[llvm] [BOLT] Support runtime library hook via DT_INIT_ARRAY (PR #167467)
Vasily Leonenko via llvm-commits
llvm-commits at lists.llvm.org
Sun Nov 30 23:04:51 PST 2025
https://github.com/vleonen updated https://github.com/llvm/llvm-project/pull/167467
>From a8552572fb15a0337ffba327d310c0c84fc8d2a1 Mon Sep 17 00:00:00 2001
From: Vasily Leonenko <vasily.leonenko at huawei.com>
Date: Sun, 9 Nov 2025 14:55:06 -0500
Subject: [PATCH 1/6] [BOLT] Support runtime library hook via DT_INIT_ARRAY
This commit follows implementation of instrumentation hook via
DT_FINI_ARRAY (#67348) and extends it for BOLT runtime libraries
(including instrumentation library) initialization hooking.
Initialization has has differences compared to finalization:
- Executables always use ELF entry point address. Update code
checks it and updates init_array entry if ELF is shared library
(have no interp entry) and have no DT_INIT entry. Also this
commit introduces "runtime-lib-init-hook" option to select
primary initialization hook (entry_point, init, init_array)
with fall back to next available hook in input binary.
e.g. in case of libc we can explicitly set it to init_array.
- Shared library init_array entries relocations usually has
R_AARCH64_ABS64 type on AArch64 binaries. We check relocation
type and adjust methods for reading init_array relocations in
discovery and update methods.
---
bolt/docs/CommandLineArgumentReference.md | 9 ++
bolt/include/bolt/Core/BinaryContext.h | 9 ++
bolt/include/bolt/Rewrite/RewriteInstance.h | 9 ++
bolt/lib/Rewrite/RewriteInstance.cpp | 166 +++++++++++++++++++-
4 files changed, 185 insertions(+), 8 deletions(-)
diff --git a/bolt/docs/CommandLineArgumentReference.md b/bolt/docs/CommandLineArgumentReference.md
index 7c6e01d669b74..0dbf6f59d5e88 100644
--- a/bolt/docs/CommandLineArgumentReference.md
+++ b/bolt/docs/CommandLineArgumentReference.md
@@ -811,6 +811,15 @@
Specify file name of the runtime instrumentation library
+- `--runtime-lib-init-hook=<value>`
+
+ Primary target for hooking runtime library initialization, used in
+ fallback order of availability in input binary (entry_point -> init
+ -> init_array) (default: entry_point)
+ - `entry_point`: use ELF Header Entry Point
+ - `init`: use ELF DT_INIT entry
+ - `init_array`: use ELF .init_array entry
+
- `--sctc-mode=<value>`
Mode for simplify conditional tail calls
diff --git a/bolt/include/bolt/Core/BinaryContext.h b/bolt/include/bolt/Core/BinaryContext.h
index 2af1d330b7545..8a90febcea3cc 100644
--- a/bolt/include/bolt/Core/BinaryContext.h
+++ b/bolt/include/bolt/Core/BinaryContext.h
@@ -807,6 +807,15 @@ class BinaryContext {
/// the execution of the binary is completed.
std::optional<uint64_t> FiniFunctionAddress;
+ /// DT_INIT.
+ std::optional<uint64_t> InitAddress;
+
+ /// DT_INIT_ARRAY. Only used when DT_INIT is not set.
+ std::optional<uint64_t> InitArrayAddress;
+
+ /// DT_INIT_ARRAYSZ. Only used when DT_INIT is not set.
+ std::optional<uint64_t> InitArraySize;
+
/// DT_FINI.
std::optional<uint64_t> FiniAddress;
diff --git a/bolt/include/bolt/Rewrite/RewriteInstance.h b/bolt/include/bolt/Rewrite/RewriteInstance.h
index 35abf6b4d4ddd..6b2a0143bbc42 100644
--- a/bolt/include/bolt/Rewrite/RewriteInstance.h
+++ b/bolt/include/bolt/Rewrite/RewriteInstance.h
@@ -93,11 +93,20 @@ class RewriteInstance {
/// section allocations if found.
void discoverBOLTReserved();
+ /// Check whether we should use DT_INIT or DT_INIT_ARRAY for instrumentation.
+ /// DT_INIT is preferred; DT_INIT_ARRAY is only used when no DT_INIT entry was
+ /// found.
+ Error discoverRtInitAddress();
+
/// Check whether we should use DT_FINI or DT_FINI_ARRAY for instrumentation.
/// DT_FINI is preferred; DT_FINI_ARRAY is only used when no DT_FINI entry was
/// found.
Error discoverRtFiniAddress();
+ /// If DT_INIT_ARRAY is used for instrumentation, update the relocation of its
+ /// first entry to point to the instrumentation library's init address.
+ Error updateRtInitReloc();
+
/// If DT_FINI_ARRAY is used for instrumentation, update the relocation of its
/// first entry to point to the instrumentation library's fini address.
void updateRtFiniReloc();
diff --git a/bolt/lib/Rewrite/RewriteInstance.cpp b/bolt/lib/Rewrite/RewriteInstance.cpp
index 8a5bbe28e5f66..8a7800cadbb7e 100644
--- a/bolt/lib/Rewrite/RewriteInstance.cpp
+++ b/bolt/lib/Rewrite/RewriteInstance.cpp
@@ -294,6 +294,28 @@ cl::bits<GadgetScannerKind> GadgetScannersToRun(
clEnumValN(GS_ALL, "all", "All implemented scanners")),
cl::ZeroOrMore, cl::CommaSeparated, cl::cat(BinaryAnalysisCategory));
+// Primary targets for hooking runtime library initialization hooking
+// with fallback to next item in case if current item is not available
+// in the input binary.
+enum RuntimeLibInitHookTarget : char {
+ RLIH_ENTRY_POINT = 0, /// Use ELF Header Entry Point
+ RLIH_INIT = 1, /// Use ELF DT_INIT entry
+ RLIH_INIT_ARRAY = 2, /// Use ELF .init_array entry
+};
+
+cl::opt<RuntimeLibInitHookTarget> RuntimeLibInitHook(
+ "runtime-lib-init-hook",
+ cl::desc("Primary target for hooking runtime library initialization, used "
+ "in fallback order of availabiliy in input binary (entry_point -> "
+ "init -> init_array) (default: entry_point)"),
+ cl::Hidden, cl::init(RLIH_ENTRY_POINT),
+ cl::values(clEnumValN(RLIH_ENTRY_POINT, "entry_point",
+ "use ELF Header Entry Point"),
+ clEnumValN(RLIH_INIT, "init", "use ELF DT_INIT entry"),
+ clEnumValN(RLIH_INIT_ARRAY, "init_array",
+ "use ELF .init_array entry")),
+ cl::ZeroOrMore, cl::cat(BoltOptCategory));
+
} // namespace opts
// FIXME: implement a better way to mark sections for replacement.
@@ -741,9 +763,12 @@ Error RewriteInstance::run() {
adjustCommandLineOptions();
discoverFileObjects();
- if (opts::Instrument && !BC->IsStaticExecutable)
+ if (opts::Instrument && !BC->IsStaticExecutable) {
+ if (Error E = discoverRtInitAddress())
+ return E;
if (Error E = discoverRtFiniAddress())
return E;
+ }
preprocessProfileData();
@@ -785,8 +810,11 @@ Error RewriteInstance::run() {
updateMetadata();
- if (opts::Instrument && !BC->IsStaticExecutable)
+ if (opts::Instrument && !BC->IsStaticExecutable) {
+ if (Error E = updateRtInitReloc())
+ return E;
updateRtFiniReloc();
+ }
if (opts::OutputFilename == "/dev/null") {
BC->outs() << "BOLT-INFO: skipping writing final binary to disk\n";
@@ -1411,6 +1439,60 @@ void RewriteInstance::discoverBOLTReserved() {
NextAvailableAddress = BC->BOLTReserved.start();
}
+Error RewriteInstance::discoverRtInitAddress() {
+ if (BC->HasInterpHeader && opts::RuntimeLibInitHook == opts::RLIH_ENTRY_POINT)
+ return Error::success();
+
+ // Use DT_INIT if it's available.
+ if (BC->InitAddress && opts::RuntimeLibInitHook <= opts::RLIH_INIT) {
+ BC->StartFunctionAddress = BC->InitAddress;
+ return Error::success();
+ }
+
+ if (!BC->InitArrayAddress || !BC->InitArraySize) {
+ return createStringError(std::errc::not_supported,
+ "Instrumentation of shared library needs either "
+ "DT_INIT or DT_INIT_ARRAY");
+ }
+
+ if (*BC->InitArraySize < BC->AsmInfo->getCodePointerSize()) {
+ return createStringError(std::errc::not_supported,
+ "Need at least 1 DT_INIT_ARRAY slot");
+ }
+
+ ErrorOr<BinarySection &> InitArraySection =
+ BC->getSectionForAddress(*BC->InitArrayAddress);
+ if (auto EC = InitArraySection.getError())
+ return errorCodeToError(EC);
+
+ if (const Relocation *Reloc = InitArraySection->getDynamicRelocationAt(0)) {
+ if (Reloc->isRelative()) {
+ BC->StartFunctionAddress = Reloc->Addend;
+ } else {
+ MCSymbol *Sym = Reloc->Symbol;
+ if (!Sym)
+ return createStringError(
+ std::errc::not_supported,
+ "Failed to locate symbol for 0 entry of .init_array");
+ const BinaryFunction *BF = BC->getFunctionForSymbol(Sym);
+ if (!BF)
+ return createStringError(
+ std::errc::not_supported,
+ "Failed to locate binary function for 0 entry of .init_array");
+ BC->StartFunctionAddress = BF->getAddress() + Reloc->Addend;
+ }
+ return Error::success();
+ }
+
+ if (const Relocation *Reloc = InitArraySection->getRelocationAt(0)) {
+ BC->StartFunctionAddress = Reloc->Value;
+ return Error::success();
+ }
+
+ return createStringError(std::errc::not_supported,
+ "No relocation for first DT_INIT_ARRAY slot");
+}
+
Error RewriteInstance::discoverRtFiniAddress() {
// Use DT_FINI if it's available.
if (BC->FiniAddress) {
@@ -1448,6 +1530,68 @@ Error RewriteInstance::discoverRtFiniAddress() {
"No relocation for first DT_FINI_ARRAY slot");
}
+Error RewriteInstance::updateRtInitReloc() {
+ if (BC->HasInterpHeader && opts::RuntimeLibInitHook == opts::RLIH_ENTRY_POINT)
+ return Error::success();
+
+ // Updating DT_INIT is handled by patchELFDynamic.
