[AMDGPU] Restore SP from saved-FP or saved-BP (#124007)

Currently, the AMDGPU backend bumps the Stack Pointer
by fixed size offsets in the prolog of device functions, and
restores it by the same

[AMDGPU] Restore SP from saved-FP or saved-BP (#124007)

Currently, the AMDGPU backend bumps the Stack Pointer
by fixed size offsets in the prolog of device functions, and
restores it by the same amount in the epilog.
Prolog:
sp += frameSize

Epilog:
sp -= frameSize

If a function has dynamic stack realignment,
Prolog:
sp += frameSize + max_alignment

Epilog:
sp -= frameSize + max_alignment

These calculations are not optimal in case of dynamic
stack realignment, and completely fail in case of
dynamic stack readjustment.
This patch uses the saved Frame Pointer to restore SP.
Prolog:
fp = sp
sp += frameSize

Epilog:
sp = fp

In case of dynamic stack realignment, SP is restored from
the saved Base Pointer.
Prolog:
fp = sp + (max_alignment - 1)
fp = fp & (-max_alignment)
bp = sp
sp += frameSize + max_alignment

Epilog:
sp = bp

(Note: The presence of BP has been enforced in case of any
dynamic stack realignment.)

---------

Co-authored-by: Pravin Jagtap <Pravin.Jagtap@amd.com>
Co-authored-by: Matt Arsenault <arsenm2@gmail.com>

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AMDGPU: Fix using illegal VOP3 literal in frame index elimination (#115747)

AMDGPU: Default to selecting frame indexes to SGPRs (#115060)

Only select to a VGPR if it's trivally used in VGPR only contexts.
This fixes mishandling frame indexes used in SGPR only contexts,
like

AMDGPU: Default to selecting frame indexes to SGPRs (#115060)

Only select to a VGPR if it's trivally used in VGPR only contexts.
This fixes mishandling frame indexes used in SGPR only contexts,
like inline assembly constraints.

This is suboptimal in the common case where the frame index
is transitively used by only VALU ops. We make up for this by later
folding the copy to VALU plus scalar op in SIFoldOperands.

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Reapply "[AMDGPU] Still set up the two SGPRs for queue ptr even it is COV5 (#112403)"

This reverts commit ca33649abe5fad93c57afef54e43ed9b3249cd86.

Revert "[AMDGPU] Still set up the two SGPRs for queue ptr even it is COV5 (#112403)"

This reverts commit e215a1e27d84adad2635a52393621eb4fa439dc9 as it broke both
hip and openmp buildbots.

[AMDGPU] Still set up the two SGPRs for queue ptr even it is COV5 (#112403)

AMDGPU: Try to reuse dest reg for s_add_i32 frame indexes (#111201)

Hack around the register scavenger doing the wrong thing.
It does not find the result register as available in the
case the fram

AMDGPU: Try to reuse dest reg for s_add_i32 frame indexes (#111201)

Hack around the register scavenger doing the wrong thing.
It does not find the result register as available in the
case the frame index add isn't also reading the dest register.
This is the quick fix for a regression where the scavenge would
create a broken spill of SGPR to memory. I believe this is still
broken for cases we cannot use the result register.

I'm confused about what position the scavenger iterator
is supposed to be in, and what RestoreAfter is for. The scavenger
is missing a full set of forward/backward APIs and there seems
to be an off by one somewhere.

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AMDGPU: Handle folding frame indexes into s_add_i32 (#101694)

This does not yet enable producing direct frame index
references in s_add_i32, only the lowering.

Reapply "AMDGPU: Move attributor into optimization pipeline (#83131)" and follow up commit "clang/AMDGPU: Defeat attribute optimization in attribute test" (#98851)

This reverts commit adaff46d087799

Reapply "AMDGPU: Move attributor into optimization pipeline (#83131)" and follow up commit "clang/AMDGPU: Defeat attribute optimization in attribute test" (#98851)

This reverts commit adaff46d087799072438dd744b038e6fd50a2d78.

Drop the -O3 checks from default-attributes.hip. I don't know why they
are different on some bots but reverting this is far too disruptive.

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Revert "AMDGPU: Move attributor into optimization pipeline (#83131)" and follow up commit "clang/AMDGPU: Defeat attribute optimization in attribute test" (#98851)

This reverts commits 677cc15e0ff2e0

Revert "AMDGPU: Move attributor into optimization pipeline (#83131)" and follow up commit "clang/AMDGPU: Defeat attribute optimization in attribute test" (#98851)

This reverts commits 677cc15e0ff2e0e6aa30538eb187990a6a8f53c0 and
78bc1b64a6dc3fb6191355a5e1b502be8b3668e7.

The test CodeGenHIP/default-attributes.hip is failing on multiple bots
even after the attempted fix including the following:
- https://lab.llvm.org/buildbot/#/builders/3/builds/1473
- https://lab.llvm.org/buildbot/#/builders/65/builds/1380
- https://lab.llvm.org/buildbot/#/builders/161/builds/595
- https://lab.llvm.org/buildbot/#/builders/154/builds/1372
- https://lab.llvm.org/buildbot/#/builders/133/builds/1547
- https://lab.llvm.org/buildbot/#/builders/81/builds/755
- https://lab.llvm.org/buildbot/#/builders/40/builds/570
- https://lab.llvm.org/buildbot/#/builders/13/builds/748
- https://lab.llvm.org/buildbot/#/builders/12/builds/1845
- https://lab.llvm.org/buildbot/#/builders/11/builds/1695
- https://lab.llvm.org/buildbot/#/builders/190/builds/1829
- https://lab.llvm.org/buildbot/#/builders/193/builds/962
- https://lab.llvm.org/buildbot/#/builders/23/builds/991
- https://lab.llvm.org/buildbot/#/builders/144/builds/2256
- https://lab.llvm.org/buildbot/#/builders/46/builds/1614

These bots have been broken for a day, so reverting to get everything
back to green.

