Though the ABI / call-convention for rv32e has not be defined clear by the riscv organization.
But besides that, is it possible to partial support it by adding target feature FeatureReserveX16—FeatureReserveX31 to the FeatureRV32E ?
: SubtargetFeature<“d”, “HasStdExtD”, “true”,
“‘D’ (Double-Precision Floating-Point)”,
FeatureStdExtD implies FeatureStdExtF, we can make FeatureRV32E implies FeatureReserveX16—FeatureReserveX31 ?
Is this a proper way to tell the register allocator do not use X16-X31 ?