+ if (BC->InitAddress && opts::RuntimeLibInitHook <= opts::RLIH_INIT)
+ return Error::success();
+
+ const RuntimeLibrary *RT = BC->getRuntimeLibrary();
+ if (!RT || !RT->getRuntimeStartAddress())
+ return Error::success();
+
+ if (!BC->InitArrayAddress)
+ return Error::success();
+
+ if (!BC->InitArrayAddress || !BC->InitArraySize)
+ return createStringError(std::errc::not_supported,
+ "inconsistent .init_array state");
+
+ ErrorOr<BinarySection &> InitArraySection =
+ BC->getSectionForAddress(*BC->InitArrayAddress);
+ if (!InitArraySection)
+ return createStringError(std::errc::not_supported, ".init_array removed");
+
+ if (std::optional<Relocation> Reloc =
+ InitArraySection->takeDynamicRelocationAt(0)) {
+ if (Reloc->isRelative()) {
+ if (Reloc->Addend != BC->StartFunctionAddress)
+ return createStringError(std::errc::not_supported,
+ "inconsistent .init_array dynamic relocation");
+ Reloc->Addend = RT->getRuntimeStartAddress();
+ InitArraySection->addDynamicRelocation(*Reloc);
+ } else {
+ MCSymbol *Sym = Reloc->Symbol;
+ if (!Sym)
+ return createStringError(
+ std::errc::not_supported,
+ "Failed to locate symbol for 0 entry of .init_array");
+ const BinaryFunction *BF = BC->getFunctionForSymbol(Sym);
+ if (!BF)
+ return createStringError(
+ std::errc::not_supported,
+ "Failed to locate binary function for 0 entry of .init_array");
+ if (BF->getAddress() + Reloc->Addend != BC->StartFunctionAddress)
+ return createStringError(std::errc::not_supported,
+ "inconsistent .init_array dynamic relocation");
+ InitArraySection->addDynamicRelocation(Relocation{
+ /*Offset*/ 0, /*Symbol*/ nullptr, /*Type*/ Relocation::getAbs64(),
+ /*Addend*/ RT->getRuntimeStartAddress(), /*Value*/ 0});
+ }
+ }
+ // Update the static relocation by adding a pending relocation which will get
+ // patched when flushPendingRelocations is called in rewriteFile. Note that
+ // flushPendingRelocations will calculate the value to patch as
+ // "Symbol + Addend". Since we don't have a symbol, just set the addend to the
+ // desired value.
+ InitArraySection->addPendingRelocation(Relocation{
+ /*Offset*/ 0, /*Symbol*/ nullptr, /*Type*/ Relocation::getAbs64(),
+ /*Addend*/ RT->getRuntimeStartAddress(), /*Value*/ 0});
+ return Error::success();
+}
+
void RewriteInstance::updateRtFiniReloc() {
// Updating DT_FINI is handled by patchELFDynamic.
if (BC->FiniAddress)
@@ -4849,7 +4993,8 @@ void RewriteInstance::patchELFSectionHeaderTable(ELFObjectFile<ELFT> *File) {
ELFEhdrTy NewEhdr = Obj.getHeader();
if (BC->HasRelocations) {
- if (RuntimeLibrary *RtLibrary = BC->getRuntimeLibrary())
+ RuntimeLibrary *RtLibrary = BC->getRuntimeLibrary();
+ if (RtLibrary && opts::RuntimeLibInitHook == opts::RLIH_ENTRY_POINT)
NewEhdr.e_entry = RtLibrary->getRuntimeStartAddress();
else
NewEhdr.e_entry = getNewFunctionAddress(NewEhdr.e_entry);
@@ -5695,7 +5840,9 @@ void RewriteInstance::patchELFDynamic(ELFObjectFile<ELFT> *File) {
if (uint64_t Addr = RtLibrary->getRuntimeFiniAddress())
NewDE.d_un.d_ptr = Addr;
}
- if (RtLibrary && Dyn.getTag() == ELF::DT_INIT && !BC->HasInterpHeader) {
+ if (RtLibrary && Dyn.getTag() == ELF::DT_INIT &&
+ (!BC->HasInterpHeader ||
+ opts::RuntimeLibInitHook == opts::RLIH_INIT)) {
if (auto Addr = RtLibrary->getRuntimeStartAddress()) {
LLVM_DEBUG(dbgs() << "BOLT-DEBUG: Set DT_INIT to 0x"
<< Twine::utohexstr(Addr) << '\n');
@@ -5767,10 +5914,13 @@ Error RewriteInstance::readELFDynamic(ELFObjectFile<ELFT> *File) {
for (const Elf_Dyn &Dyn : DynamicEntries) {
switch (Dyn.d_tag) {
case ELF::DT_INIT:
- if (!BC->HasInterpHeader) {
- LLVM_DEBUG(dbgs() << "BOLT-DEBUG: Set start function address\n");
- BC->StartFunctionAddress = Dyn.getPtr();
- }
+ BC->InitAddress = Dyn.getPtr();
+ break;
+ case ELF::DT_INIT_ARRAY:
+ BC->InitArrayAddress = Dyn.getPtr();
+ break;
+ case ELF::DT_INIT_ARRAYSZ:
+ BC->InitArraySize = Dyn.getPtr();
break;
case ELF::DT_FINI:
BC->FiniAddress = Dyn.getPtr();
>From 16041ce5718b5ba81acf020fcf0ba65d1ecc6c1a Mon Sep 17 00:00:00 2001
From: Vasily Leonenko <vasily.leonenko at huawei.com>
Date: Thu, 6 Nov 2025 15:36:03 -0500
Subject: [PATCH 2/6] [BOLT][test] Add hook-init tests for checking
instrumentation initialization
---
bolt/test/AArch64/hook-init.s | 206 ++++++++++++++++++++++++++++++++++
bolt/test/X86/hook-init.s | 206 ++++++++++++++++++++++++++++++++++
2 files changed, 412 insertions(+)
create mode 100644 bolt/test/AArch64/hook-init.s
create mode 100644 bolt/test/X86/hook-init.s
diff --git a/bolt/test/AArch64/hook-init.s b/bolt/test/AArch64/hook-init.s
new file mode 100644
index 0000000000000..e5b11ecae57cc
--- /dev/null
+++ b/bolt/test/AArch64/hook-init.s
@@ -0,0 +1,206 @@
+## Test the different ways of hooking the init function for instrumentation (via
+## entry point, DT_INIT and via DT_INIT_ARRAY). We test the latter for both PIE
+## and non-PIE binaries because of the different ways of handling relocations
+## (static or dynamic), executable and shared library.
+## All tests perform the following steps:
+## - Compile and link for the case to be tested
+## - Some sanity-checks on the dynamic section and relocations in the binary to
+## verify it has the shape we want for testing:
+## - INTERP in Program Headers
+## - DT_INIT or DT_INIT_ARRAY in dynamic section
+## - No relative relocations for non-PIE
+## - Instrument (with extra --runtime-lib-init-hook=init/init_array options
+## in some cases)
+## - Verify generated binary
+# REQUIRES: system-linux,bolt-runtime,target=aarch64{{.*}}
+
+# RUN: %clang %cflags -pie %s -Wl,-q -o %t.exe
+# RUN: llvm-readelf -d %t.exe | FileCheck --check-prefix=DYN-INIT %s
+# RUN: llvm-readelf -l %t.exe | FileCheck --check-prefix=PH-INTERP %s
+# RUN: llvm-readelf -r %t.exe | FileCheck --check-prefix=RELOC-PIE %s
+# RUN: llvm-bolt %t.exe -o %t --instrument
+# RUN: llvm-readelf -hdrs %t | FileCheck --check-prefix=CHECK-INIT-EP %s
+# RUN: llvm-bolt %t.exe -o %t-no-ep --instrument --runtime-lib-init-hook=init
+# RUN: llvm-readelf -hdrs %t-no-ep | FileCheck --check-prefix=CHECK-INIT-NO-EP %s
+# RUN: llvm-bolt %t.exe -o %t-no-ep --instrument --runtime-lib-init-hook=init_array
+# RUN: llvm-readelf -hdrs %t-no-ep | FileCheck --check-prefix=CHECK-INIT-ARRAY-NO-EP %s
+
+# RUN: %clang -shared %cflags -pie %s -Wl,-q -o %t-shared.exe
+# RUN: llvm-readelf -d %t-shared.exe | FileCheck --check-prefix=DYN-INIT %s
+# RUN: llvm-readelf -l %t-shared.exe | FileCheck --check-prefix=PH-INTERP-SHARED %s
+# RUN: llvm-readelf -r %t-shared.exe | FileCheck --check-prefix=RELOC-SHARED-PIE %s
+# RUN: llvm-bolt %t-shared.exe -o %t-shared --instrument
+# RUN: llvm-readelf -hdrs %t-shared | FileCheck --check-prefix=CHECK-SHARED-INIT %s
+
+# RUN: %clang %cflags -pie %s -Wl,-q,-init=0 -o %t-no-init.exe
+# RUN: llvm-readelf -d %t-no-init.exe | FileCheck --check-prefix=DYN-NO-INIT %s
+# RUN: llvm-readelf -l %t-no-init.exe | FileCheck --check-prefix=PH-INTERP %s
+# RUN: llvm-readelf -r %t-no-init.exe | FileCheck --check-prefix=RELOC-PIE %s
+# RUN: llvm-bolt %t-no-init.exe -o %t-no-init --instrument
+# RUN: llvm-readelf -hdrs %t-no-init | FileCheck --check-prefix=CHECK-NO-INIT-EP %s
+# RUN: llvm-bolt %t-no-init.exe -o %t-no-init-no-ep --instrument --runtime-lib-init-hook=init
+# RUN: llvm-readelf -hdrs %t-no-init-no-ep | FileCheck --check-prefix=CHECK-NO-INIT-NO-EP %s
+
+# RUN: %clang -shared %cflags -pie %s -Wl,-q,-init=0 -o %t-shared-no-init.exe
+# RUN: llvm-readelf -d %t-shared-no-init.exe | FileCheck --check-prefix=DYN-NO-INIT %s
+# RUN: llvm-readelf -l %t-shared-no-init.exe | FileCheck --check-prefix=PH-INTERP-SHARED %s
+# RUN: llvm-readelf -r %t-shared-no-init.exe | FileCheck --check-prefix=RELOC-SHARED-PIE %s
+# RUN: llvm-bolt %t-shared-no-init.exe -o %t-shared-no-init --instrument
+# RUN: llvm-readelf -drs %t-shared-no-init | FileCheck --check-prefix=CHECK-SHARED-NO-INIT %s
+
+## Create a dummy shared library to link against to force creation of the dynamic section.
