Commit Graph

61 Commits

Author SHA1 Message Date
Craig Topper e2bfbed2bb [RISCV] Add ReadFStoreData as a SchedRead.
The floating point stores use a different register class, it
probably makes sense to have a different SchedRead.

Reviewed By: monkchiang

Differential Revision: https://reviews.llvm.org/D131379
2022-08-08 09:33:19 -07:00
Craig Topper 450edb0b37 [RISCV] Explicitly select second operand of branch condition to X0.
At least based on the lit tests, the coalescer sometimes fails to
propagate the copy from X0 into the branch instruction. This patch
does it manually during isel. The majority of the changes are from
the select patterns.

Some of the changes are just register allocation changes. Only
the Select change affects the whether a b*z instruction is generated
in the tests. I changed the branch pattern for consistency.

Reviewed By: asb

Differential Revision: https://reviews.llvm.org/D130809
2022-08-01 11:16:48 -07:00
LiaoChunyu f14d18c7a9 [RISCV] Add more patterns for FNMADD
D54205 handles fnmadd: -rs1 * rs2 - rs3
This patch add fnmadd: -(rs1 * rs2 + rs3) (the nsz flag on the FMA)

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D126852
2022-06-04 12:31:45 +08:00
Craig Topper 72a66358f6 [RISCV] Add isCommutable to FADD/FMUL/FMIN/FMAX/FEQ.
Reviewed By: arcbbb

Differential Revision: https://reviews.llvm.org/D123972
2022-05-02 20:21:16 -07:00
Craig Topper c2614b31d9 [RISCV] Add isCommutable to scalar FMA instructions.
The default implementation of findCommutedOpIndices picks the
first two source operands. That's exactly what we want for the
scalar FMA instructions.

Reviewed By: reames

Differential Revision: https://reviews.llvm.org/D124463
2022-04-27 11:07:18 -07:00
Shao-Ce SUN 365c858a5d [RISCV] Share PatFprFpr classes for F, D, and Zfh
Inspired by D115469

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D121066
2022-03-08 13:02:04 +08:00
Shao-Ce SUN 0e38b29543 [RISCV] add the MC layer support of Zfinx extension
This patch added the MC layer support of Zfinx extension.

Authored-by: StephenFan
Co-Authored-by: Shao-Ce Sun

Reviewed By: asb

Differential Revision: https://reviews.llvm.org/D93298
2022-03-02 14:25:19 +08:00
Nikita Popov c7fe6f9c92 Revert "[RISCV] add the MC layer support of Zfinx extension"
This reverts commit 7798ecca9c.

As reported in https://reviews.llvm.org/D93298#3331641 and
following, this causes assertion failures with inline assembly.
2022-02-24 12:14:31 +01:00
Shao-Ce SUN 7798ecca9c [RISCV] add the MC layer support of Zfinx extension
This patch added the MC layer support of Zfinx extension.

Authored-by: StephenFan
Co-Authored-by: Shao-Ce Sun

Reviewed By: asb

Differential Revision: https://reviews.llvm.org/D93298
2022-02-17 21:54:13 +08:00
Fraser Cormack 5a12024b95 [RISCV] Optimize lowering of floating-point -0.0
This idea has come up in several reviews -- D115978 and D105902 -- so I
can't take any credit for the idea. Instead of using a constant pool to
lower -0.0, we can emit a sequence of two instructions:

    fmv.[hwd].x freg, zero
    fsgnjn.[hsd] freg, freg, freg

This is only done when the floating-point type is legal.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D117687
2022-01-20 11:46:28 +00:00
Craig Topper 63b17eb9ec [RISCV] Add strictfp support for compares.
This adds support for STRICT_FSETCC(quiet) and STRICT_FSETCCS(signaling).

FEQ matches well to STRICT_FSETCC oeq.
FLT/FLE matches well to STRICT_FSETCCS olt/ole.

Others require commuting operands or multiple instructions.

STRICT_FSETCC olt/ole/ogt/oge/ult/ule/ugt/uge uses FLT/FLE,
but we need to save/restore FFLAGS around them to avoid spurious
exceptions. I've implemented pseudo instructions with a
CustomInserter to insert the save/restore CSR instructions.
Unfortunately, this doesn't honor exceptions for signaling NANs
but I'm not sure if signaling nans are really supported by the
constrained intrinsics.

STRICT_FSETCC one and ueq expand to a pair of FLT instructions
with a save/restore of fflags around each. This could be improved
in the future.

There may be some opportunities to generate better code for strict
comparisons mixed with nonans fast math flags. I've left FIXMEs in
the .td files for that.

