| Age | Commit message (Collapse) | Author | Files | Lines |
|---|
|
This pull request fixes coverage mapping on GPU targets.
- It adds an address space cast to the coverage mapping generation pass.
- It reads the profiled function names from the ELF directly. Reading it
from public globals was causing issues in cases where multiple
device-code object files are linked together.
|
|
## Purpose
This patch is one in a series of code-mods that annotate LLVM’s public
interface for export. This patch annotates the `llvm/Transforms`
library. These annotations currently have no meaningful impact on the
LLVM build; however, they are a prerequisite to support an LLVM Windows
DLL (shared library) build.
## Background
This effort is tracked in #109483. Additional context is provided in
[this
discourse](https://discourse.llvm.org/t/psa-annotating-llvm-public-interface/85307),
and documentation for `LLVM_ABI` and related annotations is found in the
LLVM repo
[here](https://github.com/llvm/llvm-project/blob/main/llvm/docs/InterfaceExportAnnotations.rst).
The bulk of these changes were generated automatically using the
[Interface Definition Scanner (IDS)](https://github.com/compnerd/ids)
tool, followed formatting with `git clang-format`.
The following manual adjustments were also applied after running IDS on
Linux:
- Removed a redundant `operator<<` from Attributor.h. IDS only
auto-annotates the 1st declaration, and the 2nd declaration being
un-annotated resulted in an "inconsistent linkage" error on Windows when
building LLVM as a DLL.
- `#include` the `VirtualFileSystem.h` in PGOInstrumentation.h and
remove the local declaration of the `vfs::FileSystem` class. This is
required because exporting the `PGOInstrumentationUse` constructor
requires the class be fully defined because it is used by an argument.
- Add #include "llvm/Support/Compiler.h" to files where it was not
auto-added by IDS due to no pre-existing block of include statements.
- Add `LLVM_TEMPLATE_ABI` and `LLVM_EXPORT_TEMPLATE` to exported
instantiated templates.
## Validation
Local builds and tests to validate cross-platform compatibility. This
included llvm, clang, and lldb on the following configurations:
- Windows with MSVC
- Windows with Clang
- Linux with GCC
- Linux with Clang
- Darwin with Clang
|
|
|
|
Not needed with opaque pointers.
|
|
|
|
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.
|
|
As part of the "RemoveDIs" project, BasicBlock::iterator now carries a
debug-info bit that's needed when getFirstNonPHI and similar feed into
instruction insertion positions. Call-sites where that's necessary were
updated a year ago; but to ensure some type safety however, we'd like to
have all calls to moveBefore use iterators.
This patch adds a (guaranteed dereferenceable) iterator-taking
moveBefore, and changes a bunch of call-sites where it's obviously safe
to change to use it by just calling getIterator() on an instruction
pointer. A follow-up patch will contain less-obviously-safe changes.
We'll eventually deprecate and remove the instruction-pointer
insertBefore, but not before adding concise documentation of what
considerations are needed (very few).
|
|
Identified with misc-include-cleaner.
|
|
This corrects a couple off by ones related to the sampling of
**instrumented** counters, and enables setting 100% rates for burst
sampling (burst duration = period).
Off by ones:
Prior to this change it was impossible to set a period of 65535 because
this was converted to fast sampling which rollsover at USHRT_MAX + 1
(65536). Similarly the burst durations would collect burst duration + 1
counts as they used an ULE comparison.
100% sampling:
Although this is not useful for a productionized use case, it does allow
for more deterministic testing with the sampling checks in place. After
all the off by ones are fixed, allowing for 100% sampling is a matter of
letting burst duration = period.
|
|
Add `Intrinsic::getDeclarationIfExists` to lookup an existing
declaration of an intrinsic in a `Module`.
|
|
Currently, WebAssembly/WASI target does not provide direct support for
code coverage.
This patch set fixes several issues to unlock the feature. The main
changes are:
1. Port `compiler-rt/lib/profile` to WebAssembly/WASI.
2. Adjust profile metadata sections for Wasm object file format.
- [CodeGen] Emit `__llvm_covmap` and `__llvm_covfun` as custom sections
instead of data segments.
- [lld] Align the interval space of custom sections at link time.
- [llvm-cov] Copy misaligned custom section data if the start address is
not aligned.
- [llvm-cov] Read `__llvm_prf_names` from data segments
3. [clang] Link with profile runtime libraries if requested
See each commit message for more details and rationale.
This is part of the effort to add code coverage support in Wasm target
of Swift toolchain.
|
|
Per the discussion in #102542, it is safe to insert BBs under
`lowerIntrinsics()` since #69535 has made tolerant of modifying BBs.
