[AMDGPU] Simplify AMDGPUAnnotateUniformValues::visitLoadInst

Always set uniform metadata on the pointer if it is an instruction, but
otherwise do not bother to create a trivial getelementptr instruc

[AMDGPU] Simplify AMDGPUAnnotateUniformValues::visitLoadInst

Always set uniform metadata on the pointer if it is an instruction, but
otherwise do not bother to create a trivial getelementptr instruction,
because AMDGPUInstrInfo::isUniformMMO can already detect that various
non-instruction pointers are uniform.

Most of the test case churn is from tests that used undef as a pointer,
which AMDGPUInstrInfo::isUniformMMO treats as uniform.

Differential Revision: https://reviews.llvm.org/D118909

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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] Do not generate ELF symbols for the local branch target labels

The compiler was generating symbols in the final code object for local
branch target labels. This bloats the code object, slow

[AMDGPU] Do not generate ELF symbols for the local branch target labels

The compiler was generating symbols in the final code object for local
branch target labels. This bloats the code object, slows down the loader,
and is only used to simplify disassembly.

Use '--symbolize-operands' with llvm-objdump to improve readability of the
branch target operands in disassembly.

Fixes: SWDEV-312223

Reviewed By: scott.linder

Differential Revision: https://reviews.llvm.org/D114273

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[AMDGPU] Divergence-driven compare operations instruction selection

Description: This change enables the compare operations to be selected to SALU/VALU form
dependent of the SDNode dive

[AMDGPU] Divergence-driven compare operations instruction selection

Description: This change enables the compare operations to be selected to SALU/VALU form
dependent of the SDNode divergence flag.

Reviewed By: rampitec

Differential Revision: https://reviews.llvm.org/D106079

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AMDGPU: Add alloc priority to global ranges

The requested register class priorities weren't respected
globally. Not sure why this is a target option, and not just the
expected behavior (recently add

AMDGPU: Add alloc priority to global ranges

The requested register class priorities weren't respected
globally. Not sure why this is a target option, and not just the
expected behavior (recently added in
1a6dc92be7d68611077f0fb0b723b361817c950c). This avoids an allocation
failure when many wide tuple spills are introduced. I think this is a
workaround since I would not expect the allocation priority to be
required, and only a performance hint. The allocator should be smarter
about when only a subregister needs to be spilled and restored.

This does regress a couple of degenerate store stress lit tests which
shouldn't be too important.

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[AMDGPU] Add volatile support to SIMemoryLegalizer

Treat a non-atomic volatile load and store as a relaxed atomic at
system scope for the address spaces accessed. This will ensure all
relevant cache

[AMDGPU] Add volatile support to SIMemoryLegalizer

Treat a non-atomic volatile load and store as a relaxed atomic at
system scope for the address spaces accessed. This will ensure all
relevant caches will be bypassed.

A volatile atomic is not changed and still only bypasses caches upto
the level specified by the SyncScope operand.

Differential Revision: https://reviews.llvm.org/D94214

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[AMDGPU] Fix and extend vccz workarounds

We have workarounds for two different cases where vccz can get out of
sync with the value in vcc. This fixes them in two ways:

1. Fix the case where the def

[AMDGPU] Fix and extend vccz workarounds

We have workarounds for two different cases where vccz can get out of
sync with the value in vcc. This fixes them in two ways:

1. Fix the case where the def of vcc was in a previous basic block, by
pessimistically assuming that vccz might be incorrect at a basic block
boundary.

2. Fix the handling of pre-existing waitcnt instructions by calling
generateWaitcntInstBefore before examining ScoreBrackets to determine
whether there's an outstanding smem read operation.

Differential Revision: https://reviews.llvm.org/D91636

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[Sink] Optimize/simplify sink candidate finding with nearest common dominator

For an instruction in the basic block BB, SinkingPass enumerates basic blocks
dominated by BB and BB's successors. For e

[Sink] Optimize/simplify sink candidate finding with nearest common dominator

For an instruction in the basic block BB, SinkingPass enumerates basic blocks
dominated by BB and BB's successors. For each enumerated basic block,
SinkingPass uses `AllUsesDominatedByBlock` to check whether the basic
block dominates all of the instruction's users. This is inefficient.

Use the nearest common dominator of all users to avoid enumerating the
candidate. The nearest common dominator may be in a parent loop which is
not beneficial. In that case, find the ancestors in the dominator tree.

In the case that the instruction has no user, with this change we will
not perform unnecessary move. This causes some amdgpu test changes.