Co-Authored-by: ShihPo Hung <shihpo.hung@sifive.com>

Reviewed By: arcbbb

Differential Revision: https://reviews.llvm.org/D116694
2022-01-11 20:01:41 -08:00
Craig Topper 808c662665 [RISCV] Change RISCVISD::FCVT*RTZ opcodes to take rounding mode as an operand.
Pre-work for a future change that will use these opcodes with other
rounding modes.

Differential Revision: https://reviews.llvm.org/D116724
2022-01-06 08:12:12 -08:00
Craig Topper 15787ccd45 [RISCV] Add support for STRICT_LRINT/LLRINT/LROUND/LLROUND. Tests for other strict intrinsics.
This patch adds isel support for STRICT_LRINT/LLRINT/LROUND/LLROUND.

It also adds test cases for f32 and f64 constrained intrinsics that
correspond to the intrinsics in float-intrinsics.ll and
double-intrinsics.ll. Support for promoting the integer argument of
STRICT_FPOWI was added.

I've skipped adding tests for f16 intrinsics, since we don't have libcalls
for them and we have inconsistent support for promoting them in LegalizeDAG.
This will need to be examined more closely.

Reviewed By: asb

Differential Revision: https://reviews.llvm.org/D116323
2021-12-30 11:54:32 -08:00
Shao-Ce SUN 70a98008ea [RISCV] Reduce repetitive codes in flw, fsw
Trying to improve code reuse in F,D,Zfh *.td files.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D116089
2021-12-27 09:29:35 +08:00
Craig Topper b7b260e19a [RISCV] Support strict FP conversion operations.
This adds support for strict conversions between fp types and between
integer and fp.

NOTE: RISCV has static rounding mode instructions, but the constrainted
intrinsic metadata is not used to select static rounding modes. Dynamic
rounding mode is always used.

Differential Revision: https://reviews.llvm.org/D115997
2021-12-23 09:40:58 -06:00
Craig Topper 3926893439 [RISCV] Add isel support for scalar STRICT_FADD/FSUB/FMUL/FDIV/FSQRT.
Test that STRICT_FMINNUM/FMAXNUM are lowered to libcalls for f32/f64.
The RISC-V instructions don't match the behavior of fmin/fmax libcalls
with respect to SNaN.

Promoting FMINNUM/FMAXNUM for f16 needs more work outside of the
RISC-V backend.

Reviewed By: asb, arcbbb

Differential Revision: https://reviews.llvm.org/D115680
2021-12-14 10:50:55 -08:00
Craig Topper 3f1c403a2b [RISCV] Use AdjustInstrPostInstrSelection to insert a FRM dependency for scalar FP instructions with dynamic rounding mode.
In order to support constrained FP intrinsics we need to model FRM
dependency. Whether or not a instruction uses FRM is based on a 3
bit field in the instruction. Because of this we can't add
'Uses = [FRM]' to the tablegen descriptions.

This patch examines the immediate after isel and adds an implicit
use of FRM. This idea came from Roger Ferrer Ibanez.

Other ideas:
We could be overly conservative and just pretend all instructions with
frm field read the FRM register. Or we could have pseudoinstructions
for CodeGen with rounding mode.

Reviewed By: asb, frasercrmck, arcbbb

Differential Revision: https://reviews.llvm.org/D115555
2021-12-14 10:17:57 -08:00
Craig Topper d4d76409d1 [RISCV] Add mayRaiseFPException to RISCV scalar FP instructions.
FRM dependency will be added in a future patch.

Reviewed By: arcbbb

Differential Revision: https://reviews.llvm.org/D115540
2021-12-14 09:53:30 -08:00
Craig Topper 3cda38796c [RISCV] Add rs2 encoding to the FPUnaryOp_r and FPUnaryOp_r_frm template arguments.
Instead of having unary instruction include a 'let' in their class
body, add rs2val as a template parameter. Then we can use a let
in FPUnaryOp_r and FPUnaryOp_r_frm. This reduces the overall
verbosity of the FP files.

Reviewed By: achieveartificialintelligence

Differential Revision: https://reviews.llvm.org/D115537
2021-12-13 21:38:42 -08:00
Craig Topper 80ed2f6b36 [RISCV] Share tablegen classes for F, D, and Zfh. Other simplifications. NFC
By adding the register class and funct as template parameters we
can share the classes with all 3 extensions.

I've used "let SchedRW =" to avoid repeating scheduler classes on
multiple lines where we previously inherited from the Sched class.

