Commit Graph

5300 Commits

Author SHA1 Message Date
Dimitry Andric c9de3b4d26 Align AArch64 and i386 image base to superpage
Summary:

As for x86_64, the default image base for AArch64 and i386 should be
aligned to a superpage appropriate for the architecture.

On AArch64, this is 2 MiB, on i386 it is 4 MiB.

Reviewers: emaste, grimar, javed.absar, espindola, ruiu, peter.smith, srhines, rprichard

Reviewed By: ruiu, peter.smith

Subscribers: jfb, markj, arichardson, krytarowski, kristof.beyls, llvm-commits

Differential Revision: https://reviews.llvm.org/D50297

llvm-svn: 342746
2018-09-21 16:58:13 +00:00
Petr Hosek e717ae2117 [ELF] Use the Repl point to avoid the segfault when using ICF
This addresses PR38918.

Differential Revision: https://reviews.llvm.org/D52202

llvm-svn: 342704
2018-09-21 00:55:42 +00:00
Rui Ueyama 180cd0717f Make a member function non-member. NFC.
Non-member functions are generally preferred over member functions
because it is clear that non-member functions don't depend on an
internal state of an object.

llvm-svn: 342695
2018-09-20 22:58:00 +00:00
Rui Ueyama a071669956 Rename a function. NFC.
llvm-svn: 342687
2018-09-20 21:40:38 +00:00
Rui Ueyama d19bc04869 Make variable names shorter. NFC.
llvm-svn: 342686
2018-09-20 21:29:14 +00:00
Rui Ueyama 9932091d87 Simplify. NFC.
llvm-svn: 342685
2018-09-20 21:18:56 +00:00
Sid Manning 6d0e4fce1a [ELF][HEXAGON] Set DefaultMaxPageSize to 64K
Update testcase to reflect the change.

llvm-svn: 342662
2018-09-20 16:32:19 +00:00
Sean Fertile 69e09116ba [PPC64] Handle ppc64le triple in getBitcodeMachineKind.
Enables lto and thinlto with bitcode targeting ppc64le.

Differential Revision: https://reviews.llvm.org/D52265

llvm-svn: 342604
2018-09-20 00:26:49 +00:00
Sean Fertile e0e586b997 [PPC64] Helper for offset from a function's global entry to local entry. [NFC]
The PPC64 elf V2 abi defines 2 entry points for a function. There are a few
places we need to calculate the offset from the global entry to the local entry
and how this is done is not straight forward. This patch adds a helper function
mostly for documentation purposes, explaining how the 2 entry points differ and
why we choose one over the other, as well as documenting how the offsets are
encoded into a functions st_other field.

Differential Revision: https://reviews.llvm.org/D52231

llvm-svn: 342603
2018-09-20 00:26:47 +00:00
Sean Fertile 7f3f05e0b7 [PPC64] Optimize redundant instructions in global access sequences.
The access sequence for global variables in the medium and large code models use
2 instructions to add an offset to the toc-pointer. If the offset fits whithin
16-bits then the instruction that sets the high 16 bits is redundant.

This patch adds the --toc-optimize option, (on by default) and enables rewriting
of 2 instruction global variable accesses into 1 when the offset from the
TOC-pointer to the variable (or .got entry) fits in 16 signed bits. eg

addis %r3, %r2, 0           -->     nop
addi  %r3, %r3, -0x8000     -->     addi %r3, %r2, -0x8000

This rewriting can be disabled with the --no-toc-optimize flag

Differential Revision: https://reviews.llvm.org/D49237

llvm-svn: 342602
2018-09-20 00:26:44 +00:00
Ryan Prichard 1c33d14bcd [ELF] Set Out::TlsPhdr earlier for encoding packed reloc tables
Summary:
For --pack-dyn-relocs=android, finalizeSections calls
LinkerScript::assignAddresses and
AndroidPackedRelocationSection::updateAllocSize in a loop,
where assignAddresses lays out the ELF image, then updateAllocSize
determines the size of the Android packed relocation table by encoding it.
Encoding the table requires knowing the values of relocation addends.

To get the addend of a TLS relocation, updateAllocSize can call getSymVA
on a TLS symbol before setPhdrs has initialized Out::TlsPhdr, producing an
error:

    <file> has an STT_TLS symbol but doesn't have an SHF_TLS section

Fix the problem by initializing Out::TlsPhdr immediately after the program
headers are created. The segment's p_vaddr field isn't initialized until
setPhdrs, so use FirstSec->Addr, which is what setPhdrs would use.
FirstSec will typically refer to the .tdata or .tbss output section, whose
(tentative) address was computed by assignAddresses.

