Global data is emitted into parts, which are modelled as a MCSection. A
label (symbol of type LD) is not allowed in a part, which requires
special handling. The approach is to not emit the label at all, and
using the part symbol in relocations.
Add support for writing relocations. Since the symbol numbering is only
available after the symbols are written, the relocations are collected
in a vector. At write time, the relocations are converted using the
symbols ids, compressed and written out. A relocation data record is
limited to 32K-1 bytes, which requires making sure that larger
relocation data is written into multiple records.
Reflecting the [Coding
Standards](https://llvm.org/docs/CodingStandards.html), the following
changes were made to reflect this guideline.
```
Variable names should be nouns (as they represent state). The name should be camel case, and start with an upper-case letter (e.g. Leader or Boats).
```
The first letter in the variable names are changed to upper-case and
reflect being camel case.
Extract error reporting code emitted by CodeEmitterGen into
MCCodeEmitter static members functions.
Additionally, remove unused ErrorHandling.h header from several files.
The object file format specific derived classes are used in context
where the type is statically known. We don't use isa/dyn_cast and we
want to eliminate MCSymbol::Kind in the base class.
`Data` now references the first byte of the fixup offset within the current fragment.
MCAssembler::layout asserts that the fixup offset is within either the
fixed-size content or the optional variable-size tail, as this is the
most the generic code can validate without knowing the target-specific
fixup size.
Many backends applyFixup assert
```
assert(Offset + Size <= F.getSize() && "Invalid fixup offset!");
```
This refactoring allows a subsequent change to move the fixed-size
content outside of MCSection::ContentStorage, fixing the
-fsanitize=pointer-overflow issue of #150846
Pull Request: https://github.com/llvm/llvm-project/pull/151724
to facilitate replacing `MutableArrayRef<char> Data` (fragment content)
with the relocated location. This is necessary to fix the
pointer-overflow sanitizer issue and reland #150846
This removes the only virtual function of MCSection.
NVPTXTargetStreamer::changeSection uses the MCSectionELF print method.
Change it to just print the section name.
* Rename the vague `Value` to `Fill`.
* FillLen is at most 8. Making the field smaller to facilitate encoding
MCAlignFragment as a MCFragment union member.
* Replace an unreachable report_fatal_error with assert.
Follow-up to #141333. Relocation generation called both addReloc and
applyFixup, with the default addReloc invoking shouldForceRelocation,
resulting in three virtual calls. This approach was also inflexible, as
targets needing additional data required extending
`shouldForceRelocation` (see #73721, resolved by #141311).
This change integrates relocation handling into applyFixup, eliminating
two virtual calls. The prior default addReloc is renamed to
maybeAddReloc. Targets overriding addReloc now call their customized
addReloc implementation.
A HLASM source file must end with the END instruction. It is implemented
by adding a new function to the target streamer. This change also turns
SystemZHLASMSAsmString.h into a proper header file, and only uses the
SystemZTargetHLASMStreamer when HLASM output is generated.
MCExpr::print has an optional MCAsmInfo argument, which is error-prone
when omitted. MCExpr::print and the convenience helper operator<< are
discouraged to use. Switch to MCAsmInfo::printExpr instead. Use the
target-specific MCAsmInfo if available.
We introduced VariantKinds after MCSymbolRefExpr::VariantKind and then
deprecated the VariantKind naming in favor of AtSpecifier (#133214).
Rename the function and type to use the recommended convention.
## Purpose
This patch is one in a series of code-mods that annotate LLVM’s public
interface for export. This patch annotates the `llvm/Target` 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).
A sub-set 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 bulk of this change is manual additions of `LLVM_ABI` to
`LLVMInitializeX` functions defined in .cpp files under llvm/lib/Target.
Adding `LLVM_ABI` to the function implementation is required here
because they do not `#include "llvm/Support/TargetSelect.h"`, which
contains the declarations for this functions and was already updated
with `LLVM_ABI` in a previous patch. I considered patching these files
with `#include "llvm/Support/TargetSelect.h"` instead, but since
TargetSelect.h is a large file with a bunch of preprocessor x-macro
stuff in it I was concerned it would unnecessarily impact compile times.
In addition, a number of unit tests under llvm/unittests/Target required
additional dependencies to make them build correctly against the LLVM
DLL on Windows using MSVC.
## 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
z/OS creates SystemZMCExpr objects (https://reviews.llvm.org/D153788)
while ELF doesn't. Define the SystemZMCAsmInfoGOFF hooks
instead of the legacy MCSpecifierExpr:: hooks.
Introduce MCAsmInfo::UsesSetToEquateSymbol to control the preferred
syntax for symbol equating. We now favor the more readable and common
`symbol = expression` syntax over `.set`. This aligns with pre- https://reviews.llvm.org/D44256 behavior.
On Apple platforms, this resolves a clang -S vs -c behavior difference (resolves#104623).
For targets whose = support is unconfirmed, UsesSetToEquateSymbol is set to false.
This also minimizes test updates.
Pull Request: https://github.com/llvm/llvm-project/pull/142289
Replace MCSymbol argument with MCValue::AddSym. The minor difference in
.weakref handling is negligible, as our implementation may not fully
align with GAS, and .weakref is not used in practice.
Remove the MCSubtargetInfo argument from applyFixup, introduced in
https://reviews.llvm.org/D45962 , as it's only required by ARM. Instead,
add const MCFragment & so that ARMAsmBackend can retrieve
MCSubtargetInfo via a static member function.
