search for: iscommuatbl

Thanks to Anton. Frankly said i don't know the exact meaning and purpose of 'isCommutable'. By my opinion "add.w r6, r7" != "add.w r7, r6", so we shouldn't set isCommutable = 1. Who would like give an example to demonstrate what benifit it has if 'isCommuatble=1' in instruction selection, register allocation or other process? Regards 2009/12/7, Anton Korobeynikov <anton at korobeynikov.info>: > > Hello > > > *** Another question: Why set isCommutable = 1 in ADD16rr but NOT set in > > ADD16ri? > Because all msp430 i...

Hello > How can i tell the system X=A*B + C == X = B*A + C == X=C+A*B == X=C+B*A by > property 'isCommutable'? Is it necessary to do that? Most probably you will need to write a special hook to commute this instruction. However, everything depends on your target (e.g. if there is an output register tied to one of the input). > *** Another question: Why set isCommutable = 1 in

Hi everyone, I practice writing target description file with MSP430 reference. I add a multiply-and-add instruction as below: let isTwoAddress=1 in { def MULADD:Pseudo<(out GR16:$dst), (ins GR16:$src1, GR16:$src2, GR16:$src3), "muladd\t{$dst, $src2, $src3}", [(set GR16:$dst, (add GR16:$src1, (mul GR16:$src2,