Summary:
Refactor bolt/*/Passes to follow the braces rule for if/else/loop from
[LLVM Coding Standards](https://llvm.org/docs/CodingStandards.html).
(cherry picked from FBD33344642)
Summary:
The lower_bound might return the end iterator, the ignoring of which will
cause memory corruption.
Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei
(cherry picked from FBD33307803)
Summary:
Fix missing string header file inclusion and link_fdata find
problem in lit tests. Change root-level tests to require
linux. Re-enable Windows in our root CMakeLists.txt.
(cherry picked from FBD33296290)
Summary:
Fix according to Coding Standards doc, section Don't Use
Braces on Simple Single-Statement Bodies of if/else/loop Statements.
This set of changes applies to lib Core only.
(cherry picked from FBD33240028)
Summary:
Since nops are now removed in a separate pass, the profile is consumed
on a CFG with nops. If previously a profile was generated without nops,
the offsets in the profile could be different if branches included nops
either as a source or a destination.
This diff adjust offsets to make the profile reading backwards
compatible.
(cherry picked from FBD33231254)
Summary:
The patch moves the shortenInstructions and nop remove to separate binary
passes. As a result when llvm-bolt optimizations stage will begin the
instructions of the binary functions will be absolutely the same as it
was in the binary. This is needed for the golang support by llvm-bolt.
Some of the tests must be changed, since bb alignment nops might create
unreachable BBs in original functions.
Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei
(cherry picked from FBD32896517)
Summary:
This patch adds AArch64 relocations handling in case updating of
debug sections is enabled
Elvina Yakubova,
Advanced Software Technology Lab, Huawei
(cherry picked from FBD33077609)
Summary:
Create a new high-level target named bolt that builds all
BOLT artifacts, as well as a install-bolt target that installs them.
(cherry picked from FBD33133002)
Summary:
Gracefully handle binaries with split functions where two fragments are folded
into one, resulting in a fragment with two parent functions.
This behavior is expected in GCC8+ with -O2 optimization level, where both
function splitting and ICF are enabled by default.
On the BOLT side, the changes are:
- BinaryFunction: allow multiple parent fragments:
- `ParentFragment` --> `ParentFragments`,
- `setParentFragment` --> `addParentFragment`.
- BinaryContext:
- `populateJumpTables`: mark fragments to be skipped later,
- `registerFragment`: add a name heuristic check, return false if it failed,
- `processInterproceduralReferences`: check if `registerFragment`
succeeded, otherwise issue a warning,
- `skipMarkedFragments`: move out fragment traversal and skipping from
`populateJumpTables` into a separate function.
This change fixes an issue where unrelated functions might be registered
as fragments:
```
BOLT-WARNING: interprocedural reference between unrelated fragments:
bad_gs/1(*2) and amd_decode_mce.cold.27/1(*2)
```
(Linux kernel binary)
(cherry picked from FBD32786688)
Summary:
Refactor members of BinaryBasicBlock. Replace some std containers with
ADT equivalents. The size of BinaryBasicBlock on x86-64 Linux is reduced
from 232 bytes to 192 bytes.
(cherry picked from FBD33081850)
Summary:
Build is already broken because VS fails to locate
llvm-boltdiff when running tests, and VS also complains that
include/bolt/Passes/InstrumentationSummary.h is lacking an include
string header. Disable this until we have a Windows buildbot to make
sure this build is sane.
(cherry picked from FBD33039972)
Summary:
Switched members of BinaryFunction to ADT where it was possible and
made sense. As a result, the size of BinaryFunction on x86-64 Linux
reduced from 1624 bytes to 1448.
(cherry picked from FBD32981555)
Summary:
For DWP case the AbbreviationsOffset is the offset of the abbrev
contribution in the DWP file, so can be none zero.
(cherry picked from FBD32961240)
Summary:
Currently, RuntimeDyld will not allocate a section without relocations
even if such a section is marked allocatable and defines symbols.
When we emit .debug_line for compile units with unchanged code, we
output original (input) data, without relocations. If all units are
emitted in this way, we will have no relocations in the emitted
.debug_line. RuntimeDyld will not allocate the section and as a result
we will write an empty .debug_line section.
