It is possible for copies or spills to be inserted in the middle of indirect
addressing sequences which use VGPR indexing. Spills to accvgprs could be
effected by the indexing mode.
Add new pseudo instructions that are expanded after register allocation to avoid
the problematic spill or copy placement.
Differential Revision: https://reviews.llvm.org/D91048
Add a calling convention called amdgpu_gfx for real function calls
within graphics shaders. For the moment, this uses the same calling
convention as other calls in amdgpu, with registers excluded for return
address, stack pointer and stack buffer descriptor.
Differential Revision: https://reviews.llvm.org/D88540
The insertion of waterfall loops splits the current basic block into
three blocks. So the basic block that we iterate over must be updated.
This failed assert(!NodePtr->isKnownSentinel()) in ilist_iterator for
divergent calls in branches before.
Differential Revision: https://reviews.llvm.org/D90596
This reverts r227987 "R600/SI: Determine target-specific encoding of READLANE and WRITELANE early v2".
All the codegen changes are caused by the post-RA scheduler no longer
treating readlane/writelane as scheduling barriers due to having
unmodelled side effects. (The pseudos are hasSideEffects = 0, but the
real instructions are hasSideEffects = ? which TableGen conservatively
treats as 1.)
Differential Revision: https://reviews.llvm.org/D90401
V_DIV_SCALE_F32/F64 are VOP3B encoded so they can't use the ABS src
modifier, but they can still use NEG and the usual output modifiers.
This partially reverts 3b99f12a4e "AMDGPU: Remove modifiers from v_div_scale_*".
Differential Revision: https://reviews.llvm.org/D90296
This does not change anything at the moment, but needed for
D89170. In that change I am probing a physical SGPR to see if
it is legal. RC is SReg_32, but DRC for scratch instructions
is SReg_32_XEXEC_HI and test fails.
That is sufficient just to check if DRC contains a register
here in case of physreg. Physregs also do not use subregs
so the subreg handling below is irrelevant for these.
Differential Revision: https://reviews.llvm.org/D90064
I was wrong in thinking that MRI.use_instructions return unique instructions and mislead Jay in his previous patch D64393.
First loop counted more instructions than it was in reality and the second loop went beyond the basic block with that counter.
I used Jay's previous code that relied on MRI.use_operands to constrain the number of instructions to check among.
modifiesRegister is inlined to reduce the number of passes over instruction operands and added assert on BB end boundary.
Differential Revision: https://reviews.llvm.org/D89386
If a target can encode multiple wait-states into a noop allow emitting such
instructions directly.
Reviewed By: rampitec, dmgreen
Differential Revision: https://reviews.llvm.org/D89753
This would end up killing part of the result super-register, resulting
in a verifier error on a later use of the overlapping registers. We
could add kills of any non-aliasing registers, but we should be moving
away from relying on kill flags.
Generate the minimal set of s_mov instructions required when
expanding a SGPR copy operation in copyPhysReg.
Reviewed By: foad
Differential Revision: https://reviews.llvm.org/D89187
This can fix an asan failure like below.
==15856==ERROR: AddressSanitizer: use-after-poison on address ...
READ of size 8 at 0x6210001a3cb0 thread T0
#0 llvm::MachineInstr::getParent()
#1 llvm::LiveVariables::VarInfo::findKill()
#2 TwoAddressInstructionPass::rescheduleMIBelowKill()
#3 TwoAddressInstructionPass::tryInstructionTransform()
#4 TwoAddressInstructionPass::runOnMachineFunction()
We need to update the Kills if we replace instructions. The Kills
may be later accessed within TwoAddressInstruction pass.
Differential Revision: https://reviews.llvm.org/D89092
Extend loadSRsrcFromVGPR to allow moving a range of instructions into
the loop. The call instruction is surrounded by copies into physical
registers which should be part of the waterfall loop.
Differential Revision: https://reviews.llvm.org/D88291
Fix the verifier so that overlapping SGPR operands are counted
independently. We cannot assume that overlapping SGPR accesses
only count as a single constant bus use.
The exception is implicit uses which do not add to constant bus
usage (only) when overlapping.
Reviewed By: rampitec
Differential Revision: https://reviews.llvm.org/D87748
Since 6524a7a2b9, this would sometimes
not emit the or to exec at the beginning of the block, where it really
has to be. If there is an instruction that defines one of the source
operands, split the block and turn the si_end_cf into a terminator.
This avoids regressions when regalloc fast is switched to inserting
reloads at the beginning of the block, instead of spills at the end of
the block.
In a future change, this should always split the block.
Pre-gfx10 all MODE-setting instructions were S_SETREG_B32 which is
marked as having unmodeled side effects, which makes the machine
scheduler treat it as a barrier. Now that we have proper implicit $mode
operands we can use a no-side-effects S_SETREG_B32_mode pseudo instead
for setregs that only touch the FP MODE bits, to give the scheduler more
freedom.
Differential Revision: https://reviews.llvm.org/D87446
- When an operand is changed into an immediate value or like, ensure their
target flags being cleared or set properly.
Differential Revision: https://reviews.llvm.org/D87109
There is no justification for changing vcc_lo to vcc
when shrinking V_CNDMASK, and such a change could
later confuse live variable analysis.
Make sure the original register is preserved.
