233 Commits

Author SHA1 Message Date
Stefan Gränitz
3b387d1070 Lift EHPersonalities from Analysis to IR (NFC)
Computing EH-related information was only relevant for analysis passes so far. Lifting it to IR will allow the IR Verifier to calculate EH funclet coloring and validate funclet operand bundles in a follow-up step.

Reviewed By: rnk, compnerd

Differential Revision: https://reviews.llvm.org/D138122
2023-01-27 18:05:13 +01:00
Jonas Paulsson
dc3875e468 Add parameter extension attributes in various instrumentation passes.
For the targets that have in their ABI the requirement that arguments and
return values are extended to the full register bitwidth, it is important
that calls when built also take care of this detail.

The OMPIRBuilder, AddressSanitizer, GCOVProfiling, MemorySanitizer and
ThreadSanitizer passes are with this patch hopefully now doing this properly.

Reviewed By: Eli Friedman, Ulrich Weigand, Johannes Doerfert

Differential Revision: https://reviews.llvm.org/D133949
2023-01-18 18:29:12 -06:00
Sami Tolvanen
a78cfd5909 [GCOV] Set !kcfi_type metadata for indirectly called functions
With CONFIG_GCOV_KERNEL, the Linux kernel indirectly calls the
__llvm_gcov_* functions generated by LLVM. With -fsanitize=kcfi,
these calls are made from instrumented code and fail indirect
call checks as they don't have !kcfi_type metadata. Similarly
to D138945, set type metadata for these functions to allow GCOV
and KCFI to be both enabled.

Link: https://github.com/ClangBuiltLinux/linux/issues/1778

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D141444
2023-01-11 22:53:22 +00:00
Kazu Hirata
b18ff9c461 [Transform] Use range-based for loops (NFC) 2022-08-27 23:54:32 -07:00
Kazu Hirata
e20d210eef [llvm] Qualify auto (NFC)
Identified with readability-qualified-auto.
2022-08-07 23:55:27 -07:00
Ellis Hoag
12e78ff881 [InstrProf] Add the skipprofile attribute
As discussed in [0], this diff adds the `skipprofile` attribute to
prevent the function from being profiled while allowing profiled
functions to be inlined into it. The `noprofile` attribute remains
unchanged.

The `noprofile` attribute is used for functions where it is
dangerous to add instrumentation to while the `skipprofile` attribute is
used to reduce code size or performance overhead.

[0] https://discourse.llvm.org/t/why-does-the-noprofile-attribute-restrict-inlining/64108

Reviewed By: phosek

Differential Revision: https://reviews.llvm.org/D130807
2022-08-04 08:45:27 -07:00
Nuno Lopes
80b3dcc045 [Support] Make report_fatal_error respect its GenCrashDiag argument so it doesn't generate a backtrace
There are a few places where we use report_fatal_error when the input is broken.
Currently, this function always crashes LLVM with an abort signal, which
then triggers the backtrace printing code.
I think this is excessive, as wrong input shouldn't give a link to
LLVM's github issue URL and tell users to file a bug report.
We shouldn't print a stack trace either.

This patch changes report_fatal_error so it uses exit() rather than
abort() when its argument GenCrashDiag=false.

Reviewed by: nikic, MaskRay, RKSimon

Differential Revision: https://reviews.llvm.org/D126550
2022-05-30 19:19:23 +01:00
serge-sans-paille
7030654296 [iwyu] Handle regressions in libLLVM header include
Running iwyu-diff on LLVM codebase since fa5a4e1b95c8f37796 detected a few
regressions, fixing them.

Differential Revision: https://reviews.llvm.org/D124847
2022-05-04 08:32:38 +02:00
Fangrui Song
409eb5dc3e [LegacyPM] Remove GCOVProfilerLegacyPass
Using the legacy PM for the optimization pipeline was deprecated in 13.0.0.
Following recent changes to remove non-core features of the legacy
PM/optimization pipeline, remove GCOVProfilerLegacyPass.