Additionally, remove the MCAssembler argument, which is also only
required by ARM.
Additionally, make applyReloc non-const. Its arguments now fully cover
addReloc's functionality.
This reverts the code change in commit
e87f33d9ce785668223c3bcc4e06956985cccda1 (#73721) but keeps its test.
There have been many changes to lib/MC and AsmBackend.cpp files, so this
is not a pure revert.
#73721, a workaround to generate necessary relocations in mixed
non-relax/relax code,
is no longer necessary after #140692 fixed the root issue (whether two
locations are separated by a fragment with indeterminate size due to
linker relaxation).
For IsPCRel fixups, we had the `A->getKind() != MCSymbolRefExpr::VK_None`
condition to force relocations. The condition has then been changed to
`Target.getSpecifier()` (086af836889436baffc71c743c7c8259bad8ed60).
38c3ad36be1facbe6db2dede7e93c0f12fb4e1dc updated
shouldForceRelocation to test `Target.getSpecifier`.
It is not a good fit as many targets with %lo/%hi style specifiers
(SPARC, MIPS, PowerPC, RISC-V) do not force relocations for these
specifiers.
Revert the Target.getSpecifier implementation
(38c3ad36be1facbe6db2dede7e93c0f12fb4e1dc) and update
targets that need it (SystemZAsmBackend/X86AsmBackend) instead.
Targets need customization might define addReloc instead.
Note: The X86AsmBackend implementation is too conservative.
GNU Assembler doesn't emit a relocation for `call local@plt; local`
a3d39316764726ed9fd939550c7781199b1eb77e added missing coverage
for GOT/PLT related relocations.
As noticed in https://github.com/llvm/llvm-project/pull/140471, the
SystemZ target currently implements disassembly of PC-relative target
addresses differently from other back-ends. This patch brings SystemZ in
line with other targets.
Specifically, this patch changes the relevant MCInst instructions to
carry a PC-relative displacement instead of an absolute target address
in their immediate fields. When printing the instruction, this
displacement will either be shown as is (e.g. for llvm-mc), or else
translated into an absolute address at print time (e.g. for
llvm-objdump).
The existing llvm-mc based tests using PC-relative operands no longer
work and have to be rewritten, but printing displacements makes those
tests easier to maintain anyway.
Revert the Target.getSpecifier implementation
(38c3ad36be1facbe6db2dede7e93c0f12fb4e1dc) and update SystemZAsmBackend
instead.
Many targets with %lo/%hi style specifiers (SPARC, MIPS, PowerPC,
RISC-V) do not force relocations for these specifiers.
Additionally, with the introduction of the addReloc hook,
shouldForceRelocation is not that necessary and should probably be
phased out.
The `.machine push` and `.machine pop` directives were missing from the
SystemZ Backend Asm Parser. This PR adds them, and expands the
corresponding test to test proper operation.
Internally, this is modeled as a simple stack implemented on a
`SmallVector<StringRef>`.
We will increase the use of raw relocation types and eliminate fixup
kinds that correspond to relocation types. The getFixupKindInfo
functions will return an rvalue instead. Let's update the return type
from a const reference to a value type.
Add two helper functions to simplify checks for relocation types,
replacing direct comparisons with FirstRelocationKind and
FirstLiteralRelocationKind. Note: Some targets haven't utilized
isRelocation yet.
Also, update RelaxFixupKind to use 0 as the sentinel value.
- _Float16 is now accepted by Clang.
- The half IR type is fully handled by the backend.
- These values are passed in FP registers and converted to/from float around
each operation.
- Compiler-rt conversion functions are now built for s390x including the missing
extendhfdf2 which was added.
Fixes#50374
Move `Fixup.getKind() >= FirstLiteralRelocationKind` from target hooks
to ELFObjectWriter::recordRelocation.
Currently, getRelocType cannot be skipped for LoongArch due to #135519
... to clarify ownership, aligning with other parameters. Using
`std::unique_ptr` encourages users to manage `createMCInstPrinter` with
a unique_ptr instead of a raw pointer, reducing the risk of memory
leaks.
* llvm-mc: fix a leak and update llvm/test/tools/llvm-mc/disassembler-options.test
* #121078 copied the llvm-mc code to CodeGenTargetMachineImpl and made
the same mistake. Fixed by 2b8cc651dca0c000ee18ec79bd5de4826156c9d6
Using unique_ptr requires #include MCInstPrinter.h in a few translation
units.
* Delete a createAsmStreamer overload I deprecated in 2024
* SystemZMCTargetDesc.cpp: rename to `createSystemZAsmStreamer` to fix
an overload conflict.
Pull Request: https://github.com/llvm/llvm-project/pull/135128
Commit 52eb11f925ddeba4e1b3840fd636ee87387f3ada temporarily introduced
getSymSpecifier to prepare for "MCValue: Replace MCSymbolRefExpr members
with MCSymbol" (d5893fc2a7e1191afdb4940469ec9371a319b114). The
refactoring is now complete.
Commit 52eb11f925ddeba4e1b3840fd636ee87387f3ada temporarily introduced
getSymSpecifier to prepare for "MCValue: Replace MCSymbolRefExpr members
with MCSymbol" (d5893fc2a7e1191afdb4940469ec9371a319b114). The
refactoring is now complete.