To workaround the issue, always emit a relocation of RELOC_NONE type
when emitting raw contents to debug_line.
(cherry picked from FBD32909869)
Summary:
Some optimizations may remove all instructions in a basic block.
The pass will cleanup the CFG afterwards by removing empty basic
blocks and merging duplicate CFG edges.
The normalized CFG is printed under '-print-normalized' option.
(cherry picked from FBD32774360)
Summary:
The debug message for the last fall-through block was printed under the
reverse condition, i.e. when the block was not a fall-through. Remove
the debug message. If we'll need such information, we can add a pass
with more analysis, i.e. checking the last instruction, if the block is
reachable, etc.
(cherry picked from FBD32670816)
Summary:
TailDuplication::isInCacheLine makes the assumption that the block
has a valid layout index, which is not the case for unreachable blocks.
Add a check for a valid layout index.
(cherry picked from FBD32659755)
Summary:
In some of the system stack protection is enabled by default, which will
lead in extra symbols dependencies, which we want to avoid.
Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei
(cherry picked from FBD32478426)
Summary:
As pointed out by Vladislav in issue 217, if our RTDyld-based
linker fails to locate a symbol, it will crash with segfault. Fix that.
(cherry picked from FBD32481543)
Summary:
Currently there are two issues rendering the use of bughunter/BOLT on a binary
with a large number of functions (100k) impossible:
1) `selectFunctionsToProcess` has O(binary_fn * force_fn) run-time, which is up
to quadratic with the number of functions in the binary.
2) It unnecessarily treats supplied function names as regexes.
This diff proposes the following changes to address the issue:
1. Add two options that treat function names as is, not as regexes, matching
bughunter usage model: `-funcs-no-regex`/`-funcs-file-no-regex`.
These options are complementary to `-funcs`/`-funcs-file` and `-skip-funcs`/
`-skip-funcs-file`. `funcs` takes precedence over `funcs-no-regex`.
2. Use string set to speed up function eligibility checking with
`-funcs-file-no-regex` to O(binary_fn * log force_fn).
(cherry picked from FBD28917225)
Summary:
The push and pop instructions might have wrong reorder due to this
error. Thanks rafaelauler for the provided test case.
Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei
(cherry picked from FBD32478348)
Summary:
We were not tracking -DBUILD_SHARED_LIBS=ON and we introduced
some commits that break that by not specifying the correct dependencies.
Fix that.
(cherry picked from FBD32453377)
Summary: In some cases __open() is returning 0 for me. The open
syscall will return a negative number (-1) on error so 0 should be
valid.
This happens when one compiles a BOLT instrumented executable of
pyston (python implementation) and afterwards pip installs a package
which needs to be compiled and sets CFLAGS=-pipe. I could not reduce
it down to a small testcase but I guess it one can trigger when
manually closing std{in, out, err}. Everything seems to work
normally when disabling the assert for 0 in getBinaryPath() - I
decided to also modify the second case in readDescriptions() even
though I did not run into that one yet.
(cherry picked from FBD32409548)
Summary:
Make BOLT build in VisualStudio compiler and run without
crashing on a simple test. Other tests are not running.
(cherry picked from FBD32378736)
Summary:
Moved the FDATA printing under the condition of non-empty profile data.
The change reduces the assembly dumps.
(cherry picked from FBD32262675)
Summary:
Import the test. The assembly input has three functions with associated fdata.
The old link_fdata.sh script only replaces the symbol names with symbol values,
whereas fdata format expects to have symbol offsets against the anchor symbol.
Introduce the link_fdata.py script which is able to parse the input and produce
either an offset or an absolute symbol value.
(cherry picked from FBD32256351)
Summary:
The majority of tests in LLVM projects are using - instead of _ in the name,
i.e. `check-something.test` is preferred over `check_something.test`.
It makes sense for us to adopt the same naming scheme for our future tests and
to rename existing ones.
(cherry picked from FBD32185879)
Summary:
BOLT meta test using merge-fdata tool.