Differential Revision: https://reviews.llvm.org/D86541
Summary:
When the resource descriptor is of vgpr, we need a waterfall loop
to read into a sgpr. In this patchm we generalized the implementation
to work for any regster class sizes, and extend the work to MIMG
instructions.
Fixes: SWDEV-223405
Reviewers:
arsenm, nhaehnle
Differential Revision:
https://reviews.llvm.org/D82603
The previous implementation was incorrect, and based off incorrect
instruction definitions. Unfortunately we can't match natural
addressing in a lot of cases due to the shift/scale applied in
getelementptrs. This relies on reducing the 64-bit shift to 32-bits.
Fix 64-bit copy to SCC by restricting the pattern resulting
in such a copy to subtargets supporting 64-bit scalar compare,
and mapping the copy to S_CMP_LG_U64.
Before introducing the S_CSELECT pattern with explicit SCC
(0045786f14), there was no need
for handling 64-bit copy to SCC ($scc = COPY sreg_64).
The proposed handling to read only the low bits was however
based on a false premise that it is only one bit that matters,
while in fact the copy source might be a vector of booleans and
all bits need to be considered.
The practical problem of mapping the 64-bit copy to SCC is that
the natural instruction to use (S_CMP_LG_U64) is not available
on old hardware. Fix it by restricting the problematic pattern
to subtargets supporting the instruction (hasScalarCompareEq64).
Differential Revision: https://reviews.llvm.org/D85207
Avoid recursively calling copyPhysReg for AGPR handling. This was
dropping the necessary super register implicit defs to avoid liveness
verifier errors.
Get rid of all fixmes and base heuristic on `num-clustered-dwords`. The main intuition behind this is as
follows. The existing heuristic roughly summarizes as below:
* Assume, all the mem ops instructions participating in the clustering process, loads/stores same num bytes
* If num bytes loaded by each mem op is 4 bytes, then cluster at max 5 mem ops, that is at max 20 bytes
* If num bytes loaded by each mem op is 8 bytes, then cluster at max 3 mem ops, that is at max 24 bytes
* If num bytes loaded by each mem op is 16 bytes, then cluster at max 2 mem ops, that is at max 32 bytes
So, we need to make sure that the new heuristic do not completey deviate away from the above one, and it
properly handles both the sub-word loads and the wide loads.
Reviewed By: arsenm, rampitec
Differential Revision: https://reviews.llvm.org/D84354
Currently GlobalISel doesn't force all VGPR phi operands to VGPRs, so
this hit a case where it was queried with a VGPR and SGPR. This could
arguably be a verifier error, but it's currently not.
This is in preparation for fixing multiple problems with the way AGPR
copies are handled, but this change is NFC itself. First, it's relying
on recursively calling copyPhysReg, which is losing information
necessary to get correct super register handling.
Second, it's constructing a new RegScavenger and doing a O(N^2) walk
on every single sub-spill for every AGPR tuple copy. Third, it's using
the forward form of the scavenger, and not using the preferred
backwards scan.
The hardware has created a real mess in the naming for add/sub, which
have been renamed basically every generation. Switch the carry out
pseudos to have the gfx9/gfx10 names. We were using the original SI/CI
v_add_i32/v_sub_i32 names. Later targets reintroduced these names as
carryless instructions with a saturating clamp bit, which we do not
define. Do this rename so we can unambiguously add these missing
instructions.
The carry-in versions should also be renamed, but at least those had a
consistent _u32 name to begin with. The 16-bit instructions were also
renamed, but aren't ambiguous.
This does regress assembler error message quality in some cases. In
mismatched wave32/wave64 situations, this will switch from
"unsupported instruction" to "invalid operand", with the error
pointing at the wrong position. I couldn't quite follow how the
assembler selects these, but the previous behavior seemed accidental
to me. It looked like there was a partial attempt to handle this which
was never completed (i.e. there is an AMDGPUOperand::isBoolReg but it
isn't used for anything).
If the original register operand had a subregister, it wasn't getting
cleared. This resulted in reinterpreted the subreg index as
unrecognized target flags, which produced unparseable MIR.
Before this instruction supported output values, it fit fairly
naturally as a terminator. However, being a terminator while also
supporting outputs causes some trouble, as the physreg->vreg COPY
operations cannot be in the same block.
Modeling it as a non-terminator allows it to be handled the same way
as invoke is handled already.
Most of the changes here were created by auditing all the existing
users of MachineBasicBlock::isEHPad() and
MachineBasicBlock::hasEHPadSuccessor(), and adding calls to
isInlineAsmBrIndirectTarget or mayHaveInlineAsmBr, as appropriate.
Reviewed By: nickdesaulniers, void
Differential Revision: https://reviews.llvm.org/D79794
Condition `LiteralCount` is checked both in an outer and in an inner
`if` statement in `SIInstrInfo::verifyInstruction()`. This patch removes
the redundant inner check.
The issue was found using `clang-tidy` check under review
`misc-redundant-condition`. See https://reviews.llvm.org/D81272.
Differential Revision: https://reviews.llvm.org/D82555
Summary:
Add patterns to select s_cselect in the isel.
Handle more cases of implicit SCC accesses in si-fix-sgpr-copies
to allow new patterns to work.
Subscribers: arsenm, kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, asbirlea, kerbowa, llvm-commits
Tags: #llvm
Re-commit D81925 with a bugfix D82370.
