Register Guide
RISC-V fflags / fflags Register: Floating-point accrued exception flags
fflags is the floating-point accrued exception flags register, recording NV, DZ, OF, UF, NX exception flags from FP operations.
ABI name: fflags; physical register: fflags.
Save rule: Saved by software when context requires.
Read it through its psABI role first, then inspect how each instruction reads or writes it.
Physical Name fflagsABI Name fflagsSave Rule Saved by software when context requires
Role
Floating-point accrued exception flags
Convention
Architectural state / CSR semantics
Remember This First
The calling convention listed for this entry is: Architectural state / CSR semantics.
RISC-V Floating-Point ISA Reference
ABI register
fflags is the floating-point accrued exception flags register, recording NV, DZ, OF, UF, NX exception flags from FP operations.
Preserved across calls: Saved by software when context requires
RISC-V Unprivileged ISA Manual, floating-point CSRsWhen It Fits Best
- - Use it according to the documented role: Floating-point accrued exception flags.
- - Consult the applicable ISA or ABI specification for concrete read, write, or execution semantics.
When Not To Use It This Way
- - Do not apply the integer temporary-register t* rules to this entry.
- - Do not infer behavior not defined by this page or the applicable specification from the ABI name.
What Happens Around A Call
1
The calling convention listed for this entry is: Architectural state / CSR semantics.
2
The save rule listed for this entry is: Saved by software when context requires.
Read The Documented Role
Examples explain the rule, not a complete program# fflags / fflags
# Floating-point accrued exception flags
# Architectural state / CSR semantics