Commit Graph

4795 Commits

Author SHA1 Message Date
Todd Lipcon 747c450e6f
Fix JSON formatting when converting to trace event format
Reviewed By: dberris

Differential Revision: https://reviews.llvm.org/D96384
2021-02-10 13:00:28 +11:00
Vinicius Tinti 8b4a727281 [llvm-objdump][test] Fix --prefix tests for system-windows
Merging directories and files may produce different results on different
platforms.

Merging "./Inputs" and "source-interleave-x86_64.c" will use different
separators in POSIX and Windows.

Dedicated tests are needed for dealing with removing trailing separators
for POSIX (consider only '/') and Windows (consider '/' and '\').

Fixes D85024.
Fixes PR46368.

Reviewed By: jhenderson, MaskRay

Differential revision: https://reviews.llvm.org/D95513
2021-02-09 21:54:51 +00:00
Alex Richardson 7dc3136033 [llvm-readobj] Add support for decoding FreeBSD ELF notes
The current support only printed coredump notes, but most binaries also
contain notes. This change adds names for four FreeBSD-specific notes and
pretty-prints three of them:

NT_FREEBSD_ABI_TAG:
This note holds a 32-bit (decimal) integer containing the value of the
__FreeBSD_version macro, which is defined in crt1.o and will hold a value
such as 1300076 for a binary build on a FreeBSD 13 system.

NT_FREEBSD_ARCH_TAG:
A string containing the value of the build-time MACHINE_ARCH

NT_FREEBSD_FEATURE_CTL: A 32-bit flag that indicates to the kernel that
the binary wants certain bevahiour. Examples include setting
NT_FREEBSD_FCTL_ASLR_DISABLE which tells the kernel to disable ASLR.

After this change llvm-readobj also no longer decodes coredump-only
FreeBSD notes in non-coredump files. I've also converted the
note-freebsd.s test to use yaml2obj instead of llvm-mc.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D74393
2021-02-09 16:59:22 +00:00
Alex Richardson 135df21248 [llvm-readelf] Print raw ELF note contents if we can't parse it
Currently, if the note name is known, but the value isn't we don't print
the contents.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D74367
2021-02-09 16:59:22 +00:00
Alex Richardson d613d8eb0e [yaml2obj] Handle NT_* string values in for ELF note types
This is required for D74393.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D95953
2021-02-09 16:59:22 +00:00
Alex Richardson f4670fbfff [llvm-readobj] Print empty line between note sections in GNU mode
This matches GNU binutils.

Reviewed By: rupprecht, jhenderson, MaskRay

Differential Revision: https://reviews.llvm.org/D96010
2021-02-09 16:59:21 +00:00
Fangrui Song 3e837e1735 [llvm-objcopy][test] Stablize build-id-link-dir.test 2021-02-08 17:22:22 -08:00
Mircea Trofin f31ea86c80 Revert "[Utils] Add a switch controlling prefix warnings in UpdateTestChecks"
This reverts commit 87f8a08ce3.
2021-02-08 11:21:56 -08:00
Fangrui Song 157ac423e0 [llvm-objdump] Support PLT decoding for aarch64_be
Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D96211
2021-02-08 08:50:26 -08:00
Fangrui Song 50e4e385a4 LLVMgold.so: Fix tests after D95380 2021-02-04 21:14:36 -08:00
wlei dd9e219014 [CSSPGO][llvm-profgen] Fix bug with parsing hybrid sample trace line
when we skip the call stack starting with an external address, we should also skip the bottom LBR entry, otherwise it will cause a truncated context issue.

Reviewed By: hoy, wenlei

Differential Revision: https://reviews.llvm.org/D95480
2021-02-04 16:15:05 -08:00
wlei e10b73f646 [CSSPGO][llvm-profgen] Merge and trim profile for cold context to reduce profile size
This change allows merging and trimming cold context profile in llvm-profgen to solve profile size bloat problem. Currently when the profile's total sample is below threshold(supported by a switch), it will be considered cold and merged into a base context-less profile, which will at least keep the profile quality as good as the baseline(non-cs).

