Summary:
TableGen interprets braces ('{}') in the asm string of instruction aliases as
variants but when defining aliases with literal braces they have to be escaped
to prevent them being removed.
Braces are escaped with '\\', for example:
def FooBraces : InstAlias<"foo \\{$imm\\}", (foo IntOperand:$imm)>;
Although when TableGen is emitting the assembly writer (-gen-asm-writer)
the AsmString that gets emitted is:
AsmString = "foo \{$\x01\}";
In c/c++ braces don't need to be escaped which causes compilation
warnings:
warning: use of non-standard escape character '\{' [-Wpedantic]
This patch fixes the issue by unescaping the flattened alias asm string
in the asm writer, by replacing '\{\}' with '{}'.
Reviewed By: hfinkel
Differential Revision: https://reviews.llvm.org/D79991
- Argument attribute needs specifiying through `ArgIndex<n>`
(corresponding to `FirstArgIndex`) to distinguish explicitly from the
index number from the overloaded type list.
- In addition, `RetIndex` (corresponding to `ReturnIndex`) and
`FuncIndex` (corresponding to `FunctionIndex`) are introduced for us
to associate attributes on the return value and potentially function
itself.
Differential Revision: https://reviews.llvm.org/D80422
Summary:
In TableGen's instruction selection table generator, references to
register classes were handled by generating a matcher table entry in the
form of "EmitStringInteger, MVT::i32, 'RegisterClassID'". This ID is in
fact the enum integer value corresponding to the register class.
However, both the table generator and the table consumer
(SelectionDAGISel) assume that this ID is less than or equal to 127,
i.e. at most 7 bits. Values greater than this threshold cause completely
wrong behaviours in the instruction selection process.
This patch adds a check to determine if the enum integer value is
greater than the limit of 127. In finding so, the generator emits an
"EmitInteger" instead, which properly supports values with arbitrary
sizes.
Commit f8d044bbcf fixed the very same bug
for register subindices. The present patch now extends this cover to
register classes.
Reviewers: rampitec
Reviewed By: rampitec
Subscribers: llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D79705
This was hitting the default instruction constraint code which uses
the register classes in the instruction def, which REG_SEQUENCE does
not have.
Fixes not constraining the register class for AMDGPU fneg/fabs
patterns, which would fail when the use was another generic,
unconstrained instruction.
Another oddity I noticed is that the temporary registers are created
with an unnecessary, but incorrect 16-bit LLT but this shouldn't
matter.
I'm also still unclear why root and sub-instructions have to be
handled differently.
For context, the proposed RISC-V bit manipulation extension has a subset
of instructions which require one of two SubtargetFeatures to be
enabled, 'zbb' or 'zbp', and there is no defined feature which both of
these can imply to use as a constraint either (see comments in D65649).
AssemblerPredicates allow multiple SubtargetFeatures to be declared in
the "AssemblerCondString" field, separated by commas, and this means
that the two features must both be enabled. There is no equivalent to
say that _either_ feature X or feature Y must be enabled, short of
creating a dummy SubtargetFeature for this purpose and having features X
and Y imply the new feature.
To solve the case where X or Y is needed without adding a new feature,
and to better match a typical TableGen style, this replaces the existing
"AssemblerCondString" with a dag "AssemblerCondDag" which represents the
same information. Two operators are defined for use with
AssemblerCondDag, "all_of", which matches the current behaviour, and
"any_of", which adds the new proposed ORing features functionality.
This was originally proposed in the RFC at
http://lists.llvm.org/pipermail/llvm-dev/2020-February/139138.html
Changes to all current backends are mechanical to support the replaced
functionality, and are NFCI.
At this stage, it is illegal to combine features with ands and ors in a
single AssemblerCondDag. I suspect this case is sufficiently rare that
adding more complex changes to support it are unnecessary.
Differential Revision: https://reviews.llvm.org/D74338
This was checking for default operands in the current DAG instruction,
rather than the correct result operand list. I'm not entirly sure how
this managed to work before, but was failing for me when multiple
default operands were overridden.
Summary:
Previously TableGen would crash trying to print the undefined value as
an integer.
Change-Id: I3900071ceaa07c26acafb33bc49966d7d7a02828
Reviewers: nhaehnle
Subscribers: llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D74210
Summary:
In the DAG pattern backend, `SimplifyTree` simplifies a pattern by
removing bitconverts between two identical types. But that function is
also run on the fragments list in instances of `PatFrags`, in which
the types haven't been specified yet. So the input and output of the
bitconvert always evaluate to the empty set of types, which makes them
compare equal. So the test always passes, and bitconverts are
unconditionally removed from the PatFrag RHS.
