Revert #67745 "[asan] Ensure __asan_register_elf_globals is called in COMDAT asan.module_ctor (#67745)"
This reverts commit 1a4b9b6f73391d94f4f96cc964cbf89cfdd59b5b.
When getUniqueModuleId(&M) is empty, we may add comdat to internal constants
like $.str, causing spurious `error: relocation refers to a symbol in a
discarded section` lld errors.
GitOrigin-RevId: 5d87665de956eaa237def9c7a35c449e71629302
diff --git a/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/lib/Transforms/Instrumentation/AddressSanitizer.cpp
index 6ec592f..bde5fba 100644
--- a/lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ b/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -819,7 +819,7 @@
private:
void initializeCallbacks(Module &M);
- void InstrumentGlobals(IRBuilder<> &IRB, Module &M, bool *CtorComdat);
+ bool InstrumentGlobals(IRBuilder<> &IRB, Module &M, bool *CtorComdat);
void InstrumentGlobalsCOFF(IRBuilder<> &IRB, Module &M,
ArrayRef<GlobalVariable *> ExtendedGlobals,
ArrayRef<Constant *> MetadataInitializers);
@@ -2237,7 +2237,7 @@
// We also need to unregister globals at the end, e.g., when a shared library
// gets closed.
- if (DestructorKind != AsanDtorKind::None && !MetadataGlobals.empty()) {
+ if (DestructorKind != AsanDtorKind::None) {
IRBuilder<> IrbDtor(CreateAsanModuleDtor(M));
IrbDtor.CreateCall(AsanUnregisterElfGlobals,
{IRB.CreatePointerCast(RegisteredFlag, IntptrTy),
@@ -2343,8 +2343,10 @@
// redzones and inserts this function into llvm.global_ctors.
// Sets *CtorComdat to true if the global registration code emitted into the
// asan constructor is comdat-compatible.
-void ModuleAddressSanitizer::InstrumentGlobals(IRBuilder<> &IRB, Module &M,
+bool ModuleAddressSanitizer::InstrumentGlobals(IRBuilder<> &IRB, Module &M,
bool *CtorComdat) {
+ *CtorComdat = false;
+
// Build set of globals that are aliased by some GA, where
// getExcludedAliasedGlobal(GA) returns the relevant GlobalVariable.
SmallPtrSet<const GlobalVariable *, 16> AliasedGlobalExclusions;
@@ -2362,6 +2364,11 @@
}
size_t n = GlobalsToChange.size();
+ if (n == 0) {
+ *CtorComdat = true;
+ return false;
+ }
+
auto &DL = M.getDataLayout();
// A global is described by a structure
@@ -2384,11 +2391,8 @@
// We shouldn't merge same module names, as this string serves as unique
// module ID in runtime.
- GlobalVariable *ModuleName =
- n != 0
- ? createPrivateGlobalForString(M, M.getModuleIdentifier(),
- /*AllowMerging*/ false, kAsanGenPrefix)
- : nullptr;
+ GlobalVariable *ModuleName = createPrivateGlobalForString(
+ M, M.getModuleIdentifier(), /*AllowMerging*/ false, kAsanGenPrefix);
for (size_t i = 0; i < n; i++) {
GlobalVariable *G = GlobalsToChange[i];
@@ -2513,27 +2517,19 @@
}
appendToCompilerUsed(M, ArrayRef<GlobalValue *>(GlobalsToAddToUsedList));
- if (UseGlobalsGC && TargetTriple.isOSBinFormatELF()) {
- // Use COMDAT and register globals even if n == 0 to ensure that (a) the
- // linkage unit will only have one module constructor, and (b) the register
- // function will be called. The module destructor is not created when n ==
- // 0.
+ std::string ELFUniqueModuleId =
+ (UseGlobalsGC && TargetTriple.isOSBinFormatELF()) ? getUniqueModuleId(&M)
+ : "";
+
+ if (!ELFUniqueModuleId.empty()) {
+ InstrumentGlobalsELF(IRB, M, NewGlobals, Initializers, ELFUniqueModuleId);
*CtorComdat = true;
- InstrumentGlobalsELF(IRB, M, NewGlobals, Initializers,
- getUniqueModuleId(&M));
- } else if (n == 0) {
- // When UseGlobalsGC is false, COMDAT can still be used if n == 0, because
- // all compile units will have identical module constructor/destructor.
