[RISCV] Enable store clustering by default (#73796)

Builds on #73789, enabling store clustering by default using the same
heuristic.

[RISCV] Move compressible registers to the beginning of the FP allocation order.

We don't have very many compressible FP instructions, just load and store.
These instruction require the FP register

[RISCV] Move compressible registers to the beginning of the FP allocation order.

We don't have very many compressible FP instructions, just load and store.
These instruction require the FP register to be f8-f15.

This patch changes the FP allocation order to prioritize f10-f15 first.
These are also the FP argument registers. So I allocated them in reverse
order starting at f15 to avoid taking the first argument registers.
This appears to match gcc allocation order.

Reviewed By: asb

Differential Revision: https://reviews.llvm.org/D146488

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[RISCV] Enable machine copy propagation for copy-like instructions

Like what has been done in AArch64 (D125335).

We enable this under `-O2` to show the codegen diffs here but we
may only do this un

[RISCV] Enable machine copy propagation for copy-like instructions

Like what has been done in AArch64 (D125335).

We enable this under `-O2` to show the codegen diffs here but we
may only do this under `-O3` like AArch64.

There are two cases that we may produce these eliminable copies:
1. ISel of `FrameIndex`. Like `rvv/fixed-vectors-calling-conv.ll`.
2. Tail duplication. Like `select-optimize-multiple.ll`.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D144535

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[RISCV] Don't use constantpool for floating-point value if the value can be easily constructed by integer sequence and a floating-point move.

In addition, this commit does the following combine

vfm

[RISCV] Don't use constantpool for floating-point value if the value can be easily constructed by integer sequence and a floating-point move.

In addition, this commit does the following combine

vfmv.v.f + fmv.[dhw].x -> vmv.v.x
vfmv.s.f + fmv.[dhw].x -> vmv.s.x
vfmerge.vfm + fmv.[dhw].x -> vmerge.vxm

Differential Revision: https://reviews.llvm.org/D142953

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[RISCV] Add ANDI to getRegAllocationHints.

[RISCV] Use register allocation hints to improve use of compressed instructions.

Compressed instructions usually require one of the source registers
to also be the source register. The register allo

[RISCV] Use register allocation hints to improve use of compressed instructions.

Compressed instructions usually require one of the source registers
to also be the source register. The register allocator doesn't have
that bias on its own.

This patch adds register allocation hints to introduce this bias.
I've started with ADDI, ADDIW, and SLLI. These all have a 5-bit
field for the register. If the source and dest register are the
same they are guaranteed to compress as long as the immediate is
also 6 bits.

This code was inspired by similar code from the SystemZ target.

Reviewed By: reames

Differential Revision: https://reviews.llvm.org/D138242

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[RISCV] Remove support for the unratified Zbt extension.

This extension does not appear to be on its way to ratification.

Out of the unratified bitmanip extensions, this one had the
largest impact

[RISCV] Remove support for the unratified Zbt extension.

This extension does not appear to be on its way to ratification.

Out of the unratified bitmanip extensions, this one had the
largest impact on the compiler.

Posting this patch to start a discussion about whether we should
remove these extensions. We'll talk more at the RISC-V sync meeting this
Thursday.

Reviewed By: asb, reames

Differential Revision: https://reviews.llvm.org/D133834

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[RISCV] Optimize 2x SELECT for floating-point types

Including the following opcode:
Select_FPR16_Using_CC_GPR
Select_FPR32_Using_CC_GPR
Select_FPR64_Using_CC_GPR

Reviewed By: craig.topper

Diffe

[RISCV] Optimize 2x SELECT for floating-point types

Including the following opcode:
Select_FPR16_Using_CC_GPR
Select_FPR32_Using_CC_GPR
Select_FPR64_Using_CC_GPR

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D127871

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Revert "[RISCV] Optimize 2x SELECT for floating-point types"

This reverts commit 1178992c72b002c3b2c87203252c566eeb273cc1.

[RISCV] Optimize 2x SELECT for floating-point types

Including the following opcode:
Select_FPR16_Using_CC_GPR
Select_FPR32_Using_CC_GPR
Select_FPR64_Using_CC_GPR

Reviewed By: craig.topper

Diffe

[RISCV] Optimize 2x SELECT for floating-point types

Including the following opcode:
Select_FPR16_Using_CC_GPR
Select_FPR32_Using_CC_GPR
Select_FPR64_Using_CC_GPR

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D127871

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[RISCV] Update computeTargetABI from llc as well as clang

Clang computes the default ABI if -mabi is empty
and encode it in LLVM IR module flag since D105555.
For correctness, llc need to give the s

[RISCV] Update computeTargetABI from llc as well as clang

Clang computes the default ABI if -mabi is empty
and encode it in LLVM IR module flag since D105555.
For correctness, llc need to give the same target-abi
(Options.MCOptions.ABIName) with ABI encoded in IR.
The getSubtargetImpl already has a check for them only if
Options.MCOptions.ABIName is not empty.

In order to get more robustness we could have a check for
explicit ABI, but now we have two different logic to
compute the default ABI.

