In C++17, static constexpr members are implicitly inline, so they no
longer require an out-of-line definition.
Identified with readability-redundant-declaration.
We have optimized the implementation of introducing the "matching and
inference" technique into Propeller. In this new implementation, we have
made every effort to avoid introducing new compilation parameters while
ensuring compatibility with Propeller's current usage. Instead of
creating a new profile format, we reused the existing one employed by
Propeller. This new implementation is fully compatible with Propeller's
current usage patterns and reduces the amount of code changes. For
detailed information, please refer to the following RFC:
https://discourse.llvm.org/t/rfc-adding-matching-and-inference-functionality-to-propeller/86238.
We plan to submit the relevant changes in several pull requests (PRs).
The current one is the first PR, which adds the basic block hash to the
SHT_LLVM_BB_ADDR_MAP section.
co-authors: lifengxiang1025 <lifengxiang@kuaishou.com>; zcfh
<wuminghui03@kuaishou.com>
Co-authored-by: lifengxiang1025 <lifengxiang@kuaishou.com>
Co-authored-by: zcfh <wuminghui03@kuaishou.com>
Co-authored-by: Rahman Lavaee <rahmanl@google.com>
This PR simply moves the callsite anchors from the beginning of
callsites to their end.
Emitting the end of callsites is more sensible as it allows breaking the
basic block into subblocks which end with control transfer instructions.
Recently, we have been looking at some optimizations targeting
individual calls. In particular, we plan to extend the address mapping
technique to map to individual callsites. For example, in this piece of
code for a basic blocks:
```
<BB>:
1200: lea 0x1(%rcx), %rdx
1204: callq foo
1209: cmpq 0x10, %rdx
120d: ja L1
```
We want to emit 0x9 as the call site offset for `callq foo` (the offset
from the block entry to right after the call), so that we know if a
sampled address is before the call or after.
This PR implements the decode/encode/emit capability. The Codegen change
will be implemented in a later PR.
gfx940 and gfx941 are no longer supported. This is one of a series of
PRs to remove them from the code base.
This PR removes all non-documentation occurrences of gfx940/gfx941 from
the llvm directory, and the remaining occurrences in clang.
Documentation changes will follow.
For SWDEV-512631
Alternative to #123137
With -DMACHINE=EM_NONE, machine specific
sections, like SHT_ARM_EXIDX, will fall to parse
and set `Type`.
This triggers msan on
```
yaml2obj llvm-project/llvm/test/tools/yaml2obj/ELF/mips-abi-flags.yaml -DMACHINE=EM_NONE
```
Size is required, so we don't know if it's in
uninitialized state after the previous error.
Triggers msan on llvm/test/tools/yaml2obj/ELF/custom-fill.yaml NOSIZE
test.
We have `Fill` Section with Pattern, but no size. Before the fix it
produced error:
```
YAML:169:5: error: missing required key 'Size'
- Type: Fill
^
YAML:169:5: error: "Size" can't be 0 when "Pattern" is not empty
- Type: Fill
```
The same applies to `MachOYAML::Section` fields `content` and `size`.
However `MachOYAML::Section` matches size first, so on error,
content is not set anyway. Added error checking just in case.
It will not be set if:
1. `(TypeStr.starts_with("SHT_") || isInteger(TypeStr)) == false`: here
we want go to switch default.
2. `IO.mapRequired("Type", Type);` fail parsing. It sets error
internally, so probably not important what happen next, so it's go to
the switch
This patch introduces support for the Hexagon V75 architecture. It
includes instruction formats, definitions, encodings, scheduling
classes, and builtins/intrinsics.
The ARM Guarded Control Stack extension (GCS) is similar to existing
shadow stack extensions for other architectures.
The core note will include which features of GCS are enabled, which have
been locked in their current state, and the stack pointer of the shadow
stack.
Note that 0x40f is NT_ARM_POE, FPMR is supported by LLDB and GCS will be
soon, POE is not at this time. So NT_ARM_POE will be added when that
work starts.
