To reland https://github.com/llvm/llvm-project/pull/124846, we need to
make symbolizer consistent with the case when line number is 0. Always
using filename and line from debug info even if the line number is 0
sounds like the reasonable path to go.
Currently, `DIContext::getLineInfoForAddress` and
`DIContext::getLineInfoForDataAddress` returns empty DILineInfo when the
debug info is missing for the given address. This is not differentiable
with the case when debug info is found for the given address but the
debug info is default value (filename:linenum is <invalid>:0).
This change wraps the return types of `DIContext::getLineInfoForAddress`
and `DIContext::getLineInfoForDataAddress` with `std::optional`.
Nothing in the affected code depends on the `ModuleName` being
null-terminated,
so take it by `StringRef` instead of `const std::string &`.
This change simplifies API consumption, since one doesn't always have a
`std::string` at the call site (might have `std::string_view` instead),
and also gives some minor performance improvements by removing
string-copies in the cache-hit path of `getOrCreateModuleInfo`.
LLVM Symbolizer attempt to symbolize addresses of optimized binaries
reports missing line numbers for some cases. It maybe due to compiler
which sometimes cannot map an instruction to line number due to
optimizations. Symbolizer should handle those cases gracefully.
Adding an option '--skip-line-zero' to symbolizer so as to report the
nearest non-zero line number.
---------
Co-authored-by: Amit Pandey <amit.pandey@amd.com>
I'm planning to remove StringRef::equals in favor of
StringRef::operator==.
- StringRef::operator==/!= outnumber StringRef::equals by a factor of
53 under llvm/ in terms of their usage.
- The elimination of StringRef::equals brings StringRef closer to
std::string_view, which has operator== but not equals.
- S == "foo" is more readable than S.equals("foo"), especially for
!Long.Expression.equals("str") vs Long.Expression != "str".
Intel Vtune/SEP has supported collecting LBR on Windows and generating
perf-script file which is same format as Linux perf script. This patch
teaches llvm-profgen to disassemble COFF binary so that we can do
Sampling based PGO on Windows.
GNU addr2line supports lookup by symbol name in addition to the existing
address lookup. llvm-symbolizer starting from
e144ae54dcb96838a6176fd9eef21028935ccd4f supports lookup by symbol name.
This change extends this lookup with possibility to specify optional
offset.
Now the address for which source information is searched for can be
specified with offset:
llvm-symbolize --obj=abc.so "SYMBOL func_22+0x12"
It decreases the gap in features of llvm-symbolizer and GNU addr2line.
This lookup now is supported for code only.
Migrated from: https://reviews.llvm.org/D139859
Pull request: https://github.com/llvm/llvm-project/pull/75067
Recent versions of GNU binutils starting from 2.39 support symbol+offset
lookup in addition to the usual numeric address lookup. This change adds
symbol lookup to llvm-symbolize and llvm-addr2line.
Now llvm-symbolize behaves closer to GNU addr2line, - if the value specified
as address in command line or input stream is not a number, it is treated as
a symbol name. For example:
llvm-symbolize --obj=abc.so func_22
llvm-symbolize --obj=abc.so "CODE func_22"
This lookup is now supported only for functions. Specification with
offset is not supported yet.
This is a recommit of 2b27948783e4bbc1132d3220d8517ef62607b558, reverted
in 39fec5457c0925bd39f67f63fe17391584e08258 because the test
llvm/test/Support/interrupts.test started failing on Windows. The test was
changed in 18f036d0105589c3175bb51a518c5d272dae61e2 and is also updated in
this commit.
Differential Revision: https://reviews.llvm.org/D149759
Recent versions of GNU binutils starting from 2.39 support symbol+offset
lookup in addition to the usual numeric address lookup. This change adds
symbol lookup to llvm-symbolize and llvm-addr2line.
Now llvm-symbolize behaves closer to GNU addr2line, - if the value specified
as address in command line or input stream is not a number, it is treated as
a symbol name. For example:
llvm-symbolize --obj=abc.so func_22
llvm-symbolize --obj=abc.so "CODE func_22"
This lookup is now supported only for functions. Specification with
offset is not supported yet.