A stage-2 x86-64 clang is a byte identical with this change.

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Revert "[AMDGPU] Enable compare operations to be selected by divergence"

This reverts commit 521ac0b5cea02f629d035f807460affbb65ae7ad.

Reported to break thousands of piglit tests.

[AMDGPU] Enable compare operations to be selected by divergence

Summary: Details: This patch enables SETCC to be selected to S_CMP_* if uniform and V_CMP_* if divergent.

Reviewers: rampitec, arsenm

[AMDGPU] Enable compare operations to be selected by divergence

Summary: Details: This patch enables SETCC to be selected to S_CMP_* if uniform and V_CMP_* if divergent.

Reviewers: rampitec, arsenm

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/D82194

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[AMDGPU] Enable structurizer workarounds by default

Reviewed By: nhaehnle

Differential Revision: https://reviews.llvm.org/D81211

[AMDGPU] Disable 'Skip Uniform Regions' optimization by default for AMDGPU.

Reviewers: sameerds, dstuttard

Differential Revision: https://reviews.llvm.org/D77228

Revert e1730cfeb3588f20dcf4a96b181ad52761666e52

[AMDGPU] Disable 'Skip Uniform Regions' optimization by default for AMDGPU.

Reviewers: sameerds, dstuttard

Differential Revision: https://reviews.llvm.org/D77228

[AMDGPU] add generated checks for some LIT tests

This is in prepration for further changes that affect these tests.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D75403

[AMDGPU] Fix emitIfBreak CF lowering: use temp reg to make register coalescer life easier.

Differential revision: https://reviews.llvm.org/D70405

[AMDGPU] Come back patch for the 'Assign register class for cross block values according to the divergence.'

Detailed description:

After https://reviews.llvm.org/D59990 submit several issues

[AMDGPU] Come back patch for the 'Assign register class for cross block values according to the divergence.'

Detailed description:

After https://reviews.llvm.org/D59990 submit several issues were discovered.
Changes in common code were preserved but AMDGPU specific part was reverted to keep the backend working correctly.

Discovered issues were addressed in the following commits:

https://reviews.llvm.org/D67662
https://reviews.llvm.org/D67101
https://reviews.llvm.org/D63953
https://reviews.llvm.org/D63731

This change brings back AMDGPU specific changes.

Reviewed by: rampitec, arsenm

Differential Revision: https://reviews.llvm.org/D68635

llvm-svn: 374767

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Revert [MBP] Disable aggressive loop rotate in plain mode

This reverts r369664 (git commit 51f48295cbe8fa3a44db263b528dd9f7bae7bf9a)

It causes many benchmark regressions, internally and in llvm's b

Revert [MBP] Disable aggressive loop rotate in plain mode

This reverts r369664 (git commit 51f48295cbe8fa3a44db263b528dd9f7bae7bf9a)

It causes many benchmark regressions, internally and in llvm's benchmark suite.

llvm-svn: 370398

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[MBP] Disable aggressive loop rotate in plain mode

Patch https://reviews.llvm.org/D43256 introduced more aggressive loop layout optimization which depends on profile information. If profile informat

[MBP] Disable aggressive loop rotate in plain mode

Patch https://reviews.llvm.org/D43256 introduced more aggressive loop layout optimization which depends on profile information. If profile information is not available, the statically estimated profile information(generated by BranchProbabilityInfo.cpp) is used. If user program doesn't behave as BranchProbabilityInfo.cpp expected, the layout may be worse.

To be conservative this patch restores the original layout algorithm in plain mode. But user can still try the aggressive layout optimization with -force-precise-rotation-cost=true.

Differential Revision: https://reviews.llvm.org/D65673

llvm-svn: 369664

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Revert r368339 "[MBP] Disable aggressive loop rotate in plain mode"

It caused assertions to fire when building Chromium:

lib/CodeGen/LiveDebugValues.cpp:331: bool
{anonymous}::LiveDebugValues::

Revert r368339 "[MBP] Disable aggressive loop rotate in plain mode"

It caused assertions to fire when building Chromium:

lib/CodeGen/LiveDebugValues.cpp:331: bool
{anonymous}::LiveDebugValues::OpenRangesSet::empty() const: Assertion
`Vars.empty() == VarLocs.empty() && "open ranges are inconsistent"' failed.

See https://crbug.com/992871#c3 for how to reproduce.

