func,l \ +; RUN: -r %t1.bc,_linkonceodralias,pl \ +; RUN: -r %t1.bc,_linkonceodrfuncwithalias,l \ +; RUN: -r %t1.bc,_linkonceodrfuncwithalias_caller,pl \ ; RUN: -r %t2.bc,_baz,pl \ ; RUN: -r %t2.bc,_boo,pl \ ; RUN: -r %t2.bc,_dead_func,l \ ; RUN: -r %t2.bc,_another_dead_func,pl \ +; RUN: -r %t2.bc,_linkonceodrfuncwithalias,pl \ ; RUN: -thinlto-threads=1 \ ; RUN: -debug-only=function-import 2>&1 | FileCheck %s --check-prefix=DEBUG --check-prefix=STATS ; RUN: llvm-dis < %t.out.1.3.import.bc | FileCheck %s --check-prefix=LTO2 @@ -71,6 +75,11 @@ ; llvm.global_ctors ; CHECK2: define void @boo() ; LTO2-CHECK2: define dso_local void @boo() + +; Make sure we keep @linkonceodrfuncwithalias in Input/deadstrip.ll alive as it +; is reachable from @main. +; LTO2-CHECK2: define weak_odr dso_local void @linkonceodrfuncwithalias() { + ; We should have eventually removed @baz since it was internalized and unused ; CHECK2-NM-NOT: _baz @@ -105,10 +114,14 @@ ; RUN: -r %t1.bc,_live_available_externally_func,l \ ; RUN: -r %t1.bc,_live_linkonce_odr_func,l \ ; RUN: -r %t1.bc,_live_weak_odr_func,l \ +; RUN: -r %t1.bc,_linkonceodralias,pl \ +; RUN: -r %t1.bc,_linkonceodrfuncwithalias,l \ +; RUN: -r %t1.bc,_linkonceodrfuncwithalias_caller,pl \ ; RUN: -r %t3.bc,_baz,pl \ ; RUN: -r %t3.bc,_boo,pl \ ; RUN: -r %t3.bc,_dead_func,l \ -; RUN: -r %t3.bc,_another_dead_func,pl +; RUN: -r %t3.bc,_another_dead_func,pl \ +; RUN: -r %t3.bc,_linkonceodrfuncwithalias,pl ; RUN: llvm-dis < %t4.out.1.3.import.bc | FileCheck %s --check-prefix=CHECK-NOTDEAD ; RUN: llvm-nm %t4.out.0 | FileCheck %s --check-prefix=CHECK-NM-NOTDEAD @@ -163,11 +176,31 @@ define available_externally void @live_available_externally_func() { ret void } +; This alias will set its base object in this file (linkonceodrfuncwithalias) +; alive. +; We want to make sure the @linkonceodrfuncwithalias copy in Input/deadstrip.ll +; is also scanned when computing reachability. +@linkonceodralias = linkonce_odr alias void (), void ()* @linkonceodrfuncwithalias + +define linkonce_odr void @linkonceodrfuncwithalias() { +entry: + ret void +} + +define void @linkonceodrfuncwithalias_caller() { +entry: + call void @linkonceodrfuncwithalias() + ret void +} + + define void @main() { call void @bar() call void @bar_internal() call void @live_linkonce_odr_func() call void @live_weak_odr_func() call void @live_available_externally_func() + call void @linkonceodrfuncwithalias_caller() + call void @linkonceodralias() ret void } |
