This PR adds basic support for the MIPS R5900 CPU, the Emotion Engine
processor used in the PlayStation 2.
**LLVM changes:**
- Add r5900 CPU definition (with soft float support for now)
- Disable instructions not supported by r5900 (64-bit multiply/divide,
LL/SC atomics, COP3)
- Add r5900 specific short loop delay slot fix (hardware errata
workaround)
- Set ISA extension `AFL_EXT_5900` in ELF flags for proper ABI
identification
**Clang changes:**
- Add r5900 as a valid CPU target for `-mcpu=r5900`
- Add r5900 to CPU test coverage
If we compile a C code or IR file directly, the delay slot of BNE emit
by us won't be filled with a NOP.
We should fill it ourself, otherwise, the break instruction may be used
as the delay slot.
Fixes: #172965
In fact MipsAsmParser::expandDivRem is in a so bad status:
1. Div may not execute at all in most case
```
.set reorder
bnez $3, $tmp0
div $zero, $2, $3
break 7
$tmp0:
```
`.set reorder` may insert a nop after bnez, which will skip `div` if $3
is not zero.
2. `break 6` is wrong here.
Update all uses of variadic `.Cases` to use the initializer list
overload instead. I plan to mark variadic `.Cases` as deprecated in a
followup PR.
For more context, see https://github.com/llvm/llvm-project/pull/163117.
From clang version 4, mips append new instruction BeqImm and
BEQLImm, the second operand format of instruction is imm64:$imm.
1.When Mips process `beql $t0, ($t0), 1`, it think the second operand
was an imm, so match success. Then mips backend process expandBranchImm,
check the second operand `$t0` was not imm, reported asserts.
We can strengthen the second operand matching restrictions.
2.Similarly, when Mips process `beql $t0, (1), 1`, it think the second
was an imm. so match success. Then mips backend process expandBranchImm,
check the third operand `1` was not expression, reported asserts. Permit
the third operand of `beql` to be imm.
Fixes#151453.
Clang and other frontends generally need the LLVM data layout string in
order to generate LLVM IR modules for LLVM. MLIR clients often need it
as well, since MLIR users often lower to LLVM IR.
Before this change, the LLVM datalayout string was computed in the
LLVM${TGT}CodeGen library in the relevant TargetMachine subclass.
However, none of the logic for computing the data layout string requires
any details of code generation. Clients who want to avoid duplicating
this information were forced to link in LLVMCodeGen and all registered
targets, leading to bloated binaries. This happened in PR #145899,
which measurably increased binary size for some of our users.
By moving this information to the TargetParser library, we
can delete the duplicate datalayout strings in Clang, and retain the
ability to generate IR for unregistered targets.
This is intended to be a very mechanical LLVM-only change, but there is
an immediately obvious follow-up to clang, which will be prepared
separately.
The vast majority of data layouts are computable with two inputs: the
triple and the "ABI name". There is only one exception, NVPTX, which has
a cl::opt to enable short device pointers. I invented a "shortptr" ABI
name to pass this option through the target independent interface.
Everything else fits. Mips is a bit awkward because it uses a special
MipsABIInfo abstraction, which includes members with codegen-like
concepts like ABI physical registers that can't live in TargetParser. I
think the string logic of looking for "n32" "n64" etc is reasonable to
duplicate. We have plenty of other minor duplication to preserve
layering.
---------
Co-authored-by: Matt Arsenault <arsenm2@gmail.com>
Co-authored-by: Sergei Barannikov <barannikov88@gmail.com>
The unset state will be merged into the undefined state,
so isUnset should be avoided.
The code used by register equating uses the inaccurate condition.
```
.set r1, $4
```
For now just use isUndefined. GNU Assembler has a warning:
```
Warning: register value used as expression
```
* Fix `.reloc constant` to mean section_symbol+constant instead of
.+constant . The initial .reloc support from MIPS incorrectly
interpreted the offset.
* Delay the evaluation of the offset expression after
MCAssembler::layout, deleting a lot of code working with MCFragment.
* Delete many FIXME from https://reviews.llvm.org/D79625
* Some lld/ELF/Arch/LoongArch.cpp relaxation tests rely on .reloc .,
R_LARCH_ALIGN generating ALIGN relocations at specific location.
Sort the relocations.
Printing an expression is error-prone without a MCAsmInfo argument.
Remove the operator<< overload and replace callers with
MCAsmInfo::printExpr. Some callers are changed to MCExpr::print, with
the goal of eventually making it private.
so that subclasses can provide the appropriate MCAsmInfo to print
MCExpr objects.
At present, llvm/utils/TableGen/AsmMatcherEmitter.cpp constucts a
generic MCAsmInfo.
## 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
Many targets define MCTargetExpr subclasses just to encode an expression
with a relocation specifier. Create a generic MCSpecifierExpr to be
inherited instead. Migrate M68k and SPARC as examples.
We will replace the MCSymbolRefExpr member in MCValue with MCSymbol.