I have checked many LLVM users and only llvm-hs[1] uses the legacy gcov pass.

[1]: https://github.com/llvm-hs/llvm-hs/issues/392

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D123829
2022-04-21 10:59:30 -07:00
serge-sans-paille
ed98c1b376 Cleanup includes: DebugInfo & CodeGen
Discourse thread: https://discourse.llvm.org/t/include-what-you-use-include-cleanup
Differential Revision: https://reviews.llvm.org/D121332
2022-03-12 17:26:40 +01:00
Matthias Braun
6a383369f9 PGOInstrumentation, GCOVProfiling: Split indirectbr critical edges regardless of PHIs
The `SplitIndirectBrCriticalEdges` function was originally designed for
`CodeGenPrepare` and skipped splitting of edges when the destination
block didn't contain any `PHI` instructions. This only makes sense when
reducing COPYs like `CodeGenPrepare`. In the case of
`PGOInstrumentation` or `GCOVProfiling` it would result in missed
counters and wrong result in functions with computed goto.

Differential Revision: https://reviews.llvm.org/D120096
2022-02-23 16:27:37 -08:00
Simon Pilgrim
21661607ca [llvm] Replace report_fatal_error(std::string) uses with report_fatal_error(Twine)
As described on D111049, we're trying to remove the <string> dependency from error handling and replace uses of report_fatal_error(const std::string&) with the Twine() variant which can be forward declared.
2021-10-06 12:04:30 +01:00
Arthur Eubanks
a1b21ed3fb [GCov] Emit memset instead of stores in __llvm_gcov_reset
For a very large module, __llvm_gcov_reset can become very large.
__llvm_gcov_reset previously emitted stores to a bunch of globals in one
huge basic block. MemCpyOpt would turn many of these stores into
memsets, and updating MemorySSA would be extremely slow.

Verified that this makes the compile time of certain files go down
drastically (20min -> 5min).

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D107538
2021-08-05 22:40:15 -07:00
Nick Desaulniers
bef2992861 [GCOVProfiling] don't profile Fn's w/ noprofile attribute
Similar to D104475, the Linux kernel would like to avoid compiler
generated code in certain functions. The no_profile function
attribute can be used in C to generate the the noprofile fn attr in IR.
Respect that from GCOVProfiling.

Link: https://lore.kernel.org/lkml/CAKwvOdmPTi93n2L0_yQkrzLdmpxzrOR7zggSzonyaw2PGshApw@mail.gmail.com/

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D104257
2021-06-18 13:58:34 -07:00
Fangrui Song
614de225c9 [gcov] Set nounwind and respect module flags metadata "frame-pointer" & "uwtable" for synthesized functions
This applies the D100251 mechanism to the gcov instrumentation pass.

With this patch, `-fno-omit-frame-pointer` in
`clang -fprofile-arcs -O1 -fno-omit-frame-pointer` will be respected for synthesized
`__llvm_gcov_writeout,__llvm_gcov_reset,__llvm_gcov_init` functions: the frame pointer
will be kept (note: on many targets -O1 eliminates the frame pointer by default).

`clang -fno-exceptions -fno-asynchronous-unwind-tables -g -fprofile-arcs` will
produce .debug_frame instead of .eh_frame.

Fix: https://github.com/ClangBuiltLinux/linux/issues/955

Reviewed By: nickdesaulniers

Differential Revision: https://reviews.llvm.org/D101129
2021-04-26 13:30:21 -07:00
James Y Knight
24539f1ef2 Add Alignment argument to IRBuilder CreateAtomicRMW and CreateAtomicCmpXchg.
And then push those change throughout LLVM.

Keep the old signature in Clang's CGBuilder for now -- that will be
updated in a follow-on patch (D97224).

The MLIR LLVM-IR dialect is not updated to support the new alignment
attribute, but preserves its existing behavior.