This tests BOLT instrumentation for a non-trivial binary, running instrumented
binary, and using the instrumentation profile for BOLT optimizations.
The results are verified between original, instrumented, and optimized binaries.
Additional tested features: boltdiff mode and merge-fdata for two profiles.
merge-fdata tool is linked with relocs on Linux to support this test.
(cherry picked from FBD32141812)
Summary:
Replace erroneous check for function eligibility from `Function.isIgnored()`
to `shouldOptimize(Function)`. This prevents non-simple functions from being
processed.
(cherry picked from FBD32301958)
Summary:
With LTO, it's possible for multiple DWARF compile units to share the
same abbreviation section set, i.e. to have the same abbrev_offset.
When units sharing the same abbrev set are located next to each other
and neither of them is being processed (i.e. contain processed
functions), it can trigger a bug in BOLT. When this happened,
the abbrev set is considered empty. Additionally, different units
may patch abbrev section differently.
The fix is to not rely on the next unit offset when detecting
abbreviation set boundaries and to delay writing abbrev section
until all units are processed.
(cherry picked from FBD31985046)
Summary:
This commit uses reviews.llvm.org/D6629 as a reference to optimize
X86::EFLAGS load/store in the instrumentation snippet by using lahf/sahf
instructions instead of pushf/popf.
(cherry picked from FBD31662303)
Summary:
Added new functionality of dumping simple functions into assembly.
This includes:
- function control flow (basic blocks, instructions),
- profile information as `FDATA` directives, to be consumed by link_fdata,
- data labels,
- CFI directives,
- symbols for callee functions,
- jump table symbols.
Envisioned usage:
1. Find a function that triggers BOLT crash (e.g. with `bughunter.sh`).
2. Generate reproducer asm source for that function (using `-funcs`).
3. Attach it to an issue.
4. Reduce and include as a test case.
Current limitations:
1. Emitted assembly won't match input file relocations.
2. No DWARF support.
3. Data is not emitted.
(cherry picked from FBD32746857)
Summary:
BinaryContext is available via BinaryFunction::getBinaryContext(),
hence there's no reason to pass both as arguments to a function.
In a similar fashion, BinaryBasicBlock has an access to BinaryFunction
via getFunction(). Eliminate unneeded arguments.
(cherry picked from FBD31921680)
Summary:
Change cmake config in BOLT to only support Linux. In other
platforms, we print a warning that we won't build BOLT. Change
configs to determine whether we will build BOLT runtime libs. This
only happens in x86 hosts. If true, we will build the runtime and
enable bolt-runtime tests. New tests that depend on the bolt_rt lib
needs to be marked REQUIRES:bolt-runtime. I updated the relevant
tests. Fix cmake to do not crash when building llvm with a target
that BOLT does not support.
(cherry picked from FBD31935760)
Summary:
Moves source files into separate components, and make explicit
component dependency on each other, so LLVM build system knows how to
build BOLT in BUILD_SHARED_LIBS=ON.
Please use the -c merge.renamelimit=230 git option when rebasing your
work on top of this change.
To achieve this, we create a new library to hold core IR files (most
classes beginning with Binary in their names), a new library to hold
Utils, some command line options shared across both RewriteInstance
and core IR files, a new library called Rewrite to hold most classes
concerned with running top-level functions coordinating the binary
rewriting process, and a new library called Profile to hold classes
dealing with profile reading and writing.
To remove the dependency from BinaryContext into X86-specific classes,
we do some refactoring on the BinaryContext constructor to receive a
reference to the specific backend directly from RewriteInstance. Then,
the dependency on X86 or AArch64-specific classes is transfered to the
Rewrite library. We can't have the Core library depend on targets
because targets depend on Core (which would create a cycle).
Files implementing the entry point of a tool are transferred to the
tools/ folder. All header files are transferred to the include/
folder. The src/ folder was renamed to lib/.
(cherry picked from FBD32746834)
Summary:
Increase the hard limit from 256 to 4096.
This fixes the 'Assertion failed: failed to open binary path' error I'm seeing.
(cherry picked from FBD31911946)
Summary:
This patch introduces remove-symtab option to be able to skip emitting
symtab section in the final binary.
