If we have an instruction where more than one pointer operands
are derived from the same promoted alloca, we are fixing it for
one argument and do not fix a second use considering this user
done.
Fix this by deferring processing of memory intrinsics until all
potential operands are replaced.
Fixes: SWDEV-271358
Differential Revision: https://reviews.llvm.org/D96386
Fixes a testcase that was overcommitting large register tuples to a
bundle, which the register allocator could not possibly satisfy. This
was producing a bundle which used nearly all of the available SGPRs
with a series of 16-dword loads (not all of which are freely available
to use).
This is a quick hack for some deeper issues with how the clause
bundler tracks register pressure.
Overall the pressure tracking used here doesn't make sense and is too
imprecise for what it needs to avoid the allocator failing. The
pressure estimate does not account for the alignment requirements of
large SGPR tuples, so this was really underestimating the pressure
impact. This also ignores the impact of the extended live range of the
use registers after the bundle is introduced. Additionally, it didn't
account for some wide tuples not being available due to reserved
registers.
This regresses a few cases. These end up introducing more
spilling. This is also a function of the global pressure being used in
the decision to bundle, not the local pressure impact of the bundle
itself.
When merging a pair of DS reads or writes needs to materialize the base
offset in a vgpr, choose a value that is aligned to as high a power of
two as possible. This maximises the chance that different pairs can use
the same base offset, in which case the base offset registers can be
commoned up by MachineCSE.
Differential Revision: https://reviews.llvm.org/D96421
Move implementation of kill intrinsics to WQM pass. Add live lane
tracking by updating a stored exec mask when lanes are killed.
Use live lane tracking to enable early termination of shader
at any point in control flow.
Reviewed By: piotr
Differential Revision: https://reviews.llvm.org/D94746
We need to avoid setting the kill flag on the CSR spill if there's an
additional use of the register after the spill.
This does rely on consistency between the entry block liveins and the
MRI's function live ins, which is not something the verifier checks
now.
When running the tests on PowerPC and x86, the lit test GlobalISel/trunc.ll fails at the memory sanitize step. This seems to be due to wrong invalid logic (which matches even if it shouldn't) and likely missing variable initialisation."
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D95878
When widening, each half of the v2s16 operands needs to be sign extended
for G_ASHR or zero extended for G_LSHR.
Differential Revision: https://reviews.llvm.org/D96048
SALU min/max s32 instructions exist so use them. This means that
regbankselect can handle min/max much like add/sub/mul/shifts.
Differential Revision: https://reviews.llvm.org/D96047
If amdgpu-unsafe-fp-atomics is specified, allow {flat|global}_atomic_add_f32 even if atomic modes don't match.
Differential Revision: https://reviews.llvm.org/D95391
When SGPRs are spilled to VGPRs, they can overwrite any lane. We need
to preserve the value of inactive lanes in function calls, so we save
the register even if it is marked as caller saved.
Also, teach buildPrologSpill to work when no registers are free like in
CodeGen/AMDGPU/pei-scavenge-vgpr-spill.mir and update the comment on
findScratchNonCalleeSaveRegister as it is not used anymore to realign
the stack pointer since D95865.
Differential Revision: https://reviews.llvm.org/D95946
This was only adding undef to the use if the copy itself had a
subregister index. It did not consider the subrange liveness if the
use had a subreg index to begin with.
If we had a pair of copies inside a loop which introduced new liveness
to a subregister which was undef before the loop, we would have a
dummy phi-only segment remaining across the loop body. Later, this
false segment would confuse RenameIndependentSubregs causing it to
introduce IMPLICIT_DEFs with broken value numbering.
It seems always adding the lanes to ShrinkMask is OK, so any
conditions should be purely a compile time filter.
For the fixed ABI, set this in the initial argument constructor,
rather than relying on the allocation logic to set the values. Also
stop passing them for amdgpu_gfx, since the DAG path seems to skip
these. I'm unclear on what amdgpu_gfx's expectations are. This will
allow moving the special input registers out of the normal argument
range.
This reverts commits 62af0305b7cc..677a3529d3e6 from D93708.
They cause failures in the sanitizer builds because of uninitialized
values.
A fix is in D95878, but it might take some time until this is pushed,
so reverting the changes for now.
We don't register i128 as a legal type with addRegisterClass, but it
appears in the list of legal register types. This inconsistency
resulted in the asm constraint lowering trying to use 2 128-bit
registers for these operands. This would leave behind a dead def that
would waste registers.
Regresses GlobalISel tests for i128 load/store, but these aren't very
important right now. Ideally these would not depend on the list of
register types.
This should only consider whether the pressure impact of the bundle at
the given point in the program will decrease the occupancy. High VGPR
pressure was incorrectly blocking the formation of scalar bundles, and
vice versa. This was also blocking bundling from high pressure
situations at other points in the program.
The temporary register is only used to compute the frame pointer.
The frame pointer is overwritten and not used in between, so we
can reuse the frame pointer for the computation, saving one register.
Differential Revision: https://reviews.llvm.org/D95865
Saving callee-save registers happens in whole wave mode. Exec is saved
to a free register, which can be reused to save the frame pointer.
Therefore, saving the fp needs to happen after saving csrs.
Differential Revision: https://reviews.llvm.org/D95861
I guess instructions were marked as frame-setup by accident, they are
restores as part of the epilog.
Differential Revision: https://reviews.llvm.org/D95783
DBG_VALUES placed between memory instructions would change
codegen. Skip over these and re-insert them after the bundle instead
of giving up on bundling.
This would assert with amdgpu-spill-sgpr-to-vgpr disabled when trying to
spill the FP.
Fixes: SWDEV-262704
Reviewed By: RamNalamothu
Differential Revision: https://reviews.llvm.org/D95768
With a context instruction, this would produce a context
error. However, it would continue on and do an out of bounds access of
the empty allocation order array.
SCC was not correctly preserved when entering WWM.
Current lit test was unable to detect this as entry block is
handled differently.
Additionally fix an issue where SCC was unnecessarily preserved
when exiting from WWM to Exact mode.
Reviewed By: foad
Differential Revision: https://reviews.llvm.org/D95500
V_SET_INACTIVE is implemented with S_NOT which clobbers SCC.
Mark sure it is marked appropriately.
Reviewed By: piotr
Differential Revision: https://reviews.llvm.org/D95509
These are widened to a wider UADDE/USUBE, with the overflow value
unused, and with the same synthesis of a new overflow value as for the
O operations.
Reviewed By: paquette
Differential Revision: https://reviews.llvm.org/D95326
Look throught G_PTRTOINT and G_PTR_ADD nodes when looking for constant
offset for buffer stores. This also helps with merging of these instructions
later on.
Differential Revision: https://reviews.llvm.org/D95242
Before the patch it was possible to trigger a constant bus
violation when folding immediates into a shrunk instruction.
The patch adds a check to enforce the legality of the new operand.
Differential Revision: https://reviews.llvm.org/D95527