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      1 @c Copyright (C) 2005-2014 Free Software Foundation, Inc.
      2 @c This is part of the GAS manual.
      3 @c For copying conditions, see the file as.texinfo.
      4 @ifset GENERIC
      5 @page
      6 @node M32C-Dependent
      7 @chapter M32C Dependent Features
      8 @end ifset
      9 @ifclear GENERIC
     10 @node Machine Dependencies
     11 @chapter M32C Dependent Features
     12 @end ifclear
     13 
     14 @cindex M32C support
     15 
     16 @code{@value{AS}} can assemble code for several different members of
     17 the Renesas M32C family.  Normally the default is to assemble code for
     18 the M16C microprocessor.  The @code{-m32c} option may be used to
     19 change the default to the M32C microprocessor.
     20 
     21 @menu
     22 * M32C-Opts::                   M32C Options
     23 * M32C-Syntax::                 M32C Syntax
     24 @end menu
     25 
     26 @node M32C-Opts
     27 @section M32C Options
     28 
     29 @cindex options, M32C
     30 @cindex M32C options
     31 
     32 The Renesas M32C version of @code{@value{AS}} has these
     33 machine-dependent options:
     34 
     35 @table @code
     36 @item -m32c
     37 @cindex @samp{-m32c} option, M32C
     38 @cindex architecture options, M32C
     39 @cindex M32C architecture option
     40 Assemble M32C instructions.
     41 
     42 @item -m16c
     43 @cindex @samp{-m16c} option, M16C
     44 @cindex architecture options, M16C
     45 @cindex M16C architecture option
     46 Assemble M16C instructions (default).
     47 
     48 @item -relax
     49 Enable support for link-time relaxations.
     50 
     51 @item -h-tick-hex
     52 Support H'00 style hex constants in addition to 0x00 style.
     53 
     54 
     55 @end table
     56 
     57 @node M32C-Syntax
     58 @section M32C Syntax
     59 @menu
     60 * M32C-Modifiers::              Symbolic Operand Modifiers
     61 * M32C-Chars::                  Special Characters
     62 @end menu
     63 
     64 @node M32C-Modifiers
     65 @subsection Symbolic Operand Modifiers
     66 
     67 @cindex M32C modifiers
     68 @cindex modifiers, M32C
     69 
     70 The assembler supports several modifiers when using symbol addresses
     71 in M32C instruction operands.  The general syntax is the following:
     72 
     73 @smallexample
     74 %modifier(symbol)
     75 @end smallexample
     76 
     77 @table @code
     78 @cindex symbol modifiers
     79 
     80 @item %dsp8
     81 @itemx %dsp16
     82 
     83 These modifiers override the assembler's assumptions about how big a
     84 symbol's address is.  Normally, when it sees an operand like
     85 @samp{sym[a0]} it assumes @samp{sym} may require the widest
     86 displacement field (16 bits for @samp{-m16c}, 24 bits for
     87 @samp{-m32c}).  These modifiers tell it to assume the address will fit
     88 in an 8 or 16 bit (respectively) unsigned displacement.  Note that, of
     89 course, if it doesn't actually fit you will get linker errors.  Example:
     90 
     91 @smallexample
     92 mov.w %dsp8(sym)[a0],r1
     93 mov.b #0,%dsp8(sym)[a0]
     94 @end smallexample
     95 
     96 @item %hi8
     97 
     98 This modifier allows you to load bits 16 through 23 of a 24 bit
     99 address into an 8 bit register.  This is useful with, for example, the
    100 M16C @samp{smovf} instruction, which expects a 20 bit address in
    101 @samp{r1h} and @samp{a0}.  Example:
    102 
    103 @smallexample
    104 mov.b #%hi8(sym),r1h
    105 mov.w #%lo16(sym),a0
    106 smovf.b
    107 @end smallexample
    108 
    109 @item %lo16
    110 
    111 Likewise, this modifier allows you to load bits 0 through 15 of a 24
    112 bit address into a 16 bit register.
    113 
    114 @item %hi16
    115 
    116 This modifier allows you to load bits 16 through 31 of a 32 bit
    117 address into a 16 bit register.  While the M32C family only has 24
    118 bits of address space, it does support addresses in pairs of 16 bit
    119 registers (like @samp{a1a0} for the @samp{lde} instruction).  This
    120 modifier is for loading the upper half in such cases.  Example:
    121 
    122 @smallexample
    123 mov.w #%hi16(sym),a1
    124 mov.w #%lo16(sym),a0
    125 @dots{}
    126 lde.w [a1a0],r1
    127 @end smallexample
    128 
    129 @end table
    130 
    131 @node M32C-Chars
    132 @subsection Special Characters
    133 
    134 @cindex line comment character, M32C
    135 @cindex M32C line comment character
    136 The presence of a @samp{;} character on a line indicates the start of
    137 a comment that extends to the end of that line.
    138 
    139 If a @samp{#} appears as the first character of a line, the whole line
    140 is treated as a comment, but in this case the line can also be a
    141 logical line number directive (@pxref{Comments}) or a
    142 preprocessor control command (@pxref{Preprocessing}).
    143 
    144 @cindex line separator, M32C
    145 @cindex statement separator, M32C
    146 @cindex M32C line separator
    147 The @samp{|} character can be used to separate statements on the same
    148 line.
    149