VFPFMRX r6, FPINST @ FPINST (always there, rev0 onwards)
tst r1, #FPEXC_FPV2 @ is there an FPINST2 to read?
VFPFMRX r8, FPINST2, NE @ FPINST2 if needed - avoids reading
@ nonexistant reg on rev0
VFPFSTMIA r4 @ save the working registers
add r4, r4, #8*16+4
VFPFMRX r6, FPINST @ FPINST (always there, rev0 onwards)
tst r1, #FPEXC_FPV2 @ is there an FPINST2 to read?
VFPFMRX r8, FPINST2, NE @ FPINST2 if needed - avoids reading
@ nonexistant reg on rev0
VFPFSTMIA r4 @ save the working registers
add r4, r4, #8*16+4