RISC-V ISA Explorer · Float & Numerics (Zf*)

Zfinx: FP in Integer Regs (F)

Ratified 2021-11 · version 1.0.0

Single-precision arithmetic carried out in the integer registers, cutting the cost of small cores.

Typical use: Single precision with no separate FP register file

Specification

Open Zfinx in the explorer

Dependencies

Requires

Zicsr

Incompatible with

Required by

Instructions (26)

Mnemonic	Name	Encoding	Match	Mask
`FADD.S`	Floating-Point Add Single-Precision	`0000000------------------1010011`	`0x53`	`0xfe00007f`
`FCLASS.S`	Floating-Point Classify Single-Precision	`111000000000-----001-----1010011`	`0xe0001053`	`0xfff0707f`
`FCVT.L.S`	Floating-Point Convert Single-Precision to Long	`110000000010-------------1010011`	`0xc0200053`	`0xfff0007f`
`FCVT.LU.S`	Floating-Point Convert Single-Precision to Unsigned Long	`110000000011-------------1010011`	`0xc0300053`	`0xfff0007f`
`FCVT.S.L`	Floating-Point Convert Long to Single-Precision	`110100000010-------------1010011`	`0xd0200053`	`0xfff0007f`
`FCVT.S.LU`	Floating-Point Convert Unsigned Long to Single-Precision	`110100000011-------------1010011`	`0xd0300053`	`0xfff0007f`
`FCVT.S.W`	Floating-Point Convert Word to Single-Precision	`110100000000-------------1010011`	`0xd0000053`	`0xfff0007f`
`FCVT.S.WU`	Floating-Point Convert Unsigned Word to Single-Precision	`110100000001-------------1010011`	`0xd0100053`	`0xfff0007f`
`FCVT.W.S`	Floating-Point Convert Single-Precision to Word	`110000000000-------------1010011`	`0xc0000053`	`0xfff0007f`
`FCVT.WU.S`	Floating-Point Convert Single-Precision to Unsigned Word	`110000000001-------------1010011`	`0xc0100053`	`0xfff0007f`
`FDIV.S`	Floating-Point Divide Single-Precision	`0001100------------------1010011`	`0x18000053`	`0xfe00007f`
`FEQ.S`	Floating-Point Equal Single-Precision	`1010000----------010-----1010011`	`0xa0002053`	`0xfe00707f`
`FLE.S`	Floating-Point Less Than or Equal Single-Precision	`1010000----------000-----1010011`	`0xa0000053`	`0xfe00707f`
`FLT.S`	Floating-Point Less Than Single-Precision	`1010000----------001-----1010011`	`0xa0001053`	`0xfe00707f`
`FMADD.S`	Floating-Point Multiply-Add Single-Precision	`-----00------------------1000011`	`0x43`	`0x600007f`
`FMAX.S`	Floating-Point Maximum-Number Single-Precision	`0010100----------001-----1010011`	`0x28001053`	`0xfe00707f`
`FMIN.S`	Floating-Point Minimum-Number Single-Precision	`0010100----------000-----1010011`	`0x28000053`	`0xfe00707f`
`FMSUB.S`	Floating-Point Multiply-Subtract Single-Precision	`-----00------------------1000111`	`0x47`	`0x600007f`
`FMUL.S`	Floating-Point Multiply Single-Precision	`0001000------------------1010011`	`0x10000053`	`0xfe00007f`
`FNMADD.S`	Floating-Point Negate-Multiply-Add Single-Precision	`-----00------------------1001111`	`0x4f`	`0x600007f`
`FNMSUB.S`	Floating-Point Negate-Multiply-Subtract Single-Precision	`-----00------------------1001011`	`0x4b`	`0x600007f`
`FSGNJ.S`	Floating-Point Sign-Inject Single-Precision	`0010000----------000-----1010011`	`0x20000053`	`0xfe00707f`
`FSGNJN.S`	Floating-Point Sign-Inject Negate Single-Precision	`0010000----------001-----1010011`	`0x20001053`	`0xfe00707f`
`FSGNJX.S`	Floating-Point Sign-Inject XOR Single-Precision	`0010000----------010-----1010011`	`0x20002053`	`0xfe00707f`
`FSQRT.S`	Floating-Point Square Root Single-Precision	`010110000000-------------1010011`	`0x58000053`	`0xfff0007f`
`FSUB.S`	Floating-Point Subtract Single-Precision	`0000100------------------1010011`	`0x8000053`	`0xfe00007f`