Commit Graph

22 Commits

Author SHA1 Message Date
Craig Topper b7b4f4cbc3 [RISCV] Make scalable vector FMA commutable for register allocation.
This adds support for commuting operands and converting between
vfmadd and vfmacc to avoid register copies.

To avoid messing up intrinsic behavior, I've added new pseudo
instructions that have the isCommutable flag set. These pseudos also
force a tail agnostic policy. The intrinsic version still use
the tail undisturbed policy.

For best results it looks like we need to start with fmadd and only
pick fmacc if its beneficial. MachineCSE commutes without contraining
the operands and then commutes back if it didn't help with CSE. So
I've made sure that when the operand choice isn't constrained, we
will keep fmadd for MachineCSE and when it does the second commute,
we get back the original instruction.

Reviewed By: frasercrmck

Differential Revision: https://reviews.llvm.org/D95800
2021-02-08 10:05:33 -08:00
Hsiangkai Wang b8921af63b [RISCV] Update V instructions constraints to conform to v1.0
Upgrade RISC-V V extension to v1.0-08a0b46.
Update instruction constraints to conform to v1.0.

Differential Revision: https://reviews.llvm.org/D93612
2021-01-22 01:15:55 +08:00
Craig Topper 5cf73dca77 [RISCV] Convert most of the information about RVV Pseudos into bits in TSFlags.
This patch moves all but the BaseInstr to bits in TSFlags.

For the index fields, we can just use a bit to indicate their presence.
The locations of the operands are well defined.

This reduces the llc binary by about 32K on my build. It also
removes the binary search of the table from the custom inserter.
Instead we just check that the SEW op is present.

Reviewed By: rogfer01

Differential Revision: https://reviews.llvm.org/D94375
2021-01-10 19:15:45 -08:00
Craig Topper 76202f09b5 [RISCV] Improve VMConstraint checking on more unary and nullary instructions.
We weren't consistently marking unary instructions as OneInput
and vid.v is really ZeroInput but we had no way to mark that.

This patch improves this by removing the error prone OneInput constraint.
Instead we just always look for the mask in the last operand.

It appears that the "CheckReg" variable used for the check on the broken
instruction was unitialized or garbage because it was also used for
VS1/VS2 constraints. I've scoped the variable locally to each check now.

I've gone through and set NoConstraint on instructions that don't have
a real VMConstraint and don't have a mask as the last operand.

I've also removed the unused enum values in RISCVBaseInfo.h. We
never use them in C++ and we have separate versions in a td file.

Reviewed By: HsiangKai

Differential Revision: https://reviews.llvm.org/D93784
2020-12-26 18:47:59 -08:00
Hsiangkai Wang 47a4a27f47 Upgrade MC to v0.9.
Differential revision: https://reviews.llvm.org/D80802
2020-08-01 07:42:06 +08:00
Hsiangkai Wang 66da87dcba [RISCV] Assemble/Disassemble v-ext instructions.
Assemble/disassemble RISC-V V extension instructions according to
latest version spec in https://github.com/riscv/riscv-v-spec/.

I have tested this patch using GNU toolchain. The encoding is aligned
to GNU assembler output. In this patch, there is a test case for each
instruction at least.

The V register definition is just for assemble/disassemble. Its type
is not important in this stage. I think it will be reviewed and modified
as we want to do codegen for scalable vector types.

This patch does not include Zvamo, Zvlsseg, and Zvediv.

Differential revision: https://reviews.llvm.org/D69987
2020-06-28 00:54:07 +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
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
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
Alex Bradbury b4a64cede8 [RISCV][NFC] Define and use the new CA instruction format
The RISC-V ISA manual was updated on 2018-11-07 (commit 00557c3) to define a 
new compressed instruction format, RVC format CA (no actual instruction 
encodings were changed). This patch updates the RISC-V backend to define the 
new format, and to use it in the relevant instructions.

Differential Revision: https://reviews.llvm.org/D54302
Patch by Luís Marques.

llvm-svn: 347043
2018-11-16 10:33:23 +00:00
Alex Bradbury 6a4b5441e4 [RISCV] AsmParser support for the li pseudo instruction
The implementation follows the MIPS backend and expands the pseudo instruction 
directly during asm parsing. As the result, only real MC instructions are 
emitted to the MCStreamer. The actual expansion to real instructions is 
similar to the expansion performed by the GNU Assembler.

