On 6/22/23 07:03, Robin Dapp wrote:
Hi,
when working on FP widening/narrowing I realized the Zvfhmin handling
is not ideal right now: We use the "enabled" insn attribute to disable
instructions not available with Zvfhmin (but only with Zvfh).
However, "enabled == 0" only disables insn alternatives, in our case all
of them when the mode is a HFmode. The insn itself remains available
(e.g. for combine to match) and we end up with an insn without alternatives
that reload cannot handle --> ICE.
The proper solution is to disable the instruction for the respective
mode altogether. This patch achieves this by splitting the VF as well
as VWEXTF iterators into variants with TARGET_ZVFH and
TARGET_VECTOR_ELEN_FP_16 (which is true when either TARGET_ZVFH or
TARGET_ZVFHMIN are true). Also, VWCONVERTI, VHF and VHF_LMUL1 need
adjustments.
Regards
Robin
gcc/ChangeLog:
* config/riscv/autovec.md: VF_AUTO -> VF.
* config/riscv/vector-iterators.md: Introduce VF_ZVFHMIN,
VWEXTF_ZVFHMIN and use TARGET_ZVFH in VWCONVERTI, VHF and
VHF_LMUL1.
* config/riscv/vector.md: Use new iterators.
OK for the trunk. Thanks for walking everyone through the issues here.
jeff
