This matches the legacy PM's EP_ModuleOptimizerEarly. Some backends use
this extension point and adding the pass somewhere else like
PipelineStartEPCallback doesn't work.
Reviewed By: ychen
Differential Revision: https://reviews.llvm.org/D91804
This:
1) Changes its signature.
2) Refines the name of local variable (`SymTabName`->`LinkedSecName`,
because SHT_GNU_verneed/SHT_GNU_verdef are linked with the string table, not with the symbol table).
3) Stops using the `unwrapOrError` inside.
Differential revision: https://reviews.llvm.org/D91964
This stops using `RelocationRef` API in the `printStackSize` method
and starts using the "regular" API that is used in almost all other places
in ELFDumper.cpp.
This is not only makes the code to be more consistent, but helps to diagnose
issues better, because the `ELFObjectFile` API, which is used
currently to implement stack sized dumping sometimes has a behavior
that just doesn't work well for broken inputs.
E.g see how it gets the `symbol_end` iterator. It will just not work
well for a case when the `sh_size` is broken.
```
template <class ELFT>
basic_symbol_iterator ELFObjectFile<ELFT>::symbol_end() const {
...
DataRefImpl Sym = toDRI(SymTab, SymTab->sh_size / sizeof(Elf_Sym));
return basic_symbol_iterator(SymbolRef(Sym, this));
}
```
Differential revision: https://reviews.llvm.org/D91624
D91867 introduced the `tryGetSectionName` helper.
But we have `getPrintableSectionName` member with the similar
behavior which we can reuse. This patch does it.
Differential revision: https://reviews.llvm.org/D91954
llvm-symbolizer used to use the DIA SDK for symbolization on
Windows; this patch switches to using native symbolization, which was
implemented recently.
Users can still make the symbolizer use DIA by adding the `-dia` flag
in the LLVM_SYMBOLIZER_OPTS environment variable.
Differential Revision: https://reviews.llvm.org/D91814
It is possible to trigger a crash/misbehavior when the st_name field of
the signature symbol goes past the end of the string table.
This patch fixes it.
Differential revision: https://reviews.llvm.org/D91943
It is possible to trigger reading past the EOF by breaking fields like
DT_PLTRELSZ, DT_RELSZ or DT_RELASZ
This patch adds a validation in `DynRegionInfo` helper class.
Differential revision: https://reviews.llvm.org/D91787
All these potential null pointer dereferences are reported by my static analyzer for null smart pointer dereferences, which has a different implementation from `alpha.cplusplus.SmartPtr`.
The checked pointers in this patch are initialized by Target::createXXX functions. When the creator function pointer is not correctly set, a null pointer will be returned, or the creator function may originally return a null pointer.
Some of them may not make sense as they may be checked before entering the function, but I fixed them all in this patch. I submit this fix because 1) similar checks are found in some other places in the LLVM codebase for the same return value of the function; and, 2) some of the pointers are dereferenced before they are checked, which may definitely trigger a null pointer dereference if the return value is nullptr.
Reviewed By: tejohnson, MaskRay, jpienaar
Differential Revision: https://reviews.llvm.org/D91410
This stack of changes introduces `llvm-profgen` utility which generates a profile data file from given perf script data files for sample-based PGO. It’s part of(not only) the CSSPGO work. Specifically to support context-sensitive with/without pseudo probe profile, it implements a series of functionalities including perf trace parsing, instruction symbolization, LBR stack/call frame stack unwinding, pseudo probe decoding, etc. Also high throughput is achieved by multiple levels of sample aggregation and compatible format with one stop is generated at the end. Please refer to: https://groups.google.com/g/llvm-dev/c/1p1rdYbL93s for the CSSPGO RFC.
This change adds the support of instruction symbolization. Given the RVA on an instruction pointer, a full calling context can be printed side-by-side with the disassembly code.
E.g.