Differential Revision: https://reviews.llvm.org/D149759
If llvm-symbolizer finds a malformed command, it echoes it to the
standard output. New versions of binutils (starting from 2.39) allow to
specify an address by a symbols. Implementation of this feature in
llvm-symbolizer makes the current reaction on invalid input
inappropriate. Almost any invalid command may be treated as a symbol
name, so the right reaction should be "symbol not found" in such case.
The exception are commands that are recognized but have incorrect
syntax, like "FILE:FILE:". The utility must produce descriptive
diagnostic for such input and route it to the stderr.
This change implements the new reaction on invalid input and is a
prerequisite for implementation of symbol lookup in llvm-symbolizer.
Differential Revision: https://reviews.llvm.org/D157210
This reverts commit a5fe6c7f5e2d1d265bd7c312ef55259fee7a68f9.
This change is causing problems with Windows build bots due to a hanging zombie llvm-symbolizer.exe process.
If llvm-symbolizer finds a malformed command, it echoes it to the
standard output. New versions of binutils (starting from 2.39) allow to
specify an address by a symbols. Implementation of this feature in
llvm-symbolizer makes the current reaction on invalid input
inappropriate. Almost any invalid command may be treated as a symbol
name, so the right reaction should be "symbol not found" in such case.
The exception are commands that are recognized but have incorrect
syntax, like "FILE:FILE:". The utility must produce descriptive
diagnostic for such input and route it to the stderr.
This change implements the new reaction on invalid input and is a
prerequisite for implementation of symbol lookup in llvm-symbolizer.
Differential Revision: https://reviews.llvm.org/D157210
"BTF" is a debug information format used by LLVM's BPF backend.
The format is much smaller in scope than DWARF, the following info is
available:
- full set of C types used in the binary file;
- types for global values;
- line number / line source code information .
BTF information is embedded in ELF as .BTF and .BTF.ext sections.
Detailed format description could be found as a part of Linux Source
tree, e.g. here: [1].
This commit modifies `llvm-objdump` utility to use line number
information provided by BTF if DWARF information is not available.
E.g., the goal is to make the following to print source code lines,
interleaved with disassembly:
$ clang --target=bpf -g test.c -o test.o
$ llvm-strip --strip-debug test.o
$ llvm-objdump -Sd test.o
test.o: file format elf64-bpf
Disassembly of section .text:
<foo>:
; void foo(void) {
r1 = 0x1
; consume(1);
call -0x1
r1 = 0x2
; consume(2);
call -0x1
; }
exit
A common production use case for BPF programs is to:
- compile separate object files using clang with `-g -c` flags;
- link these files as a final "static" binary using bpftool linker ([2]).
The bpftool linker discards most of the DWARF sections
(line information sections as well) but merges .BTF and .BTF.ext sections.
Hence, having `llvm-objdump` capable to print source code using .BTF.ext
is valuable.
The commit consists of the following modifications:
- llvm/lib/DebugInfo/BTF aka `DebugInfoBTF` component is added to host
the code needed to process BTF (with assumption that BTF support
would be added to some other tools as well, e.g. `llvm-readelf`):
- `DebugInfoBTF` provides `llvm::BTFParser` class, that loads information
from `.BTF` and `.BTF.ext` sections of a given `object::ObjectFile`
instance and allows to query this information.
Currently only line number information is loaded.
- `DebugInfoBTF` also provides `llvm::BTFContext` class, which is an
implementation of `DIContext` interface, used by `llvm-objdump` to
query information about line numbers corresponding to specific
instructions.
- Structure `DILineInfo` is modified with field `LineSource`.
`DIContext` interface uses `DILineInfo` structure to communicate
line number and source code information.
Specifically, `DILineInfo::Source` field encodes full file source code,
if available. BTF only stores source code for selected lines of the
file, not a complete source file. Moreover, stored lines are not
guaranteed to be sorted in a specific order.