Differential Revision: https://reviews.llvm.org/D97223
2021-02-25 18:29:42 -05:00
Kazu Hirata
d12a0f4fc0 [GCOV] Drop unnecessary const from return types (NFC)
Identified with readability-const-return-type.
2021-02-10 20:01:18 -08:00
Roman Lebedev
59127de243
[NFC][GCOV] Fix build: there's llvm::stable_partition() wrapper 2020-10-05 22:52:32 +03:00
Fangrui Song
e338f8fe69 [gcov] Fix non-determinism (DenseMap iteration order) of checksum computation
... by using MapVector. The issue was caused by 63182c2ac0b643a60d397274e8a31166fc7243fa.

Also use stable_partition instead of partition to get stable results
across different STL implementations.
2020-10-05 12:39:36 -07:00
David Blaikie
6e06f1cd08 GCOVProfiling: Avoid use-after-move
Turns out this was use-after-move of function_ref, which is trivially
copyable and movable, so the move did nothing and use after move was
safe.

But since this function_ref is being copied into a std::function, change
the function_ref to be std::function to avoid extra layers of type
erasure indirection - and then it's a real use after move, and fix that
by referring to the moved-to member variable rather than the moved-from
parameter.
2020-09-13 12:54:36 -07:00
Fangrui Song
5f4e9bf641 [gcov] Fix memory leak due to BranchProbabilityInfoWrapperPass
This is weird.
2020-09-13 00:44:32 -07:00
Fangrui Song
63182c2ac0 [gcov] Add spanning tree optimization
gcov is an "Edge Profiling with Edge Counters" application according to
Optimally Profiling and Tracing Programs (1994).

The minimum number of counters necessary is |E|-(|V|-1). The unmeasured edges
form a spanning tree. Both GCC --coverage and clang -fprofile-generate leverage
this optimization. This patch implements the optimization for clang --coverage.
The produced .gcda files are much smaller now.
2020-09-13 00:07:31 -07:00
Fangrui Song
f086e85eea [gcov] Assign names to some types and loaded values used in @__llvm_internal*
This makes the generated IR much more readable.
2020-09-12 22:42:37 -07:00
Fangrui Song
d6fadc49e3 [gcov] Process .gcda immediately after the accompanying .gcno instead of doing all .gcda after all .gcno
i.e. change the work flow from

* .gcno for function A
* .gcno for function B
* .gcno for function C
* .gcda for function A
* .gcda for function B
* .gcda for function C

to

* .gcno for function A
* .gcda for function A
* .gcno for function B
* .gcda for function B
* .gcno for function C
* .gcda for function C

Currently there is duplicate logic in .gcno & .gcda processing: how functions
are filtered, which edges are instrumented, etc. This refactor enables simplification.

Since we always process .gcno, in -fprofile-arcs -fno-test-coverage mode,
__llvm_internal_gcov_emit_function_args.0 will have non-zero checksums.
2020-09-12 13:53:03 -07:00
Fangrui Song
7d3825ed95 Revert "[gcov] emitProfileArcs: iterate over GCOVFunction's instead of Function's to avoid duplicated filtering"
This reverts commit 412c9c0bf2a8ccbda2d925575891a51ef5df846e.
2020-09-12 12:34:43 -07:00
Fangrui Song
412c9c0bf2 [gcov] emitProfileArcs: iterate over GCOVFunction's instead of Function's to avoid duplicated filtering 2020-09-12 12:21:32 -07:00
Fangrui Song
c55c14837e [gcov] Clean up by getting llvm.dbg.cu earlier 2020-09-12 12:21:32 -07:00
Fangrui Song
ad61e346d3 [gcov] Give the __llvm_gcov_ctr load instruction a name for more readable output 2020-09-09 12:34:43 -07:00
Fangrui Song
dbac20bb6b [gcov] Don't split entry block; add a synthetic entry block instead
The entry block is split at the first instruction where `shouldKeepInEntry`
returns false. The created basic block has a br jumping to the original entry
block. The new basic block causes the function label line and the other entry
block lines to be covered by different basic blocks, which can affect line
counts with special control flows (fork/exec in the entry block requires
heuristics in llvm-cov gcov to get consistent line counts).