```
Disassembly of section .text [0x0, 0x4a]:
<funcA>:
0: mov eax, edi funcA:0
2: mov ecx, dword ptr [rip] funcLeaf:2 @ funcA:1
8: lea edx, [rcx + 3] fib:2 @ funcLeaf:2 @ funcA:1
b: cmp ecx, 3 fib:2 @ funcLeaf:2 @ funcA:1
e: cmovl edx, ecx fib:2 @ funcLeaf:2 @ funcA:1
11: sub eax, edx funcLeaf:2 @ funcA:1
13: ret funcA:2
14: nop word ptr cs:[rax + rax]
1e: nop
<funcLeaf>:
20: mov eax, edi funcLeaf:1
22: mov ecx, dword ptr [rip] funcLeaf:2
28: lea edx, [rcx + 3] fib:2 @ funcLeaf:2
2b: cmp ecx, 3 fib:2 @ funcLeaf:2
2e: cmovl edx, ecx fib:2 @ funcLeaf:2
31: sub eax, edx funcLeaf:2
33: ret funcLeaf:3
34: nop word ptr cs:[rax + rax]
3e: nop
<fib>:
40: lea eax, [rdi + 3] fib:2
43: cmp edi, 3 fib:2
46: cmovl eax, edi fib:2
49: ret fib:8
```
Test Plan:
ninja check-llvm
Reviewed By: wenlei, wmi
Differential Revision: https://reviews.llvm.org/D89715
This stack of changes introduces `llvm-profgen` utility which generates a profile data file from given perf script data files for sample-based PGO. It’s part of(not only) the CSSPGO work. Specifically to support context-sensitive with/without pseudo probe profile, it implements a series of functionalities including perf trace parsing, instruction symbolization, LBR stack/call frame stack unwinding, pseudo probe decoding, etc. Also high throughput is achieved by multiple levels of sample aggregation and compatible format with one stop is generated at the end. Please refer to: https://groups.google.com/g/llvm-dev/c/1p1rdYbL93s for the CSSPGO RFC.
This change enables disassembling the text sections to build various address maps that are potentially used by the virtual unwinder. A switch `--show-disassembly` is being added to print the disassembly code.
Like the llvm-objdump tool, this change leverages existing LLVM components to parse and disassemble ELF binary files. So far X86 is supported.
Test Plan:
ninja check-llvm
Reviewed By: wmi, wenlei
Differential Revision: https://reviews.llvm.org/D89712
This stack of changes introduces `llvm-profgen` utility which generates a profile data file from given perf script data files for sample-based PGO. It’s part of(not only) the CSSPGO work. Specifically to support context-sensitive with/without pseudo probe profile, it implements a series of functionalities including perf trace parsing, instruction symbolization, LBR stack/call frame stack unwinding, pseudo probe decoding, etc. Also high throughput is achieved by multiple levels of sample aggregation and compatible format with one stop is generated at the end. Please refer to: https://groups.google.com/g/llvm-dev/c/1p1rdYbL93s for the CSSPGO RFC.
As a starter, this change sets up an entry point by introducing PerfReader to load profiled binaries and perf traces(including perf events and perf samples). For the event, here it parses the mmap2 events from perf script to build the loader snaps, which is used to retrieve the image load address in the subsequent perf tracing parsing.
As described in llvm-profgen.rst, the tool being built aims to support multiple input perf data (preprocessed by perf script) as well as multiple input binary images. It should also support dynamic reload/unload shared objects by leveraging the loader snaps being built by this change
Reviewed By: wenlei, wmi
Differential Revision: https://reviews.llvm.org/D89707
Our code that dumps groups has 3 noticeable issues:
1) It uses `unwrapOrError` in many places.
2) It doesn't allow reporting unique warnings, because the `getGroups` helper is not
a member of `DumpStyle<ELFT>`.
3) It might just crash. See the comment for `StrTableOrErr->data() + Sym.st_name` line.
In this patch I am starting addressing these points.
For start I've converted one of `unwrapOrError` calls to a unique warning.
Differential revision: https://reviews.llvm.org/D91798
Our `printStackSize` implementation currently uses
API like `RelocationRef`, `object::symbol_iterator`.
It is not ideal as it doesn't allow
to handle possible error conditions properly.
