Discussed here:
http://lists.llvm.org/pipermail/llvm-dev/2018-January/120320.html
In preparation for adding support for named vregs we are changing the sigil for
physical registers in MIR to '$' from '%'. This will prevent name clashes of
named physical register with named vregs.
llvm-svn: 323922
https://reviews.llvm.org/D42402
A lot of these copies are useless (copies b/w VRegs having the same
regclass) and should be cleaned up.
llvm-svn: 323291
Summary:
Print %subreg.<subregidxname> instead of just the subregister
index when printing immediate operands corresponding to subreg
indices in INSERT_SUBREG, EXTRACT_SUBREG, SUBREG_TO_REG and
REG_SEQUENCE.
Reviewers: qcolombet, MatzeB
Reviewed By: MatzeB
Subscribers: nhaehnle, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D39696
llvm-svn: 317513
This updates the MIRPrinter to include the regclass when printing
virtual register defs, which is already valid syntax for the
parser. That is, given 64 bit %0 and %1 in a "gpr" regbank,
%1(s64) = COPY %0(s64)
would now be written as
%1:gpr(s64) = COPY %0(s64)
While this change alone introduces a bit of redundancy with the
registers block, it allows us to update the tests to be more concise
and understandable and brings us closer to being able to remove the
registers block completely.
Note: We generally only print the class in defs, but there is one
exception. If there are uses without any defs whatsoever, we'll print
the class on all uses. I'm not completely convinced this comes up in
meaningful machine IR, but for now the MIRParser and MachineVerifier
both accept that kind of stuff, so we don't want to have a situation
where we can print something we can't parse.
llvm-svn: 316479
This is in preparation for a verifier check that makes sure copies are
of the same size (when generic virtual registers are involved).
llvm-svn: 316387
This runs `udpate_mir_test_checks --add-vreg-checks` on the tests taht
are already more or less in the format that generates, so that there
will be less churn in some upcoming changes.
llvm-svn: 316139
If -simplify-mir option is passed then MIRPrinter will not print such fields.
This change also required some lit test cases in CodeGen directory to be changed.
Reviewed By: MatzeB
Differential Revision: https://reviews.llvm.org/D32304
llvm-svn: 304779
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
llvm-svn: 299430
Folding instructions when selecting can cause them to become dead.
Don't select these dead instructions (if they don't have other side
effects, and don't define physical registers).
Preserve existing tests by adding COPYs.
In some tests, the G_CONSTANT vregs never get constrained to a class:
the only use of the vreg was folded into another instruction, so the
G_CONSTANT, now dead, never gets selected.
llvm-svn: 298224
And remove some redundant bitcast tests.
Also split the test functions themselves: it makes it obvious to see
what's tested where and what isn't, it makes the tests much easier to
read and manually update, and, most importantly, it makes them almost
trivial to update using tooling. Yes, it's obnoxiously verbose, but
said tooling helps upgrade to better MIR syntax whenever available.
llvm-svn: 298222