- *CtorComdat = TargetTriple.isOSBinFormatELF();
+ } else if (UseGlobalsGC && TargetTriple.isOSBinFormatCOFF()) {
+ InstrumentGlobalsCOFF(IRB, M, NewGlobals, Initializers);
+ } else if (UseGlobalsGC && ShouldUseMachOGlobalsSection()) {
+ InstrumentGlobalsMachO(IRB, M, NewGlobals, Initializers);
} else {
- *CtorComdat = false;
- if (UseGlobalsGC && TargetTriple.isOSBinFormatCOFF()) {
- InstrumentGlobalsCOFF(IRB, M, NewGlobals, Initializers);
- } else if (UseGlobalsGC && ShouldUseMachOGlobalsSection()) {
- InstrumentGlobalsMachO(IRB, M, NewGlobals, Initializers);
- } else {
- InstrumentGlobalsWithMetadataArray(IRB, M, NewGlobals, Initializers);
- }
+ InstrumentGlobalsWithMetadataArray(IRB, M, NewGlobals, Initializers);
}
// Create calls for poisoning before initializers run and unpoisoning after.
@@ -2541,6 +2537,7 @@
createInitializerPoisonCalls(M, ModuleName);
LLVM_DEBUG(dbgs() << M);
+ return true;
}
uint64_t
diff --git a/test/Instrumentation/AddressSanitizer/basic.ll b/test/Instrumentation/AddressSanitizer/basic.ll
index f9c5b14..068d6d1 100644
--- a/test/Instrumentation/AddressSanitizer/basic.ll
+++ b/test/Instrumentation/AddressSanitizer/basic.ll
@@ -210,10 +210,8 @@
;; ctor/dtor have the nounwind attribute. See uwtable.ll, they additionally have
;; the uwtable attribute with the module flag "uwtable".
-; CHECK: define internal void @asan.module_ctor() #[[#ATTR:]] comdat {
+; CHECK: define internal void @asan.module_ctor() #[[#ATTR:]] {{(comdat )?}}{
; CHECK: call void @__asan_init()
-;; __asan_register_elf_globals is called even if this module does not contain global variables.
-; CHECK: call void @__asan_register_elf_globals(i64 ptrtoint (ptr @___asan_globals_registered to i64), i64 ptrtoint (ptr @__start_asan_globals to i64), i64 ptrtoint (ptr @__stop_asan_globals to i64))
; CHECK: attributes #[[#ATTR]] = { nounwind }
diff --git a/test/Instrumentation/AddressSanitizer/global_metadata_array.ll b/test/Instrumentation/AddressSanitizer/global_metadata_array.ll
index 1617bf9..0e4d1f1 100644
--- a/test/Instrumentation/AddressSanitizer/global_metadata_array.ll
+++ b/test/Instrumentation/AddressSanitizer/global_metadata_array.ll
@@ -1,12 +1,8 @@
-; RUN: rm -rf %t && split-file %s %t && cd %t
-; RUN: opt < a.ll -passes=asan -asan-globals-live-support=0 -mtriple=x86_64-unknown-linux-gnu -S | FileCheck --check-prefix=CHECK %s
-; RUN: opt < a.ll -passes=asan -asan-globals-live-support=0 -mtriple=x86_64-apple-macosx10.11.0 -S | FileCheck --check-prefix=CHECK %s
-; RUN: opt < a.ll -passes=asan -asan-globals-live-support=0 -mtriple=x86_64-pc-windows-msvc19.0.24215 -S | FileCheck --check-prefix=CHECK %s
-; RUN: opt < a.ll -passes=asan -asan-globals-live-support=0 -asan-mapping-scale=5 -mtriple=x86_64-unknown-linux-gnu -S | FileCheck --check-prefixes=CHECK,CHECK-S5 %s
+; RUN: opt < %s -passes=asan -asan-globals-live-support=0 -mtriple=x86_64-unknown-linux-gnu -S | FileCheck --check-prefix=CHECK %s
+; RUN: opt < %s -passes=asan -asan-globals-live-support=0 -mtriple=x86_64-apple-macosx10.11.0 -S | FileCheck --check-prefix=CHECK %s
+; RUN: opt < %s -passes=asan -asan-globals-live-support=0 -mtriple=x86_64-pc-windows-msvc19.0.24215 -S | FileCheck --check-prefix=CHECK %s
+; RUN: opt < %s -passes=asan -asan-globals-live-support=0 -asan-mapping-scale=5 -mtriple=x86_64-unknown-linux-gnu -S | FileCheck --check-prefixes=CHECK,CHECK-S5 %s
-; RUN: opt < empty.ll -passes=asan -asan-globals-live-support=0 -mtriple=x86_64-unknown-linux-gnu -S | FileCheck --check-prefix=ELF-NOGC %s
-
-;--- a.ll
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
; Globals:
@@ -63,10 +59,3 @@
!7 = !{!"/tmp/asan-globals.cpp", i32 7, i32 5}
!8 = !{!"/tmp/asan-globals.cpp", i32 12, i32 14}
!9 = !{!"/tmp/asan-globals.cpp", i32 14, i32 25}
-
-;; In the presence of instrumented global variables, asan.module_ctor do not use comdat.
-; CHECK: define internal void @asan.module_ctor() #[[#ATTR:]] {
-
-; ELF-NOGC: define internal void @asan.module_ctor() #[[#ATTR:]] comdat {
-
-;--- empty.ll
