<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
|
<html>
|
<!-- Copyright (C) 1988-2016 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 1.3 or
|
any later version published by the Free Software Foundation; with the
|
Invariant Sections being "Funding Free Software", the Front-Cover
|
Texts being (a) (see below), and with the Back-Cover Texts being (b)
|
(see below). A copy of the license is included in the section entitled
|
"GNU Free Documentation License".
|
|
(a) The FSF's Front-Cover Text is:
|
|
A GNU Manual
|
|
(b) The FSF's Back-Cover Text is:
|
|
You have freedom to copy and modify this GNU Manual, like GNU
|
software. Copies published by the Free Software Foundation raise
|
funds for GNU development. -->
|
<!-- Created by GNU Texinfo 5.2, http://www.gnu.org/software/texinfo/ -->
|
<head>
|
<title>Using the GNU Compiler Collection (GCC): ARC Options</title>
|
|
<meta name="description" content="Using the GNU Compiler Collection (GCC): ARC Options">
|
<meta name="keywords" content="Using the GNU Compiler Collection (GCC): ARC Options">
|
<meta name="resource-type" content="document">
|
<meta name="distribution" content="global">
|
<meta name="Generator" content="makeinfo">
|
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
|
<link href="index.html#Top" rel="start" title="Top">
|
<link href="Option-Index.html#Option-Index" rel="index" title="Option Index">
|
<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents">
|
<link href="Submodel-Options.html#Submodel-Options" rel="up" title="Submodel Options">
|
<link href="ARM-Options.html#ARM-Options" rel="next" title="ARM Options">
|
<link href="Adapteva-Epiphany-Options.html#Adapteva-Epiphany-Options" rel="prev" title="Adapteva Epiphany Options">
|
<style type="text/css">
|
<!--
|
a.summary-letter {text-decoration: none}
|
blockquote.smallquotation {font-size: smaller}
|
div.display {margin-left: 3.2em}
|
div.example {margin-left: 3.2em}
|
div.indentedblock {margin-left: 3.2em}
|
div.lisp {margin-left: 3.2em}
|
div.smalldisplay {margin-left: 3.2em}
|
div.smallexample {margin-left: 3.2em}
|
div.smallindentedblock {margin-left: 3.2em; font-size: smaller}
|
div.smalllisp {margin-left: 3.2em}
|
kbd {font-style:oblique}
|
pre.display {font-family: inherit}
|
pre.format {font-family: inherit}
|
pre.menu-comment {font-family: serif}
|
pre.menu-preformatted {font-family: serif}
|
pre.smalldisplay {font-family: inherit; font-size: smaller}
|
pre.smallexample {font-size: smaller}
|
pre.smallformat {font-family: inherit; font-size: smaller}
|
pre.smalllisp {font-size: smaller}
|
span.nocodebreak {white-space:nowrap}
|
span.nolinebreak {white-space:nowrap}
|
span.roman {font-family:serif; font-weight:normal}
|
span.sansserif {font-family:sans-serif; font-weight:normal}
|
ul.no-bullet {list-style: none}
|
-->
|
</style>
|
|
|
</head>
|
|
<body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000">
|
<a name="ARC-Options"></a>
|
<div class="header">
|
<p>
|
Next: <a href="ARM-Options.html#ARM-Options" accesskey="n" rel="next">ARM Options</a>, Previous: <a href="Adapteva-Epiphany-Options.html#Adapteva-Epiphany-Options" accesskey="p" rel="prev">Adapteva Epiphany Options</a>, Up: <a href="Submodel-Options.html#Submodel-Options" accesskey="u" rel="up">Submodel Options</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p>
|
</div>
|
<hr>
|
<a name="ARC-Options-1"></a>
|
<h4 class="subsection">3.18.3 ARC Options</h4>
|
<a name="index-ARC-options"></a>
|
|
<p>The following options control the architecture variant for which code
|
is being compiled:
|
</p>
|
<dl compact="compact">
|
<dt><code>-mbarrel-shifter</code></dt>
|
<dd><a name="index-mbarrel_002dshifter"></a>
|
<p>Generate instructions supported by barrel shifter. This is the default
|
unless <samp>-mcpu=ARC601</samp> or ‘<samp>-mcpu=ARCEM</samp>’ is in effect.
|
</p>
|
</dd>
|
<dt><code>-mcpu=<var>cpu</var></code></dt>
|
<dd><a name="index-mcpu-1"></a>
|
<p>Set architecture type, register usage, and instruction scheduling
|
parameters for <var>cpu</var>. There are also shortcut alias options
|
available for backward compatibility and convenience. Supported
|
values for <var>cpu</var> are
|
</p>
|
<dl compact="compact">
|
<dd><a name="index-mA6"></a>
|
<a name="index-mARC600"></a>
|
</dd>
|
<dt>‘<samp>ARC600</samp>’</dt>
|
<dt>‘<samp>arc600</samp>’</dt>
|
<dd><p>Compile for ARC600. Aliases: <samp>-mA6</samp>, <samp>-mARC600</samp>.
