[lld] r356684 - [ELF][ARM] Revert Redesign of .ARM.exidx handling to use a SyntheticSection
Peter Smith via llvm-commits
llvm-commits at lists.llvm.org
Thu Mar 21 10:17:54 PDT 2019
Author: psmith
Date: Thu Mar 21 10:17:54 2019
New Revision: 356684
URL: http://llvm.org/viewvc/llvm-project?rev=356684&view=rev
Log:
[ELF][ARM] Revert Redesign of .ARM.exidx handling to use a SyntheticSection
There is a reproducible buildbot failure (segfault) on the 2 stage
clang-cmake-armv8-lld bot. Reverting while I investigate.
Differential Revision: https://reviews.llvm.org/D59216
Removed:
lld/trunk/test/ELF/arm-exidx-add-missing.s
lld/trunk/test/ELF/arm-exidx-no-add-missing.s
Modified:
lld/trunk/ELF/OutputSections.cpp
lld/trunk/ELF/SyntheticSections.cpp
lld/trunk/ELF/SyntheticSections.h
lld/trunk/ELF/Writer.cpp
lld/trunk/test/ELF/arm-data-prel.s
lld/trunk/test/ELF/arm-exidx-canunwind.s
lld/trunk/test/ELF/arm-exidx-dedup.s
lld/trunk/test/ELF/arm-exidx-gc.s
lld/trunk/test/ELF/arm-exidx-shared.s
Modified: lld/trunk/ELF/OutputSections.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/OutputSections.cpp?rev=356684&r1=356683&r2=356684&view=diff
==============================================================================
--- lld/trunk/ELF/OutputSections.cpp (original)
+++ lld/trunk/ELF/OutputSections.cpp Thu Mar 21 10:17:54 2019
@@ -289,9 +289,7 @@ void OutputSection::finalize() {
// SHF_LINK_ORDER flag. The dependency is indicated by the sh_link field. We
// need to translate the InputSection sh_link to the OutputSection sh_link,
// all InputSections in the OutputSection have the same dependency.
- if (auto *EX = dyn_cast<ARMExidxSyntheticSection>(First))
- Link = EX->getLinkOrderDep()->getParent()->SectionIndex;
- else if (auto *D = First->getLinkOrderDep())
+ if (auto *D = First->getLinkOrderDep())
Link = D->getParent()->SectionIndex;
}
Modified: lld/trunk/ELF/SyntheticSections.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/SyntheticSections.cpp?rev=356684&r1=356683&r2=356684&view=diff
==============================================================================
--- lld/trunk/ELF/SyntheticSections.cpp (original)
+++ lld/trunk/ELF/SyntheticSections.cpp Thu Mar 21 10:17:54 2019
@@ -3052,183 +3052,33 @@ MipsRldMapSection::MipsRldMapSection()
: SyntheticSection(SHF_ALLOC | SHF_WRITE, SHT_PROGBITS, Config->Wordsize,
".rld_map") {}
-ARMExidxSyntheticSection::ARMExidxSyntheticSection()
+ARMExidxSentinelSection::ARMExidxSentinelSection()
: SyntheticSection(SHF_ALLOC | SHF_LINK_ORDER, SHT_ARM_EXIDX,
- Config->Wordsize, ".ARM.exidx") {
- for (InputSectionBase *&IS : InputSections) {
- if (isa<InputSection>(IS) && IS->Type == SHT_ARM_EXIDX) {
- ExidxSections.push_back(cast<InputSection>(IS));
- IS = nullptr;
- } else if (IS->Live && isa<InputSection>(IS) &&
- IS->kind() != SectionBase::Synthetic &&
- (IS->Flags & SHF_ALLOC) && (IS->Flags & SHF_EXECINSTR) &&
- IS->getSize() > 0) {
- ExecutableSections.push_back(cast<InputSection>(IS));
- }
- }
- setSizeAndOffsets();
+ Config->Wordsize, ".ARM.exidx") {}
- std::vector<InputSectionBase *> &V = InputSections;
- V.erase(std::remove(V.begin(), V.end(), nullptr), V.end());
-}
-
-static InputSection *findExidxSection(InputSection *IS) {
- for (InputSection *D : IS->DependentSections)
- if (D->Type == SHT_ARM_EXIDX)
- return D;
- return nullptr;
-}
-
-void ARMExidxSyntheticSection::setSizeAndOffsets() {
- size_t Offset = 0;
- Size = 0;
- for (InputSection *IS : ExecutableSections) {
- if (InputSection *D = findExidxSection(IS)) {
- D->OutSecOff = Offset;
- D->Parent = getParent();
- Offset += D->getSize();
- Empty = false;
- } else {
- Offset += 8;
- }
- }
- // Size includes Sentinel.
- Size = Offset + 8;
-}
-
-// References to .ARM.Extab Sections have bit 31 clear and are not the
-// special EXIDX_CANTUNWIND bit-pattern.
-static bool isExtabRef(uint32_t Unwind) {
- return (Unwind & 0x80000000) == 0 && Unwind != 0x1;
-}
-
-// Return true if the .ARM.exidx section Cur can be merged into the .ARM.exidx
-// section Prev, where Cur follows Prev in the table. This can be done if the
-// unwinding instructions in Cur are identical to Prev. Linker generated
-// EXIDX_CANTUNWIND entries are represented by nullptr as they do not have an
-// InputSection.
