Encoding:

COP1

010001

MF

00000

rt

fs

0

000 0000 0000

6

5

5

5

11

Format: 

MFC1 rt, fs

MIPS32

Move Word From Floating Point

Purpose:

Move Word From Floating Point

To copy a word from an FPU (CP1) general register to a GPR.

Description: 

 GPR[rt] = FPR[fs]

The contents of FPR fs are sign-extended and loaded into general register rt.

Restrictions:

Operation: 

data = ValueFPR(fs, UNINTERPRETED_WORD)31..0
GPR[rt] = sign_extend(data)

Exceptions:

Coprocessor Unusable, Reserved Instruction

Historical Information:

For MIPS I, MIPS II, and MIPS III the contents of GPR rt are UNPREDICTABLE for the instruction immediately following MFC1.