Some time ago I started rewriting it and this NFC patch is
a one more step toward to it. Here I am introducing the
`forEachRelocationDo` helper. With it it is possible to iterate
over all kinds of relocations, what is helpful for improving
the code in `printStackSize` and around.
Differential revision: https://reviews.llvm.org/D91530
This allows to reuse the RelocationResolver from the code
that doesn't want to deal with `RelocationRef` class.
I am going to use it in llvm-readobj. See the description
of D91530 for more details.
Differential revision: https://reviews.llvm.org/D91533
In some places the parser guards against dereferencing `End`, while in
others it relies on the presence of a trailing `'\0'` to elide checks.
Add the remaining guards needed to ensure the parser never attempts to
dereference `End`, making it safe to not require a null-terminated input
buffer.
Update the parser fuzzer harness so that it tests with buffers that are
guaranteed to be non-null-terminated, null-terminated, and 1-terminated,
additionally ensuring the result of the parse is the same in each case.
Some of the regression tests were written by inspection, and some are
cases caught by the fuzzer which required additional fixes in the
parser.
Differential Revision: https://reviews.llvm.org/D84050
This is essentially a clone of the existing fuzzer added in D50839, but
for the whole parser Streamer, and currently only testing for sanitizer
violations.
Differential Revision: https://reviews.llvm.org/D91573
This patch adds support for creating Guard Address-Taken IAT Entry Tables (.giats$y sections) in object files, matching the behavior of MSVC. These contain lists of address-taken imported functions, which are used by the linker to create the final GIATS table.
Additionally, if any DLLs are delay-loaded, the linker must look through the .giats tables and add the respective load thunks of address-taken imports to the GFIDS table, as these are also valid call targets.
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D87544
In f9fb9da36c34d2745b74dc30e6c26f7d3f48466c we fixed spurious warnings
caused by aliases to private extern symbols. This patch generalizes that
to regular external symbols as well.
Patch by Elena Kovanova. Thanks Elena!
Problem:
LLVM already has a feature to profile the JIT-compiled code with VTune. This is
done using Intel JIT Profiling API (https://github.com/intel/ittapi). Function
information is captured by VTune as soon as the function is JIT-compiled. We
tried to use the same approach to report the function information generated by
the MCJIT engine – read parsing the debug information for in-memory ELF module
and report it using JIT API. As the results, we figured out that it did not work
properly for the following cases: inline functions, the functions located in
multiple source files, the functions having several bodies (address ranges).
Solution:
To overcome limitations described above, we have introduced new APIs as a part
of Intel ITT APIs to report the entire in-memory ELF module to be further
processed as regular ELF binaries with debug information.
This patch
1. Switches LLVM to open source version of Intel ITT/JIT APIs
(https://github.com/intel/ittapi) to keep it always up to date.
2. Adds support of profiling the code generated by MCJIT engine using Intel
VTune profiler
Another separate patch will get rid of obsolete Intel ITT APIs stuff, having
LLVM already switched to https://github.com/intel/ittapi.
Differential Revision: https://reviews.llvm.org/D86435
No longer rely on an external tool to build the llvm component layout.
Instead, leverage the existing `add_llvm_componentlibrary` cmake function and
introduce `add_llvm_component_group` to accurately describe component behavior.
These function store extra properties in the created targets. These properties
are processed once all components are defined to resolve library dependencies
and produce the header expected by llvm-config.
Differential Revision: https://reviews.llvm.org/D90848
implementation.
This patch aims to improve support for out-of-process JITing using OrcV2. It
introduces two new class templates, OrcRPCTargetProcessControlBase and
OrcRPCTPCServer, which together implement the TargetProcessControl API by
forwarding operations to an execution process via an Orc-RPC Endpoint. These
utilities are used to implement out-of-process JITing from llvm-jitlink to
a new llvm-jitlink-executor tool.
This patch also breaks the OrcJIT library into three parts:
-- OrcTargetProcess: Contains code needed by the JIT execution process.
-- OrcShared: Contains code needed by the JIT execution and compiler
processes
-- OrcJIT: Everything else.