|
</p>
|
</dd>
|
<dt>‘<samp>ARC601</samp>’</dt>
|
<dt>‘<samp>arc601</samp>’</dt>
|
<dd><a name="index-mARC601"></a>
|
<p>Compile for ARC601. Alias: <samp>-mARC601</samp>.
|
</p>
|
</dd>
|
<dt>‘<samp>ARC700</samp>’</dt>
|
<dt>‘<samp>arc700</samp>’</dt>
|
<dd><a name="index-mA7"></a>
|
<a name="index-mARC700"></a>
|
<p>Compile for ARC700. Aliases: <samp>-mA7</samp>, <samp>-mARC700</samp>.
|
This is the default when configured with <samp>--with-cpu=arc700</samp>.
|
</p>
|
</dd>
|
<dt>‘<samp>ARCEM</samp>’</dt>
|
<dt>‘<samp>arcem</samp>’</dt>
|
<dd><p>Compile for ARC EM.
|
</p>
|
</dd>
|
<dt>‘<samp>ARCHS</samp>’</dt>
|
<dt>‘<samp>archs</samp>’</dt>
|
<dd><p>Compile for ARC HS.
|
</p></dd>
|
</dl>
|
|
</dd>
|
<dt><code>-mdpfp</code></dt>
|
<dd><a name="index-mdpfp"></a>
|
</dd>
|
<dt><code>-mdpfp-compact</code></dt>
|
<dd><a name="index-mdpfp_002dcompact"></a>
|
<p>FPX: Generate Double Precision FPX instructions, tuned for the compact
|
implementation.
|
</p>
|
</dd>
|
<dt><code>-mdpfp-fast</code></dt>
|
<dd><a name="index-mdpfp_002dfast"></a>
|
<p>FPX: Generate Double Precision FPX instructions, tuned for the fast
|
implementation.
|
</p>
|
</dd>
|
<dt><code>-mno-dpfp-lrsr</code></dt>
|
<dd><a name="index-mno_002ddpfp_002dlrsr"></a>
|
<p>Disable LR and SR instructions from using FPX extension aux registers.
|
</p>
|
</dd>
|
<dt><code>-mea</code></dt>
|
<dd><a name="index-mea"></a>
|
<p>Generate Extended arithmetic instructions. Currently only
|
<code>divaw</code>, <code>adds</code>, <code>subs</code>, and <code>sat16</code> are
|
supported. This is always enabled for <samp>-mcpu=ARC700</samp>.
|
</p>
|
</dd>
|
<dt><code>-mno-mpy</code></dt>
|
<dd><a name="index-mno_002dmpy"></a>
|
<p>Do not generate mpy instructions for ARC700.
|
</p>
|
</dd>
|
<dt><code>-mmul32x16</code></dt>
|
<dd><a name="index-mmul32x16"></a>
|
<p>Generate 32x16 bit multiply and mac instructions.
|
</p>
|
</dd>
|
<dt><code>-mmul64</code></dt>
|
<dd><a name="index-mmul64"></a>
|
<p>Generate mul64 and mulu64 instructions. Only valid for <samp>-mcpu=ARC600</samp>.
|
</p>
|
</dd>
|
<dt><code>-mnorm</code></dt>
|
<dd><a name="index-mnorm"></a>
|
<p>Generate norm instruction. This is the default if <samp>-mcpu=ARC700</samp>
|
is in effect.
|
</p>
|
</dd>
|
<dt><code>-mspfp</code></dt>
|
<dd><a name="index-mspfp"></a>
|
</dd>
|
<dt><code>-mspfp-compact</code></dt>
|
<dd><a name="index-mspfp_002dcompact"></a>
|
<p>FPX: Generate Single Precision FPX instructions, tuned for the compact
|
implementation.
|
</p>
|
</dd>
|
<dt><code>-mspfp-fast</code></dt>
|
<dd><a name="index-mspfp_002dfast"></a>
|
<p>FPX: Generate Single Precision FPX instructions, tuned for the fast
|
implementation.
|
</p>
|
</dd>
|
<dt><code>-msimd</code></dt>
|
<dd><a name="index-msimd"></a>
|
<p>Enable generation of ARC SIMD instructions via target-specific
|
builtins. Only valid for <samp>-mcpu=ARC700</samp>.
|
</p>
|
</dd>
|
<dt><code>-msoft-float</code></dt>
|
<dd><a name="index-msoft_002dfloat"></a>
|
<p>This option ignored; it is provided for compatibility purposes only.
