Tries to make the different scheduling stages a bit more self contained and
modifiable. Intended to be NFC. Preface to other changes.
Reviewed By: rampitec
Differential Revision: https://reviews.llvm.org/D130147
Set the priorities consistently to number of registers in the tuple -
1. Previously we started at 1, and also tried to give SGPR higher
values than VGPRs. There's no point in assigning SGPRs higher values
now that those are allocated in a separate regalloc run.
This avoids overflowing the 5 bits used for the class priority in the
allocation heuristic for 32 element tuples. This avoids some cases
where smaller registers unexpectedly get prioritized over larger.
This patch merges a consecutive sequence of
s_or_saveexec s_o, s_i
s_xor exec, exec, s_o
into a single
s_andn2_saveexec s_o, s_i instruction.
This patch also cleans up the SIOptimizeExecMasking pass a bit.
Reviewed By: nhaehnle
Differential Revision: https://reviews.llvm.org/D129073
VOPC DPP should not be formed when the row_mask and bank_mask are not
0xf (full) because the resulting VOP DPP would have different semantics
than the MOV DPP followed by VOP. Existing checks in GCNDPPCombine cover
this case but for different reasons, so assert the property for
future-proofing.
Reviewed By: nhaehnle
Differential Revision: https://reviews.llvm.org/D130101
For the longest time we used `AAValueSimplify` and
`genericValueTraversal` to determine "potential values". This was
problematic for many reasons:
- We recomputed the result a lot as there was no caching for the 9
locations calling `genericValueTraversal`.
- We added the idea of "intra" vs. "inter" procedural simplification
only as an afterthought. `genericValueTraversal` did offer an option
but `AAValueSimplify` did not. Thus, we might end up with "too much"
simplification in certain situations and then gave up on it.
- Because `genericValueTraversal` was not a real `AA` we ended up with
problems like the infinite recursion bug (#54981) as well as code
duplication.
This patch introduces `AAPotentialValues` and replaces the
`AAValueSimplify` uses with it. `genericValueTraversal` is folded into
`AAPotentialValues` as are the instruction simplifications performed in
`AAValueSimplify` before. We further distinguish "intra" and "inter"
procedural simplification now.
`AAValueSimplify` was not deleted as we haven't ported the
re-materialization of instructions yet. There are other differences over
the former handling, e.g., we may not fold trivially foldable
instructions right now, e.g., `add i32 1, 1` is not folded to `i32 2`
but if an operand would be simplified to `i32 1` we would fold it still.
We are also even more aware of function/SCC boundaries in CGSCC passes,
which is good even if some tests look like they regress.
Fixes: https://github.com/llvm/llvm-project/issues/54981
Note: A previous version was flawed and consequently reverted in
6555558a80.
Implement an intrinsic for use lowering LDS variables to different
addresses from different kernels. This will allow kernels that cannot
reach an LDS variable to avoid wasting space for it.
There are a number of implicit arguments accessed by intrinsic already
so this implementation closely follows the existing handling. It is slightly
novel in that this SGPR is written by the kernel prologue.
It is necessary in the general case to put variables at different addresses
such that they can be compactly allocated and thus necessary for an
indirect function call to have some means of determining where a
given variable was allocated. Claiming an arbitrary SGPR into which
an integer can be written by the kernel, in this implementation based
on metadata associated with that kernel, which is then passed on to
indirect call sites is sufficient to determine the variable address.
The intent is to emit a __const array of LDS addresses and index into it.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D125060
For most DPP instructions, the old operand stores the value that was in
the current lane before the DPP operation, and is tied to the
destination. For VOPC DPP, this is unnecessary and incorrect.
There appears to have been a latent bug related to D122737 with
SIInstrInfo::isOperandLegal. If you checked if a register operand was legal
when the InstructionDesc expected an immediate, it reported that is valid.
Its fix is necessary for and tested in this patch.
Reviewed By: foad, rampitec
Differential Revision: https://reviews.llvm.org/D130040
AMDGPUPerfHintAnalysis doesn't set the memory bound attribute if
FuncInfo::InstCost outweighs MemInstCost even if we have a basic block
with relatively high global memory access. GCNSchedStrategy could revert
optimal scheduling in favour of occupancy which seems to degrade
performance for some kernels. This change introduces the
HasDenseGlobalMemAcc metric in the heuristic that makes the analysis
more conservative in these cases.
This fixes SWDEV-334259/SWDEV-343932
Differential Revision: https://reviews.llvm.org/D129759
This was stored in LiveIntervals, but not actually used for anything
related to LiveIntervals. It was only used in one check for if a load
instruction is rematerializable. I also don't think this was entirely
correct, since it was implicitly assuming constant loads are also
dereferenceable.
Remove this and rely only on the invariant+dereferenceable flags in
the memory operand. Set the flag based on the AA query upfront. This
should have the same net benefit, but has the possible disadvantage of
making this AA query nonlazy.