Differential Revision: https://reviews.llvm.org/D81925
Differential Revision: https://reviews.llvm.org/D82370
Summary:
Without fixImplicitOperands we may end up creating default implicit operands
that are the wrong wave size
Includes simple test that provokes insertBranch in the correct way to expose the
issue being fixed.
Change-Id: I92bdcdee9fcb7b4d91529b84e76a48ac8218483e
Subscribers: arsenm, kzhuravl, jvesely, wdng, nhaehnle, yaxunl, tpr, t-tye, hiraditya, kerbowa, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D82459
Summary:
Make use of both the - (1) clustered bytes and (2) cluster length, to decide on
the max number of mem ops that can be clustered. On an average, when loads
are dword or smaller, consider `5` as max threshold, otherwise `4`. This
heuristic is purely based on different experimentation conducted, and there is
no analytical logic here.
Reviewers: foad, rampitec, arsenm, vpykhtin
Reviewed By: rampitec
Subscribers: llvm-commits, kerbowa, hiraditya, t-tye, Anastasia, tpr, dstuttard, yaxunl, nhaehnle, wdng, jvesely, kzhuravl, thakis
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D82393
Always prefer to clobber input SGPRs and restore them after the
spill. This applies to both spills to VGPRs and scratch.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D81914
Summary:
Add patterns to select s_cselect in the isel.
Handle more cases of implicit SCC accesses in si-fix-sgpr-copies
to allow new patterns to work.
Subscribers: arsenm, kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, asbirlea, kerbowa, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D81925
It seems to be a hardware defect that the half inline constants do not
work as expected for the 16-bit integer operations (the inverse does
work correctly). Experimentation seems to show these are really
reading the 32-bit inline constants, which can be observed by writing
inline asm using op_sel to see what's in the high half of the
constant. Theoretically we could fold the high halves of the 32-bit
constants using op_sel.
The *_asm_all.s MC tests are broken, and I don't know where the script
to autogenerate these are. I started manually fixing it, but there's
just too many cases to fix. This also does break the
assembler/disassembler support for these values, and I'm not sure what
to do about it. These are still valid encodings, so it seems like you
should be able to use them in some way. If you wrote assembly using
them, you could have really meant it (perhaps to read the high bits
with op_sel?). The disassembler will print the invalid literal
constant which will fail to re-assemble. The behavior is also
different depending on the use context. Consider this example, which
was previously accepted and encoded using the inline constant:
v_mad_i16 v5, v1, -4.0, v3
; encoding: [0x05,0x00,0xec,0xd1,0x01,0xef,0x0d,0x04]
In contexts where an inline immediate is required (such as on gfx8/9),
this will now be rejected. For gfx10, this will produce the literal
encoding and change the printed format:
v_mad_i16 v5, v1, 0xc400, v3
; encoding: [0x05,0x00,0x5e,0xd7,0x01,0xff,0x0d,0x04,0x00,0xc4,0x00,0x00]
This is just another variation of the issue that we don't perfectly
handle round trip assembly/disassembly due to not tracking how
immediates were encoded. This doesn't matter much in practice, since
compilers don't emit the suboptimal encoding. I doubt any users are
relying on this behavior (although I did make use of the old behavior
to figure out what was wrong).
Fixes bug 46302.
Summary:
Make use of both the - (1) clustered bytes and (2) cluster length, to decide on
the max number of mem ops that can be clustered. On an average, when loads
are dword or smaller, consider `5` as max threshold, otherwise `4`. This heuristic
is purely based on different experimentation conducted, and there is no analytical
logic here.
Reviewers: foad, rampitec, arsenm, vpykhtin
Reviewed By: foad, rampitec
Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, Anastasia, t-tye, hiraditya, kerbowa, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D81085
These are scalar instructions that change vector instructions, so they
should not be executed without any active lanes.
The implementation of -amdgpu-skip-threshold also seem to be backwards
from expected, since decreasing it prevents removal.
Summary:
While clustering mem ops, AMDGPU target needs to consider number of clustered bytes
to decide on max number of mem ops that can be clustered. This patch adds support to pass
number of clustered bytes to target mem ops clustering logic.
Reviewers: foad, rampitec, arsenm, vpykhtin, javedabsar
Reviewed By: foad
Subscribers: MatzeB, kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, javed.absar, kerbowa, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D80545
This will enable selecting non-entry block allocas. Skip the SP write
check in the base isSchedulingBoundary implementation to preserve the
previous scheduling behavior and avoid test churn. It's apparently for
compile time reasons, but if we were to use this more work would be
needed since in some of the failing tests, we seem to incorrectly get
hazard nops inserted.
All 3 passes that change instruction encodings were dropping MI
flags. This avoids scheduling regressions caused by setting
mayRaiseFPExceptions on FP instructions for non-strictfp functions.
The vector equivalent has backwards operands, but the scalar version
does not. The passes that use these hooks aren't enabled by default,
so this doesn't really change anything.
This a hack to fix illegal 32 to 16 bit copies.
The problem is when we make 16 bit subregs legal it creates
a huge amount of failures which can only be resolved at once
without a temporary hack like this.
The next step is to change operands, instruction definitions
and patterns until this hack is not needed.
Differential Revision: https://reviews.llvm.org/D79119
Summary: This change enables all kind of carry out ISD opcodes to be selected according to the node divergence.
