This improves type safety and is less verbose. Use SimpleTy only where
an integer is needed like switches or emitting a VBR.
---------
Co-authored-by: Sergei Barannikov <barannikov88@gmail.com>
Teach `SDNodeInfoEmitter` TableGen backend to process `SDTypeConstraint`
records and emit tables for them. The tables are used by
`SDNodeInfo::verifyNode()` to validate a node being created.
This PR only adds validation code for `SDTCisVT` and `SDTCVecEltisVT`
constraints to keep it smaller.
Pull Request: https://github.com/llvm/llvm-project/pull/150125
This mainly transitions the LLVM intrinsic string table from character
emission to string literal emission, which I confirmed happens for me
locally.
I moved the guts of StringToOffsetTable to a cpp file so I could move
the `EmitLongStrLiterals` cl::opt global to a non-vague linkage home in
the `TableGen` library. I had to add missing FormatVariadic.h includes
to account for moving other includes to a cpp file.
Historically, the main example of *very* large string tables used the
`EmitCharArray` to work around MSVC limitations with string literals,
but that was switched (without removing the API) in order to consolidate
on a nicer emission primitive.
While this large string table in `IntrinsicsImpl.inc` seems to compile
correctly on MSVC without the work around in `EmitCharArray` (and that
this PR adds back to the nicer emission path), other users have
repeatedly hit this MSVC limitation as you can see in the discussion on
PR https://github.com/llvm/llvm-project/pull/120534. This PR teaches the
string offset table emission to look at
the size of the table and switch to the char array emission strategy
when the table becomes too large.
This work around does have the downside of making compile times worse
for large string tables, but that appears unavoidable until we can
identify known good MSVC versions and switch to requiring them for all
LLVM users. It also reduces searchability of the generated string table
-- I looked at emitting a comment with each string but it is tricky
because the escaping rules for an inline comment are different from
those of of a string literal, and there's no real way to turn the string
literal into a comment.
While improving the output in this way, also clean up the output to not
emit an extraneous empty string at the end of the string table, and
update the `StringTable` class to not look for that. It isn't actually
used by anything and is wasteful.
This PR also switches the `IntrinsicsImpl.inc` string tables over to the
new `StringTable` runtime abstraction. I didn't want to do this until
landing the MSVC workaround in case it caused even this example to start
hitting the MSVC bug, but I wanted to switch here so that I could
simplify the API for emitting the string table with the workaround
present. With the two different emission strategies, its important to
use a very exact syntax and that seems better encapsulated in the API.
Last but not least, the `SDNodeInfoEmitter` is updated, including its
tests to match the new output.
This PR should unblock landing
https://github.com/llvm/llvm-project/pull/120534 and letting us switch
all of
Clang's builtins to use string tables. That PR has all the details
motivating the overall effort.
Follow-up patches will try to consolidate the remaining users onto the
single interface, but those at least were easy to separate into
follow-ups and keep this PR somewhat smaller.
This patch adds a simplistic backend that gathers all target-specific
SelectionDAG nodes and emits descriptions for most of them.
This includes generating node enumeration, node names, and information
about node "prototype" that can be used to verify that a node is valid.
The patch also extends SDNode by adding target-specific flags, which are
also included in the generated tables.
Part of #119709,
[RFC](https://discourse.llvm.org/t/rfc-tablegen-erating-sdnode-descriptions/83627).
Pull Request: https://github.com/llvm/llvm-project/pull/123002
