Commit Graph

117 Commits

Author SHA1 Message Date
spupyrev 4609f60ebc [BOLT] Avoid pointless loop rotation
It seems the earlier implementation does not follow the description
in LoopRotationPass.h: It rotates loops even if they are already laid out
correctly. The diff adjusts the behaviour.

Given that the impact of LoopInversionPass is minor, this change won't
yield significant perf differences. Tested on clang-10: there seems to be a
0.1%-0.3% cpu win and a small reduction of branch misses.

**Before:**
BOLT-INFO: 120 Functions were reordered by LoopInversionPass

**After:**
BOLT-INFO: 79 Functions were reordered by LoopInversionPass

Reviewed By: yota9

Differential Revision: https://reviews.llvm.org/D121921
2022-03-22 12:42:42 -07:00
Vladislav Khmelevsky 5be5d0f56e [BOLT] LongJmp speedup refactoring
Run tentativeLayoutRelocMode twice only if UseOldText option was passed.
Refactor BF loop to break on condtition met.

Differential Revision: https://reviews.llvm.org/D121825
2022-03-18 16:16:47 +03:00
Amir Ayupov 42e8e00189 [BOLT][NFC] Use X86 mnemonic tables
Remove tables from X86MCPlusBuilder, make use of llvm::X86 mnemonic tables.

Reviewed By: rafauler

Differential Revision: https://reviews.llvm.org/D121573
2022-03-18 01:52:11 -07:00
Amir Ayupov dc1cf838a5 [BOLT] Strip redundant AdSize override prefix
Since LLVM MC now preserves redundant AdSize override prefix (0x67), remove it
in BOLT explicitly (-x86-strip-redundant-adsize, on by default).

Test Plan:
`bin/llvm-lit -a bolt/test/X86/addr32.s`

Reviewed By: rafauler

Differential Revision: https://reviews.llvm.org/D120975
2022-03-16 09:38:17 -07:00
Amir Ayupov 698127df51 [BOLT][NFC] Move isMOVSX64rm32 out of MCPlusBuilder
Reviewed By: rafauler

Differential Revision: https://reviews.llvm.org/D121669
2022-03-16 08:18:56 -07:00
Vladislav Khmelevsky 62a289d85c [BOLT] LongJmp: Fix hot text section alignment
The BinaryEmitter uses opts::AlignText value to align the hot text
section. Also check that the opts::AlignText is at least
equal opts::AlignFunctions for the same reason, as described in D121392.

Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei

Differential Revision: https://reviews.llvm.org/D121728
2022-03-16 15:57:46 +03:00
Maksim Panchenko 57f03db195 [BOLT][NFC] Remove unused function
Reviewed By: yota9

Differential Revision: https://reviews.llvm.org/D121729
2022-03-15 12:39:14 -07:00
Vladislav Khmelevsky 8ab69baad5 [BOLT] Set cold sections alignment explicitly
The cold text section alignment is set using the maximum alignment value
passed to the emitCodeAlignment. In order to calculate tentetive layout
right we will set the minimum alignment of such sections to the maximum
possible function alignment explicitly.

Differential Revision: https://reviews.llvm.org/D121392
2022-03-15 22:12:17 +03:00
Amir Ayupov 5790441c45 [BOLT][NFC] Use getShortOpcodeArith in X86MCPlusBuilder
Unify `llvm::X86::getRelaxedOpcodeArith` and `getShortArithOpcode` in
X86MCPlusBuilder.cpp.

Addresses https://lists.llvm.org/pipermail/llvm-dev/2022-January/154526.html

Reviewed By: rafauler

Differential Revision: https://reviews.llvm.org/D121404
2022-03-12 09:07:28 -08:00
Elvina Yakubova db65429db5 [BOLT] Divide RegularPageSize for X86 and AArch64 cases
For AArch64 in some cases/some distributions ld uses 64K alignment of LOAD segments by default.

Reviewed By: yota9, maksfb

Differential Revision: https://reviews.llvm.org/D119267
2022-03-10 23:09:50 +03:00
Vladislav Khmelevsky 04b87cf0e7 [BOLT] LongJmp: Use per-function alignment values
The per-function alignment values must be used in order to create
tentative layout.