-static bool isDuplicateArmExidxSec(InputSection *Prev, InputSection *Cur) {
-
- struct ExidxEntry {
- ulittle32_t Fn;
- ulittle32_t Unwind;
- };
- // Get the last table Entry from the previous .ARM.exidx section. If Prev is
- // nullptr then it will be a synthesized EXIDX_CANTUNWIND entry.
- ExidxEntry PrevEntry = {ulittle32_t(0), ulittle32_t(1)};
- if (Prev)
- PrevEntry = Prev->getDataAs<ExidxEntry>().back();
- if (isExtabRef(PrevEntry.Unwind))
- return false;
-
- // We consider the unwind instructions of an .ARM.exidx table entry
- // a duplicate if the previous unwind instructions if:
- // - Both are the special EXIDX_CANTUNWIND.
- // - Both are the same inline unwind instructions.
- // We do not attempt to follow and check links into .ARM.extab tables as
- // consecutive identical entries are rare and the effort to check that they
- // are identical is high.
-
- // If Cur is nullptr then this is synthesized EXIDX_CANTUNWIND entry.
- if (Cur == nullptr)
- return PrevEntry.Unwind == 1;
-
- for (const ExidxEntry Entry : Cur->getDataAs<ExidxEntry>())
- if (isExtabRef(Entry.Unwind) || Entry.Unwind != PrevEntry.Unwind)
+// Write a terminating sentinel entry to the end of the .ARM.exidx table.
+// This section will have been sorted last in the .ARM.exidx table.
+// This table entry will have the form:
+// | PREL31 upper bound of code that has exception tables | EXIDX_CANTUNWIND |
+// The sentinel must have the PREL31 value of an address higher than any
+// address described by any other table entry.
+void ARMExidxSentinelSection::writeTo(uint8_t *Buf) {
+ assert(Highest);
+ uint64_t S = Highest->getVA(Highest->getSize());
+ uint64_t P = getVA();
+ Target->relocateOne(Buf, R_ARM_PREL31, S - P);
+ write32le(Buf + 4, 1);
+}
+
+// The sentinel has to be removed if there are no other .ARM.exidx entries.
+bool ARMExidxSentinelSection::empty() const {
+ for (InputSection *IS : getInputSections(getParent()))
+ if (!isa<ARMExidxSentinelSection>(IS))
return false;
-
- // All table entries in this .ARM.exidx Section can be merged into the
- // previous Section.
return true;
}
-// The .ARM.exidx table must be sorted in ascending order of the address of the
-// functions the table describes. Optionally duplicate adjacent table entries
-// can be removed. At the end of the function the ExecutableSections must be
-// sorted in ascending order of address, Sentinel is set to the InputSection
-// with the highest address and any InputSections that have mergeable
-// .ARM.exidx table entries are removed from it.
-void ARMExidxSyntheticSection::finalizeContents() {
- // Sort the executable sections that may or may not have associated
- // .ARM.exidx sections by order of ascending address. This requires the
- // relative positions of InputSections to be known.
- auto CompareByFilePosition = [](const InputSection *A,
- const InputSection *B) {
- OutputSection *AOut = A->getParent();
- OutputSection *BOut = B->getParent();
-
- if (AOut != BOut)
- return AOut->SectionIndex < BOut->SectionIndex;
- return A->OutSecOff < B->OutSecOff;
- };
- std::stable_sort(ExecutableSections.begin(), ExecutableSections.end(),
- CompareByFilePosition);
- Sentinel = ExecutableSections.back();
- // Optionally merge adjacent duplicate entries.
- if (Config->MergeArmExidx) {
- std::vector<InputSection *> SelectedSections;
- SelectedSections.reserve(ExecutableSections.size());
- SelectedSections.push_back(ExecutableSections[0]);
- size_t Prev = 0;
- for (size_t I = 1; I < ExecutableSections.size(); ++I) {
- InputSection *EX1 = findExidxSection(ExecutableSections[Prev]);
- InputSection *EX2 = findExidxSection(ExecutableSections[I]);
- if (!isDuplicateArmExidxSec(EX1, EX2)) {
- SelectedSections.push_back(ExecutableSections[I]);
- Prev = I;
- }
- }
- ExecutableSections = std::move(SelectedSections);
- }
- setSizeAndOffsets();
-}
-
-InputSection *ARMExidxSyntheticSection::getLinkOrderDep() const {
- for (InputSection *IS : ExecutableSections)
- if (findExidxSection(IS))
- return IS;
- return nullptr;
-}
-
-// To write the .ARM.exidx table from the ExecutableSections we have three cases
-// 1.) The InputSection has a .ARM.exidx InputSection in its dependent sections.
-// We write the .ARM.exidx section contents and apply its relocations.
-// 2.) The InputSection does not have a dependent .ARM.exidx InputSection. We
-// must write the contents of an EXIDX_CANTUNWIND directly. We use the
-// start of the InputSection as the purpose of the linker generated
-// section is to terminate the address range of the previous entry.
-// 3.) A trailing EXIDX_CANTUNWIND sentinel section is required at the end of
-// the table to terminate the address range of the final entry.