Also this patch adds ".zdebug_*" (compressed debug section) in the list
of debug section names.
Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei
(cherry picked from FBD31738239)
Summary:
Some compilation units will contain only code that is left unmodified by
BOLT, e.g. there is no profile data available for any function from such
units as they are rarely or never executed.
To save processing time and memory, we disable building line info tables
for such units and write unmodified tables to the output file.
(cherry picked from FBD31599759)
Summary:
This patch temporarily disables instrumentation and higufy build not for
x86 platforms to be able to build llvm-bolt tool on aarch64.
Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei
(cherry picked from FBD31738306)
Summary:
Sync the file with storage device on data dump to stabilize
instrumentation testing
Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei
(cherry picked from FBD31738021)
Summary:
After the "Allocate memory for constant islands on-demand" patch there
are couple of problems found in constant islands handling:
1. When creating constant island dependency we need to check that we
already allocated IslandInfo for BF.
2. In ADRRelaxationPass we need to set constant island check under new
hasIslandsInfo condition.
3. In binaryemitter we need to replace hasConstantIsland with
hasIslandsInfo check since originally the BF might not have constant
island, but might have access to other's BF CI.
Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei
(cherry picked from FBD31737935)
Summary:
Refactored Loc and LocList writers to write out entries during finalization phase,
and hid some of the details in a class.
This simplifies things from impelementation details, and also will be needed for
DWARF5 where we need to know how many locLists entries there are there.
(cherry picked from FBD31563795)
Summary:
Add lit.local.cfg to X86 and AArch64 folders.
Fix host_arch in lit config for AArch64.
Fix AArch64 and X86 tests.
Elvina Yakubova,
Advanced Software Technology Lab, Huawei
(cherry picked from FBD31702068)
Summary:
This patch handles 2 problems with LongJmp pass:
1. The pass should be executed before FinalizeFunctions, since the pass
may add new entry points for the function, and the
BinaryFunction::addEntryPoint has an assert "CurrentState == State::CFG"
2. Replaced shortJmp implementation with position-independent code.
Currently we could handle PIC binaries with max +-4Gb offsets, the
longJmp uses absolute addreses and could could be used only in non-PIE
binaries.
Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei
(cherry picked from FBD31416925)
Summary:
In non-PIC binaries compiler could save absolute addresses in constant
isalnd which we should handle properly. This patch adds relocations
handling in constant islands.
Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei
(cherry picked from FBD31416848)
Summary:
Change sed separator to allow replacing symbols with slash in the name.
This is required for symbol names produced by BOLT which include
"/1" suffix.
(cherry picked from FBD31324540)
Summary:
This patch adds R_AARCH64_TSTBR14 and R_AARCH64_CONDBR19 relocations
support in order to handle condition branches, cbz/cnbz and tbz/tbnz
instructions correctly
Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei
(cherry picked from FBD31416734)
Summary:
The ELF::R_AARCH64_TLSDESC_LD64_LO12 and
ELF::R_AARCH64_TLSDESC_ADR_PAGE21 relocations might also be relaxed to
mov instructions, handle these cases
Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei
(cherry picked from FBD31353063)
Summary:
Use the new API introduced in https://reviews.llvm.org/D106624
to request LLVM do not process relocations for debug sections, since
BOLT processes final binaries that are already relocated.
(cherry picked from FBD31449206)
Summary:
When the compiler emits line table program, it emits EOS using the label
at the end of the containing code section. Since each compilation unit
has its own set of code sections it works as expected (* see the excerpt
from the standard below). However, in BOLT the code from many CUs is
combined into a common section, such as hot text or cold text.
As a result, the symbol at the end of the section may point way past the
code sequence for a given unit.
Since we can emit functions in any order, we conservatively emit
end-of-sequence at the end of every emitted function.
Fixes a problem while intermixing source code with disassembly in
binutils' objdump.
(*) DWARF v4 6.2.5.3:
"Every line number program sequence must end with a DW_LNE_end_sequence
instruction which creates a row whose address is that of the byte after
the last target machine instruction of the sequence."
(cherry picked from FBD31347870)
Amir Ayupov