+# RUN: %clang %cflags %p/../Inputs/stub.c -fPIC -shared -o %t-stub.so
+# RUN: %clang %cflags %s -no-pie -Wl,-q,-init=0 %t-stub.so -o %t-no-pie-no-init.exe
+# RUN: llvm-readelf -r %t-no-pie-no-init.exe | FileCheck --check-prefix=RELOC-NO-PIE %s
+# RUN: llvm-bolt %t-no-pie-no-init.exe -o %t-no-pie-no-init --instrument
+# RUN: llvm-readelf -hds %t-no-pie-no-init | FileCheck --check-prefix=CHECK-NO-PIE-NO-INIT-EP %s
+
+## With init: dynamic section should contain DT_INIT
+# DYN-INIT: (INIT)
+
+## Without init: dynamic section should only contain DT_INIT_ARRAY
+# DYN-NO-INIT-NOT: (INIT)
+# DYN-NO-INIT: (INIT_ARRAY)
+# DYN-NO-INIT: (INIT_ARRAYSZ)
+
+## With interp program header (executable)
+# PH-INTERP: Program Headers:
+# PH-INTERP: INTERP
+
+## Without interp program header (shared library)
+# PH-INTERP-SHARED: Program Headers:
+# PH-INTERP-SHARED-NOT: INTERP
+
+## With PIE: binary should have relative relocations
+# RELOC-PIE: R_AARCH64_RELATIVE
+
+## With PIE: binary should have relative relocations
+# RELOC-SHARED-PIE: R_AARCH64_ABS64
+
+## Without PIE: binary should not have relative relocations
+# RELOC-NO-PIE-NOT: R_AARCH64_RELATIVE
+
+## Check that entry point address is set to __bolt_runtime_start for PIE executable with DT_INIT
+# CHECK-INIT-EP: ELF Header:
+# CHECK-INIT-EP: Entry point address: 0x[[#%x,EP_ADDR:]]
+## Check that the dynamic relocation at .init and .init_array were not patched
+# CHECK-INIT-EP: Dynamic section at offset {{.*}} contains {{.*}} entries:
+# CHECK-INIT-EP-NOT: (INIT) 0x[[#%x, EP_ADDR]]
+# CHECK-INIT-EP-NOT: (INIT_ARRAY) 0x[[#%x, EP_ADDR]]
+## Check that the new entry point address points to __bolt_runtime_start
+# CHECK-INIT-EP: Symbol table '.symtab' contains {{.*}} entries:
+# CHECK-INIT-EP: {{0+}}[[#%x, EP_ADDR]] {{.*}} __bolt_runtime_start
+
+## Check that DT_INIT address is set to __bolt_runtime_start for PIE executable with DT_INIT
+# CHECK-INIT-NO-EP: ELF Header:
+# CHECK-INIT-NO-EP: Entry point address: 0x[[#%x,EP_ADDR:]]
+## Read Dynamic section DT_INIT and DT_INIT_ARRAY entries
+# CHECK-INIT-NO-EP: Dynamic section at offset {{.*}} contains {{.*}} entries:
+# CHECK-INIT-NO-EP-DAG: (INIT) 0x[[#%x,INIT:]]
+# CHECK-INIT-NO-EP-DAG: (INIT_ARRAY) 0x[[#%x,INIT_ARRAY:]]
+## Check if ELF entry point address points to _start symbol and new DT_INIT entry points to __bolt_runtime_start
+# CHECK-INIT-NO-EP: Symbol table '.symtab' contains {{.*}} entries:
+# CHECK-INIT-NO-EP-DAG: {{0+}}[[#%x, EP_ADDR]] {{.*}} _start
+# CHECK-INIT-NO-EP-DAG: {{0+}}[[#%x, INIT]] {{.*}} __bolt_runtime_start
+
+## Check that 1st entry of DT_INIT_ARRAY is set to __bolt_runtime_start and DT_INIT was not changed
+# CHECK-INIT-ARRAY-NO-EP: ELF Header:
+# CHECK-INIT-ARRAY-NO-EP: Entry point address: 0x[[#%x,EP_ADDR:]]
+## Read Dynamic section DT_INIT and DT_INIT_ARRAY entries
+# CHECK-INIT-ARRAY-NO-EP: Dynamic section at offset {{.*}} contains {{.*}} entries:
+# CHECK-INIT-ARRAY-NO-EP-DAG: (INIT) 0x[[#%x,INIT:]]
+# CHECK-INIT-ARRAY-NO-EP-DAG: (INIT_ARRAY) 0x[[#%x,INIT_ARRAY:]]
+## Read the dynamic relocation from 1st entry of .init_array
+# CHECK-INIT-ARRAY-NO-EP: Relocation section '.rela.dyn' at offset {{.*}} contains {{.*}} entries
+# CHECK-INIT-ARRAY-NO-EP: {{0+}}[[#%x,INIT_ARRAY]] {{.*}} R_AARCH64_RELATIVE [[#%x,INIT_ADDR:]]
+# CHECK-INIT-ARRAY-NO-EP-NOT: {{0+}}[[#%x,INIT_ARRAY]] {{.*}} R_AARCH64_RELATIVE [[#%x,INIT]]
+## Check that 1st entry of .init_array points to __bolt_runtime_start
+# CHECK-INIT-ARRAY-NO-EP: Symbol table '.symtab' contains {{.*}} entries:
+# CHECK-INIT-ARRAY-NO-EP-DAG: {{0+}}[[#%x, EP_ADDR]] {{.*}} _start
+# CHECK-INIT-ARRAY-NO-EP-DAG: {{[0-9]]*}}: {{0+}}[[#%x, INIT_ADDR]] {{.*}} __bolt_runtime_start
+
+## Check that entry point address is set to __bolt_runtime_start for PIE executable without DT_INIT
+# CHECK-NO-INIT-EP: ELF Header:
+# CHECK-NO-INIT-EP: Entry point address: 0x[[#%x,EP_ADDR:]]
+## Check that the dynamic relocation at .init and .init_array were not patched
+# CHECK-NO-INIT-EP: Dynamic section at offset {{.*}} contains {{.*}} entries:
+# CHECK-NO-INIT-EP-NOT: (INIT) 0x[[#%x, EP_ADDR]]
+# CHECK-NO-INIT-EP-NOT: (INIT_ARRAY) 0x[[#%x, EP_ADDR]]
+## Check that the new entry point address points to __bolt_runtime_start
+# CHECK-NO-INIT-EP: Symbol table '.symtab' contains {{.*}} entries:
+# CHECK-NO-INIT-EP: {{0+}}[[#%x, EP_ADDR]] {{.*}} __bolt_runtime_start
+
+## Check that DT_INIT is set to __bolt_runtime_start for shared library with DT_INIT
+# CHECK-SHARED-INIT: Dynamic section at offset {{.*}} contains {{.*}} entries:
+# CHECK-SHARED-INIT-DAG: (INIT) 0x[[#%x, INIT:]]
+# CHECK-SHARED-INIT-DAG: (INIT_ARRAY) 0x[[#%x, INIT_ARRAY:]]
+## Check that the dynamic relocation at .init_array was not patched
+# CHECK-SHARED-INIT: Relocation section '.rela.dyn' at offset {{.*}} contains {{.*}} entries
+# CHECK-SHARED-INIT-NOT: {{0+}}[[#%x, INIT_ARRAY]] {{.*}} R_AARCH64_ABS64 {{0+}}[[#%x, INIT]]
+## Check that dynamic section DT_INIT points to __bolt_runtime_start
+# CHECK-SHARED-INIT: Symbol table '.symtab' contains {{.*}} entries:
+# CHECK-SHARED-INIT: {{0+}}[[#%x, INIT]] {{.*}} __bolt_runtime_start
+
+## Check that entry point address is set to __bolt_runtime_start for PIE executable without DT_INIT
+# CHECK-NO-INIT-NO-EP: ELF Header:
+# CHECK-NO-INIT-NO-EP: Entry point address: 0x[[#%x,EP_ADDR:]]
+# CHECK-NO-INIT-NO-EP: Dynamic section at offset {{.*}} contains {{.*}} entries:
+# CHECK-NO-INIT-NO-EP-NOT: (INIT)
+# CHECK-NO-INIT-NO-EP: (INIT_ARRAY) 0x[[#%x,INIT_ARRAY:]]
+## Read the dynamic relocation from 1st entry of .init_array
+# CHECK-NO-INIT-NO-EP: Relocation section '.rela.dyn' at offset {{.*}} contains {{.*}} entries
+# CHECK-NO-INIT-NO-EP: {{0+}}[[#%x,INIT_ARRAY]] {{.*}} R_AARCH64_RELATIVE [[#%x,INIT_ADDR:]]
+## Check that 1st entry of .init_array points to __bolt_runtime_start
+# CHECK-NO-INIT-NO-EP: Symbol table '.symtab' contains {{.*}} entries:
+# CHECK-NO-INIT-NO-EP-DAG: {{0+}}[[#%x, EP_ADDR]] {{.*}} _start
+# CHECK-NO-INIT-NO-EP-DAG: {{[0-9]]*}}: {{0+}}[[#%x, INIT_ADDR]] {{.*}} __bolt_runtime_start
+
+## Check that entry point address is set to __bolt_runtime_start for shared library without DT_INIT
+# CHECK-SHARED-NO-INIT: Dynamic section at offset {{.*}} contains {{.*}} entries:
+# CHECK-SHARED-NO-INIT-NOT: (INIT)
+# CHECK-SHARED-NO-INIT: (INIT_ARRAY) 0x[[#%x,INIT_ARRAY:]]
+## Read the dynamic relocation from 1st entry of .init_array
+# CHECK-SHARED-NO-INIT: Relocation section '.rela.dyn' at offset {{.*}} contains {{.*}} entries
+# CHECK-SHARED-NO-INIT: {{0+}}[[#%x, INIT_ARRAY]] {{.*}} R_AARCH64_ABS64 [[#%x,INIT_ADDR:]]
+## Check that 1st entry of .init_array points to __bolt_runtime_start
+# CHECK-SHARED-NO-INIT: Symbol table '.symtab' contains {{.*}} entries:
+# CHECK-SHARED-NO-INIT: {{[0-9]]*}}: {{0+}}[[#%x, INIT_ADDR]] {{.*}} __bolt_runtime_start
+
+## Check that entry point address is set to __bolt_runtime_start for non-PIE executable with DT_INIT
+# CHECK-NO-PIE-NO-INIT-EP: ELF Header:
+# CHECK-NO-PIE-NO-INIT-EP: Entry point address: 0x[[#%x,EP_ADDR:]]
+## Check that the dynamic relocation at .init and .init_array were not patched
+# CHECK-NO-PIE-NO-INIT-EP: Dynamic section at offset {{.*}} contains {{.*}} entries:
+# CHECK-NO-PIE-NO-INIT-EP-NOT: (INIT) 0x[[#%x, EP_ADDR]]
+# CHECK-NO-PIE-NO-INIT-EP-NOT: (INIT_ARRAY) 0x[[#%x, EP_ADDR]]
+## Check that the new entry point address points to __bolt_runtime_start
+# CHECK-NO-PIE-NO-INIT-EP: Symbol table '.symtab' contains {{.*}} entries:
+# CHECK-NO-PIE-NO-INIT-EP: {{0+}}[[#%x, EP_ADDR]] {{.*}} __bolt_runtime_start
+
+ .globl _start
+ .type _start, %function
+_start:
+ # Dummy relocation to force relocation mode.
