This commit refactors the current pass manager support to allow for
operation agnostic pass managers. This allows for a series of passes
to be executed on any viable pass manager root operation, instead
of one specific operation type. Op-agnostic/generic pass managers
only allow for adding op-agnostic passes.
These types of pass managers are extremely useful when constructing
pass pipelines that can apply to many different types of operations,
e.g., the default inliner simplification pipeline. With the advent of
interface/trait passes, this support can be used to define FunctionOpInterface
pass managers, or other pass managers that effectively operate on
specific interfaces/traits/etc (see #52916 for an example).
Differential Revision: https://reviews.llvm.org/D123536
The printer is now resilient to invalid IR and will already automatically
fallback to the generic form on invalid IR. Using the generic printer on
pass failure was a conservative option before the printer was made
failsafe.
Reviewed By: lattner, rriddle, jpienaar, bondhugula
Differential Revision: https://reviews.llvm.org/D123915
The generic form of the op is too verbose and in some cases not
readable. On pass failure, ops have been so far printed in generic form
to provide a (stronger) guarantee that the IR print succeeds. However,
in a large number of pass failure cases, the IR is still valid and
the custom printers for the ops will succeed. In fact, readability is
highly desirable post pass failure. This revision provides an option to
print ops in their custom/pretty-printed form on IR failure -- this
option is unsafe and there is no guarantee it will succeed. It's
disabled by default and can be turned on only if needed.
Differential Revision: https://reviews.llvm.org/D123893
With this change, there's going to be a clear distinction between LLVM
and MLIR pass maanger options (e.g. `-mlir-print-after-all` vs
`-print-after-all`). This change is desirable from the point of view of
projects that depend on both LLVM and MLIR, e.g. Flang.
For consistency, all pass manager options in MLIR are prefixed with
`mlir-`, even options that don't have equivalents in LLVM .
Differential Revision: https://reviews.llvm.org/D123495
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
This significantly simplifies the boilerplate necessary for passes
to define nested pass pipelines.
Differential Revision: https://reviews.llvm.org/D122880
ListOption currently uses llvm:🆑:list under the hood, but the usages
of ListOption are generally a tad different from llvm:🆑:list. This
commit codifies this by making ListOption implicitly comma separated,
and removes the explicit flag set for all of the current list options.
The new parsing for comma separation of ListOption also adds in support
for skipping over delimited sub-ranges (i.e. {}, [], (), "", ''). This
more easily supports nested options that use those as part of the
format, and this constraint (balanced delimiters) is already codified
in the syntax of pass pipelines.
See https://discourse.llvm.org/t/list-of-lists-pass-option/5950 for
related discussion
Differential Revision: https://reviews.llvm.org/D122879
This commit moves FuncOp out of the builtin dialect, and into the Func
dialect. This move has been planned in some capacity from the moment
we made FuncOp an operation (years ago). This commit handles the
functional aspects of the move, but various aspects are left untouched
to ease migration: func::FuncOp is re-exported into mlir to reduce
the actual API churn, the assembly format still accepts the unqualified
`func`. These temporary measures will remain for a little while to
simplify migration before being removed.
Differential Revision: https://reviews.llvm.org/D121266
The current decision of when to run the verifier is running on the
assumption that nested passes can't affect the validity of the parent
operation, which isn't true. Parent operations may attach any number
of constraints on nested operations, which may not necessarily be
captured (or shouldn't be captured) at a smaller granularity.
This commit rectifies this by properly running the verifier after an
OpToOpAdaptor pass. To avoid an explosive increase in compile time,
we only run verification on the parent operation itself. To do this, a
flag to mlir::verify is added to avoid recursive verification if it isn't
desired.
Fixes#54288
Differential Revision: https://reviews.llvm.org/D121836
This commit adds a new hook Pass `bool canScheduleOn(RegisteredOperationName)` that
indicates if the given pass can be scheduled on operations of the given type. This makes it
easier to define constraints on generic passes without a) adding conditional checks to
the beginning of the `runOnOperation`, or b) defining a new pass type that forwards
from `runOnOperation` (after checking the invariants) to a new hook. This new hook is
used to implement an `InterfacePass` pass class, that represents a generic pass that
runs on operations of the given interface type.
The PassManager will also verify that passes added to a pass manager can actually be
scheduled on that pass manager, meaning that we will properly error when an Interface
is scheduled on an operation that doesn't actually implement that interface.
