Unfortunately, it is currently impossible to use a PatFrag as part of an output
pattern (the part of the pattern that has instructions in it) in TableGen.
Looking at the current implementation, this was clearly intended to work (there
is already code in place to expand patterns in the output DAG), but is
currently broken by the baked-in type-checking assumption and the order in which
the pattern fragments are processed (output pattern fragments need to be
processed after the instruction definitions are processed).
Fixing this is fairly simple, but requires some way of differentiating output
patterns from the existing input patterns. The simplest way to handle this
seems to be to create a subclass of PatFrag, and so that's what I've done here.
As a simple example, this allows us to write:
def crnot : OutPatFrag<(ops node:$in),
(CRNOR $in, $in)>;
def : Pat<(not i1:$in),
(crnot $in)>;
which captures the core use case: handling of repeated subexpressions inside
of complicated output patterns.
This will be used by an upcoming commit to the PowerPC backend.
llvm-svn: 202450
A ValueType in a pattern dag is a type cast, and GetNumNodeResults should
handle it (the type cast has only one result).
This comes up, for example, during the type checking of pattern fragments, for
example, AArch64's Neon_combine_2d fragment is:
dag Operands = (ops node:$Rm, node:$Rn);
dag Fragment = (v2f64 (concat_vectors (v1f64 node:$Rm), (v1f64 node:$Rn)));
llvm-svn: 198347
This syntax is now preferred:
def : Pat<(subc i32:$b, i32:$c), (SUBCCrr $b, $c)>;
There is no reason to repeat the types in the output pattern.
llvm-svn: 177844
This makes it possible to define instruction patterns like this:
def LDri : F3_2<3, 0b000000,
(outs IntRegs:$dst), (ins MEMri:$addr),
"ld [$addr], $dst",
[(set i32:$dst, (load ADDRri:$addr))]>;
~~~
llvm-svn: 177834
Just like register classes, value types can be used in two ways in
patterns:
(sext_inreg i32:$src, i16)
In a named leaf node like i32:$src, the value type simply provides the
type of the node directly. This simplifies type inference a lot compared
to the current practice of specifiying types indirectly with register
classes.
As an unnamed leaf node, like i16 above, the value type represents
itself as an MVT::Other immediate.
llvm-svn: 177828
A register class can appear as a leaf TreePatternNode with and without a
name:
(COPY_TO_REGCLASS GPR:$src, F8RC)
In a named leaf node like GPR:$src, the register class provides type
information for the named variable represented by the node. The TypeSet
for such a node is the set of value types that the register class can
represent.
In an unnamed leaf node like F8RC above, the register class represents
itself as a kind of immediate. Such a node has the type MVT::i32,
we'll never create a virtual register representing it.
This change makes it possible to remove the special handling of
COPY_TO_REGCLASS in CodeGenDAGPatterns.cpp.
llvm-svn: 177825
of complex instruction operands (e.g. address modes).
Currently, if a Pat pattern creates an instruction that has a complex
operand (i.e. one that consists of multiple sub-operands at the MI
level), this operand must match a ComplexPattern DAG pattern with the
correct number of output operands.
This commit extends TableGen to alternatively allow match a complex
operands against multiple separate operands at the DAG level.
This allows using Pat patterns to match pre-increment nodes like
pre_store (which must have separate operands at the DAG level) onto
an instruction pattern that uses a multi-operand memory operand,
like the following example on PowerPC (will be committed as a
follow-on patch):
def STWU : DForm_1<37, (outs ptr_rc:$ea_res), (ins GPRC:$rS, memri:$dst),
"stwu $rS, $dst", LdStStoreUpd, []>,
RegConstraint<"$dst.reg = $ea_res">, NoEncode<"$ea_res">;
def : Pat<(pre_store GPRC:$rS, ptr_rc:$ptrreg, iaddroff:$ptroff),
(STWU GPRC:$rS, iaddroff:$ptroff, ptr_rc:$ptrreg)>;
Here, the pair of "ptroff" and "ptrreg" operands is matched onto the
complex operand "dst" of class "memri" in the "STWU" instruction.
Approved by Jakob Stoklund Olesen.
llvm-svn: 177428
Most places can use PrintFatalError as the unwinding mechanism was not
used for anything other than printing the error. The single exception
was CodeGenDAGPatterns.cpp, where intermediate errors during type
resolution were ignored to simplify incremental platform development.
This use is replaced by an error flag in TreePattern and bailout earlier
in various places if it is set.
llvm-svn: 166712
Some of these dyn_cast<>'s would be better phrased as isa<> or cast<>.
That will happen in a future patch.
There are also two dyn_cast_or_null<>'s slipped in instead of
dyn_cast<>'s, since they were causing crashes with just dyn_cast<>.
llvm-svn: 165646
This is a generally useful utility; there's no reason to have it hidden
in CodeGenDAGPatterns.cpp.
Also, rename it to fit the other comparators in Record.h
Review by Jakob.
llvm-svn: 164189
Previously, instructions without a primary patterns wouldn't get their
properties inferred. Now, we use all single-instruction patterns for
inference, including 'def : Pat<>' instances.
This causes a lot of instruction flags to change.
- Many instructions no longer have the UnmodeledSideEffects flag because
their flags are now inferred from a pattern.