+ .reloc 0, R_AARCH64_NONE
+ ret
+.size _start, .-_start
+
+ .globl _init
+ .type _init, %function
+_init:
+ ret
+ .size _init, .-_init
+
+ .globl _fini
+ .type _fini, %function
+_fini:
+ ret
+ .size _fini, .-_fini
+
+ .section .init_array,"aw"
+ .align 3
+ .dword _init
+
+ .section .fini_array,"aw"
+ .align 3
+ .dword _fini
diff --git a/bolt/test/X86/hook-init.s b/bolt/test/X86/hook-init.s
new file mode 100644
index 0000000000000..0c96bc7f95bcd
--- /dev/null
+++ b/bolt/test/X86/hook-init.s
@@ -0,0 +1,206 @@
+## Test the different ways of hooking the init function for instrumentation (via
+## entry point, DT_INIT and via DT_INIT_ARRAY). We test the latter for both PIE
+## and non-PIE binaries because of the different ways of handling relocations
+## (static or dynamic), executable and shared library.
+## All tests perform the following steps:
+## - Compile and link for the case to be tested
+## - Some sanity-checks on the dynamic section and relocations in the binary to
+## verify it has the shape we want for testing:
+## - INTERP in Program Headers
+## - DT_INIT or DT_INIT_ARRAY in dynamic section
+## - No relative relocations for non-PIE
+## - Instrument (with extra --runtime-lib-init-hook=init/init_array options
+## in some cases)
+## - Verify generated binary
+# REQUIRES: system-linux,bolt-runtime,target=x86_64-{{.*}}
+
+# RUN: %clang %cflags -pie %s -Wl,-q -o %t.exe
+# RUN: llvm-readelf -d %t.exe | FileCheck --check-prefix=DYN-INIT %s
+# RUN: llvm-readelf -l %t.exe | FileCheck --check-prefix=PH-INTERP %s
+# RUN: llvm-readelf -r %t.exe | FileCheck --check-prefix=RELOC-PIE %s
+# RUN: llvm-bolt %t.exe -o %t --instrument | FileCheck --check-prefix=CHECK-BOLT-RT-EP %s
+# RUN: llvm-readelf -hdrs %t | FileCheck --check-prefix=CHECK-INIT-EP %s
+# RUN: llvm-bolt %t.exe -o %t-no-ep --instrument --runtime-lib-init-hook=init
+# RUN: llvm-readelf -hdrs %t-no-ep | FileCheck --check-prefix=CHECK-INIT-NO-EP %s
+# RUN: llvm-bolt %t.exe -o %t-no-ep --instrument --runtime-lib-init-hook=init_array
+# RUN: llvm-readelf -hdrs %t-no-ep | FileCheck --check-prefix=CHECK-INIT-ARRAY-NO-EP %s
+
+# RUN: %clang -shared %cflags -pie %s -Wl,-q -o %t-shared.exe
+# RUN: llvm-readelf -d %t-shared.exe | FileCheck --check-prefix=DYN-INIT %s
+# RUN: llvm-readelf -l %t-shared.exe | FileCheck --check-prefix=PH-INTERP-SHARED %s
+# RUN: llvm-readelf -r %t-shared.exe | FileCheck --check-prefix=RELOC-SHARED-PIE %s
+# RUN: llvm-bolt %t-shared.exe -o %t-shared --instrument | FileCheck --check-prefix=CHECK-BOLT-RT-INIT %s
+# RUN: llvm-readelf -hdrs %t-shared | FileCheck --check-prefix=CHECK-SHARED-INIT %s
+
+# RUN: %clang %cflags -pie %s -Wl,-q,-init=0 -o %t-no-init.exe
+# RUN: llvm-readelf -d %t-no-init.exe | FileCheck --check-prefix=DYN-NO-INIT %s
+# RUN: llvm-readelf -l %t-no-init.exe | FileCheck --check-prefix=PH-INTERP %s
+# RUN: llvm-readelf -r %t-no-init.exe | FileCheck --check-prefix=RELOC-PIE %s
+# RUN: llvm-bolt %t-no-init.exe -o %t-no-init --instrument | FileCheck --check-prefix=CHECK-BOLT-RT-EP %s
+# RUN: llvm-readelf -hdrs %t-no-init | FileCheck --check-prefix=CHECK-NO-INIT-EP %s
+# RUN: llvm-bolt %t-no-init.exe -o %t-no-init-no-ep --instrument --runtime-lib-init-hook=init
+# RUN: llvm-readelf -hdrs %t-no-init-no-ep | FileCheck --check-prefix=CHECK-NO-INIT-NO-EP %s
+
+# RUN: %clang -shared %cflags -pie %s -Wl,-q,-init=0 -o %t-shared-no-init.exe
+# RUN: llvm-readelf -d %t-shared-no-init.exe | FileCheck --check-prefix=DYN-NO-INIT %s
+# RUN: llvm-readelf -l %t-shared-no-init.exe | FileCheck --check-prefix=PH-INTERP-SHARED %s
+# RUN: llvm-readelf -r %t-shared-no-init.exe | FileCheck --check-prefix=RELOC-SHARED-PIE %s
+# RUN: llvm-bolt %t-shared-no-init.exe -o %t-shared-no-init --instrument
+# RUN: llvm-readelf -drs %t-shared-no-init | FileCheck --check-prefix=CHECK-SHARED-NO-INIT %s
+
+## Create a dummy shared library to link against to force creation of the dynamic section.