-void ARMExidxSyntheticSection::writeTo(uint8_t *Buf) {
-
- const uint8_t CantUnwindData[8] = {0, 0, 0, 0, // PREL31 to target
- 1, 0, 0, 0}; // EXIDX_CANTUNWIND
-
- uint64_t Offset = 0;
- for (InputSection *IS : ExecutableSections) {
- assert(IS->getParent() != nullptr);
- if (InputSection *D = findExidxSection(IS)) {
- memcpy(Buf + Offset, D->data().data(), D->data().size());
- D->relocateAlloc(Buf, Buf + D->getSize());
- Offset += D->getSize();
- } else {
- // A Linker generated CANTUNWIND section.
- memcpy(Buf + Offset, CantUnwindData, sizeof(CantUnwindData));
- uint64_t S = IS->getVA();
- uint64_t P = getVA() + Offset;
- Target->relocateOne(Buf + Offset, R_ARM_PREL31, S - P);
- Offset += 8;
- }
- }
- // Write Sentinel.
- memcpy(Buf + Offset, CantUnwindData, sizeof(CantUnwindData));
- uint64_t S = Sentinel->getVA(Sentinel->getSize());
- uint64_t P = getVA() + Offset;
- Target->relocateOne(Buf + Offset, R_ARM_PREL31, S - P);
- assert(Size == Offset + 8);
-}
-
-bool ARMExidxSyntheticSection::classof(const SectionBase *D) {
+bool ARMExidxSentinelSection::classof(const SectionBase *D) {
return D->kind() == InputSectionBase::Synthetic && D->Type == SHT_ARM_EXIDX;
}
Modified: lld/trunk/ELF/SyntheticSections.h
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/SyntheticSections.h?rev=356684&r1=356683&r2=356684&view=diff
==============================================================================
--- lld/trunk/ELF/SyntheticSections.h (original)
+++ lld/trunk/ELF/SyntheticSections.h Thu Mar 21 10:17:54 2019
@@ -936,76 +936,19 @@ public:
void writeTo(uint8_t *Buf) override {}
};
-// Representation of the combined .ARM.Exidx input sections. We process these
-// as a SyntheticSection like .eh_frame as we need to merge duplicate entries
-// and add terminating sentinel entries.
-//
-// The .ARM.exidx input sections after SHF_LINK_ORDER processing is done form
-// a table that the unwinder can derive (Addresses are encoded as offsets from
-// table):
-// | Address of function | Unwind instructions for function |
-// where the unwind instructions are either a small number of unwind or the
-// special EXIDX_CANTUNWIND entry representing no unwinding information.
-// When an exception is thrown from an address A, the unwinder searches the
-// table for the closest table entry with Address of function <= A. This means
-// that for two consecutive table entries:
-// | A1 | U1 |
-// | A2 | U2 |
-// The range of addresses described by U1 is [A1, A2)
-//
-// There are two cases where we need a linker generated table entry to fixup
-// the address ranges in the table
-// Case 1:
-// - A sentinel entry added with an address higher than all
-// executable sections. This was needed to work around libunwind bug pr31091.
-// - After address assignment we need to find the highest addressed executable
-// section and use the limit of that section so that the unwinder never
-// matches it.
-// Case 2:
-// - InputSections without a .ARM.exidx section (usually from Assembly)
-// need a table entry so that they terminate the range of the previously
-// function. This is pr40277.
-//
-// Instead of storing pointers to the .ARM.exidx InputSections from
-// InputObjects, we store pointers to the executable sections that need
-// .ARM.exidx sections. We can then use the dependentSections of these to
-// either find the .ARM.exidx section or know that we need to generate one.
-class ARMExidxSyntheticSection : public SyntheticSection {
+class ARMExidxSentinelSection : public SyntheticSection {
public:
- ARMExidxSyntheticSection();
- size_t getSize() const override { return Size; }
+ ARMExidxSentinelSection();
+ size_t getSize() const override { return 8; }
void writeTo(uint8_t *Buf) override;
- bool empty() const override { return Empty; }
- // Sort and remove duplicate entries.
- void finalizeContents() override;
- InputSection *getLinkOrderDep() const;
+ bool empty() const override;
static bool classof(const SectionBase *D);
- // Links to the ARMExidxSections so we can transfer the relocations once the
- // layout is known.
- std::vector<InputSection *> ExidxSections;
-
-private:
- // Derive Size from contents of ExecutableSections, including any linker
- // generated sentinels. Also set the OutSecOff of the ExidxSections.
- void setSizeAndOffsets();
- size_t Size;
-
- // Empty if ExecutableSections contains no dependent .ARM.exidx sections.
- bool Empty = true;
-
- // Instead of storing pointers to the .ARM.exidx InputSections from
- // InputObjects, we store pointers to the executable sections that need
- // .ARM.exidx sections. We can then use the dependentSections of these to
- // either find the .ARM.exidx section or know that we need to generate one.
- std::vector<InputSection *> ExecutableSections;
-
- // The executable InputSection with the highest address to use for the
- // sentinel. We store separately from ExecutableSections as merging of
- // duplicate entries may mean this InputSection is removed from
- // ExecutableSections.
- InputSection *Sentinel = nullptr;
+ // The last section referenced by a regular .ARM.exidx section.
+ // It is found and filled in Writer<ELFT>::resolveShfLinkOrder().
+ // The sentinel points at the end of that section.