|
Software floating point code is emitted by default, and this default
|
can overridden by FPX options; ‘<samp>mspfp</samp>’, ‘<samp>mspfp-compact</samp>’, or
|
‘<samp>mspfp-fast</samp>’ for single precision, and ‘<samp>mdpfp</samp>’,
|
‘<samp>mdpfp-compact</samp>’, or ‘<samp>mdpfp-fast</samp>’ for double precision.
|
</p>
|
</dd>
|
<dt><code>-mswap</code></dt>
|
<dd><a name="index-mswap"></a>
|
<p>Generate swap instructions.
|
</p>
|
</dd>
|
<dt><code>-matomic</code></dt>
|
<dd><a name="index-matomic"></a>
|
<p>This enables Locked Load/Store Conditional extension to implement
|
atomic memopry built-in functions. Not available for ARC 6xx or ARC
|
EM cores.
|
</p>
|
</dd>
|
<dt><code>-mdiv-rem</code></dt>
|
<dd><a name="index-mdiv_002drem"></a>
|
<p>Enable DIV/REM instructions for ARCv2 cores.
|
</p>
|
</dd>
|
<dt><code>-mcode-density</code></dt>
|
<dd><a name="index-mcode_002ddensity"></a>
|
<p>Enable code density instructions for ARC EM, default on for ARC HS.
|
</p>
|
</dd>
|
<dt><code>-mll64</code></dt>
|
<dd><a name="index-mll64"></a>
|
<p>Enable double load/store operations for ARC HS cores.
|
</p>
|
</dd>
|
<dt><code>-mmpy-option=<var>multo</var></code></dt>
|
<dd><a name="index-mmpy_002doption"></a>
|
<p>Compile ARCv2 code with a multiplier design option. ‘<samp>wlh1</samp>’ is
|
the default value. The recognized values for <var>multo</var> are:
|
</p>
|
<dl compact="compact">
|
<dt>‘<samp>0</samp>’</dt>
|
<dd><p>No multiplier available.
|
</p>
|
</dd>
|
<dt>‘<samp>1</samp>’</dt>
|
<dd><a name="index-w-2"></a>
|
<p>The multiply option is set to w: 16x16 multiplier, fully pipelined.
|
The following instructions are enabled: MPYW, and MPYUW.
|
</p>
|
</dd>
|
<dt>‘<samp>2</samp>’</dt>
|
<dd><a name="index-wlh1"></a>
|
<p>The multiply option is set to wlh1: 32x32 multiplier, fully
|
pipelined (1 stage). The following instructions are additionally
|
enabled: MPY, MPYU, MPYM, MPYMU, and MPY_S.
|
</p>
|
</dd>
|
<dt>‘<samp>3</samp>’</dt>
|
<dd><a name="index-wlh2"></a>
|
<p>The multiply option is set to wlh2: 32x32 multiplier, fully pipelined
|
(2 stages). The following instructions are additionally enabled: MPY,
|
MPYU, MPYM, MPYMU, and MPY_S.
|
</p>
|
</dd>
|
<dt>‘<samp>4</samp>’</dt>
|
<dd><a name="index-wlh3"></a>
|
<p>The multiply option is set to wlh3: Two 16x16 multiplier, blocking,
|
sequential. The following instructions are additionally enabled: MPY,
|
MPYU, MPYM, MPYMU, and MPY_S.
|
</p>
|
</dd>
|
<dt>‘<samp>5</samp>’</dt>
|
<dd><a name="index-wlh4"></a>
|
<p>The multiply option is set to wlh4: One 16x16 multiplier, blocking,
|
sequential. The following instructions are additionally enabled: MPY,
|
MPYU, MPYM, MPYMU, and MPY_S.
|
</p>
|
</dd>
|
<dt>‘<samp>6</samp>’</dt>
|
<dd><a name="index-wlh5"></a>
|
<p>The multiply option is set to wlh5: One 32x4 multiplier, blocking,
|
sequential. The following instructions are additionally enabled: MPY,
|
MPYU, MPYM, MPYMU, and MPY_S.
|
</p>
|
</dd>
|
</dl>
|
|
<p>This option is only available for ARCv2 cores.
|
</p>
|
</dd>
|
<dt><code>-mfpu=<var>fpu</var></code></dt>
|
<dd><a name="index-mfpu"></a>
|
<p>Enables specific floating-point hardware extension for ARCv2
|
core. Supported values for <var>fpu</var> are:
|
</p>
|
<dl compact="compact">
|
<dt>‘<samp>fpus</samp>’</dt>
|
<dd><a name="index-fpus"></a>
|
<p>Enables support for single precision floating point hardware
|
extensions.
|
</p>
|
</dd>
|
<dt>‘<samp>fpud</samp>’</dt>
|
<dd><a name="index-fpud"></a>
|
<p>Enables support for double precision floating point hardware
|
extensions. The single precision floating point extension is also
|
enabled. Not available for ARC EM.
