When processing profile data for shared object or PIE, perf2bolt needs
to calculate base address of the binary based on the map info reported
by the perf tool. When the mapping data provided is for the second
(or any other than the first) segment and the segment's file offset
does not match its memory offset, perf2bolt uses wrong assumption
about the binary base address.
Add a function to calculate binary base address using the reported
memory mapping and use the returned base for further address
adjustments.
Reviewed By: yota9
Differential Revision: https://reviews.llvm.org/D123755
The ld might relax ADRP+ADD or ADRP+LDR sequences to the ADR+NOP, add
the new case to the skipRelocation for aarch64.
Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei
Differential Revision: https://reviews.llvm.org/D123334
Align with an upstream change D120305 to make PIE the default on linux-gnu.
Add `-no-pie` to tests that require it.
Reviewed By: maksfb, yota9
Differential Revision: https://reviews.llvm.org/D123329
BOLT expects PC-relative relocations in data sections to reference code
and the relocated data to form a jump table. However, there are cases
where PC-relative addressing is used for data-to-data references
(e.g. clang-15 can generate such code). BOLT should recognize and ignore
such relocations. Otherwise, they will be considered relocations not
claimed by any jump table and cause a failure in the strict mode.
Reviewed By: yota9, Amir
Differential Revision: https://reviews.llvm.org/D123650
tls-lld test might be broken since compiler might optimize plt function
call and use address directly from got table. The test is removed since
plt-gnu-ld checks the same functionality + versioning symbol matching,
no need to keep both of the tests.
The toolchain might optimize relocations in runtime-relocs test, replace
the test compilation with yaml files.
Differential Revision: https://reviews.llvm.org/D123332
Merging multiple legacy profiles (produced by instrumentation BOLT) can
easily reach GiBs. Let merge-fdata compact the profiles during merge to
significantly reduce space usage.
Differential Revision: https://reviews.llvm.org/D123513
Returning `std::array<uint8_t, N>` is better ergonomics for the hashing functions usage, instead of a `StringRef`:
* When returning `StringRef`, client code is "jumping through hoops" to do string manipulations instead of dealing with fixed array of bytes directly, which is more natural
* Returning `std::array<uint8_t, N>` avoids the need for the hasher classes to keep a field just for the purpose of wrapping it and returning it as a `StringRef`
As part of this patch also:
* Introduce `TruncatedBLAKE3` which is useful for using BLAKE3 as the hasher type for `HashBuilder` with non-default hash sizes.
* Make `MD5Result` inherit from `std::array<uint8_t, 16>` which improves & simplifies its API.
Differential Revision: https://reviews.llvm.org/D123100
Add !isTailCall in isUnconditionalBranch check in order to sync the x86
and aarch64 and fix the fixDoubleJumps pass on aarch64.
Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei
Differential Revision: https://reviews.llvm.org/D122929
The bfd linker adds the symbol versioning string to the symbol name in symtab.
Skip the versioning part in order to find the registered PLT function.
Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei
Differential Revision: https://reviews.llvm.org/D122039
Check for supported target architecture instead of the host arch when
deciding to execute non-runtime tests.
Reviewed By: Amir
Differential Revision: https://reviews.llvm.org/D122498
Read static relocs on the same address, as dynamic in order to update
constant island data address properly.
Differential Revision: https://reviews.llvm.org/D122100
Check that the function will be emitted in the final binary. Preserving
old function address is needed in case it is PLT trampiline, that is
currently not moved by the BOLT.
Differential Revision: https://reviews.llvm.org/D122098
BOLT treats aarch64 objects located in text as empty functions with
contant islands. Emit them with at least 8-byte alignment to the new
text section.
Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei
Differential Revision: https://reviews.llvm.org/D122097
AArch64 requires CI to be aligned to 8 bytes due to access instructions
restrictions. E.g. the ldr with imm, where imm must be aligned to 8 bytes.
Differential Revision: https://reviews.llvm.org/D122065
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
Run tentativeLayoutRelocMode twice only if UseOldText option was passed.
Refactor BF loop to break on condtition met.
Differential Revision: https://reviews.llvm.org/D121825
Remove tables from X86MCPlusBuilder, make use of llvm::X86 mnemonic tables.
Reviewed By: rafauler
Differential Revision: https://reviews.llvm.org/D121573
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
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
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
This clarifies that this is an LLVM specific variable and avoids
potential conflicts with other projects.
Differential Revision: https://reviews.llvm.org/D119918
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
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
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
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