+ InputSection *Highest = nullptr;
};
// A container for one or more linker generated thunks. Instances of these
@@ -1060,7 +1003,6 @@ Defined *addSyntheticLocal(StringRef Nam
// Linker generated sections which can be used as inputs.
struct InStruct {
InputSection *ARMAttributes;
- ARMExidxSyntheticSection *ARMExidx;
BssSection *Bss;
BssSection *BssRelRo;
BuildIdSection *BuildId;
Modified: lld/trunk/ELF/Writer.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/Writer.cpp?rev=356684&r1=356683&r2=356684&view=diff
==============================================================================
--- lld/trunk/ELF/Writer.cpp (original)
+++ lld/trunk/ELF/Writer.cpp Thu Mar 21 10:17:54 2019
@@ -435,12 +435,10 @@ template <class ELFT> static void create
if (In.StrTab)
Add(In.StrTab);
- if (Config->EMachine == EM_ARM && !Config->Relocatable) {
- // The ARMExidxsyntheticsection replaces all the individual .ARM.exidx
- // InputSections.
- In.ARMExidx = make<ARMExidxSyntheticSection>();
- Add(In.ARMExidx);
- }
+ if (Config->EMachine == EM_ARM && !Config->Relocatable)
+ // Add a sentinel to terminate .ARM.exidx. It helps an unwinder
+ // to find the exact address range of the last entry.
+ Add(make<ARMExidxSentinelSection>());
}
// The main function of the writer.
@@ -923,9 +921,6 @@ void Writer<ELFT>::forEachRelSec(
Fn(*IS);
for (EhInputSection *ES : In.EhFrame->Sections)
Fn(*ES);
- if (In.ARMExidx)
- for (InputSection *Ex : In.ARMExidx->ExidxSections)
- Fn(*Ex);
}
// This function generates assignments for predefined symbols (e.g. _end or
@@ -1388,6 +1383,11 @@ template <class ELFT> void Writer<ELFT>:
}
static bool compareByFilePosition(InputSection *A, InputSection *B) {
+ // Synthetic, i. e. a sentinel section, should go last.
+ if (A->kind() == InputSectionBase::Synthetic ||
+ B->kind() == InputSectionBase::Synthetic)
+ return A->kind() != InputSectionBase::Synthetic;
+
InputSection *LA = A->getLinkOrderDep();
InputSection *LB = B->getLinkOrderDep();
OutputSection *AOut = LA->getParent();
@@ -1398,6 +1398,53 @@ static bool compareByFilePosition(InputS
return LA->OutSecOff < LB->OutSecOff;
}
+// This function is used by the --merge-exidx-entries to detect duplicate
+// .ARM.exidx sections. It is Arm only.
+//
+// The .ARM.exidx section is of the form:
+// | PREL31 offset to function | Unwind instructions for function |
+// where the unwind instructions are either a small number of unwind
+// instructions inlined into the table entry, the special CANT_UNWIND value of
+// 0x1 or a PREL31 offset into a .ARM.extab Section that contains unwind
+// instructions.
+//
+// We return true if all the unwind instructions in the .ARM.exidx entries of
+// Cur can be merged into the last entry of Prev.
+static bool isDuplicateArmExidxSec(InputSection *Prev, InputSection *Cur) {
+
+ // References to .ARM.Extab Sections have bit 31 clear and are not the
+ // special EXIDX_CANTUNWIND bit-pattern.
+ auto IsExtabRef = [](uint32_t Unwind) {
+ return (Unwind & 0x80000000) == 0 && Unwind != 0x1;
+ };
+
+ struct ExidxEntry {
+ ulittle32_t Fn;
+ ulittle32_t Unwind;
+ };
+
+ // Get the last table Entry from the previous .ARM.exidx section.
+ const ExidxEntry &PrevEntry = Prev->getDataAs<ExidxEntry>().back();
+ if (IsExtabRef(PrevEntry.Unwind))
+ return false;
+
+ // We consider the unwind instructions of an .ARM.exidx table entry
+ // a duplicate if the previous unwind instructions if:
+ // - Both are the special EXIDX_CANTUNWIND.
+ // - Both are the same inline unwind instructions.
+ // We do not attempt to follow and check links into .ARM.extab tables as
+ // consecutive identical entries are rare and the effort to check that they
+ // are identical is high.
+
+ for (const ExidxEntry Entry : Cur->getDataAs<ExidxEntry>())
+ if (IsExtabRef(Entry.Unwind) || Entry.Unwind != PrevEntry.Unwind)
+ return false;
+
+ // All table entries in this .ARM.exidx Section can be merged into the
+ // previous Section.
+ return true;
+}
+
template <class ELFT> void Writer<ELFT>::resolveShfLinkOrder() {
for (OutputSection *Sec : OutputSections) {
if (!(Sec->Flags & SHF_LINK_ORDER))
@@ -1415,17 +1462,46 @@ template <class ELFT> void Writer<ELFT>:
}
}
}
+ std::stable_sort(Sections.begin(), Sections.end(), compareByFilePosition);
- // The ARM.exidx section use SHF_LINK_ORDER, but we have consolidated
- // this processing inside the ARMExidxsyntheticsection::finalizeContents().
if (!Config->Relocatable && Config->EMachine == EM_ARM &&
- Sec->Type == SHT_ARM_EXIDX)
- continue;
+ Sec->Type == SHT_ARM_EXIDX) {
- std::stable_sort(Sections.begin(), Sections.end(), compareByFilePosition);
+ if (auto *Sentinel = dyn_cast<ARMExidxSentinelSection>(Sections.back())) {
+ assert(Sections.size() >= 2 &&
+ "We should create a sentinel section only if there are "
+ "alive regular exidx sections.");
+
+ // The last executable section is required to fill the sentinel.
