[ELF] Don't rely on Symbols.h's transitive inclusion of InputFiles.h. NFC

[ELF] Clean up headers. NFC

[ELF][Mips] Use R_DTPREL for R_MIPS_TLS_DTPREL*

[ELF] Replace noneRel = R_*_NONE with static constexpr. NFC

All architectures define R_*_NONE to 0.

[ELF] Default gotBaseSymInGotPlt to false (NFC for most architectures)

Most architectures use .got instead of .got.plt, so switching the default can
minimize customization.

This fixes an issue for

[ELF] Default gotBaseSymInGotPlt to false (NFC for most architectures)

Most architectures use .got instead of .got.plt, so switching the default can
minimize customization.

This fixes an issue for SPARC V9 which uses .got .
AVR, AMDGPU, and MSP430 don't seem to use _GLOBAL_OFFSET_TABLE_.

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[ELF] Check the Elf_Rel addends for dynamic relocations

There used to be many cases where addends for Elf_Rel were not emitted in
the final object file (mostly when building for MIPS64 since the inp

[ELF] Check the Elf_Rel addends for dynamic relocations

There used to be many cases where addends for Elf_Rel were not emitted in
the final object file (mostly when building for MIPS64 since the input .o
files use RELA but the output uses REL). These cases have been fixed since,
but this patch adds a check to ensure that the written values are correct.
It is based on a previous patch that I added to the CHERI fork of LLD since
we were using MIPS64 as a baseline. The work has now almost entirely
shifted to RISC-V and Arm Morello (which use Elf_Rela), but I thought
it would be useful to upstream our local changes anyway.

This patch adds a (hidden) command line flag --check-dynamic-relocations
that can be used to enable these checks. It is also on by default in
assertions builds for targets that handle all dynamic relocations kinds
that LLD can emit in Target::getImplicitAddend(). Currently this is
enabled for ARM, MIPS, and I386.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D101450

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[ELF] Rename R_TLS to R_TPREL and R_NEG_TLS to R_TPREL_NEG. NFC

The scope of R_TLS (TP offset relocation types (TPREL/TPOFF) used for the
local-exec TLS model) is actually narrower than its name may

[ELF] Rename R_TLS to R_TPREL and R_NEG_TLS to R_TPREL_NEG. NFC

The scope of R_TLS (TP offset relocation types (TPREL/TPOFF) used for the
local-exec TLS model) is actually narrower than its name may imply. R_TLS_NEG
is only used by Solaris R_386_TLS_LE_32.

Rename them so that they will be less confusing.

Reviewed By: grimar, psmith, rprichard

Differential Revision: https://reviews.llvm.org/D93467

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[lib/Object] - Refine interface of ELFFile<ELFT>. NFCI.

`ELFFile<ELFT>` has many methods that take pointers,
though they assume that arguments are never null and
hence could take references instead.

[lib/Object] - Refine interface of ELFFile<ELFT>. NFCI.

`ELFFile<ELFT>` has many methods that take pointers,
though they assume that arguments are never null and
hence could take references instead.

This patch performs such clean-up.

Differential revision: https://reviews.llvm.org/D87385

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[ELF] Use namespace qualifiers (lld:: or elf::) instead of `namespace lld { namespace elf {`

Similar to D74882. This reverts much code from commit
bd8cfe65f5fee4ad573adc2172359c9552e8cdc0 (D68323) a

[ELF] Use namespace qualifiers (lld:: or elf::) instead of `namespace lld { namespace elf {`

Similar to D74882. This reverts much code from commit
bd8cfe65f5fee4ad573adc2172359c9552e8cdc0 (D68323) and fixes some
problems before D68323.

Sorry for the churn but D68323 was a mistake. Namespace qualifiers avoid
bugs where the definition does not match the declaration from the
header. See
https://llvm.org/docs/CodingStandards.html#use-namespace-qualifiers-to-implement-previously-declared-functions (D74515)

Differential Revision: https://reviews.llvm.org/D79982

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[ELF] Rename relocateOne() to relocate() and pass `Relocation` to it

Symbol information can be used to improve out-of-range/misalignment diagnostics.
It also helps R_ARM_CALL/R_ARM_THM_CALL which ha

[ELF] Rename relocateOne() to relocate() and pass `Relocation` to it

Symbol information can be used to improve out-of-range/misalignment diagnostics.
It also helps R_ARM_CALL/R_ARM_THM_CALL which has different behaviors with different symbol types.