Differential Revision: https://reviews.llvm.org/D121298
2022-03-10 19:48:48 +03:00
Amir Ayupov d1638cb0b5 [BOLT][NFC] Fix print-cfg data race
Addresses ThreadSanitizer warning

Reviewed By: rafauler

Differential Revision: https://reviews.llvm.org/D121337
2022-03-09 20:28:06 -08:00
Amir Ayupov d16bbc5340 [BOLT][NFC] Check errors from Obj.dynamicEntries
Addresses fuzzer crash

Reviewed By: rafauler

Differential Revision: https://reviews.llvm.org/D121336
2022-03-09 20:24:44 -08:00
Vladislav Khmelevsky 8bdbcfe7d8 [BOLT] Handle ifuncs trampolines for aarch64
The aarch64 uses the trampolines located in .iplt section, which
contains plt-like trampolines on the value stored in .got. In this case
we don't have JUMP_SLOT relocation, but we have a symbol that belongs to
ifunc trampoline, so use it and set set plt symbol for such functions.

Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei

Differential Revision: https://reviews.llvm.org/D120850
2022-03-09 01:38:19 +03:00
Amir Ayupov 1e016c3bd5 [BOLT][NFC] Handle "dynamic section sizes should match"
Address fuzzer crash on malformed input

Reviewed By: rafauler

Differential Revision: https://reviews.llvm.org/D121070
2022-03-08 13:03:05 -08:00
Amir Ayupov 687e4af1c0 [BOLT] CMOVConversion pass
Convert simple hammocks into cmov based on misprediction rate.

Test Plan:
- Assembly test: `cmov-conversion.s`
- Testing on a binary:
  # Bootstrap clang with `-x86-cmov-converter-force-all` and `-Wl,--emit-relocs`
  (Release build)
  # Collect perf.data:

    - `clang++ <opts> bolt/lib/Core/BinaryFunction.cpp -E > bf.cpp`
    - `perf record -e cycles:u -j any,u -- clang-15 bf.cpp -O2 -std=c++14 -c -o bf.o`
  # Optimize clang-15 with and w/o -cmov-conversion:
    - `llvm-bolt clang-15 -p perf.data -o clang-15.bolt`
    - `llvm-bolt clang-15 -p perf.data -cmov-conversion -o clang-15.bolt.cmovconv`
  # Run perf experiment:
    - test: `clang-15.bolt.cmovconv`,
    - control: `clang-15.bolt`,
    - workload (clang options): `bf.cpp -O2 -std=c++14 -c -o bf.o`
Results:
```
  task-clock [delta: -360.21 ± 356.75, delta(%): -1.7760 ± 1.7589, p-value: 0.047951, balance: -6]
  instructions  [delta: 44061118 ± 13246382, delta(%): 0.0690 ± 0.0207, p-value: 0.000001, balance: 50]
  icache-misses [delta: -5534468 ± 2779620, delta(%): -0.4331 ± 0.2175, p-value: 0.028014, balance: -28]
  branch-misses [delta: -1624270 ± 1113244, delta(%): -0.3456 ± 0.2368, p-value: 0.030300, balance: -22]
```

Reviewed By: rafauler

Differential Revision: https://reviews.llvm.org/D120177
2022-03-08 10:44:31 -08:00
Amir Ayupov ced5472e09 [BOLT][NFC] Check section contents before registering it
Address fuzzer crash on malformed input:
```
BOLT-ERROR: cannot get section contents for .dynsym: The end of the file was unexpectedly encountered.
```

Reviewed By: rafauler

Differential Revision: https://reviews.llvm.org/D121068
2022-03-08 09:13:01 -08:00
Maksim Panchenko fada230920 [BOLT][NFC] Return MCRegister::NoRegister from MCPlusBuilder::getNoRegister()
Reviewed By: yota9

Differential Revision: https://reviews.llvm.org/D120863
2022-03-03 13:25:13 -08:00
Vladislav Khmelevsky 00b6efc830 [BOLT] Enable PLT analysis for aarch64
This patch enables PLT analysis for aarch64. It is used by the static
relocations in order to provide final symbol address of PLT entry for some
instructions like ADRP.

Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei

Differential Revision: https://reviews.llvm.org/D118088
2022-03-02 22:14:48 +03:00
Amir Ayupov 08dcbed92f [BOLT] Fix X86MCPlusBuilder::replaceRegWithImm
Reassigning the operand didn't update the operand type which resulted in an
assertion (`Assertion `isReg() && "This is not a register operand!"' failed.`)
Reset the instruction instead.