So, I can get rid of using the inlined function `rmw_or`, introduced in
#96040.
|
|
It is almost always simpler to use {} instead of std::nullopt to
initialize an empty ArrayRef. This patch changes all occurrences I could
find in LLVM itself. In future the ArrayRef(std::nullopt_t) constructor
could be deprecated or removed.
|
|
Utility functions have been moved out to Utils. Minor opportunity to
drop the header where not needed.
|
|
This pull request is a revised version of #76587. This pull request
fixes some build issues that were present in the previous version of
this change.
> This pull request is the first part of an ongoing effort to extends
PGO instrumentation to GPU device code. This PR makes the following
changes:
>
> - Adds blank registration functions to device RTL
> - Gives PGO globals protected visibility when targeting a supported
GPU
> - Handles any addrspace casts for PGO calls
> - Implements PGO global extraction in GPU plugins (currently only
dumps info)
>
> These changes can be tested by supplying `-fprofile-instrument=clang`
while targeting a GPU.
|
|
This patch adds support for conditional counter updates in single byte
counters mode to reduce the write contention by first checking whether
the counter is set before overwriting it.
---------
Co-authored-by: Juan Manuel Martinez Caamaño <jmartinezcaamao@gmail.com>
|
|
`counter_bias` is incompatible to Bitmap. The distance between Counters
and Bitmap is different between on-memory sections and profraw image.
Reference to `__llvm_profile_bitmap_bias` is generated only if
`-fcoverge-mcdc` `-runtime-counter-relocation` are specified. The
current implementation rejected their options.
```
Runtime counter relocation is presently not supported for MC/DC bitmaps
```
|
|
In comparison to non-instrumented binaries, PGO instrumentation binaries
can be significantly slower. For highly threaded programs, this slowdown
can
reach 10x due to data races or false sharing within counters.
This patch incorporates sampling into the PGO instrumentation process to
enhance the speed of instrumentation binaries. The fundamental concept
is similar to the one proposed in https://reviews.llvm.org/D63949.
Three sampling modes are introduced:
1. Simple Sampling: When '-sampled-instr-bust-duration' is set to 1.
2. Fast Burst Sampling: When not using simple sampling, and
'-sampled-instr-period' is set to 65535. This is the default mode of
sampling.
3. Full Burst Sampling: When neither simple nor fast burst sampling is
used.
Utilizing this sampled instrumentation significantly improves the
binary's
execution speed. Measurements show up to 5x speedup with default
settings. Fast burst sampling now results in only around 20% to 30%
slowdown (compared to 8 to 10x slowdown without sampling).
Out tests show that profile quality remains good with sampling,
with edge counts typically showing more than 90% overlap.
For applications whose behavior changes due to binary speed,
sampling instrumentation can enhance performance.
Observations have shown some apps experiencing up to
a ~2% improvement in PGO.
A potential drawback of this patch is the increased binary size
and compilation time. The Sampling method in this patch does
not improve single threaded program instrumentation binary
speed.
|
|
Bias doesn't change after startup.
The test is enhanced for optimized sequences and atomic ops.
|
|
This reverts commit 5fd2af38e461445c583d7ffc2fe23858966eee76. It caused build issues and broke the buildbot.
|
|
This pull request is the first part of an ongoing effort to extends PGO
instrumentation to GPU device code. This PR makes the following changes:
- Adds blank registration functions to device RTL
- Gives PGO globals protected visibility when targeting a supported GPU
- Handles any addrspace casts for PGO calls
- Implements PGO global extraction in GPU plugins (currently only dumps
info)
These changes can be tested by supplying `-fprofile-instrument=clang`
while targeting a GPU.
|
|
This also introduces "Test and conditional Read-Modify-Write". The flow
to `atomicrmw or` is marked as `unlikely`.
|
|
`rmw_or` is defined as "private alwaysinline". At the moment, it has
just only simple "Read, Or, and Write", which is just same as the
current implementation.
|
|
|
|
(#95692)
|
|
3rd arg of `tvbitmap.update` was made unused. Remove 3rd arg.
Sweep `condbitmap.update`, since it is no longer used.
|
|
By storing possible test vectors instead of combinations of conditions,
the restriction is dramatically relaxed.
This introduces two options to `cc1`:
* `-fmcdc-max-conditions=32767`
* `-fmcdc-max-test-vectors=2147483646`
This change makes coverage mapping, profraw, and profdata incompatible
with Clang-18.
- Bitmap semantics changed. It is incompatible with previous format.
