This reverts commit 254d206ee2a337cb38ba347c896f7c6a14c7f218.
+Added a fix in ExpandDivRem24 to disqualify if DivNumBits exceed 24.
Original commit & msg:
ce6e955ac374f2b86cbbb73b2f32174dffd85f25.
Handle signed and unsigned path differently in getDivNumBits. Using
computeKnownBits, this rejects shrinking unsigned div/rem if operands
exceed signed max since we know NumSignBits will be always 0.
… (SignedMax,UnsignedMax] (#116733)"
This reverts commit 905e831f8c8341e53e7e3adc57fd20b8e08eb999.
Handle signed and unsigned path differently in getDivNumBits. Using
computeKnownBits, this rejects shrinking unsigned div/rem if operands
exceed signed max since we know NumSignBits will be always 0.
Rebased and re-attempt after first one was reverted due to unrelated
failure in LibC (should be fixed by now I'm told).
Do this by using ComputeKnownBits and checking for !isNonNegative and
isUnsigned. This rejects shrinking unsigned div/rem if operands exceed
smax_bitwidth since we know NumSignBits will be always 0.
For targets that support xnack replay feature (gfx8+), the
multi-dword scalar loads shouldn't clobber any register that
holds the src address. The constrained version of the scalar
loads have the early clobber flag attached to the dst operand
to restrict RA from re-allocating any of the src regs for its
dst operand.
This reverts commit adaff46d087799072438dd744b038e6fd50a2d78.
Drop the -O3 checks from default-attributes.hip. I don't know why they
are different on some bots but reverting this is far too disruptive.
Removing it from the codegen pipeline induces a lot of test churn
because llc is no longer optimizing out implicit arguments to kernels.
Mostly mechanical, but there are some creative test updates. I preferred
to take the changes as-is in tests where the ABI isn't relevant. In
cases where it's more relevant, or the optimize out logic was too
ingrained in the test, I pre-run the optimization. Some cases manually
add attributes to disable inputs.
There are many tests that specify a target triple/CPU flags but no
DataLayout which can lead to IR being generated that has unusual
behaviour. This commit attempts to use the default DataLayout based
on the relevant flags if there is no explicit override on the command
line or in the IR file.
One thing that is not currently possible to differentiate from a missing
datalayout `target datalayout = ""` in the IR file since the current
APIs don't allow detecting this case. If it is considered useful to
support this case (instead of passing "-data-layout=" on the command
line), I can change IR parsers to track whether they have seen such a
directive and change the callback type.
Differential Revision: https://reviews.llvm.org/D141060
PR #66334 tried to renumber slot indexes before register allocation, but
the numbering was still affected by list entries for instructions which
had been erased. Fix this to make the register allocator's live range
length heuristics even less dependent on the history of how instructions
have been added to and removed from SlotIndexes's maps.
If a shl node leaves the upper half bits zero / undemanded, then see if we can profitably perform this with a half-width shl and a free trunc/zext.
Followup to D146121
Differential Revision: https://reviews.llvm.org/D155472
RegAllocGreedy uses SlotIndexes::getApproxInstrDistance to approximate
the length of a live range for its heuristics. Renumbering all slot
indexes with the default instruction distance ensures that this estimate
will be as accurate as possible, and will not depend on the history of
how instructions have been added to and removed from SlotIndexes's maps.
This also means that enabling -early-live-intervals, which runs the
SlotIndexes analysis earlier, will not cause large amounts of churn due
to different register allocator decisions.
Try to more aggressively narrow masks of extended values.
This is mainly for cases where the mask is trying to zero out any_extended upper bits, assuming we can zext/trunc the values for free.
This catches a few actual missed folds, as well as helps canonicalize a number of other cases which were being caught in isel etc.
Differential Revision: https://reviews.llvm.org/D145866
This patch contains changes necessary to carry physical condition register (SCC) dependencies through the SDNode scheduler. It adds the edge in the SDNodeScheduler dependency graph instead of inserting the SCC copy between each definition and use. This approach lets the scheduler place instructions in an optimal way placing the copy only when the dependency cannot be resolved.
