Commit Graph

9 Commits

Author SHA1 Message Date
Matt Arsenault 79f67cae91 AMDGPU: Rename add/sub with carry out instructions
The hardware has created a real mess in the naming for add/sub, which
have been renamed basically every generation. Switch the carry out
pseudos to have the gfx9/gfx10 names. We were using the original SI/CI
v_add_i32/v_sub_i32 names. Later targets reintroduced these names as
carryless instructions with a saturating clamp bit, which we do not
define. Do this rename so we can unambiguously add these missing
instructions.

The carry-in versions should also be renamed, but at least those had a
consistent _u32 name to begin with. The 16-bit instructions were also
renamed, but aren't ambiguous.

This does regress assembler error message quality in some cases. In
mismatched wave32/wave64 situations, this will switch from
"unsupported instruction" to "invalid operand", with the error
pointing at the wrong position. I couldn't quite follow how the
assembler selects these, but the previous behavior seemed accidental
to me. It looked like there was a partial attempt to handle this which
was never completed (i.e. there is an AMDGPUOperand::isBoolReg but it
isn't used for anything).
2020-07-16 13:16:30 -04:00
Matt Arsenault 62129878a6 AMDGPU/GlobalISel: Fix tablegen selection for scalar bin ops
Fixes selection for scalar G_SMULH/G_UMULH. Also switches to using
tablegen selected add/sub, which switch to the signed version of the
opcode. This matches the current DAG behavior. We can't drop the
manual selection for add/sub yet, because it's still both for VALU
add/sub and for G_PTR_ADD.
2020-01-29 08:55:54 -08:00
Matt Arsenault 618fa77ae4 AMDGPU/GlobalISel: Select V_ADD3_U32/V_XOR3_B32
The other 3-op patterns should also be theoretically handled, but
currently there's a bug in the inferred pattern complexity.

I'm not sure what the error handling strategy should be for potential
constant bus violations. I think the correct strategy is to never
produce mixed SGPR and VGPR operands in a typical VOP instruction,
which will trivially avoid them. However, it's possible to still have
hand written MIR (or erroneously transformed code) with these
operands. When these fold, the restriction will be violated. We
currently don't have any verifiers for reg bank legality. For now,
just ignore the restriction.

It might be worth triggering a DAG fallback on verifier error.
2020-01-23 12:04:20 -05:00
Matt Arsenault 3952748ffd AMDGPU/GlobalISel: Fix add of neg inline constant pattern 2020-01-09 10:29:31 -05:00
Matt Arsenault f9a42ed0a7 AMDGPU: Relax 32-bit SGPR register class
Mostly use SReg_32 instead of SReg_32_XM0 for arbitrary values. This
will allow the register coalescer to do a better job eliminating
copies to m0.

For GlobalISel, as a terrible hack, use SGPR_32 for things that should
use SCC until booleans are solved.

llvm-svn: 375267
2019-10-18 18:26:37 +00:00
Matt Arsenault fdd761af15 AMDGPU/GlobalISel: Prepare some tests for store selection
Mostsly these would fail due to trying to use SI with a flat
operation. Implementing global loads with MUBUF is more work than
flat, so these won't be handled in the initial load selection.

Others fail because store of s64 won't initially work, as the current
set of patterns expect everything to be turned into v2i32.

llvm-svn: 365493
2019-07-09 14:30:57 +00:00
Matt Arsenault 0a52e9d026 AMDGPU/GlobalISel: Complete implementation of G_GEP
Also works around tablegen defect in selecting add with unused carry,
but if we have to manually select GEP, might as well handle add
manually.

llvm-svn: 364806
2019-07-01 16:34:48 +00:00
Matt Arsenault d810ff2588 AMDGPU/GlobalISel: Try to select VOP3 form of add
There are several things broken, but at least emit the right thing for
gfx9.

The import of the pattern with the unused carry out seems to not
work. Needs a special class for clamp, because OperandWithDefaultOps
doesn't really work.

llvm-svn: 364804
2019-07-01 16:27:32 +00:00
Tom Stellard 9e9dd30de3 AMDGPU/GlobalISel: Implement select for 32-bit G_ADD
Reviewers: arsenm

Reviewed By: arsenm

Subscribers: hiraditya, kzhuravl, jvesely, wdng, nhaehnle, yaxunl, rovka, kristof.beyls, dstuttard, tpr, t-tye, Petar.Avramovic, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58804

llvm-svn: 364797
2019-07-01 16:09:33 +00:00