I'm not entirely sure this is the correct thing
to do with the global isel philosophy, but I think
this is necessary to handle how differently SGPRs
are used normally vs. from a condition.
For example, it makes sense to allow a copy
from a VGPR to an SGPR, but it makes no sense
to allow a copy from VGPRs to SGPRs used as
select mask.
This avoids regbankselecting strange code with
a truncate feeding directly into a condition field.
Now a copy is forced from sgpr(s1) to vcc, which is
more sensible to handle.
Some of these issues could probably avoided with making enough
operations resulting in i1 illegal. I think we can't avoid
this register bank for legality.
For example, an i1 and where one source is from a truncate, and
one source is a compare needs some kind of copy inserted to
make sure both are in condition registers.
llvm-svn: 350611
If a copy was needed to handle the condition of brcond, it was being
inserted before the defining instruction. Add tests for iterator edge
cases.
I find the existing code here suspect for the case where it's looking
for terminators that modify the register. It's going to insert a copy
in the middle of the terminators, which isn't allowed (it might be
necessary to have a COPY_terminator if anybody actually needs this).
Also legalize brcond for AMDGPU.
llvm-svn: 350595
This patch should not introduce any behavior changes. It consists of
mostly one of two changes:
1. Replacing fall through comments with the LLVM_FALLTHROUGH macro
2. Inserting 'break' before falling through into a case block consisting
of only 'break'.
We were already using this warning with GCC, but its warning behaves
slightly differently. In this patch, the following differences are
relevant:
1. GCC recognizes comments that say "fall through" as annotations, clang
doesn't
2. GCC doesn't warn on "case N: foo(); default: break;", clang does
3. GCC doesn't warn when the case contains a switch, but falls through
the outer case.
I will enable the warning separately in a follow-up patch so that it can
be cleanly reverted if necessary.
Reviewers: alexfh, rsmith, lattner, rtrieu, EricWF, bollu
Differential Revision: https://reviews.llvm.org/D53950
llvm-svn: 345882
Note a normal select test is not currently possible because this
relies on input registers tracked in SIMachineFunctionInfo which
are not currently serializable in MIR, but this does work end-to-end
from the IR.
llvm-svn: 335490
Summary:
MCTargetDesc/AMDGPUMCTargetDesc.h contains enums for all the instuction
and register defintions, which are huge so we only want to include
them where needed.
This will also make it easier if we want to split the R600 and GCN
definitions into separate tablegenerated files.
I was unable to remove AMDGPUMCTargetDesc.h from SIMachineFunctionInfo.h
because it uses some enums from the header to initialize default values
for the SIMachineFunction class, so I ended up having to remove includes of
SIMachineFunctionInfo.h from headers too.
Reviewers: arsenm, nhaehnle
Reviewed By: nhaehnle
Subscribers: MatzeB, kzhuravl, wdng, yaxunl, dstuttard, tpr, t-tye, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D46272
llvm-svn: 332930