Reviewed By: rampitec
Differential Revision: https://reviews.llvm.org/D133593
In the 2e29b0138ca243 we introduce a specific solving algorithm
that analyzes the VGPR to SGPR copies use chains and either lowers
the copy to v_readfirstlane_b32 or converts the whole chain to VALU forms.
Same time we still have the code that blindly converts to VALU REG_SEQUENCE and PHIs
in case they produce SGPR but have VGPRs input operands. In case the REG_SEQUENCE and PHIs
are in the VGPR to SGPR copy use chain, and this chain was considered long enough to convert
copy to v_readfistlane_b32, further lowering them to VALU leads to several kinds of issues.
At first, we have v_readfistlane_b32 which is completely useless because most parts of its use chain
were moved to VALU forms. Second, we may encounter subtle bugs related to the EXEC-dependent CF
because of the weird mixing of SALU and VALU instructions.
This change removes the code that moves REG_SEQUENCE and PHIs to VALU. Instead, we use the fact
that both REG_SEQUENCE and PHIs have copy semantics. That is, if they define SGPR but have VGPR inputs,
we insert VGPR to SGPR copies to make them pure SGPR. Then, the new copies are processed by the common
VGPR to SGPR lowering algorithm.
This is Part 2 in the series of commits aiming at the massive refactoring of the SIFixSGPRCopies pass.
Reviewed By: rampitec
Differential Revision: https://reviews.llvm.org/D130367
In the 2e29b0138ca243 we introduce a specific solving algorithm
that analyzes the VGPR to SGPR copies use chains and either lowers
the copy to v_readfirstlane_b32 or converts the whole chain to VALU forms.
Same time we still have the code that blindly converts to VALU REG_SEQUENCE and PHIs
in case they produce SGPR but have VGPRs input operands. In case the REG_SEQUENCE and PHIs
are in the VGPR to SGPR copy use chain, and this chain was considered long enough to convert
copy to v_readfistlane_b32, further lowering them to VALU leads to several kinds of issues.
At first, we have v_readfistlane_b32 which is completely useless because most parts of its use chain
were moved to VALU forms. Second, we may encounter subtle bugs related to the EXEC-dependent CF
because of the weird mixing of SALU and VALU instructions.
This change removes the code that moves REG_SEQUENCE and PHIs to VALU. Instead, we use the fact
that both REG_SEQUENCE and PHIs have copy semantics. That is, if they define SGPR but have VGPR inputs,
we insert VGPR to SGPR copies to make them pure SGPR. Then, the new copies are processed by the common
VGPR to SGPR lowering algorithm.
This is Part 2 in the series of commits aiming at the massive refactoring of the SIFixSGPRCopies pass.
Reviewed By: rampitec
Differential Revision: https://reviews.llvm.org/D130367
SimplifyDemandedBits currently early-outs for multi-use values beyond the root node (just returning the knownbits), which is missing a number of optimizations as there are plenty of cases where we can still simplify when initially demanding all elements/bits.
@lenary has confirmed that the test cases in aea-erratum-fix.ll need refactoring and the current increase codegen is not a major concern.
Differential Revision: https://reviews.llvm.org/D129765
Since the divergence-driven instruction selection has been enabled for AMDGPU,
all the uniform instructions are expected to be selected to SALU form, except those not having one.
VGPR to SGPR copies appear in MIR to connect values producers and consumers. This change implements an algorithm
that evolves a reasonable tradeoff between the profit achieved from keeping the uniform instructions in SALU form
and overhead introduced by the data transfer between the VGPRs and SGPRs.
Reviewed By: rampitec
Differential Revision: https://reviews.llvm.org/D128252
Fold immediates regardless of how many uses they have. This is expected
to increase overall code size, but decrease register usage.
Differential Revision: https://reviews.llvm.org/D114644
Previously SIFoldOperands::foldInstOperand would only fold a
non-inlinable immediate into a single user, so as not to increase code
size by adding the same 32-bit literal operand to many instructions.
This patch removes that restriction, so that a non-inlinable immediate
will be folded into any number of users. The rationale is:
- It reduces the number of registers used for holding constant values,
which might increase occupancy. (On the other hand, many of these
registers are SGPRs which no longer affect occupancy on GFX10+.)
