Use this to remove a linear scan from CodeGenProcModel::hasReadOfWrite.
This reduces build time of RISCVGenSubtargetInfo.inc on by machine from
~6 seconds to ~3 seconds.
2 of the 3 callers of each of these already had a reference they
converted to index. Use that reference and make the one caller
that only has an index responsible for looking up the reference from it.
Use this to improve performance of SubtargetEmitter::findWriteResources
and SubtargetEmitter::findReadAdvance. Now we can do a map lookup
instead of a linear search through all WriteRes/ReadAdvance records.
This reduces the build time of RISCVGenSubtargetInfo.inc on my
machine from 43 seconds to 10 seconds.
The function called find_if and converted the iterator to an index.
The caller then had to check the index being non-zero to know if the
find succeeded.
Seems better to just do the find and distance in the caller.
This partially reverts commit 07ff786e39e2190449998d3af1000454dee501be.
The hunk being reverted in this patch seems to break:
tools/llvm-gsymutil/ARM_AArch64/macho-merged-funcs-dwarf.yaml
under LLVM_ENABLE_EXPENSIVE_CHECKS.
- Refactor SetTheory code to use const pointers when possible.
- Use auto for variables initialized using dyn_cast<>.
- Use range based for loops and early continue.
- Extract code for sorting and checking duplicate Records into a helper
function and update `collectProcModels` to use the helper.
- Update `FeatureKeyValues` to:
(a) Remove code for duplicate checks and use the helper.
(b) Trim features with empty name explicitly to be able to use
the helper.
- Make the sorting deterministic by using record name as a secondary
key for sorting, and re-enable SubtargetFeatureUniqueNames.td test
that was disabled due to the non-determinism of the error messages.
- Change wording of error message when duplicate records are found to
be source code position agnostic, since `First` may not be before
`Second` lexically.
SubtargetEmitter::GenSchedClassTables takes a CodeGenProcModel, but
calls hasReadOfWrite which loops over all ProcModels. We move
hasReadOfWrite to CodeGenProcModel and remove the loop over all
ProcModels. This leads to a 144% speedup on the RISC-V backend of our
downstream.
Refactor of the llvm-tblgen source into:
- a "Basic" library, which contains the bare minimum utilities to build
`llvm-min-tablegen`
- a "Common" library which contains all of the helpers for TableGen
backends. Such helpers can be shared by more than one backend, and even
unit tested (e.g. CodeExpander is, maybe we can add more over time)
Fixes#80647