There are many (67) relocateOne() call sites used in thunks, {Arm,AArch64}errata, PLT, etc.
Rename them to `relocateNoSym()` to be clearer that there is no symbol information.

Reviewed By: grimar, peter.smith

Differential Revision: https://reviews.llvm.org/D73254

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[ELF] writePlt, writeIplt: replace parameters gotPltEntryAddr and index with `const Symbol &`. NFC

PPC::writeIplt (IPLT code sequence, D71621) needs to access `Symbol`.

Reviewed By: grimar, ruiu

D

[ELF] writePlt, writeIplt: replace parameters gotPltEntryAddr and index with `const Symbol &`. NFC

PPC::writeIplt (IPLT code sequence, D71621) needs to access `Symbol`.

Reviewed By: grimar, ruiu

Differential Revision: https://reviews.llvm.org/D71631

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[ELF] Delete relOff from TargetInfo::writePLT

This change only affects EM_386. relOff can be computed from `index`
easily, so it is unnecessarily passed as a parameter.

Both in.plt and in.iplt entr

[ELF] Delete relOff from TargetInfo::writePLT

This change only affects EM_386. relOff can be computed from `index`
easily, so it is unnecessarily passed as a parameter.

Both in.plt and in.iplt entries are written by writePLT. For in.iplt,
the instruction `push reloc_offset` will change because `index` is now
different. Fortunately, this does not matter because `push; jmp` is only
used by PLT. IPLT does not need the code sequence.

Reviewed By: grimar, ruiu

Differential Revision: https://reviews.llvm.org/D71518

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[ELF][AArch64] Support R_AARCH64_{CALL26,JUMP26} range extension thunks with addends

Fixes AArch64 part of PR40438

The current range extension thunk framework does not handle a relocation
relative

[ELF][AArch64] Support R_AARCH64_{CALL26,JUMP26} range extension thunks with addends

Fixes AArch64 part of PR40438

The current range extension thunk framework does not handle a relocation
relative to a STT_SECTION symbol with a non-zero addend, which may be
used by jumps/calls to local functions on some RELA targets (AArch64,
powerpc ELFv1, powerpc64 ELFv2, etc). See PR40438 and the following
code for examples:

// clang -target $target a.cc
// .text.cold may be placed in a separate output section.
// The distance between bar in .text.cold and foo in .text may be larger than 128MiB.
static void foo() {}
__attribute__((section(".text.cold"))) static int bar() { foo(); return
0; }
__attribute__((used)) static int dummy = bar();

This patch makes such thunks with addends work for AArch64. The target
independent part can be reused by PPC in the future.

On REL targets (ARM, MIPS), jumps/calls are not represented as
STT_SECTION + non-zero addend (see
MCELFObjectTargetWriter::needsRelocateWithSymbol), so they don't need
this feature, but we need to make sure this patch does not affect them.

Reviewed By: peter.smith

Differential Revision: https://reviews.llvm.org/D70637

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Ignore R_MIPS_JALR relocations against non-function symbols

Summary:
Current versions of clang would erroneously emit this relocation not only
against functions (loaded from the GOT) but also agains

Ignore R_MIPS_JALR relocations against non-function symbols

Summary:
Current versions of clang would erroneously emit this relocation not only
against functions (loaded from the GOT) but also against data symbols
(e.g. a table of function pointers). LLD was then changing this into a
branch-and-link instruction, causing the program to jump to the data
symbol at run time. I discovered this problem when attempting to boot
MIPS64 FreeBSD after updating the to the latest upstream master.

Reviewers: atanasyan, jrtc27, espindola

Reviewed By: atanasyan

Subscribers: emaste, sdardis, krytarowski, MaskRay, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70406

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[ELF][MIPS] De-template writeValue. NFC

Depends on D68561.

llvm-svn: 373886

[ELF] Wrap things in `namespace lld { namespace elf {`, NFC

This makes it clear `ELF/**/*.cpp` files define things in the `lld::elf`
namespace and simplifies `elf::foo` to `foo`.

