Commit Graph

9 Commits

Author SHA1 Message Date
Craig Topper b894a9fb23 [RISCV] Optimize select_cc after fp compare expansion
Some FP compares expand to a sequence ending with (xor X, 1) to invert the result. If
the consumer is a select_cc we can likely get rid of this xor by fixing
up the select_cc condition.

This patch combines (select_cc (xor X, 1), 0, setne, trueV, falseV) -
(select_cc X, 0, seteq, trueV, falseV) if we can prove X is 0/1.

Reviewed By: lenary

Differential Revision: https://reviews.llvm.org/D94546
2021-01-14 13:41:40 -08:00
Craig Topper 03c8d6a0c4 [LegalizeDAG][RISCV][PowerPC][AMDGPU][WebAssembly] Improve expansion of SETONE/SETUEQ on targets without SETO/SETUO.
If SETO/SETUO aren't legal, they'll be expanded and we'll end up
with 3 comparisons.

SETONE is equivalent to (SETOGT || SETOLT)
so if one of those operations is supported use that expansion. We
don't need both since we can commute the operands to make the other.

SETUEQ can be implemented with !(SETOGT || SETOLT) or (SETULE && SETUGE).
I've only implemented the first because it didn't look like most of the
affected targets had legal SETULE/SETUGE.

Reviewed By: frasercrmck, tlively, nemanjai

Differential Revision: https://reviews.llvm.org/D94450
2021-01-12 10:45:03 -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
Luis Marques 3d0fbafd0b [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
2019-09-17 11:15:35 +00:00
Luis Marques 2d550d19b3 Revert Patch from Phabricator
This reverts r372092 (git commit e38695a025)

llvm-svn: 372104
2019-09-17 10:52:09 +00:00
Luis Marques e38695a025 Patch from Phabricator
llvm-svn: 372092
2019-09-17 09:43:08 +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 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
Alex Bradbury 65d6ea5e68 [RISCV] Codegen support for RV32F floating point comparison operations
This patch also includes extensive tests targeted at select and br+fcmp IR
inputs. A sequence of br+fcmp required support for FPR32 registers to be added
to RISCVInstrInfo::storeRegToStackSlot and
RISCVInstrInfo::loadRegFromStackSlot.

llvm-svn: 328104
2018-03-21 15:11:02 +00:00