Commit Graph

11 Commits

Author SHA1 Message Date
Fangrui Song de9d80c1c5 [llvm] LLVM_FALLTHROUGH => [[fallthrough]]. NFC
With C++17 there is no Clang pedantic warning or MSVC C5051.
2022-08-08 11:24:15 -07:00
Alex Richardson 35bf23e965 Avoid shuffle self-assignment in EXPENSIVE_CHECKS builds
Some versions of libstdc++ perform self-assignment in std::shuffle. This
breaks the EXPENSIVE_CHECKS builds of TableGen due to an incorrect assertion
in libstdc++.

See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85828.

Fixes https://llvm.org/PR37652

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D98167
2021-03-10 11:17:34 +00:00
Qiu Chaofan 9d2f06445f [llvm-exegesis] Ignore instructions using custom inserter
Some instructions defined in table-gen files sets usesCustomInserter
bit, which means it has to be lowered by target code and isn't actually
valid instruction at MC level. So we should treat them like pseudo
instructions.

Reviewed By: gchatelet

Differential Revision: https://reviews.llvm.org/D94898
2021-02-19 17:04:27 +08:00
Clement Courbet 24bf8faabd [llvm-exegesis] Do not try to assign random registers twice.
Doing a random assignment assigns both tested (forward) and back-to-back
(backward) instructions.

When none of the tested instruction and back-to-back instruction have
implicit aliasing, we're currently trying to do a random register
asignment twice.

Fix this (see PR26418).

Differential Revision: https://reviews.llvm.org/D90380
2020-10-29 13:27:35 +01:00
Roman Lebedev 6030fe01f4
[llvm-exegesis] Exploring X86::OperandType::OPERAND_COND_CODE
Summary:
Currently, we only have nice exploration for LEA instruction,
while for the rest, we rely on `randomizeUnsetVariables()`
to sometimes generate something interesting.
While that works, it isn't very reliable in coverage :)

Here, i'm making an assumption that while we may want to explore
multi-instruction configs, we are most interested in the
characteristics of the main instruction we were asked about.

Which we can do, by taking the existing `randomizeMCOperand()`,
and turning it on it's head - instead of relying on it to randomly fill
one of the interesting values, let's pregenerate all the possible interesting
values for the variable, and then generate as much `InstructionTemplate`
combinations of these possible values for variables as needed/possible.

Of course, that requires invasive changes to no longer pass just the
naked `Instruction`, but sometimes partially filled `InstructionTemplate`.

As it can be seen from the test, this allows us to explore
`X86::OperandType::OPERAND_COND_CODE` for instructions
that take such an operand.
I'm hoping this will greatly simplify exploration.

Reviewers: courbet, gchatelet

Reviewed By: gchatelet

Subscribers: orodley, mgorny, sdardis, tschuett, jrtc27, atanasyan, mstojanovic, andreadb, RKSimon, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D74156
2020-02-12 21:33:52 +03:00
Bill Wendling c55cf4afa9 Revert "Remove redundant "std::move"s in return statements"
The build failed with

  error: call to deleted constructor of 'llvm::Error'

errors.

This reverts commit 1c2241a793.
2020-02-10 07:07:40 -08:00
Bill Wendling 1c2241a793 Remove redundant "std::move"s in return statements 2020-02-10 06:39:44 -08:00
Benjamin Kramer adcd026838 Make llvm::StringRef to std::string conversions explicit.
This is how it should've been and brings it more in line with
std::string_view. There should be no functional change here.

This is mostly mechanical from a custom clang-tidy check, with a lot of
manual fixups. It uncovers a lot of minor inefficiencies.

This doesn't actually modify StringRef yet, I'll do that in a follow-up.
2020-01-28 23:25:25 +01:00
Miloš Stojanović e8fc8507da [llvm-exegesis] Don't use unsupported aliasing instructions
Since some instruction types aren't allowed as the main instruction also
don't allow them for aliasing instructions.

Differential Revision: https://reviews.llvm.org/D73220
2020-01-23 12:42:42 +01:00
Clement Courbet 6d2510d30a [llvm-exegesis] Restrict to allowed back-to-back instructions in SerialSnippetGenerator.
Summary: Followup to D73161.

Reviewers: gchatelet, mstojanovic

Subscribers: tschuett, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73256
2020-01-23 10:00:05 +01:00
Miloš Stojanović 24b7b99b7d [llvm-exegesis][NFC] Disassociate snippet generators from benchmark runners
The addition of `inverse_throughput` mode highlighted the disjointedness
of snippet generators and benchmark runners because it used the
`UopsSnippetGenerator` with the  `LatencyBenchmarkRunner`.
To keep the code consistent tie the snippet generators to
parallelization/serialization rather than their benchmark runners.

Renaming `LatencySnippetGenerator` -> `SerialSnippetGenerator`.
Renaming `UopsSnippetGenerator` -> `ParallelSnippetGenerator`.

Differential Revision: https://reviews.llvm.org/D72928
2020-01-20 16:19:13 +01:00