Android currently avoids this problem because it uses emutls and doesn't
support ELF TLS. This problem doesn't apply to --pack-dyn-relocs=relr
because SHR_RELR only handles relative relocations without explicit addends
or info.

Fixes https://bugs.llvm.org/show_bug.cgi?id=37841.

Reviewers: ruiu, pcc, chh, javed.absar, espindola

Subscribers: emaste, arichardson, llvm-commits, srhines

Differential Revision: https://reviews.llvm.org/D51671

llvm-svn: 342432
2018-09-18 00:24:48 +00:00
Sean Fertile 72435e5701 [PPC64] Support relaxing R_PPC64_TLSGD16 in TlsGdtoLe relaxation.
A General-dynamic tls access can be written using a R_PPC64_TLSGD16 relocation
if the target got entry is within 16 bits of the TOC-base. This patch adds
support for R_PPC64_TLSGD16 by relaxing it the same as a R_PPC64_GOT_TLSGD16_LO.

Differential Revision: https://reviews.llvm.org/D52055

llvm-svn: 342411
2018-09-17 20:27:02 +00:00
Sean Fertile eed3e43e54 [PPC64] Helpers for read/write an instr while relocating a half16 type. [NFC]
There are a growing number of places when we either want to read or write an
instruction when handling a half16 relocation type. On big-endian the buffer
pointer is pointing into the middle of the word we want and on little-endian it
is pointing to the start of the word. These 2 helpers are to simplify reading
and writing in these contexts.

Differential Revision: https://reviews.llvm.org/D52115

llvm-svn: 342410
2018-09-17 20:27:00 +00:00
Fangrui Song 3e0a54e9da [ELF] Use llvm::toLower instead of libc call tolower
tolower() has some overhead because current locale is considered (though in lld the default "C" locale is used which does not matter too much). llvm::toLower is more efficient as it compiles to a compare and a conditional jump, as opposed to a libc call if tolower is used.

Disregarding locale also matches gdb's behavior (gdb/minsyms.h):

    #define SYMBOL_HASH_NEXT(hash, c)			\
      ((hash) * 67 + TOLOWER ((unsigned char) (c)) - 113)

where TOLOWER (include/safe-ctype.h) is a macro that uses a lookup table under the hood which is similar to llvm::toLower.

Reviewers: ruiu, espindola

Subscribers: emaste, arichardson, llvm-commits

Differential Revision: https://reviews.llvm.org/D52128

llvm-svn: 342342
2018-09-15 23:59:13 +00:00
Rui Ueyama 01d250eed9 Style fix. NFC.
llvm-svn: 342300
2018-09-14 23:51:17 +00:00
Rui Ueyama 970573776a Rename GdbIndex.{cpp,h} -> DWARF.{cpp,h}.
These files used to contain classes and functions for .gdb_index,
but they are moved to SyntheticSections.{cpp,h}, so the name is now
irrelevant.

llvm-svn: 342299
2018-09-14 23:51:05 +00:00
Rui Ueyama e7688e6663 Revert r342297: Discard uncompressed buffer after creating .gdb_index contents.
Looks like it broke some local builds that use -gdb-index.

llvm-svn: 342298
2018-09-14 23:28:13 +00:00
Rui Ueyama 751dfbe39b Discard uncompressed buffer after creating .gdb_index contents.
Once we create .gdb_index contents, .zdebug_gnu_pub{names,types}
are useless, so there's no need to keep their uncompressed data
in memory.

I observed that for a test case in which lld creates a 3GB .gdb_index
section, the maximum resident set size reduced from 43GB to 29GB after
this patch.

Differential Revision: https://reviews.llvm.org/D52126

llvm-svn: 342297
2018-09-14 22:57:39 +00:00
Ed Maste c0b474f67a lld: add -z interpose support
-z interpose sets the DF_1_INTERPOSE flag, marking the object as an
interposer.

Via FreeBSD PR 230604, linking Valgrind with lld failed.

Differential Revision:	https://reviews.llvm.org/D52094

llvm-svn: 342239
2018-09-14 14:25:37 +00:00
Peter Smith f31f596152 [ELF] Guard --fix-cortex-a53-843419 against --just-syms
If --just-syms is used the mapping symbols from the ELF file will be
absolute symbols with no section. The code to process mapping symbols in
--fix-cortex-a53-843419 assumes that these symbols have a defining section
so a crash will result when --just-syms is used. The simple fix is to not
process the symbol when it doesn't have a section.

