PowerPC subtargets prior to Power9 use the 'legacy' itinerary way to
provide scheduling information. This patch re-writes the tablegen file
to define the scheduling information in the new SchedModel way, which
can bring improvements to some benchmarks.
Reviewed By: shchenz
Differential Revision: https://reviews.llvm.org/D154488
D141386 changed the semantics of !range metadata to return poison
on violation. If !range is combined with !noundef, violation is
immediate UB instead, matching the old semantics.
In theory, these IR semantics should also carry over into SDAG.
In practice, DAGCombine has at least one key transform that is
invalid in the presence of poison, namely the conversion of logical
and/or to bitwise and/or (c7b537bf09/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp (L11252)).
Ideally, we would fix this transform, but this will require
substantial work to avoid codegen regressions.
In the meantime, avoid transferring !range metadata without
!noundef, effectively restoring the old !range metadata semantics
on the SDAG layer.
Fixes https://github.com/llvm/llvm-project/issues/64589.
Differential Revision: https://reviews.llvm.org/D157685
No longer conservatively assume a load/store accesses the stack when we
can prove that we did not compute any stack-relative address up to this
point in the program.
We do this in a cheap not-quite-a-dataflow-analysis: Assume
`NoStackAddressUsed` when all predecessors of a block already guarantee
it. Process blocks in reverse post order to guarantee that except for
loop headers we have processed all predecessors of a block before
processing the block itself. For loops we accept the conservative answer
as they are unlikely to be shrink-wrappable anyway.
Differential Revision: https://reviews.llvm.org/D152213
Switch and update some tests to use `update_llc_test_checks` to reduce
clutter in upcoming change.
Differential Revision: https://reviews.llvm.org/D152215
The LIT test cases were migrated with the script provided by
Nikita Popov. Due to the size of the change it is split into
several parts.
Reviewed By: nemanja, amyk, nikic, PowerPC
Differential Revision: https://reviews.llvm.org/D135470
Summary:
Relate bug: https://bugs.llvm.org/show_bug.cgi?id=37472
The shrink wrapping pass prematurally restores the stack, at a point where the stack might still be accessed.
Taking an exception can cause the stack to be corrupted.
As a first approach, this patch is overly conservative, assuming that any instruction that may load or store could access
the stack.
Reviewers: dmgreen, qcolombet
Reviewed By: qcolombet
Subscribers: simpal01, efriedma, eli.friedman, javed.absar, llvm-commits, eugenis, chill, carwil, thegameg
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D63152
llvm-svn: 363265
Currently we have a number of tests that fail with -verify-machineinstrs.
To detect this cases earlier we add the option to the testcases with the
exception of tests that will currently fail with this option. PR 27456 keeps
track of this failures.
No code review, as discussed with Hal Finkel.
llvm-svn: 277624
