As older waves execute long sequences of VALU instructions, this may
prevent younger waves from address calculation and then issuing their
VMEM loads, which in turn leads the VALU unit to idle. This patch tries
to prevent this by temporarily raising the wave's priority.
Reviewed By: foad
Differential Revision: https://reviews.llvm.org/D124246
Add these bits to the MUBUF and FLAT LDS DMA instructions:
- LGKM_CNT - these operate on LDS;
- VALU - SPG 3.9.8: This instruction acts as both a MUBUF and
VALU instruction;
Codegen currently does not produce any of this, so the change is NFC.
Differential Revision: https://reviews.llvm.org/D124472
Image.sample instruction can be forced to return half type instead of
float when d16 flag is enabled.
This patch adds new pattern in InstCombine to detect if output of
image.sample is used later only by fptrunc which converts the type
from float to half. If pattern is detected then fptrunc and image.sample
are combined to single image.sample which is returning half type.
Later in Lowering part d16 flag is added to image sample intrinsic.
Differential Revision: https://reviews.llvm.org/D124232
The builtin predicate handling has a strange behavior where the code
assumes that a PatFrag is a stack of PatFrags, and each level adds at
most one predicate. I don't think this particularly makes sense,
especially without a diagnostic to ensure you aren't trying to set
multiple at once.
This wasn't followed for address spaces and alignment, which could
potentially fall through to report no builtin predicate was
added. Just switch these to follow the existing convention for now.
Currently metadata is inserted in a late pass which is lowered
to an AssertZext. The metadata would be more useful if it was
inserted earlier after inlining, but before codegen.
Probably shouldn't change anything now. Just replacing the
late metadata annotation needs more work, since we lose
out on optimizations after these are lowered to CopyFromReg.
Seems to be slightly better than relying on the AssertZext from the
metadata. The test change in cvt_f32_ubyte.ll is a quirk from it using
-start-before=amdgpu-isel instead of running the usual codegen
pipeline.
This is to avoid relying on the post-isel hook.
This change also enable the saddr pattern selection for atomic
intrinsics in GlobalISel.
Differential Revision: https://reviews.llvm.org/D123583
Here is the performance data:
```
Using platform: AMD Accelerated Parallel Processing
Using device: gfx900:xnack-
ds_write_b64 aligned by 8: 3.2 sec
ds_write2_b32 aligned by 8: 3.2 sec
ds_write_b16 * 4 aligned by 8: 7.0 sec
ds_write_b8 * 8 aligned by 8: 13.2 sec
ds_write_b64 aligned by 1: 7.3 sec
ds_write2_b32 aligned by 1: 7.5 sec
ds_write_b16 * 4 aligned by 1: 14.0 sec
ds_write_b8 * 8 aligned by 1: 13.2 sec
ds_write_b64 aligned by 2: 7.3 sec
ds_write2_b32 aligned by 2: 7.5 sec
ds_write_b16 * 4 aligned by 2: 7.1 sec
ds_write_b8 * 8 aligned by 2: 13.3 sec
ds_write_b64 aligned by 4: 4.6 sec
ds_write2_b32 aligned by 4: 3.2 sec
ds_write_b16 * 4 aligned by 4: 7.1 sec
ds_write_b8 * 8 aligned by 4: 13.3 sec
ds_read_b64 aligned by 8: 2.3 sec
ds_read2_b32 aligned by 8: 2.2 sec
ds_read_u16 * 4 aligned by 8: 4.8 sec
ds_read_u8 * 8 aligned by 8: 8.6 sec
ds_read_b64 aligned by 1: 4.4 sec
ds_read2_b32 aligned by 1: 7.3 sec
ds_read_u16 * 4 aligned by 1: 14.0 sec
ds_read_u8 * 8 aligned by 1: 8.7 sec
ds_read_b64 aligned by 2: 4.4 sec
ds_read2_b32 aligned by 2: 7.3 sec
ds_read_u16 * 4 aligned by 2: 4.8 sec
ds_read_u8 * 8 aligned by 2: 8.7 sec
ds_read_b64 aligned by 4: 4.4 sec
ds_read2_b32 aligned by 4: 2.3 sec
ds_read_u16 * 4 aligned by 4: 4.8 sec
ds_read_u8 * 8 aligned by 4: 8.7 sec
Using platform: AMD Accelerated Parallel Processing
Using device: gfx1030
ds_write_b64 aligned by 8: 4.4 sec
ds_write2_b32 aligned by 8: 4.3 sec
ds_write_b16 * 4 aligned by 8: 7.9 sec
ds_write_b8 * 8 aligned by 8: 13.0 sec
ds_write_b64 aligned by 1: 23.2 sec
ds_write2_b32 aligned by 1: 23.1 sec
ds_write_b16 * 4 aligned by 1: 44.0 sec
ds_write_b8 * 8 aligned by 1: 13.0 sec
ds_write_b64 aligned by 2: 23.2 sec
ds_write2_b32 aligned by 2: 23.1 sec
ds_write_b16 * 4 aligned by 2: 7.9 sec
ds_write_b8 * 8 aligned by 2: 13.1 sec
ds_write_b64 aligned by 4: 13.5 sec
ds_write2_b32 aligned by 4: 4.3 sec
ds_write_b16 * 4 aligned by 4: 7.9 sec
ds_write_b8 * 8 aligned by 4: 13.1 sec
ds_read_b64 aligned by 8: 3.5 sec
ds_read2_b32 aligned by 8: 3.4 sec
ds_read_u16 * 4 aligned by 8: 5.3 sec
ds_read_u8 * 8 aligned by 8: 8.5 sec
ds_read_b64 aligned by 1: 13.1 sec
ds_read2_b32 aligned by 1: 22.7 sec
ds_read_u16 * 4 aligned by 1: 43.9 sec
ds_read_u8 * 8 aligned by 1: 7.9 sec
ds_read_b64 aligned by 2: 13.1 sec
ds_read2_b32 aligned by 2: 22.7 sec
ds_read_u16 * 4 aligned by 2: 5.6 sec
ds_read_u8 * 8 aligned by 2: 7.9 sec
ds_read_b64 aligned by 4: 13.1 sec
ds_read2_b32 aligned by 4: 3.4 sec
ds_read_u16 * 4 aligned by 4: 5.6 sec
ds_read_u8 * 8 aligned by 4: 7.9 sec
```
GFX10 exposes a different pattern for sub-DWORD load/store performance