Fixes PR37971

Differential Revision: https://reviews.llvm.org/D52038

llvm-svn: 342146
2018-09-13 15:49:13 +00:00
Chih-Hung Hsieh 73e04847bf [ELF] Revert "Also demote lazy symbols."
This reverts commit https://reviews.llvm.org/rL330869
for a regression to link Android dex2oatds.

Differential Revision: https://reviews.llvm.org/D51892

llvm-svn: 342007
2018-09-11 23:00:36 +00:00
Rui Ueyama 98e4a5ca11 Simplify.
Instead of Map<StringRef, bool>, we can simply use Set<StringRef>.

llvm-svn: 341948
2018-09-11 14:37:27 +00:00
Rui Ueyama 10454c4fd5 Style fix.
llvm-svn: 341937
2018-09-11 13:41:58 +00:00
Petr Hosek c6a233a68a [ELF] Don't emit .relr.dyn section if there are no relocs
This resolves PR38875.

Differential Revision: https://reviews.llvm.org/D51834

llvm-svn: 341870
2018-09-10 21:54:56 +00:00
Fangrui Song 1fe3e8b26f [ELF] Check if LinkSec is nullptr when initializing SHF_LINK_ORDER sections
Summary: This protects lld from a null pointer dereference when a faulty input file has such invalid sh_link fields.

Reviewers: ruiu, espindola

Reviewed By: ruiu

Subscribers: emaste, arichardson, llvm-commits

Differential Revision: https://reviews.llvm.org/D51743

llvm-svn: 341611
2018-09-07 00:18:07 +00:00
Sterling Augustine b55236f522 When a relocation to an undefined symbol is an R_X86_64_PC32, an input
section will not have an input file. Don't crash under those circumstances.

Neither clang nor llvm-mc generates R_X86_64_PC32 relocations due to
https://reviews.llvm.org/D43383, which makes it hard to write a test case.
However, gcc does generate such relocations. I want to get a fix in now,
but will figure out a way to actually exercise this code path as soon
as I can.

llvm-svn: 341408
2018-09-04 21:06:59 +00:00
Ben Dunbobbin df6f0ad210 [LLD] Check too large offsets into merge sections earlier
This patch moves the checking for too large offsets into merge sections
earlier.

Without this change the large offset generated in the added test-case
will cause an assert (as it happens to be a value reserved as a
"tombstone" in the DenseMap implementation) when OffsetMap is queried in
getSectionPiece().

To simplify the code and avoid future mistakes I have refactored so that
there is only one function that looks up offsets in the OffsetMap.

Differential Revision: https://reviews.llvm.org/D51180

llvm-svn: 341206
2018-08-31 11:51:51 +00:00
Martin Storsjo 24f590fca6 [ELF] [ARM] Don't mix 'ip' and 'r12' as names for the same register in comments. NFC.
llvm-svn: 341179
2018-08-31 08:03:33 +00:00
Peter Collingbourne 6556e6b929 ELF: Don't examine values of linker script symbols during ICF.
These symbols are declared early with the same value, so they otherwise
appear identical to ICF.

Differential Revision: https://reviews.llvm.org/D51376

llvm-svn: 340998
2018-08-29 23:43:38 +00:00
Rui Ueyama 025bb56a86 Always add a .note.GNU-stack section if -r.
With this patch, lld creates a .note.GNU_stack and adds that to an
output file if it is creating a re-linkable object file (i.e. if -r
is given). If we don't do this, and if you use GNU linkers as a final
linker, they create an executable whose stack area is executable,
which is considered pretty bad these days.

Differential Revision: https://reviews.llvm.org/D51400

llvm-svn: 340902
2018-08-29 07:27:09 +00:00
Sean Fertile 4d354e1199 [PPC64] Fix DQ-form instruction handling and emit error for misalignment.
Relanding r340564, original commit message:

Fixes the handling of *_DS relocations used on DQ-form instructions where we
were overwriting some of the extended opcode bits. Also adds an alignment check
so that the user will receive a diagnostic error if the value we are writing
is not properly aligned.

Differential Revision: https://reviews.llvm.org/D51124

llvm-svn: 340832
2018-08-28 15:16:01 +00:00
George Rimar f0eedbce44 [LLD][ELF] - Simplify Call-Chain Clustering implementation a bit.
Looking at the current implementation and algorithm description,
it does not seem we need to keep vector with all edges for
each cluster and can just remember the best one. This is NFC change.