Reviewers: rampitec, arsenm, vpykhtin
Reviewed By: rampitec
Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, kerbowa, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D78091
It allows it not to crash and analyze 16 bit subregs if those
appear in the instructions. At the same time it does not attempt
to reassign these. It still can correctly identify register
banks to let larger registers to be reassigned.
More work will be needed here when real instructions will use
these registers and more tests as well.
Differential Revision: https://reviews.llvm.org/D78772
These are used in SReg_32 and when we start to use SGPR_LO16
there will be compaints that not all registers in RC support
all subreg indexes. For now it is NFC.
Unused regunits are reserved so that verifier does not complain
about missing phys reg live-ins.
Differential Revision: https://reviews.llvm.org/D78591
These are used in SReg_32 and when we start to use SGPR_LO16
there will be compaints that not all registers in RC support
all subreg indexes. For now it is NFC.
Unused regunits are reserved so that verifier does not complain
about missing phys reg live-ins.
Differential Revision: https://reviews.llvm.org/D78591
Summary:
This seems like an obvious error - cut and paste issue?
The change does make a change to one of the lit tests - it stops s_buffer_load
re-ordering past an MUBUF instruction (which is not surprising).
Change-Id: I80be99de5b62af4f42e91af2591b76a52ac9efa6
Subscribers: arsenm, kzhuravl, jvesely, wdng, nhaehnle, yaxunl, tpr, t-tye, hiraditya, kerbowa, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D75686
Summary:
Making `Scale` a `TypeSize` in AArch64InstrInfo::getMemOpInfo,
has the effect that all places where this information is used
(notably, TargetInstrInfo::getMemOperandWithOffset) will need
to consider Scale - and derived, Offset - possibly being scalable.
This patch adds a new operand `bool &OffsetIsScalable` to
TargetInstrInfo::getMemOperandWithOffset and fixes up all
the places where this function is used, to consider the
offset possibly being scalable.
In most cases, this means bailing out because the algorithm does not
(or cannot) support scalable offsets in places where it does some
form of alias checking for example.
Reviewers: rovka, efriedma, kristof.beyls
Reviewed By: efriedma
Subscribers: wuzish, kerbowa, MatzeB, arsenm, nemanjai, jvesely, nhaehnle, hiraditya, kbarton, javed.absar, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, Jim, lenary, s.egerton, pzheng, sameer.abuasal, apazos, luismarques, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D72758
Based on D72931
This adds a new feature called A16 which is enabled for gfx10.
gfx9 keeps the R128A16 feature so it can share all the instruction encodings
with gfx7/8.
Differential Revision: https://reviews.llvm.org/D73956
We are using countPopulation on a LaneBitmask to determine
a number of registers it covers. This is the assumption which
does not necessarily need to be true. It is not changed but
factored into a single call SIRegisterInfo::getNumCoveredRegs().
Some other places are cleaned up with respect to assumptions
about subreg indexes values and tablegen behavior.
Differential Revision: https://reviews.llvm.org/D74177
SIMachineScheduler uses isHighLatencyInstruction with the same
sematincs, but TargetInstrInfo has virtual isHighLatencyDef
method, so override it instead.
Added FLAT to the list of high latency opcodes and a check for
mayLoad since stores are not technically high latency in terms
of data dependency.
This change did not produce any visible impact on our tests.
Differential Revision: https://reviews.llvm.org/D73582
Summary:
This removes a couple of unnecessary isReg checks, now that
memOpsHaveSameBasePtr can handle FI operands, but is otherwise NFC.
Reviewers: arsenm, rampitec
Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, kerbowa, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D73485
Summary:
This is in preparation for getMemOperandsWithOffset returning more base
operands.
Depends on D73455.
Reviewers: arsenm, rampitec
Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, kerbowa, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D73456
Summary:
This is in preparation for getMemOperandsWithOffset returning more base
operands.
Depends on D73454.
Reviewers: arsenm, rampitec
Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, kerbowa, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D73455
Scheduler sends NumLoads argument into shouldClusterMemOps()
one less the actual cluster length. So for 2 instructions
it will pass just 1. Correct this number.
This is NFC for in tree targets.
Differential Revision: https://reviews.llvm.org/D73292
We are relying on atrificial DAG edges inserted by the
MemOpClusterMutation to keep loads and stores together in the
post-RA scheduler. This does not work all the time since it
allows to schedule a completely independent instruction in the
middle of the cluster.
Removed the DAG mutation and added pass to bundle already
clustered instructions. These bundles are unpacked before the
memory legalizer because it does not work with bundles but also
because it allows to insert waitcounts in the middle of a store
cluster.
Removing artificial edges also allows a more relaxed scheduling.
Differential Revision: https://reviews.llvm.org/D72737
The generic BaseMemOpClusterMutation calls into TargetInstrInfo to
analyze the address of each load/store instruction, and again to decide
whether two instructions should be clustered. Previously this had to
represent each address as a single base operand plus a constant byte
offset. This patch extends it to support any number of base operands.
The old target hook getMemOperandWithOffset is now a convenience
function for callers that are only prepared to handle a single base
operand. It calls the new more general target hook
getMemOperandsWithOffset.
The only requirements for the base operands returned by
getMemOperandsWithOffset are:
- they can be sorted by MemOpInfo::Compare, such that clusterable ops
get sorted next to each other, and
- shouldClusterMemOps knows what they mean.
One simple follow-on is to enable clustering of AMDGPU FLAT instructions
with both vaddr and saddr (base register + offset register). I've left
a FIXME in the code for this case.
