gcc/doc/gcc/gcc-command-options/machine-dependent-options/c-sky-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:: C-SKY
   7
   8 .. index:: C-SKY Options
   9
  10 .. _c-sky-options:
  11
  12 C-SKY Options
  13 ^^^^^^^^^^^^^
  14
  15 GCC supports these options when compiling for C-SKY V2 processors.
  16
  17 .. option:: -march={arch}
  18
  19   Specify the C-SKY target architecture.  Valid values for :samp:`{arch}` are:
  20   :samp:`ck801`, :samp:`ck802`, :samp:`ck803`, :samp:`ck807`, and :samp:`ck810`.
  21   The default is :samp:`ck810`.
  22
  23 .. option:: -mcpu={cpu}
  24
  25   Specify the C-SKY target processor.  Valid values for :samp:`{cpu}` are:
  26   :samp:`ck801`, :samp:`ck801t`,
  27   :samp:`ck802`, :samp:`ck802t`, :samp:`ck802j`,
  28   :samp:`ck803`, :samp:`ck803h`, :samp:`ck803t`, :samp:`ck803ht`,
  29   :samp:`ck803f`, :samp:`ck803fh`, :samp:`ck803e`, :samp:`ck803eh`,
  30   :samp:`ck803et`, :samp:`ck803eht`, :samp:`ck803ef`, :samp:`ck803efh`,
  31   :samp:`ck803ft`, :samp:`ck803eft`, :samp:`ck803efht`, :samp:`ck803r1`,
  32   :samp:`ck803hr1`, :samp:`ck803tr1`, :samp:`ck803htr1`, :samp:`ck803fr1`,
  33   :samp:`ck803fhr1`, :samp:`ck803er1`, :samp:`ck803ehr1`, :samp:`ck803etr1`,
  34   :samp:`ck803ehtr1`, :samp:`ck803efr1`, :samp:`ck803efhr1`, :samp:`ck803ftr1`,
  35   :samp:`ck803eftr1`, :samp:`ck803efhtr1`,
  36   :samp:`ck803s`, :samp:`ck803st`, :samp:`ck803se`, :samp:`ck803sf`,
  37   :samp:`ck803sef`, :samp:`ck803seft`,
  38   :samp:`ck807e`, :samp:`ck807ef`, :samp:`ck807`, :samp:`ck807f`,
  39   :samp:`ck810e`, :samp:`ck810et`, :samp:`ck810ef`, :samp:`ck810eft`,
  40   :samp:`ck810`, :samp:`ck810v`, :samp:`ck810f`, :samp:`ck810t`, :samp:`ck810fv`,
  41   :samp:`ck810tv`, :samp:`ck810ft`, and :samp:`ck810ftv`.
  42
  43 .. option:: -mbig-endian, -EB, -mlittle-endian, -EL
  44
  45   Select big- or little-endian code.  The default is little-endian.
  46
  47 .. option:: -mfloat-abi={name}
  48
  49   Specifies which floating-point ABI to use.  Permissible values
  50   are: :samp:`soft`, :samp:`softfp` and :samp:`hard`.
  51
  52   Specifying :samp:`soft` causes GCC to generate output containing
  53   library calls for floating-point operations.
  54   :samp:`softfp` allows the generation of code using hardware floating-point
  55   instructions, but still uses the soft-float calling conventions.
  56   :samp:`hard` allows generation of floating-point instructions
  57   and uses FPU-specific calling conventions.
  58
  59   The default depends on the specific target configuration.  Note that
  60   the hard-float and soft-float ABIs are not link-compatible; you must
  61   compile your entire program with the same ABI, and link with a
  62   compatible set of libraries.
  63
  64 .. option:: -mhard-float, -msoft-float
  65
  66   Select hardware or software floating-point implementations.
  67   The default is soft float.
  68
  69 .. option:: -mdouble-float, -mno-double-float
  70
  71   When :option:`-mhard-float` is in effect, enable generation of
  72   double-precision float instructions.  This is the default except
  73   when compiling for CK803.
  74
  75 .. option:: -mfdivdu, -mno-fdivdu
  76
  77   When :option:`-mhard-float` is in effect, enable generation of
  78   ``frecipd``, ``fsqrtd``, and ``fdivd`` instructions.