This break-up allows JIT executor processes to link against OrcTargetProcess
and OrcShared only, without having to link in all of OrcJIT. Clients executing
JIT'd code in-process should start linking against OrcTargetProcess as well as
OrcJIT.
In the near future these changes will enable:
-- Removal of the OrcRemoteTargetClient/OrcRemoteTargetServer class templates
which provided similar functionality in OrcV1.
-- Restoration of Chapter 5 of the Building-A-JIT tutorial series, which will
serve as a simple usage example for these APIs.
-- Implementation of lazy, cross-target compilation in lli's -jit-kind=orc-lazy
mode.
Alternative to D74755. sectionWithinSegment() treats an empty section as having
a size of 1. Due to the rule, an empty .tdata will not be attributed to an
empty PT_TLS. (The empty p_align=64 PT_TLS is for Android Bionic's TCB
compatibility (ELF-TLS). See https://reviews.llvm.org/D62055#1507426)
Currently --only-keep-debug will not layout a segment with no section
(layoutSegmentsForOnlyKeepDebug()), thus p_offset of PT_TLS can go past the end
of the file. The strange p_offset can trigger validation errors for subsequent
tools, e.g. llvm-objcopy errors when reading back the separate debug file
(readProgramHeaders()).
This patch places such an empty segment according to its parent segment. This
special cases works for the empty PT_TLS used in Android. For a non-empty
segment, it should have at least one non-empty section and will be handled by
the normal code. Note, p_memsz PT_LOAD is rejected by both Linux and FreeBSD.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D90897
This broke both Firefox and Chromium (PR47905) due to what seems like dllimport
function not being handled correctly.
> This patch adds support for creating Guard Address-Taken IAT Entry Tables (.giats$y sections) in object files, matching the behavior of MSVC. These contain lists of address-taken imported functions, which are used by the linker to create the final GIATS table.
> Additionally, if any DLLs are delay-loaded, the linker must look through the .giats tables and add the respective load thunks of address-taken imports to the GFIDS table, as these are also valid call targets.
>
> Reviewed By: rnk
>
> Differential Revision: https://reviews.llvm.org/D87544
This reverts commit cfd8481da1adba1952e0f6ecd00440986e49a946.
This patch adds a reduction of 'special' globals that lead to further
reductions (e.g. alias or regular globals reduction) being less efficient
because there are special constraints on values referenced in those
special globals. For example, values in @llvm.used and
@llvm.compiler.used need to be named, so replacing all uses of an
alias/global with undef or a different unnamed constant results in
invalid IR.
More details:
https://llvm.org/docs/LangRef.html#intrinsic-global-variables
Reviewed By: lebedev.ri
Differential Revision: https://reviews.llvm.org/D90302
Imagine we have a YAML declaration of few sections: `foo1`, `<unnamed 2>`, `foo3`, `foo4`.
To put them into segment we can do (1*):
```
Sections:
- Section: foo1
- Section: foo4
```
or we can use (2*):
```
Sections:
- Section: foo1
- Section: foo3
- Section: foo4
```
or (3*) :
```
Sections:
- Section: foo1
## "(index 2)" here is a name that we automatically created for a unnamed section.
- Section: (index 2)
- Section: foo3
- Section: foo4
```
It looks really confusing that we don't have to list all of sections.
At first I've tried to make this rule stricter and report an error when there is a gap
(i.e. when a section is included into segment, but not listed explicitly).
This did not work perfect, because such approach conflicts with unnamed sections/fills (see (3*)).
This patch drops "Sections" key and introduces 2 keys instead: `FirstSec` and `LastSec`.
Both are optional.
Differential revision: https://reviews.llvm.org/D90458
This is recommit for D90903 with fixes for BB:
1) Used std::move<> when returning Expected<> (http://lab.llvm.org:8011/#/builders/112/builds/913)
2) Fixed the name of temporarily file in the file-headers.test (http://lab.llvm.org:8011/#/builders/36/builds/1269)
(a local old temporarily file was used before)
For creating `ELFObjectFile` instances we have the factory method
`ELFObjectFile<ELFT>::create(MemoryBufferRef Object)`.
