1 @c Copyright 2010 Free Software Foundation, Inc.
2 @c This is part of the GAS manual.
3 @c For copying conditions, see the file as.texinfo.
7 @chapter TIC6X Dependent Features
10 @node Machine Dependencies
11 @chapter TIC6X Dependent Features
15 @cindex TMS320C6X support
17 * TIC6X Options:: Options
18 * TIC6X Syntax:: Syntax
19 * TIC6X Directives:: Directives
23 @section TIC6X Options
25 @cindex options for TIC6X
29 @cindex @code{-march=} command line option, TIC6X
30 @item -march=@var{arch}
31 Enable (only) instructions from architecture @var{arch}. By default,
32 all instructions are permitted.
34 The following values of @var{arch} are accepted: @code{c62x},
35 @code{c64x}, @code{c64x+}, @code{c67x}, @code{c67x+}, @code{c674x}.
37 @cindex @code{-matomic} command line option, TIC6X
38 @cindex @code{-mno-atomic} command line option, TIC6X
41 Enable or disable the optional C64x+ atomic operation instructions.
42 By default, they are enabled if no @option{-march} option is given, or
43 if an architecture is specified with @option{-march} that implies
44 these instructions are present (currently, there are no such
45 architectures); they are disabled if an architecture is specified with
46 @option{-march} on which the instructions are optional or not
47 present. This option overrides such a default from the architecture,
48 independent of the order in which the @option{-march} or
49 @option{-matomic} or @option{-mno-atomic} options are passed.
51 @cindex @code{-mdsbt} command line option, TIC6X
52 @cindex @code{-mno-dsbt} command line option, TIC6X
55 The @option{-mdsbt} option causes the assembler to generate the
56 @code{Tag_ABI_DSBT} attribute with a value of 1, indicating that the
57 code is using DSBT addressing. The @option{-mno-dsbt} option, the
58 default, causes the tag to have a value of 0, indicating that the code
59 does not use DSBT addressing. The linker will emit a warning if
60 objects of different type (DSBT and non-DSBT) are linked together.
62 @cindex @code{-mpid=} command line option, TIC6X
66 The @option{-mpid=} option causes the assembler to generate the
67 @code{Tag_ABI_PID} attribute with a value indicating the form of data
68 addressing used by the code. @option{-mpid=no}, the default,
69 indicates position-dependent data addressing, @option{-mpid=near}
70 indicates position-independent addressing with GOT accesses using near
71 DP addressing, and @option{-mpid=far} indicates position-independent
72 addressing with GOT accesses using far DP addressing. The linker will
73 emit a warning if objects built with different settings of this option
76 @cindex @code{-mpic} command line option, TIC6X
77 @cindex @code{-mno-pic} command line option, TIC6X
80 The @option{-mpic} option causes the assembler to generate the
81 @code{Tag_ABI_PIC} attribute with a value of 1, indicating that the
82 code is using position-independent code addressing, The
83 @code{-mno-pic} option, the default, causes the tag to have a value of
84 0, indicating position-dependent code addressing. The linker will
85 emit a warning if objects of different type (position-dependent and
86 position-independent) are linked together.
88 @cindex TIC6X big-endian output
89 @cindex TIC6X little-endian output
90 @cindex big-endian output, TIC6X
91 @cindex little-endian output, TIC6X
93 @itemx -mlittle-endian
94 Generate code for the specified endianness. The default is
100 @section TIC6X Syntax
102 @cindex line comment character, TIC6X
103 @cindex TIC6X line comment character
104 The presence of a @samp{;} on a line indicates the start of a comment
105 that extends to the end of the current line. If a @samp{#} or
106 @samp{*} appears as the first character of a line, the whole line is
107 treated as a comment.
109 @cindex line separator, TIC6X
110 @cindex statement separator, TIC6X
111 @cindex TIC6X line separator
112 The @samp{@@} character can be used instead of a newline to separate
115 Instruction, register and functional unit names are case-insensitive.
116 @command{@value{AS}} requires fully-specified functional unit names,
117 such as @samp{.S1}, @samp{.L1X} or @samp{.D1T2}, on all instructions
118 using a functional unit.
120 For some instructions, there may be syntactic ambiguity between
121 register or functional unit names and the names of labels or other
122 symbols. To avoid this, enclose the ambiguous symbol name in
123 parentheses; register and functional unit names may not be enclosed in
126 @node TIC6X Directives
127 @section TIC6X Directives
129 @cindex machine directives, TIC6X
130 @cindex TIC6X machine directives
132 Directives controlling the set of instructions accepted by the
133 assembler have effect for instructions between the directive and any
134 subsequent directive overriding it.
138 @cindex @code{.arch} directive, TIC6X
139 @item .arch @var{arch}
140 This has the same effect as @option{-march=@var{arch}}.
142 @cindex @code{.atomic} directive, TIC6X
143 @cindex @code{.noatomic} directive, TIC6X
146 These have the same effects as @option{-matomic} and
147 @option{-mno-atomic}.
149 @cindex @code{.c6xabi_attribute} directive, TIC6X
150 @item .c6xabi_attribute @var{tag}, @var{value}
151 Set the C6000 EABI build attribute @var{tag} to @var{value}.
153 The @var{tag} is either an attribute number or one of
154 @code{Tag_ISA}, @code{Tag_ABI_wchar_t},
155 @code{Tag_ABI_stack_align_needed},
156 @code{Tag_ABI_stack_align_preserved}, @code{Tag_ABI_DSBT},
157 @code{Tag_ABI_PID}, @code{Tag_ABI_PIC},
158 @code{TAG_ABI_array_object_alignment},
159 @code{TAG_ABI_array_object_align_expected},
160 @code{Tag_ABI_compatibility} and @code{Tag_ABI_conformance}. The
161 @var{value} is either a @code{number}, @code{"string"}, or
162 @code{number, "string"} depending on the tag.
164 @cindex @code{.nocmp} directive, TIC6X
166 Disallow use of C64x+ compact instructions in the current text