+ // Remember it here so that we don't have to find it again.
+ Sentinel->Highest = Sections[Sections.size() - 2]->getLinkOrderDep();
+ }
+
+ // The EHABI for the Arm Architecture permits consecutive identical
+ // table entries to be merged. We use a simple implementation that
+ // removes a .ARM.exidx Input Section if it can be merged into the
+ // previous one. This does not require any rewriting of InputSection
+ // contents but misses opportunities for fine grained deduplication
+ // where only a subset of the InputSection contents can be merged.
+ if (Config->MergeArmExidx) {
+ size_t Prev = 0;
+ // The last one is a sentinel entry which should not be removed.
+ for (size_t I = 1; I < Sections.size() - 1; ++I) {
+ if (isDuplicateArmExidxSec(Sections[Prev], Sections[I]))
+ Sections[I] = nullptr;
+ else
+ Prev = I;
+ }
+ }
+ }
for (int I = 0, N = Sections.size(); I < N; ++I)
*ScriptSections[I] = Sections[I];
+
+ // Remove the Sections we marked as duplicate earlier.
+ for (BaseCommand *Base : Sec->SectionCommands)
+ if (auto *ISD = dyn_cast<InputSectionDescription>(Base))
+ llvm::erase_if(ISD->Sections, [](InputSection *IS) { return !IS; });
}
}
@@ -1695,7 +1771,6 @@ template <class ELFT> void Writer<ELFT>:
// Dynamic section must be the last one in this list and dynamic
// symbol table section (DynSymTab) must be the first one.
finalizeSynthetic(In.DynSymTab);
- finalizeSynthetic(In.ARMExidx);
finalizeSynthetic(In.Bss);
finalizeSynthetic(In.BssRelRo);
finalizeSynthetic(In.GnuHashTab);
@@ -1722,8 +1797,8 @@ template <class ELFT> void Writer<ELFT>:
if (!Script->HasSectionsCommand && !Config->Relocatable)
fixSectionAlignments();
- // SHFLinkOrder processing must be processed after relative section placements are
- // known but before addresses are allocated.
+ // After link order processing .ARM.exidx sections can be deduplicated, which
+ // needs to be resolved before any other address dependent operation.
resolveShfLinkOrder();
// Jump instructions in many ISAs have small displacements, and therefore they
Modified: lld/trunk/test/ELF/arm-data-prel.s
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/ELF/arm-data-prel.s?rev=356684&r1=356683&r2=356684&view=diff
==============================================================================
--- lld/trunk/test/ELF/arm-data-prel.s (original)
+++ lld/trunk/test/ELF/arm-data-prel.s Thu Mar 21 10:17:54 2019
@@ -1,8 +1,9 @@
// REQUIRES: arm
-// RUN: llvm-mc %s -triple=armv7-unknown-linux-gnueabi -filetype=obj --arm-add-build-attributes -o %t.o
+// RUN: llvm-mc %s -triple=armv7-unknown-linux-gnueabi -filetype=obj -o %t.o
// RUN: echo "SECTIONS { \
// RUN: .text : { *(.text) } \
// RUN: .prel.test : { *(.ARM.exidx) } \
+// RUN: .prel.test.TEST1 : { *(.ARM.exidx.TEST1) } \
// RUN: .TEST1 : { *(.TEST1) } } " > %t.script
// RUN: ld.lld --script %t.script %t.o -o %t
// RUN: llvm-readobj -s -sd %t | FileCheck --check-prefix=CHECK %s
@@ -46,14 +47,17 @@ __aeabi_unwind_cpp_pr0:
// The expected value of the exception table is
// Word0 0 in bit 31, -4 encoded in 31-bit signed offset
// Word1 Inline table entry EHT Inline Personality Routine #0
-// Word3 0 in bit 31, +10 encoded in 31-bit signed offset
-// Word4 Inline table entry EHT Inline Personality Routine #0
+// CHECK: Name: .prel.test
+// CHECK: SectionData (
+// CHECK: 0000: FCFFFF7F B0B0B080
+// CHECK: )
+
+// The expected value of the exception table is
+// Word0 0 in bit 31, +8 encoded in 31-bit signed offset
+// Word1 Inline table entry EHT Inline Personality Routine #0
// set vsp = r11
// pop r11, r14
-// Word5 Sentinel +18 EXIDX_CANTUNWIND
-
-// CHECK: Name: .prel.test
+// CHECK: Name: .prel.test.TEST1
// CHECK: SectionData (
-// CHECK: 0000: FCFFFF7F B0B0B080 10000000 80849B80
-// CHECK: 0010: 18000000 01000000
+// CHECK: 0000: 08000000 80849B80
// CHECK: )
Removed: lld/trunk/test/ELF/arm-exidx-add-missing.s
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/ELF/arm-exidx-add-missing.s?rev=356683&view=auto
==============================================================================
--- lld/trunk/test/ELF/arm-exidx-add-missing.s (original)
+++ lld/trunk/test/ELF/arm-exidx-add-missing.s (removed)
@@ -1,66 +0,0 @@
-// REQUIRES: arm
-// RUN: llvm-mc -filetype=obj -triple=armv7a-none-linux-gnueabi --arm-add-build-attributes %s -o %t
-// RUN: ld-lld %t --no-merge-exidx-entries -o %t2
-// RUN: llvm-objdump -s %t2 | FileCheck %s
-// RUN: ld-lld %t -o %t3
-// RUN: llvm-objdump -s %t3 | FileCheck %s -check-prefix=CHECK-MERGE
-
-// The ARM.exidx section is a table of 8-byte entries of the form:
-// | PREL31 Relocation to start of function | Unwinding information |
-// The range of addresses covered by the table entry is terminated by the
-// next table entry. This means that an executable section without a .ARM.exidx
-// section does not terminate the range of addresses. To fix this the linker
-// synthesises an EXIDX_CANTUNWIND entry for each section wihout a .ARM.exidx
-// section.
