Summary:
Predicate<> now has a field to indicate how often it must be recomputed.
Currently, there are two frequencies, per-module (RecomputePerFunction==0)
and per-function (RecomputePerFunction==1). Per-function predicates are
currently recomputed more frequently than necessary since the only predicate
in this category is cheap to test. Per-module predicates are now computed in
getSubtargetImpl() while per-function predicates are computed in selectImpl().
Tablegen now manages the PredicateBitset internally. It should only be
necessary to add the required includes.
Also fixed a problem revealed by the test case where
constrainSelectedInstRegOperands() would attempt to tie operands that
BuildMI had already tied.
Reviewers: ab, qcolombet, t.p.northover, rovka, aditya_nandakumar
Reviewed By: rovka
Subscribers: kristof.beyls, igorb, llvm-commits
Differential Revision: https://reviews.llvm.org/D32491
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301750 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Lift the restrictions that prevented the tree walking introduced in the
previous change and add support for patterns like:
(G_ADD (G_MUL (G_SEXT $src1), (G_SEXT $src2)), $src3) -> SMADDWrrr $dst, $src1, $src2, $src3
Also adds support for G_SEXT and G_ZEXT to support these cases.
One particular aspect of this that I should draw attention to is that I've
tried to be overly conservative in determining the safety of matches that
involve non-adjacent instructions and multiple basic blocks. This is intended
to be used as a cheap initial check and we may add a more expensive check in
the future. The current rules are:
* Reject if any instruction may load/store (we'd need to check for intervening
memory operations.
* Reject if any instruction has implicit operands.
* Reject if any instruction has unmodelled side-effects.
See isObviouslySafeToFold().
Reviewers: t.p.northover, javed.absar, qcolombet, aditya_nandakumar, ab, rovka
Reviewed By: ab
Subscribers: igorb, dberris, llvm-commits, kristof.beyls
Differential Revision: https://reviews.llvm.org/D30539
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299430 91177308-0d34-0410-b5e6-96231b3b80d8
Move the logic to constraint register from InstructionSelector to a
utility function. It will be required by other passes in the GlobalISel
pipeline.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@290374 91177308-0d34-0410-b5e6-96231b3b80d8
Add the minimal support necessary to select a function that returns the sum of
two i32 values.
This includes some support for argument/return lowering of i32 values through
registers, as well as the handling of copy and add instructions throughout the
GlobalISel pipeline.
Differential Revision: https://reviews.llvm.org/D26677
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289940 91177308-0d34-0410-b5e6-96231b3b80d8
Mostly straightforward as we ignore addressing modes and just
use the base + unsigned immediate offset (always 0) variants.
This currently fails to select extloads because we have yet to
agree on a representation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277171 91177308-0d34-0410-b5e6-96231b3b80d8