|
</p>
|
</dd>
|
<dt>‘<samp>fpuda</samp>’</dt>
|
<dd><a name="index-fpuda"></a>
|
<p>Enables support for double precision floating point hardware
|
extensions using double precision assist instructions. The single
|
precision floating point extension is also enabled. This option is
|
only available for ARC EM.
|
</p>
|
</dd>
|
<dt>‘<samp>fpuda_div</samp>’</dt>
|
<dd><a name="index-fpuda_005fdiv"></a>
|
<p>Enables support for double precision floating point hardware
|
extensions using double precision assist instructions, and simple
|
precision square-root and divide hardware extensions. The single
|
precision floating point extension is also enabled. This option is
|
only available for ARC EM.
|
</p>
|
</dd>
|
<dt>‘<samp>fpuda_fma</samp>’</dt>
|
<dd><a name="index-fpuda_005ffma"></a>
|
<p>Enables support for double precision floating point hardware
|
extensions using double precision assist instructions, and simple
|
precision fused multiple and add hardware extension. The single
|
precision floating point extension is also enabled. This option is
|
only available for ARC EM.
|
</p>
|
</dd>
|
<dt>‘<samp>fpuda_all</samp>’</dt>
|
<dd><a name="index-fpuda_005fall"></a>
|
<p>Enables support for double precision floating point hardware
|
extensions using double precision assist instructions, and all simple
|
precision hardware extensions. The single precision floating point
|
extension is also enabled. This option is only available for ARC EM.
|
</p>
|
</dd>
|
<dt>‘<samp>fpus_div</samp>’</dt>
|
<dd><a name="index-fpus_005fdiv"></a>
|
<p>Enables support for single precision floating point, and single
|
precision square-root and divide hardware extensions.
|
</p>
|
</dd>
|
<dt>‘<samp>fpud_div</samp>’</dt>
|
<dd><a name="index-fpud_005fdiv"></a>
|
<p>Enables support for double precision floating point, and double
|
precision square-root and divide hardware extensions. This option
|
includes option ‘<samp>fpus_div</samp>’. Not available for ARC EM.
|
</p>
|
</dd>
|
<dt>‘<samp>fpus_fma</samp>’</dt>
|
<dd><a name="index-fpus_005ffma"></a>
|
<p>Enables support for single precision floating point, and single
|
precision fused multiple and add hardware extensions.
|
</p>
|
</dd>
|
<dt>‘<samp>fpud_fma</samp>’</dt>
|
<dd><a name="index-fpud_005ffma"></a>
|
<p>Enables support for double precision floating point, and double
|
precision fused multiple and add hardware extensions. This option
|
includes option ‘<samp>fpus_fma</samp>’. Not available for ARC EM.
|
</p>
|
</dd>
|
<dt>‘<samp>fpus_all</samp>’</dt>
|
<dd><a name="index-fpus_005fall"></a>
|
<p>Enables support for all single precision floating point hardware
|
extensions.
|
</p>
|
</dd>
|
<dt>‘<samp>fpud_all</samp>’</dt>
|
<dd><a name="index-fpud_005fall"></a>
|
<p>Enables support for all single and double precision floating point
|
hardware extensions. Not available for ARC EM.
|
</p>
|
</dd>
|
</dl>
|
|
</dd>
|
</dl>
|
|
<p>The following options are passed through to the assembler, and also
|
define preprocessor macro symbols.
|
</p>
|
<dl compact="compact">
|
<dt><code>-mdsp-packa</code></dt>
|
<dd><a name="index-mdsp_002dpacka"></a>
|
<p>Passed down to the assembler to enable the DSP Pack A extensions.
|
Also sets the preprocessor symbol <code>__Xdsp_packa</code>.
|
</p>
|
</dd>
|
<dt><code>-mdvbf</code></dt>
|
<dd><a name="index-mdvbf"></a>
|
<p>Passed down to the assembler to enable the dual viterbi butterfly
|
extension. Also sets the preprocessor symbol <code>__Xdvbf</code>.
|
</p>
|
</dd>
|
<dt><code>-mlock</code></dt>
|
<dd><a name="index-mlock"></a>
|
<p>Passed down to the assembler to enable the Locked Load/Store
|
Conditional extension. Also sets the preprocessor symbol
|
<code>__Xlock</code>.
|
</p>
|
</dd>
|
<dt><code>-mmac-d16</code></dt>
|
<dd><a name="index-mmac_002dd16"></a>
|
<p>Passed down to the assembler. Also sets the preprocessor symbol
|
<code>__Xxmac_d16</code>.
|
</p>
|
</dd>
|
<dt><code>-mmac-24</code></dt>
|
<dd><a name="index-mmac_002d24"></a>
|
<p>Passed down to the assembler. Also sets the preprocessor symbol
|
<code>__Xxmac_24</code>.