The front-end ABI is defautl to the ilp32/ilp32e/lp64, and
ilp32d/lp64d when hardware support for extension D.
The backend ABI is default to the ilp32/ilp32e/lp64.

Reviewed by: asb, jrtc27

Differential Revision: https://reviews.llvm.org/D118333

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[RISCV] Set CostPerUse to 1 iff RVC is enabled

After D86836, we can define multiple cost values for
different cost models. So here we set CostPerUse to
1 iff RVC is enabled to avoid potential impact

[RISCV] Set CostPerUse to 1 iff RVC is enabled

After D86836, we can define multiple cost values for
different cost models. So here we set CostPerUse to
1 iff RVC is enabled to avoid potential impact on RA.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D117741

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[RISCV] Generate pseudo instruction li

Add an alias of `addi [x], zero, imm` to generate pseudo
instruction li, which makes assembly mush more readable.
For existed tests, users can update them by r

[RISCV] Generate pseudo instruction li

Add an alias of `addi [x], zero, imm` to generate pseudo
instruction li, which makes assembly mush more readable.
For existed tests, users can update them by running script
`llvm/utils/update_llc_test_checks.py`.

Reviewed By: asb

Differential Revision: https://reviews.llvm.org/D112692

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[RISCV] Add more cmov isel patterns to handle seteq/ne with a small non-zero immediate.

Similar to our free standing setcc patterns, we can use ADDI to
subtract the immediate from the other operand.

[RISCV] Add more cmov isel patterns to handle seteq/ne with a small non-zero immediate.

Similar to our free standing setcc patterns, we can use ADDI to
subtract the immediate from the other operand. Then the cmov
can check if the result is zero or non-zero.

Reviewed By: mundaym

Differential Revision: https://reviews.llvm.org/D95169

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Recommit "[RISCV] Legalize select when Zbt extension available"

This recommits 71ed4b6ce57d8843ef705af8f98305976a8f107a with
the polarity of some of the pattern corrected.

Original commit message:

Recommit "[RISCV] Legalize select when Zbt extension available"

This recommits 71ed4b6ce57d8843ef705af8f98305976a8f107a with
the polarity of some of the pattern corrected.

Original commit message:
The custom expansion of select operations in the RISC-V backend
interferes with the matching of cmov instructions. Legalizing
select when the Zbt extension is available solves that problem.

Reviewed By: luismarques, craig.topper

Differential Revision: https://reviews.llvm.org/D93767

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[RISCV][NFC] Increase test coverage of Zbt extension

Add Zbt (ternary) extension code generation to the select lowering
tests since it can have a significant impact on how select is
lowered.

While

[RISCV][NFC] Increase test coverage of Zbt extension

Add Zbt (ternary) extension code generation to the select lowering
tests since it can have a significant impact on how select is
lowered.

While we are here make the neg-abs commands more consistent with
the other tests.

Reviewed By: lenary

Differential Revision: https://reviews.llvm.org/D94798

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[RISCV] Add MemOperand to the instruction created by storeRegToStackSlot/loadRegFromStackSlot

Differential Revision: https://reviews.llvm.org/D91730

[MachineSink] sink more profitable loads

Reviewed By: qcolombet

Differential Revision: https://reviews.llvm.org/D86864

[RISCV] Switch to the Machine Scheduler

Most of the test changes are trivial instruction reorderings and differing
register allocations, without any obvious performance impact.

Differential Revisio

[RISCV] Switch to the Machine Scheduler

Most of the test changes are trivial instruction reorderings and differing
register allocations, without any obvious performance impact.

Differential Revision: https://reviews.llvm.org/D66973

llvm-svn: 372106

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Revert Patch from Phabricator

This reverts r372092 (git commit e38695a0255c9e7b53639f349f8101bae1ce5c04)

llvm-svn: 372104

Patch from Phabricator

llvm-svn: 372092

[RISCV] Custom legalize i32 operations for RV64 to reduce signed extensions

Differential Revision: https://reviews.llvm.org/D65434

llvm-svn: 367960

[RISCV] Optimize emission of SELECT sequences

This patch optimizes the emission of a sequence of SELECTs with the same
condition, avoiding the insertion of unnecessary control flow. Such a sequence

[RISCV] Optimize emission of SELECT sequences

This patch optimizes the emission of a sequence of SELECTs with the same
condition, avoiding the insertion of unnecessary control flow. Such a sequence
often occurs when a SELECT of values wider than XLEN is legalized into two
SELECTs with legal types. We have identified several use cases where the
SELECTs could be interleaved with other instructions. Therefore, we extend the
sequence to include non-SELECT instructions if we are able to detect that the
non-SELECT instructions do not impact the optimization.

This patch supersedes https://reviews.llvm.org/D59096, which attempted to
address this issue by introducing a new SelectionDAG node. Hat tip to Eli
Friedman for his feedback on how to best handle this issue.

Differential Revision: https://reviews.llvm.org/D59355
Patch by Luís Marques.

llvm-svn: 356741

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