This change reduces dependence on MCSymbolRefExpr.
Create a MipsMCExpr::create overload that takes MCSymbol as an argument.
We use the order preferred by other targets.
Follow the X86 renaming.
> "Relocation modifier" suggests adjustments happen during the linker's relocation step rather than the assembler's expression evaluation.
> "Relocation specifier" is clear, aligns with Arm and IBM’s usage, and fits the assembler's role seamlessly.
In addition, rename MipsMCExpr::getKind, which confusingly shadows the base class getKind.
The module currently stores the target triple as a string. This means
that any code that wants to actually use the triple first has to
instantiate a Triple, which is somewhat expensive. The change in #121652
caused a moderate compile-time regression due to this. While it would be
easy enough to work around, I think that architecturally, it makes more
sense to store the parsed Triple in the module, so that it can always be
directly queried.
For this change, I've opted not to add any magic conversions between
std::string and Triple for backwards-compatibilty purses, and instead
write out needed Triple()s or str()s explicitly. This is because I think
a decent number of them should be changed to work on Triple as well, to
avoid unnecessary conversions back and forth.
The only interesting part in this patch is that the default triple is
Triple("") instead of Triple() to preserve existing behavior. The former
defaults to using the ELF object format instead of unknown object
format. We should fix that as well.
https://reviews.llvm.org/D23669 inappropriately added MIPS-specific
dtprel/tprel directives to MCStreamer. In addition,
llvm-mc -filetype=null parsing these directives will crash.
This patch moves these functions to MipsTargetStreamer and fixes
-filetype=null.
gprel32 and gprel64, called by AsmPrinter, are moved to
MCTargetStreamer.
A relocation expression might be used in an immediate operand or a
memory offset. https://reviews.llvm.org/D23110 , which intended to
generalize chained relocation operators (%hi(%neg(%gp_rel(x)))),
inappropriated introduced intrusive changes to the generic code. This
patch drops the intrusive changes and significantly simplifies the code.
The new style is similar to pre-D23110 but much cleaner.
Some weird expressions allowed by gas are not supported for simplicity,
e.g. "%lo foo", "(%lo(foo))", "%lo(foo)+1".
"(%lo(foo))", while previously parsed, is not used in practice.
"%lo(foo)+1" and "%lo(2*4)+foo" were previously parsed but would lead to
an error anyway as the expression is not relocatable
(`evaluateSymbolicAdd` does not fold the Add when RefKind are
different).
e.g.
`addiu $t2, $t3, .Lend-.Lstart-4`
used by libdragon/boot/boot_trampoline.S
To make this work, update a few places:
* AsmParser: When matching a isSImm/isUImm, consider an expression
that does not evaluate to an assemble-time constant an immediate.
* MCCodeEmitter: If this is an I-type instruction and the expression
does not evaluate to an assemble-time constant, append a
`fixup_Mips_AnyImm16`.
TODO: in MipsInstrInfo.td, more `Operand` should switch from the
default `getMachineOpValue` to `getImmOpValue` like RISCV.
* AsmBackend: If the expression does not evaluate to a constant
with assembler layout information, report "unknown relocation type"
like X86. If the result is not within [-32768,65535] (the bound gas
uses when parsing a constant integer for ADDIU)
Fix#126531
Pull Request: https://github.com/llvm/llvm-project/pull/127581
… instructions.
This is a fix I stumbled upon while working on something else. I decided
to break it out since it seems like a good "first issue" to submit. I
updated the comments in the "wrong error" test files to indicate that
the messages are no longer incorrect, but I left the names of the test
files alone. I was not sure what to do with those, so I would appreciate
thoughts or guidance.
…n MIPS
Modify:
Add a global variable 'CurForbiddenSlotAttr' to save current
instruction's forbidden slot and whether set reorder. This is the
judgment condition for whether to add nop. We would add a couple of
'.set noreorder' and '.set reorder' to wrap the current instruction and
the next instruction.
Then we can get previous instruction`s forbidden slot attribute and
whether set reorder by 'CurForbiddenSlotAttr'.
If previous instruction has forbidden slot and .set reorder is active
and current instruction is CTI. Then emit a NOP after it.
Fix https://github.com/llvm/llvm-project/issues/61045.
Because https://reviews.llvm.org/D158589 was 'Needs Review' state, not
ending, so we commit pull request again.
When parsing the `la` macro, we add a duplicate `$` prefix in
`getOrCreateSymbol`,
leading to `error: Undefined temporary symbol $$yy` for code like:
```
xx:
la $2,$yy
$yy:
nop
```
Remove the duplicate prefix.
In addition, recognize `.L`-prefixed symbols as local for O32.
See: #65020.
---------
Co-authored-by: Fangrui Song <i@maskray.me>
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.
This finishes the work of replacing OperandMatchResultTy with
ParseStatus, started in D154101.
As a drive-by change, rename some RegNo variables to just Reg
(a leftover from the days when RegNo had 'unsigned' type).