Differential Revision: https://reviews.llvm.org/D71655
In GlobalISel we may in some unfortunate circumstances generate PHIs with
operands that are on separate banks. If-conversion doesn't currently check for
that case and ends up generating a CSEL on AArch64 with incorrect register
operands.
Differential Revision: https://reviews.llvm.org/D72961
a785209bc2 switched to using a pseudos instead of manually tying
operands on the regular instruction. The VGPR indexing mode path
should have the same problems that change attempted to avoid, so these
should use the same strategy.
Use a single pseudo for the VGPR indexing mode and movreld paths, and
expand it based on the subtarget later. These have essentially the
same constraints, reading the index from m0.
Switch from using an offset to the subregister index directly, instead
of computing an offset and re-adding it back. Also add missing pseudos
for existing register class sizes.
We do not have InstrItinerary so generic getInstLatency() was always
defaulting to return 1 cycle. We need to use TargetSchedModel instead
to compute an instruction's latency.
Differential Revision: https://reviews.llvm.org/D72655
Summary:
The typo has been present since memOpsHaveSameBasePtr was introduced in
r313208.
It caused SIInstrInfo::shouldClusterMemOps to cluster more mem ops than
it was supposed to.
Subscribers: arsenm, kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D71616
This fixes an assertion failure that triggers inside
getMemOperandWithOffset when Machine Sinking calls it on a MachineInstr
that is not a memory operation.
Different backends implement getMemOperandWithOffset differently: some
return false on non-memory MachineInstrs, others assert.
The Machine Sinking pass in at least SinkingPreventsImplicitNullCheck
relies on getMemOperandWithOffset to return false on non-memory
MachineInstrs, instead of asserting.
This patch updates the documentation on getMemOperandWithOffset that it
should return false on any MachineInstr it cannot handle, instead of
asserting. It also adapts the in-tree backends accordingly where
necessary.
Differential Revision: https://reviews.llvm.org/D71359
Summary:
Pre gfx9 we need to scavenge a 64-bit SGPR to use as the carry out for an Add.
If only one SGPR was available this crashed when trying to scavenge another
32bit SGPR to materialize the offset.
Instead, reuse a 32-bit SGPR from the carry out as the offset register.
Also prefer to use vcc for the unused carry out when it is available.
Reviewers: arsenm, rampitec
Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D70614
These opcodes use indirect register addressing so they need special handling by codegen (currently missing).
Reviewers: vpykhtin, arsenm, rampitec
Differential Revision: https://reviews.llvm.org/D70400
The usage of target boolean checks is overly inflexible, since sext
and zext of a compare are equally cheap. The choice is arbitrary, but
using 0/1 to some degree is the choice of lower resistance since
that's what most targets use. This enables a few combines that don't
bother to support ZeroOrNegativeOneBooleanContent.
readlane and writelane instructions are not allowed to use m0 as the
data operand, so spilling them is tricky and would require an
intermediate SGPR to spill it. Constrain the virtual register class in
this caes to disallow the inline spiller from folding the m0 operand
directly into the spill instruction.
I copied this hack from AArch64 which has the same problem for $sp.
That used to fail in the last testcase function because after
%0:sreg_64.sub0 was folded into %3:sreg_32_xm0_xexec COPY, it
was further folded into S_STORE_DWORD_IMM. Its legal effective
subreg class is SReg_32 while instruction expects more restricted
SReg_32_XM0_EXEC. However, SIInstrInfo::isLegalRegOperand()
passed the legality check and it was caught in the verifier.
Borrowed code from the verifier to check for RC legality.
Differential Revision: https://reviews.llvm.org/D69445
Summary:
In loadSRsrcFromVGPR, if MBB is the same as Succ, Remiander is not the immediate dominator of Succ.
Reviewer:
arsenm
Differential Revision:
https://reviews.llvm.org/D69358
r375293 removed the SGPR spilling with scalar stores path, so this is
no longer necessary. This also always had the defect of adding the def
even when this path wasn't in use.
llvm-svn: 375448
If a PHI defines AGPR legalize its operands to AGPR.
At the moment we can get an AGPR PHI with VGPR operands.
I am not aware of any problems as it seems to be handled
gracefully in RA, but this is not right anyway.
It also slightly decreases VGPR pressure in some cases
because we do not have to a copy via VGPR.
Differential Revision: https://reviews.llvm.org/D69206
llvm-svn: 375446
We handle it this way for some other address spaces.
Since r349196, SILoadStoreOptimizer has been trying to do this. This
is after SIFoldOperands runs, which can change the addressing
patterns. It's simpler to just split this earlier.
llvm-svn: 375366
Mostly use SReg_32 instead of SReg_32_XM0 for arbitrary values. This
will allow the register coalescer to do a better job eliminating
copies to m0.
For GlobalISel, as a terrible hack, use SGPR_32 for things that should
use SCC until booleans are solved.
llvm-svn: 375267
Summary:
Even though writelane doesn't have the same constraints as other valu
instructions it still can't violate the >1 SGPR operand constraint
Due to later register propagation (e.g. fixing up vgpr operands via
readfirstlane) changing writelane to only have a single SGPR is tricky.
This implementation puts a new check after SIFixSGPRCopies that prevents
multiple SGPRs being used in any writelane instructions.
