Simon Atanasyan [Wed, 17 Jul 2019 08:11:31 +0000 (08:11 +0000)]
[mips] Implement .cplocal directive
This directive forces to use the alternate register for context pointer.
For example, this code:
.cplocal $4
jal foo
expands to:
ld $25, %call16(foo)($4)
jalr $25
Simon Atanasyan [Wed, 17 Jul 2019 08:11:15 +0000 (08:11 +0000)]
[mips] Support the "o" inline asm constraint
As well as other LLVM targets we do not handle "offsettable"
memory addresses in any special way. In other words, the "o" constraint
is an exact equivalent of the "m" one. But some existing code require
the "o" constraint support.
It is possible that exit block has two predecessors and one of them is a latch
block while another is not.
Current algorithm is based on the assumption that all exits are dedicated
and therefore we can check only first predecessor of loop exit to find all unique
exits.
However if we do not consider latch block and it is first predecessor of some
exit then this exit will be found.
Regression test is added.
As a side effect of algorithm re-writing, the restriction that all exits are dedicated
is eliminated.
[TableGen] Generate offsets into a flat array for getOperandType
Rather than an array of std::initializer_list, generate a table of
offsets and a flat array of the operands for getOperandType. This is a
bit more efficient on platforms that don't manage to get the array of
inintializer_lists initialized at link time (I'm looking at you
macOS). It's also quite quite a bit faster to compile.
[WebAssembly] Compile all TLS on Emscripten as local-exec
Summary:
Currently, on Emscripten, dynamic linking is not supported with threads.
This means that if thread-local storage is used, it must be used in a
statically-linked executable. Hence, local-exec is the only possible model.
This diff compiles all TLS variables to use local-exec on Emscripten as a
temporary measure until dynamic linking is supported with threads.
The goal for this is to allow C++ types with constructors to be thread-local.
Currently, when `clang` compiles a `thread_local` variable with a constructor,
it generates `__tls_guard` variable:
@__tls_guard = internal thread_local global i8 0, align 1
As no TLS model is specified, this is treated as general-dynamic, which we do
not support (and cannot support without implementing dynamic linking support
with threads in Emscripten). As a result, any C++ constructor in `thread_local`
variables would not compile.
By compiling all `thread_local` as local-exec, `__tls_guard` will compile and
we can support C++ constructors with TLS without implementing dynamic linking
with threads.
[TableGen] Add "getOperandType" to get operand types from opcode/opidx
The InstrInfoEmitter outputs an enum called "OperandType" which gives
numerical IDs to each operand type. This patch makes use of this enum
to define a function called "getOperandType", which allows looking up
the type of an operand given its opcode and operand index.
Summary:
Thread local variables are placed inside a `.tdata` segment. Their symbols are
offsets from the start of the segment. The address of a thread local variable
is computed as `__tls_base` + the offset from the start of the segment.
`.tdata` segment is a passive segment and `memory.init` is used once per thread
to initialize the thread local storage.
`__tls_base` is a wasm global. Since each thread has its own wasm instance,
it is effectively thread local. Currently, `__tls_base` must be initialized
at thread startup, and so cannot be used with dynamic libraries.
`__tls_base` is to be initialized with a new linker-synthesized function,
`__wasm_init_tls`, which takes as an argument a block of memory to use as the
storage for thread locals. It then initializes the block of memory and sets
`__tls_base`. As `__wasm_init_tls` will handle the memory initialization,
the memory does not have to be zeroed.
To help allocating memory for thread-local storage, a new compiler intrinsic
is introduced: `__builtin_wasm_tls_size()`. This instrinsic function returns
the size of the thread-local storage for the current function.
The expected usage is to run something like the following upon thread startup:
This is part of what is requested by PR42023:
https://bugs.llvm.org/show_bug.cgi?id=42023
There's an extension needed for FP add, but exactly how we would specify
that using flags is not clear to me, so I left that as a TODO.
We're still missing patterns for partial reductions when the input vector
is 256-bit or 512-bit, but I think that's a failure of vector narrowing.
If we can reduce the widths, then this matching should work on those tests.
David Blaikie [Tue, 16 Jul 2019 21:15:19 +0000 (21:15 +0000)]
DWARF: Skip zero column for inline call sites
D64033 <https://reviews.llvm.org/D64033> added DW_AT_call_column for
inline sites. However, that change wasn't aware of "-gno-column-info".
To avoid adding column info when "-gno-column-info" is used, now
DW_AT_call_column is only added when we have non-zero column (when
"-gno-column-info" is used, column will be zero).