  int main() { // BB0
    return 0;  // BB2 (due to entry block splitting)
  }
  // BB1 is the exit block (since gcov 4.8)

This patch adds a synthetic entry block (like PGOInstrumentation and GCC) and
inserts an edge from the synthetic entry block to the original entry block. We
can thus remove the tricky `shouldKeepInEntry` and entry block splitting. The
number of basic blocks does not change, but the emitted .gcno files will be
smaller because we can save one GCOV_TAG_LINES tag.

  // BB0 is the synthetic entry block with a single edge to BB2
  int main() { // BB2
    return 0;  // BB2
  }
  // BB1 is the exit block (since gcov 4.8)
2020-09-09 12:25:24 -07:00
Fangrui Song
b5ef137c11 [gcov] Increment counters with atomicrmw if -fsanitize=thread
Without this patch, `clang --coverage -fsanitize=thread` may fail spuriously
because non-atomic counter increments can be detected as data races.
2020-08-28 16:32:35 -07:00
Fangrui Song
fae221e7ad [gcov] Simplify/speed up CFG hash calculation 2020-07-26 21:15:33 -07:00
Fangrui Song
5809a32e7c [gcov] Add __gcov_dump/__gcov_reset and delete __gcov_flush
GCC r187297 (2012-05) introduced `__gcov_dump` and `__gcov_reset`.
  `__gcov_flush = __gcov_dump + __gcov_reset`

The resolution to https://gcc.gnu.org/PR93623 ("No need to dump gcdas when forking" target GCC 11.0) removed the unuseful and undocumented __gcov_flush.

Close PR38064.

Reviewed By: calixte, serge-sans-paille

Differential Revision: https://reviews.llvm.org/D83149
2020-07-18 15:07:46 -07:00
serge-sans-paille
ffee804053 Correctly track GCOVProfiling IR update
Differential Revision: https://reviews.llvm.org/D82742
2020-07-01 09:30:59 +02:00
serge-sans-paille
ef1a7f2f01 Update pass status for GCOVProfiling
Take fork/exec instrumentation into account.

Differential Revision: https://reviews.llvm.org/D81227
2020-06-09 14:23:30 +02:00
Fangrui Song
e3200dab60 [gcov] Support .gcno/.gcda in gcov 8, 9 or 10 compatible formats 2020-06-07 11:27:49 -07:00
Fangrui Song
693ff89f47 [gcov] Delete unneeded code 2020-06-06 20:36:46 -07:00
Fangrui Song
cdd683b516 [gcov] Support big-endian .gcno and simplify version handling in .gcda 2020-06-06 11:01:47 -07:00
Fangrui Song
b56b1e67e3 [gcov] Default coverage version to '408*' and delete CC1 option -coverage-exit-block-before-body
gcov 4.8 (r189778) moved the exit block from the last to the second.
The .gcda format is compatible with 4.7 but

* decoding libgcov 4.7 produced .gcda with gcov [4.7,8) can mistake the
  exit block, emit bogus `%s:'%s' has arcs from exit block\n` warnings,
  and print wrong `" returned %s` for branch statistics (-b).
* decoding libgcov 4.8 produced .gcda with gcov 4.7 has similar issues.

Also, rename "return block" to "exit block" because the latter is the
appropriate term.
2020-05-12 09:14:03 -07:00
Fangrui Song
25544ce2df [gcov] Default coverage version to '407*' and delete CC1 option -coverage-cfg-checksum
Defaulting to -Xclang -coverage-version='407*' makes .gcno/.gcda
compatible with gcov [4.7,8)

In addition, delete clang::CodeGenOptionsBase::CoverageExtraChecksum and GCOVOptions::UseCfgChecksum.
We can infer the information from the version.

With this change, .gcda files produced by `clang --coverage a.o` linked executable can be read by gcov 4.7~7.
We don't need other -Xclang -coverage* options.
There may be a mismatching version warning, though.