To avoid reconstruction of a file source code from a set of
available lines, this commit adds `LineSource` field instead.
- `Symbolize` class is modified to use `BTFContext` instead of
`DWARFContext` when DWARF sections are not available but BTF
sections are present in the object file.
(`Symbolize` is instantiated by `llvm-objdump`).
- Integration and unit tests.
Note, that DWARF has a notion of "instruction sequence".
DWARF implementation of `DIContext::getLineInfoForAddress()` provides
inexact responses if exact address information is not available but
address falls within "instruction sequence" with some known line
information (see `DWARFDebugLine::LineTable::findRowInSeq()`).
BTF does not provide instruction sequence groupings, thus
`getLineInfoForAddress()` queries only return exact matches.
This does not seem to be a big issue in practice, but output
of the `llvm-objdump -Sd` might differ slightly when BTF
is used instead of DWARF.
[1] https://www.kernel.org/doc/html/latest/bpf/btf.html
[2] https://github.com/libbpf/bpftool
Depends on https://reviews.llvm.org/D149501
Reviewed By: MaskRay, yonghong-song, nickdesaulniers, #debug-info
Differential Revision: https://reviews.llvm.org/D149058
The symbolizer markup syntax is structured such that fields require only
previous fields for their interpretation; this was originally intended
to make adding new fields a natural extension mechanism for existing
elements. This codifies this into the spec and makes the behavior of the
llvm-symbolizer match. Extra fields are now warned about, but ignored,
rather than ignoring the whole element.
Reviewed By: mcgrathr
Differential Revision: https://reviews.llvm.org/D153821
GNU addr2line exits immediately if -e (default to a.out) specifies a file that
cannot be open or a directory. llvm-addr2line used to wait for input on if the
input file cannot be open and addresses are not specified in command line.
Replace the D147652 checkFileExists with getOrCreateModuleInfo to avoid
a separate `sys::fs::status` operation.
Reviewed By: sepavloff
Differential Revision: https://reviews.llvm.org/D153595
GNU addr2line exits immediately if it cannot open the file specified as
executable/relocatable. In contrast llvm-addr2line does not exit and, if
addresses are not specified in command line, waits for input on stdin. This
causes the test compiler-rt/test/asan/TestCases/Posix/asan-symbolize-bad-path.cc to block
forever on Gentoo (see https://reviews.llvm.org/rG27c4777f41d2ab204c1cf84ff1cccd5ba41354da#1190273).
To fix this issue the behavior llvm-addr2line now exits if
executable/relocatable file cannot be found.
It fixes https://github.com/llvm/llvm-project/issues/42099 (llvm-addr2line
does not exit when passed a non-existent file).
Differential Revision: https://reviews.llvm.org/D147652
This should be last of the "bottom-up conversions" of various demanglers
to accept std::string_view. After this, D149104 may be revisited.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D152176
D149104 converted llvm::demangle to use std::string_view. Enabling
"expensive checks" (via -DLLVM_ENABLE_EXPENSIVE_CHECKS=ON) causes
lld/test/wasm/why-extract.s to fail. The reason for this is obscure:
Reason #10007 why std::string_view is dangerous:
Consider the following pattern:
std::string_view s = ...;
const char *c = s.data();
std::strlen(c);
Is c a NUL-terminated C style string? It depends; but if it's not then
it's not safe to call std::strlen on the std::string_view::data().
std::string_view::length() should be used instead.
Fixing this fixes the one lone test that caught this.
microsoftDemangle, rustDemangle, and dlangDemangle should get this same
treatment, too. I will do that next.
Reviewed By: MaskRay, efriedma
Differential Revision: https://reviews.llvm.org/D149675
This is a recommit of 75f1f158812d, reverted in 7a443b1c493d, because
it caused compilation error in
compiler-rt/lib/sanitizer_common/symbolizer/sanitizer_symbolize.cpp.
The error was fixed by Kasimir Georgiev in de4c038c7ba2, but this
commit was reverted in de088dd3a0aa, because the initial commit was
reverted.