+# RUN: %clang %cflags %p/../Inputs/stub.c -fPIC -shared -o %t-stub.so
+# RUN: %clang %cflags %s -no-pie -Wl,-q,-init=0 %t-stub.so -o %t-no-pie-no-init.exe
+# RUN: llvm-readelf -r %t-no-pie-no-init.exe | FileCheck --check-prefix=RELOC-NO-PIE %s
+# RUN: llvm-bolt %t-no-pie-no-init.exe -o %t-no-pie-no-init --instrument
+# RUN: llvm-readelf -hds %t-no-pie-no-init | FileCheck --check-prefix=CHECK-NO-PIE-NO-INIT-EP %s
+
+## With init: dynamic section should contain DT_INIT
+# DYN-INIT: (INIT)
+
+## Without init: dynamic section should only contain DT_INIT_ARRAY
+# DYN-NO-INIT-NOT: (INIT)
+# DYN-NO-INIT: (INIT_ARRAY)
+# DYN-NO-INIT: (INIT_ARRAYSZ)
+
+## With interp program header (executable)
+# PH-INTERP: Program Headers:
+# PH-INTERP: INTERP
+
+## Without interp program header (shared library)
+# PH-INTERP-SHARED: Program Headers:
+# PH-INTERP-SHARED-NOT: INTERP
+
+## With PIE: binary should have relative relocations
+# RELOC-PIE: R_X86_64_RELATIVE
+
+## With PIE: binary should have relative relocations
+# RELOC-SHARED-PIE: R_X86_64_64
+
+## Without PIE: binary should not have relative relocations
+# RELOC-NO-PIE-NOT: R_X86_64_RELATIVE
+
+## Check that entry point address is set to __bolt_runtime_start for PIE executable with DT_INIT
+# CHECK-INIT-EP: ELF Header:
+# CHECK-INIT-EP: Entry point address: 0x[[#%x,EP_ADDR:]]
+## Check that the dynamic relocation at .init and .init_array were not patched
+# CHECK-INIT-EP: Dynamic section at offset {{.*}} contains {{.*}} entries:
+# CHECK-INIT-EP-NOT: (INIT) 0x[[#%x, EP_ADDR]]
+# CHECK-INIT-EP-NOT: (INIT_ARRAY) 0x[[#%x, EP_ADDR]]
+## Check that the new entry point address points to __bolt_runtime_start
+# CHECK-INIT-EP: Symbol table '.symtab' contains {{.*}} entries:
+# CHECK-INIT-EP: {{0+}}[[#%x, EP_ADDR]] {{.*}} __bolt_runtime_start
+
+## Check that DT_INIT address is set to __bolt_runtime_start for PIE executable with DT_INIT
+# CHECK-INIT-NO-EP: ELF Header:
+# CHECK-INIT-NO-EP: Entry point address: 0x[[#%x,EP_ADDR:]]
+## Read Dynamic section DT_INIT and DT_INIT_ARRAY entries
+# CHECK-INIT-NO-EP: Dynamic section at offset {{.*}} contains {{.*}} entries:
+# CHECK-INIT-NO-EP-DAG: (INIT) 0x[[#%x,INIT:]]
+# CHECK-INIT-NO-EP-DAG: (INIT_ARRAY) 0x[[#%x,INIT_ARRAY:]]
+## Check if ELF entry point address points to _start symbol and new DT_INIT entry points to __bolt_runtime_start
+# CHECK-INIT-NO-EP: Symbol table '.symtab' contains {{.*}} entries:
+# CHECK-INIT-NO-EP-DAG: {{0+}}[[#%x, EP_ADDR]] {{.*}} _start
+# CHECK-INIT-NO-EP-DAG: {{0+}}[[#%x, INIT]] {{.*}} __bolt_runtime_start
+
+## Check that 1st entry of DT_INIT_ARRAY is set to __bolt_runtime_start and DT_INIT was not changed
+# CHECK-INIT-ARRAY-NO-EP: ELF Header:
+# CHECK-INIT-ARRAY-NO-EP: Entry point address: 0x[[#%x,EP_ADDR:]]
+## Read Dynamic section DT_INIT and DT_INIT_ARRAY entries
+# CHECK-INIT-ARRAY-NO-EP: Dynamic section at offset {{.*}} contains {{.*}} entries:
+# CHECK-INIT-ARRAY-NO-EP-DAG: (INIT) 0x[[#%x,INIT:]]
+# CHECK-INIT-ARRAY-NO-EP-DAG: (INIT_ARRAY) 0x[[#%x,INIT_ARRAY:]]
+## Read the dynamic relocation from 1st entry of .init_array
+# CHECK-INIT-ARRAY-NO-EP: Relocation section '.rela.dyn' at offset {{.*}} contains {{.*}} entries
+# CHECK-INIT-ARRAY-NO-EP: {{0+}}[[#%x,INIT_ARRAY]] {{.*}} R_X86_64_RELATIVE [[#%x,INIT_ADDR:]]
+# CHECK-INIT-ARRAY-NO-EP-NOT: {{0+}}[[#%x,INIT_ARRAY]] {{.*}} R_X86_64_RELATIVE [[#%x,INIT]]
+## Check that 1st entry of .init_array points to __bolt_runtime_start
+# CHECK-INIT-ARRAY-NO-EP: Symbol table '.symtab' contains {{.*}} entries:
+# CHECK-INIT-ARRAY-NO-EP-DAG: {{0+}}[[#%x, EP_ADDR]] {{.*}} _start
+# CHECK-INIT-ARRAY-NO-EP-DAG: {{[0-9]]*}}: {{0+}}[[#%x, INIT_ADDR]] {{.*}} __bolt_runtime_start
+
+## Check that entry point address is set to __bolt_runtime_start for PIE executable without DT_INIT
+# CHECK-NO-INIT-EP: ELF Header:
+# CHECK-NO-INIT-EP: Entry point address: 0x[[#%x,EP_ADDR:]]
+## Check that the dynamic relocation at .init and .init_array were not patched
+# CHECK-NO-INIT-EP: Dynamic section at offset {{.*}} contains {{.*}} entries:
+# CHECK-NO-INIT-EP-NOT: (INIT) 0x[[#%x, EP_ADDR]]
+# CHECK-NO-INIT-EP-NOT: (INIT_ARRAY) 0x[[#%x, EP_ADDR]]
+## Check that the new entry point address points to __bolt_runtime_start
+# CHECK-NO-INIT-EP: Symbol table '.symtab' contains {{.*}} entries:
+# CHECK-NO-INIT-EP: {{0+}}[[#%x, EP_ADDR]] {{.*}} __bolt_runtime_start
+
+## Check that DT_INIT is set to __bolt_runtime_start for shared library with DT_INIT
+# CHECK-SHARED-INIT: Dynamic section at offset {{.*}} contains {{.*}} entries:
+# CHECK-SHARED-INIT-DAG: (INIT) 0x[[#%x, INIT:]]
+# CHECK-SHARED-INIT-DAG: (INIT_ARRAY) 0x[[#%x, INIT_ARRAY:]]
+## Check that the dynamic relocation at .init_array was not patched
+# CHECK-SHARED-INIT: Relocation section '.rela.dyn' at offset {{.*}} contains {{.*}} entries
+# CHECK-SHARED-INIT-NOT: {{0+}}[[#%x, INIT_ARRAY]] {{.*}} R_X86_64_64 {{0+}}[[#%x, INIT]]
+## Check that dynamic section DT_INIT points to __bolt_runtime_start
+# CHECK-SHARED-INIT: Symbol table '.symtab' contains {{.*}} entries:
+# CHECK-SHARED-INIT: {{0+}}[[#%x, INIT]] {{.*}} __bolt_runtime_start
+
+## Check that entry point address is set to __bolt_runtime_start for PIE executable without DT_INIT
+# CHECK-NO-INIT-NO-EP: ELF Header:
+# CHECK-NO-INIT-NO-EP: Entry point address: 0x[[#%x,EP_ADDR:]]
+# CHECK-NO-INIT-NO-EP: Dynamic section at offset {{.*}} contains {{.*}} entries:
+# CHECK-NO-INIT-NO-EP-NOT: (INIT)
+# CHECK-NO-INIT-NO-EP: (INIT_ARRAY) 0x[[#%x,INIT_ARRAY:]]
+## Read the dynamic relocation from 1st entry of .init_array
+# CHECK-NO-INIT-NO-EP: Relocation section '.rela.dyn' at offset {{.*}} contains {{.*}} entries
+# CHECK-NO-INIT-NO-EP: {{0+}}[[#%x,INIT_ARRAY]] {{.*}} R_X86_64_RELATIVE [[#%x,INIT_ADDR:]]
+## Check that 1st entry of .init_array points to __bolt_runtime_start
+# CHECK-NO-INIT-NO-EP: Symbol table '.symtab' contains {{.*}} entries:
+# CHECK-NO-INIT-NO-EP-DAG: {{0+}}[[#%x, EP_ADDR]] {{.*}} _start
+# CHECK-NO-INIT-NO-EP-DAG: {{[0-9]]*}}: {{0+}}[[#%x, INIT_ADDR]] {{.*}} __bolt_runtime_start
+
+## Check that entry point address is set to __bolt_runtime_start for shared library without DT_INIT
+# CHECK-SHARED-NO-INIT: Dynamic section at offset {{.*}} contains {{.*}} entries:
+# CHECK-SHARED-NO-INIT-NOT: (INIT)
+# CHECK-SHARED-NO-INIT: (INIT_ARRAY) 0x[[#%x,INIT_ARRAY:]]
+## Read the dynamic relocation from 1st entry of .init_array
+# CHECK-SHARED-NO-INIT: Relocation section '.rela.dyn' at offset {{.*}} contains {{.*}} entries
+# CHECK-SHARED-NO-INIT: {{0+}}[[#%x, INIT_ARRAY]] {{.*}} R_X86_64_64 [[#%x,INIT_ADDR:]]
+## Check that 1st entry of .init_array points to __bolt_runtime_start
+# CHECK-SHARED-NO-INIT: Symbol table '.symtab' contains {{.*}} entries:
+# CHECK-SHARED-NO-INIT: {{[0-9]]*}}: {{0+}}[[#%x, INIT_ADDR]] {{.*}} __bolt_runtime_start
+
+## Check that entry point address is set to __bolt_runtime_start for non-PIE executable with DT_INIT
+# CHECK-NO-PIE-NO-INIT-EP: ELF Header:
+# CHECK-NO-PIE-NO-INIT-EP: Entry point address: 0x[[#%x,EP_ADDR:]]
+## Check that the dynamic relocation at .init and .init_array were not patched
+# CHECK-NO-PIE-NO-INIT-EP: Dynamic section at offset {{.*}} contains {{.*}} entries:
+# CHECK-NO-PIE-NO-INIT-EP-NOT: (INIT) 0x[[#%x, EP_ADDR]]
+# CHECK-NO-PIE-NO-INIT-EP-NOT: (INIT_ARRAY) 0x[[#%x, EP_ADDR]]
+## Check that the new entry point address points to __bolt_runtime_start
+# CHECK-NO-PIE-NO-INIT-EP: Symbol table '.symtab' contains {{.*}} entries:
+# CHECK-NO-PIE-NO-INIT-EP: {{0+}}[[#%x, EP_ADDR]] {{.*}} __bolt_runtime_start
+
+ .globl _start
+ .type _start, %function
+_start:
+ # Dummy relocation to force relocation mode.