See
https://github.com/torvalds/linux/blob/master/include/uapi/linux/elf.h.
This patch introduces a new generic target, `gfx9-4-generic`. Since it doesn’t support FP8 and XF32-related instructions, the patch includes several code reorganizations to accommodate these changes.
This contains the fpmr register which was added in Armv9.5-a. This
register mainly contains controls for fp8 formats.
It was added to the Linux Kernel in
4035c22ef7.
CREL is a compact relocation format for the ELF object file format.
This patch adds integrated assembler support (using the RELA form)
available with `llvm-mc -filetype=obj -crel a.s -o a.o`.
A dependent patch will add `clang -c -Wa,--crel,--allow-experimental-crel`.
Also add llvm-readobj support (for both REL and RELA forms) to
facilitate testing the assembler. Additionally, yaml2obj gains support
for the RELA form to aid testing with llvm-readobj.
We temporarily assign the section type code 0x40000020 from the generic
range to `SHT_CREL`. We avoided using `SHT_LLVM_` or `SHT_GNU_` to
avoid code churn and maintain broader applicability for interested psABIs.
Similarly, `DT_CREL` is temporarily 0x40000026.
LLVM will change the code and break compatibility. This is not an issue
if all relocatable files using CREL are regenerated (aka no prebuilt
relocatable files).
Link: https://discourse.llvm.org/t/rfc-crel-a-compact-relocation-format-for-elf/77600
Pull Request: https://github.com/llvm/llvm-project/pull/91280
Defines a subset of attributes and emits them to a section called
.hexagon.attributes.
The current attributes recorded are the attributes needed by
llvm-objdump to automatically determine target features and eliminate
the need to manually pass features.
Linux kernel fs/binfmt_elf_fdpic.c supports FDPIC for MMU-less systems.
GCC/binutils/qemu support FDPIC ABI for ARM
(https://github.com/mickael-guene/fdpic_doc).
_ARM FDPIC Toolchain and ABI_ provides a summary.
This patch implements FDPIC relocations to the integrated assembler.
There are 6 static relocations and 2 dynamic relocations, with
R_ARM_FUNCDESC as both static and dynamic.
gas requires `--fdpic` to assemble data relocations like `.word f(FUNCDESC)`.
This patch adds `MCTargetOptions::FDPIC` and reports an error if FDPIC
is not set.
Pull Request: https://github.com/llvm/llvm-project/pull/82187
These generic targets include multiple GPUs and will, in the future,
provide a way to build once and run on multiple GPU, at the cost of less
optimization opportunities.
Note that this is just doing the compiler side of things, device libs an
runtimes/loader/etc. don't know about these targets yet, so none of them
actually work in practice right now. This is just the initial commit to
make LLVM aware of them.
This contains the documentation changes for both this change and #76954
as well.
Introduce Code Object V6 in Clang, LLD, Flang and LLVM. This is the same
as V5 except a new "generic version" flag can be present in EFLAGS. This
is related to new generic targets that'll be added in a follow-up patch.
It's also likely V6 will have new changes (possibly new metadata
entries) added later.
Docs change are part of the follow-up patch #76955
Today `-split-machine-functions` and `-fbasic-block-sections={all,list}`
cannot be combined with `-basic-block-sections=labels` (the labels
option will be ignored).
The inconsistency comes from the way basic block address map -- the
underlying mechanism for basic block labels -- encodes basic block
addresses
(https://lists.llvm.org/pipermail/llvm-dev/2020-July/143512.html).
Specifically, basic block offsets are computed relative to the function
begin symbol. This relies on functions being contiguous which is not the
case for MFS and basic block section binaries. This means Propeller
cannot use binary profiles collected from these binaries, which limits
the applicability of Propeller for iterative optimization.
To make the `SHT_LLVM_BB_ADDR_MAP` feature work with basic block section
binaries, we propose modifying the encoding of this section as follows.