For example, two input profiles:
 [main @ foo @ bar]:60
 [main @ bar]:50
Under threshold = 100, the two profiles will be merge into one with the base context, get result:
 [bar]:110

Added two switches:
`--csprof-cold-thres=<value>`: Specified the total samples threshold for a context profile to be considered cold, with 100 being the default. Any cold context profiles will be merged into context-less base profile by default.
`--csprof-keep-cold`: Force profile generation to keep cold context profiles instead of dropping them. By default, any cold context will not be written to output profile.

Results:
Though not yet evaluating it with the latest CSSPGO, our internal branch shows neutral on performance but significantly reduce the profile size. Detailed evaluation on llvm-profgen with CSSPGO will come later.

Differential Revision: https://reviews.llvm.org/D94111
2021-02-04 11:05:03 -08:00
Fangrui Song eecbb1c776 [llvm-objdump] --source: drop the warning when there is no debug info
Warnings have been added for three cases (PR41905): (1) missing debug info, (2)
the source file cannot be found, (3) the debug info points at a line beyond the
end of the file.

(1) is probably less useful. This was brought up once on
http://lists.llvm.org/pipermail/llvm-dev/2020-April/141264.html and two
internal users mentioned it to me that it was annoying. (I personally
find the warning confusing, too.)

Users specify --source to get additional information if sources happen to be
available.  If sources are not available, it should be obvious as the output
will have no interleaved source lines. The warning can be especially annoying
when using llvm-objdump -S on a bunch of files.

This patch drops the warning when there is no debug info.
(If LLVMSymbolizer::symbolizeCode returns an `Error`, there will still be
an error. There is currently no test for an `Error` return value.
The only code path is probably a broken symbol table, but we probably already emit a warning
in that case)

`source-interleave-prefix.test` has an inappropriate "malformed" test - the test simply has no
.debug_* because new llc does not produce debug info when the filename is empty (invalid).
I have tried tampering the header of .debug_info/.debug_line but llvm-symbolizer does not warn.
This patch does not intend to add the missing test coverage.

Differential Revision: https://reviews.llvm.org/D88715
2021-02-04 09:07:44 -08:00
wlei ac14bb14e7 [CSSPGO][llvm-profgen] Compress recursive cycles in calling context
This change compresses the context string by removing cycles due to recursive function for CS profile generation. Removing recursion cycles is a way to normalize the calling context which will be better for the sample aggregation and also make the context promoting deterministic.
Specifically for implementation, we recognize adjacent repeated frames as cycles and deduplicated them through multiple round of iteration.
For example:
Considering a input context string stack:
[“a”, “a”, “b”, “c”, “a”, “b”, “c”, “b”, “c”, “d”]
For first iteration,, it removed all adjacent repeated frames of size 1:
[“a”, “b”, “c”, “a”, “b”, “c”, “b”, “c”, “d”]
For second iteration, it removed all adjacent repeated frames of size 2:
[“a”, “b”, “c”, “a”, “b”, “c”, “d”]
So in the end, we get compressed output:
[“a”, “b”, “c”, “d”]

Compression will be called in two place: one for sample's context key right after unwinding, one is for the eventual context string id in the ProfileGenerator.
Added a switch `compress-recursion` to control the size of duplicated frames, default -1 means no size limit.
Added unit tests and regression test for this.

Differential Revision: https://reviews.llvm.org/D93556
2021-02-03 22:16:07 -08:00
wlei 6bccdcdb35 Revert "[CSSPGO][llvm-profgen] Compress recursive cycles in calling context"
This reverts commit 0609f257dc.
2021-02-03 22:16:05 -08:00
wlei 0609f257dc [CSSPGO][llvm-profgen] Compress recursive cycles in calling context
This change compresses the context string by removing cycles due to recursive function for CS profile generation. Removing recursion cycles is a way to normalize the calling context which will be better for the sample aggregation and also make the context promoting deterministic.
Specifically for implementation, we recognize adjacent repeated frames as cycles and deduplicated them through multiple round of iteration.
For example:
Considering a input context string stack:
[“a”, “a”, “b”, “c”, “a”, “b”, “c”, “b”, “c”, “d”]
For first iteration,, it removed all adjacent repeated frames of size 1:
[“a”, “b”, “c”, “a”, “b”, “c”, “b”, “c”, “d”]
For second iteration, it removed all adjacent repeated frames of size 2:
[“a”, “b”, “c”, “a”, “b”, “c”, “d”]
So in the end, we get compressed output:
[“a”, “b”, “c”, “d”]

Compression will be called in two place: one for sample's context key right after unwinding, one is for the eventual context string id in the ProfileGenerator.
Added a switch `compress-recursion` to control the size of duplicated frames, default -1 means no size limit.
Added unit tests and regression test for this.