+ .reloc 0, R_X86_64_NONE
+ retq
+.size _start, .-_start
+
+ .globl _init
+ .type _init, %function
+_init:
+ retq
+ .size _init, .-_init
+
+ .globl _fini
+ .type _fini, %function
+_fini:
+ retq
+ .size _fini, .-_fini
+
+ .section .init_array,"aw"
+ .align 8
+ .quad _init
+
+ .section .fini_array,"aw"
+ .align 8
+ .quad _fini
>From 5c511831a69a37f1ddfa4c36d8e77c7c3aed756c Mon Sep 17 00:00:00 2001
From: Vasily Leonenko <vasily.leonenko at huawei.com>
Date: Mon, 10 Nov 2025 00:43:29 +0300
Subject: [PATCH 3/6] [BOLT][test] Fix instrumentation tests for X86 (add .init
entries)
---
bolt/test/X86/internal-call-instrument-so.s | 9 ++++++++-
bolt/test/runtime/X86/instrument-wrong-target.s | 7 +++++++
2 files changed, 15 insertions(+), 1 deletion(-)
diff --git a/bolt/test/X86/internal-call-instrument-so.s b/bolt/test/X86/internal-call-instrument-so.s
index 99e5b29221409..fe23bc61afa32 100644
--- a/bolt/test/X86/internal-call-instrument-so.s
+++ b/bolt/test/X86/internal-call-instrument-so.s
@@ -5,7 +5,7 @@
# RUN: llvm-mc -filetype=obj -triple x86_64-unknown-unknown %s -o %t.o
# Delete our BB symbols so BOLT doesn't mark them as entry points
# RUN: llvm-strip --strip-unneeded %t.o
-# RUN: ld.lld %t.o -o %t.exe -q -shared -fini=_fini
+# RUN: ld.lld %t.o -o %t.exe -q -shared -fini=_fini -init=_init
# RUN: llvm-bolt --instrument %t.exe --relocs -o %t.out
.text
@@ -48,6 +48,13 @@ _fini:
hlt
.size _fini, .-_fini
+ .globl _init
+ .type _init, %function
+ .p2align 4
+_init:
+ retq
+ .size _init, .-_init
+
.data
.globl var
var:
diff --git a/bolt/test/runtime/X86/instrument-wrong-target.s b/bolt/test/runtime/X86/instrument-wrong-target.s
index 343d93a89ed13..fa40d43f10a0f 100644
--- a/bolt/test/runtime/X86/instrument-wrong-target.s
+++ b/bolt/test/runtime/X86/instrument-wrong-target.s
@@ -19,6 +19,13 @@ _start:
ret
.size _start, .-_start
+ .globl _init
+ .type _init, %function
+ # Force DT_INIT to be created (needed for instrumentation).
+_init:
+ ret
+ .size _init, .-_init
+
.globl _fini
.type _fini, %function
# Force DT_FINI to be created (needed for instrumentation).
>From 927c1579f466fb2e63839573fa975d24d36ad6c6 Mon Sep 17 00:00:00 2001
From: Vasily Leonenko <vasily.leonenko at huawei.com>
Date: Tue, 25 Nov 2025 09:53:36 -0500
Subject: [PATCH 4/6] [BOLT] Update updateRtFiniReloc to return error instead
of assertions
---
bolt/include/bolt/Rewrite/RewriteInstance.h | 2 +-
bolt/lib/Rewrite/RewriteInstance.cpp | 23 +++++++++++++--------
2 files changed, 15 insertions(+), 10 deletions(-)
diff --git a/bolt/include/bolt/Rewrite/RewriteInstance.h b/bolt/include/bolt/Rewrite/RewriteInstance.h
index 6b2a0143bbc42..5950b3c1630e1 100644
--- a/bolt/include/bolt/Rewrite/RewriteInstance.h
+++ b/bolt/include/bolt/Rewrite/RewriteInstance.h
@@ -109,7 +109,7 @@ class RewriteInstance {
/// If DT_FINI_ARRAY is used for instrumentation, update the relocation of its
/// first entry to point to the instrumentation library's fini address.
- void updateRtFiniReloc();
+ Error updateRtFiniReloc();
/// Create and initialize metadata rewriters for this instance.
void initializeMetadataManager();
diff --git a/bolt/lib/Rewrite/RewriteInstance.cpp b/bolt/lib/Rewrite/RewriteInstance.cpp
index 8a7800cadbb7e..679268bb75367 100644
--- a/bolt/lib/Rewrite/RewriteInstance.cpp
+++ b/bolt/lib/Rewrite/RewriteInstance.cpp
@@ -813,7 +813,8 @@ Error RewriteInstance::run() {
if (opts::Instrument && !BC->IsStaticExecutable) {
if (Error E = updateRtInitReloc())
return E;
- updateRtFiniReloc();
+ if (Error E = updateRtFiniReloc())
+ return E;
}
if (opts::OutputFilename == "/dev/null") {
@@ -1592,26 +1593,29 @@ Error RewriteInstance::updateRtInitReloc() {
return Error::success();
}
-void RewriteInstance::updateRtFiniReloc() {
+Error RewriteInstance::updateRtFiniReloc() {
// Updating DT_FINI is handled by patchELFDynamic.
if (BC->FiniAddress)
- return;
+ return Error::success();
const RuntimeLibrary *RT = BC->getRuntimeLibrary();
if (!RT || !RT->getRuntimeFiniAddress())
- return;
+ return Error::success();
- assert(BC->FiniArrayAddress && BC->FiniArraySize &&
- "inconsistent .fini_array state");
+ if (!BC->FiniArrayAddress || !BC->FiniArraySize)
+ return createStringError(std::errc::not_supported,
+ "inconsistent .fini_array state");
ErrorOr<BinarySection &> FiniArraySection =
BC->getSectionForAddress(*BC->FiniArrayAddress);
- assert(FiniArraySection && ".fini_array removed");
+ if (!FiniArraySection)
+ return createStringError(std::errc::not_supported, ".fini_array removed");
if (std::optional<Relocation> Reloc =
FiniArraySection->takeDynamicRelocationAt(0)) {
- assert(Reloc->Addend == BC->FiniFunctionAddress &&
- "inconsistent .fini_array dynamic relocation");
+ if (Reloc->Addend != BC->FiniFunctionAddress)
+ return createStringError(std::errc::not_supported,
+ "inconsistent .fini_array dynamic relocation");
Reloc->Addend = RT->getRuntimeFiniAddress();
FiniArraySection->addDynamicRelocation(*Reloc);
}
@@ -1624,6 +1628,7 @@ void RewriteInstance::updateRtFiniReloc() {
FiniArraySection->addPendingRelocation(Relocation{
/*Offset*/ 0, /*Symbol*/ nullptr, /*Type*/ Relocation::getAbs64(),
/*Addend*/ RT->getRuntimeFiniAddress(), /*Value*/ 0});
+ return Error::success();
}
void RewriteInstance::registerFragments() {
>From d756b98d4362b56c212c88a13b8fe4823b8db224 Mon Sep 17 00:00:00 2001
From: Vasily Leonenko <vasily.leonenko at huawei.com>
Date: Wed, 19 Nov 2025 21:48:03 +0300
Subject: [PATCH 5/6] [BOLT] Print information about hooking methods for
runtime library init/fini
Also extend hook-init & hook-fini tests with corresponding bolt output checks.
---
bolt/lib/Rewrite/RewriteInstance.cpp | 36 ++++++++++++++++++++++++----
bolt/test/AArch64/hook-fini.s | 14 ++++++++---
bolt/test/AArch64/hook-init.s | 31 +++++++++++++++++-------
bolt/test/X86/hook-init.s | 25 +++++++++++++++----
4 files changed, 85 insertions(+), 21 deletions(-)
diff --git a/bolt/lib/Rewrite/RewriteInstance.cpp b/bolt/lib/Rewrite/RewriteInstance.cpp
index 679268bb75367..c4d39c2f3a607 100644
--- a/bolt/lib/Rewrite/RewriteInstance.cpp
+++ b/bolt/lib/Rewrite/RewriteInstance.cpp
@@ -1590,6 +1590,10 @@ Error RewriteInstance::updateRtInitReloc() {
InitArraySection->addPendingRelocation(Relocation{
/*Offset*/ 0, /*Symbol*/ nullptr, /*Type*/ Relocation::getAbs64(),
/*Addend*/ RT->getRuntimeStartAddress(), /*Value*/ 0});
+ BC->outs()
+ << "BOLT-INFO: runtime library initialization was hooked via .init_array "
+ "entry, set to 0x"
+ << Twine::utohexstr(RT->getRuntimeStartAddress()) << "\n";
return Error::success();
}
@@ -1628,6 +1632,9 @@ Error RewriteInstance::updateRtFiniReloc() {
FiniArraySection->addPendingRelocation(Relocation{
/*Offset*/ 0, /*Symbol*/ nullptr, /*Type*/ Relocation::getAbs64(),
/*Addend*/ RT->getRuntimeFiniAddress(), /*Value*/ 0});
+ BC->outs() << "BOLT-INFO: runtime library finalization was hooked via "
+ ".fini_array entry, set to 0x"
+ << Twine::utohexstr(RT->getRuntimeFiniAddress()) << "\n";
return Error::success();
}
@@ -2327,6 +2334,14 @@ void RewriteInstance::adjustCommandLineOptions() {
exit(1);
}
+ if (opts::Instrument && opts::RuntimeLibInitHook == opts::RLIH_ENTRY_POINT &&
+ !BC->HasInterpHeader) {
+ BC->errs()
+ << "BOLT-WARNING: adjusted runtime-lib-init-hook to 'init' due to "
+ "absence of INTERP header\n";
+ opts::RuntimeLibInitHook = opts::RLIH_INIT;
+ }
+
if (opts::HotText && opts::HotTextMoveSections.getNumOccurrences() == 0) {
opts::HotTextMoveSections.addValue(".stub");
