Commit Graph

8 Commits

Author SHA1 Message Date
Sam Elliott 969e703427 [RISCV] Support Constant Pools in Load/Store Peephole
Summary:
RISC-V uses a post-select peephole pass to optimise
`(load/store (ADDI $reg, %lo(addr)), 0)` into `(load/store $reg, %lo(addr))`.
This peephole wasn't firing for accesses to constant pools, which is how we
materialise most floating point constants.

This adds support for the constantpool case, which improves code generation for
lots of small FP loading examples. I have not added any tests because this
structure is well-covered by the `fp-imm.ll` testcases, as well as almost
all other uses of floating point constants in the RISC-V backend tests.

Reviewed By: luismarques, asb

Differential Revision: https://reviews.llvm.org/D79523
2020-05-11 19:20:38 +01:00
Sam Elliott 3242e5653a Revert "[RISCV] Support Constant Pools in Load/Store Peephole"
This reverts commit fe69dfebcf, due to
a slight change in the API.
2020-05-11 18:14:05 +01:00
Sam Elliott fe69dfebcf [RISCV] Support Constant Pools in Load/Store Peephole
Summary:
RISC-V uses a post-select peephole pass to optimise
`(load/store (ADDI $reg, %lo(addr)), 0)` into `(load/store $reg, %lo(addr))`.
This peephole wasn't firing for accesses to constant pools, which is how we
materialise most floating point constants.

This adds support for the constantpool case, which improves code generation for
lots of small FP loading examples. I have not added any tests because this
structure is well-covered by the `fp-imm.ll` testcases, as well as almost
all other uses of floating point constants in the RISC-V backend tests.

Reviewed By: luismarques, asb

Differential Revision: https://reviews.llvm.org/D79523
2020-05-11 18:01:18 +01:00
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
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 80c8eb7696 [RISCV] Add codegen for RV32F floating point load/store
As part of this, add support for load/store from the constant pool. This is
used to materialise f32 constants.

llvm-svn: 327979
2018-03-20 13:26:12 +00:00