Test Plan:
```
ninja check-bolt
...
PASS: BOLT-Unit :: Core/./CoreTests/X86/MCPlusBuilderTester.ReplaceRegWithImm/0 (90 of 136)
```

Reviewed By: rafauler

Differential Revision: https://reviews.llvm.org/D120263
2022-02-28 19:24:46 -08:00
Alexander Yermolovich a44fe31977 [BOLT][DWARF] Fix how DW_AT_high_pc [DW_FORM_udata] is handled
We were not handling correctly conversion from DW_AT_high_pc into DW_AT_ranges,
when size of DW_AT_high_pc is not 4/8 bytes.

Reviewed By: maksfb

Differential Revision: https://reviews.llvm.org/D120528
2022-02-25 10:32:05 -08:00
Maksim Panchenko 4101aa130a [BOLT] Support PC-relative relocations with addends
PC-relative memory operand could reference a different object from
the one located at the target address, e.g. when a negative offset
is used. Check relocations for the real referenced object.

Reviewed By: rafauler

Differential Revision: https://reviews.llvm.org/D120379
2022-02-23 22:54:42 -08:00
Amir Ayupov af6e66f44c [BOLT][NFC] Report errors from RewriteInstance `discoverStorage` and `run`
Further improve error handling in BOLT by reporting `RewriteInstance` errors in
a library and fuzzer-friendly way instead of exiting.

Follow-up to D119658

Reviewed By: rafauler

Differential Revision: https://reviews.llvm.org/D120224
2022-02-23 20:42:39 -08:00
Alexander Yermolovich 210bb04e23 [BOLT][DWARF] Remove patchLowHigh unused function.
Cleanup after removing caching mechanims for ranges/abbrevs.

Reviewed By: rafauler, yota9

Differential Revision: https://reviews.llvm.org/D120174
2022-02-22 13:28:15 -08:00
Amir Ayupov d44f99c748 [BOLT] Added fuzzer target (llvm-bolt-fuzzer)
This adds a target that would consume random binary as an
input ELF file.
TBD: add structured input support (ELF).

Build:
```
cmake /path/to/llvm-project/llvm -GNinja \
-DLLVM_TARGETS_TO_BUILD="X86;AArch64" \
-DCMAKE_BUILD_TYPE=Release \
-DLLVM_ENABLE_ASSERTIONS=1 \
-DCMAKE_C_COMPILER=<sanitizer-capable clang> \
-DCMAKE_CXX_COMPILER=<sanitizer-capable clang++> \
-DLLVM_ENABLE_PROJECTS="bolt"  \
-DLLVM_USE_SANITIZER=Address \
-DLLVM_USE_SANITIZE_COVERAGE=On
ninja llvm-bolt-fuzzer
```

Test Plan: ninja llvm-bolt-fuzzer

Reviewed By: maksfb

Differential Revision: https://reviews.llvm.org/D120016
2022-02-20 17:24:16 -08:00
Amir Ayupov 36ada32727 [BOLT][NFC] Fix data race in ShrinkWrapping stats
Fix data race reported by ThreadSanitizer in clang.test:
```
ThreadSanitizer: data race /data/llvm-project/bolt/lib/Passes/ShrinkWrapping.cpp:1359:28
in llvm::bolt::ShrinkWrapping::moveSaveRestores()
```

The issue is with incrementing global counters from multiple threads.

Reviewed By: yota9

Differential Revision: https://reviews.llvm.org/D120218
2022-02-20 17:21:58 -08:00
Amir Ayupov 32d2473a5d [BOLT][NFC] Report errors from createBinaryContext and RewriteInstance ctor
Refactor createBinaryContext and RewriteInstance/MachORewriteInstance
constructors to report an error in a library and fuzzer-friendly way instead of
returning a nullptr or exiting.

Reviewed By: rafauler

Differential Revision: https://reviews.llvm.org/D119658
2022-02-17 00:50:52 -08:00
Vladislav Khmelevsky 729d29e167 [BOLT] Update dynamic relocations from section relocations
This patch changes patchELFAllocatableRelaSections from going through
old relocations sections and update the relocation offsets to emitting
the relocations stored in binary sections. This is needed in case we
would like to remove and add dynamic relocations during BOLT work and it
is used by golang support pass. Note: Currently we emit relocations in
the old sections, so the total number of them should be equal or less
of old number.

Testing: No special tests are neeeded, since this patch does not fix
anything or add new functionality (it only prepares to add). Every
PIC-compiled test binary will use this code and thus become a test.
But just in case the aarch64 dynamic relocations tests were added.

Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei

Reviewed By: maksfb

Differential Revision: https://reviews.llvm.org/D117612
2022-02-16 18:40:54 +03:00
Shao-Ce SUN 2aed07e96c [NFC][MC] remove unused argument `MCRegisterInfo` in `MCCodeEmitter`
Reviewed By: skan

Differential Revision: https://reviews.llvm.org/D119846
2022-02-16 13:10:09 +08:00
Shao-Ce SUN 9cc49c1951 Revert "[NFC][MC] remove unused argument `MCRegisterInfo` in `MCCodeEmitter`"
This reverts commit fe25c06cc5.
2022-02-16 11:57:49 +08:00
Shao-Ce SUN fe25c06cc5 [NFC][MC] remove unused argument `MCRegisterInfo` in `MCCodeEmitter`
For ten years, it seems that `MCRegisterInfo` is not used by any target.

Reviewed By: skan

Differential Revision: https://reviews.llvm.org/D119846
2022-02-16 11:47:17 +08:00
Alexander Yermolovich bd1ebe9d04 [BOLT][DWARF] Add ability to insert new entries in to DIE
Added ability to append new entries to DIE. This is useful to standadize DWARF4
Split Dwarf, and simplify implementation of DWARF5.
Multiple DIEs can share an abbrev. So currently limitation is that only unique
Attributes can be added.

Reviewed By: maksfb

Differential Revision: https://reviews.llvm.org/D119577
2022-02-15 18:07:19 -08:00
serge-sans-paille 290e482342 Cleanup LLVMDWARFDebugInfo
As usual with that header cleanup series, some implicit dependencies now need to
be explicit:

llvm/DebugInfo/DWARF/DWARFContext.h no longer includes:
- "llvm/DebugInfo/DWARF/DWARFAcceleratorTable.h"
- "llvm/DebugInfo/DWARF/DWARFCompileUnit.h"
- "llvm/DebugInfo/DWARF/DWARFDebugAbbrev.h"
- "llvm/DebugInfo/DWARF/DWARFDebugAranges.h"
- "llvm/DebugInfo/DWARF/DWARFDebugFrame.h"
- "llvm/DebugInfo/DWARF/DWARFDebugLoc.h"
- "llvm/DebugInfo/DWARF/DWARFDebugMacro.h"
- "llvm/DebugInfo/DWARF/DWARFGdbIndex.h"
- "llvm/DebugInfo/DWARF/DWARFSection.h"
- "llvm/DebugInfo/DWARF/DWARFTypeUnit.h"
- "llvm/DebugInfo/DWARF/DWARFUnitIndex.h"

Plus llvm/Support/Errc.h not included by a bunch of llvm/DebugInfo/DWARF/DWARF*.h files

Preprocessed lines to build llvm on my setup:
after: 1065629059
before: 1066621848

Which is a great diff!

Discourse thread: https://discourse.llvm.org/t/include-what-you-use-include-cleanup
Differential Revision: https://reviews.llvm.org/D119723
2022-02-15 09:16:03 +01:00
Maksim Panchenko 5a343994c3 [BOLT] Make order of jump table successors deterministic
When a jump table is recovered in postProcessIndirectBranches(),
successors for the containing basic block are added in random order.
Make the order deterministic.

Reviewed By: yota9

Differential Revision: https://reviews.llvm.org/D119672
2022-02-14 10:37:20 -08:00
Maksim Panchenko 641e92d46b [BOLT] Skip warning message if no functions were ignored
Reviewed By: yota9, Amir

Differential Revision: https://reviews.llvm.org/D119673
2022-02-14 10:31:43 -08:00
serge-sans-paille 57f7c7d90e Add missing MC includes in bolt/
Changes needed after ef736a1c39 that removes some implicit
dependencies from MrCV headers.
2022-02-09 08:28:34 -05:00
Alexander Yermolovich 0d9921daad [BOLT][DWARF] Remove caching of ranges/abbrevs
Removing caching of ranges/abbrevs to simplify the code.
Before we were doing it to get around a gdb limitation.
FBD34015613

Reviewed By: Amir, maksfb

Differential Revision: https://reviews.llvm.org/D119276
2022-02-08 16:37:40 -08:00
Vladislav Khmelevsky 19fb5a210d [BOLT] Add aarch64 support for peephole passes
Enable peephole optimizations for aarch64.
Also small code refactoring - add PeepholeOpts under Peepholes class.

Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei

Differential Revision: https://reviews.llvm.org/D118732
2022-02-08 03:04:40 +03:00
Vladislav Khmelevsky 5c2ae5f454 [BOLT] Refactor heatmap to be standalone tool
Separate heatmap from bolt and build it as standalone tool.