Differential revision: https://reviews.llvm.org/D50609

llvm-svn: 340806
2018-08-28 08:49:40 +00:00
George Rimar a46d08ebe6 [LLD][ELD] - Do not reject INFO output section type when used with a start address.
This is https://bugs.llvm.org/show_bug.cgi?id=38625

LLD accept this: 

".stack (INFO) : {", 

but not this:

".stack address_expression (INFO) :"

The patch fixes it.

Differential revision: https://reviews.llvm.org/D51027

llvm-svn: 340804
2018-08-28 08:39:21 +00:00
George Rimar 27bbe7d0b4 [LLF][ELF] - Support -z global.
-z global is a flag used on Android (see D49198).

Differential revision: https://reviews.llvm.org/D49374

llvm-svn: 340802
2018-08-28 08:24:34 +00:00
Sid Manning 569a56d6a0 [ELF][HEXAGON] Add R_HEX_11/10/9_X support
Differential Revision: https://reviews.llvm.org/D51225

llvm-svn: 340739
2018-08-27 12:55:28 +00:00
Matt Arsenault 8d6c7a63a1 Handle identifying AMDGPU bitcode files
llvm-svn: 340738
2018-08-27 12:40:00 +00:00
Rui Ueyama 41831204c7 Rename a function to follow the LLVM coding style.
llvm-svn: 340716
2018-08-27 06:18:10 +00:00
Sid Manning 2c3d4b37b6 [ELF][HEXAGON] Add R_HEX_B13_PCREL relocation support
Differential Revision: https://reviews.llvm.org/D51166

llvm-svn: 340693
2018-08-25 23:16:37 +00:00
Sid Manning 6d0415e098 [ELF][HEXAGON] Add R_HEX_B9_PCREL and R_HEX_B9_PCREL_X relocation support
Differential Revision: https://reviews.llvm.org/D51045

llvm-svn: 340692
2018-08-25 21:25:35 +00:00
Sean Fertile 1542b0aef5 Revert "[PPC64] Fix DQ-form instruction handling and emit error for misalign..."
This reverts commit 5125b44dbb5d06b715213e4bec75c7346bfcc7d3.
ppc64-dq.s and ppc64-error-missaligned-dq.s fail on several of the build-bots.
Reverting to investigate.

llvm-svn: 340568
2018-08-23 19:10:40 +00:00
Sean Fertile a6b2ab7a91 [PPC64] Fix DQ-form instruction handling and emit error for misalignment.
Fixes the handling of *_DS relocations used on DQ-form instructions where we
were overwriting some of the extended opcode bits. Also adds an alignment check
so that the user will receive a diagnostic error if the value we are writing
is not properly aligned.

Differential Revision: https://reviews.llvm.org/D51124

llvm-svn: 340564
2018-08-23 18:35:09 +00:00
Nico Weber 386bf1216e win: Omit ".exe" from lld warning and error messages.
This is a minor follow-up to https://reviews.llvm.org/D49189. On Windows, lld
used to print "lld-link.exe: error: ...". Now it just prints "lld-link: error:
...". This matches what link.exe does (it prints "LINK : ...") and makes lld's
output less dependent on the host system.

https://reviews.llvm.org/D51133

llvm-svn: 340487
2018-08-22 23:52:13 +00:00
Sid Manning 564e65a4c0 [ELF][HEXAGON] Add R_HEX_16_X relocation
This relocation has only 6-bits the remaining are in the extender.

Differential Revision: https://reviews.llvm.org/D50603

llvm-svn: 340413
2018-08-22 15:25:15 +00:00
Rui Ueyama 07b4536bb7 Change how we handle -wrap.
We have an issue with -wrap that the option doesn't work well when
renamed symbols get PLT entries. I'll explain what is the issue and
how this patch solves it.

For one -wrap option, we have three symbols: foo, wrap_foo and real_foo.
Currently, we use memcpy to overwrite wrapped symbols so that they get
the same contents. This works in most cases but doesn't when the relocation
processor sets some flags in the symbol. memcpy'ed symbols are just
aliases, so they always have to have the same contents, but the
relocation processor breaks that assumption.

r336609 is an attempt to fix the issue by memcpy'ing again after
processing relocations, so that symbols that are out of sync get the
same contents again. That works in most cases as well, but it breaks
ASan build in a mysterious way.

We could probably fix the issue by choosing symbol attributes that need
to be copied after they are updated. But it feels too complicated to me.

So, in this patch, I fixed it once and for all. With this patch, we no
longer memcpy symbols. All references to renamed symbols point to new
symbols after wrapSymbols() is done.