Fixed by spotting the empty type set and using it to inhibit the
optimization.
Reviewers: nhaehnle, hfinkel
Reviewed By: nhaehnle
Subscribers: llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D74627
This reverts commit 80a34ae311 with fixes.
Previously, since bots turning on EXPENSIVE_CHECKS are essentially turning on
MachineVerifierPass by default on X86 and the fact that
inline-asm-avx-v-constraint-32bit.ll and inline-asm-avx512vl-v-constraint-32bit.ll
are not expected to generate functioning machine code, this would go
down to `report_fatal_error` in MachineVerifierPass. Here passing
`-verify-machineinstrs=0` to make the intent explicit.
This reverts commit 80a34ae311 with fixes.
On bots llvm-clang-x86_64-expensive-checks-ubuntu and
llvm-clang-x86_64-expensive-checks-debian only,
llc returns 0 for these two tests unexpectedly. I tweaked the RUN line a little
bit in the hope that LIT is the culprit since this change is not in the
codepath these tests are testing.
llvm\test\CodeGen\X86\inline-asm-avx-v-constraint-32bit.ll
llvm\test\CodeGen\X86\inline-asm-avx512vl-v-constraint-32bit.ll
Tablegen's DAGISelMatcher emits integers in a VBR format,
so if an integer is below 128 it can fit into a single
byte, otherwise high bit is set, next byte is used etc.
MatcherTable is essentially an unsigned char table. When
SelectionDAGISel parses the table it does a reverse translation.
In a situation when numeric value of an integer to emit is
unknown it can be emitted not as OPC_EmitInteger but as
OPC_EmitStringInteger using a symbolic name of the value.
In this situation the value should not exceed 127.
One of the situations when OPC_EmitStringInteger is used is
if we need to emit a subreg into a matcher table. However,
number of subregs can exceed 127. Currently last defined subreg
for AMDGPU is 192. That results in a silent bug in the ISel
with matcher reading from an invalid offset.
Fixed this bug to emit actual VBR encoded value for a subregs
which value exceeds 127.
Differential Revision: https://reviews.llvm.org/D74368
This reverts commit rGcd5b308b828e, rGcd5b308b828e, rG8cedf0e2994c.
There are issues to be investigated for polly bots and bots turning on
EXPENSIVE_CHECKS.
Summary:
There are a few field init values that are concrete but not complete/foldable (e.g. `?`). This allows for using those values as initializers without erroring out.
Example:
```
class A {
string value = ?;
}
class B<A impl> : A {
let value = impl.value; // This currently emits an error.
let value = ?; // This doesn't emit an error.
}
```
Differential Revision: https://reviews.llvm.org/D74360
Summary:
The following example gives the error message "expected value of type
'bits<32>', got 'bit'" on the assignment.
class Instruction { bits<32> encoding; }
def foo: Instruction { let encoding{10} = !eq(0, 1); }
But there's nothing wrong with this code: 'bit' is a perfectly good
type for the RHS of an assignment to a //single bit// of an
instruction encoding.
The problem is that `ParseBodyItem` is accidentally type-checking the
RHS against the full type of the `encoding` field, without adjusting
it in the case where we're only assigning to a subset of the bits. The
fix is trivial.
Reviewers: nhaehnle, hfinkel
Reviewed By: hfinkel
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D74220
This previously only handled EXTRACT_SUBREGs from leafs, such as
operands directly in the original output. Handle extracting from a
result instruction.
Summary:
This patch could be treated as a rebase of D33960. It also fixes PR35547.
A fix for `llvm/test/Other/close-stderr.ll` is proposed in D68164. Seems
the consensus is that the test is passing by chance and I'm not
sure how important it is for us. So it is removed like in D33960 for now.
The rest of the test fixes are just adding `--crash` flag to `not` tool.
** The reason it fixes PR35547 is
`exit` does cleanup including calling class destructor whereas `abort`
does not do any cleanup. In multithreading environment such as ThinLTO or JIT,
threads may share states which mostly are ManagedStatic<>. If faulting thread
tearing down a class when another thread is using it, there are chances of
memory corruption. This is bad 1. It will stop error reporting like pretty
stack printer; 2. The memory corruption is distracting and nondeterministic in
terms of error message, and corruption type (depending one the timing, it
could be double free, heap free after use, etc.).