Reviewed By: maksfb

Differential Revision: https://reviews.llvm.org/D118946
2022-02-07 22:00:44 +03:00
Amir Ayupov 194b164eb5 [BOLT][NFC] Fix compiler warnings
Summary:
- variable 'TotalSize' set but not used
- variable 'TotalCallsTopN' set but not used
- use of bitwise '|' with boolean operands

Reviewed By: maksfb

FBD33911129
2022-02-04 15:57:33 -08:00
Amir Ayupov 167b623a6a [BOLT][NFC] Use isInt<> instead of range checks
Summary: Reuse LLVM isInt check

Reviewed By: maksfb

FBD33945182
2022-02-02 20:32:05 -08:00
Alexander Yermolovich 9f3f9d19c7 [BOLT][DWARF] Handle shared abbrev section
We can have a scenario where multiple CUs share an abbrev table.
We modify or don't modify one CU, which leads to other CUs having invalid abbrev section.
Example that caused it.
All of CUs shared the same abbrev table. First CU just had compile_unit and sub_program.
It was not modified. Next CU had DW_TAG_lexical_block with
DW_AT_low_pc/DW_AT_high_pc converted to DW_AT_low_pc/DW_AT_ranges.
We used unmodified abbrev section for first and subsequent CUs.
So when parsing subsequent CUs debug info was corrupted.

In this patch we will now duplicate all sections that are modified and are different.
This also means that if .debug_types is present and it shares Abbrev table, and
they usually are, we now can have two Abbrev tables. One for CU that was modified,
and unmodified one for TU.

Reviewed By: maksfb

Differential Revision: https://reviews.llvm.org/D118517
2022-01-31 11:10:23 -08:00
Vladislav Khmelevsky e900f0584e [BOLT] Fix AARCH64 registers aliasing
The aarch64 platform has special registers like X0_X1_X2_X3_X4_X5_X6_X7.
Using the downwards propagation this register will become a super
register for all X0..X7 and its super registers which is not right. This
patch replaces the downwards propagation with caching all the aliases using MCRegAliasIterator.

Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei

Reviewed By: maksfb

Differential Revision: https://reviews.llvm.org/D117394
2022-01-28 01:24:35 +03:00
Alexander Yermolovich 612f0f4568 [BOLT][DWARF] Fix gdb index section
Since we now re-write .debug_info the DWARF CU Offsets can change.
Just like for .debug_aranges the GDB Index will need to be updated.

Reviewed By: Amir, maksfb

Differential Revision: https://reviews.llvm.org/D118273
2022-01-27 12:07:58 -08:00
Vladislav Khmelevsky 20e9d4caf0 [BOLT] Prepare BOLT for unit-testing
This patch adds unit testing support for BOLT. In order to do this we will need at least do this changes on the code level:
* Make createMCPlusBuilder accessible externally
* Remove positional InputFilename argument to bolt utlity sources
And prepare the cmake and lit for the new tests.

Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei

Reviewed By: maksfb, Amir

Differential Revision: https://reviews.llvm.org/D118271
2022-01-27 00:22:13 +03:00
Amir Ayupov f8c7fb499b [BOLT][NFC] Reduce includes with include-what-you-use
Summary: Removed redundant includes with IWYU

Test Plan: ninja bolt

Reviewers: maksfb

FBD32043568
2022-01-21 12:05:47 -08:00
Amir Ayupov 5a654b0113 [BOLT] Make ICP target selection (more) deterministic
Summary: Break ties by selecting targets with lower addresses.

Reviewers: maksfb

FBD33677001
2022-01-21 12:03:43 -08:00
Amir Ayupov f18fcdabda [BOLT][NFC] Expand auto types pt.2
Summary: Expand autos where it may lead to differences in the BOLT binary.

Test Plan: NFC

Reviewers: maksfb

Reviewed By: maks

FBD27673231
2022-01-21 12:02:57 -08:00
Vladislav Khmelevsky bb8e7ebaad [BOLT] Remove unreachable uncond branch after return
This patch fixes the removal of unreachable uncondtional branch located
after return instruction.

Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei

Reviewed By: Amir

Differential Revision: https://reviews.llvm.org/D117677
2022-01-19 22:06:26 +03:00
Amir Ayupov a9cd49d50e [BOLT][NFC] Move Offset annotation to Group 1
Summary:
Move the annotation to avoid dynamic memory allocations.
Improves the CPU time of instrumenting a large binary by 1% (+-0.8%, p-value 0.01)

Test Plan: NFC

Reviewers: maksfb

FBD30091656
2022-01-18 13:24:50 -08:00