Differential Revision: https://reviews.llvm.org/D50569

llvm-svn: 340387
2018-08-22 07:02:26 +00:00
Fangrui Song 887ec75173 [ELF] -thinlto-object-suffix-replace=: don't error if the path does not end with old suffix
Summary:
For -thinlto-object-suffix-replace=old\;new, in
tools/gold/gold-plugin.cpp, the thinlto object filename is Path minus
optional old suffix.

    static std::string getThinLTOObjectFileName(StringRef Path, StringRef OldSuffix,
                                                StringRef NewSuffix) {
      if (OldSuffix.empty() && NewSuffix.empty())
        return Path;
      StringRef NewPath = Path;
      NewPath.consume_back(OldSuffix);
      std::string NewNewPath = NewPath;
      NewNewPath += NewSuffix;
      return NewNewPath;
    }

Currently lld will error that the path does not end with old suffix.

This patch makes lld accept such paths but only add new suffix if Path
ends with old suffix. This fixes a link error where bitcode members in
an archive are regular LTO objects without old suffix.

Acording to tejohnson, this will "enable supporting mix and match of
minimized ThinLTO bitcode files with normal ThinLTO bitcode files in a
single link (where we want to apply the suffix replacement to the
minimized files, and just ignore it for the normal ThinLTO files)."

Reviewers: ruiu, pcc, tejohnson, espindola

Reviewed By: tejohnson

Subscribers: emaste, inglorion, arichardson, eraman, steven_wu, dexonsmith, llvm-commits

Differential Revision: https://reviews.llvm.org/D51055

llvm-svn: 340364
2018-08-21 23:28:12 +00:00
Zaara Syeda 662d146c5b [PPC64] Add TLS initial exec to local exec relaxation
This patch adds the target call back relaxTlsIeToLe to support TLS relaxation
from initial exec to local exec model.

Differential Revision: https://reviews.llvm.org/D48091

llvm-svn: 340281
2018-08-21 15:13:53 +00:00
George Rimar e2684662ee [LLD][ELF] - Check the architecture of lazy objects earlier.
Our code in LazyObjFile::parse() has an ELFT switch and
adds a lazy object by its ELFT kind.
Though it might be possible to add a file using a different
architecture and make LLD to silently accept it (if the file
is empty or contains only week symbols). That itself, not a
huge issue perhaps (because the error would be reported later
if the file is fetched), but still does not look clean and correct.

It is possible to report an error earlier and clean up the
code. That is what the patch does.

Ideally, we might want to reuse isCompatible from SymbolTable.cpp,
but it is static and accepts a file as an argument, what is not
convenient. Since such a situation should be rare, I think it
should be OK to go with the way chosen in this patch.

Differential revision: https://reviews.llvm.org/D50899

llvm-svn: 340257
2018-08-21 08:13:06 +00:00
George Rimar 20f994d350 [LLD][ELF] - Fix warning.
This fixes the following warning when compiling with gcc version 8.0.1 20180319 (experimental) (GCC):

/home/umb/LLVM/llvm/tools/lld/ELF/SyntheticSections.cpp:1951:46: warning: enumeral and non-enumeral type in conditional expression [-Wextra]
     return OS->SectionIndex >= SHN_LORESERVE ? SHN_XINDEX : OS->SectionIndex;

llvm-svn: 340164
2018-08-20 10:29:21 +00:00
Peter Smith a8656c62f5 [ELF] Add support for Armv5 and Armv6 compatible Thunks
Older Arm architectures do not support the MOVT and MOVW instructions so we
must use an alternative sequence of instructions to transfer control to the
destination.

Assuming at least Armv5 this patch adds support for Thunks that load or add
to the program counter. Note that there are no Armv5 Thumb Thunks as there
is no Thumb branch instruction in Armv5 that supports Thunks. These thunks
will not work for Armv4t (arm7tdmi) as this architecture cannot change state
from using the LDR or ADD instruction.

Differential Revision: https://reviews.llvm.org/D50077

llvm-svn: 340160
2018-08-20 09:37:50 +00:00
Peter Smith d1be026ede [ELF] Add support for older Arm Architectures with smaller branch range
The Thumb BL and BLX instructions on older Arm Architectures such as v5 and
v6 have a constrained encoding J1 and J2 must equal 1, later Architectures
relaxed this restriction allowing J1 and J2 to be used to calculate a larger
immediate.

This patch adds support for the old encoding, it is used when the build
attributes for the input objects only contain older architectures.

Differential Revision: https://reviews.llvm.org/D50076

llvm-svn: 340159
2018-08-20 09:19:30 +00:00