Preserve the behavior of assuming pointsToConstantMemory implying
dereferenceable for now, but maybe this should be changed.
Parse op_sel for *_e64_dpp VOP3 opcodes.
Depends on D129637 and setting of VOP3_OPSEL in dpp pseudos.
Differential Revision: https://reviews.llvm.org/D129767
Saves some add instructions on a couple Rage 2 shaders and is also a
prerequisite for a coming-soon change matching (register + immediate)
offsets.
Reviewed By: foad, arsenm
Differential Revision: https://reviews.llvm.org/D129095
This change introduces the dynamic stack boolean field to code-object-v3
and above under the code properties of the kernel descriptor and under
the kernel metadata map of NT_AMDGPU_METADATA. This field corresponds to
the is_dynamic_callstack field of amd_kernel_code_t.
Differential Revision: https://reviews.llvm.org/D128344
Further improve liveness copying for CC register post optimization
by mirroring live internal splits.
The fixes a bug in register allocation when CC register liveness
is extended across a branches instead of split.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D129557
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
D114999 added code to kill an immediate def if it was folded into its
only use by convertToThreeAddress. This patch updates LiveVariables when
that happens in order to fix verification failures exposed by D129213.
Differential Revision: https://reviews.llvm.org/D129661
D25618 added a method to verify the instruction predicates for an
emitted instruction, through verifyInstructionPredicates added into
<Target>MCCodeEmitter::encodeInstruction. This is a very useful idea,
but the implementation inside MCCodeEmitter made it only fire for object
files, not assembly which most of the llvm test suite uses.
This patch moves the code into the <Target>_MC::verifyInstructionPredicates
method, inside the InstrInfo. The allows it to be called from other
places, such as in this patch where it is called from the
<Target>AsmPrinter::emitInstruction methods which should trigger for
both assembly and object files. It can also be called from other places
such as verifyInstruction, but that is not done here (it tends to catch
errors earlier, but in reality just shows all the mir tests that have
incorrect feature predicates). The interface was also simplified
slightly, moving computeAvailableFeatures into the function so that it
does not need to be called externally.
The ARM, AMDGPU (but not R600), AVR, Mips and X86 backends all currently
show errors in the test-suite, so have been disabled with FIXME
comments.
Recommitted with some fixes for the leftover MCII variables in release
builds.
Differential Revision: https://reviews.llvm.org/D129506
The SI machine scheduler inherits from ScheduleDAGMI.
This patch adds support for a few features that are implemented
in ScheduleDAGMI (or its base classes) that were missing so far
because their support is implemented in overridden functions.
* Support cl::opt -view-misched-dags
This option allows to open a graphical window of the scheduling DAG.
* Support cl::opt -misched-print-dags
This option allows to print the scheduling DAG in text form.
* After constructing the scheduling DAG, call postprocessDAG()
to apply any registered DAG mutations.
Note that currently there are no mutations defined in AMDGPUTargetMachine.cpp
in case SIScheduler is used.
Still add this to avoid surprises in the future in case mutations are added.
Differential Revision: https://reviews.llvm.org/D128808
This reverts commit e2fb8c0f4b as it does
not build for Release builds, and some buildbots are giving more warning
than I saw locally. Reverting to fix those issues.
D25618 added a method to verify the instruction predicates for an
emitted instruction, through verifyInstructionPredicates added into
<Target>MCCodeEmitter::encodeInstruction. This is a very useful idea,
but the implementation inside MCCodeEmitter made it only fire for object
files, not assembly which most of the llvm test suite uses.
This patch moves the code into the <Target>_MC::verifyInstructionPredicates
method, inside the InstrInfo. The allows it to be called from other
places, such as in this patch where it is called from the
<Target>AsmPrinter::emitInstruction methods which should trigger for
both assembly and object files. It can also be called from other places
such as verifyInstruction, but that is not done here (it tends to catch
errors earlier, but in reality just shows all the mir tests that have
incorrect feature predicates). The interface was also simplified
slightly, moving computeAvailableFeatures into the function so that it
does not need to be called externally.
The ARM, AMDGPU (but not R600), AVR, Mips and X86 backends all currently
show errors in the test-suite, so have been disabled with FIXME
comments.
Differential Revision: https://reviews.llvm.org/D129506
The availability of LiveIntervals affects kill flags in the output, so
declare the use to avoid strange effects where the output of this pass
is different depending on what other passes are scheduled after it.
Differential Revision: https://reviews.llvm.org/D129555
Remove the bound in the definition, since it's not guaranteed/could
provide a false sense of security (I'd be inclined to go further and
change this to a pointer parameter, since that's what it really is - but
figured I'd preserve some of the author's intent here)
This change replaces the C++ predicates with the HasNoUse builtin
predicate that would enable the no-ret atomic op selection in
GlobalISel.
Differential Revision: https://reviews.llvm.org/D125213
This patch removes the predicate for return atomic ops and uses
AddedComplexity to distinguish its selection from its no return variant.