  79   This is the default except when compiling for CK803.
  80
  81 .. option:: -mfpu={fpu}
  82
  83   Select the floating-point processor.  This option can only be used with
  84   :option:`-mhard-float`.
  85   Values for :samp:`{fpu}` are
  86   :samp:`fpv2_sf` (equivalent to :samp:`-mno-double-float -mno-fdivdu`),
  87   :samp:`fpv2` (:samp:`-mdouble-float -mno-divdu`), and
  88   :samp:`fpv2_divd` (:samp:`-mdouble-float -mdivdu`).
  89
  90 .. option:: -melrw, -mno-elrw
  91
  92   Enable the extended ``lrw`` instruction.  This option defaults to on
  93   for CK801 and off otherwise.
  94
  95 .. option:: -mistack, -mno-istack
  96
  97   Enable interrupt stack instructions; the default is off.
  98
  99   The :option:`-mistack` option is required to handle the
 100   :c-sky-fn-attr:`interrupt` and :c-sky-fn-attr:`isr` function attributes
 101   (see :ref:`c-sky-function-attributes`).
 102
 103 .. option:: -mmp
 104
 105   Enable multiprocessor instructions; the default is off.
 106
 107 .. option:: -mcp
 108
 109   Enable coprocessor instructions; the default is off.
 110
 111 .. option:: -mcache
 112
 113   Enable coprocessor instructions; the default is off.
 114
 115 .. option:: -msecurity
 116
 117   Enable C-SKY security instructions; the default is off.
 118
 119 .. option:: -mtrust
 120
 121   Enable C-SKY trust instructions; the default is off.
 122
 123 .. option:: -mdsp, -medsp, -mvdsp
 124
 125   Enable C-SKY DSP, Enhanced DSP, or Vector DSP instructions, respectively.
 126   All of these options default to off.
 127
 128 .. option:: -mdiv, -mno-div
 129
 130   Generate divide instructions.  Default is off.
 131
 132 .. option:: -msmart, -mno-smart
 133
 134   Generate code for Smart Mode, using only registers numbered 0-7 to allow
 135   use of 16-bit instructions.  This option is ignored for CK801 where this
 136   is the required behavior, and it defaults to on for CK802.
 137   For other targets, the default is off.
 138
 139 .. option:: -mhigh-registers, -mno-high-registers
 140
 141   Generate code using the high registers numbered 16-31.  This option
 142   is not supported on CK801, CK802, or CK803, and is enabled by default
 143   for other processors.
 144
 145 .. option:: -manchor, -mno-anchor
 146
 147   Generate code using global anchor symbol addresses.
 148
 149 .. option:: -mpushpop, -mno-pushpop
 150
 151   Generate code using ``push`` and ``pop`` instructions.  This option
 152   defaults to on.
 153
 154 .. option:: -mmultiple-stld, -mstm, -mno-multiple-stld, -mno-stm
 155
 156   Generate code using ``stm`` and ``ldm`` instructions.  This option
 157   isn't supported on CK801 but is enabled by default on other processors.
 158
 159 .. option:: -mconstpool, -mno-constpool
 160
 161   Create constant pools in the compiler instead of deferring it to the
 162   assembler.  This option is the default and required for correct code
 163   generation on CK801 and CK802, and is optional on other processors.
 164
 165 .. option:: -mstack-size, -mno-stack-size
 166
 167   Emit ``.stack_size`` directives for each function in the assembly
 168   output.  This option defaults to off.
 169
 170 .. option:: -mstack-size
 171
 172   Default setting; overrides :option:`-mno-stack-size`.
 173
 174 .. option:: -mccrt, -mno-ccrt
 175
 176   Generate code for the C-SKY compiler runtime instead of libgcc.  This
 177   option defaults to off.
 178
 179 .. option:: -mbranch-cost={n}
 180
 181   Set the branch costs to roughly ``n`` instructions.  The default is 1.
 182
 183 .. option:: -msched-prolog, -mno-sched-prolog
 184
 185   Permit scheduling of function prologue and epilogue sequences.  Using
 186   this option can result in code that is not compliant with the C-SKY V2 ABI
 187   prologue requirements and that cannot be debugged or backtraced.
 188   It is disabled by default.
 189
 190 .. option:: -msim
 191
 192   Links the library libsemi.a which is in compatible with simulator. Applicable
 193   to ELF compiler only.