Differential Revision: https://reviews.llvm.org/D93556
2021-02-03 18:50:14 -08:00
wlei c82b24f475 [CSSPGO][llvm-profgen] Pseudo probe based CS profile generation
This change implements profile generation infra for pseudo probe in llvm-profgen. During virtual unwinding, the raw profile is extracted into range counter and branch counter and aggregated to sample counter map indexed by the call stack context. This change introduces the last step and produces the eventual profile. Specifically, the body of function sample is recorded by going through each probe among the range and callsite target sample is recorded by extracting the callsite probe from branch's source.

Please refer https://groups.google.com/g/llvm-dev/c/1p1rdYbL93s and https://reviews.llvm.org/D89707 for more context about CSSPGO and llvm-profgen.

**Implementation**

- Extended `PseudoProbeProfileGenerator` for pseudo probe based profile generation.
- `populateBodySamplesWithProbes` reading range counter is responsible for recording function body samples and inferring caller's body samples.
- `populateBoundarySamplesWithProbes` reading branch counter is responsible for recording call site target samples.
- Each sample is recorded with its calling context(named `ContextId`). Remind that the probe based context key doesn't include the leaf frame probe info, so the `ContextId` string is created from two part: one from the probe stack strings' concatenation and other one from the leaf frame probe.
- Added regression test

Test Plan:

ninja & ninja check-llvm

Differential Revision: https://reviews.llvm.org/D92998
2021-02-03 16:21:53 -08:00
Florian Hahn 7db390cc77
Revert "[LTO] Use lto::backend for code generation."
This reverts commit 6a59f05606, because
it is causing failures on green dragon.
2021-02-03 22:49:30 +00:00
Abhina Sreeskantharajan e59d336e75 [test] Use host platform specific error message substitution in lit tests - continued
On z/OS, other error messages are not matched correctly in lit tests.

```
EDC5121I Invalid argument.
EDC5111I Permission denied.
```

This patch adds a lit substitution to fix it.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D95808
2021-02-03 09:53:22 -05:00
Fangrui Song 1560a00032 [yaml2obj/obj2yaml/llvm-readobj] Support SHF_GNU_RETAIN
In binutils, the flag is defined for ELFOSABI_GNU and ELFOSABI_FREEBSD.
It can be used to mark a section as a GC root.

In practice, the flag has generic semantics and can be applied to many
EI_OSABI values, so we consider it generic.

Differential Revision: https://reviews.llvm.org/D95728
2021-02-02 09:19:53 -08:00
Andrew Ng 94fedd2661 [X86] Fix disassembly of x86-64 GDTLS code sequence
For x86-64 the REX.w prefix takes precedence over any other size
override (i.e. 0x66). Therefore, for x86-64 when REX.w is present set
'hasOpSize' to false to ensure that any size override is ignored.

Fixes PR48901.

Differential Revision: https://reviews.llvm.org/D95682
2021-02-02 11:35:00 +00:00
Mircea Trofin 87f8a08ce3 [Utils] Add a switch controlling prefix warnings in UpdateTestChecks
The switch controls both unused prefix warnings, and warnings about
functions which differ under different runs for a prefix, and, thus, end
up not having asserts for that prefix.

(If the latter case spans to all functions, then the former case kicks
in)

The switch is on by default, and can be disabled.

Differential Revision: https://reviews.llvm.org/D95829
2021-02-01 18:04:18 -08:00
Rahman Lavaee f1ff6d210a [obj2yaml, yaml2obj] Use Hex64 for BBAddressMap fields.
This patch let the yaml encoding use Hex64 values for NumBlocks, BB AddressOffset, BB Size, and BB Metadata.
Additionally, it changes the decoded values in elf2yaml to uint64_t to match DataExtractor::getULEB128 return type.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D95767
2021-02-01 15:37:30 -08:00
Patrick Oppenlander 93345e825a [llvm-objcopy] -O binary: consider SHT_NOBITS sections to be empty
This is consistent with BFD objcopy.