(Note, GCC r173147 "split checksum into cfg checksum and line checksum"
 made gcov 4.7 incompatible with previous versions.)
2020-05-10 16:14:07 -07:00
Fangrui Song
13a633b438 [gcov] Delete CC1 option -coverage-no-function-names-in-data
rL144865 incorrectly wrote function names for GCOV_TAG_FUNCTION
(this might be part of the reasons the header says
"We emit files in a corrupt version of GCOV's "gcda" file format").

rL176173 and rL177475 realized the problem and introduced -coverage-no-function-names-in-data
to work around the issue. (However, the description is wrong.
libgcov never writes function names, even before GCC 4.2).

In reality, the linker command line has to look like:

clang --coverage -Xclang -coverage-version='407*' -Xclang -coverage-cfg-checksum -Xclang -coverage-no-function-names-in-data

Failing to pass -coverage-no-function-names-in-data can make gcov 4.7~7
either produce wrong results (for one gcov-4.9 program, I see "No executable lines")
or segfault (gcov-7).
(gcov-8 uses an incompatible format.)

This patch deletes -coverage-no-function-names-in-data and the related
function names support from libclang_rt.profile
2020-05-10 12:37:44 -07:00
Calixte Denizet
bec223a9bc [profile] Don't crash when forking in several threads
Summary:
When forking in several threads, the counters were written out in using the same global static variables (see GCDAProfiling.c): that leads to crashes.
So when there is a fork, the counters are resetted in the child process and they will be dumped at exit using the interprocess file locking.
When there is an exec, the counters are written out and in case of failures they're resetted.

Reviewers: jfb, vsk, marco-c, serge-sans-paille

Reviewed By: marco-c, serge-sans-paille

Subscribers: llvm-commits, serge-sans-paille, dmajor, cfe-commits, hiraditya, dexonsmith, #sanitizers, marco-c, sylvestre.ledru

Tags: #sanitizers, #clang, #llvm

Differential Revision: https://reviews.llvm.org/D78477
2020-05-07 14:13:11 +02:00
Hans Wennborg
546918cbb4 Revert "[compiler-rt] Add a critical section when flushing gcov counters"
See discussion on PR44792.

This reverts commit 02ce9d8ef5a84bc884de4105eae5f8736ef67634.

It also reverts the follow-up commits
8f46269f0 "[profile] Don't dump counters when forking and don't reset when calling exec** functions"
62c7d8402 "[profile] gcov_mutex must be static"
2020-02-26 13:27:44 +01:00
Calixte Denizet
8f46269f0c [profile] Don't dump counters when forking and don't reset when calling exec** functions
Summary:
There is no need to write out gcdas when forking because we can just reset the counters in the parent process.
Let say a counter is N before the fork, then fork and this counter is set to 0 in the child process.
In the parent process, the counter is incremented by P and in the child process it's incremented by C.
When dump is ran at exit, parent process will dump N+P for the given counter and the child process will dump 0+C, so when the gcdas are merged the resulting counter will be N+P+C.
About exec** functions, since the current process is replaced by an another one there is no need to reset the counters but just write out the gcdas since the counters are definitely lost.
To avoid to have lists in a bad state, we just lock them during the fork and the flush (if called explicitely) and lock them when an element is added.

Reviewers: marco-c

Reviewed By: marco-c

Subscribers: hiraditya, cfe-commits, #sanitizers, llvm-commits, sylvestre.ledru

Tags: #clang, #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D74953
2020-02-24 10:38:33 +01:00
Benjamin Kramer
adcd026838 Make llvm::StringRef to std::string conversions explicit.
This is how it should've been and brings it more in line with
std::string_view. There should be no functional change here.

This is mostly mechanical from a custom clang-tidy check, with a lot of
manual fixups. It uncovers a lot of minor inefficiencies.

