1 @c Copyright (C) 2012-2014 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 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 208 209
