8.21.1.2 Instruction Set Extention Options

These options enables or disables the use of extensions over the base line instruction set as introduced by the first PDP-11 CPU: the KA11. Most options come in two variants: a -mextension that enables extension, and a -mno-extension that disables extension.

The default is to enable all extensions.

-mall | -mall-extensions

Enable all instruction set extensions.

-mno-extensions

Disable all instruction set extensions.

-mcis | -mno-cis

Enable (or disable) the use of the commersial instruction set, which consists of these instructions: ADDNI, ADDN, ADDPI, ADDP, ASHNI, ASHN, ASHPI, ASHP, CMPCI, CMPC, CMPNI, CMPN, CMPPI, CMPP, CVTLNI, CVTLN, CVTLPI, CVTLP, CVTNLI, CVTNL, CVTNPI, CVTNP, CVTPLI, CVTPL, CVTPNI, CVTPN, DIVPI, DIVP, L2DR, L3DR, LOCCI, LOCC, MATCI, MATC, MOVCI, MOVC, MOVRCI, MOVRC, MOVTCI, MOVTC, MULPI, MULP, SCANCI, SCANC, SKPCI, SKPC, SPANCI, SPANC, SUBNI, SUBN, SUBPI, and SUBP.

-mcsm | -mno-csm

Enable (or disable) the use of the CSM instruction.

-meis | -mno-eis

Enable (or disable) the use of the extended instruction set, which consists of these instructions: ASHC, ASH, DIV, MARK, MUL, RTT, SOB SXT, and XOR.

-mfis | -mkev11

-mno-fis | -mno-kev11

Enable (or diasble) the use of the KEV11 floating-point instructions: FADD, FDIV, FMUL, and FSUB.

-mfpp | -mfpu | -mfp-11

-mno-fpp | -mno-fpu | -mno-fp-11

Enable (or disable) the use of FP-11 floating-point instructions: ABSF, ADDF, CFCC, CLRF, CMPF, DIVF, LDCFF, LDCIF, LDEXP, LDF, LDFPS, MODF, MULF, NEGF, SETD, SETF, SETI, SETL, STCFF, STCFI, STEXP, STF, STFPS, STST, SUBF, and TSTF.

-mlimited-eis | -mno-limited-eis

Enable (or disable) the use of the limited extended instruction set: MARK, RTT, SOB, SXT, and XOR.

The -mno-limited-eis options also implies -mno-eis.

-mmfpt | -mno-mfpt

Enable (or disable) the use of the MFPT instruction.

-mmultiproc | -mno-multiproc

Enable (or disable) the use of multiprocessor instructions: TSTSET and WRTLCK.

-mmxps | -mno-mxps

Enable (or disable) the use of the MFPS and MTPS instructions.

-mspl | -mno-spl

Enable (or disable) the use of the SPL instruction.

Enable (or disable) the use of the microcode instructions: LDUB, MED, and XFC.