Reviewed By: atana

[ELF] Wrap things in `namespace lld { namespace elf {`, NFC

This makes it clear `ELF/**/*.cpp` files define things in the `lld::elf`
namespace and simplifies `elf::foo` to `foo`.

Reviewed By: atanasyan, grimar, ruiu

Differential Revision: https://reviews.llvm.org/D68323

llvm-svn: 373885

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[ELF][MIPS] Use lld::elf::{read,write}* instead of llvm::support::endian::{read,write}*

This allows us to delete `using namespace llvm::support::endian` and
simplify D68323. This change adds runtime

[ELF][MIPS] Use lld::elf::{read,write}* instead of llvm::support::endian::{read,write}*

This allows us to delete `using namespace llvm::support::endian` and
simplify D68323. This change adds runtime config->endianness check but
the overhead should be negligible.

Reviewed By: ruiu

Differential Revision: https://reviews.llvm.org/D68561

llvm-svn: 373884

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[mips] Relax jalr/jr instructions using R_MIPS_JALR relocation

The R_MIPS_JALR relocation denotes jalr/jr instructions in position
independent code. Both these instructions take a target's address f

[mips] Relax jalr/jr instructions using R_MIPS_JALR relocation

The R_MIPS_JALR relocation denotes jalr/jr instructions in position
independent code. Both these instructions take a target's address from
the $25 register. If offset to the target symbol fits into the 18-bits,
it's more efficient to replace jalr/jr by bal/b instructions.

Differential Revision: https://reviews.llvm.org/D68057

llvm-svn: 372951

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[mips] Assign R_TLS type to the R_MIPS_TLS_TPREL_XXX relocations. NFC

That allows to remove duplicated code which subtracts 0x7000 from the
R_MIPS_TLS_TPREL_XXX relocations values in the `MIPS::relo

[mips] Assign R_TLS type to the R_MIPS_TLS_TPREL_XXX relocations. NFC

That allows to remove duplicated code which subtracts 0x7000 from the
R_MIPS_TLS_TPREL_XXX relocations values in the `MIPS::relocateOne`
function.

llvm-svn: 366888

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[Coding style change] Rename variables so that they start with a lowercase letter

This patch is mechanically generated by clang-llvm-rename tool that I wrote
using Clang Refactoring Engine just for

[Coding style change] Rename variables so that they start with a lowercase letter

This patch is mechanically generated by clang-llvm-rename tool that I wrote
using Clang Refactoring Engine just for creating this patch. You can see the
source code of the tool at https://reviews.llvm.org/D64123. There's no manual
post-processing; you can generate the same patch by re-running the tool against
lld's code base.

Here is the main discussion thread to change the LLVM coding style:
https://lists.llvm.org/pipermail/llvm-dev/2019-February/130083.html
In the discussion thread, I proposed we use lld as a testbed for variable
naming scheme change, and this patch does that.

I chose to rename variables so that they are in camelCase, just because that
is a minimal change to make variables to start with a lowercase letter.

Note to downstream patch maintainers: if you are maintaining a downstream lld
repo, just rebasing ahead of this commit would cause massive merge conflicts
because this patch essentially changes every line in the lld subdirectory. But
there's a remedy.

clang-llvm-rename tool is a batch tool, so you can rename variables in your
downstream repo with the tool. Given that, here is how to rebase your repo to
a commit after the mass renaming:

1. rebase to the commit just before the mass variable renaming,
2. apply the tool to your downstream repo to mass-rename variables locally, and
3. rebase again to the head.

Most changes made by the tool should be identical for a downstream repo and
for the head, so at the step 3, almost all changes should be merged and
disappear. I'd expect that there would be some lines that you need to merge by
hand, but that shouldn't be too many.

Differential Revision: https://reviews.llvm.org/D64121

llvm-svn: 365595

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[ELF][ARM][AARCH64][MIPS][PPC] Simplify the logic to create R_*_RELATIVE for absolute relocation types in writable sections

Summary:
Our rule to create R_*_RELATIVE for absolute relocation types wer

[ELF][ARM][AARCH64][MIPS][PPC] Simplify the logic to create R_*_RELATIVE for absolute relocation types in writable sections

Summary:
Our rule to create R_*_RELATIVE for absolute relocation types were
loose. D63121 made it stricter but it failed to create R_*_RELATIVE for
R_ARM_TARGET1 and R_PPC64_TOC. rLLD363236 worked around that by
reinstating the original behavior for ARM and PPC64.