Differential Revision: https://reviews.llvm.org/D120791
The option parser currently does not properly handle nested options, meaning that
in some cases we can print pass pipelines that we can't actually parse back in. For example,
from #52885 we currently can't parse in inliner pipelines that have nested pipeline strings.
This commit adds handling for string values (e.g. "...") and nested options
(e.g. `foo{baz{bar=10 pizza=11}}`).
Fixes#52885
Differential Revision: https://reviews.llvm.org/D118078
This overload parses a pipeline string that contains the anchor operation type, and returns an OpPassManager
corresponding to the provided pipeline. This is useful for various situations, such as dynamic pass pipelines
which are not anchored within a parent pass pipeline.
fixes#52813
Differential Revision: https://reviews.llvm.org/D116525
There have been a few API pieces remaining to allow for a smooth transition for
downstream users, but these have been up for a few months now. After this only
the C API will have reference to "Identifier", but those will be reworked in a followup.
The main updates are:
* Identifier -> StringAttr
* StringAttr::get requires the context as the first parameter
- i.e. `Identifier::get("...", ctx)` -> `StringAttr::get(ctx, "...")`
Reviewed By: mehdi_amini
Differential Revision: https://reviews.llvm.org/D116626
This allows to clear an OpPassManager and populated it again with a new
pipeline, while preserving all the other options (including instrumentations).
Differential Revision: https://reviews.llvm.org/D112393
This avoids keeping references to passes that may be freed by
the time that the pass manager has finished executing (in the
non-crash case).
Fixes PR#52069
Differential Revision: https://reviews.llvm.org/D111106
In D104421, we changed the API for pass registration.
Before you would write:
void registerPass("my-pass", "My Pass Description.",
[] { return createMyPass(); });
while now you’d only write:
void registerPass([] { return createMyPass(); });
If you’re using TableGen to define your pass registration, you shouldn’t have anything to do. If you’re using directly the C++ API here are some changes.
Your project may also be broken even if you use TableGen and you call the
generated registration API in case your pass implementation didn’t inherit from
the MyPassBase class generated by TableGen.
If you don't use TableGen, the "my-pass" and "My Pass Description." fields must
be provided by overriding methods on the pass itself:
llvm::StringRef getArgument() const final { return "my-pass"; }
llvm::StringRef getDescription() const final {
return "My Pass Description.";
}
Reviewed By: rriddle
Differential Revision: https://reviews.llvm.org/D104429
Historically the builtin dialect has had an empty namespace. This has unfortunately created a very awkward situation, where many utilities either have to special case the empty namespace, or just don't work at all right now. This revision adds a namespace to the builtin dialect, and starts to cleanup some of the utilities to no longer handle empty namespaces. For now, the assembly form of builtin operations does not require the `builtin.` prefix. (This should likely be re-evaluated though)
Differential Revision: https://reviews.llvm.org/D105149
This revision refactors the usage of multithreaded utilities in MLIR to use a common
thread pool within the MLIR context, in addition to a new utility that makes writing
multi-threaded code in MLIR less error prone. Using a unified thread pool brings about
several advantages:
* Better thread usage and more control
We currently use the static llvm threading utilities, which do not allow multiple
levels of asynchronous scheduling (even if there are open threads). This is due to
how the current TaskGroup structure works, which only allows one truly multithreaded
instance at a time. By having our own ThreadPool we gain more control and flexibility
over our job/thread scheduling, and in a followup can enable threading more parts of
the compiler.
* The static nature of TaskGroup causes issues in certain configurations
Due to the static nature of TaskGroup, there have been quite a few problems related to
destruction that have caused several downstream projects to disable threading. See
D104207 for discussion on some related fallout. By having a ThreadPool scoped to
the context, we don't have to worry about destruction and can ensure that any
additional MLIR thread usage ends when the context is destroyed.
Differential Revision: https://reviews.llvm.org/D104516
This patch changes the (not recommended) static registration API from:
static PassRegistration<MyPass> reg("my-pass", "My Pass Description.");
to:
static PassRegistration<MyPass> reg;
And the explicit registration from:
void registerPass("my-pass", "My Pass Description.",
[] { return createMyPass(); });
To:
void registerPass([] { return createMyPass(); });
It is expected that Pass implementations overrides the getArgument() method
instead. This will ensure that pipeline description can be printed and parsed
back.