-
- .syntax unified
-
- // Expect inline unwind instructions
- .section .text.01, "ax", %progbits
- .global f1
-f1:
- .fnstart
- bx lr
- .save {r7, lr}
- .setfp r7, sp, #0
- .fnend
-
- // Expect no unwind information from assembler. The linker must
- // synthesise an EXIDX_CANTUNWIND entry to prevent an exception
- // thrown through f2 from matching against the unwind instructions
- // for f1.
- .section .text.02, "ax", %progbits
- .global f2
-f2:
- bx lr
-
-
- // Expect 1 EXIDX_CANTUNWIND entry that can be merged into the linker
- // generated EXIDX_CANTUNWIND as if the assembler had generated it.
- .section .text.03, "ax",%progbits
- .global f3
-f3:
- .fnstart
- bx lr
- .cantunwind
- .fnend
-
- // Dummy implementation of personality routines to satisfy reference
- // from exception tables, linker will generate EXIDX_CANTUNWIND.
- .section .text.__aeabi_unwind_cpp_pr0, "ax", %progbits
- .global __aeabi_unwind_cpp_pr0
-__aeabi_unwind_cpp_pr0:
- bx lr
-
-// f1, f2
-// CHECK: 100d4 2c0f0000 08849780 280f0000 01000000
-// f3, __aeabi_unwind_cpp_pr0
-// CHECK-NEXT: 100e4 240f0000 01000000 200f0000 01000000
-// sentinel
-// CHECK-NEXT: 100f4 1c0f0000 01000000
-
-// f1, (f2, f3, __aeabi_unwind_cpp_pr0)
-// CHECK-MERGE: 100d4 2c0f0000 08849780 280f0000 01000000
-// sentinel
-// CHECK-MERGE-NEXT: 100e4 2c0f0000 01000000
-
Modified: lld/trunk/test/ELF/arm-exidx-canunwind.s
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/ELF/arm-exidx-canunwind.s?rev=356684&r1=356683&r2=356684&view=diff
==============================================================================
--- lld/trunk/test/ELF/arm-exidx-canunwind.s (original)
+++ lld/trunk/test/ELF/arm-exidx-canunwind.s Thu Mar 21 10:17:54 2019
@@ -1,6 +1,6 @@
// REQUIRES: arm
-// RUN: llvm-mc -filetype=obj --arm-add-build-attributes -triple=armv7a-none-linux-gnueabi %s -o %t
-// RUN: ld.lld %t -o %t2
+// RUN: llvm-mc -filetype=obj -triple=armv7a-none-linux-gnueabi %s -o %t
+// RUN: ld.lld %t -o %t2 2>&1
// RUN: llvm-objdump -d -triple=armv7a-none-linux-gnueabi %t2 | FileCheck %s
// RUN: llvm-objdump -s -triple=armv7a-none-linux-gnueabi %t2 | FileCheck -check-prefix=CHECK-EXIDX %s
// RUN: llvm-readobj --program-headers --sections %t2 | FileCheck -check-prefix=CHECK-PT %s
@@ -66,14 +66,15 @@ _start:
// CHECK: __aeabi_unwind_cpp_pr0:
// CHECK-NEXT: 11018: 1e ff 2f e1 bx lr
-// 100d4 + f2c = 11000 = main (linker generated cantunwind)
-// 100dc + f30 = 1100c = func1 (inline unwinding data)
-// CHECK-EXIDX: 100d4 2c0f0000 01000000 300f0000 08849780
-// 100e4 + f2c = 11010 = func2 (100e8 + 14 = 100fc = .ARM.extab entry)
-// 100ec + f28 = 11014 = __gcc_personality_v0 (linker generated cantunwind)
-// CHECK-EXIDX-NEXT: 100e4 2c0f0000 14000000 280f0000 01000000
-// 100f4 + f28 = 1101c = sentinel
-// CHECK-EXIDX-NEXT: 100f4 280f0000 01000000
+// CHECK-EXIDX: Contents of section .ARM.exidx:
+// 100d4 + f38 = 1100c = func1 (inline unwinding data)
+// 100dc + f34 = 11010 = func2 (100e0 + c = 100ec = .ARM.extab entry)
+// CHECK-EXIDX-NEXT: 100d4 380f0000 08849780 340f0000 0c000000
+// 100e4 + f30 = 11014 = terminate = func2 + sizeof(func2)
+// CHECK-EXIDX-NEXT: 100e4 300f0000 01000000
+// CHECK-EXIDX-NEXT: Contents of section .ARM.extab:
+// 100ec + f28 = 11014 = __gxx_personality_v0
+// CHECK-EXIDX-NEXT: 100ec 280f0000 b0b0b000 00000000
// CHECK-PT: Name: .ARM.exidx
// CHECK-PT-NEXT: Type: SHT_ARM_EXIDX (0x70000001)
@@ -83,14 +84,14 @@ _start:
// CHECK-PT-NEXT: ]
// CHECK-PT-NEXT: Address: 0x100D4
// CHECK-PT-NEXT: Offset: 0xD4
-// CHECK-PT-NEXT: Size: 40
+// CHECK-PT-NEXT: Size: 24
// CHECK-PT: Type: PT_ARM_EXIDX (0x70000001)
// CHECK-PT-NEXT: Offset: 0xD4