The algorithm used is to check for trivial copy prop of suitable constants into
one of the SGPR operands and perform that if possible. If this isn't possible
put an explicit copy of Src1 SGPR into M0 and use that instead (this is
allowable for writelane as the constraint is for SGPR read-port and not
constant-bus access).
Reviewers: rampitec, tpr, arsenm, nhaehnle
Reviewed By: rampitec, arsenm, nhaehnle
Subscribers: arsenm, kzhuravl, jvesely, wdng, nhaehnle, mgorny, yaxunl, tpr, t-tye, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D51932
Change-Id: Ic7553fa57440f208d4dbc4794fc24345d7e0e9ea
llvm-svn: 375004
Summary:
Two conditions could lead to infinite loops when processing PHI nodes in
SIFixSGPRCopies.
The first condition involves a REG_SEQUENCE that uses registers defined by both
a PHI and a COPY.
The second condition arises when a physical register is copied to a virtual
register which is then used in a PHI node. If the same virtual register is
copied to the same physical register, the result is an endless loop.
%0:sgpr_64 = COPY $sgpr0_sgpr1
%2 = PHI %0, %bb.0, %1, %bb.1
$sgpr0_sgpr1 = COPY %0
Reviewers: alex-t, rampitec, arsenm
Reviewed By: rampitec
Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68970
llvm-svn: 374944
We define mov/update dpp intrinsics as overloaded but do not
support i64, which is a practically useful type. Fix the
selection and lowering.
Differential Revision: https://reviews.llvm.org/D68673
llvm-svn: 374910
SGPR_128 only includes the real allocatable SGPRs, and SReg_128 adds
the additional non-allocatable TTMP registers. There's no point in
allocating SReg_128 vregs. This shrinks the size of the classes
regalloc needs to consider, which is usually good.
llvm-svn: 374284
Allows targets to introduce regbankselectable
pseudo-instructions. Currently the closet feature to this is an
intrinsic. However this requires creating a public intrinsic
declaration. This litters the public intrinsic namespace with
operations we don't necessarily want to expose to IR producers, and
would rather leave as private to the backend.
Use a new instruction bit. A previous attempt tried to keep using enum
value ranges, but it turned into a mess.
llvm-svn: 373937
When SIFixSGPRCopies attempts to fix an illegal copy from vector to
scalar register it calls moveToVALU(). A copy from an agpr to sgpr
becomes a copy from agpr to agpr, which may result in the illegal
register class at a use of this copy.
Solution is to copy it always into a vgpr. This may result in a
subsequent copy into an agpr if that is what really needed, however
should not happen too often and likely will be folded later.
The opposite situation may not happen because an sgpr is always
illegal where agpr is legal, so such user instructions may not
exist.
Differential Revision: https://reviews.llvm.org/D68358
llvm-svn: 373544
Summary:
Extend cachepolicy operand in the new VMEM buffer intrinsics
to supply information whether the buffer data is swizzled.
Also, propagate this information to MIR.
Intrinsics updated:
int_amdgcn_raw_buffer_load
int_amdgcn_raw_buffer_load_format
int_amdgcn_raw_buffer_store
int_amdgcn_raw_buffer_store_format
int_amdgcn_raw_tbuffer_load
int_amdgcn_raw_tbuffer_store
int_amdgcn_struct_buffer_load
int_amdgcn_struct_buffer_load_format
int_amdgcn_struct_buffer_store
int_amdgcn_struct_buffer_store_format
int_amdgcn_struct_tbuffer_load
int_amdgcn_struct_tbuffer_store
Furthermore, disable merging of VMEM buffer instructions
in SI Load/Store optimizer, if the "swizzled" bit on the instruction
is on.
The default value of the bit is 0, meaning that data in buffer
is linear and buffer instructions can be merged.
There is no difference in the generated code with this commit.
However, in the future it will be expected that front-ends
use buffer intrinsics with correct "swizzled" bit set.
Reviewers: arsenm, nhaehnle, tpr
Reviewed By: nhaehnle
Subscribers: arsenm, kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, arphaman, jfb, Petar.Avramovic, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68200
llvm-svn: 373491
Neither the base implementation of findCommutedOpIndices nor any in-tree target modifies the instruction passed in and there is no reason why they would in the future.
Committed on behalf of @hvdijk (Harald van Dijk)
Differential Revision: https://reviews.llvm.org/D66138
llvm-svn: 372882
This was relying on the SGPR usable for the carry out clobber to also
be used for the input. There was no carry out on gfx9. With no carry
out clobber to worry about, so the literal can just be directly used
with a VOP2 add.
llvm-svn: 371791
Since an add instruction must produce an unused carry out, this
requires additional SGPRs. This can be avoided by keeping the entire
offset computation in SGPRs. If one SGPR is still available, this only
costs one extra mov. If none are available, the entire computation can
be done in place and reversed.
This does assume the use is a VGPR operand. This was already assumed,
and we currently only select frame indexes to VALU instructions. This
should probably be fixed at some point to handle more possible MIR.
llvm-svn: 370929
SGPR spills aren't really handled after SILowerSGPRSpills. In order to
directly control what happens if the scavenger needs to spill, the
scavenger needs to be used directly. There is an alternative to
spilling in these contexts anyway since the frame register can be
increment and restored.