A subsequent patch will add mayRaiseFPException and FRM dependencies.
Reducing the number of classes means less repeating for those changes.

This of course conflicts with the Zfinx patch D93298.

Reviewed By: achieveartificialintelligence

Differential Revision: https://reviews.llvm.org/D115469
2021-12-10 09:35:51 -08:00
Craig Topper d4ee84ceee [RISCV] Support FP_TO_S/UINT_SAT for i32 and i64.
The fcvt fp to integer instructions saturate if their input is
infinity or out of range, but the instructions produce a maximum
integer for nan instead of 0 required for the ISD opcodes.

This means we can use the instructions to do the saturating
conversion, but we'll need to fix up the nan case at the end.

We can probably improve the i8 and i16 default codegen as well,
but I'll leave that for a follow up.

Reviewed By: luismarques

Differential Revision: https://reviews.llvm.org/D107230
2021-08-07 16:06:00 -07:00
Craig Topper 593059b328 [RISCV] Rename RISCVISD::FCVT_W_RV64 to FCVT_W_RTZ_RV64. NFC
fcvt.w(u) supports multiple rounding modes, but the ISD node
doesn't encode that. So name it to match the rounding mode it uses.
2021-07-31 11:14:59 -07:00
Craig Topper c63dbd8501 [RISCV] Custom lower (i32 (fptoui/fptosi X)).
I stumbled onto a case where our (sext_inreg (assertzexti32 (fptoui X)), i32)
isel pattern can cause an fcvt.wu and fcvt.lu to be emitted if
the assertzexti32 has an additional user. If we add a one use check
it would just cause a fcvt.lu followed by a sext.w when only need
a fcvt.wu to satisfy both users.

To mitigate this I've added custom isel and new ISD opcodes for
fcvt.wu. This allows us to keep know it started life as a conversion
to i32 without needing to match multiple nodes. ComputeNumSignBits
has been taught that this new nodes produces 33 sign bits. To
prevent regressions when we need to zero extend the result of an
(i32 (fptoui X)), I've added a DAG combine to convert it to an
(i64 (fptoui X)) before type legalization. In most cases this would
happen in InstCombine, but a zero_extend can be created for function
returns or arguments.

To keep everything consistent I've added new nodes for fptosi as well.

Reviewed By: luismarques

Differential Revision: https://reviews.llvm.org/D106346
2021-07-24 10:50:43 -07:00
Craig Topper 12d51f95fe [RISCV] Implement lround*/llround*/lrint*/llrint* with fcvt instruction with -fno-math-errno
These are fp->int conversions using either RMM or dynamic rounding modes.

The lround and lrint opcodes have a return type of either i32 or
i64 depending on sizeof(long) in the frontend which should follow
xlen. llround/llrint should always return i64 so we'll need a libcall
for those on rv32.

The frontend will only emit the intrinsics if -fno-math-errno is in
effect otherwise a libcall will be emitted which will not use
these ISD opcodes.

gcc also does this optimization.

Reviewed By: arcbbb

Differential Revision: https://reviews.llvm.org/D105206
2021-07-06 11:43:22 -07:00
Craig Topper 58323be415 [RISCV] Cleanup instruction formats used for B extension ternary operations.
Rename RVInstR4 as used by F/D/Zfh extensions to RVInstR4Frm.
Introduce new RVInstR4 that takes funct3 as a parameter.

Add new format classes for FSRI and FSRIW instead of trying to
bend RVInstR4 to use a shamt overlayed on rs2 and funct2.

Reviewed By: frasercrmck

Differential Revision: https://reviews.llvm.org/D100427
2021-05-06 08:59:05 -07:00
Craig Topper 023b243d1d [RISCV] Cleanup up the spec version references around fmaxnum/fminnum.
This previously made references to 2.3-draft which was a short
lived version number in 2017. It was replaced by date based
versions leading up to ratification.

This patch uses the latest ratified version number and just says
what the behavior is. Nothing here is in flux.

Reviewed By: frasercrmck

Differential Revision: https://reviews.llvm.org/D100878
2021-04-21 14:50:29 -07:00
Serge Pavlov d20a2376d8 [RISCV] Introduce floating point control and state registers
New registers FRM, FFLAGS and FCSR was defined. They represent
corresponding system registers. The new registers are necessary to
properly order floating point instructions in non-default modes.

Differential Revision: https://reviews.llvm.org/D99083
2021-04-21 12:55:30 +07:00
Craig Topper 4d5ee71b52 [RISCV] Merge FMulAdd and FMulSub scheduler classes to a single FMA scheduler class. NFC
It's unlikely that FMADD and FMSUB would have different scheduling
information so merge them.