The problem of this method is that it scans the section header to locate some sections.
When a file is truncated or has broken fields in the ELF header, this approach does
not allow us to create the `ELFObjectFile` and dump the ELF header.
This is https://bugs.llvm.org/show_bug.cgi?id=40804
This patch suggests a solution - it allows to delay scaning sections in the
`ELFObjectFile<ELFT>::create`. It now allows user code to call an object
initialization (`initContent()`) later. With that it is possible,
for example, for dumpers just to dump the file header and exit.
By default initialization is still performed as before, what helps to keep
the logic of existent callers untouched.
I've experimented with different approaches when worked on this patch.
I think this approach is better than doing initialization of sections (i.e. scan of them)
on demand, because normally users of `ELFObjectFile` API expect to work with a valid object.
In most cases when a section header table can't be read (because of an error), we don't
have to continue to work with object. So we probably don't need to implement a more complex API.
Differential revision: https://reviews.llvm.org/D90903
For creating `ELFObjectFile` instances we have the factory method
`ELFObjectFile<ELFT>::create(MemoryBufferRef Object)`.
The problem of this method is that it scans the section header to locate some sections.
When a file is truncated or has broken fields in the ELF header, this approach does
not allow us to create the `ELFObjectFile` and dump the ELF header.
This is https://bugs.llvm.org/show_bug.cgi?id=40804
This patch suggests a solution - it allows to delay scaning sections in the
`ELFObjectFile<ELFT>::create`. It now allows user code to call an object
initialization (`initContent()`) later. With that it is possible,
for example, for dumpers just to dump the file header and exit.
By default initialization is still performed as before, what helps to keep
the logic of existent callers untouched.
I've experimented with different approaches when worked on this patch.
I think this approach is better than doing initialization of sections (i.e. scan of them)
on demand, because normally users of `ELFObjectFile` API expect to work with a valid object.
In most cases when a section header table can't be read (because of an error), we don't
have to continue to work with object. So we probably don't need to implement a more complex API.
Differential revision: https://reviews.llvm.org/D90903
While generating yamls for my tests I noticed that the new debug_abbrev format (with multiple table support) was incorrectly assigning id's to the table because it was generating one per abbrev entry in the table. For instance, the first table would get id 4 when 5 abbrev entries existed in the table. By itself this is not a problem but the corresponding debug_info sections were still referencing id 0. This was introduced here: https://reviews.llvm.org/D83116.
Maybe a better fix is to actually correctly calculate the table id when emitting debug info? From a quick glance it seems to me the ID is just being calculated as the distance between the first DWARFAbbreviationDeclarationSet and the one the debug info entry points to, which means it's just its index and not the actual table id that was generated when emitting the debug_abbrev tables. With my fix I guess this is fine but on the diff that introduced this Pavel mentioned that he would like to have some sort of unique id between them but not necessarily +1 increasing, but for that to work we need to actually find the table ID, I guess by going directly to Y.DebugAbbrev but to honest I have no idea how to link the DWARFAbbreviationDeclarationSet and the Y.DebugAbbrev, so I just did this simple fix.
I also realized there's barely any tests for MachO so it might useful to invest on that if the tool is being reworked on.
Reviewed By: Higuoxing, jhenderson
Differential Revision: https://reviews.llvm.org/D87179
This diff fixes missing fields initialization (Size, VMSize).
Previously this resulted in broken binaries when multiple sections
were added in one tool's invocatation.
Test plan: make check-all
Differential revision: https://reviews.llvm.org/D90690
Some binaries can contain regular sections with zero offset and zero size.
This diff makes llvm-objcopy's handling of such sections consistent with
cctools's strip (which doesn't modify them),
previously the tool would allocate file space for them.
Test plan: make check-all
Differential revision: https://reviews.llvm.org/D90796
YAML support allows us to better test the feature in the subsequent patches. The implementation is quite similar to the .stack_sizes section.
Reviewed By: jhenderson, grimar
Differential Revision: https://reviews.llvm.org/D88717