AMDGPU: Directly implement computeKnownBits for workitem intrinsics

Currently metadata is inserted in a late pass which is lowered
to an AssertZext. The metadata would be more useful if it was
inser

AMDGPU: Directly implement computeKnownBits for workitem intrinsics

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.

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[AMDGPU] Make enable-flat-scratch a subtarget feature

Use a subtarget feature instead of a command line argument to reduce
global state.
We want to enable flat scratch for graphics in some cases and

[AMDGPU] Make enable-flat-scratch a subtarget feature

Use a subtarget feature instead of a command line argument to reduce
global state.
We want to enable flat scratch for graphics in some cases and this
doesn't work well with command line options.

Differential Revision: https://reviews.llvm.org/D119425

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[LSV] Vectorize loads of vectors by turning it into a larger vector

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

[LSV] Vectorize loads of vectors by turning it into a larger vector

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

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AMDGPU: Enable fixed function ABI by default

Code using indirect calls is broken without this, and there isn't
really much value in supporting the old attempt to vary the argument
placement based on

AMDGPU: Enable fixed function ABI by default

Code using indirect calls is broken without this, and there isn't
really much value in supporting the old attempt to vary the argument
placement based on uses. This resulted in more argument shuffling code
anyway.

Also have the option stop implying all inputs need to be passed. This
will no rely on the amdgpu-no-* attributes to avoid passing
unnecessary values.

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[AMDGPU] Set most sched model resource's BufferSize to one

Using a BufferSize of one for memory ProcResources will result in better
ILP since it more accurately models the dependencies between memor

[AMDGPU] Set most sched model resource's BufferSize to one

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

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[AMDGPU] Only allow implicit WQM in pixel shaders

Implicit derivatives are only valid in pixel shaders,
hence only implicitly enable WQM for pixel shaders.
This avoids unintended WQM in other shader

[AMDGPU] Only allow implicit WQM in pixel shaders

Implicit derivatives are only valid in pixel shaders,
hence only implicitly enable WQM for pixel shaders.
This avoids unintended WQM in other shader types (e.g. compute)
when image sampling instructions are used.

Reviewed By: rampitec

Differential Revision: https://reviews.llvm.org/D114414

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[AMDGPU] Switch PostRA sched to MachineSched

Use GCNHazardRecognizer in postra sched.
Updated tests for the new schedules.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D1095

[AMDGPU] Switch PostRA sched to MachineSched

Use GCNHazardRecognizer in postra sched.
Updated tests for the new schedules.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D109536

Change-Id: Ia86ba2ae168f12fb34b4d8efdab491f84d936cde

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[AMDGPU] Init scratch only if necessary

If no scratch or flat instructions are used, we do not need to
initialize the flat scratch hardware register.

Differential Revision: https://reviews.llvm.org

[AMDGPU] Init scratch only if necessary

If no scratch or flat instructions are used, we do not need to
initialize the flat scratch hardware register.

Differential Revision: https://reviews.llvm.org/D105920

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[AMDGPU] Experiments show that the GCNRegBankReassign pass significantly impacts
the compilation time and there is no case for which we see any improvement in
performance. This patch removes this pas

[AMDGPU] Experiments show that the GCNRegBankReassign pass significantly impacts
the compilation time and there is no case for which we see any improvement in
performance. This patch removes this pass and its associated test cases from
the tree.

Differential Revision: https://reviews.llvm.org/D101313

Change-Id: I0599169a7609c19a887f8d847a71e664030cc141

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AMDGPU: Use kill instruction to hint soft clause live ranges

Previously we would use a bundle to hint the register allocator to not
overwrite the pointers in a sequence of loads to avoid breaking so

AMDGPU: Use kill instruction to hint soft clause live ranges

Previously we would use a bundle to hint the register allocator to not
overwrite the pointers in a sequence of loads to avoid breaking soft
clauses. This bundling was based on a fuzzy register pressure
heuristic, so we could not guarantee using more registers than are
really available. This would result in register allocator failing on
unsatisfiable bundles. Use a kill to artificially extend the live
ranges, so we can always succeed at register allocation even if it
means extra spills in the worst case.