|
</p>
|
</dd>
|
<dt><code>-mrtsc</code></dt>
|
<dd><a name="index-mrtsc"></a>
|
<p>Passed down to the assembler to enable the 64-bit Time-Stamp Counter
|
extension instruction. Also sets the preprocessor symbol
|
<code>__Xrtsc</code>.
|
</p>
|
</dd>
|
<dt><code>-mswape</code></dt>
|
<dd><a name="index-mswape"></a>
|
<p>Passed down to the assembler to enable the swap byte ordering
|
extension instruction. Also sets the preprocessor symbol
|
<code>__Xswape</code>.
|
</p>
|
</dd>
|
<dt><code>-mtelephony</code></dt>
|
<dd><a name="index-mtelephony"></a>
|
<p>Passed down to the assembler to enable dual and single operand
|
instructions for telephony. Also sets the preprocessor symbol
|
<code>__Xtelephony</code>.
|
</p>
|
</dd>
|
<dt><code>-mxy</code></dt>
|
<dd><a name="index-mxy"></a>
|
<p>Passed down to the assembler to enable the XY Memory extension. Also
|
sets the preprocessor symbol <code>__Xxy</code>.
|
</p>
|
</dd>
|
</dl>
|
|
<p>The following options control how the assembly code is annotated:
|
</p>
|
<dl compact="compact">
|
<dt><code>-misize</code></dt>
|
<dd><a name="index-misize"></a>
|
<p>Annotate assembler instructions with estimated addresses.
|
</p>
|
</dd>
|
<dt><code>-mannotate-align</code></dt>
|
<dd><a name="index-mannotate_002dalign"></a>
|
<p>Explain what alignment considerations lead to the decision to make an
|
instruction short or long.
|
</p>
|
</dd>
|
</dl>
|
|
<p>The following options are passed through to the linker:
|
</p>
|
<dl compact="compact">
|
<dt><code>-marclinux</code></dt>
|
<dd><a name="index-marclinux"></a>
|
<p>Passed through to the linker, to specify use of the <code>arclinux</code> emulation.
|
This option is enabled by default in tool chains built for
|
<code><span class="nolinebreak">arc-linux-uclibc</span></code><!-- /@w --> and <code><span class="nolinebreak">arceb-linux-uclibc</span></code><!-- /@w --> targets
|
when profiling is not requested.
|
</p>
|
</dd>
|
<dt><code>-marclinux_prof</code></dt>
|
<dd><a name="index-marclinux_005fprof"></a>
|
<p>Passed through to the linker, to specify use of the
|
<code>arclinux_prof</code> emulation. This option is enabled by default in
|
tool chains built for <code><span class="nolinebreak">arc-linux-uclibc</span></code><!-- /@w --> and
|
<code><span class="nolinebreak">arceb-linux-uclibc</span></code><!-- /@w --> targets when profiling is requested.
|
</p>
|
</dd>
|
</dl>
|
|
<p>The following options control the semantics of generated code:
|
</p>
|
<dl compact="compact">
|
<dt><code>-mlong-calls</code></dt>
|
<dd><a name="index-mlong_002dcalls-1"></a>
|
<p>Generate call insns as register indirect calls, thus providing access
|
to the full 32-bit address range.
|
</p>
|
</dd>
|
<dt><code>-mmedium-calls</code></dt>
|
<dd><a name="index-mmedium_002dcalls"></a>
|
<p>Don’t use less than 25 bit addressing range for calls, which is the
|
offset available for an unconditional branch-and-link
|
instruction. Conditional execution of function calls is suppressed, to
|
allow use of the 25-bit range, rather than the 21-bit range with
|
conditional branch-and-link. This is the default for tool chains built
|
for <code><span class="nolinebreak">arc-linux-uclibc</span></code><!-- /@w --> and <code><span class="nolinebreak">arceb-linux-uclibc</span></code><!-- /@w --> targets.
|
</p>
|
</dd>
|
<dt><code>-mno-sdata</code></dt>
|
<dd><a name="index-mno_002dsdata"></a>
|
<p>Do not generate sdata references. This is the default for tool chains
|
built for <code><span class="nolinebreak">arc-linux-uclibc</span></code><!-- /@w --> and <code><span class="nolinebreak">arceb-linux-uclibc</span></code><!-- /@w -->
|
targets.
|
</p>
|
</dd>
|
<dt><code>-mucb-mcount</code></dt>
|
<dd><a name="index-mucb_002dmcount"></a>
|
<p>Instrument with mcount calls as used in UCB code. I.e. do the
|
counting in the callee, not the caller. By default ARC instrumentation
|
counts in the caller.
|
</p>
|
</dd>
|
<dt><code>-mvolatile-cache</code></dt>
|
<dd><a name="index-mvolatile_002dcache"></a>
|
<p>Use ordinarily cached memory accesses for volatile references. This is the
|
default.