First let us review the current encoding which emits the address of each
function and its number of basic blocks, followed by basic block entries
for each basic block.
| | |
|--|--|
| Address of the function | Function Address |
| Number of basic blocks in this function | NumBlocks |
| BB entry 1
| BB entry 2
| ...
| BB entry #NumBlocks
To make this work for basic block sections, we treat each basic block
section similar to a function, except that basic block sections of the
same function must be encapsulated in the same structure so we can map
all of them to their single function.
We modify the encoding to first emit the number of basic block sections
(BB ranges) in the function. Then we emit the address map of each basic
block section section as before: the base address of the section, its
number of blocks, and BB entries for its basic block. The first section
in the BB address map is always the function entry section.
| | |
|--|--|
| Number of sections for this function | NumBBRanges |
| Section 1 begin address | BaseAddress[1] |
| Number of basic blocks in section 1 | NumBlocks[1] |
| BB entries for Section 1
|..................|
| Section #NumBBRanges begin address | BaseAddress[NumBBRanges] |
| Number of basic blocks in section #NumBBRanges |
NumBlocks[NumBBRanges] |
| BB entries for Section #NumBBRanges
The encoding of basic block entries remains as before with the minor
change that each basic block offset is now computed relative to the
begin symbol of its containing BB section.
This patch adds a new boolean codegen option `-basic-block-address-map`.
Correspondingly, the front-end flag `-fbasic-block-address-map` and LLD
flag `--lto-basic-block-address-map` are introduced.
Analogously, we add a new TargetOption field `BBAddrMap`. This means BB
address maps are either generated for all functions in the compiling
unit, or for none (depending on `TargetOptions::BBAddrMap`).
This patch keeps the functionality of the old
`-fbasic-block-sections=labels` option but does not remove it. A
subsequent patch will remove the obsolete option.
We refactor the `BasicBlockSections` pass by separating the BB address
map and BB sections handing to their own functions (named
`handleBBAddrMap` and `handleBBSections`). `handleBBSections` renumbers
basic blocks and places them in their assigned sections.
`handleBBAddrMap` is invoked after `handleBBSections` (if requested) and
only renumbers the blocks.
- New tests added:
- Two tests basic-block-address-map-with-basic-block-sections.ll and
basic-block-address-map-with-mfs.ll to exercise the combination of
`-basic-block-address-map` with `-basic-block-sections=list` and
'-split-machine-functions`.
- A driver sanity test for the `-fbasic-block-address-map` option
(basic-block-address-map.c).
- An LLD test for testing the `--lto-basic-block-address-map` option.
This reuses the LLVM IR from `lld/test/ELF/lto/basic-block-sections.ll`.
- Renamed and modified the two existing codegen tests for basic block
address map (`basic-block-sections-labels-functions-sections.ll` and
`basic-block-sections-labels.ll`)
- Removed `SHT_LLVM_BB_ADDR_MAP_V0` tests. Full deprecation of
`SHT_LLVM_BB_ADDR_MAP_V0` and `SHT_LLVM_BB_ADDR_MAP` version less than 2
will happen in a separate PR in a few months.
Reviewed in PR (#71750). A part of [RFC - PGO Accuracy Metrics: Emitting and Evaluating Branch
and Block
Analysis](https://discourse.llvm.org/t/rfc-pgo-accuracy-metrics-emitting-and-evaluating-branch-and-block-analysis/73902).
This PR adds the PGOAnalysisMap data structure and implements encoding and
decoding through Object and ObjectYAML along with associated tests. When
emitted into the bb-addr-map section, each function is followed by the associated
pgo-analysis-map for that function. The emitting of each analysis in the map is
controlled by a bit in the bb-addr-map feature byte. All existing bb-addr-map
code can ignore the pgo-analysis-map if the caller does not request the data.
This patch replaces uses of StringRef::{starts,ends}with with
StringRef::{starts,ends}_with for consistency with
std::{string,string_view}::{starts,ends}_with in C++20.
I'm planning to deprecate and eventually remove
StringRef::{starts,ends}with.