- `BitmapIdx` in `Decision` points to the end of the bitmap.
- Bitmap is packed per function.
- `llvm-cov` can understand `profdata` generated by `llvm-profdata-18`.
RFC:
https://discourse.llvm.org/t/rfc-coverage-new-algorithm-and-file-format-for-mc-dc/76798
--
Change(s) since llvmorg-19-init-14288-g7ead2d8c7e91
- Update compiler-rt/test/profile/ContinuousSyncMode/image-with-mcdc.c
|
|
This broke the lit tests on Mac:
https://green.lab.llvm.org/job/llvm.org/job/clang-stage1-RA/1096/
> By storing possible test vectors instead of combinations of conditions,
> the restriction is dramatically relaxed.
>
> This introduces two options to `cc1`:
>
> * `-fmcdc-max-conditions=32767`
> * `-fmcdc-max-test-vectors=2147483646`
>
> This change makes coverage mapping, profraw, and profdata incompatible
> with Clang-18.
>
> - Bitmap semantics changed. It is incompatible with previous format.
> - `BitmapIdx` in `Decision` points to the end of the bitmap.
> - Bitmap is packed per function.
> - `llvm-cov` can understand `profdata` generated by `llvm-profdata-18`.
>
> RFC:
> https://discourse.llvm.org/t/rfc-coverage-new-algorithm-and-file-format-for-mc-dc/76798
This reverts commit 7ead2d8c7e9114b3f23666209a1654939987cb30.
|
|
By storing possible test vectors instead of combinations of conditions,
the restriction is dramatically relaxed.
This introduces two options to `cc1`:
* `-fmcdc-max-conditions=32767`
* `-fmcdc-max-test-vectors=2147483646`
This change makes coverage mapping, profraw, and profdata incompatible
with Clang-18.
- Bitmap semantics changed. It is incompatible with previous format.
- `BitmapIdx` in `Decision` points to the end of the bitmap.
- Bitmap is packed per function.
- `llvm-cov` can understand `profdata` generated by `llvm-profdata-18`.
RFC:
https://discourse.llvm.org/t/rfc-coverage-new-algorithm-and-file-format-for-mc-dc/76798
|
|
(#66825)
(The profile format change is split into a standalone change into https://github.com/llvm/llvm-project/pull/81691)
* For InstrFDO value profiling, implement instrumentation and lowering for virtual table address.
* This is controlled by `-enable-vtable-value-profiling` and off by default.
* When the option is on, raw profiles will carry serialized `VTableProfData` structs and compressed vtables as payloads.
* Implement profile reader and writer support
* Raw profile reader is used by `llvm-profdata` but not compiler. Raw profile reader will construct InstrProfSymtab with symbol names, and map profiled runtime address to vtable symbols.
* Indexed profile reader is used by `llvm-profdata` and compiler. When initialized, the reader stores a pointer to the beginning of in-memory compressed vtable names and the length of string. When used in `llvm-profdata`, reader decompress the string to show symbols of a profiled site. When used in compiler, string decompression doesn't
happen since IR is used to construct InstrProfSymtab.
* Indexed profile writer collects the list of vtable names, and stores that to index profiles.
* Text profile reader and writer support are added but mostly follow the implementation for indirect-call value type.
* `llvm-profdata show -show-vtables <args> <profile>` is implemented.
rfc in
https://discourse.llvm.org/t/rfc-dynamic-type-profiling-and-optimizations-in-llvm/74600#pick-instrumentation-points-and-instrument-runtime-types-7
|
|
to the code (#83757)
|
|
everywhere (#83756)
|
|
|
|
(#77225)
Whether runtime registration is needed is not dependent on the OS but
the file format. For ELF, COFF, Mach-O or XCOFF, we can always use the
linker support. This is important for baremetal platforms such as RTOS
and UEFI platforms where there is no OS but we still don't want to use
runtime registration and rely on linker support instead.
|
|
## Motivation
Since we don't need the metadata sections at runtime, we can somehow
offload them from memory at runtime. Initially, I explored [debug info
correlation](https://discourse.llvm.org/t/instrprofiling-lightweight-instrumentation/59113),
which is used for PGO with value profiling disabled. However, it
currently only works with DWARF and it's be hard to add such artificial
debug info for every function in to CodeView which is used on Windows.
So, offloading profile metadata sections at runtime seems to be a
platform independent option.
## Design
The idea is to use new section names for profile name and data sections
and mark them as metadata sections. Under this mode, the new sections
are non-SHF_ALLOC in ELF. So, they are not loaded into memory at runtime
and can be stripped away as a post-linking step. After the process
exits, the generated raw profiles will contains only headers + counters.
llvm-profdata can be used correlate raw profiles with the unstripped
binary to generate indexed profile.
