Encoding:

Format:

BC2T cc, offset

Purpose:

Branch on COP2 True

To test a COP2 condition code and do a PC-relative conditional branch.

Description:

 if COP2Condition(cc) = 1 then branch

An 18-bit signed offset (the 16-bit offset field shifted left 2 bits) is added to the address of the instruction following the branch (not the branch itself) in the branch delay slot to form a PC-relative effective target address. If the COP2 condition specified by cc is true (1), the program branches to the effective target address after the instruction in the delay slot is executed.

Restrictions:

Processor operation is UNPREDICTABLE if a control transfer instruction (CTI) is placed in the delay slot of a branch or jump.

Availability and Compatibility:

This instruction has been removed in Release 6.

Operation:

I:    condition = COP2Condition(cc) = 1
      target_offset = (offset15)GPRLEN-(16+2) || offset || 02
I+1:  if condition then
         PC = PC + target_offset
      endif

Exceptions:

Coprocessor Unusable, Reserved Instruction

Programming Notes:

With the 18-bit signed instruction offset, the conditional branch range is ± 128 KBytes. Use jump (J) or jump register

(JR) to branch to addresses outside this range.

This instruction has been replaced by the BC2NEZ instruction. Refer to the ‘BC2NEZ’ instruction in this manual for more information.