aarch64: Add support for `fnmadd`/`fmsub`/`fnmsub`
afonso360 opened this issue · comments
👋 Hey,
Feature
Add support for the fnmadd / fmsub / fnmsub instructions in the aarch64 backend.
Benefit
This improves instruction selection quality for a few special fma cases.
Implementation
We already have support for the scalar fmadd instruction here. So we adding support for these instructions should be a matter of introducing the new opcodes and implementing lowering rules similar to what already exists today.
Something similar was done in #8588 for the RISC-V backend. If anyone needs help implementing this, let me know!