FRFLAGS - RISC-V instruction reference

frflagsRead FP exception flags Pseudo-instruction
Reads the FP exception flags into t1.
RISC-V manual: csrrs 
Used in Floating point and the F and D extensionsRISC-V assembly
 
Forms  frflags   
Operands t1 Any integer register, x0 to x31, or its named alias, such as zero, t0 or t6. 
 # Initialize fflags, then use frflags to read its old value or update it.
.text
li t3, 0
csrw t3, fflags
frflags t1
# t1=0 because fflags was cleared immediately above.