12 Commits

Author SHA1 Message Date
hsmahesha
5bd87350a5 [AMDGPU] On gfx908, reserve VGPR for AGPR copy based on register budget.
Based on available register budget, reserve highest available VGPR for
AGPR copy before RA. After RA, shift it to lowest unused VGPR if the one
exist.

Fixes SWDEV-330006.

Reviewed By: rampitec

Differential Revision: https://reviews.llvm.org/D123525
2022-04-21 07:57:26 +05:30
Matt Arsenault
f2c99ea47d AMDGPU: Use reserved VGPR for AGPR spills to memory
Previously would reuse the VGPR used for large frame offsets with the
one needed for copying from the AGPR. Fix this by reusing the register
we already reserved for handling AGPR to AGPR copies.
2022-02-08 11:26:59 -05:00
Stanislav Mekhanoshin
dbf278b984 [AMDGPU] Prevent aliasing of SrcC and Dst in MAI
Form the MAI spec: It’s ok that Src_C and vDst are the exact same VGPRs
or Src_C and vDst are completely separated. The case that Src_C and vDst
are overlapping should be avoid as new value could be written to accumulator
input before it gets read.

Note that this inevitably increases register pressure to the point where
some programs will become uncompilable.

This patch separates MAC and FMA versions of MFMA instructions using either
tied dst and src2 or earlyclobber dst.

Fixes: SWDEV-318900

Differential Revision: https://reviews.llvm.org/D117844
2022-01-26 14:48:20 -08:00
Christudasan Devadasan
cf58b9ce98 [AMDGPU] Add AV class spill pseudo instructions
While enabling vector superclasses with D109301,
the AV spills are converted into VGPR spills by
introducing appropriate copies. The whole thing
ended up adding two instructions per spill (a copy
+ vgpr spill pseudo) and caused an incorrect
liverange update during inline spiller.

This patch adds the pseudo instructions for all
AV spills from 32b to 1024b and handles them in
the way all other spills are lowered.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D115439
2021-12-10 03:10:34 -05:00
Christudasan Devadasan
5297cbf045 [AMDGPU] Enable copy between VGPR and AGPR classes during regalloc
Greedy register allocator prefers to move a constrained
live range into a larger allocatable class over spilling
them. This patch defines the necessary superclasses for
vector registers. For subtargets that support copy between
VGPRs and AGPRs, the vector register spills during regalloc
now become just copies.

Reviewed By: rampitec, arsenm

Differential Revision: https://reviews.llvm.org/D109301
2021-11-29 22:19:33 -05:00
Stanislav Mekhanoshin
a8d9d50762 [AMDGPU] gfx90a support
Differential Revision: https://reviews.llvm.org/D96906
2021-02-17 16:01:32 -08:00
Stanislav Mekhanoshin
dd89249498 [AMDGPU] Annotate vgpr<->agpr spills in asm
Differential Revision: https://reviews.llvm.org/D92125
2020-12-07 11:25:25 -08:00
Matt Arsenault
d2e74fad20 AMDGPU: Set more mov flags on V_ACCVGPR_{READ|WRITE}_B32
This fixes extra copies when materializing constants in AGPRs. This
made it a lot harder to trigger the spilling in spill-agpr.ll
2020-07-01 18:58:59 -04:00
Matt Arsenault
cdd3054255 AMDGPU: Fix a test to be more stable
The chained unconditional branches can be eliminated and it's not
relevant to the test.
2020-06-02 13:47:48 -04:00
Scott Linder
60b1967c39 [AMDGPU] Add Scratch Wave Offset to Scratch Buffer Descriptor in entry functions
Add the scratch wave offset to the scratch buffer descriptor (SRSrc) in
the entry function prologue. This allows us to removes the scratch wave
offset register from the calling convention ABI.

As part of this change, allow the use of an inline constant zero for the
SOffset of MUBUF instructions accessing the stack in entry functions
when a frame pointer is not requested/required. Entry functions with
calls still need to set up the calling convention ABI stack pointer
register, and reference it in order to address arguments of called
functions. The ABI stack pointer register remains unswizzled, but is now
wave-relative instead of queue-relative.

Non-entry functions also use an inline constant zero SOffset for
wave-relative scratch access, but continue to use the stack and frame
pointers as before. When the stack or frame pointer is converted to a
swizzled offset it is now scaled directly, as the scratch wave offset no
longer needs to be subtracted first.

Update llvm/docs/AMDGPUUsage.rst to reflect these changes to the calling
convention.

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D75138
2020-03-19 15:35:16 -04:00
Stanislav Mekhanoshin
1dfae6fe50 [AMDGPU] use v32f32 for 3 mfma intrinsics
These should really use v32f32, but were defined as v32i32
due to the lack of the v32f32 type.

Differential Revision: https://reviews.llvm.org/D64667

llvm-svn: 365972
2019-07-12 22:42:01 +00:00
Stanislav Mekhanoshin
937ff6e701 [AMDGPU] gfx908 agpr spilling
Differential Revision: https://reviews.llvm.org/D64594

llvm-svn: 365833
2019-07-11 21:54:13 +00:00