// CHECK-PT-NEXT: VirtualAddress: 0x100D4
// CHECK-PT-NEXT: PhysicalAddress: 0x100D4
-// CHECK-PT-NEXT: FileSize: 40
-// CHECK-PT-NEXT: MemSize: 40
+// CHECK-PT-NEXT: FileSize: 24
+// CHECK-PT-NEXT: MemSize: 24
// CHECK-PT-NEXT: Flags [ (0x4)
// CHECK-PT-NEXT: PF_R (0x4)
// CHECK-PT-NEXT: ]
Modified: lld/trunk/test/ELF/arm-exidx-dedup.s
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/ELF/arm-exidx-dedup.s?rev=356684&r1=356683&r2=356684&view=diff
==============================================================================
--- lld/trunk/test/ELF/arm-exidx-dedup.s (original)
+++ lld/trunk/test/ELF/arm-exidx-dedup.s Thu Mar 21 10:17:54 2019
@@ -1,29 +1,27 @@
// REQUIRES: arm
-// RUN: llvm-mc -filetype=obj --arm-add-build-attributes -triple=armv7a-none-linux-gnueabi %s -o %t
+// RUN: llvm-mc -filetype=obj -triple=armv7a-none-linux-gnueabi %s -o %t
// RUN: ld.lld %t --no-merge-exidx-entries -o %t2
// RUN: llvm-objdump -s %t2 | FileCheck --check-prefix CHECK-DUPS %s
// RUN: ld.lld %t -o %t3
// RUN: llvm-objdump -s %t3 | FileCheck %s
-
// Test that lld can at least remove duplicate .ARM.exidx sections. A more
// fine grained implementation will be able to remove duplicate entries within
// a .ARM.exidx section.
// With duplicate entries
// CHECK-DUPS: Contents of section .ARM.exidx:
-// CHECK-DUPS-NEXT: 100d4 2c0f0000 01000000 280f0000 01000000
-// CHECK-DUPS-NEXT: 100e4 240f0000 01000000 200f0000 01000000
-// CHECK-DUPS-NEXT: 100f4 1c0f0000 08849780 180f0000 08849780
-// CHECK-DUPS-NEXT: 10104 140f0000 08849780 100f0000 24000000
-// CHECK-DUPS-NEXT: 10114 0c0f0000 28000000 080f0000 01000000
-// CHECK-DUPS-NEXT: 10124 040f0000 01000000 000f0000 01000000
+// CHECK-DUPS-NEXT: 100d4 2c0f0000 01000000 280f0000 01000000
+// CHECK-DUPS-NEXT: 100e4 240f0000 01000000 200f0000 01000000
+// CHECK-DUPS-NEXT: 100f4 1c0f0000 08849780 180f0000 08849780
+// CHECK-DUPS-NEXT: 10104 140f0000 08849780 100f0000 14000000
+// CHECK-DUPS-NEXT: 10114 0c0f0000 18000000 080f0000 01000000
// CHECK-DUPS-NEXT: Contents of section .ARM.extab:
// After duplicate entry removal
// CHECK: Contents of section .ARM.exidx:
-// CHECK-NEXT: 100d4 2c0f0000 01000000 340f0000 08849780
-// CHECK-NEXT: 100e4 380f0000 1c000000 340f0000 20000000
-// CHECK-NEXT: 100f4 300f0000 01000000 300f0000 01000000
+// CHECK-NEXT: 100d4 2c0f0000 01000000 340f0000 08849780
+// CHECK-NEXT: 100e4 380f0000 14000000 340f0000 18000000
+// CHECK-NEXT: 100f4 300f0000 01000000
// CHECK-NEXT: Contents of section .ARM.extab:
.syntax unified
@@ -115,9 +113,8 @@ f8:
.long 0
.fnend
-// Dummy implementation of personality routines to satisfy reference from
-// exception tables
-// Expect Linker generated EXIDX_CANTUNWIND tables
+ // Dummy implementation of personality routines to satisfy reference from
+ // exception tables
.section .text.__gcc_personality_v0, "ax", %progbits
.global __gxx_personality_v0
__gxx_personality_v0:
Modified: lld/trunk/test/ELF/arm-exidx-gc.s
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/ELF/arm-exidx-gc.s?rev=356684&r1=356683&r2=356684&view=diff
==============================================================================
--- lld/trunk/test/ELF/arm-exidx-gc.s (original)
+++ lld/trunk/test/ELF/arm-exidx-gc.s Thu Mar 21 10:17:54 2019
@@ -1,5 +1,5 @@
// REQUIRES: arm
-// RUN: llvm-mc -filetype=obj --arm-add-build-attributes -triple=armv7a-none-linux-gnueabi %s -o %t
+// RUN: llvm-mc -filetype=obj -triple=armv7a-none-linux-gnueabi %s -o %t
// RUN: ld.lld %t --no-merge-exidx-entries -o %t2 --gc-sections 2>&1
// RUN: llvm-objdump -d -triple=armv7a-none-linux-gnueabi %t2 | FileCheck %s
