You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
368 lines
18 KiB
HTML
368 lines
18 KiB
HTML
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
|
|
<html>
|
|
<!-- Copyright (C) 1988-2018 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 6.4, http://www.gnu.org/software/texinfo/ -->
|
|
<head>
|
|
<title>S/390 and zSeries Options (Using the GNU Compiler Collection (GCC))</title>
|
|
|
|
<meta name="description" content="S/390 and zSeries Options (Using the GNU Compiler Collection (GCC))">
|
|
<meta name="keywords" content="S/390 and zSeries Options (Using the GNU Compiler Collection (GCC))">
|
|
<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="Score-Options.html#Score-Options" rel="next" title="Score Options">
|
|
<link href="RX-Options.html#RX-Options" rel="prev" title="RX Options">
|
|
<style type="text/css">
|
|
<!--
|
|
a.summary-letter {text-decoration: none}
|
|
blockquote.indentedblock {margin-right: 0em}
|
|
blockquote.smallindentedblock {margin-right: 0em; font-size: smaller}
|
|
blockquote.smallquotation {font-size: smaller}
|
|
div.display {margin-left: 3.2em}
|
|
div.example {margin-left: 3.2em}
|
|
div.lisp {margin-left: 3.2em}
|
|
div.smalldisplay {margin-left: 3.2em}
|
|
div.smallexample {margin-left: 3.2em}
|
|
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.nolinebreak {white-space: nowrap}
|
|
span.roman {font-family: initial; font-weight: normal}
|
|
span.sansserif {font-family: sans-serif; font-weight: normal}
|
|
ul.no-bullet {list-style: none}
|
|
-->
|
|
</style>
|
|
|
|
|
|
</head>
|
|
|
|
<body lang="en">
|
|
<a name="S_002f390-and-zSeries-Options"></a>
|
|
<div class="header">
|
|
<p>
|
|
Next: <a href="Score-Options.html#Score-Options" accesskey="n" rel="next">Score Options</a>, Previous: <a href="RX-Options.html#RX-Options" accesskey="p" rel="prev">RX 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="S_002f390-and-zSeries-Options-1"></a>
|
|
<h4 class="subsection">3.18.42 S/390 and zSeries Options</h4>
|
|
<a name="index-S_002f390-and-zSeries-Options"></a>
|
|
|
|
<p>These are the ‘<samp>-m</samp>’ options defined for the S/390 and zSeries architecture.
|
|
</p>
|
|
<dl compact="compact">
|
|
<dt><code>-mhard-float</code></dt>
|
|
<dt><code>-msoft-float</code></dt>
|
|
<dd><a name="index-mhard_002dfloat-6"></a>
|
|
<a name="index-msoft_002dfloat-10"></a>
|
|
<p>Use (do not use) the hardware floating-point instructions and registers
|
|
for floating-point operations. When <samp>-msoft-float</samp> is specified,
|
|
functions in <samp>libgcc.a</samp> are used to perform floating-point
|
|
operations. When <samp>-mhard-float</samp> is specified, the compiler
|
|
generates IEEE floating-point instructions. This is the default.
|
|
</p>
|
|
</dd>
|
|
<dt><code>-mhard-dfp</code></dt>
|
|
<dt><code>-mno-hard-dfp</code></dt>
|
|
<dd><a name="index-mhard_002ddfp-1"></a>
|
|
<a name="index-mno_002dhard_002ddfp-1"></a>
|
|
<p>Use (do not use) the hardware decimal-floating-point instructions for
|
|
decimal-floating-point operations. When <samp>-mno-hard-dfp</samp> is
|
|
specified, functions in <samp>libgcc.a</samp> are used to perform
|
|
decimal-floating-point operations. When <samp>-mhard-dfp</samp> is
|
|
specified, the compiler generates decimal-floating-point hardware
|
|
instructions. This is the default for <samp>-march=z9-ec</samp> or higher.
|
|
</p>
|
|
</dd>
|
|
<dt><code>-mlong-double-64</code></dt>
|
|
<dt><code>-mlong-double-128</code></dt>
|
|
<dd><a name="index-mlong_002ddouble_002d64"></a>
|
|
<a name="index-mlong_002ddouble_002d128"></a>
|
|
<p>These switches control the size of <code>long double</code> type. A size
|
|
of 64 bits makes the <code>long double</code> type equivalent to the <code>double</code>
|
|
type. This is the default.