than GFX9. On GFX9 it is faster to issue a single unaligned load or
store than a fully split b8 access, where on GFX10 even a full split
is better. However, this is a theoretical only gain because splitting
an access to a sub-dword level will require more registers and packing/
unpacking logic, so ignoring this option it is better to use a single
64 bit instruction on a misaligned data with the exception of 4 byte
aligned data where ds_read2_b32/ds_write2_b32 is better.
Differential Revision: https://reviews.llvm.org/D123956
Fix isVCC for register that was assigned register class during
inst-selection. This happens when register has multiple uses.
For wave32, uniform i1 to vcc copy was selected like vcc to vcc
copy when uniform i1 had assigned register class.
Uniform i1 register with assigned register class will have s1 LLT,
be defined using G_TRUNC and class will be SReg_32RegClass.
Vcc i1 register with assigned register class will have s1 LLT,
class will be SReg_32RegClass for wave32 and SReg_64RegClass for
wave64 and register will not be defined by G_TRUNC.
Differential Revision: https://reviews.llvm.org/D124163
This fixes the assertion failure "Loop in the Block Graph!".
SIMachineScheduler groups instructions into blocks (also referred to
as coloring or groups) and then performs a two-level scheduling:
inter-block scheduling, and intra-block scheduling.
This approach requires that the dependency graph on the blocks which
is obtained by contracting the blocks in the original dependency graph
is acyclic. In other words: Whenever A and B end up in the same block,
all vertices on a path from A to B must be in the same block.
When compiling an example consisting of an export followed by
a buffer store, we see a dependency between these two. This dependency
may be false, but that is a different issue.
This dependency was not correctly accounted for by SiMachineScheduler.
A new test case si-scheduler-exports.ll demonstrating this is
also added in this commit.
The problematic part of SiMachineScheduler was a post-optimization of
the block assignment that tried to group all export instructions into
a separate export block for better execution performance. This routine
correctly checked that any paths from exports to exports did not
contain any non-exports, but not vice-versa: In case of an export with
a non-export successor dependency, that single export was moved
to a separate block, which could then be both a successor and a
predecessor block of a non-export block.
As fix, we now skip export grouping if there are exports with direct
non-export successor dependencies. This fixes the issue at hand,
but is slightly pessimistic:
We *could* group all exports into a separate block that have neither
direct nor indirect export successor dependencies.
We will review the potential performance impact and potentially
revisit with a more sophisticated implementation.
Note that just grouping all exports without direct non-export successor
dependencies could still lead to illegal blocks, since non-export A
could depend on export B that depends on export C. In that case,
export C has no non-export successor, but still may not be grouped
into an export block.
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
When folding a COPY of exec into another COPY, the call to
TII->isOperandLegal would crash because COPYs don't have defined
register classes for their operands.
Differential Revision: https://reviews.llvm.org/D122737
These don't seem to be very well used or tested, but try to make the
behavior a bit more consistent with LDS globals.
I'm not sure what the definition for amdgpu-gds-size is supposed to
mean. For now I assumed it's allocating a static size at the beginning
of the allocation, and any known globals are allocated after it.
There's no reason to create these immediately. They can be created in
the prolog/epilog code like CSR spills. There's probably a cleaner way
to do this by utilizing the CSR spill code.
This makes the frame index used transient state for
PrologEpilogInserter, and thus makes serialization easier. Really this
doesn't need to be saved here but there isn't really a better place
for it.
The sramecc feature changes the behaviour of d16 loads so they do not
preserve the unused 16 bits of the result register, but it has no impact
on d16 stores, so we should make use of them even when the feature is
enabled.
Differential Revision: https://reviews.llvm.org/D104912
Instead of lengthy constructors we can now set the members of a
read-only struct before the Attributor is created. Should make it
clearer what is configurable and also help introducing new options in
the future. This actually added IsModulePass and avoids deduction
through the Function set size. No functional change was intended.
This is an NFC patch in preparation to fix a bug related to always
reserving VGPR32 for AGPR copy.
Reviewed By: rampitec
Differential Revision: https://reviews.llvm.org/D123651