Previously llvm objcopy would allocate space for SHT_NOBITS sections
often resulting in enormous binary files.

New test case (binary-paddr.test %t6).

Reviewed By: jhenderson, MaskRay

Differential Revision: https://reviews.llvm.org/D95569
2021-02-01 15:01:25 -08:00
Haowei Wu 771b359654 [elfabi] Fix tests which failed on different timezones
This patch fixes elfabi tests on machines using a GMT+X timezone
settings.

Differential Revision: https://reviews.llvm.org/D95641
2021-02-01 10:58:55 -08:00
Teresa Johnson 7f2e0879b5 [LTO] Move part of gold devirt test to v1.16 directory
Part of the gold test added in 1487747e99
relies on more recent fixes to gold that fix the plugin behavior with
--export-dynamic-symbol and --dynamic-list. Extract those parts of the
new test into a v1.16 test.
2021-02-01 09:53:11 -08:00
Alexey Lapshin fb244ffb9f [dsymutil][DWARFLinker][NFC] make AddressManager not depending on the order of checks for relocations.
Current dsymutil implementation of hasLiveMemoryLocation()/hasLiveAddressRange()
and applyValidRelocs() assume that calls should be done in certain order
(from first Dies to last). Multi-thread implementation might call these methods
in other order(it might process compilation units in order other than they are physically
located), so we remove restriction that searching for relocations should be done
in ascending order. This change does not introduce noticable performance degradation.
The testing results for clang binary:

golden-dsymutil/dsymutil  23787992
clang MD5: 5efa8fd9355ebf81b65f24db5375caa2
elapsed time=91sec

build-Release/bin/dsymutil 23855616
clang MD5: 5efa8fd9355ebf81b65f24db5375caa2
elapsed time=91sec

Differential Revision: https://reviews.llvm.org/D93106
2021-01-31 16:34:10 +03:00
Georgii Rymar d221406875 [llvm-symbolizer] - Fix the crash in GNU output style with --no-inlines and missing input file.
Fixes https://bugs.llvm.org/show_bug.cgi?id=48882.

If the input file does not exist (or has a reading error), the
following code will crash if there are two or more input addresses.

```
auto ResOrErr = Symbolizer.symbolizeInlinedCode(
  ModuleName, {Offset, object::SectionedAddress::UndefSection});
Printer << (error(ResOrErr) ? DILineInfo() : ResOrErr.get().getFrame(0));
```

For the first address, `symbolizeInlinedCode` returns an error.
For the second address, `symbolizeInlinedCode` returns an empty result
(not an error) and `.getFrame(0)` will crash.

Differential revision: https://reviews.llvm.org/D95609
2021-01-30 18:36:38 +03:00
Florian Hahn 6a59f05606 [LTO] Use lto::backend for code generation.
This patch updates LTOCodeGenerator to use the utilities provided by
LTOBackend to run middle-end optimizations and backend code generation.

This is a first step towards unifying the code used by libLTO's C API
and the newer, C++ interface (see PR41541).

The immediate motivation is to allow using the new pass manager when
doing LTO using libLTO's C API, which is used on Darwin, among others.

With the changes, there are no codegen/stats differences when building
MultiSource/SPEC2000/SPEC2006 on Darwin X86 with LTO, compared
to without the patch.

Reviewed By: steven_wu

Differential Revision: https://reviews.llvm.org/D94487
2021-01-30 10:09:55 +00:00
Greg McGary 61a5502a93 [llvm-objdump-macho] print per-second-level-page encodings for option --unwind-info
Compact unwind entries have 8 bits for the encoding-table offset:
* offsets 0..126 reference the global commmon-encodings table, while
* offsets 127..255 reference a per-second-level-page table.
This diff teaches `llvm-objdump` to print this per-page encodings table.

Differential Revision: https://reviews.llvm.org/D93265
2021-01-29 21:59:07 -07:00
Abhina Sreeskantharajan 42a21778f6 [test] Use host platform specific error message substitution in lit tests
On z/OS, the following error message is not matched correctly in lit tests.

```
EDC5129I No such file or directory.
```

This patch uses a lit config substitution to check for platform specific error messages.

