123 lines
8 KiB
HTML
123 lines
8 KiB
HTML
<html lang="en">
|
|
<head>
|
|
<title>CRIS-Opts - Using as</title>
|
|
<meta http-equiv="Content-Type" content="text/html">
|
|
<meta name="description" content="Using as">
|
|
<meta name="generator" content="makeinfo 4.7">
|
|
<link title="Top" rel="start" href="index.html#Top">
|
|
<link rel="up" href="CRIS_002dDependent.html#CRIS_002dDependent" title="CRIS-Dependent">
|
|
<link rel="next" href="CRIS_002dExpand.html#CRIS_002dExpand" title="CRIS-Expand">
|
|
<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage">
|
|
<!--
|
|
This file documents the GNU Assembler "as".
|
|
|
|
Copyright (C) 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000, 2001, 2002,
|
|
2006, 2007 Free Software Foundation, Inc.
|
|
|
|
Permission is granted to copy, distribute and/or modify this document
|
|
under the terms of the GNU Free Documentation License, Version 1.1
|
|
or any later version published by the Free Software Foundation;
|
|
with no Invariant Sections, with no Front-Cover Texts, and with no
|
|
Back-Cover Texts. A copy of the license is included in the
|
|
section entitled ``GNU Free Documentation License''.
|
|
|
|
man end-->
|
|
<meta http-equiv="Content-Style-Type" content="text/css">
|
|
<style type="text/css"><!--
|
|
pre.display { font-family:inherit }
|
|
pre.format { font-family:inherit }
|
|
pre.smalldisplay { font-family:inherit; font-size:smaller }
|
|
pre.smallformat { font-family:inherit; font-size:smaller }
|
|
pre.smallexample { font-size:smaller }
|
|
pre.smalllisp { font-size:smaller }
|
|
span.sc { font-variant:small-caps }
|
|
span.roman { font-family: serif; font-weight: normal; }
|
|
--></style>
|
|
</head>
|
|
<body>
|
|
<div class="node">
|
|
<p>
|
|
<a name="CRIS_002dOpts"></a>Next: <a rel="next" accesskey="n" href="CRIS_002dExpand.html#CRIS_002dExpand">CRIS-Expand</a>,
|
|
Up: <a rel="up" accesskey="u" href="CRIS_002dDependent.html#CRIS_002dDependent">CRIS-Dependent</a>
|
|
<hr><br>
|
|
</div>
|
|
|
|
<h4 class="subsection">9.7.1 Command-line Options</h4>
|
|
|
|
<p><a name="index-options_002c-CRIS-669"></a><a name="index-CRIS-options-670"></a>The CRIS version of <code>as</code> has these
|
|
machine-dependent command-line options.
|
|
|
|
<p><a name="index-_0040option_007b_002d_002demulation_003dcriself_007d-command-line-option_002c-CRIS-671"></a><a name="index-_0040option_007b_002d_002demulation_003dcrisaout_007d-command-line-option_002c-CRIS-672"></a><a name="index-CRIS-_0040option_007b_002d_002demulation_003dcriself_007d-command-line-option-673"></a><a name="index-CRIS-_0040option_007b_002d_002demulation_003dcrisaout_007d-command-line-option-674"></a>
|
|
The format of the generated object files can be either ELF or
|
|
a.out, specified by the command-line options
|
|
<span class="option">--emulation=crisaout</span> and <span class="option">--emulation=criself</span>.
|
|
The default is ELF (criself), unless <code>as</code> has been
|
|
configured specifically for a.out by using the configuration
|
|
name <code>cris-axis-aout</code>.
|
|
|
|
<p><a name="index-_0040option_007b_002d_002dunderscore_007d-command-line-option_002c-CRIS-675"></a><a name="index-_0040option_007b_002d_002dno_002dunderscore_007d-command-line-option_002c-CRIS-676"></a><a name="index-CRIS-_0040option_007b_002d_002dunderscore_007d-command-line-option-677"></a><a name="index-CRIS-_0040option_007b_002d_002dno_002dunderscore_007d-command-line-option-678"></a>There are two different link-incompatible ELF object file
|
|
variants for CRIS, for use in environments where symbols are
|
|
expected to be prefixed by a leading <span class="samp">_</span> character and for
|
|
environments without such a symbol prefix. The variant used for
|
|
GNU/Linux port has no symbol prefix. Which variant to produce
|
|
is specified by either of the options <span class="option">--underscore</span> and
|
|
<span class="option">--no-underscore</span>. The default is <span class="option">--underscore</span>.