Reviewers: rnk, chandlerc, zturner, sepavloff, MaskRay, espindola
Reviewed By: rnk, MaskRay
Subscribers: wuzish, jholewinski, qcolombet, dschuff, jyknight, emaste, sdardis, nemanjai, jvesely, nhaehnle, sbc100, arichardson, jgravelle-google, aheejin, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, lenary, s.egerton, pzheng, cfe-commits, MaskRay, filcab, davide, MatzeB, mehdi_amini, hiraditya, steven_wu, dexonsmith, rupprecht, seiya, llvm-commits
Tags: #llvm, #clang
Differential Revision: https://reviews.llvm.org/D67847
Summary:
This allows you to make some of the defs in a multiclass or `foreach`
conditional on an expression computed from the parameters or iteration
variables.
It was already possible to simulate an if statement using a `foreach`
with a dummy iteration variable and a list constructed using `!if` so
that it had length 0 or 1 depending on the condition, e.g.
foreach unusedIterationVar = !if(condition, [1], []<int>) in { ... }
But this syntax is nicer to read, and also more convenient because it
allows an else clause.
To avoid upheaval in the implementation, I've implemented `if` as pure
syntactic sugar on the `foreach` implementation: internally, `ParseIf`
actually does construct exactly the kind of foreach shown above (and
another reversed one for the else clause if present).
Reviewers: nhaehnle, hfinkel
Reviewed By: hfinkel
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D71474
Summary:
This allows you to define a global or local variable to an arbitrary
value, and refer to it in subsequent definitions.
The main use I anticipate for this is if you have to compute some
difficult function of the parameters of a multiclass, and then use it
many times. For example:
multiclass Foo<int i, string s> {
defvar op = !cast<BaseClass>("whatnot_" # s # "_" # i);
def myRecord {
dag a = (op this, (op that, the other), (op x, y, z));
int b = op.subfield;
}
def myOtherRecord<"template params including", op>;
}
There are a couple of ways to do this already, but they're not really
satisfactory. You can replace `defvar x = y` with a loop over a
singleton list, `foreach x = [y] in { ... }` - but that's unintuitive
to someone who hasn't seen that workaround idiom before, and requires
an extra pair of braces that you often didn't really want. Or you can
define a nested pair of multiclasses, with the inner one taking `x` as
a template parameter, and the outer one instantiating it just once
with the desired value of `x` computed from its other parameters - but
that makes it awkward to sequentially compute each value based on the
previous ones. I think `defvar` makes things considerably easier.
You can also use `defvar` at the top level, where it inserts globals
into the same map used by `defset`. That allows you to define global
constants without having to make a dummy record for them to live in:
defvar MAX_BUFSIZE = 512;
// previously:
// def Dummy { int MAX_BUFSIZE = 512; }
// and then refer to Dummy.MAX_BUFSIZE everywhere
Reviewers: nhaehnle, hfinkel
Reviewed By: hfinkel
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D71407
For arguments that are not expected to be materialized with
G_CONSTANT, this was emitting predicates which could never match. It
was first adding a meaningless LLT check, which would always fail due
to the operand not being a register.
Infer the cases where a literal should check for an immediate operand,
instead of a register This avoids needing to invent a special way of
representing timm literal values.
Also handle immediate arguments in GIM_CheckLiteralInt. The comments
stated it handled isImm() and isCImm(), but that wasn't really true.
This unblocks work on the selection of all of the complicated AMDGPU
intrinsics in future commits.
The current implementation assumes there is an instruction associated
with the transform, but this is not the case for
timm/TargetConstant/immarg values. These transforms should directly
operate on a specific MachineOperand in the source
instruction. TableGen would assert if you attempted to define an
equivalent GISDNodeXFormEquiv using timm when it failed to find the
instruction matcher.
Specially recognize SDNodeXForms on timm, and pass the operand index
to the render function.
Ideally this would be a separate render function type that looks like
void renderFoo(MachineInstrBuilder, const MachineOperand&), but this
proved to be somewhat mechanically painful. Add an optional operand
index which will only be passed if the transform should only look at
the one source operand.
Theoretically it would also be possible to only ever pass the
MachineOperand, and the existing renderers would check the parent. I
think that would be somewhat ugly for the standard usage which may
want to inspect other operands, and I also think MachineOperand should
eventually not carry a pointer to the parent instruction.
Use it in one sample pattern. This isn't a great example, since the
transform exists to satisfy DAG type constraints. This could also be
avoided by just changing the MachineInstr's arbitrary choice of
operand type from i16 to i32. Other patterns have nontrivial uses, but
this serves as the simplest example.