This seems to capture most of the benefit of the bundle while avoiding
most of the risk presented by the bundle. However the lit tests do
show a handful of regressions. In some cases with sequences of
volatile loads, unused load components end up getting reallocated to
the next load which forces a wait between. There are also a few small
scheduling regressions where a hazard used to be avoided, and one
spill torture test which for some reason nearly doubles the stack
usage. There is also a bit of noise from leftover kills (it may make
sense for post-RA pseudos to strip all of these out).

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[AMDGPU] Fix failing assert with scratch ST mode

In ST mode, flat scratch instructions have neither an sgpr nor a vgpr
for the address. This lead to an assertion when inserting hard clauses.

Differ

[AMDGPU] Fix failing assert with scratch ST mode

In ST mode, flat scratch instructions have neither an sgpr nor a vgpr
for the address. This lead to an assertion when inserting hard clauses.

Differential Revision: https://reviews.llvm.org/D94406

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AMDGPU: Select global saddr mode from SGPR pointer

Use the 64-bit SGPR base with a 0 offset, since it's 1 fewer
instruction to materialize the 0 vs. the 64-bit copy.

[amdgpu] Enable use of AA during codegen.

- Add an internal option `-amdgpu-use-aa-in-codegen` to enable or
disable this feature. By Default, it's enabled.

Differential Revision: https://reviews.

[amdgpu] Enable use of AA during codegen.

- Add an internal option `-amdgpu-use-aa-in-codegen` to enable or
disable this feature. By Default, it's enabled.

Differential Revision: https://reviews.llvm.org/D89320

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[AMDGPU] Avoid inserting noops during scheduling

Passes that are run after the post-RA scheduler may insert instructions like
waitcnt which eliminate the need for certain noops. After this patch the

[AMDGPU] Avoid inserting noops during scheduling

Passes that are run after the post-RA scheduler may insert instructions like
waitcnt which eliminate the need for certain noops. After this patch the
scheduler is still aware of possible latency from hazards but noops will
not be inserted until the dedicated hazard recognizer pass is run.

Depends on D89753.

Reviewed By: foad

Differential Revision: https://reviews.llvm.org/D89754

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Revert "[AMDGPU] Insert waitcnt after returning from call"

This reverts commit ca907bfb57d8ad3ec3bcc2cff2abab7b1b933af6.

According to michel.daenzer,
> This completely broke the Mesa radeonsi drive

Revert "[AMDGPU] Insert waitcnt after returning from call"

This reverts commit ca907bfb57d8ad3ec3bcc2cff2abab7b1b933af6.

According to michel.daenzer,
> This completely broke the Mesa radeonsi driver on Navi 14. Xorg +
> xterm come up with major corruption & psychedelic colours.

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[AMDGPU] Insert waitcnt after returning from call

When memory operations are outstanding on function calls, either the
caller or the callee can insert a waitcnt to ensure that all reads are
finished

[AMDGPU] Insert waitcnt after returning from call

When memory operations are outstanding on function calls, either the
caller or the callee can insert a waitcnt to ensure that all reads are
finished.
Calls need some time to be executed, so if the callee inserts the
waitcnt, filling the instruction buffer and waiting for memory will be
interleaved, hiding some latency. This comes at the cost of having a
waitcnt inside functions that may not be needed as no memory operations
are outstanding.

For function calls, this is already implemented. The same principal
applies to returns: If the caller inserts a waitcnt after the call, the
callee does not have to wait and the return and memory operation can be
run in parallel.

This commit implements waiting in the caller after returning from a
function call.