Differential Revision: https://reviews.llvm.org/D104421
This changes the pass manager to not rerun the verifier when a pass says it
didn't change anything or after an OpToOpPassAdaptor, since neither of those
cases need verification (and if the pass lied, then there will be much larger
semantic problems than will be caught by the verifier).
This maintains behavior in EXPENSIVE_CHECKS mode.
Differential Revision: https://reviews.llvm.org/D104243
This allows for better interaction with tools (such as mlir-lsp-server), as it separates the IR into separate modules for consecutive dumps.
Differential Revision: https://reviews.llvm.org/D104073
This simplifies various pieces of code that interact with the pass registry, e.g. this removes the need to register passes to get accurate pass pipelines descriptions when generating crash reproducers.
Differential Revision: https://reviews.llvm.org/D101880
The current implementation has several key limitations and weirdness, e.g local reproducers don't support dynamic pass pipelines, error messages don't include the passes that failed, etc. This revision refactors the implementation to support more use cases, and also be much cleaner.
The main change in this revision, aside from moving the implementation out of Pass.cpp and into its own file, is the addition of a crash recovery pass instrumentation. For local reproducers, this instrumentation handles setting up the recovery context before executing each pass. For global reproducers, the instrumentation is used to provide a more detailed error message, containing information about which passes are running and on which operations.
Example of new message:
```
error: Failures have been detected while processing an MLIR pass pipeline
note: Pipeline failed while executing [`TestCrashRecoveryPass` on 'module' operation: @foo]: reproducer generated at `crash-recovery.mlir.tmp`
```
Differential Revision: https://reviews.llvm.org/D101854
This flag will print the IR after a pass only in the case where the pass failed. This can be useful to more easily view the invalid IR, without needing to print after every pass in the pipeline.
Differential Revision: https://reviews.llvm.org/D101853
This factors out the pass timing code into a separate `TimingManager`
that can be plugged into the `PassManager` from the outside. Users are
able to provide their own implementation of this manager, and use it to
time additional code paths outside of the pass manager. Also allows for
multiple `PassManager`s to run and contribute to a single timing report.
More specifically, moves most of the existing infrastructure in
`Pass/PassTiming.cpp` into a new `Support/Timing.cpp` file and adds a
public interface in `Support/Timing.h`. The `PassTiming` instrumentation
becomes a wrapper around the new timing infrastructure which adapts the
instrumentation callbacks to the new timers.
Reviewed By: rriddle, lattner
Differential Revision: https://reviews.llvm.org/D100647
In LLVM_ENABLE_STATS=0 builds, `llvm::Statistic` maps to `llvm::NoopStatistic`
but has 3 mostly unused pointers. GlobalOpt considers that the pointers can
potentially retain allocated objects, so GlobalOpt cannot optimize out the
`NoopStatistic` variables (see D69428 for more context), wasting 23KiB for stage
2 clang.
This patch makes `NoopStatistic` empty and thus reclaims the wasted space. The
clang size is even smaller than applying D69428 (slightly smaller in both .bss and
.text).
```
# This means the D69428 optimization on clang is mostly nullified by this patch.
HEAD+D69428: size(.bss) = 0x0725a8
HEAD+D101211: size(.bss) = 0x072238
# bloaty - HEAD+D69428 vs HEAD+D101211
# With D101211, we also save a lot of string table space (.rodata).
FILE SIZE VM SIZE
-------------- --------------
-0.0% -32 -0.0% -24 .eh_frame
-0.0% -336 [ = ] 0 .symtab
-0.0% -360 [ = ] 0 .strtab
[ = ] 0 -0.2% -880 .bss
-0.0% -2.11Ki -0.0% -2.11Ki .rodata
-0.0% -2.89Ki -0.0% -2.89Ki .text
-0.0% -5.71Ki -0.0% -5.88Ki TOTAL
```
Note: LoopFuse is a disabled pass. For now this patch adds
`#if LLVM_ENABLE_STATS` so `OptimizationRemarkMissed` is skipped in
LLVM_ENABLE_STATS==0 builds. If these `OptimizationRemarkMissed` are useful in
LLVM_ENABLE_STATS==0 builds, we can replace `llvm::Statistic` with
`llvm::TrackingStatistic`, or use a different abstraction to keep track of the strings.
Similarly, skip the code in `mlir/lib/Pass/PassStatistics.cpp` which
calls `getName`/`getDesc`/`getValue`.
Reviewed By: lattner
Differential Revision: https://reviews.llvm.org/D101211