This commit reverts both the reverting commits, 7a443b1c493d and
de088dd3a0aa.
Original commit message is below.
If llvm-symbolize did not find module, the error looked like:
LLVMSymbolizer: error reading file: No such file or directory
This message does not follow common practice: LLVMSymbolizer is not an
utility name. Also the message did not not contain the name of missed file.
With this change the error message looks differently:
llvm-symbolizer: error: 'abc': No such file or directory
This format is closer to messages produced by other utilities and allow
proper coloring.
Differential Revision: https://reviews.llvm.org/D148032
If llvm-symbolize did not find module, the error looked like:
LLVMSymbolizer: error reading file: No such file or directory
This message does not follow common practice: LLVMSymbolizer is not an
utility name. Also the message did not not contain the name of missed file.
With this change the error message looks differently:
llvm-symbolizer: error: 'abc': No such file or directory
This format is closer to messages produced by other utilities and allow
proper coloring.
Differential Revision: https://reviews.llvm.org/D148032
This makes parsing for build IDs in the markup filter slightly more
permissive, in line with fromHex.
It also removes the distinction between missing build ID and empty build
ID; empty build IDs aren't a useful concept, since their purpose is to
uniquely identify a binary. This removes a layer of indirection wherever
build IDs are obtained.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D147485
Move the conversion of DILineInfo to JSON into a separate function, so
it can be used in other places too.
This is a prerequisite patch for implementation of symbol+offset lookup.
Differential Revision: https://reviews.llvm.org/D147112
llvm-symbolizer echoed input if it was not recognized as a valid address.
This behavior was extended to llvm-addr2line as well. GNU addr2line in
this case optputs "??:0". This difference prevents implementation of
symbol+offset lookup available in the recent versions of GNU binutils.
In that case a string that is not an address may be a symbol.
This change make reaction of llvm-addr2line on unrecognized input closer
to GNU addr2line.
On i386 Windows, after C++ names have been Itanium-mangled, the C name
mangling specific to its call convention may also be applied on top.
This change teaches symbolizer to be able to demangle this type of
mangled names.
As part of this change, `demanglePE32ExternCFunc` has also been modified
to fix unwanted stripping for vectorcall names when the demangled name
is supposed to contain a leading `_`. Notice that the vectorcall
mangling does not add either an `_` or `@` prefix. The old code always
tries to strip the prefix first, which for Itanium mangled names in
vectorcall, the leading underscore of the Itanium name gets stripped
instead and breaks the Itanium demangler.
Differential Revision: https://reviews.llvm.org/D144049
This is a fairly large changeset, but it can be broken into a few
pieces:
- `llvm/Support/*TargetParser*` are all moved from the LLVM Support
component into a new LLVM Component called "TargetParser". This
potentially enables using tablegen to maintain this information, as
is shown in https://reviews.llvm.org/D137517. This cannot currently
be done, as llvm-tblgen relies on LLVM's Support component.
- This also moves two files from Support which use and depend on
information in the TargetParser:
- `llvm/Support/Host.{h,cpp}` which contains functions for inspecting
the current Host machine for info about it, primarily to support
getting the host triple, but also for `-mcpu=native` support in e.g.
Clang. This is fairly tightly intertwined with the information in
`X86TargetParser.h`, so keeping them in the same component makes
sense.
- `llvm/ADT/Triple.h` and `llvm/Support/Triple.cpp`, which contains
the target triple parser and representation. This is very intertwined
with the Arm target parser, because the arm architecture version
appears in canonical triples on arm platforms.
- I moved the relevant unittests to their own directory.
And so, we end up with a single component that has all the information
about the following, which to me seems like a unified component:
- Triples that LLVM Knows about
- Architecture names and CPUs that LLVM knows about
- CPU detection logic for LLVM
Given this, I have also moved `RISCVISAInfo.h` into this component, as
it seems to me to be part of that same set of functionality.
If you get link errors in your components after this patch, you likely
need to add TargetParser into LLVM_LINK_COMPONENTS in CMake.
Differential Revision: https://reviews.llvm.org/D137838