This does present another possible issue if spilling is needed for the
unused carry out if an add is needed. I think this can be avoided by
using a scalar add (although that clobbers SCC, which happens anyway).
llvm-svn: 370281
Summary:
This clang-tidy check is looking for unsigned integer variables whose initializer
starts with an implicit cast from llvm::Register and changes the type of the
variable to llvm::Register (dropping the llvm:: where possible).
Partial reverts in:
X86FrameLowering.cpp - Some functions return unsigned and arguably should be MCRegister
X86FixupLEAs.cpp - Some functions return unsigned and arguably should be MCRegister
X86FrameLowering.cpp - Some functions return unsigned and arguably should be MCRegister
HexagonBitSimplify.cpp - Function takes BitTracker::RegisterRef which appears to be unsigned&
MachineVerifier.cpp - Ambiguous operator==() given MCRegister and const Register
PPCFastISel.cpp - No Register::operator-=()
PeepholeOptimizer.cpp - TargetInstrInfo::optimizeLoadInstr() takes an unsigned&
MachineTraceMetrics.cpp - MachineTraceMetrics lacks a suitable constructor
Manual fixups in:
ARMFastISel.cpp - ARMEmitLoad() now takes a Register& instead of unsigned&
HexagonSplitDouble.cpp - Ternary operator was ambiguous between unsigned/Register
HexagonConstExtenders.cpp - Has a local class named Register, used llvm::Register instead of Register.
PPCFastISel.cpp - PPCEmitLoad() now takes a Register& instead of unsigned&
Depends on D65919
Reviewers: arsenm, bogner, craig.topper, RKSimon
Reviewed By: arsenm
Subscribers: RKSimon, craig.topper, lenary, aemerson, wuzish, jholewinski, MatzeB, qcolombet, dschuff, jyknight, dylanmckay, sdardis, nemanjai, jvesely, wdng, nhaehnle, sbc100, jgravelle-google, kristof.beyls, hiraditya, aheejin, kbarton, fedor.sergeev, javed.absar, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, tpr, PkmX, jocewei, jsji, Petar.Avramovic, asbirlea, Jim, s.egerton, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65962
llvm-svn: 369041
Add llvm.amdgcn.softwqm intrinsic which behaves like llvm.amdgcn.wqm
only if there is other WQM computation in the shader.
Reviewers: nhaehnle, tpr
Reviewed By: nhaehnle
Subscribers: arsenm, kzhuravl, jvesely, wdng, yaxunl, dstuttard, t-tye, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64935
llvm-svn: 367097
Now that the patterns use the new PatFrag address space support, the
only blocker to importing most load patterns is the addressing mode
complex patterns.
llvm-svn: 366237
Summary:
r363675 changed the exec modification helper function, now called
execMayBeModifiedBeforeUse, so that if no UseMI is specified it checks
all instructions in the basic block, even beyond the last use. That
meant that the DPP combiner no longer worked in any basic block that
ended with a control flow instruction, and in particular it didn't work
on code sequences generated by the atomic optimizer.
Fix it by reinstating the old behaviour but in a new helper function
execMayBeModifiedBeforeAnyUse, and limiting the number of instructions
scanned.
Reviewers: arsenm, vpykhtin
Subscribers: kzhuravl, nemanjai, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, kbarton, MaskRay, jfb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64393
llvm-svn: 365910
Make the FP register callee saved.
This is tricky because now the FP needs to be spilled in the prolog
relative to the incoming SP register, rather than the frame register
used throughout the rest of the function. I don't like how this
bypassess the standard mechanism for CSR spills just to get the
correct insert point. I may look for a better solution, since all CSR
VGPRs may also need to have all lanes activated. Another option might
be to make getFrameIndexReference change the base register if the
frame index is a CSR, and then try to figure out the right insertion
point in emitProlog.
If there is a free VGPR lane available for SGPR spilling, try to use
it for the FP. If that would require intrtoducing a new VGPR spill,
try to use a free call clobbered SGPR. Only fallback to introducing a
new VGPR spill as a last resort.
This also doesn't attempt to handle SGPR spilling with scalar stores.
llvm-svn: 365372
Summary:
The stride should depend on the wave size, not the hardware generation.
Also, the 32_FLOAT format is 0x16, not 16; though that shouldn't be
relevant.
Change-Id: I088f93bf6708974d085d1c50967f119061da6dc6
Reviewers: arsenm, rampitec, mareko
Subscribers: kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, t-tye, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D63808
llvm-svn: 364788
Summary:
The symbols use the processor-specific SHN_AMDGPU_LDS section index
introduced with a previous change. The linker is then expected to resolve
relocations, which are also emitted.
Initially disabled for HSA and PAL environments until they have caught up
in terms of linker and runtime loader.
Some notes:
- The llvm.amdgcn.groupstaticsize intrinsics can no longer be lowered
to a constant at compile times, which means some tests can no longer
be applied.
The current "solution" is a terrible hack, but the intrinsic isn't
used by Mesa, so we can keep it for now.
- We no longer know the full LDS size per kernel at compile time, which
means that we can no longer generate a relevant error message at
compile time. It would be possible to add a check for the size of
individual variables, but ultimately the linker will have to perform
the final check.
