[PowerPC] Define SchedModel for Power8

PowerPC subtargets prior to Power9 use the 'legacy' itinerary way to
provide scheduling information. This patch re-writes the tablegen file
to define the sched

[PowerPC] Define SchedModel for Power8

PowerPC subtargets prior to Power9 use the 'legacy' itinerary way to
provide scheduling information. This patch re-writes the tablegen file
to define the scheduling information in the new SchedModel way, which
can bring improvements to some benchmarks.

Reviewed By: shchenz

Differential Revision: https://reviews.llvm.org/D154488

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[PowerPC] make expensive mflr be away from its user in the function prologue

mflr is kind of expensive on Power version smaller than 10, so we should
schedule the store for the mflr's def away from

[PowerPC] make expensive mflr be away from its user in the function prologue

mflr is kind of expensive on Power version smaller than 10, so we should
schedule the store for the mflr's def away from mflr.

In epilogue, the expensive mtlr has no user for its def, so it doesn't
matter that the load and the mtlr are back-to-back.

Reviewed By: RolandF

Differential Revision: https://reviews.llvm.org/D137423

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[PPC] Opaque pointer migration, part 1.

The LIT test cases were migrated with the script provided by
Nikita Popov. Due to the size of the change it is split into
several parts.

Reviewed By: nemanja

[PPC] Opaque pointer migration, part 1.

The LIT test cases were migrated with the script provided by
Nikita Popov. Due to the size of the change it is split into
several parts.

Reviewed By: nemanja, amyk, nikic, PowerPC

Differential Revision: https://reviews.llvm.org/D135470

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[PowerPC] Remove support for SplitCSR.

SplitCSR was only suppored for functions with CXX_FAST_TLS calling
convention. Clang only emits that calling convention for Darwin which is
no longer supported

[PowerPC] Remove support for SplitCSR.

SplitCSR was only suppored for functions with CXX_FAST_TLS calling
convention. Clang only emits that calling convention for Darwin which is
no longer supported by the PowerPC backend. Another IR producer could
use the calling convention, but considering the calling convention is
meant to be an optimization and the codegen for SplitCSR can be
attrocious on Power (see the modifed lit test) it is best to remove it
and codegen CXX_FAST_TLS same as the C calling convention.

Differential Revision: https://reviews.llvm.org/D79018

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[PowerPC][NFC] Add more check directives in only cxx_fast_tlscc lit test.

Use utils/update_llc_test_checks.py to add full CHECK directives to the
test for cxx_fast_tls calling convention. The callin

[PowerPC][NFC] Add more check directives in only cxx_fast_tlscc lit test.

Use utils/update_llc_test_checks.py to add full CHECK directives to the
test for cxx_fast_tls calling convention. The calling convention is
arguably dead on PowerPC since dropping Darwin subtarget support in the PowerPC
backend. This test change helps show the atrocious code generation for
this lit test which was hidden by having few CHECK directives.

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Migrate function attribute "no-frame-pointer-elim" to "frame-pointer"="all" as cleanups after D56351

[CodeGen] Always use `printReg` to print registers in both MIR and debug
output

As part of the unification of the debug format and the MIR format,
always use `printReg` to print all kinds of registe

[CodeGen] Always use `printReg` to print registers in both MIR and debug
output

As part of the unification of the debug format and the MIR format,
always use `printReg` to print all kinds of registers.

Updated the tests using '_' instead of '%noreg' until we decide which
one we want to be the default one.

Differential Revision: https://reviews.llvm.org/D40421

llvm-svn: 319445

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Use PIC relocation model as default for PowerPC64 ELF.

Most of the PowerPC64 code generation for the ELF ABI is already PIC.
There are four main exceptions:
(1) Constant pointer arrays etc. should i

Use PIC relocation model as default for PowerPC64 ELF.

Most of the PowerPC64 code generation for the ELF ABI is already PIC.
There are four main exceptions:
(1) Constant pointer arrays etc. should in writeable sections.
(2) The TOC restoration NOP after a call is needed for all global
symbols. While GNU ld has a workaround for questionable GCC self-calls,
we trigger the checks for calls from COMDAT sections as they cross input
sections and are therefore not considered self-calls. The current
decision is questionable and suboptimal, but outside the scope of the
change.
(3) TLS access can not use the initial-exec model.
(4) Jump tables should use relative addresses. Note that the current
encoding doesn't work for the large code model, but it is more compact
than the default for any non-trivial jump table. Improving this is again
beyond the scope of this change.

At least (1) and (3) are assumptions made in target-independent code and
introducing additional hooks is a bit messy. Testing with clang shows
that a -fPIC binary is 600KB smaller than the corresponding -fno-pic
build. Separate testing from improved jump table encodings would explain
only about 100KB or so. The rest is expected to be a result of more
aggressive immediate forming for -fno-pic, where the -fPIC binary just
uses TOC entries.

This change brings the LLVM output in line with the GCC output, other
PPC64 compilers like XLC on AIX are known to produce PIC by default
as well. The relocation model can still be provided explicitly, i.e.
when using MCJIT.

One test case for case (1) is included, other test cases with relocation
mode sensitive behavior are wired to static for now. They will be
reviewed and adjusted separately.

Differential Revision: https://reviews.llvm.org/D26566

llvm-svn: 289743

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Adding -verify-machineinstrs option to PowerPC tests

Currently we have a number of tests that fail with -verify-machineinstrs.
To detect this cases earlier we add the option to the testcases with th

Adding -verify-machineinstrs option to PowerPC tests

Currently we have a number of tests that fail with -verify-machineinstrs.
To detect this cases earlier we add the option to the testcases with the
exception of tests that will currently fail with this option. PR 27456 keeps
track of this failures.

No code review, as discussed with Hal Finkel.

llvm-svn: 277624

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CXX_FAST_TLS calling convention: performance improvement for PPC64

This is the same change on PPC64 as r255821 on AArch64. I have even borrowed
his commit message.

The access function has a short e

CXX_FAST_TLS calling convention: performance improvement for PPC64

This is the same change on PPC64 as r255821 on AArch64. I have even borrowed
his commit message.

The access function has a short entry and a short exit, the initialization
block is only run the first time. To improve the performance, we want to
have a short frame at the entry and exit.

We explicitly handle most of the CSRs via copies. Only the CSRs that are not
handled via copies will be in CSR_SaveList.

Frame lowering and prologue/epilogue insertion will generate a short frame
in the entry and exit according to CSR_SaveList. The majority of the CSRs will
be handled by register allcoator. Register allocator will try to spill and
reload them in the initialization block.

We add CSRsViaCopy, it will be explicitly handled during lowering.

1> we first set FunctionLoweringInfo->SplitCSR if conditions are met (the target
supports it for the given machine function and the function has only return
exits). We also call TLI->initializeSplitCSR to perform initialization.
2> we call TLI->insertCopiesSplitCSR to insert copies from CSRsViaCopy to
virtual registers at beginning of the entry block and copies from virtual
registers to CSRsViaCopy at beginning of the exit blocks.
3> we also need to make sure the explicit copies will not be eliminated.

Author: Tom Jablin (tjablin)
Reviewers: hfinkel kbarton cycheng

http://reviews.llvm.org/D17533

llvm-svn: 265781

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