[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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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] Split vgpr regalloc pipeline (#93526)

Allocating wwm-registers and per-thread VGPR operands
together imposes many challenges in the way the
registers are reused during allocation. There a

[AMDGPU] Split vgpr regalloc pipeline (#93526)

Allocating wwm-registers and per-thread VGPR operands
together imposes many challenges in the way the
registers are reused during allocation. There are
times when regalloc reuses the registers of regular
VGPRs operations for wwm-operations in a small range
leading to unwantedly clobbering their inactive lanes
causing correctness issues that are hard to trace.

This patch splits the VGPR allocation pipeline further
to allocate wwm-registers first and the regular VGPR
operands in a separate pipeline. The splitting would
ensure that the physical registers used for wwm
allocations won't take part in the next allocation
pipeline to avoid any such clobbering.

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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] Use glue for convergence tokens at call-like operations (#86766)

The earlier implementation on AMDGPU used explicit token operands at
SI_CALL and SI_CALL_ISEL. This is now replaced with CO

[AMDGPU] Use glue for convergence tokens at call-like operations (#86766)

The earlier implementation on AMDGPU used explicit token operands at
SI_CALL and SI_CALL_ISEL. This is now replaced with CONVERGENCECTRL_GLUE
operands, with the following effects:

- The treatment of tokens at call-like operations is now consistent with
the treatment at intrinsics.
- Support for tail calls using implicit tokens at SI_TCRETURN "just
works".
- The extra parameter at call-like instructions is eliminated, thus
restoring those instructions and their handling to the original state.

The new glue node is placed after the existing glue node for the
outgoing call parameters, which seems to not interfere with selection of
the call-like nodes.

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[AMDGPU] Rename COV module flag to amdhsa_code_object_version (#79905)

The previous name 'amdgpu_code_object_version', was misleading since
this is really a property of the HSA OS. The new spelling

[AMDGPU] Rename COV module flag to amdhsa_code_object_version (#79905)

The previous name 'amdgpu_code_object_version', was misleading since
this is really a property of the HSA OS. The new spelling also matches
the asm directive I added in bc82cfb.

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Restore "Implement convergence control in MIR using SelectionDAG (#71785)"

This restores commit c7fdd8c11e54585dc9d15d63de9742067e0506b9.
Previously reverted in f010b1bef4dda2c7082cbb41dbabf1f149cce

Restore "Implement convergence control in MIR using SelectionDAG (#71785)"

This restores commit c7fdd8c11e54585dc9d15d63de9742067e0506b9.
Previously reverted in f010b1bef4dda2c7082cbb41dbabf1f149cce306.

LLVM function calls carry convergence control tokens as operand bundles, where
the tokens themselves are produced by convergence control intrinsics. This patch
implements convergence control tokens in MIR as follows:

1. Introduce target-independent ISD opcodes and MIR opcodes for convergence
control intrinsics.
2. Model token values as untyped virtual registers in MIR.

The change also introduces an additional ISD opcode CONVERGENCECTRL_GLUE and a
corresponding machine opcode with the same spelling. This glues the convergence
control token to SDNodes that represent calls to intrinsics. The glued token is
later translated to an implicit argument in the MIR.

The lowering of calls to user-defined functions is target-specific. On AMDGPU,
the convergence control operand bundle at a non-intrinsic call is translated to
an explicit argument to the SI_CALL_ISEL instruction. Post-selection adjustment
converts this explicit argument to an implicit argument on the SI_CALL
instruction.

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Revert "Restore "Implement convergence control in MIR using SelectionDAG (#71785)""

This reverts commit c7fdd8c11e54585dc9d15d63de9742067e0506b9.

Reason: Broke the sanitizer buildbots. See the comm

Revert "Restore "Implement convergence control in MIR using SelectionDAG (#71785)""

This reverts commit c7fdd8c11e54585dc9d15d63de9742067e0506b9.

Reason: Broke the sanitizer buildbots. See the comments at
https://github.com/llvm/llvm-project/pull/71785
for more information.

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Restore "Implement convergence control in MIR using SelectionDAG (#71785)"

Original commit 79889734b940356ab3381423c93ae06f22e772c9.
Perviously reverted in commit a2afcd5721869d1d03c8146bae3885b3385

Restore "Implement convergence control in MIR using SelectionDAG (#71785)"

Original commit 79889734b940356ab3381423c93ae06f22e772c9.
Perviously reverted in commit a2afcd5721869d1d03c8146bae3885b3385ba15e.

LLVM function calls carry convergence control tokens as operand bundles, where
the tokens themselves are produced by convergence control intrinsics. This patch
implements convergence control tokens in MIR as follows:

1. Introduce target-independent ISD opcodes and MIR opcodes for convergence
control intrinsics.
2. Model token values as untyped virtual registers in MIR.

The change also introduces an additional ISD opcode CONVERGENCECTRL_GLUE and a
corresponding machine opcode with the same spelling. This glues the convergence
control token to SDNodes that represent calls to intrinsics. The glued token is
later translated to an implicit argument in the MIR.

The lowering of calls to user-defined functions is target-specific. On AMDGPU,
the convergence control operand bundle at a non-intrinsic call is translated to
an explicit argument to the SI_CALL_ISEL instruction. Post-selection adjustment
converts this explicit argument to an implicit argument on the SI_CALL
instruction.