Matt Arsenault [Tue, 16 Jul 2019 20:15:30 +0000 (20:15 +0000)]
AMDGPU/GlobalISel: Select G_SHL
I think this manages to not break the DAG handling with the divergent
predicates because the stadalone divergent patterns end up with a
higher priority than the pattern on the instruction definition.
Philip Reames [Tue, 16 Jul 2019 18:23:49 +0000 (18:23 +0000)]
[IndVars] Speculative fix for an assertion failure seen in bots
I don't have an IR sample which is actually failing, but the issue described in the comment is theoretically possible, and should be guarded against even if there's a different root cause for the bot failures.
Matt Arsenault [Tue, 16 Jul 2019 18:05:29 +0000 (18:05 +0000)]
AMDGPU/GlobalISel: Select flat loads
Now that the patterns use the new PatFrag address space support, the
only blocker to importing most load patterns is the addressing mode
complex patterns.
Reimplement scheduling constraints for strict FP instructions in
ScheduleDAGInstrs::buildSchedGraph to allow for more relaxed
scheduling. Specifially, allow one strict FP instruction to
be scheduled across another, as long as it is not moved across
any global barrier.
[Remarks] Simplify and refactor the RemarkParser interface
Before, everything was based on some kind of type erased parser
implementation which container a lot of boilerplate code when multiple
formats were to be supported.
This simplifies it by:
* the remark now owns its arguments
* *always* returning an error from the implementation side
* working around the way the YAML parser reports errors: catch them through
callbacks and re-insert them in a proper llvm::Error
* add a CParser wrapper that is used when implementing the C API to
avoid cluttering the C++ API with useless state
* LLVMRemarkParserGetNext now returns an object that needs to be
released to avoid leaking resources
* add a new API to dispose of a remark entry: LLVMRemarkEntryDispose
Matt Arsenault [Tue, 16 Jul 2019 14:28:30 +0000 (14:28 +0000)]
AMDGPU/GlobalISel: Fix test failures in release build
Apparently the check for legal instructions during instruction
select does not happen without an asserts build, so these would
successfully select in release, and fail in debug.
Make s16 and/or/xor legal. These can just be selected directly
to the 32-bit operation, as is already done in SelectionDAG, so just
make them legal.
George Rimar [Tue, 16 Jul 2019 11:07:30 +0000 (11:07 +0000)]
[Object/llvm-readelf/llvm-readobj] - Improve error reporting when e_shstrndx is broken.
When e_shstrndx is broken, it is impossible to get a section name.
In this patch I improved the error message we show and
added tests for Object and for llvm-readelf/llvm-readobj
Message was changed in two places:
1) llvm-readelf/llvm-readobj previously used a code from Object/ELF.h,
now they have a modified version of it (it has less checks and allows
dumping broken things).
2) Code in Object/ELF.h is still used for generic cases.
[AArch64] Implement __jcvt intrinsic from Armv8.3-A
The jcvt intrinsic defined in ACLE [1] is available when ARM_FEATURE_JCVT is defined.
This change introduces the AArch64 intrinsic, wires it up to the instruction and a new clang builtin function.
The __ARM_FEATURE_JCVT macro is now defined when an Armv8.3-A or higher target is used.
I've implemented the target detection logic in Clang so that this feature is enabled for architectures from armv8.3-a onwards (so -march=armv8.4-a also enables this, for example).
Alex Bradbury [Tue, 16 Jul 2019 04:56:43 +0000 (04:56 +0000)]
[RISCV] Match GNU tools canonical JALR and add aliases
The canonical GNU form of JALR resembles a load/store instruction rather
than placing the immediate offset as a separate argument, so match this
behaviour. Also add parser-only aliases for the three-operand form, and
add other shorter aliases also emitted by GNU tools.
Differential Revision: https://reviews.llvm.org/D55277
Patch by James Clarke.
Alex Bradbury [Tue, 16 Jul 2019 04:40:25 +0000 (04:40 +0000)]
[RISCV] Avoid overflow when determining number of nops for code align
RISCVAsmBackend::shouldInsertExtraNopBytesForCodeAlign() assumed that the
align specified would be greater than or equal to the minimum nop length, but
that is not always the case - for example if a user specifies ".align 0" in
assembly.
Differential Revision: https://reviews.llvm.org/D63274
Patch by Edward Jones.
Alex Bradbury [Tue, 16 Jul 2019 04:37:19 +0000 (04:37 +0000)]
[RISCV] Fix a potential issue in shouldInsertFixupForCodeAlign()
The bool result of shouldInsertExtraNopBytesForCodeAlign() is not checked but
the returned nop count is unconditionally read even though it could be
uninitialized.