- It reduces ALU stalls between the instruction that loads a constant
into a register, and the instruction that uses it.
- The above benefits are expected to outweigh any increase in code size.
Differential Revision: https://reviews.llvm.org/D114643
Pulled out of D77804 as its going to be easier to address the regressions individually.
This patch allows SimplifyDemandedBits to call SimplifyMultipleUseDemandedBits in cases where the source operand has other uses, enabling us to peek through the shifted value if we don't demand all the bits/elts.
The lost RISCV gorc2 fold shouldn't be a problem - instcombine would have already destroyed that pattern - see https://github.com/llvm/llvm-project/issues/50553
Differential Revision: https://reviews.llvm.org/D124839
Use shufflevector to do the subvector extracts. This allows a lot more
load merging on AMDGPU and also on NVPTX when <2 x half> is involved.
Differential Revision: https://reviews.llvm.org/D117219
This reverts commit 640beb38e7710b939b3cfb3f4c54accc694b1d30.
That commit caused performance degradtion in Quicksilver test QS:sGPU and a functional test failure in (rocPRIM rocprim.device_segmented_radix_sort).
Reverting until we have a better solution to s_cselect_b64 codegen cleanup
Change-Id: Ifc167b3c2dae7a65920676f22a97ba76485f3456
Reviewed By: kzhuravl
Differential Revision: https://reviews.llvm.org/D116686
Change-Id: I1abf49b74a7e2ba0e0205f747a4154a468b9d7f2
This reverts commit 859ebca744e634dcc89a2294ffa41574f947bd62.
The change contained many unrelated changes and e.g. restored
unit test failes for the old lld port.
This reverts commit 640beb38e7710b939b3cfb3f4c54accc694b1d30.
That commit caused performance degradtion in Quicksilver test QS:sGPU and a functional test failure in (rocPRIM rocprim.device_segmented_radix_sort).
Reverting until we have a better solution to s_cselect_b64 codegen cleanup
Change-Id: Ibf8e397df94001f248fba609f072088a46abae08
Reviewed By: kzhuravl
Differential Revision: https://reviews.llvm.org/D115960
Change-Id: Id169459ce4dfffa857d5645a0af50b0063ce1105
Using a BufferSize of one for memory ProcResources will result in better
ILP since it more accurately models the dependencies between memory ops
and their consumers on an in-order processor. After this change, the
scheduler will treat the data edges from loads as blocking so that
stalls are guaranteed when waiting for data to be retreaved from memory.
Since we don't actually track waitcnt here, this should do a better job
at modeling their behavior.
Practically, this means that the scheduler will trigger the 'STALL'
heuristic more often.
This type of change needs to be evaluated experimentally. Preliminary
results are positive.
Fixes: SWDEV-282962
Reviewed By: rampitec
Differential Revision: https://reviews.llvm.org/D114777
Introduce V_MOV_B32_indirect_read for indexed vgpr reads
(and rename the old V_MOV_B32_indirect to
V_MOV_B32_indirect_write) so they can be unambiguously
distinguished from regular V_MOV_B32_e32. Previously they
were distinguished by looking for extra implicit operands
but this is fragile because regular moves sometimes have
extra implicit operands too:
- either by accident, when instructions end up with
duplicate implicit operands (see e.g. D100939)
- or by design, when SIInstrInfo::copyPhysReg breaks a
multi-dword copy into individual subreg mov instructions
and adds implicit operands for the super-register.
The effect of this is that SIInstrInfo::isFoldableCopy can
be simplified and identifies more foldable copies. The test
diffs show that more immediate 0 values have been folded as
inline operands.
SIInstrInfo::isReallyTriviallyReMaterializable could
probably be simplified too but that is not part of this
patch.
Differential Revision: https://reviews.llvm.org/D114230
The old expansion open-coded a 64-bit addition in a strange way, by
adding the high parts *without* carry-in from the low part, and then
adding the carry back in later on. Fixing this saves a couple of
instructions and makes the code much easier to understand.
Differential Revision: https://reviews.llvm.org/D113679