This patch supersedes D41949.

Differential Revision: https://reviews.llvm.org/D46118
Patch by Mario Werner.

llvm-svn: 334203
2018-06-07 15:35:47 +00:00
Alex Bradbury 099c720426 Revert "[RISCV] implement li pseudo instruction"
Reverts rL330224, while issues with the C extension and missed common
subexpression elimination opportunities are addressed. Neither of these issues
are visible in current RISC-V backend unit tests, which clearly need
expanding.

llvm-svn: 330281
2018-04-18 19:02:31 +00:00
Alex Bradbury 480b7bc906 [RISCV] implement li pseudo instruction
The implementation follows the MIPS backend and expands the
pseudo instruction directly during asm parsing. As the result, only
real MC instructions are emitted to the MCStreamer. Additionally,
PseudoLI instructions are emitted during codegen. The actual
expansion to real instructions is performed during MI to MC lowering
and is similar to the expansion performed by the GNU Assembler.

Differential Revision: https://reviews.llvm.org/D41949
Patch by Mario Werner.

llvm-svn: 330224
2018-04-17 21:56:40 +00:00
Alex Bradbury 9f6aec4b7a [RISCV] MC layer support for load/store instructions of the C (compressed) extension
Differential Revision: https://reviews.llvm.org/D40001
    
Patch by Shiva Chen.

llvm-svn: 320037
2017-12-07 12:50:32 +00:00
Alex Bradbury a6e6248307 [RISCV] MC layer support for the standard RV64I instructions
llvm-svn: 320024
2017-12-07 10:53:48 +00:00
Alex Bradbury 0d6cf90663 [RISCV] MC layer support for the standard RV32F instruction set extension
The most interesting part of this patch is probably the handling of 
rounding mode arguments. Sadly, the RISC-V assembler handles floating point 
rounding modes as a special "argument" when it would be more consistent to 
handle them like the atomics, opcode suffixes. This patch supports parsing 
this optional parameter, using InstAlias to allow parsing these floating point 
instructions when no rounding mode is specified.

Differential Revision: https://reviews.llvm.org/D39893

llvm-svn: 320020
2017-12-07 10:26:05 +00:00
Alex Bradbury 8c345c5aa9 [RISCV] MC layer support for the standard RV32A instruction set extension
llvm-svn: 317791
2017-11-09 15:00:03 +00:00
Alex Bradbury ee7c7ecd03 [RISCV] Prepare for the use of variable-sized register classes
While parameterising by XLen, also take the opportunity to clean up the 
formatting of the RISCV .td files.

This commit unifies the in-tree code with my patchset at 
<https://github.com/lowrisc/riscv-llvm>.

llvm-svn: 316159
2017-10-19 14:29:03 +00:00
Alex Bradbury 9d3f12501a [RISCV] Add common fixups and relocations
%lo(), %hi(), and %pcrel_hi() are supported and test cases have been added to 
ensure the appropriate fixups and relocations are generated. I've added an 
instruction format field which is used in RISCVMCCodeEmitter to, for 
instance, tell whether it should emit a lo12_i fixup or a lo12_s fixup 
(RISC-V has two 12-bit immediate encodings depending on the instruction 
type).

Differential Revision: https://reviews.llvm.org/D23568

llvm-svn: 314389
2017-09-28 08:26:24 +00:00
Alex Bradbury 8ab4a9696a [RISCV] Add support for disassembly
This Disassembly support allows for 'round-trip' testing, and rv32i-valid.s
has been updated appropriately.

Differential Revision: https://reviews.llvm.org/D23567

llvm-svn: 313486
2017-09-17 14:36:28 +00:00
Alex Bradbury 6be16fbfb8 [RISCV] Pseudo instructions are isCodeGenOnly, have blank asmstr
llvm-svn: 295027
2017-02-14 05:17:23 +00:00
Alex Bradbury 24d9b13b36 [RISCV 4/10] Add basic RISCV{InstrFormats,InstrInfo,RegisterInfo,}.td
For now, only add instruction definitions for basic ALU operations. Our 
initial target is a working MC layer rather than codegen, so appropriate 
SelectionDAG patterns will come later.

Differential Revision: https://reviews.llvm.org/D23561

llvm-svn: 285769
2016-11-01 23:40:28 +00:00