Differential Revision: https://reviews.llvm.org/D63285
Patch by Edward Jones.
Alex Bradbury [Tue, 16 Jul 2019 03:56:45 +0000 (03:56 +0000)]
[RISCV][NFC] Split PseudoCALL pattern out from instruction
Since PseudoCALL defines AsmString, it can be generated from assembly,
and so code-gen patterns should be defined separately to be consistent
with the style of the RISCV backend. Other pseudo-instructions exist
that have code-gen patterns defined directly, but these instructions are
purely for code-gen and cannot be written in assembly.
Differential Revision: https://reviews.llvm.org/D64012
Patch by James Clarke.
Alex Bradbury [Tue, 16 Jul 2019 03:47:34 +0000 (03:47 +0000)]
[RISCV] Make RISCVELFObjectWriter::getRelocType check IsPCRel
Previously, this function didn't check the IsPCRel argument. But doing so is a
useful check for errors, and also seemingly necessary for FK_Data_4 (which we
produce a R_RISCV_32_PCREL relocation for if IsPCRel).
Other than R_RISCV_32_PCREL, this should be NFC. Future exception handling
related patches will include tests that capture this behaviour.
Re-land "[DebugInfo] Move function from line table to the prologue (NFC)"
In LLDB, when parsing type units, we don't need to parse the whole line
table. Instead, we only need to parse the "support files" from the line
table prologue.
To make that possible, this patch moves the respective functions from
the LineTable into the Prologue. Because I don't think users of the
LineTable should have to know that these files come from the Prologue,
I've left the original methods in place, and made them redirect to the
LineTable.
Michael Liao [Tue, 16 Jul 2019 01:03:06 +0000 (01:03 +0000)]
[InstructionSimplify] Apply sext/trunc after pointer stripping
Summary:
- As the pointer stripping could trace through `addrspacecast` now, need
to sext/trunc the offset to ensure it has the same width as the
pointer after stripping.
[DebugInfo] Move function from line table to the prologue (NFC)
In LLDB, when parsing type units, we don't need to parse the whole line
table. Instead, we only need to parse the "support files" from the line
table prologue.
To make that possible, this patch moves the respective functions from
the LineTable into the Prologue. Because I don't think users of the
LineTable should have to know that these files come from the Prologue,
I've left the original methods in place, and made them redirect to the
LineTable.
As there are some reported miscompiles with AVX512 and performance regressions
in Eigen. Verified with the original committer and testcases will be forthcoming.
[X86] Teach convertToThreeAddress to handle SUB with immediate
We mostly avoid sub with immediate but there are a couple cases that can create them. One is the add 128, %rax -> sub -128, %rax trick in isel. The other is when a SUB immediate gets created for a compare where both the flags and the subtract value is used. If we are unable to linearize the SelectionDAG to satisfy the flag user and the sub result user from the same instruction, we will clone the sub immediate for the two uses. The one that produces flags will eventually become a compare. The other will have its flag output dead, and could then be considered for LEA creation.
I added additional test cases to add.ll to show the the sub -128 trick gets converted to LEA and a case where we don't need to convert it.
This showed up in the current codegen for PR42571.
[WebAssembly] Add missing utility methods for exnref type
Summary:
This adds missing utility methods and copy instruction handling for
`exnref` type and also adds tests.
`tee` instruction tests are missing because `isTee` is currently only
used in ExplicitLocals pass and testing that pass in mir requires
serialization of stackified registers in mir files, which is a bit
nontrivial because `MachineFunctionInfo` only has info of vreg numbers
(which are large integers) but not the mir's register numbers. But this
change is quite trivial anyway.
Summary:
We agreed to rename `except_ref` to `exnref` for consistency with other
reference types in
https://github.com/WebAssembly/exception-handling/issues/79. This also
renames WebAssemblyInstrExceptRef.td to WebAssemblyInstrRef.td in order
to use the file for other reference types in future.
Creates universal binary output file from input files. Currently uses
hard coded value for alignment. Want to get the create functionality
approved before implementing the alignment function.
Summary:
This deletes the ll templates from the functions because they don't need
them (mir files need ll templates only when they have function calls or
BB names that are not numbers).
This also renames the filename to `reg-copy.mir`, because I'm planning
to add some more `reg-*.mir` soon.
[WebAssembly] Assembler: support special floats: infinity / nan
Summary:
These are emitted as identifiers by the InstPrinter, so we should
parse them as such. These could potentially clash with symbols of
the same name, but that is out of our (the WebAssembly backend) control.
Summary:
Enable hoisting and merging m0 defs that are initialized with the same
immediate value. Fixes bug where removed instructions are not considered
to interfere with other inits, and make sure to not hoist inits before block
prologues.