One flaw this still has is if you try to use an SDNodeXForm defined
for imm, but the source pattern uses timm, you still see the "Failed
to lookup instruction" assert. However, there is now a way to avoid
it.
Summary:
GIMatchTree's job is to build a decision tree by zipping all the
GIMatchDag's together.
Each DAG is added to the tree builder as a leaf and partitioners are used
to subdivide each node until there are no more partitioners to apply. At
this point, the code generator is responsible for testing any untested
predicates and following any unvisited traversals (there shouldn't be any
of the latter as the getVRegDef partitioner handles them all).
Note that the leaves don't always fit into partitions cleanly and the
partitions may overlap as a result. This is resolved by cloning the leaf
into every partition it belongs to. One example of this is a rule that can
match one of N opcodes. The leaf for this rule would end up in N partitions
when processed by the opcode partitioner. A similar example is the
getVRegDef partitioner where having rules (add $a, $b), and (add ($a, $b), $c)
will result in the former being in the partition for successfully
following the vreg-def and failing to do so as it doesn't care which
happens.
Depends on D69151
Fixed the issues with the windows bots which were caused by stdout/stderr
interleaving.
Reviewers: bogner, volkan
Reviewed By: volkan
Subscribers: lkail, mgorny, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69152
Copy the logic from the existing handling in the DAG matcher emittter.
This will enable some AMDGPU pattern cleanups without breaking
GlobalISel tests, and eventually handle importing more patterns.
The test is a bit annoying since the sections seem to randomly sort
themselves if anything else is added in the future.
All the windows bots are failing match-tree.td and there's no obvious cause that
I can see. It's not just the %p formatting problem. My best guess is that
there's an ordering issue too but I'll need further information to figure that
out. Revert while I'm investigating.
This reverts commit 64f1bb5cd2 and 77d4b5f5fe
Summary:
GIMatchTree's job is to build a decision tree by zipping all the
GIMatchDag's together.
Each DAG is added to the tree builder as a leaf and partitioners are used
to subdivide each node until there are no more partitioners to apply. At
this point, the code generator is responsible for testing any untested
predicates and following any unvisited traversals (there shouldn't be any
of the latter as the getVRegDef partitioner handles them all).
Note that the leaves don't always fit into partitions cleanly and the
partitions may overlap as a result. This is resolved by cloning the leaf
into every partition it belongs to. One example of this is a rule that can
match one of N opcodes. The leaf for this rule would end up in N partitions
when processed by the opcode partitioner. A similar example is the
getVRegDef partitioner where having rules (add $a, $b), and (add ($a, $b), $c)
will result in the former being in the partition for successfully
following the vreg-def and failing to do so as it doesn't care which
happens.
Depends on D69151
Reviewers: bogner, volkan
Reviewed By: volkan
Subscribers: lkail, mgorny, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69152
This assumed a single pattern if there was a predicate. Relax this a
bit, and allow multiple patterns as long as they have the same class.
This was only broken for the DAG path. GlobalISel seems to have
handled this correctly already.
This reverts commit e62e760f29.
The issue @uweigand raised should have been fixed by iterating over the
vector that owns the operand list data instead of the FoldingSet.
The MSVC issue raised by @thakis should have been fixed by relaxing the
regexes a little. I don't have a Windows machine available to test that so
I tested it by using `perl -p -e 's/0x([0-9a-f]+)/\U\1\E/g' to convert the
output of %p to the windows style.
I've guessed at the issue @phosek raised as there wasn't enough information
to investigate it. What I think is happening on that bot is the -debug
option isn't available because the second stage build is a release build.
I'm not sure why other release-mode bots didn't report it though.
and follow-on patches.
This is breaking a few build bots and local builds with follow-up already
on the patch thread.
This reverts commits 390c8baa54 and
520e3d66e7.
Summary:
When we build the walk across these DAG's we need to be able to reach every node
from the roots. Flip and traversal edges (so that use->def becomes def->uses)
that make nodes unreachable. Note that early on we'll just error out on these
flipped edges as def->uses edges are more complicated to match due to their
one->many nature.
Depends on D69077
Reviewers: volkan, bogner
Subscribers: llvm-commits
Summary:
The MatchDag structure is a representation of the checks that need to be
performed and the dependencies that limit when they can happen.
There are two kinds of node in the MatchDag:
* Instrs - Represent a MachineInstr
* Predicates - Represent a check that needs to be performed (i.e. opcode, is register, same machine operand, etc.)
and two kinds of edges:
* (Traversal) Edges - Represent a register that can be traversed to find one instr from another
* Predicate Dependency Edges - Indicate that a predicate requires a piece of information to be tested.