Reviewed By: muiez, jhenderson

Differential Revision: https://reviews.llvm.org/D95246
2021-01-29 07:16:30 -05:00
Georgii Rymar a5154ab9b0 [llvm-readobj/elf] - Report "bitcode files are not supported" warning for bitcode files.
Fixes https://bugs.llvm.org/show_bug.cgi?id=43543

Currently we report "The file was not recognized as a valid object file" for BC files.
Also, we terminate dumping.

Instead we could report a better warning and try to continue dumping other files.
This is what this patch implements.

Differential revision: https://reviews.llvm.org/D95605
2021-01-29 12:04:41 +03:00
Greg Clayton f8122d3532 Add the ability to extract the unwind rows from DWARF Call Frame Information.
This patch adds the ability to evaluate the state machine for CIE and FDE unwind objects and produce a UnwindTable with all UnwindRow objects needed to unwind registers. It will also dump the UnwindTable for each CIE and FDE when dumping DWARF .debug_frame or .eh_frame sections in llvm-dwarfdump or llvm-objdump. This allows users to see what the unwind rows actually look like for a given CIE or FDE instead of just seeing a list of opcodes.

This patch adds new classes: UnwindLocation, RegisterLocations, UnwindRow, and UnwindTable.

UnwindLocation is a class that describes how to unwind a register or Call Frame Address (CFA).

RegisterLocations is a class that tracks registers and their UnwindLocations. It gets populated when parsing the DWARF call frame instruction opcodes for a unwind row. The registers are mapped from their register numbers to the UnwindLocation in a map.

UnwindRow contains the result of evaluating a row of DWARF call frame instructions for the CIE, or a row from a FDE. The CIE can produce a set of initial instructions that each FDE that points to that CIE will use as the seed for the state machine when parsing FDE opcodes. A UnwindRow for a CIE will not have a valid address, whille a UnwindRow for a FDE will have a valid address.

The UnwindTable is a class that contains a sorted (by address) vector of UnwindRow objects and is the result of parsing all opcodes in a CIE, or FDE. Parsing a CIE should produce a UnwindTable with a single row. Parsing a FDE will produce a UnwindTable with one or more UnwindRow objects where all UnwindRow objects have valid addresses. The rows in the UnwindTable will be sorted from lowest Address to highest after parsing the state machine, or an error will be returned if the table isn't sorted. To parse a UnwindTable clients can use the following methods:

    static Expected<UnwindTable> UnwindTable::create(const CIE *Cie);
    static Expected<UnwindTable> UnwindTable::create(const FDE *Fde);

A valid table will be returned if the DWARF call frame instruction opcodes have no encoding errors. There are a few things that can go wrong during the evaluation of the state machine and these create functions will catch and return them.

Differential Revision: https://reviews.llvm.org/D89845
2021-01-28 13:39:17 -08:00
Fangrui Song b3af96d07b [llvm-nm] Display defined weak STT_GNU_IFUNC symbols as 'i'
This patch makes the behavior match GNU nm.
Note: undefined STT_GNU_IFUNC symbols use 'U'.

Differential Revision: https://reviews.llvm.org/D95461
2021-01-28 09:46:05 -08:00
Rahman Lavaee 3ca502a7d6 Use DataExtractor to decode SLEB128 in android_relas.
A simple refactoring patch which let us use `DataExtractor::getSLEB128` rather than using a lambda function.

Differential Revision: https://reviews.llvm.org/D95158
2021-01-28 01:35:18 -08:00
Georgii Rymar 68195b15a3 [yaml2obj] - Allow empty SectionHeaderTable definitions.
Currently we don't allow the following definition:

```
Sections:
  - Type: SectionHeaderTable
  - Name: .foo
    Type: SHT_PROGBITS
```

We report an error: "SectionHeaderTable can't be empty. Use 'NoHeaders' key to drop the section header table".

It was implemented in this way earlier, when `SectionHeaderTable`
was a dedicated key outside of the `Sections` list. And we did not
allow to select where the table is written.