|
</p>
|
</dd>
|
<dt><code>-mno-volatile-cache</code></dt>
|
<dd><a name="index-mno_002dvolatile_002dcache"></a>
|
<p>Enable cache bypass for volatile references.
|
</p>
|
</dd>
|
</dl>
|
|
<p>The following options fine tune code generation:
|
</p><dl compact="compact">
|
<dt><code>-malign-call</code></dt>
|
<dd><a name="index-malign_002dcall"></a>
|
<p>Do alignment optimizations for call instructions.
|
</p>
|
</dd>
|
<dt><code>-mauto-modify-reg</code></dt>
|
<dd><a name="index-mauto_002dmodify_002dreg"></a>
|
<p>Enable the use of pre/post modify with register displacement.
|
</p>
|
</dd>
|
<dt><code>-mbbit-peephole</code></dt>
|
<dd><a name="index-mbbit_002dpeephole"></a>
|
<p>Enable bbit peephole2.
|
</p>
|
</dd>
|
<dt><code>-mno-brcc</code></dt>
|
<dd><a name="index-mno_002dbrcc"></a>
|
<p>This option disables a target-specific pass in <samp>arc_reorg</samp> to
|
generate <code>BRcc</code> instructions. It has no effect on <code>BRcc</code>
|
generation driven by the combiner pass.
|
</p>
|
</dd>
|
<dt><code>-mcase-vector-pcrel</code></dt>
|
<dd><a name="index-mcase_002dvector_002dpcrel"></a>
|
<p>Use pc-relative switch case tables - this enables case table shortening.
|
This is the default for <samp>-Os</samp>.
|
</p>
|
</dd>
|
<dt><code>-mcompact-casesi</code></dt>
|
<dd><a name="index-mcompact_002dcasesi"></a>
|
<p>Enable compact casesi pattern.
|
This is the default for <samp>-Os</samp>.
|
</p>
|
</dd>
|
<dt><code>-mno-cond-exec</code></dt>
|
<dd><a name="index-mno_002dcond_002dexec"></a>
|
<p>Disable ARCompact specific pass to generate conditional execution instructions.
|
Due to delay slot scheduling and interactions between operand numbers,
|
literal sizes, instruction lengths, and the support for conditional execution,
|
the target-independent pass to generate conditional execution is often lacking,
|
so the ARC port has kept a special pass around that tries to find more
|
conditional execution generating opportunities after register allocation,
|
branch shortening, and delay slot scheduling have been done. This pass
|
generally, but not always, improves performance and code size, at the cost of
|
extra compilation time, which is why there is an option to switch it off.
|
If you have a problem with call instructions exceeding their allowable
|
offset range because they are conditionalized, you should consider using
|
<samp>-mmedium-calls</samp> instead.
|
</p>
|
</dd>
|
<dt><code>-mearly-cbranchsi</code></dt>
|
<dd><a name="index-mearly_002dcbranchsi"></a>
|
<p>Enable pre-reload use of the cbranchsi pattern.
|
</p>
|
</dd>
|
<dt><code>-mexpand-adddi</code></dt>
|
<dd><a name="index-mexpand_002dadddi"></a>
|
<p>Expand <code>adddi3</code> and <code>subdi3</code> at rtl generation time into
|
<code>add.f</code>, <code>adc</code> etc.
|
</p>
|
</dd>
|
<dt><code>-mindexed-loads</code></dt>
|
<dd><a name="index-mindexed_002dloads"></a>
|
<p>Enable the use of indexed loads. This can be problematic because some
|
optimizers then assume that indexed stores exist, which is not
|
the case.
|
</p>
|
<a name="index-mlra"></a>
|
<p>Enable Local Register Allocation. This is still experimental for ARC,
|
so by default the compiler uses standard reload
|
(i.e. <samp>-mno-lra</samp>).
|
</p>
|
</dd>
|
<dt><code>-mlra-priority-none</code></dt>
|
<dd><a name="index-mlra_002dpriority_002dnone"></a>
|
<p>Don’t indicate any priority for target registers.
|
</p>
|
</dd>
|
<dt><code>-mlra-priority-compact</code></dt>
|
<dd><a name="index-mlra_002dpriority_002dcompact"></a>
|
<p>Indicate target register priority for r0..r3 / r12..r15.
|
</p>
|
</dd>
|
<dt><code>-mlra-priority-noncompact</code></dt>
|
<dd><a name="index-mlra_002dpriority_002dnoncompact"></a>
|
<p>Reduce target register priority for r0..r3 / r12..r15.
|
</p>
|
</dd>
|
<dt><code>-mno-millicode</code></dt>
|
<dd><a name="index-mno_002dmillicode"></a>
|
<p>When optimizing for size (using <samp>-Os</samp>), prologues and epilogues
|
that have to save or restore a large number of registers are often
|
shortened by using call to a special function in libgcc; this is
|
referred to as a <em>millicode</em> call. As these calls can pose
|
performance issues, and/or cause linking issues when linking in a
|
nonstandard way, this option is provided to turn off millicode call
|
generation.