> Patch https://reviews.llvm.org/D43256 introduced more aggressive loop layout optimization which depends on profile information. If profile information is not available, the statically estimated profile information(generated by BranchProbabilityInfo.cpp) is used. If user program doesn't behave as BranchProbabilityInfo.cpp expected, the layout may be worse.
>
> To be conservative this patch restores the original layout algorithm in plain mode. But user can still try the aggressive layout optimization with -force-precise-rotation-cost=true.
>
> Differential Revision: https://reviews.llvm.org/D65673

llvm-svn: 368579

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[MBP] Disable aggressive loop rotate in plain mode

Patch https://reviews.llvm.org/D43256 introduced more aggressive loop layout optimization which depends on profile information. If profile informat

[MBP] Disable aggressive loop rotate in plain mode

Patch https://reviews.llvm.org/D43256 introduced more aggressive loop layout optimization which depends on profile information. If profile information is not available, the statically estimated profile information(generated by BranchProbabilityInfo.cpp) is used. If user program doesn't behave as BranchProbabilityInfo.cpp expected, the layout may be worse.

To be conservative this patch restores the original layout algorithm in plain mode. But user can still try the aggressive layout optimization with -force-precise-rotation-cost=true.

Differential Revision: https://reviews.llvm.org/D65673

llvm-svn: 368339

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[MBP] Move a latch block with conditional exit and multi predecessors to top of loop

Current findBestLoopTop can find and move one kind of block to top, a latch block has one successor. Another comm

[MBP] Move a latch block with conditional exit and multi predecessors to top of loop

Current findBestLoopTop can find and move one kind of block to top, a latch block has one successor. Another common case is:

* a latch block
* it has two successors, one is loop header, another is exit
* it has more than one predecessors

If it is below one of its predecessors P, only P can fall through to it, all other predecessors need a jump to it, and another conditional jump to loop header. If it is moved before loop header, all its predecessors jump to it, then fall through to loop header. So all its predecessors except P can reduce one taken branch.

Differential Revision: https://reviews.llvm.org/D43256

llvm-svn: 363471

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[MBP] Don't move bottom block before header if it can't reduce taken branches

If bottom of block BB has only one successor OldTop, in most cases it is profitable to move it before OldTop, except the

[MBP] Don't move bottom block before header if it can't reduce taken branches

If bottom of block BB has only one successor OldTop, in most cases it is profitable to move it before OldTop, except the following case:

-->OldTop<-
| . |
| . |
| . |
---Pred |
| |
BB-----

Move BB before OldTop can't reduce the number of taken branches, this patch detects this case and prevent the moving.

Differential Revision: https://reviews.llvm.org/D57067

llvm-svn: 352236

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AMDGPU: Rewrite SILowerI1Copies to always stay on SALU

Summary:
Instead of writing boolean values temporarily into 32-bit VGPRs
if they are involved in PHIs or are observed from outside a loop,
we u

AMDGPU: Rewrite SILowerI1Copies to always stay on SALU

Summary:
Instead of writing boolean values temporarily into 32-bit VGPRs
if they are involved in PHIs or are observed from outside a loop,
we use bitwise masking operations to combine lane masks in a way
that is consistent with wave control flow.

Move SIFixSGPRCopies to before this pass, since that pass
incorrectly attempts to move SGPR phis to VGPRs.

This should recover most of the code quality that was lost with
the bug fix in "AMDGPU: Remove PHI loop condition optimization".

There are still some relevant cases where code quality could be
improved, in particular:

- We often introduce redundant masks with EXEC. Ideally, we'd
have a generic computeKnownBits-like analysis to determine
whether masks are already masked by EXEC, so we can avoid this
masking both here and when lowering uniform control flow.

- The criterion we use to determine whether a def is observed
from outside a loop is conservative: it doesn't check whether
(loop) branch conditions are uniform.

Change-Id: Ibabdb373a7510e426b90deef00f5e16c5d56e64b

Reviewers: arsenm, rampitec, tpr

Subscribers: kzhuravl, jvesely, wdng, mgorny, yaxunl, dstuttard, t-tye, eraman, llvm-commits

Differential Revision: https://reviews.llvm.org/D53496

llvm-svn: 345719

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[AMDGPU] Enable LICM in the BE pipeline

This allows to hoist code portion to compute reciprocal of loop
invariant denominator in integer division after codegen prepare
expansion.

Differential Revis

[AMDGPU] Enable LICM in the BE pipeline

This allows to hoist code portion to compute reciprocal of loop
invariant denominator in integer division after codegen prepare
expansion.

Differential Revision: https://reviews.llvm.org/D48604

llvm-svn: 335988

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