opts::HotTextMoveSections.addValue(".mover");
@@ -4999,9 +5014,13 @@ void RewriteInstance::patchELFSectionHeaderTable(ELFObjectFile<ELFT> *File) {
if (BC->HasRelocations) {
RuntimeLibrary *RtLibrary = BC->getRuntimeLibrary();
- if (RtLibrary && opts::RuntimeLibInitHook == opts::RLIH_ENTRY_POINT)
+ if (RtLibrary && opts::RuntimeLibInitHook == opts::RLIH_ENTRY_POINT) {
NewEhdr.e_entry = RtLibrary->getRuntimeStartAddress();
- else
+ BC->outs()
+ << "BOLT-INFO: runtime library initialization was hooked via ELF "
+ "Header Entry Point, set to 0x"
+ << Twine::utohexstr(NewEhdr.e_entry) << "\n";
+ } else
NewEhdr.e_entry = getNewFunctionAddress(NewEhdr.e_entry);
assert((NewEhdr.e_entry || !Obj.getHeader().e_entry) &&
"cannot find new address for entry point");
@@ -5842,16 +5861,23 @@ void RewriteInstance::patchELFDynamic(ELFObjectFile<ELFT> *File) {
}
RuntimeLibrary *RtLibrary = BC->getRuntimeLibrary();
if (RtLibrary && Dyn.getTag() == ELF::DT_FINI) {
- if (uint64_t Addr = RtLibrary->getRuntimeFiniAddress())
+ if (uint64_t Addr = RtLibrary->getRuntimeFiniAddress()) {
NewDE.d_un.d_ptr = Addr;
+ BC->outs()
+ << "BOLT-INFO: runtime library finalization was hooked via "
+ "DT_FINI, set to 0x"
+ << Twine::utohexstr(Addr) << "\n";
+ }
}
if (RtLibrary && Dyn.getTag() == ELF::DT_INIT &&
(!BC->HasInterpHeader ||
opts::RuntimeLibInitHook == opts::RLIH_INIT)) {
if (auto Addr = RtLibrary->getRuntimeStartAddress()) {
- LLVM_DEBUG(dbgs() << "BOLT-DEBUG: Set DT_INIT to 0x"
- << Twine::utohexstr(Addr) << '\n');
NewDE.d_un.d_ptr = Addr;
+ BC->outs()
+ << "BOLT-INFO: runtime library initialization was hooked via "
+ "DT_INIT, set to 0x"
+ << Twine::utohexstr(Addr) << "\n";
}
}
break;
diff --git a/bolt/test/AArch64/hook-fini.s b/bolt/test/AArch64/hook-fini.s
index 4f321d463ef32..3bb95f9317b1b 100644
--- a/bolt/test/AArch64/hook-fini.s
+++ b/bolt/test/AArch64/hook-fini.s
@@ -15,13 +15,13 @@
# RUN: %clang %cflags -pie %s -Wl,-q -o %t.exe
# RUN: llvm-readelf -d %t.exe | FileCheck --check-prefix=DYN-FINI %s
# RUN: llvm-readelf -r %t.exe | FileCheck --check-prefix=RELOC-PIE %s
-# RUN: llvm-bolt %t.exe -o %t --instrument
+# RUN: llvm-bolt %t.exe -o %t --instrument | FileCheck --check-prefix=CHECK-BOLT-RT-FINI %s
# RUN: llvm-readelf -drs %t | FileCheck --check-prefix=CHECK-FINI %s
# RUN: %clang %cflags -pie %s -Wl,-q,-fini=0 -o %t-no-fini.exe
# RUN: llvm-readelf -d %t-no-fini.exe | FileCheck --check-prefix=DYN-NO-FINI %s
# RUN: llvm-readelf -r %t-no-fini.exe | FileCheck --check-prefix=RELOC-PIE %s
-# RUN: llvm-bolt %t-no-fini.exe -o %t-no-fini --instrument
+# RUN: llvm-bolt %t-no-fini.exe -o %t-no-fini --instrument | FileCheck --check-prefix=CHECK-BOLT-RT-FINI-ARRAY %s
# RUN: llvm-readelf -drs %t-no-fini | FileCheck --check-prefix=CHECK-NO-FINI %s
# RUN: llvm-readelf -ds -x .fini_array %t-no-fini | FileCheck --check-prefix=CHECK-NO-FINI-RELOC %s
@@ -29,7 +29,7 @@
# RUN: %clang %cflags %p/../Inputs/stub.c -fPIC -shared -o %t-stub.so
# RUN: %clang %cflags %s -no-pie -Wl,-q,-fini=0 %t-stub.so -o %t-no-pie-no-fini.exe
# RUN: llvm-readelf -r %t-no-pie-no-fini.exe | FileCheck --check-prefix=RELOC-NO-PIE %s
-# RUN: llvm-bolt %t-no-pie-no-fini.exe -o %t-no-pie-no-fini --instrument
+# RUN: llvm-bolt %t-no-pie-no-fini.exe -o %t-no-pie-no-fini --instrument | FileCheck --check-prefix=CHECK-BOLT-RT-FINI-ARRAY %s
# RUN: llvm-readelf -ds -x .fini_array %t-no-pie-no-fini | FileCheck --check-prefix=CHECK-NO-PIE-NO-FINI %s
## With fini: dynamic section should contain DT_FINI
@@ -46,6 +46,14 @@
## Without PIE: binary should not have relative relocations
# RELOC-NO-PIE-NOT: R_AARCH64_RELATIVE
+## Check BOLT output output finalization hook (DT_FINI)
+# CHECK-BOLT-RT-FINI: runtime library finalization was hooked via DT_FINI
+# CHECK-BOLT-RT-FINI-NOT: runtime library finalization was hooked via .fini_array entry
+
+## Check BOLT output output finalization hook (.fini_array entry)
+# CHECK-BOLT-RT-FINI-ARRAY-NOT: runtime library finalization was hooked via DT_FINI
+# CHECK-BOLT-RT-FINI-ARRAY: runtime library finalization was hooked via .fini_array entry
+
## Check that DT_FINI is set to __bolt_runtime_fini
# CHECK-FINI: Dynamic section at offset {{.*}} contains {{.*}} entries:
# CHECK-FINI-DAG: (FINI) 0x[[FINI:[[:xdigit:]]+]]
diff --git a/bolt/test/AArch64/hook-init.s b/bolt/test/AArch64/hook-init.s
index e5b11ecae57cc..a48328b630fa0 100644
--- a/bolt/test/AArch64/hook-init.s
+++ b/bolt/test/AArch64/hook-init.s
@@ -18,41 +18,41 @@
# RUN: llvm-readelf -d %t.exe | FileCheck --check-prefix=DYN-INIT %s
# RUN: llvm-readelf -l %t.exe | FileCheck --check-prefix=PH-INTERP %s
# RUN: llvm-readelf -r %t.exe | FileCheck --check-prefix=RELOC-PIE %s
-# RUN: llvm-bolt %t.exe -o %t --instrument
+# RUN: llvm-bolt %t.exe -o %t --instrument | FileCheck --check-prefix=CHECK-BOLT-RT-EP %s
# RUN: llvm-readelf -hdrs %t | FileCheck --check-prefix=CHECK-INIT-EP %s
-# RUN: llvm-bolt %t.exe -o %t-no-ep --instrument --runtime-lib-init-hook=init
+# RUN: llvm-bolt %t.exe -o %t-no-ep --instrument --runtime-lib-init-hook=init | FileCheck --check-prefix=CHECK-BOLT-RT-INIT %s
# RUN: llvm-readelf -hdrs %t-no-ep | FileCheck --check-prefix=CHECK-INIT-NO-EP %s
-# RUN: llvm-bolt %t.exe -o %t-no-ep --instrument --runtime-lib-init-hook=init_array
+# RUN: llvm-bolt %t.exe -o %t-no-ep --instrument --runtime-lib-init-hook=init_array | FileCheck --check-prefix=CHECK-BOLT-RT-INIT-ARRAY %s
# RUN: llvm-readelf -hdrs %t-no-ep | FileCheck --check-prefix=CHECK-INIT-ARRAY-NO-EP %s
# RUN: %clang -shared %cflags -pie %s -Wl,-q -o %t-shared.exe
# RUN: llvm-readelf -d %t-shared.exe | FileCheck --check-prefix=DYN-INIT %s
# RUN: llvm-readelf -l %t-shared.exe | FileCheck --check-prefix=PH-INTERP-SHARED %s
# RUN: llvm-readelf -r %t-shared.exe | FileCheck --check-prefix=RELOC-SHARED-PIE %s
-# RUN: llvm-bolt %t-shared.exe -o %t-shared --instrument
+# RUN: llvm-bolt %t-shared.exe -o %t-shared --instrument | FileCheck --check-prefix=CHECK-BOLT-RT-INIT %s
# RUN: llvm-readelf -hdrs %t-shared | FileCheck --check-prefix=CHECK-SHARED-INIT %s
# RUN: %clang %cflags -pie %s -Wl,-q,-init=0 -o %t-no-init.exe
# RUN: llvm-readelf -d %t-no-init.exe | FileCheck --check-prefix=DYN-NO-INIT %s
# RUN: llvm-readelf -l %t-no-init.exe | FileCheck --check-prefix=PH-INTERP %s
# RUN: llvm-readelf -r %t-no-init.exe | FileCheck --check-prefix=RELOC-PIE %s
-# RUN: llvm-bolt %t-no-init.exe -o %t-no-init --instrument
+# RUN: llvm-bolt %t-no-init.exe -o %t-no-init --instrument | FileCheck --check-prefix=CHECK-BOLT-RT-EP %s
# RUN: llvm-readelf -hdrs %t-no-init | FileCheck --check-prefix=CHECK-NO-INIT-EP %s
-# RUN: llvm-bolt %t-no-init.exe -o %t-no-init-no-ep --instrument --runtime-lib-init-hook=init
+# RUN: llvm-bolt %t-no-init.exe -o %t-no-init-no-ep --instrument --runtime-lib-init-hook=init | FileCheck --check-prefix=CHECK-BOLT-RT-INIT-ARRAY %s
# RUN: llvm-readelf -hdrs %t-no-init-no-ep | FileCheck --check-prefix=CHECK-NO-INIT-NO-EP %s
# RUN: %clang -shared %cflags -pie %s -Wl,-q,-init=0 -o %t-shared-no-init.exe
# RUN: llvm-readelf -d %t-shared-no-init.exe | FileCheck --check-prefix=DYN-NO-INIT %s
# RUN: llvm-readelf -l %t-shared-no-init.exe | FileCheck --check-prefix=PH-INTERP-SHARED %s
# RUN: llvm-readelf -r %t-shared-no-init.exe | FileCheck --check-prefix=RELOC-SHARED-PIE %s
-# RUN: llvm-bolt %t-shared-no-init.exe -o %t-shared-no-init --instrument
+# RUN: llvm-bolt %t-shared-no-init.exe -o %t-shared-no-init --instrument | FileCheck --check-prefix=CHECK-BOLT-RT-INIT-ARRAY %s