This doesn't actually modify StringRef yet, I'll do that in a follow-up.
2020-01-28 23:25:25 +01:00
Alexandre Ganea
478ad94c8e [GCOV] Skip artificial functions from being emitted
This is a patch to support  D66328, which was reverted until this lands.

Enable a compiler-rt test that used to fail previously with D66328.

Differential Revision: https://reviews.llvm.org/D67283
2019-11-15 14:23:11 -05:00
Simon Pilgrim
edfc94e296 GCOVProfiling - fix uninitialized variable warnings + make getFuncChecksum() const. NFCI. 2019-11-14 14:21:18 +00:00
Reid Kleckner
05da2fe521 Sink all InitializePasses.h includes
This file lists every pass in LLVM, and is included by Pass.h, which is
very popular. Every time we add, remove, or rename a pass in LLVM, it
caused lots of recompilation.

I found this fact by looking at this table, which is sorted by the
number of times a file was changed over the last 100,000 git commits
multiplied by the number of object files that depend on it in the
current checkout:
  recompiles    touches affected_files  header
  342380        95      3604    llvm/include/llvm/ADT/STLExtras.h
  314730        234     1345    llvm/include/llvm/InitializePasses.h
  307036        118     2602    llvm/include/llvm/ADT/APInt.h
  213049        59      3611    llvm/include/llvm/Support/MathExtras.h
  170422        47      3626    llvm/include/llvm/Support/Compiler.h
  162225        45      3605    llvm/include/llvm/ADT/Optional.h
  158319        63      2513    llvm/include/llvm/ADT/Triple.h
  140322        39      3598    llvm/include/llvm/ADT/StringRef.h
  137647        59      2333    llvm/include/llvm/Support/Error.h
  131619        73      1803    llvm/include/llvm/Support/FileSystem.h

Before this change, touching InitializePasses.h would cause 1345 files
to recompile. After this change, touching it only causes 550 compiles in
an incremental rebuild.

Reviewers: bkramer, asbirlea, bollu, jdoerfert

Differential Revision: https://reviews.llvm.org/D70211
2019-11-13 16:34:37 -08:00
Teresa Johnson
9c27b59cec Change TargetLibraryInfo analysis passes to always require Function
Summary:
This is the first change to enable the TLI to be built per-function so
that -fno-builtin* handling can be migrated to use function attributes.
See discussion on D61634 for background. This is an enabler for fixing
handling of these options for LTO, for example.

This change should not affect behavior, as the provided function is not
yet used to build a specifically per-function TLI, but rather enables
that migration.

Most of the changes were very mechanical, e.g. passing a Function to the
legacy analysis pass's getTLI interface, or in Module level cases,
adding a callback. This is similar to the way the per-function TTI
analysis works.

There was one place where we were looking for builtins but not in the
context of a specific function. See FindCXAAtExit in
lib/Transforms/IPO/GlobalOpt.cpp. I'm somewhat concerned my workaround
could provide the wrong behavior in some corner cases. Suggestions
welcome.

Reviewers: chandlerc, hfinkel

Subscribers: arsenm, dschuff, jvesely, nhaehnle, mehdi_amini, javed.absar, sbc100, jgravelle-google, eraman, aheejin, steven_wu, george.burgess.iv, dexonsmith, jfb, asbirlea, gchatelet, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66428

llvm-svn: 371284
2019-09-07 03:09:36 +00:00
Jonas Devlieghere
0eaee545ee [llvm] Migrate llvm::make_unique to std::make_unique
Now that we've moved to C++14, we no longer need the llvm::make_unique
implementation from STLExtras.h. This patch is a mechanical replacement
of (hopefully) all the llvm::make_unique instances across the monorepo.

llvm-svn: 369013
2019-08-15 15:54:37 +00:00
Fangrui Song
d9b948b6eb Rename F_{None,Text,Append} to OF_{None,Text,Append}. NFC
F_{None,Text,Append} are kept for compatibility since r334221.

llvm-svn: 367800
2019-08-05 05:43:48 +00:00