Currently it makes sense to allow it, because a user might
want to place the default section header table at an arbitrary position,
e.g. before other sections. In this case it is not convenient and error prone
to require specifying all sections:

```
Sections:
  - Type: SectionHeaderTable
    Sections:
      - Name: .foo
      - Name: .strtab
      - Name: .shstrtab
  - Name: .foo
    Type: SHT_PROGBITS
```

This patch allows empty SectionHeaderTable definitions.

Differential revision: https://reviews.llvm.org/D95341
2021-01-28 10:51:52 +03:00
Hongtao Yu 7e99bddfea [CSSPGO] Support of CS profiles in extended binary format.
This change brings up support of context-sensitive profiles in the format of extended binary. Existing sample profile reader/writer/merger code is being tweaked to reflect the fact of bracketed input contexts, like (`[...]`). The paired brackets are also needed in extbinary profiles because we don't yet have an otherwise good way to tell calling contexts apart from regular function names since the context delimiter `@` can somehow serve as a part of the C++ mangled names.

Reviewed By: wmi, wenlei

Differential Revision: https://reviews.llvm.org/D95547
2021-01-27 21:29:46 -08:00
Teresa Johnson 1487747e99 [LTO] Prevent devirtualization for symbols dynamically exported
Identify dynamically exported symbols (--export-dynamic[-symbol=],
--dynamic-list=, or definitions needed to preempt shared objects) and
prevent their LTO visibility from being upgraded.
This helps avoid use of whole program devirtualization when there may
be overrides in dynamic libraries.

Differential Revision: https://reviews.llvm.org/D91583
2021-01-27 15:54:13 -08:00
Fangrui Song 54fb3ca96e [ThinLTO] Add Visibility bits to GlobalValueSummary::GVFlags
Imported functions and variable get the visibility from the module supplying the
definition.  However, non-imported definitions do not get the visibility from
(ELF) the most constraining visibility among all modules (Mach-O) the visibility
of the prevailing definition.

This patch

* adds visibility bits to GlobalValueSummary::GVFlags
* computes the result visibility and propagates it to all definitions

Protected/hidden can imply dso_local which can enable some optimizations (this
is stronger than GVFlags::DSOLocal because the implied dso_local can be
leveraged for ELF -shared while default visibility dso_local has to be cleared
for ELF -shared).

Note: we don't have summaries for declarations, so for ELF if a declaration has
the most constraining visibility, the result visibility may not be that one.

Differential Revision: https://reviews.llvm.org/D92900
2021-01-27 10:43:51 -08:00
Fangrui Song 4d28f0a6a4 [llc] Add reportError helper and canonicalize error messages 2021-01-26 15:33:37 -08:00
Fangrui Song 79ce46e275 [llvm-elfabi] Fix test after D95140 2021-01-26 12:45:45 -08:00
Haowei Wu 15313f64be [llvm-elfabi] Support ELF file that lacks .gnu.hash section
Before this change, when reading ELF file, elfabi determines number of
entries in .dynsym by reading the .gnu.hash section. This change makes
elfabi read section headers directly first. This change allows elfabi
works on ELF files which do not have .gnu.hash sections.

Differential Revision: https://reviews.llvm.org/D93362
2021-01-26 12:31:52 -08:00
Fangrui Song 34b60d8a56 Add -fbinutils-version= to gate ELF features on the specified binutils version
There are two use cases.

Assembler
We have accrued some code gated on MCAsmInfo::useIntegratedAssembler().  Some
features are supported by latest GNU as, but we have to use
MCAsmInfo::useIntegratedAs() because the newer versions have not been widely
adopted (e.g. SHF_LINK_ORDER 'o' and 'unique' linkage in 2.35, --compress-debug-sections= in 2.26).

Linker
We want to use features supported only by LLD or very new GNU ld, or don't want
to work around older GNU ld. We currently can't represent that "we don't care
about old GNU ld".  You can find such workarounds in a few other places, e.g.
Mips/MipsAsmprinter.cpp PowerPC/PPCTOCRegDeps.cpp X86/X86MCInstrLower.cpp
AArch64 TLS workaround for R_AARCH64_TLSLD_MOVW_DTPREL_* (PR ld/18276),
R_AARCH64_TLSLE_LDST8_TPREL_LO12 (https://bugs.llvm.org/show_bug.cgi?id=36727 https://sourceware.org/bugzilla/show_bug.cgi?id=22969)

Mixed SHF_LINK_ORDER and non-SHF_LINK_ORDER components (supported by LLD in D84001;
GNU ld feature request https://sourceware.org/bugzilla/show_bug.cgi?id=16833 may take a while before available).
This feature allows to garbage collect some unused sections (e.g. fragmented .gcc_except_table).