## Data
For chromium base_unittests with code coverage on linux, the binary size
overhead due to instrumentation reduced from 64M to 38.8M (39.4%) and
the raw profile files size reduce from 128M to 68M (46.9%)
```
$ bloaty out/cov/base_unittests.stripped -- out/no-cov/base_unittests.stripped
FILE SIZE VM SIZE
-------------- --------------
+121% +30.4Mi +121% +30.4Mi .text
[NEW] +14.6Mi [NEW] +14.6Mi __llvm_prf_data
[NEW] +10.6Mi [NEW] +10.6Mi __llvm_prf_names
[NEW] +5.86Mi [NEW] +5.86Mi __llvm_prf_cnts
+95% +1.75Mi +95% +1.75Mi .eh_frame
+108% +400Ki +108% +400Ki .eh_frame_hdr
+9.5% +211Ki +9.5% +211Ki .rela.dyn
+9.2% +95.0Ki +9.2% +95.0Ki .data.rel.ro
+5.0% +87.3Ki +5.0% +87.3Ki .rodata
[ = ] 0 +13% +47.0Ki .bss
+40% +1.78Ki +40% +1.78Ki .got
+12% +1.49Ki +12% +1.49Ki .gcc_except_table
[ = ] 0 +65% +1.23Ki .relro_padding
+62% +1.20Ki [ = ] 0 [Unmapped]
+13% +448 +19% +448 .init_array
+8.8% +192 [ = ] 0 [ELF Section Headers]
+0.0% +136 +0.0% +80 [7 Others]
+0.1% +96 +0.1% +96 .dynsym
+1.2% +96 +1.2% +96 .rela.plt
+1.5% +80 +1.2% +64 .plt
[ = ] 0 -99.2% -3.68Ki [LOAD #5 [RW]]
+195% +64.0Mi +194% +64.0Mi TOTAL
$ bloaty out/cov-cor/base_unittests.stripped -- out/no-cov/base_unittests.stripped
FILE SIZE VM SIZE
-------------- --------------
+121% +30.4Mi +121% +30.4Mi .text
[NEW] +5.86Mi [NEW] +5.86Mi __llvm_prf_cnts
+95% +1.75Mi +95% +1.75Mi .eh_frame
+108% +400Ki +108% +400Ki .eh_frame_hdr
+9.5% +211Ki +9.5% +211Ki .rela.dyn
+9.2% +95.0Ki +9.2% +95.0Ki .data.rel.ro
+5.0% +87.3Ki +5.0% +87.3Ki .rodata
[ = ] 0 +13% +47.0Ki .bss
+40% +1.78Ki +40% +1.78Ki .got
+12% +1.49Ki +12% +1.49Ki .gcc_except_table
+13% +448 +19% +448 .init_array
+0.1% +96 +0.1% +96 .dynsym
+1.2% +96 +1.2% +96 .rela.plt
+1.2% +64 +1.2% +64 .plt
+2.9% +64 [ = ] 0 [ELF Section Headers]
+0.0% +40 +0.0% +40 .data
+1.2% +32 +1.2% +32 .got.plt
+0.0% +24 +0.0% +8 [5 Others]
[ = ] 0 -22.9% -872 [LOAD #5 [RW]]
-74.5% -1.44Ki [ = ] 0 [Unmapped]
[ = ] 0 -76.5% -1.45Ki .relro_padding
+118% +38.8Mi +117% +38.8Mi TOTAL
```
A few things to note:
1. llvm-profdata doesn't support filter raw profiles by binary id yet,
so when a raw profile doesn't belongs to the binary being digested by
llvm-profdata, merging will fail. Once this is implemented,
llvm-profdata should be able to only merge raw profiles with the same
binary id as the binary and discard the rest (with mismatched/missing
binary id). The workflow I have in mind is to have scripts invoke
llvm-profdata to get all binary ids for all raw profiles, and
selectively choose the raw pnrofiles with matching binary id and the
binary to llvm-profdata for merging.
2. Note: In COFF, currently they are still loaded into memory but not
used. I didn't do it in this patch because I noticed that `.lcovmap` and
`.lcovfunc` are loaded into memory. A separate patch will address it.
3. This should works with PGO when value profiling is disabled as debug
info correlation currently doing, though I haven't tested this yet.
|
|
Captures its responsibility a bit better.
|
|
|
|
Akin other passes - refactored the name to `InstrProfilingLoweringPass` to better communicate what it does, and split the pass part and the transformation part to avoid needing to initialize object state during `::run`.