Reviewed By: HsiangKai

Differential Revision: https://reviews.llvm.org/D99140
2021-03-26 16:37:20 -07:00
Craig Topper 9bde29629d [RISCV] Use a ComplexPattern for zexti32 to match sexti32.
We just started using a ComplexPattern for sexti32. This updates
zexti32 to match.

Reviewed By: luismarques

Differential Revision: https://reviews.llvm.org/D97231
2021-02-24 16:06:29 -08:00
Craig Topper 3231607ce9 [RISCV] Have sexti32 also recognize AssertZExt from types smaller than i32.
An i64 AssertZExt from a type smaller than i32 has at least 33
leading zeros which mean it has at least 33 sign bits.

Since we have a couple patterns that use two sexti32, I've
switched to a ComplexPattern so tablegen didn't have to generate
9 different permutations.

As noted in the FIXME, maybe we should just call computeNumSignBits,
but we don't have tests that benefit from that yet.

Reviewed By: luismarques

Differential Revision: https://reviews.llvm.org/D97130
2021-02-22 14:56:22 -08:00
Craig Topper 29b894a8d3 [RISCV] Add expicit i32/i64 types to RV32 or RV64 only isel patterns. NFC
This stops tablegen from generating patterns with the opposite type
in the opposite HwMode. This just adds wasted bytes to the isel table.

This reduces the isel table by about 1800 bytes.
2021-02-15 14:36:05 -08:00
Craig Topper a1ae3c6ac9 [RISCV][LegalizeDAG] Expand SETO and SETUO comparisons. Teach LegalizeDAG to expand SETUO expansion when UNE isn't legal.
If SETUNE isn't legal, UO can use the NOT of the SETO expansion.

Removes some complex isel patterns. Most of the test changes are
from using XORI instead of SEQZ.

Differential Revision: https://reviews.llvm.org/D92008
2020-12-10 09:15:52 -08:00
Craig Topper 03fc4f2e9a [RISCV] Use fcvt.h/d/f.w if the input is an assertsexti32 not just when the input is sext_inreg. 2020-12-04 18:40:02 -08:00
Craig Topper a18d5e3e9f [RISCV] Merge FMV_H_X_RV32/FMV_H_X_RV64 into a single opcode. Same with FMV_X_ANYEXTH_RV32/RV64
Rather than having a different opcode for RV32 and RV64. Let's just say the integer type is XLenVT and use a single opcode for both modes.

Differential Revision: https://reviews.llvm.org/D92538
2020-12-03 11:12:40 -08:00
Craig Topper f325b4bbce [RISCV] Replace sexti32/zexti32 in isel patterns where only one part of their PatFrags can match. NFCI
We had an zexti32 after a sign_extend_inreg. The AND X, 0xffffffff
part of the zexti32 should never occur since SimplifyDemandedBits
from the sign_extend_inreg would have removed it.

We also had sexti32 as the root node of a pattern, but SelectionDAGISel
matches assertsext early before the tablegen based patterns are
evaluated.
2020-11-27 11:37:25 -08:00
Craig Topper 4252f7773a [SelectionDAG][ARM][AArch64][Hexagon][RISCV][X86] Add SDNPCommutative to fma and fmad nodes in tablegen. Remove explicit commuted patterns from targets.
X86 was already specially marking fma as commutable which allowed
tablegen to autogenerate commuted patterns. This moves it to the target
independent definition and fix up the targets to remove now
unneeded patterns.

Unfortunately, the tests change because the commuted version of
the patterns are generating operands in a different than the
explicit patterns.

Differential Revision: https://reviews.llvm.org/D91842
2020-11-23 10:09:20 -08:00
Craig Topper 741b04b0b7 [RISCV] Only enable GPR<->FPR32 bitconvert isel patterns on RV32. NFCI
Bitconvert requires the bitwidth to match on both sides. On RV64
the GPR size is i64 so bitconvert between f32 isn't possible. The
node should never be generated so the pattern won't ever match, but
moving the patterns under IsRV32 makes it more obviously impossible.
It also moves it to a similar location to the patterns for the
custom nodes we use for RV64.
2020-11-05 16:15:25 -08:00
Craig Topper defe11866a [RISCV] Add isel patterns for fnmadd/fnmsub with an fneg on the second operand instead of the first.
The multiply part of FMA is commutable, but TargetSelectionDAG.td
doesn't have it marked as commutable so tablegen won't automatically
create the additional patterns.