|
</p>
|
</dd>
|
<dt><code>-mmixed-code</code></dt>
|
<dd><a name="index-mmixed_002dcode"></a>
|
<p>Tweak register allocation to help 16-bit instruction generation.
|
This generally has the effect of decreasing the average instruction size
|
while increasing the instruction count.
|
</p>
|
</dd>
|
<dt><code>-mq-class</code></dt>
|
<dd><a name="index-mq_002dclass"></a>
|
<p>Enable ’q’ instruction alternatives.
|
This is the default for <samp>-Os</samp>.
|
</p>
|
</dd>
|
<dt><code>-mRcq</code></dt>
|
<dd><a name="index-mRcq"></a>
|
<p>Enable Rcq constraint handling - most short code generation depends on this.
|
This is the default.
|
</p>
|
</dd>
|
<dt><code>-mRcw</code></dt>
|
<dd><a name="index-mRcw"></a>
|
<p>Enable Rcw constraint handling - ccfsm condexec mostly depends on this.
|
This is the default.
|
</p>
|
</dd>
|
<dt><code>-msize-level=<var>level</var></code></dt>
|
<dd><a name="index-msize_002dlevel"></a>
|
<p>Fine-tune size optimization with regards to instruction lengths and alignment.
|
The recognized values for <var>level</var> are:
|
</p><dl compact="compact">
|
<dt>‘<samp>0</samp>’</dt>
|
<dd><p>No size optimization. This level is deprecated and treated like ‘<samp>1</samp>’.
|
</p>
|
</dd>
|
<dt>‘<samp>1</samp>’</dt>
|
<dd><p>Short instructions are used opportunistically.
|
</p>
|
</dd>
|
<dt>‘<samp>2</samp>’</dt>
|
<dd><p>In addition, alignment of loops and of code after barriers are dropped.
|
</p>
|
</dd>
|
<dt>‘<samp>3</samp>’</dt>
|
<dd><p>In addition, optional data alignment is dropped, and the option <samp>Os</samp> is enabled.
|
</p>
|
</dd>
|
</dl>
|
|
<p>This defaults to ‘<samp>3</samp>’ when <samp>-Os</samp> is in effect. Otherwise,
|
the behavior when this is not set is equivalent to level ‘<samp>1</samp>’.
|
</p>
|
</dd>
|
<dt><code>-mtune=<var>cpu</var></code></dt>
|
<dd><a name="index-mtune-1"></a>
|
<p>Set instruction scheduling parameters for <var>cpu</var>, overriding any implied
|
by <samp>-mcpu=</samp>.
|
</p>
|
<p>Supported values for <var>cpu</var> are
|
</p>
|
<dl compact="compact">
|
<dt>‘<samp>ARC600</samp>’</dt>
|
<dd><p>Tune for ARC600 cpu.
|
</p>
|
</dd>
|
<dt>‘<samp>ARC601</samp>’</dt>
|
<dd><p>Tune for ARC601 cpu.
|
</p>
|
</dd>
|
<dt>‘<samp>ARC700</samp>’</dt>
|
<dd><p>Tune for ARC700 cpu with standard multiplier block.
|
</p>
|
</dd>
|
<dt>‘<samp>ARC700-xmac</samp>’</dt>
|
<dd><p>Tune for ARC700 cpu with XMAC block.
|
</p>
|
</dd>
|
<dt>‘<samp>ARC725D</samp>’</dt>
|
<dd><p>Tune for ARC725D cpu.
|
</p>
|
</dd>
|
<dt>‘<samp>ARC750D</samp>’</dt>
|
<dd><p>Tune for ARC750D cpu.
|
</p>
|
</dd>
|
</dl>
|
|
</dd>
|
<dt><code>-mmultcost=<var>num</var></code></dt>
|
<dd><a name="index-mmultcost"></a>
|
<p>Cost to assume for a multiply instruction, with ‘<samp>4</samp>’ being equal to a
|
normal instruction.
|
</p>
|
</dd>
|
<dt><code>-munalign-prob-threshold=<var>probability</var></code></dt>
|
<dd><a name="index-munalign_002dprob_002dthreshold"></a>
|
<p>Set probability threshold for unaligning branches.
|
When tuning for ‘<samp>ARC700</samp>’ and optimizing for speed, branches without
|
filled delay slot are preferably emitted unaligned and long, unless
|
profiling indicates that the probability for the branch to be taken
|
is below <var>probability</var>. See <a href="Cross_002dprofiling.html#Cross_002dprofiling">Cross-profiling</a>.
|
The default is (REG_BR_PROB_BASE/2), i.e. 5000.