A subsequent PR will move `InstrLowering` to the .cpp file and rename it to `InstrLowerer`.
|
|
We'd like to make various instrprof globals large to make them not
contribute to relocation pressure since there are no direct accesses
to them in the module.
Similar to what was done for asan_globals in #74514.
This affects the __llvm_prf_vals, __llvm_prf_vnds, and __llvm_prf_names
sections.
The reland fixes platform.ll.
|
|
This reverts commit 5507f70cc205a7ec21d264a64c703b3d314b998c.
Breaks bots, e.g. https://lab.llvm.org/buildbot/#/builders/232/builds/16374
|
|
We'd like to make various instrprof globals large to make them not
contribute to relocation pressure since there are no direct accesses
to them in the module.
Similar to what was done for asan_globals in #74514.
This affects the __llvm_prf_vals, __llvm_prf_vnds, and __llvm_prf_names
sections.
|
|
If a suspend happens in the resume part (this can happen in the case of chained coroutines), and that's part of a loop, the pre-split CFG has the suspend block as an exit of that loop. PGO Counter Promotion will then try to commit the temporary counter to the global in that "exit" block (it also does that in the other loop exit BBs, which also includes
the "destroy" case). This interferes with symmetric transfer.
We don't need to commit the counter in the suspend case - it's not a loop exit from the perspective of the behavior of the program. The regular loop exit, together with the "destroy" case, completely cover any updates that may need to happen to the global counter.
|
|
Fix stale comment.
|
|
Opaque ptr cleanup effort (NFC).
|
|
getInt8PtrTy. NFC
After opaque pointer migration, getInt8PtrTy() is considered legacy.
Replace it with getPtrTy(), and while here, remove some unneeded pointer
casts.
|
|
functions (#72069)
Fixes a bug introduced by
commit f95b2f1acf11 ("Reland [InstrProf][compiler-rt] Enable MC/DC
Support in LLVM Source-based Code Coverage (1/3)")
The InstrProfiling pass was refactored when introducing support for
MC/DC such that the creation of the data variable was abstracted and
called only once per function from ::run(). Because ::run() only
iterated over functions there were not fully inlined, and because it
only created the data variable for the first intrinsic that it saw, data
variables corresponding to functions fully inlined into other
instrumented callers would end up without a data variable, resulting in
loss of coverage information. This patch does the following:
1.) Move the call of createDataVariable() to getOrCreateRegionCounters()
so that the creation of the data variable will happen indirectly either
from ::new() or during profile intrinsic lowering when it is needed.
This effectively restores the behavior prior to the refactor and ensures
that all data variables are created when needed (and not duplicated).
2.) Process all MC/DC bitmap parameter intrinsics in ::run() prior to
calling getOrCreateRegionCounters(). This ensures bitmap regions are
created for each function including functions that are fully inlined. It
also ensures that the bitmap region is created for each function prior
to the creation of the data variable because it is referenced by the
data variable. Again, duplication is prevented if the same parameter
intrinsic is inlined into multiple functions.
3.) No longer pass the MC/DC intrinsic to createDataVariable(). This
decouples the creation of the data variable from a specific MC/DC
intrinsic. Instead, with #2 above, store the number of bitmap bytes
required in the PerFunctionProfileData in the ProfileDataMap along with
the function's CounterRegion and BitmapRegion variables. This ties the
bitmap information directly to the function to which it belongs, and the
data variable created for that function can reference that.
|
|
Opaque ptr cleanup effort (NFC).
|
|
Fixes a bug introduced by
commit f95b2f1acf11 ("Reland [InstrProf][compiler-rt] Enable MC/DC
Support in LLVM Source-based Code Coverage (1/3)")
createDataVariable() needs to check that a data variable wasn't already
created before creating it. Previously, this was done inadvertantly in
getOrCreateRegionCounters(), which checked that the RegionCounters was
not created multiple times before creating the counter section and the
data variable. When the creation of the data variable was abstracted
into its own function (createDataVariable()), there was no corresponding
check. This was failing on a case in which an instrumented function was
being inlined into multiple functions and a duplicate data variable was
created, which led to a segfault in emitNameData(). Test case added
based on the repro that also ensures a single data variable was created
in this case.
|
|
Replace this with PointerType::getUnqual().
Followup to the opaque pointer transition. Fixes an in-code TODO item.
|
|
startswith/endswith. NFC.
startswith/endswith wrap starts_with/ends_with and will eventually go away (to more closely match string_view)
|