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Revert "Implement convergence control in MIR using SelectionDAG (#71785)"

This reverts commit 79889734b940356ab3381423c93ae06f22e772c9.

Encountered multiple buildbot failures.

Implement convergence control in MIR using SelectionDAG (#71785)

LLVM function calls carry convergence control tokens as operand bundles, where
the tokens themselves are produced by convergence con

Implement convergence control in MIR using SelectionDAG (#71785)

LLVM function calls carry convergence control tokens as operand bundles, where
the tokens themselves are produced by convergence control intrinsics. This patch
implements convergence control tokens in MIR as follows:

1. Introduce target-independent ISD opcodes and MIR opcodes for convergence
control intrinsics.
2. Model token values as untyped virtual registers in MIR.

The change also introduces an additional ISD opcode CONVERGENCECTRL_GLUE and a
corresponding machine opcode with the same spelling. This glues the convergence
control token to SDNodes that represent calls to intrinsics. The glued token is
later translated to an implicit argument in the MIR.

The lowering of calls to user-defined functions is target-specific. On AMDGPU,
the convergence control operand bundle at a non-intrinsic call is translated to
an explicit argument to the SI_CALL_ISEL instruction. Post-selection adjustment
converts this explicit argument to an implicit argument on the SI_CALL
instruction.

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[AMDGPU] Don't fix the scavenge slot at offset 0 (#79136)

At the moment, the emergency spill slot is a fixed object for entry
functions and chain functions, and a regular stack object otherwise.
T

[AMDGPU] Don't fix the scavenge slot at offset 0 (#79136)

At the moment, the emergency spill slot is a fixed object for entry
functions and chain functions, and a regular stack object otherwise.
This patch adopts the latter behaviour for entry/chain functions too. It
seems this was always the intention [1] and it will also save us a bit
of stack space in cases where the first stack object has a large
alignment.

[1]
https://github.com/llvm/llvm-project/commit/34c8b835b16fb3879f1b9770e91df21883356bb6

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[AMDGPU] Pick available high VGPR for CSR SGPR spilling (#78669)

CSR SGPR spilling currently uses the early available physical VGPRs. It
currently imposes a high register pressure while trying to a

[AMDGPU] Pick available high VGPR for CSR SGPR spilling (#78669)

CSR SGPR spilling currently uses the early available physical VGPRs. It
currently imposes a high register pressure while trying to allocate
large VGPR tuples within the default register budget.

This patch changes the spilling strategy by picking the VGPRs in the
reverse order, the highest available VGPR first and later after regalloc
shift them back to the lowest available range. With that, the initial
VGPRs would be available for allocation and possibility
of finding large number of contiguous registers will be more.

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[AMDGPU][NFC] Check more autogenerated llc tests for COV5 (#75219)

Regenerate a few more llc tests to check for COV5 instead of the default
ABI version.

[AMDGPU] Add option to pre-allocate SGPR spill VGPRs (#70626)

SGPR spill VGPRs are WWM registers so allow them to be allocated by
SIPreAllocateWWMRegs pass.
This intentionally prevents spilling of

[AMDGPU] Add option to pre-allocate SGPR spill VGPRs (#70626)

SGPR spill VGPRs are WWM registers so allow them to be allocated by
SIPreAllocateWWMRegs pass.
This intentionally prevents spilling of these VGPRs when enabled.

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[AMDGPU] Use absolute relocations when compiling for AMDPAL and Mesa3D (#67791)

The primary ISA-independent justification for using PC-relative
addressing is that it makes code position-independent

[AMDGPU] Use absolute relocations when compiling for AMDPAL and Mesa3D (#67791)

The primary ISA-independent justification for using PC-relative
addressing is that it makes code position-independent and therefore
allows sharing of .text pages between processes.

When not sharing .text pages, we can use absolute relocations instead,
which will possibly prevent a bubble introduced by s_getpc_b64.

Co-authored-by: Thomas Symalla <thomas.symalla@amd.com>

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Revert "[AMDGPU] Make default AMDHSA Code Object Version to be 5 (#65410)" (#66060)

This reverts commit 0a8d17e79b02a92814a2a788d79df1f54d70ec3e.

[AMDGPU] Make default AMDHSA Code Object Version to be 5 (#65410)

Also update LIT tests and docs.
For more details, see
https://llvm.org/docs/AMDGPUUsage.html#code-object-v5-metadata

Reviewed B

[AMDGPU] Make default AMDHSA Code Object Version to be 5 (#65410)

Also update LIT tests and docs.
For more details, see
https://llvm.org/docs/AMDGPUUsage.html#code-object-v5-metadata

Reviewed By: arsenm, jhuber6

Github PR: #65410

Differential Revision: https://reviews.llvm.org/D129818

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AMDGPU: Handle llvm.stacksave and llvm.stackrestore

Not sure if the only valid use is to have stackrestore directly
consume stacksave outputs or not. Handled exactly like a regular stack
pointer so

AMDGPU: Handle llvm.stacksave and llvm.stackrestore

Not sure if the only valid use is to have stackrestore directly
consume stacksave outputs or not. Handled exactly like a regular stack
pointer so all the edge cases theoretically should work.

https://reviews.llvm.org/D156669

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