| 1 | @c Copyright (C) 2012-2016 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 XGATE-Dependent |
| 7 | @chapter XGATE Dependent Features |
| 8 | @end ifset |
| 9 | @ifclear GENERIC |
| 10 | @node Machine Dependencies |
| 11 | @chapter XGATE Dependent Features |
| 12 | @end ifclear |
| 13 | |
| 14 | @cindex XGATE support |
| 15 | @menu |
| 16 | * XGATE-Opts:: XGATE Options |
| 17 | * XGATE-Syntax:: Syntax |
| 18 | * XGATE-Directives:: Assembler Directives |
| 19 | * XGATE-Float:: Floating Point |
| 20 | * XGATE-opcodes:: Opcodes |
| 21 | @end menu |
| 22 | |
| 23 | @node XGATE-Opts |
| 24 | @section XGATE Options |
| 25 | |
| 26 | @cindex options, XGATE |
| 27 | @cindex XGATE options |
| 28 | The Freescale XGATE version of @code{@value{AS}} has a few machine |
| 29 | dependent options. |
| 30 | |
| 31 | @table @code |
| 32 | |
| 33 | @cindex @samp{-mshort} |
| 34 | @item -mshort |
| 35 | This option controls the ABI and indicates to use a 16-bit integer ABI. |
| 36 | It has no effect on the assembled instructions. |
| 37 | This is the default. |
| 38 | |
| 39 | @cindex @samp{-mlong} |
| 40 | @item -mlong |
| 41 | This option controls the ABI and indicates to use a 32-bit integer ABI. |
| 42 | |
| 43 | @cindex @samp{-mshort-double} |
| 44 | @item -mshort-double |
| 45 | This option controls the ABI and indicates to use a 32-bit float ABI. |
| 46 | This is the default. |
| 47 | |
| 48 | @cindex @samp{-mlong-double} |
| 49 | @item -mlong-double |
| 50 | This option controls the ABI and indicates to use a 64-bit float ABI. |
| 51 | |
| 52 | @cindex @samp{--print-insn-syntax} |
| 53 | @item --print-insn-syntax |
| 54 | You can use the @samp{--print-insn-syntax} option to obtain the |
| 55 | syntax description of the instruction when an error is detected. |
| 56 | |
| 57 | @cindex @samp{--print-opcodes} |
| 58 | @item --print-opcodes |
| 59 | The @samp{--print-opcodes} option prints the list of all the |
| 60 | instructions with their syntax. Once the list is printed |
| 61 | @code{@value{AS}} exits. |
| 62 | |
| 63 | @end table |
| 64 | |
| 65 | @node XGATE-Syntax |
| 66 | @section Syntax |
| 67 | |
| 68 | @cindex XGATE syntax |
| 69 | @cindex syntax, XGATE |
| 70 | |
| 71 | In XGATE RISC syntax, the instruction name comes first and it may |
| 72 | be followed by up to three operands. Operands are separated by commas |
| 73 | (@samp{,}). @code{@value{AS}} will complain if too many operands are specified |
| 74 | for a given instruction. The same will happen if you specified too few |
| 75 | operands. |
| 76 | |
| 77 | @smallexample |
| 78 | nop |
| 79 | ldl #23 |
| 80 | CMP R1, R2 |
| 81 | @end smallexample |
| 82 | |
| 83 | @cindex line comment character, XGATE |
| 84 | @cindex XGATE line comment character |
| 85 | The presence of a @samp{;} character or a @samp{!} character anywhere |
| 86 | on a line indicates the start of a comment that extends to the end of |
| 87 | that line. |
| 88 | |
| 89 | A @samp{*} or a @samp{#} character at the start of a line also |
| 90 | introduces a line comment, but these characters do not work elsewhere |
| 91 | on the line. If the first character of the line is a @samp{#} then as |
| 92 | well as starting a comment, the line could also be logical line number |
| 93 | directive (@pxref{Comments}) or a preprocessor control command |
| 94 | (@pxref{Preprocessing}). |
| 95 | |
| 96 | @cindex line separator, XGATE |
| 97 | @cindex statement separator, XGATE |
| 98 | @cindex XGATE line separator |
