gcc/doc/gcc/gcc-command-options/machine-dependent-options/pdp-11-options.rst

   1 ..
   2   Copyright 1988-2022 Free Software Foundation, Inc.
   3   This is part of the GCC manual.
   4   For copying conditions, see the copyright.rst file.
   5
   6 .. program:: PDP-11
   7
   8 .. index:: PDP-11 Options
   9
  10 .. _pdp-11-options:
  11
  12 PDP-11 Options
  13 ^^^^^^^^^^^^^^
  14
  15 These options are defined for the PDP-11:
  16
  17 .. option:: -mfpu
  18
  19   Use hardware FPP floating point.  This is the default.  (FIS floating
  20   point on the PDP-11/40 is not supported.)  Implies :option:`-m45`.
  21
  22 .. option:: -msoft-float
  23
  24   Do not use hardware floating point.
  25
  26 .. option:: -mac0
  27
  28   Return floating-point results in ac0 (fr0 in Unix assembler syntax).
  29
  30 .. option:: -mno-ac0
  31
  32   Return floating-point results in memory.  This is the default.
  33
  34 .. option:: -m40
  35
  36   Generate code for a PDP-11/40.  Implies -msoft-float -mno-split.
  37
  38 .. option:: -m45
  39
  40   Generate code for a PDP-11/45.  This is the default.
  41
  42 .. option:: -m10
  43
  44   Generate code for a PDP-11/10.  Implies -msoft-float -mno-split.
  45
  46 .. option:: -mint16, -mno-int32
  47
  48   Use 16-bit ``int``.  This is the default.
  49
  50 .. option:: -mint32, -mno-int16
  51
  52   Use 32-bit ``int``.
  53
  54 .. option:: -msplit
  55
  56   Target has split instruction and data space.  Implies -m45.
  57
  58 .. option:: -munix-asm
  59
  60   Use Unix assembler syntax.
  61
  62 .. option:: -mdec-asm
  63
  64   Use DEC assembler syntax.
  65
  66 .. option:: -mgnu-asm
  67
  68   Use GNU assembler syntax.  This is the default.
  69
  70 .. option:: -mlra
  71
  72   Use the new LRA register allocator.  By default, the old 'reload'
  73   allocator is used.