- Instructions with intrinsics will get a mayStore flag if they already
have UnmodeledSideEffects and a mayLoad flag if they already have
mayStore. This is because intrinsics properties are linear.
- Instructions with atomic_load patterns get a mayStore flag because
atomic loads can't be reordered. The correct workaround is to create
pseudo-instructions instead of using normal loads. PR13693.
llvm-svn: 162614
Instructions are now only marked as variadic if they use variable_ops in
their ins list.
A variadic SDNode is typically used for call nodes that have the call
arguments as operands.
A variadic MachineInstr can actually encode a variable number of
operands, for example ARM's stm/ldm instructions. A call instruction
does not have to be variadic. The call argument registers are added as
implicit operands.
This change remove the MCID::Variadic flags from most call and return
instructions, allowing us to better verify their operands.
llvm-svn: 162599
It is now allowed to explicitly set hasSideEffects, mayStore, and
mayLoad on instructions with patterns.
Verify that the patterns are consistent with the explicit flags.
llvm-svn: 162569
Emit TableGen errors if guessInstructionProperties is 0 and
instruction properties can't be inferred from patterns.
Allow explicit instruction properties even when they can be inferred.
This patch doesn't change the TableGen output. Redundant properties
are not yet verified because the tree has errors.
llvm-svn: 162516
A standalone pattern defined in a multiclass expansion should handle
null_frag references just like patterns on instructions. Follow-up to
r160333.
llvm-svn: 160384
Define a 'null_frag' SDPatternOperator node, which if referenced in an
instruction Pattern, results in the pattern being collapsed to be as-if
'[]' had been specified instead. This allows supporting a multiclass
definition where some instaniations have ISel patterns associated and
others do not.
For example,
multiclass myMulti<RegisterClass rc, SDPatternOperator OpNode = null_frag> {
def _x : myI<(outs rc:), (ins rc:), []>;
def _r : myI<(outs rc:), (ins rc:), [(set rc:, (OpNode rc:))]>;
}
defm foo : myMulti<GRa, not>;
defm bar : myMulti<GRb>;
llvm-svn: 160333
TableGen infers unmodeled side effects on instructions without a
pattern. Fix some instruction definitions where that was overlooked.
Also raise an error if a rematerializable instruction has unmodeled side
effects. That doen't make any sense.
llvm-svn: 141929
Make all of the RecTy constructors private, and use get() factory
methods instead. Return singleton instances when it makes sense.
ListTy instance pointers are stored in the element RecTy instance.
BitsRecTy instance pointers, one per length, are stored in a static vector.
Also unique DefInit instances. A Record has a unique DefInit which
has a unique RecordRecTy instance.
This saves some 200k-300k RecTy allocations when parsing ARM.td. It
reduces TableGen's heap usage by almost 50%.
llvm-svn: 135399
Manage Inits in a FoldingSet. This provides several benefits:
- Memory for Inits is properly managed
- Duplicate Inits are folded into Flyweights, saving memory
- It enforces const-correctness, protecting against certain classes
of bugs
The above benefits allow Inits to be used in more contexts, which in
turn provides more dynamism to TableGen. This enhanced capability
will be used by the AVX code generator to a fold common patterns
together.
llvm-svn: 134907
kind of predicate: one that is specific to imm nodes. The predicate function
specified here just checks an int64_t directly instead of messing around with
SDNode's. The virtue of this is that it means that fastisel and other things
can reason about these predicates.
llvm-svn: 129675
structure and fix some fixmes. We now have a TreePredicateFn class
that handles all of the decoding of these things. This is an internal
cleanup that has no impact on the code generated by tblgen.
llvm-svn: 129670
makes type checking for extract_subvector and insert_subvector more
robust and will allow stricter typechecking of more patterns in the
future.
This change handles int and fp as disjoint sets so that it will
enforce integer types to be smaller than the largest integer type and
fp types to be smaller than the largest fp type. There is no attempt
to check type sizes across the int/fp sets.
llvm-svn: 124672
This will be used to check patterns referencing a forthcoming
INSERT_SUBVECTOR SDNode. INSERT_SUBVECTOR in turn is very useful for
matching to VINSERTF128 instructions and complements the already
existing EXTRACT_SUBVECTOR SDNode.
llvm-svn: 124145
This is the beginning of purely symbolic subregister indices, but we need a bit
of jiggling before the explicit numeric indices can be completely removed.
llvm-svn: 104492
and those derived from them. These are obnoxious because
they were written as: PatLeaf<(bitconvert). Not having an
argument was foiling adding better type checking for operand
count matching up with what was required (in this case,
bitconvert always requires an operand!)
llvm-svn: 99759
transforming it into (add (i32 GPR), 4). This allows us to write type
generic multi patterns and have tblgen automatically drop the bitconvert
in the case when the types align. This allows us to fold an extra load
in the changed testcase.
llvm-svn: 99756
from two places in CodeGenDAGPatterns.cpp, and
use it in DAGISelMatcherGen.cpp instead of using
an incorrect predicate that happened to get lucky
on our current targets.
llvm-svn: 99726
results forward. We can now handle an instruction that
produces one implicit def and one result instead of one or
the other when not at the root of the pattern.
llvm-svn: 99725
to maintain a list of types (one for each result of
the node) instead of a single type. There are liberal
hacks added to emulate the old behavior in various
situations, but they can start disolving now.
llvm-svn: 98999
Benjamin Kramer