Differential Revision: https://reviews.llvm.org/D87674

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[AMDGPU] Don't cluster stores

Clustering loads has caching benefits, but as far as I know there is no
advantage to clustering stores on any AMDGPU subtargets.

The disadvantage is that it tends to i

[AMDGPU] Don't cluster stores

Clustering loads has caching benefits, but as far as I know there is no
advantage to clustering stores on any AMDGPU subtargets.

The disadvantage is that it tends to increase register pressure and
restricts scheduling freedom.

Differential Revision: https://reviews.llvm.org/D85530

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AMDGPU: Match global saddr addressing mode

The previous implementation was incorrect, and based off incorrect
instruction definitions. Unfortunately we can't match natural
addressing in a lot of cas

AMDGPU: Match global saddr addressing mode

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.

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AMDGPU: Remove SIFixupVectorISel pass

This was only used for matching the saddr addressing mode of global
instructions, but this was not implemented correctly. The instruction
definitions aren't eve

AMDGPU: Remove SIFixupVectorISel pass

This was only used for matching the saddr addressing mode of global
instructions, but this was not implemented correctly. The instruction
definitions aren't even correct, and are defined as using a 64-bit
VGPR component. Eliminate this pass to enable correcting the
instruction definitions. A new matching implementation can work in
GlobalISel or relying on DAG divergence information for the base
address.

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[MachineScheduler] Fix the TopDepth/BotHeightReduce latency heuristics

tryLatency compares two sched candidates. For the top zone it prefers
the one with lesser depth, but only if that depth is grea

[MachineScheduler] Fix the TopDepth/BotHeightReduce latency heuristics

tryLatency compares two sched candidates. For the top zone it prefers
the one with lesser depth, but only if that depth is greater than the
total latency of the instructions we've already scheduled -- otherwise
its latency would be hidden and there would be no stall.

Unfortunately it only tests the depth of one of the candidates. This can
lead to situations where the TopDepthReduce heuristic does not kick in,
but a lower priority heuristic chooses the other candidate, whose depth
*is* greater than the already scheduled latency, which causes a stall.

The fix is to apply the heuristic if the depth of *either* candidate is
greater than the already scheduled latency.

All this also applies to the BotHeightReduce heuristic in the bottom
zone.

Differential Revision: https://reviews.llvm.org/D72392

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Revert "[AMDGPU/MemOpsCluster] Implement new heuristic for computing max mem ops cluster size"

This reverts commit cc9d69385659be32178506a38b4f2e112ed01ad4.

[AMDGPU/MemOpsCluster] Implement new heuristic for computing max mem ops cluster size

Summary:
Make use of both the - (1) clustered bytes and (2) cluster length, to decide on
the max number of mem o

[AMDGPU/MemOpsCluster] Implement new heuristic for computing max mem ops cluster size

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

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Revert "[AMDGPU/MemOpsCluster] Implement new heuristic for computing max mem ops cluster size"

This reverts commit 40a632a335119fe3e8d5d500a5d2641998314ecb.

[AMDGPU/MemOpsCluster] Implement new heuristic for computing max mem ops cluster size

Summary:
Make use of both the - (1) clustered bytes and (2) cluster length, to decide on
the max number of mem o

[AMDGPU/MemOpsCluster] Implement new heuristic for computing max mem ops cluster size

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

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[AMDGPU] Better support for VMEM soft clauses in GCNHazardRecognizer

VMEM soft clauses only contain VMEM and FLAT instructions. Teaching
GCNHazardRecognizer::checkSoftClauseHazards that other kinds

[AMDGPU] Better support for VMEM soft clauses in GCNHazardRecognizer

VMEM soft clauses only contain VMEM and FLAT instructions. Teaching
GCNHazardRecognizer::checkSoftClauseHazards that other kinds of
instructions will naturally break the clause means there are far fewer
cases where it has to insert an s_nop instruction to forcibly break the
clause.

Differential Revision: https://reviews.llvm.org/D79353

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