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AMDGPU: Move attributor into optimization pipeline (#83131)

Removing it from the codegen pipeline induces a lot of test churn
because llc is no longer optimizing out implicit arguments to kernels.

AMDGPU: Move attributor into optimization pipeline (#83131)

Removing it from the codegen pipeline induces a lot of test churn
because llc is no longer optimizing out implicit arguments to kernels.

Mostly mechanical, but there are some creative test updates. I preferred
to take the changes as-is in tests where the ABI isn't relevant. In
cases where it's more relevant, or the optimize out logic was too
ingrained in the test, I pre-run the optimization. Some cases manually
add attributes to disable inputs.

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[AMDGPU] Switch to backwards scavenging in eliminateFrameIndex

Frame index elimination runs backwards so we must use backwards
scavenging. Otherwise, when a scavenged register is spilled, the
scaven

[AMDGPU] Switch to backwards scavenging in eliminateFrameIndex

Frame index elimination runs backwards so we must use backwards
scavenging. Otherwise, when a scavenged register is spilled, the
scavenger will remember that the register is in use until the restore
point, but it will never reach that restore point. The result is that in
some cases it will keep scavenging different registers instead of
reusing the same one.

Differential Revision: https://reviews.llvm.org/D152394

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[RegScavenger] Change scavengeRegister to pick registers in allocation order

This matches what scavengeRegisterBackwards does.

This is in preparation for converting most uses of scavengeRegister to

[RegScavenger] Change scavengeRegister to pick registers in allocation order

This matches what scavengeRegisterBackwards does.

This is in preparation for converting most uses of scavengeRegister to
scavengeRegisterBackwards, to reduce test case churn when that lands and
to help with bisection if anything goes wrong.

Differential Revision: https://reviews.llvm.org/D150792

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[AMDGPU] Convert some tests to opaque pointers (NFC)

PEI should be able to use backward walk in replaceFrameIndicesBackward.

The backward register scavenger has correct register
liveness information. PEI should leverage the backward register scavenger

PEI should be able to use backward walk in replaceFrameIndicesBackward.

The backward register scavenger has correct register
liveness information. PEI should leverage the backward register scavenger.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D137574

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[Sink] Process basic blocks with a single successor

This condition seems unnecessary.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D93511

Revert D137574 "PEI should be able to use backward walk in replaceFrameIndicesBackward."

This reverts commit e05ce03cfa0b36e9b99149e21afcb1fc039df813.

Caused asan use-after-poison to 4 DebugInfo/AM

Revert D137574 "PEI should be able to use backward walk in replaceFrameIndicesBackward."

This reverts commit e05ce03cfa0b36e9b99149e21afcb1fc039df813.

Caused asan use-after-poison to 4 DebugInfo/AMDGPU/ tests.
Triggered in PEI::replaceFrameIndicesBackward called llvm::MachineInstr::getNumOperands

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PEI should be able to use backward walk in replaceFrameIndicesBackward.

The backward register scavenger has correct register
liveness information. PEI should leverage the backward register scavenger

PEI should be able to use backward walk in replaceFrameIndicesBackward.

The backward register scavenger has correct register
liveness information. PEI should leverage the backward register scavenger.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D137574

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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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PrologEpilogInserter: Use explicit control for scavenge slot placement

AMDGPU is unusual in that the both stack is indexed in the same
direction as stack growth (up). We therefore always need the em

PrologEpilogInserter: Use explicit control for scavenge slot placement

AMDGPU is unusual in that the both stack is indexed in the same
direction as stack growth (up). We therefore always need the emergency
stack slots placed as low as possible to ensure they are in range of
load/store instruction immediate offsets. The existing logic is mostly
OK, but failed if we required stack realignment.

I don't understand what the existing control isFPCloseToIncomingSP is
supposed to mean, but can only be used to stop placing the scavenge
slots earlier. Make this explicit so that targets can opt-in rather
than opt-out only.

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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] 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] Use s_add_i32 for address additions

This allows to convert the add instruction to s_addk_i32 and
v_add_nc_u32 instead of needing v_add_co_u32 when converting to a VALU
instruction.

Differe

[AMDGPU] Use s_add_i32 for address additions

This allows to convert the add instruction to s_addk_i32 and
v_add_nc_u32 instead of needing v_add_co_u32 when converting to a VALU
instruction.

Differential Revision: https://reviews.llvm.org/D103322

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[AMDGPU] Restrict immediate scratch offsets

gfx9 does not work with negative offsets, gfx10 works only with
aligned negative offsets, but not with unaligned negative offsets.

This is slightly more

[AMDGPU] Restrict immediate scratch offsets

gfx9 does not work with negative offsets, gfx10 works only with
aligned negative offsets, but not with unaligned negative offsets.

This is slightly more conservative than needed, gfx9 does support
negative offsets when a VGPR address is used and gfx10 supports
negative, unaligned offsets when an SGPR address is used, but we
do not make use of that with this patch.

Differential Revision: https://reviews.llvm.org/D101292

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