These options are defined for the PDP-11:
-mfpu
¶Use hardware FPP floating point. This is the default. (FIS floating point on the PDP-11/40 is not supported.)
-msoft-float
¶Do not use hardware floating point.
-mac0
¶Return floating-point results in ac0 (fr0 in Unix assembler syntax).
-mno-ac0
¶Return floating-point results in memory. This is the default.
-m40
¶Generate code for a PDP-11/40.
-m45
¶Generate code for a PDP-11/45. This is the default.
-m10
¶Generate code for a PDP-11/10.
-mbcopy-builtin
¶Use inline movmemhi
patterns for copying memory. This is the
default.
-mbcopy
¶Do not use inline movmemhi
patterns for copying memory.
-mint16
¶-mno-int32
Use 16-bit int
. This is the default.
-mint32
¶-mno-int16
Use 32-bit int
.
-mfloat64
¶-mno-float32
Use 64-bit float
. This is the default.
-mfloat32
¶-mno-float64
Use 32-bit float
.
-mabshi
¶Use abshi2
pattern. This is the default.
-mno-abshi
¶Do not use abshi2
pattern.
-mbranch-expensive
¶Pretend that branches are expensive. This is for experimenting with code generation only.
-mbranch-cheap
¶Do not pretend that branches are expensive. This is the default.
-munix-asm
¶Use Unix assembler syntax. This is the default when configured for ‘pdp11-*-bsd’.
-mdec-asm
¶Use DEC assembler syntax. This is the default when configured for any PDP-11 target other than ‘pdp11-*-bsd’.