Transfer contents between an ARM register and a NEON and VFP system register.
Syntax
VMRS{cond} Rd, extsysreg
VMSR{cond}extsysreg,Rd
where:
condis an optional condition code.
extsysregis the NEON and VFP system register, usually
FPSCR,FPSID, orFPEXC.Rdis the ARM register.
RdIt can be
APSR_nzcv, ifextsysregFPSCR. In this case, the floating-point status flags are transferred into the corresponding flags in the ARM APSR.
The VMRS instruction transfers the contents of extsysregRd
The VMSR instruction transfers the contents of Rdextsysreg
Note
These instructions stall the ARM until all current NEON or VFP operations complete.
VMRS r2,FPCID
VMRS APSR_nzcv, FPSCR ; transfer FP status register to ARM APSR
VMSR FPSCR, r4
- Concepts
Using the Assembler:
- Reference:
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