This will produce better matchers that doesn't unnecessarily check for
the negated predicate if the initial predicate failed. Also, it
simplifies the enabling of no return atomic ops selection in GlobalISel.
Differential Revision: https://reviews.llvm.org/D128241
This patch adds the support for `fmax` and `fmin` operations in `atomicrmw`
instruction. For now (at least in this patch), the instruction will be expanded
to CAS loop. There are already a couple of targets supporting the feature. I'll
create another patch(es) to enable them accordingly.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D127041
This patch removes a bit of code duplication and
moves the v_cmpx optimization out of the
runOnMachineFunction pass.
Reviewed By: foad
Differential Revision: https://reviews.llvm.org/D129086
Merge tests and fixes from D128110 and D128315 on top of already
committed D128800.
Original author: arsenm
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D128882
Modifies the GCNDPPCombine pass to enable DPP formation for the new DPP
instruction in gfx11, namely VOP3 encoded instructions with DPP and VOPC
with DPP.
Depends on D128656
Reviewed By: #amdgpu, rampitec
Differential Revision: https://reviews.llvm.org/D128682
We form VOPD instructions in the GCNCreateVOPD pass by combining
back-to-back component instructions. There are strict register
constraints for creating a legal VOPD, namely that the matching operands
(e.g. src0x and src0y, src1x and src1y) must be in different register
banks. We add a PostRA scheduler
mutation to put possible VOPD components back-to-back.
Depends on D128442, D128270
Reviewed By: #amdgpu, rampitec
Differential Revision: https://reviews.llvm.org/D128656
Tell the matcher what we are looking for instead of matching everything
and then discarding the result if doesn't fit.
Reviewed By: foad
Differential Revision: https://reviews.llvm.org/D128171
Update intrinsics to use n x f16 and n x i16 instead
of 32-bit types. This may avoid the need for a bitcast
and is probably less confusing.
Depends on making v16f16 and v16i16 types legal.
Reviewed By: rampitec
Differential Revision: https://reviews.llvm.org/D128951
GFX11 has a new message type MSG_DEALLOC_VGPRS which can be used to
release a shader's VGPRs. Sending this at the end of a shader (just
before the s_endpgm) can help overall system performance in cases where
the s_endpgm would have to wait for outstanding VMEM stores to complete
before releasing the VGPRs.
Differential Revision: https://reviews.llvm.org/D128442
Follow up to D127894, new liveness update code needs to handle
the case where S_ANDN2 input must be extended through loops when
V_CNDMASK_B32 has been hoisted.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D128800
D106023 excluded 16-bit instructions from rematerialization, with the
justification that we can't rematerialize instructions that preserve
the high bits (plus the instructions which do are a confusing mess
between different subtargets). This doesn't make sense to me as a
problem since cases where we would rely on the high bit behavior would
still need to be represented as a register value constraint with a
tied operand. It's not a hidden side effect and should still be
rematerializable.
Without this, the new test case would fail with:
AMDGPUInstPrinter.cpp:545: void llvm::AMDGPUInstPrinter::printImmediate64(uint64_t, const llvm::MCSubtargetInfo &, llvm::raw_ostream &): Assertion `isUInt<32>(Imm) || Imm == 0x3fc45f306dc9c882' failed.
Differential Revision: https://reviews.llvm.org/D128435
The new resumable mca::Pipeline capability introduced in this patch
allows users to save the current state of pipeline and resume from the
very checkpoint.
It is better (but not require) to use with the new IncrementalSourceMgr,
where users can add mca::Instruction incrementally rather than having a
fixed number of instructions ahead-of-time.
Note that we're using unit tests to test these new features. Because
integrating them into the `llvm-mca` tool will make too many churns.
Differential Revision: https://reviews.llvm.org/D127083
VOPD is a new encoding for dual-issue instructions for use in wave32.
This patch includes MC layer support only.
A VOPD instruction is constituted of an X component (for which there are
13 possible opcodes) and a Y component (for which there are the 13 X
opcodes plus 3 more). Most of the complexity in defining and parsing
a VOPD operation arises from the possible different total numbers of
operands and deferred parsing of certain operands depending on the
constituent X and Y opcodes.
Reviewed By: dp
Differential Revision: https://reviews.llvm.org/D128218
waitcnt vmcnt instructions are currently generated in loop bodies before using
values loaded outside of the loop. In some cases, it is better to flush the
vmcnt counter in a loop preheader before entering the loop body. This patch
detects these cases and generates waitcnt instructions to flush the counter.
Reviewed By: foad
Differential Revision: https://reviews.llvm.org/D115747
In GFX11 ShaderType is determined by the hardware and should no longer
be written into bits[3:2] of the ds_ordered_count offset field.
Differential Revision: https://reviews.llvm.org/D128196
Running iwyu-diff on LLVM codebase since fb67d683db detected a few
regressions, fixing them.
The impact on preprocessed output is negligible: -4k lines.
Jon Chesterfield