| 99 | The XGATE assembler does not currently support a line separator |
| 100 | character. |
| 101 | |
| 102 | @cindex XGATE addressing modes |
| 103 | @cindex addressing modes, XGATE |
| 104 | The following addressing modes are understood for XGATE: |
| 105 | @table @dfn |
| 106 | @item Inherent |
| 107 | @samp{} |
| 108 | |
| 109 | @item Immediate 3 Bit Wide |
| 110 | @samp{#@var{number}} |
| 111 | |
| 112 | @item Immediate 4 Bit Wide |
| 113 | @samp{#@var{number}} |
| 114 | |
| 115 | @item Immediate 8 Bit Wide |
| 116 | @samp{#@var{number}} |
| 117 | |
| 118 | @item Monadic Addressing |
| 119 | @samp{@var{reg}} |
| 120 | |
| 121 | @item Dyadic Addressing |
| 122 | @samp{@var{reg}, @var{reg}} |
| 123 | |
| 124 | @item Triadic Addressing |
| 125 | @samp{@var{reg}, @var{reg}, @var{reg}} |
| 126 | |
| 127 | @item Relative Addressing 9 Bit Wide |
| 128 | @samp{*@var{symbol}} |
| 129 | |
| 130 | @item Relative Addressing 10 Bit Wide |
| 131 | @samp{*@var{symbol}} |
| 132 | |
| 133 | @item Index Register plus Immediate Offset |
| 134 | @samp{@var{reg}, (@var{reg}, #@var{number})} |
| 135 | |
| 136 | @item Index Register plus Register Offset |
| 137 | @samp{@var{reg}, @var{reg}, @var{reg}} |
| 138 | |
| 139 | @item Index Register plus Register Offset with Post-increment |
| 140 | @samp{@var{reg}, @var{reg}, @var{reg}+} |
| 141 | |
| 142 | @item Index Register plus Register Offset with Pre-decrement |
| 143 | @samp{@var{reg}, @var{reg}, -@var{reg}} |
| 144 | |
| 145 | The register can be either @samp{R0}, @samp{R1}, @samp{R2}, @samp{R3}, |
| 146 | @samp{R4}, @samp{R5}, @samp{R6} or @samp{R7}. |
| 147 | |
| 148 | @end table |
| 149 | |
| 150 | Convience macro opcodes to deal with 16-bit values have been added. |
| 151 | |
| 152 | @table @dfn |
| 153 | |
| 154 | @item Immediate 16 Bit Wide |
| 155 | @samp{#@var{number}}, or @samp{*@var{symbol}} |
| 156 | |
| 157 | For example: |
| 158 | |
| 159 | @smallexample |
| 160 | ldw R1, #1024 |
| 161 | ldw R3, timer |
| 162 | ldw R1, (R1, #0) |
| 163 | COM R1 |
| 164 | stw R2, (R1, #0) |
| 165 | @end smallexample |
| 166 | @end table |
| 167 | |
| 168 | @node XGATE-Directives |
| 169 | @section Assembler Directives |
| 170 | |
| 171 | @cindex assembler directives, XGATE |
| 172 | @cindex XGATE assembler directives |
| 173 | |
| 174 | The XGATE version of @code{@value{AS}} have the following |
| 175 | specific assembler directives: |
| 176 | |
| 177 | @node XGATE-Float |
| 178 | @section Floating Point |
| 179 | |
| 180 | @cindex floating point, XGATE |
| 181 | @cindex XGATE floating point |
| 182 | Packed decimal (P) format floating literals are not supported(yet). |
| 183 | |
| 184 | The floating point formats generated by directives are these. |
| 185 | |
| 186 | @table @code |
| 187 | @cindex @code{float} directive, XGATE |
| 188 | @item .float |
| 189 | @code{Single} precision floating point constants. |
| 190 | |
| 191 | @cindex @code{double} directive, XGATE |
| 192 | @item .double |
| 193 | @code{Double} precision floating point constants. |
| 194 | |
| 195 | @cindex @code{extend} directive XGATE |
| 196 | @cindex @code{ldouble} directive XGATE |
| 197 | @item .extend |
| 198 | @itemx .ldouble |
| 199 | @code{Extended} precision (@code{long double}) floating point constants. |
| 200 | @end table |
| 201 | |
| 202 | @need 2000 |
| 203 | @node XGATE-opcodes |
| 204 | @section Opcodes |
| 205 | |
| 206 | @cindex XGATE opcodes |
| 207 | @cindex instruction set, XGATE |
| 208 | |