Summary:
While here, simplify the lexer a bit by eliminating the unneeded 'operator'
classification of certain sigils, they can just be treated as 'punctuation'.
Reviewers: rriddle!
Subscribers: mehdi_amini, rriddle, jpienaar, burmako, shauheen, antiagainst, nicolasvasilache, arpith-jacob, mgester, lucyrfox, liufengdb, Joonsoo, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D76647
Thus far IntegerType has been signless: a value of IntegerType does
not have a sign intrinsically and it's up to the specific operation
to decide how to interpret those bits. For example, std.addi does
two's complement arithmetic, and std.divis/std.diviu treats the first
bit as a sign.
This design choice was made some time ago when we did't have lots
of dialects and dialects were more rigid. Today we have much more
extensible infrastructure and different dialect may want different
modelling over integer signedness. So while we can say we want
signless integers in the standard dialect, we cannot dictate for
others. Requiring each dialect to model the signedness semantics
with another set of custom types is duplicating the functionality
everywhere, considering the fundamental role integer types play.
This CL extends the IntegerType with a signedness semantics bit.
This gives each dialect an option to opt in signedness semantics
if that's what they want and helps code sharing. The parser is
modified to recognize `si[1-9][0-9]*` and `ui[1-9][0-9]*` as
signed and unsigned integer types, respectively, leaving the
original `i[1-9][0-9]*` to continue to mean no indication over
signedness semantics. All existing dialects are not affected (yet)
as this is a feature to opt in.
More discussions can be found at:
https://groups.google.com/a/tensorflow.org/d/msg/mlir/XmkV8HOPWpo/7O4X0Nb_AQAJ
Differential Revision: https://reviews.llvm.org/D72533
The restriction that symbols can only have identifier names is arbitrary, and artificially limits the names that a symbol may have. This change adds support for parsing and printing symbols that don't fit in the 'bare-identifier' grammar by printing the reference in quotes, e.g. @"0_my_reference" can now be used as a symbol name.
PiperOrigin-RevId: 273644768
Lexer methods were added progressively as implementation advanced. The rest of
MLIR now tends to sort methods alphabetically for better discoverability in
absence of tooling. Sort the lexer methods as well.
PiperOrigin-RevId: 262406992
LLVM function type has first-class support for variadic functions. In the
current lowering pipeline, it is emulated using an attribute on functions of
standard function type. In LLVMFuncOp that has LLVM function type, this can be
modeled directly. Introduce parsing support for variadic arguments to the
function and use it to support variadic function declarations in LLVMFuncOp.
Function definitions are currently not supported as that would require modeling
va_start/va_end LLVM intrinsics in the dialect and we don't yet have a
consistent story for LLVM intrinsics.
PiperOrigin-RevId: 262372651
This allows for the attribute to hold symbolic references to other operations than FuncOp. This also allows for removing the dependence on FuncOp from the base Builder.
PiperOrigin-RevId: 257650017
Now that Locations are attributes, they have direct access to the MLIR context. This allows for simplifying error emission by removing unnecessary context lookups.
PiperOrigin-RevId: 255112791
`#` alias `=` attribute-value
This also allows for dialects to define aliases for attributes in the AsmPrinter. The printer supports two types of attribute aliases, 'direct' and 'kind'.
* Direct aliases are synonymous with the current support for type aliases, i.e. this maps an alias to a specific instance of an attribute.
// A direct alias ("foo_str") for the string attribute "foo".
#foo_str = "foo"
* Kind aliases generates unique names for all instances of a given attribute kind. The generated aliases are of the form: `alias[0-9]+`.
// A kind alias ("strattr") for all string attributes could generate.
#strattr0 = "foo"
#strattr1 = "bar"
...
#strattrN = "baz"
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PiperOrigin-RevId: 246851916
The Diagnostic class contains all of the information necessary to report a diagnostic to the DiagnosticEngine. It should generally not be constructed directly, and instead used transitively via InFlightDiagnostic. A diagnostic is currently comprised of several different elements:
* A severity level.
* A source Location.
* A list of DiagnosticArguments that help compose and comprise the output message.
* A DiagnosticArgument represents any value that may be part of the diagnostic, e.g. string, integer, Type, Attribute, etc.
* Arguments can be added to the diagnostic via the stream(<<) operator.
* (In a future cl) A list of attached notes.
* These are in the form of other diagnostics that provide supplemental information to the main diagnostic, but do not have context on their own.
The InFlightDiagnostic class represents an RAII wrapper around a Diagnostic that is set to be reported with the diagnostic engine. This allows for the user to modify a diagnostic that is inflight. The internally wrapped diagnostic can be reported directly or automatically upon destruction.
These classes allow for more natural composition of diagnostics by removing the restriction that the message of a diagnostic is comprised of a single Twine. They should also allow for nice incremental improvements to the diagnostics experience in the future, e.g. formatv style diagnostics.
Simple Example:
emitError(loc, "integer bitwidth is limited to " + Twine(IntegerType::kMaxWidth) + " bits");
emitError(loc) << "integer bitwidth is limited to " << IntegerType::kMaxWidth << " bits";
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PiperOrigin-RevId: 246526439
Existing IR syntax is ambiguous in type declarations in presence of zero sizes.
In particular, `0x1` in the type size can be interpreted as either a
hexadecimal literal corresponding to 1, or as two distinct decimal literals
separated by an `x` for sizes. Furthermore, the shape `<0xi32>` fails lexing
because it is expected to be an integer literal.
Fix the lexer to treat `0xi32` as an integer literal `0` followed by a bare
identifier `xi32` (look one character ahead and early return instead of
erroring out).
Disallow hexadecimal literals in type declarations and forcibly split the token
into multiple parts while parsing the type. Note that the splitting trick has
been already present to separate the element type from the preceding `x`
character.
PiperOrigin-RevId: 232880373
Nothing in the loop can (legally) cause curPtr -> nullptr. And if it did, we
would null dereference right below anyway.
This loop still reads funny to me but doesn't make me stare at it and wonder
what I am missing anymore.
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PiperOrigin-RevId: 232062076