_WriteCoProcessor

9/7/2007

This instruction causes the specified ARM registers to transfer values to coprocessor registers.

Syntax

void _WriteCoProcessor(
  __int64 Arg1,
  int Arg2
);

Parameters

• Arg1
  [in] Values to be written to coprocessor.

• Arg2
  [in] Coprocessor number. This should be zero.

Return Values

None.

Remarks

For the ARM XScale processor, the compiler translates this intrinsic into the MAR assembly instruction. MAR is disassembled as the MCRR instruction.

For the ARM DSP-enhanced processor, the compiler translates this intrinsic into the MCRR assembly instruction.

The XScale and the DSP-enhanced ARM microprocessors implement this instruction in two slightly different ways.

• ARM XScale implementation
  This instruction moves the value in register RdLo to bits [31:0] of the 40-bit accumulator (acc0), and moves bits [7:0] of the value in register RdHi into bits [39:32] of acc0.
• ARM DSP-enhanced implementation
  This instruction causes the two general-purpose registers Rd and Rn to transfer values to the coprocessor.

Requirements

Routine	Required header	Architecture
_WriteCoProcessor	<armintr.h>	ARM10, ARM-DSP

See Also

Reference

ARM XSCALE Intrinsic Functions
ARM DSP-enhanced Intrinsic Functions
_ReadCoProcessor