|
|
Since symbols in CRIS a.out objects are expected to have a
|
|
<span class="samp">_</span> prefix, specifying <span class="option">--no-underscore</span> when
|
|
generating a.out objects is an error. Besides the object format
|
|
difference, the effect of this option is to parse register names
|
|
differently (see <a href="crisnous.html#crisnous">crisnous</a>). The <span class="option">--no-underscore</span>
|
|
option makes a <span class="samp">$</span> register prefix mandatory.
|
|
|
|
<p><a name="index-_0040option_007b_002d_002dpic_007d-command-line-option_002c-CRIS-679"></a><a name="index-CRIS-_0040option_007b_002d_002dpic_007d-command-line-option-680"></a><a name="index-Position_002dindependent-code_002c-CRIS-681"></a><a name="index-CRIS-position_002dindependent-code-682"></a>The option <span class="option">--pic</span> must be passed to <code>as</code> in
|
|
order to recognize the symbol syntax used for ELF (SVR4 PIC)
|
|
position-independent-code (see <a href="crispic.html#crispic">crispic</a>). This will also
|
|
affect expansion of instructions. The expansion with
|
|
<span class="option">--pic</span> will use PC-relative rather than (slightly
|
|
faster) absolute addresses in those expansions.
|
|
|
|
<p><a name="index-_0040option_007b_002d_002dmarch_003d_0040var_007barchitecture_007d_007d-command-line-option_002c-CRIS-683"></a><a name="index-CRIS-_0040option_007b_002d_002dmarch_003d_0040var_007barchitecture_007d_007d-command-line-option-684"></a><a name="index-Architecture-variant-option_002c-CRIS-685"></a><a name="index-CRIS-architecture-variant-option-686"></a>The option <span class="option">--march=</span><var>architecture</var>
|
|
<a name="march_002doption"></a>specifies the recognized instruction set
|
|
and recognized register names. It also controls the
|
|
architecture type of the object file. Valid values for
|
|
<var>architecture</var> are:
|
|
<dl>
|
|
<dt><code>v0_v10</code><dd>All instructions and register names for any architecture variant
|
|
in the set v0<small class="dots">...</small>v10 are recognized. This is the
|
|
default if the target is configured as cris-*.
|
|
|
|
<br><dt><code>v10</code><dd>Only instructions and register names for CRIS v10 (as found in
|
|
ETRAX 100 LX) are recognized. This is the default if the target
|
|
is configured as crisv10-*.
|
|
|
|
<br><dt><code>v32</code><dd>Only instructions and register names for CRIS v32 (code name
|
|
Guinness) are recognized. This is the default if the target is
|
|
configured as crisv32-*. This value implies
|
|
<span class="option">--no-mul-bug-abort</span>. (A subsequent
|
|
<span class="option">--mul-bug-abort</span> will turn it back on.)
|
|
|
|
<br><dt><code>common_v10_v32</code><dd>Only instructions with register names and addressing modes with
|
|
opcodes common to the v10 and v32 are recognized.
|
|
</dl>
|
|
|
|
<p><a name="index-_0040option_007b_002dN_007d-command-line-option_002c-CRIS-687"></a><a name="index-CRIS-_0040option_007b_002dN_007d-command-line-option-688"></a>When <span class="option">-N</span> is specified, <code>as</code> will emit a
|
|
warning when a 16-bit branch instruction is expanded into a
|
|
32-bit multiple-instruction construct (see <a href="CRIS_002dExpand.html#CRIS_002dExpand">CRIS-Expand</a>).
|
|
|
|
<p><a name="index-_0040option_007b_002d_002dno_002dmul_002dbug_002dabort_007d-command-line-option_002c-CRIS-689"></a><a name="index-_0040option_007b_002d_002dmul_002dbug_002dabort_007d-command-line-option_002c-CRIS-690"></a><a name="index-CRIS-_0040option_007b_002d_002dno_002dmul_002dbug_002dabort_007d-command-line-option-691"></a><a name="index-CRIS-_0040option_007b_002d_002dmul_002dbug_002dabort_007d-command-line-option-692"></a>
|
|
Some versions of the CRIS v10, for example in the Etrax 100 LX,
|
|
contain a bug that causes destabilizing memory accesses when a
|
|
multiply instruction is executed with certain values in the
|
|
first operand just before a cache-miss. When the
|
|
<span class="option">--mul-bug-abort</span> command line option is active (the
|
|
default value), <code>as</code> will refuse to assemble a file
|
|
containing a multiply instruction at a dangerous offset, one
|
|
that could be the last on a cache-line, or is in a section with
|
|
insufficient alignment. This placement checking does not catch
|
|
any case where the multiply instruction is dangerously placed
|
|
because it is located in a delay-slot. The
|
|
<span class="option">--mul-bug-abort</span> command line option turns off the
|
|
checking.
|
|
|
|
</body></html>
|
|
|