These are identified by misc-include-cleaner. I've filtered out those
that break builds. Also, I'm staying away from llvm-config.h,
config.h, and Compiler.h, which likely cause platform- or
compiler-specific build failures.
In the current gcov implementation, all lines within a basic block are
attributed to the source file of the block's containing function. This
is inaccurate when a block contains lines from other files (e.g., via
#include "foo.inc").
Commit
[406e81b](406e81b79d)
attempted to address this by filtering lines based on debug info types,
but this approach has two limitations:
* **Over-filtering**: Some valid lines belonging to the function are
incorrectly excluded.
* **Under-counting**: Lines not belonging to the function are filtered
out and omitted from coverage statistics.
**GCC Reference Behavior**
GCC's gcov implementation handles this case correctly.This change aligns
the LLVM behavior with GCC.
**Proposed Solution**
1. **GCNO Generation**:
* **Current**: Each block stores a single GCOVLines record (filename +
lines).
* **New**: Dynamically create new GCOVLines records whenever consecutive
lines in a block originate from different source files. Group subsequent
lines from the same file under one record.
2. **GCNO Parsing**:
* **Current**: Lines are directly attributed to the function's source
file.
* **New**: Introduce a GCOVLocation type to track filename/line mappings
within blocks. Statistics will reflect the actual source file for each
line.
Seeing how we can't generate any debug intrinsics any more: delete a
variety of codepaths where they're handled. For the most part these are
plain deletions, in others I've tweaked comments to remain coherent, or
added a type to (what was) type-generic-lambdas.
This isn't all the DbgInfoIntrinsic call sites but it's most of the
simple scenarios.
Co-authored-by: Nikita Popov <github@npopov.com>
This implements the result of the discussion at:
https://discourse.llvm.org/t/rfc-report-fatal-error-and-the-default-value-of-gencrashdialog/73587
There are two different use cases for report_fatal_error, so replace it
with two functions reportFatalInternalError() and
reportFatalUsageError(). The former indicates a bug in LLVM and
generates a crash dialog. The latter does not. The names have been
suggested by rnk and people seemed to like them.
This replaces a lot of the usages that passed an explicit value for
GenCrashDiag. I did not bulk replace remaining report_fatal_error usage
-- they probably require case by case review for which function to use.
The module currently stores the target triple as a string. This means
that any code that wants to actually use the triple first has to
instantiate a Triple, which is somewhat expensive. The change in #121652
caused a moderate compile-time regression due to this. While it would be
easy enough to work around, I think that architecturally, it makes more
sense to store the parsed Triple in the module, so that it can always be
directly queried.
For this change, I've opted not to add any magic conversions between
std::string and Triple for backwards-compatibilty purses, and instead
write out needed Triple()s or str()s explicitly. This is because I think
a decent number of them should be changed to work on Triple as well, to
avoid unnecessary conversions back and forth.
The only interesting part in this patch is that the default triple is
Triple("") instead of Triple() to preserve existing behavior. The former
defaults to using the ELF object format instead of unknown object
format. We should fix that as well.
The gcov version is set to 11.1 (compatible with gcov 9) even if
`-Xclang -coverage-version=` specified version is less than 11.1.
Therefore, we can drop producer support for version < 11.1.
This patch extends the PGO infrastructure with an option to prefer the
instrumentation of loop entry blocks.
This option is a generalization of
19fb5b467b,
and helps to cover cases where the loop exit is never executed.
An example where this can occur are event handling loops.
Note that change does NOT change the default behavior.
This PR registers the writeout and reset functions for `gcov` for all
modules in the PGO runtime, instead of registering them
using global constructors in each module. The change is made for AIX
only, but the same mechanism works on Linux on Power.
When registering such functions using global constructors in each module
without `-ffunction-sections`, the AIX linker cannot garbage collect
unused undefined symbols, because such symbols are grouped in the same
section as the `__sinit` symbol. Keeping such undefined symbols causes
link errors (see test case
https://github.com/llvm/llvm-project/pull/108570/files#diff-500a7e1ba871e1b6b61b523700d5e30987900002add306e1b5e4972cf6d5a4f1R1
for this scenario). This PR implements the initialization in the
runtime, hence avoiding introducing `__sinit` into each module.