|
</p>
|
</dd>
|
</dl>
|
|
<p>The following options are maintained for backward compatibility, but
|
are now deprecated and will be removed in a future release:
|
</p>
|
<dl compact="compact">
|
<dt><code>-margonaut</code></dt>
|
<dd><a name="index-margonaut"></a>
|
<p>Obsolete FPX.
|
</p>
|
</dd>
|
<dt><code>-mbig-endian</code></dt>
|
<dd><a name="index-mbig_002dendian-1"></a>
|
</dd>
|
<dt><code>-EB</code></dt>
|
<dd><a name="index-EB"></a>
|
<p>Compile code for big endian targets. Use of these options is now
|
deprecated. Users wanting big-endian code, should use the
|
<code><span class="nolinebreak">arceb-elf32</span></code><!-- /@w --> and <code><span class="nolinebreak">arceb-linux-uclibc</span></code><!-- /@w --> targets when
|
building the tool chain, for which big-endian is the default.
|
</p>
|
</dd>
|
<dt><code>-mlittle-endian</code></dt>
|
<dd><a name="index-mlittle_002dendian-1"></a>
|
</dd>
|
<dt><code>-EL</code></dt>
|
<dd><a name="index-EL"></a>
|
<p>Compile code for little endian targets. Use of these options is now
|
deprecated. Users wanting little-endian code should use the
|
<code><span class="nolinebreak">arc-elf32</span></code><!-- /@w --> and <code><span class="nolinebreak">arc-linux-uclibc</span></code><!-- /@w --> targets when
|
building the tool chain, for which little-endian is the default.
|
</p>
|
</dd>
|
<dt><code>-mbarrel_shifter</code></dt>
|
<dd><a name="index-mbarrel_005fshifter"></a>
|
<p>Replaced by <samp>-mbarrel-shifter</samp>.
|
</p>
|
</dd>
|
<dt><code>-mdpfp_compact</code></dt>
|
<dd><a name="index-mdpfp_005fcompact"></a>
|
<p>Replaced by <samp>-mdpfp-compact</samp>.
|
</p>
|
</dd>
|
<dt><code>-mdpfp_fast</code></dt>
|
<dd><a name="index-mdpfp_005ffast"></a>
|
<p>Replaced by <samp>-mdpfp-fast</samp>.
|
</p>
|
</dd>
|
<dt><code>-mdsp_packa</code></dt>
|
<dd><a name="index-mdsp_005fpacka"></a>
|
<p>Replaced by <samp>-mdsp-packa</samp>.
|
</p>
|
</dd>
|
<dt><code>-mEA</code></dt>
|
<dd><a name="index-mEA"></a>
|
<p>Replaced by <samp>-mea</samp>.
|
</p>
|
</dd>
|
<dt><code>-mmac_24</code></dt>
|
<dd><a name="index-mmac_005f24"></a>
|
<p>Replaced by <samp>-mmac-24</samp>.
|
</p>
|
</dd>
|
<dt><code>-mmac_d16</code></dt>
|
<dd><a name="index-mmac_005fd16"></a>
|
<p>Replaced by <samp>-mmac-d16</samp>.
|
</p>
|
</dd>
|
<dt><code>-mspfp_compact</code></dt>
|
<dd><a name="index-mspfp_005fcompact"></a>
|
<p>Replaced by <samp>-mspfp-compact</samp>.
|
</p>
|
</dd>
|
<dt><code>-mspfp_fast</code></dt>
|
<dd><a name="index-mspfp_005ffast"></a>
|
<p>Replaced by <samp>-mspfp-fast</samp>.
|
</p>
|
</dd>
|
<dt><code>-mtune=<var>cpu</var></code></dt>
|
<dd><a name="index-mtune-2"></a>
|
<p>Values ‘<samp>arc600</samp>’, ‘<samp>arc601</samp>’, ‘<samp>arc700</samp>’ and
|
‘<samp>arc700-xmac</samp>’ for <var>cpu</var> are replaced by ‘<samp>ARC600</samp>’,
|
‘<samp>ARC601</samp>’, ‘<samp>ARC700</samp>’ and ‘<samp>ARC700-xmac</samp>’ respectively
|
</p>
|
</dd>
|
<dt><code>-multcost=<var>num</var></code></dt>
|
<dd><a name="index-multcost"></a>
|
<p>Replaced by <samp>-mmultcost</samp>.
|
</p>
|
</dd>
|
</dl>
|
|
<hr>
|
<div class="header">
|
<p>
|
Next: <a href="ARM-Options.html#ARM-Options" accesskey="n" rel="next">ARM Options</a>, Previous: <a href="Adapteva-Epiphany-Options.html#Adapteva-Epiphany-Options" accesskey="p" rel="prev">Adapteva Epiphany Options</a>, Up: <a href="Submodel-Options.html#Submodel-Options" accesskey="u" rel="up">Submodel Options</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p>
|
</div>
|
|
|
|
</body>
|
</html>
|