For example, the matcher:
(match (MOV $t, $s),
(MOV $d, $t))
with MOV declared as an instruction of the form:
%dst = MOV %src1
becomes the following MatchDag with the following instruction nodes:
__anon0_0 // $t=getOperand(0), $s=getOperand(1)
__anon0_1 // $d=getOperand(0), $t=getOperand(1)
traversal edges:
__anon0_1[src1] --[t]--> __anon0_0[dst]
predicate nodes:
<<$mi.getOpcode() == MOV>>:$__anonpred0_2
<<$mi.getOpcode() == MOV>>:$__anonpred0_3
and predicate dependencies:
__anon0_0 ==> __anonpred0_2[mi]
__anon0_0 ==> __anonpred0_3[mi]
The result of this parse is currently unused but can be tested
using -gicombiner-stop-after-parse as done in parse-match-pattern.td. The
dump for testing includes a graphviz format dump to allow the rule to be
viewed visually.
Later on, these MatchDag's will be used to generate code and to build an
efficient decision tree.
Reviewers: volkan, bogner
Reviewed By: volkan
Subscribers: arsenm, mgorny, mgrang, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69077
This has two main effects:
- Optimizes debug info size by saving 221.86 MB of obj file size in a
Windows optimized+debug build of 'all'. This is 3.03% of 7,332.7MB of
object file size.
- Incremental step towards decoupling target intrinsics.
The enums are still compact, so adding and removing a single
target-specific intrinsic will trigger a rebuild of all of LLVM.
Assigning distinct target id spaces is potential future work.
Part of PR34259
Reviewers: efriedma, echristo, MaskRay
Reviewed By: echristo, MaskRay
Differential Revision: https://reviews.llvm.org/D71320
Summary:
These allow you to get and set the operator of a dag node, without
affecting its list of arguments.
`!getop` is slightly fiddly because in many contexts you need its
return value to have a static type more specific than 'any record'. It
works to say `!cast<BaseClass>(!getop(...))`, but it's cumbersome, so
I made `!getop` take an optional type suffix itself, so that can be
written as the shorter `!getop<BaseClass>(...)`.
Reviewers: hfinkel, nhaehnle
Reviewed By: nhaehnle
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D71191
This is not a new semantic feature. The syntax `(? 1, 2, 3)` was
disallowed by the parser in a dag //expression//, but there were
already ways to sneak a `?` into the operator field of a dag
//value//, e.g. by initializing it from a class template parameter
which is then set to `?` by the instantiating `def`.
This patch makes `?` in the operator slot syntactically legal, so it's
now easy to construct dags with an unset operator. Also, the semantics
of `!con` are relaxed so that it will allow a combination of set and
unset operator fields in the dag nodes it's concatenating, with the
restriction that all the operators that are //not// unset still have
to agree with each other.
Reviewers: hfinkel, nhaehnle
Reviewed By: hfinkel, nhaehnle
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D71195
This error was originally added a while(7 years) ago when
including multiple files was basically always an error. Tablegen
now has preprocessor support, which allows for building nice
c/c++ style include guards. With the current error being
reported, we unfortunately need to double guard when including
files:
* In user of MyFile.td
#ifndef MYFILE_TD
include MyFile.td
#endif
* In MyFile.td
#ifndef MYFILE_TD
#define MYFILE_TD
...
#endif
Differential Revision: https://reviews.llvm.org/D70410
If there is a dag node with a variable number of operands that has at
least N operands (for some non-negative N), and multiple patterns with
that node with different number of operands, we would drop the number of
operands check in patterns with N operands, presumably because it's
guaranteed in such case that none of the per-operand checks will access
the operand list out-of-bounds.
Except semantically the check is about having exactly N operands, not at
least N operands, and a backend might rely on it to disambiguate
different patterns.
In this patch we change the condition on emitting the number of operands
check from "the instruction is not guaranteed to have at least as many
operands as are checked by the pattern being matched" to "the
instruction is not guaranteed to have a specific number of operands".
We're relying (still) on the rest of the CodeGenPatterns mechanics to
validate that the pattern itself doesn't try to access more operands
than there is in the instruction in cases when the instruction does have
fixed number of operands, and on the machine verifier to validate at
runtime that particular MIs like that satisfy the constraint as well.
Reviewers: dsanders, qcolombet
Reviewed By: qcolombet
Subscribers: arsenm, rovka, Petar.Avramovic, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69653
Cullen Rhodes