This patch adds `-fbinutils-version=` to clang and `-binutils-version` to llc.
It changes one codegen place in SHF_MERGE to demonstrate its usage.
`-fbinutils-version=2.35` means the produced object file does not care about GNU
ld<2.35 compatibility. When `-fno-integrated-as` is specified, the produced
assembly can be consumed by GNU as>=2.35, but older versions may not work.

`-fbinutils-version=none` means that we can use all ELF features, regardless of
GNU as/ld support.

Both clang and llc need `parseBinutilsVersion`. Such command line parsing is
usually implemented in `llvm/lib/CodeGen/CommandFlags.cpp` (LLVMCodeGen),
however, ClangCodeGen does not depend on LLVMCodeGen. So I add
`parseBinutilsVersion` to `llvm/lib/Target/TargetMachine.cpp` (LLVMTarget).

Differential Revision: https://reviews.llvm.org/D85474
2021-01-26 12:28:23 -08:00
Georgii Rymar d5e48f1347 [yaml2obj][obj2yaml] - Improve how we set/dump the sh_entsize field.
We already set the `sh_entsize` field in a single place
for all non-implicit sections.

This patch reorders the logic slightly and with it
we finally have the only one place where the `sh_entsize` is set.

obj2yaml will not dump the `EntSize` key for `SHT_DYNSYM/SHT_SYMTAB` sections anymore,
when the value of `sh_entsize` is equal to `sizeof(Elf_Sym)`

Note that this also seems revealed an issue in llvm-objcopy:
Previously yaml2obj set the `sh_entsize` for the `.symtab` section to 0x18,
now we it sets it for `SHT_SYMTAB` sections, i.e. by type.
But the `llvm-objcopy/ELF/only-keep-debug.test` has a `.symtab` section of type `SHT_STRTAB`,
and now yaml2obj sets the `sh_entsize` to 0 for it.
I had to update the corresponding check lines for `ES`, but the behavior of
`llvm-objcopy` should be fixed instead I think.
I've added a TODO and a comment.

Differential revision: https://reviews.llvm.org/D95364
2021-01-26 13:33:02 +03:00
Ben Shi 2d7aa149a4 [update_llc_test_checks] Support AVR
Reviewed By: arichardson

Differential Revision: https://reviews.llvm.org/D95240
2021-01-26 17:50:56 +08:00
Georgii Rymar db92d47cf7 [llvm-nm][ELF] - Use @@ prefix when printing default versions.
llvm-readelf prints default versions with `@@` prefix.
This patch does the same for llvm-nm.

Differential revision: https://reviews.llvm.org/D94912
2021-01-26 12:16:38 +03:00
Georgii Rymar e98d5c3192 [libObject,llvm-readelf/obj] - Don't use @@ when printing versions of undefined symbols.
A default version (@@) is only available for defined symbols.

Currently we use "@@" for undefined symbols too.
This patch fixes the issue and improves our test case.

Differential revision: https://reviews.llvm.org/D95219
2021-01-26 12:05:59 +03:00
Sam Clegg 84c6f32584 [Object][WebAssembly] Update format of error messages
Error message should start with lowercase in accordance with
https://llvm.org/docs/CodingStandards.html#error-and-warning-messages

Differential Revision: https://reviews.llvm.org/D95239
2021-01-25 21:12:53 -08:00
Abhina Sreeskantharajan 978444d531 Revert "[SystemZ][z/OS] Fix No such file or directory expression error"
This reverts commit 06f8a49693.
2021-01-25 08:29:38 -05:00
Abhina Sreeskantharajan 84851a274e Revert "[SystemZ][z/OS] Fix No such file or directory expression error matching in lit tests - continued"
This reverts commit 520b5ecf85.
2021-01-25 08:29:38 -05:00