// RUN: llvm-objdump -s -triple=armv7a-none-linux-gnueabi %t2 | FileCheck -check-prefix=CHECK-EXIDX %s
@@ -111,15 +111,14 @@ _start:
// CHECK-NOT: __gxx_personality_v1
// CHECK-EXIDX: Contents of section .ARM.exidx:
-// 100d4 + f2c = 11000
-// 100dc + f30 = 1100c = func1
-// CHECK-EXIDX-NEXT: 100d4 2c0f0000 01000000 300f0000 08849780
-// 100e4 + f2c = 11010 = func2 (100e8 + 1c = 10104 = .ARM.extab)
-// 100ec + f28 = 11014 = __gxx_personality_v0
-// CHECK-EXIDX-NEXT: 100e4 2c0f0000 1c000000 280f0000 01000000
-// 100f4 + f24 = 11018 = __aeabi_unwind_cpp_pr0
-// 100fc + f20 = 1101c = __aeabi_unwind_cpp_pr0 + sizeof(__aeabi_unwind_cpp_pr0)
-// CHECK-EXIDX-NEXT: 100f4 240f0000 01000000 200f0000 01000000
+// 100d4 + f38 = 1100c = func1
+// 100dc + f34 = 11010 = func2 (100e0 + 1c = 100fc = .ARM.extab)
+// CHECK-EXIDX-NEXT: 100d4 380f0000 08849780 340f0000 1c000000
+// 100e4 + f30 = 11014 = __gxx_personality_v0
+// 100ec + f2c = 11018 = __aeabi_unwind_cpp_pr0
+// CHECK-EXIDX-NEXT: 100e4 300f0000 01000000 2c0f0000 01000000
+// 100f4 + f28 = 1101c = __aeabi_unwind_cpp_pr0 + sizeof(__aeabi_unwind_cpp_pr0)
+// CHECK-EXIDX-NEXT: 100f4 280f0000 01000000
// CHECK-EXIDX-NEXT: Contents of section .ARM.extab:
-// 10104 + f10 = 11014 = __gxx_personality_v0
-// CHECK-EXIDX-NEXT: 10104 100f0000 b0b0b000
+// 100fc + f18 = 11014 = __gxx_personality_v0
+// CHECK-EXIDX-NEXT: 100fc 180f0000 b0b0b000
Removed: lld/trunk/test/ELF/arm-exidx-no-add-missing.s
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/ELF/arm-exidx-no-add-missing.s?rev=356683&view=auto
==============================================================================
--- lld/trunk/test/ELF/arm-exidx-no-add-missing.s (original)
+++ lld/trunk/test/ELF/arm-exidx-no-add-missing.s (removed)
@@ -1,16 +0,0 @@
-// REQUIRES: arm
-// RUN: llvm-mc -filetype=obj -triple=armv7a-none-linux-gnueabi --arm-add-build-attributes %s -o %t
-// RUN: ld-lld %t -o %t2
-// RUN: llvm-objdump -s %t2 | FileCheck %s
-
-// We do not want to generate missing EXIDX_CANTUNWIND entries if there are no
-// input .ARM.exidx sections.
-
-// CHECK-NOT: .ARM.exidx
- .syntax unified
- .text
- .globl _start
- .type _start, %function
-_start:
- bx lr
-
Modified: lld/trunk/test/ELF/arm-exidx-shared.s
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/ELF/arm-exidx-shared.s?rev=356684&r1=356683&r2=356684&view=diff
==============================================================================
--- lld/trunk/test/ELF/arm-exidx-shared.s (original)
+++ lld/trunk/test/ELF/arm-exidx-shared.s Thu Mar 21 10:17:54 2019
@@ -1,8 +1,8 @@
// REQUIRES: arm
-// RUN: llvm-mc -filetype=obj -arm-add-build-attributes -triple=armv7a-none-linux-gnueabi %s -o %t
+// RUN: llvm-mc -filetype=obj -triple=armv7a-none-linux-gnueabi %s -o %t
// RUN: ld.lld --hash-style=sysv %t --shared -o %t2 2>&1
// RUN: llvm-readobj --relocations %t2 | FileCheck %s
-// RUN: llvm-objdump -s -triple=armv7a-none-linux-gnueabi %t2 | FileCheck --check-prefix=CHECK-EXTAB-NEXT %s
+// RUN: llvm-objdump -s -triple=armv7a-none-linux-gnueabi %t2 | FileCheck -check-prefix=CHECK-EXTAB %s
// Check that the relative R_ARM_PREL31 relocation can access a PLT entry
// for when the personality routine is referenced from a shared library.
@@ -41,5 +41,5 @@ __aeabi_unwind_cpp_pr0:
// CHECK-NEXT: 0x300C R_ARM_JUMP_SLOT __gxx_personality_v0
// CHECK-EXTAB: Contents of section .ARM.extab:
-// 0x0238 + 0xdf8 = 0x1030 = __gxx_personality_v0(PLT)
-// CHECK-EXTAB-NEXT: 0238 f80d0000 b0b0b000 00000000
+// 0x0210 + 0x0e20 = 0x1030 = __gxx_personality_v0(PLT)
+// CHECK-EXTAB-NEXT: 0230 000e0000 b0b0b000 00000000
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