Matt Arsenault [Mon, 15 Jul 2019 21:41:44 +0000 (21:41 +0000)]
AMDGPU: Use standalone MUBUF load patterns
We already do this for the flat and DS instructions, although it is
certainly uglier and more verbose.
This will allow using separate pattern definitions for extload and
zextload. Currently we get away with using a single PatFrag with
custom predicate code to check if the extension type is a zextload or
anyextload. The generic mechanism the global isel emitter understands
treats these as mutually exclusive. I was considering making the
pattern emitter accept zextload or sextload extensions for anyextload
patterns, but in global isel, the different extending loads have
distinct opcodes, and there is currently no mechanism for an opcode
matcher to try multiple (and there probably is very little need for
one beyond this case).
Nick Desaulniers [Mon, 15 Jul 2019 21:16:29 +0000 (21:16 +0000)]
[LoopUnroll+LoopUnswitch] do not transform loops containing callbr
Summary:
There is currently a correctness issue when unrolling loops containing
callbr's where their indirect targets are being updated correctly to the
newly created labels, but their operands are not. This manifests in
unrolled loops where the second and subsequent copies of callbr
instructions have blockaddresses of the label from the first instance of
the unrolled loop, which would result in nonsensical runtime control
flow.
For now, conservatively do not unroll the loop. In the future, I think
we can pursue unrolling such loops provided we transform the cloned
callbr's operands correctly.
Such a transform and its legalities are being discussed in:
https://reviews.llvm.org/D64101
Matt Arsenault [Mon, 15 Jul 2019 21:15:20 +0000 (21:15 +0000)]
TableGen/GlobalISel: Fix handling of truncstore patterns
This was failing to import the AMDGPU truncstore patterns. The
truncating stores from 32-bit to 8/16 were then somehow being
incorrectly selected to a 4-byte store.
A separate check is emitted for the LLT size in comparison to the
specific memory VT, which looks strange to me but makes sense based on
the hierarchy of PatFrags used for the default truncstore PatFrags.
Matt Arsenault [Mon, 15 Jul 2019 20:59:42 +0000 (20:59 +0000)]
TableGen: Add address space to matchers
Currently AMDGPU uses a CodePatPred to check address spaces from the
MachineMemOperand. Introduce a new first class property so that the
existing patterns can be easily modified to uses the new generated
predicate, which will also be handled for GlobalISel.
I would prefer these to match against the pointer type of the
instruction, but that would be difficult to get working with
SelectionDAG compatbility. This is much easier for now and will avoid
a painful tablegen rewrite for all the loads and stores.
I'm also not sure if there's a better way to encode multiple address
spaces in the table, rather than putting the number to expect.
Matt Arsenault [Mon, 15 Jul 2019 20:20:18 +0000 (20:20 +0000)]
AMDGPU/GlobalISel: Allow scalar s1 and/or/xor
If a 1-bit value is in a 32-bit VGPR, the scalar opcodes set SCC to
whether the result is 0. If the inputs are SCC, these can be copied to
a 32-bit SGPR to produce an SCC result.
Add "memtag" sanitizer that detects and mitigates stack memory issues
using armv8.5 Memory Tagging Extension.
It is similar in principle to HWASan, which is a software implementation
of the same idea, but there are enough differencies to warrant a new
sanitizer type IMHO. It is also expected to have very different
performance properties.
The new sanitizer does not have a runtime library (it may grow one
later, along with a "debugging" mode). Similar to SafeStack and
StackProtector, the instrumentation pass (in a follow up change) will be
inserted in all cases, but will only affect functions marked with the
new sanitize_memtag attribute.
Matt Arsenault [Mon, 15 Jul 2019 19:48:36 +0000 (19:48 +0000)]
AMDGPU/GlobalISel: Don't constrain source register of VCC copies
This is a hack until I come up with a better way of dealing with the
pseudo-register banks used for boolean values. If the use instruction
constrains the register, the selector for the def instruction won't
see that the bank was VCC. A 1-bit SReg_32 is could ambiguously have
been SCCRegBank or VCCRegBank in wave32.
This is necessary to successfully select branches with and and/or/xor
condition.
Matt Arsenault [Mon, 15 Jul 2019 19:46:48 +0000 (19:46 +0000)]
AMDGPU/GlobalISel: Fix selecting vcc->vcc bank copies
The extra test change is correct, although how it arrives there is a
bug that needs work. With wave32, the test for isVCC ambiguously
reports true for an SCC or VCC source. A new allocatable pseudo
register class for SCC may be necesssary.