So manually add commuted patterns.
2020-11-05 14:00:25 -08:00
Sam Elliott a4a9a1f671 [RISCV] Add patterns for checking isnan
Summary:
This patch addresses some weird assembly sequences we were seeing during
comparing floats. In particular, comparing a float to itself tells you whether
it is NaN or not, which we were doing correctly, but with an extra unneeded
`and` instruction.

This patch specialises the existing patterns to remove the `and` instructions
when both their operands are the same.

Reviewed By: luismarques, asb

Differential Revision: https://reviews.llvm.org/D78908
2020-05-02 15:01:04 +01:00
Sam Elliott 09f6b9792b [RISCV][NFC] Remove Duplicated F Extension Patterns 2020-04-30 11:35:49 +01:00
Roger Ferrer Ibanez 3c24aee7ee [RISCV] Select +0.0 immediate using fmv.{w,d}.x / fcvt.d.w
Floating point positive zero can be selected using fmv.w.x / fmv.d.x /
fcvt.d.w and the zero source register.

Differential Revision: https://reviews.llvm.org/D75729
2020-03-20 09:42:24 +00:00
Shiva Chen c3d981aeba [RISCV] Add new SchedRead SchedWrite
The patch fixes some typos and introduces ReadFMemBase, ReadFSGNJ32,
ReadFSGNJ64, WriteFSGNJ32, WriteFSGNJ64, ReadFMinMax32, ReadFMinMax64,
WriteFMinMax32, WriteFMinMax64, so the target CPU with different pipeline model
could use them to describe latency.

Differential Revision: https://reviews.llvm.org/D75515
2020-03-10 00:12:27 +08:00
Kai Wang 838a28e234 [RISCV] Scheduler description for the Rocket core
Pipeline scheduler model for the RISC-V Rocket micro-architecture using the
MIScheduler interface.  Support for both 32 and 64-bit Rocket cores is
implemented.

Differential revision: https://reviews.llvm.org/D68685
2020-01-23 19:36:47 -06:00
Edward Jones f5177a7db4 [RISCV] Add obsolete aliases of fscsr, frcsr (fssr, frsr)
These old aliases were renamed, but are still used by some projects (eg newlib).

Differential Revision: https://reviews.llvm.org/D68392

llvm-svn: 373618
2019-10-03 15:47:28 +00:00
Sam Elliott 6884d5e040 [RISCV][NFC] Replace hard-coded CSR duplication with symbolic references
Reviewers: asb, lenary

Reviewed By: asb, lenary

Subscribers: MaskRay, hiraditya, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, kito-cheng, shiva0217, zzheng, edward-jones, rogfer01, MartinMosbeck, brucehoult, the_o, rkruppe, PkmX, jocewei, psnobl, benna, Jim, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64139

Patch by James Clarke (jrtc27)

llvm-svn: 365195
2019-07-05 12:16:40 +00:00
Luis Marques 3091884e25 [RISCV] Add seto pattern expansion
Adds a `seto` pattern expansion. Without it the lowerings of `fcmp one` and 
`fcmp ord` would be inefficient due to an unoptimized double negation.

Differential Revision: https://reviews.llvm.org/D59699

llvm-svn: 357378
2019-04-01 09:54:14 +00:00
Alex Bradbury 047170cfc3 [RISCV] Add implied zero offset load/store alias patterns
Allow load/store instructions with implied zero offset for compatibility with
GNU assembler.

Differential Revision: https://reviews.llvm.org/D57141
Patch by James Clarke.

llvm-svn: 354581
2019-02-21 14:09:34 +00:00
Kito Cheng 303217e8b4 [RISCV] Implement pseudo instructions for load/store from a symbol address.
Summary:
Those pseudo-instructions are making load/store instructions able to
load/store from/to a symbol, and its always using PC-relative addressing
to generating a symbol address.

Reviewers: asb, apazos, rogfer01, jrtc27

Differential Revision: https://reviews.llvm.org/D50496

llvm-svn: 354430
2019-02-20 03:31:32 +00:00
Alex Bradbury d834d8301d [RISCV] Add RV64F codegen support
This requires a little extra work due tothe fact i32 is not a legal type. When
call lowering happens post-legalisation (e.g. when an intrinsic was inserted
during legalisation). A bitcast from f32 to i32 can't be introduced. This is
similar to the challenges with RV32D. To handle this, we introduce
target-specific DAG nodes that perform bitcast+anyext for f32->i64 and
trunc+bitcast for i64->f32.

Differential Revision: https://reviews.llvm.org/D53235

llvm-svn: 352807
2019-01-31 22:48:38 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00