Change-Id: If66dbf33fccfbf3609aefefa2558ac0850d42275
Reviewers: arsenm, rampitec, t-tye, b-sumner, jsjodin
Subscribers: qcolombet, kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D61494
llvm-svn: 364297
Introducing VCC defs during SIFixSGPRCopies is generally
problematic. Avoid it by starting with the VOP3 form with the general
condition register. This is the easiest to fix instance, but doesn't
solve any specific problems I'm looking at.
llvm-svn: 363904
This is incomplete, and ideally these would all be removed, but it's
better to localize them to the subtarget first with comments about
what they're for.
llvm-svn: 363902
The def instruction for the vreg may not match, because it may be
folding through a reg_sequence. The assert was overly conservative and
not necessary. It's not actually important if DefMI really defined the
register, because the fold that will be done cares about the def of
the value that will be folded.
For some reason copies aren't making it through the reg_sequence,
although they should.
llvm-svn: 363876
This reapplies r363678, using the correct chain for the CopyToReg for
v0. glueCopyToM0 counterintuitively changes the operands of the
original node.
llvm-svn: 363870
Invert the name and return value to better reflect the imprecise
nature.
Force passing in the DefMI, since it's known in the 2 users and could
possibly fail for an arbitrary vreg.
Allow specifying a specific user instruction. Scan through use
instructions, instead of use operands. Add scan thresholds instead of
searching infinitely.
Stop using a set to track seen uses. I didn't understand this usage,
or why it would not check the last use. I don't think the use list has
any particular order.
llvm-svn: 363675
This patch changes MIR stack-id from an integer to an enum,
and adds printing/parsing support for this in MIR files. The default
stack-id '0' is now renamed to 'default'.
This should make MIR tests that have stack objects with different stack-ids
more descriptive. It also clarifies code operating on StackID.
Reviewers: arsenm, thegameg, qcolombet
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D60137
llvm-svn: 363533
Summary:
Instead of encoding a high-word of 0 using a fake TargetGlobalAddress,
just use a literal target constant. This simplifies some subsequent changes.
The generated assembly is now more explicit about the kind of relocation
that is to be used.
Change-Id: I066835202d23b5941fa7a358eb4b89e9b71ab6f8
Reviewers: arsenm, rampitec
Subscribers: kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, t-tye, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D61491
llvm-svn: 363516
SIInsertSkips really doesn't understand the control flow, and makes
very stupid assumptions about the block layout. This was able to get
away with not skipping return blocks, since usually after
structurization there is only one placed at the end of the
function. Tail duplication can break this assumption.
llvm-svn: 362754
"Divergence driven ISel. Assign register class for cross block values
according to the divergence."
that discovered the design flaw leading to several issues that
required to be solved before.
This change reverts AMDGPU specific changes and keeps common part
unaffected.
llvm-svn: 362749
Since the beginning, the offset of a frame index has been consistently
interpreted backwards. It was treating it as an offset from the
scratch wave offset register as a frame register. The correct
interpretation is the offset from the SP on entry to the function,
before the prolog. Frame index elimination then should select either
SP or another register as an FP.
Treat the scratch wave offset on kernel entry as the pre-incremented
SP. Rely more heavily on the standard hasFP and frame pointer
elimination logic, and clean up the private reservation code. This
saves a copy in most callee functions.
The kernel prolog emission code is still kind of a mess relying on
checking the uses of physical registers, which I would prefer to
eliminate.
Currently selection directly emits MUBUF instructions, which require
using a reference to some register. Use the register chosen for SP,
and then ignore this later. This should probably be cleaned up to use
pseudos that don't refer to any specific base register until frame
index elimination.
Add a workaround for shaders using large numbers of SGPRs. I'm not
sure these cases were ever working correctly, since as far as I can
tell the logic for figuring out which SGPR is the scratch wave offset
doesn't match up with the shader input initialization in the shader
programming guide.
llvm-svn: 362661
Details: To make instruction selection really divergence driven it is necessary to assign
the correct register classes to the cross block values beforehand. For the divergent targets
same value type requires different register classes dependent on the value divergence.
Reviewers: rampitec, nhaehnle
Differential Revision: https://reviews.llvm.org/D59990
This commit was reverted because of the build failure.
The reason was mlformed patch.
Build failure fixed.
llvm-svn: 361741
Details: To make instruction selection really divergence driven it is necessary to assign
the correct register classes to the cross block values beforehand. For the divergent targets
same value type requires different register classes dependent on the value divergence.
Reviewers: rampitec, nhaehnle
Differential Revision: https://reviews.llvm.org/D59990
llvm-svn: 361644
Keep it optional in cases this is ever needed in some global
context. Currently it's only used for getting an upper bound inline
asm code size.
For AMDGPU, gfx10 increases the maximum instruction size to
20-bytes. This avoids penalizing older subtargets when estimating code
size, and making some annoying branch relaxation test adjustments.
llvm-svn: 361405
Unfortunately the way SIInsertSkips works is backwards, and is
required for correctness. r338235 added handling of some special cases
where skipping is mandatory to avoid side effects if no lanes are
active. It conservatively handled asm correctly, but the same logic
needs to apply to calls.
Usually the call sequence code is larger than the skip threshold,
although the way the count is computed is really broken, so I'm not
sure if anything was likely to really hit this.
llvm-svn: 361202
Summary:
No test case because I don't know of a way to trigger this, but I
accidentally caused this to fail while working on a different change.
Change-Id: I8015aa447fe27163cc4e4902205a203bd44bf7e3
Reviewers: arsenm, rampitec
Subscribers: kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, t-tye, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D61490
llvm-svn: 360123