# RUN: llvm-readelf -drs %t-shared-no-init | FileCheck --check-prefix=CHECK-SHARED-NO-INIT %s
## Create a dummy shared library to link against to force creation of the dynamic section.
# RUN: %clang %cflags %p/../Inputs/stub.c -fPIC -shared -o %t-stub.so
# RUN: %clang %cflags %s -no-pie -Wl,-q,-init=0 %t-stub.so -o %t-no-pie-no-init.exe
# RUN: llvm-readelf -r %t-no-pie-no-init.exe | FileCheck --check-prefix=RELOC-NO-PIE %s
-# RUN: llvm-bolt %t-no-pie-no-init.exe -o %t-no-pie-no-init --instrument
+# RUN: llvm-bolt %t-no-pie-no-init.exe -o %t-no-pie-no-init --instrument | FileCheck --check-prefix=CHECK-BOLT-RT-EP %s
# RUN: llvm-readelf -hds %t-no-pie-no-init | FileCheck --check-prefix=CHECK-NO-PIE-NO-INIT-EP %s
## With init: dynamic section should contain DT_INIT
@@ -80,6 +80,21 @@
## Without PIE: binary should not have relative relocations
# RELOC-NO-PIE-NOT: R_AARCH64_RELATIVE
+## Check BOLT output output initialization hook (ELF Header Entry Point)
+# CHECK-BOLT-RT-EP: runtime library initialization was hooked via ELF Header Entry Point
+# CHECK-BOLT-RT-EP-NOT: runtime library initialization was hooked via DT_INIT
+# CHECK-BOLT-RT-EP-NOT: runtime library initialization was hooked via .init_array entry
+
+## Check BOLT output output initialization hook (DT_INIT)
+# CHECK-BOLT-RT-INIT-NOT: runtime library initialization was hooked via ELF Header Entry Point
+# CHECK-BOLT-RT-INIT: runtime library initialization was hooked via DT_INIT
+# CHECK-BOLT-RT-INIT-NOT: runtime library initialization was hooked via .init_array entry
+
+## Check BOLT output output initialization hook (.init_array entry)
+# CHECK-BOLT-RT-INIT-ARRAY-NOT: runtime library initialization was hooked via ELF Header Entry Point
+# CHECK-BOLT-RT-INIT-ARRAY-NOT: runtime library initialization was hooked via DT_INIT
+# CHECK-BOLT-RT-INIT-ARRAY: runtime library initialization was hooked via .init_array entry
+
## Check that entry point address is set to __bolt_runtime_start for PIE executable with DT_INIT
# CHECK-INIT-EP: ELF Header:
# CHECK-INIT-EP: Entry point address: 0x[[#%x,EP_ADDR:]]
diff --git a/bolt/test/X86/hook-init.s b/bolt/test/X86/hook-init.s
index 0c96bc7f95bcd..3184541f040b9 100644
--- a/bolt/test/X86/hook-init.s
+++ b/bolt/test/X86/hook-init.s
@@ -20,9 +20,9 @@
# RUN: llvm-readelf -r %t.exe | FileCheck --check-prefix=RELOC-PIE %s
# RUN: llvm-bolt %t.exe -o %t --instrument | FileCheck --check-prefix=CHECK-BOLT-RT-EP %s
# RUN: llvm-readelf -hdrs %t | FileCheck --check-prefix=CHECK-INIT-EP %s
-# RUN: llvm-bolt %t.exe -o %t-no-ep --instrument --runtime-lib-init-hook=init
+# RUN: llvm-bolt %t.exe -o %t-no-ep --instrument --runtime-lib-init-hook=init | FileCheck --check-prefix=CHECK-BOLT-RT-INIT %s
# RUN: llvm-readelf -hdrs %t-no-ep | FileCheck --check-prefix=CHECK-INIT-NO-EP %s
-# RUN: llvm-bolt %t.exe -o %t-no-ep --instrument --runtime-lib-init-hook=init_array
+# RUN: llvm-bolt %t.exe -o %t-no-ep --instrument --runtime-lib-init-hook=init_array | FileCheck --check-prefix=CHECK-BOLT-RT-INIT-ARRAY %s
# RUN: llvm-readelf -hdrs %t-no-ep | FileCheck --check-prefix=CHECK-INIT-ARRAY-NO-EP %s
# RUN: %clang -shared %cflags -pie %s -Wl,-q -o %t-shared.exe
@@ -38,21 +38,21 @@
# RUN: llvm-readelf -r %t-no-init.exe | FileCheck --check-prefix=RELOC-PIE %s
# RUN: llvm-bolt %t-no-init.exe -o %t-no-init --instrument | FileCheck --check-prefix=CHECK-BOLT-RT-EP %s
# RUN: llvm-readelf -hdrs %t-no-init | FileCheck --check-prefix=CHECK-NO-INIT-EP %s
-# RUN: llvm-bolt %t-no-init.exe -o %t-no-init-no-ep --instrument --runtime-lib-init-hook=init
+# RUN: llvm-bolt %t-no-init.exe -o %t-no-init-no-ep --instrument --runtime-lib-init-hook=init | FileCheck --check-prefix=CHECK-BOLT-RT-INIT-ARRAY %s
# RUN: llvm-readelf -hdrs %t-no-init-no-ep | FileCheck --check-prefix=CHECK-NO-INIT-NO-EP %s
# RUN: %clang -shared %cflags -pie %s -Wl,-q,-init=0 -o %t-shared-no-init.exe
# RUN: llvm-readelf -d %t-shared-no-init.exe | FileCheck --check-prefix=DYN-NO-INIT %s
# RUN: llvm-readelf -l %t-shared-no-init.exe | FileCheck --check-prefix=PH-INTERP-SHARED %s
# RUN: llvm-readelf -r %t-shared-no-init.exe | FileCheck --check-prefix=RELOC-SHARED-PIE %s
-# RUN: llvm-bolt %t-shared-no-init.exe -o %t-shared-no-init --instrument
+# RUN: llvm-bolt %t-shared-no-init.exe -o %t-shared-no-init --instrument | FileCheck --check-prefix=CHECK-BOLT-RT-INIT-ARRAY %s
# RUN: llvm-readelf -drs %t-shared-no-init | FileCheck --check-prefix=CHECK-SHARED-NO-INIT %s
## Create a dummy shared library to link against to force creation of the dynamic section.
# RUN: %clang %cflags %p/../Inputs/stub.c -fPIC -shared -o %t-stub.so
# RUN: %clang %cflags %s -no-pie -Wl,-q,-init=0 %t-stub.so -o %t-no-pie-no-init.exe
# RUN: llvm-readelf -r %t-no-pie-no-init.exe | FileCheck --check-prefix=RELOC-NO-PIE %s
-# RUN: llvm-bolt %t-no-pie-no-init.exe -o %t-no-pie-no-init --instrument
+# RUN: llvm-bolt %t-no-pie-no-init.exe -o %t-no-pie-no-init --instrument | FileCheck --check-prefix=CHECK-BOLT-RT-EP %s
# RUN: llvm-readelf -hds %t-no-pie-no-init | FileCheck --check-prefix=CHECK-NO-PIE-NO-INIT-EP %s
## With init: dynamic section should contain DT_INIT
@@ -80,6 +80,21 @@
## Without PIE: binary should not have relative relocations
# RELOC-NO-PIE-NOT: R_X86_64_RELATIVE
+## Check BOLT output output initialization hook (ELF Header Entry Point)
+# CHECK-BOLT-RT-EP: runtime library initialization was hooked via ELF Header Entry Point
+# CHECK-BOLT-RT-EP-NOT: runtime library initialization was hooked via DT_INIT
+# CHECK-BOLT-RT-EP-NOT: runtime library initialization was hooked via .init_array entry
+
+## Check BOLT output output initialization hook (DT_INIT)
+# CHECK-BOLT-RT-INIT-NOT: runtime library initialization was hooked via ELF Header Entry Point
+# CHECK-BOLT-RT-INIT: runtime library initialization was hooked via DT_INIT
+# CHECK-BOLT-RT-INIT-NOT: runtime library initialization was hooked via .init_array entry
+
+## Check BOLT output output initialization hook (1st entry of .init_array)
+# CHECK-BOLT-RT-INIT-ARRAY-NOT: runtime library initialization was hooked via ELF Header Entry Point
+# CHECK-BOLT-RT-INIT-ARRAY-NOT: runtime library initialization was hooked via DT_INIT
+# CHECK-BOLT-RT-INIT-ARRAY: runtime library initialization was hooked via .init_array entry
+
## Check that entry point address is set to __bolt_runtime_start for PIE executable with DT_INIT
# CHECK-INIT-EP: ELF Header:
# CHECK-INIT-EP: Entry point address: 0x[[#%x,EP_ADDR:]]
>From 2b99f72b5e40455808c44e941a4639720c1d7d8f Mon Sep 17 00:00:00 2001
From: Vasily Leonenko <vasiliy.leonenko at gmail.com>
Date: Thu, 27 Nov 2025 10:43:18 +0300
Subject: [PATCH 6/6] [BOLT] validate init/fini section address in
discoverRtInitAddres/discoverRtFiniAddress
---
bolt/lib/Rewrite/RewriteInstance.cpp | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/bolt/lib/Rewrite/RewriteInstance.cpp b/bolt/lib/Rewrite/RewriteInstance.cpp
index c4d39c2f3a607..1c6244b2d2bf8 100644
--- a/bolt/lib/Rewrite/RewriteInstance.cpp
+++ b/bolt/lib/Rewrite/RewriteInstance.cpp
@@ -1466,6 +1466,11 @@ Error RewriteInstance::discoverRtInitAddress() {
if (auto EC = InitArraySection.getError())
return errorCodeToError(EC);
+ if (InitArraySection->getAddress() != *BC->InitArrayAddress) {
+ return createStringError(std::errc::not_supported,
+ "Inconsistent address of .init_array section");
+ }
+
if (const Relocation *Reloc = InitArraySection->getDynamicRelocationAt(0)) {
if (Reloc->isRelative()) {
BC->StartFunctionAddress = Reloc->Addend;
@@ -1517,6 +1522,11 @@ Error RewriteInstance::discoverRtFiniAddress() {
if (auto EC = FiniArraySection.getError())
return errorCodeToError(EC);
+ if (FiniArraySection->getAddress() != *BC->FiniArrayAddress) {
+ return createStringError(std::errc::not_supported,
+ "Inconsistent address of .fini_array section");
+ }
+
if (const Relocation *Reloc = FiniArraySection->getDynamicRelocationAt(0)) {
BC->FiniFunctionAddress = Reloc->Addend;
return Error::success();
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