The implementation adds a new global variable `__llvm_covinit_functions`
to each module. This new global variable contains the function pointers
to the `Writeout` and `Reset` functions. `__llvm_covinit_functions`'s
section is the named section `__llvm_covinit`. The linker will aggregate
all the `__llvm_covinit` sections from each module
to form one single named section in the final binary. The pair of
functions
```
const __llvm_gcov_init_func_struct *__llvm_profile_begin_covinit();
const __llvm_gcov_init_func_struct *__llvm_profile_end_covinit();
```
are implemented to return the start and end address of this named
section in the final binary, and they are used in function
```
__llvm_profile_gcov_initialize()
```
(which is a constructor function in the runtime) so the runtime knows
the addresses of all the `Writeout` and `Reset` functions from all the
modules.
One noticeable implementation detail relevant to AIX is that to preserve
the `__llvm_covinit` from the linker's garbage collection, a `.ref`
pseudo instruction is inserted into them, referring to the section that
contains the `__llvm_gcov_ctr` variables, which are used in the
instrumented code. The `__llvm_gcov_ctr` variables did not belong to
named sections before, but this PR added them to the
`__llvm_gcov_ctr_section` named section, so we can add a `.ref` pseudo
instruction that refers to them in the `__llvm_covinit` section.
Don't call raw_string_ostream::flush(), which is essentially a no-op.
As specified in the docs, raw_string_ostream is always unbuffered.
( 65b13610a5226b84889b923bae884ba395ad084d for further reference )
Uses the new InsertPosition class (added in #94226) to simplify some of
the IRBuilder interface, and removes the need to pass a BasicBlock
alongside a BasicBlock::iterator, using the fact that we can now get the
parent basic block from the iterator even if it points to the sentinel.
This patch removes the BasicBlock argument from each constructor or call
to setInsertPoint.
This has no functional effect, but later on as we look to remove the
`Instruction *InsertBefore` argument from instruction-creation
(discussed
[here](https://discourse.llvm.org/t/psa-instruction-constructors-changing-to-iterator-only-insertion/77845)),
this will simplify the process by allowing us to deprecate the
InsertPosition constructor directly and catch all the cases where we use
instructions rather than iterators.
Now that llvm::support::endianness has been renamed to
llvm::endianness, we can use the shorter form. This patch replaces
support::endianness with llvm::endianness.
Now that llvm::support::endianness has been renamed to
llvm::endianness, we can use the shorter form. This patch replaces
support::endianness::{big,little,native} with
llvm::endianness::{big,little,native}.
Constructs such as inline variables, #line, and #include can create
lexical blocks with a different filename.
GCOVProfiling and llvm-cov gcov currently don't handle such cases (see
GCOVLines::writeOut and GCOVFile::readGCNO) and would incorrectly
attribute the line number to the current file.
For now, ignore such blocks. Missing line execution counts is better
than wrong ones.
---
As a workaround that Apple targets don't use -mconstructor-aliases yet,
allow line execution count 4 on the A::A line (1f34e282e8066281eb1447e21e44a2a2e9983e79).
Constructs such as inline variables, #line, and #include can create
lexical blocks with a different filename.
GCOVProfiling and llvm-cov gcov currently don't handle such cases (see
GCOVLines::writeOut and GCOVFile::readGCNO) and would incorrectly
attribute the line number to the current file.
For now, ignore such blocks. Missing line execution counts is better
than wrong ones.
This patch adds nosantize metadata to memory access instructions inserted by gcov emitProfileNotes(), making sanitizers skip these instructions when gcov and sanitizer are used together.
Reviewed By: nickdesaulniers
Differential Revision: https://reviews.llvm.org/D150460
This commit moves the CFGMST.h file into the include directory. The
implemented algorithm is can be helpful for downstream projects that
want to use the PGO data in a non-standard way.
Reviewed By: gysit
Differential Revision: https://reviews.llvm.org/D149336
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
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
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
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
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
Running iwyu-diff on LLVM codebase since fa5a4e1b95c8f37796 detected a few
regressions, fixing them.
Differential Revision: https://reviews.llvm.org/D124847
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
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
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.
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
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
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
... by using MapVector. The issue was caused by 63182c2ac0b643a60d397274e8a31166fc7243fa.
Also use stable_partition instead of partition to get stable results
across different STL implementations.
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.
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.