This patch is an attempt to simplify the logic.

Note, in ld.bfd, R_ARM_TARGET2 --target2=abs also creates
R_ARM_RELATIVE. This seems a very uncommon scenario (moreover,
--target2=got-rel is the default), so I do not implement any logic
related to it.

Also, delete R_AARCH64_ABS32 from AArch64::getDynRel. We don't have
working ILP32 support yet. Allowing it would create an incorrect
R_AARCH64_RELATIVE.

For MIPS, the (if SymbolRel, then RelativeRel) code is to keep its
behavior unchanged.

Note, in ppc64-abs64-dyn.s, R_PPC64_TOC gets an incorrect addend because
computeAddend() doesn't compute the correct address. We seem to have the
wrong behavior for a long time. The important thing seems that a dynamic
relocation R_PPC64_TOC should not be created as the dynamic loader will
error R_PPC64_TOC is not supported.

Reviewers: atanasyan, grimar, peter.smith, ruiu, sfertile, espindola

Reviewed By: ruiu

Differential Revision: https://reviews.llvm.org/D63383

llvm-svn: 363928

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[ELF] Make the rule to create relative relocations in a writable section stricter

The current rule is loose: `!Sym.IsPreemptible || Expr == R_GOT`.

When the symbol is non-preemptable, this allows a

[ELF] Make the rule to create relative relocations in a writable section stricter

The current rule is loose: `!Sym.IsPreemptible || Expr == R_GOT`.

When the symbol is non-preemptable, this allows absolute relocation
types with smaller numbers of bits, e.g. R_X86_64_{8,16,32}. They are
disallowed by ld.bfd and gold, e.g.

ld.bfd: a.o: relocation R_X86_64_8 against `.text' can not be used when making a shared object; recompile with -fPIC

This patch:

a) Add TargetInfo::SymbolicRel to represent relocation types that resolve to a
symbol value (e.g. R_AARCH_ABS64, R_386_32, R_X86_64_64).

As a side benefit, we currently (ab)use GotRel (R_*_GLOB_DAT) to resolve
GOT slots that are link-time constants. Since we now use Target->SymbolRel
to do the job, we can remove R_*_GLOB_DAT from relocateOne() for all targets.
R_*_GLOB_DAT cannot be used as static relocation types.
b) Change the condition to `!Sym.IsPreemptible && Type != Target->SymbolicRel || Expr == R_GOT`.

Some tests are caught by the improved error checking (ld.bfd/gold also
issue errors on them). Many misuse .long where .quad should be used
instead.

Reviewed By: ruiu

Differential Revision: https://reviews.llvm.org/D63121

llvm-svn: 363059

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[ELF] Delete GotEntrySize and GotPltEntrySize

GotEntrySize and GotPltEntrySize were added in D22288. Later, with
the introduction of wordsize() (then Config->Wordsize), they become
redundant, becaus

[ELF] Delete GotEntrySize and GotPltEntrySize

GotEntrySize and GotPltEntrySize were added in D22288. Later, with
the introduction of wordsize() (then Config->Wordsize), they become
redundant, because there is no target that sets GotEntrySize or
GotPltEntrySize to a number different from Config->Wordsize.

Reviewed By: grimar, ruiu

Differential Revision: https://reviews.llvm.org/D62727

llvm-svn: 362220

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[mips] Fix ld instruction in PLT entries on MIPS64

Use `ld` and `daddiu` instructions in MIPS64 PLT records. That fixes a
segmentation fault.

Patch by Qiao Pengcheng.

Differential Revision: https:

[mips] Fix ld instruction in PLT entries on MIPS64

Use `ld` and `daddiu` instructions in MIPS64 PLT records. That fixes a
segmentation fault.

Patch by Qiao Pengcheng.

Differential Revision: https://reviews.llvm.org/D61586

llvm-svn: 360187

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ELF: De-template ELFFileBase. NFCI.

Differential Revision: https://reviews.llvm.org/D60304

llvm-svn: 357806