|
|
</p>
|
|
</dd>
|
|
<dt><code>-mbackchain</code></dt>
|
|
<dt><code>-mno-backchain</code></dt>
|
|
<dd><a name="index-mbackchain"></a>
|
|
<a name="index-mno_002dbackchain"></a>
|
|
<p>Store (do not store) the address of the caller’s frame as backchain pointer
|
|
into the callee’s stack frame.
|
|
A backchain may be needed to allow debugging using tools that do not understand
|
|
DWARF call frame information.
|
|
When <samp>-mno-packed-stack</samp> is in effect, the backchain pointer is stored
|
|
at the bottom of the stack frame; when <samp>-mpacked-stack</samp> is in effect,
|
|
the backchain is placed into the topmost word of the 96/160 byte register
|
|
save area.
|
|
</p>
|
|
<p>In general, code compiled with <samp>-mbackchain</samp> is call-compatible with
|
|
code compiled with <samp>-mmo-backchain</samp>; however, use of the backchain
|
|
for debugging purposes usually requires that the whole binary is built with
|
|
<samp>-mbackchain</samp>. Note that the combination of <samp>-mbackchain</samp>,
|
|
<samp>-mpacked-stack</samp> and <samp>-mhard-float</samp> is not supported. In order
|
|
to build a linux kernel use <samp>-msoft-float</samp>.
|
|
</p>
|
|
<p>The default is to not maintain the backchain.
|
|
</p>
|
|
</dd>
|
|
<dt><code>-mpacked-stack</code></dt>
|
|
<dt><code>-mno-packed-stack</code></dt>
|
|
<dd><a name="index-mpacked_002dstack"></a>
|
|
<a name="index-mno_002dpacked_002dstack"></a>
|
|
<p>Use (do not use) the packed stack layout. When <samp>-mno-packed-stack</samp> is
|
|
specified, the compiler uses the all fields of the 96/160 byte register save
|
|
area only for their default purpose; unused fields still take up stack space.
|
|
When <samp>-mpacked-stack</samp> is specified, register save slots are densely
|
|
packed at the top of the register save area; unused space is reused for other
|
|
purposes, allowing for more efficient use of the available stack space.
|
|
However, when <samp>-mbackchain</samp> is also in effect, the topmost word of
|
|
the save area is always used to store the backchain, and the return address
|
|
register is always saved two words below the backchain.
|
|
</p>
|
|
<p>As long as the stack frame backchain is not used, code generated with
|
|
<samp>-mpacked-stack</samp> is call-compatible with code generated with
|
|
<samp>-mno-packed-stack</samp>. Note that some non-FSF releases of GCC 2.95 for
|
|
S/390 or zSeries generated code that uses the stack frame backchain at run
|
|
time, not just for debugging purposes. Such code is not call-compatible
|
|
with code compiled with <samp>-mpacked-stack</samp>. Also, note that the
|
|
combination of <samp>-mbackchain</samp>,
|
|
<samp>-mpacked-stack</samp> and <samp>-mhard-float</samp> is not supported. In order
|
|
to build a linux kernel use <samp>-msoft-float</samp>.
|
|
</p>
|
|
<p>The default is to not use the packed stack layout.
|
|
</p>
|
|
</dd>
|
|
<dt><code>-msmall-exec</code></dt>
|
|
<dt><code>-mno-small-exec</code></dt>
|
|
<dd><a name="index-msmall_002dexec"></a>
|
|
<a name="index-mno_002dsmall_002dexec"></a>
|
|
<p>Generate (or do not generate) code using the <code>bras</code> instruction
|
|
to do subroutine calls.
|
|
This only works reliably if the total executable size does not
|
|
exceed 64k. The default is to use the <code>basr</code> instruction instead,
|
|
which does not have this limitation.
|
|
</p>
|
|
</dd>
|
|
<dt><code>-m64</code></dt>
|
|
<dt><code>-m31</code></dt>
|
|
<dd><a name="index-m64-2"></a>
|
|
<a name="index-m31"></a>
|
|
<p>When <samp>-m31</samp> is specified, generate code compliant to the
|
|
GNU/Linux for S/390 ABI. When <samp>-m64</samp> is specified, generate
|
|
code compliant to the GNU/Linux for zSeries ABI. This allows GCC in
|
|
particular to generate 64-bit instructions. For the ‘<samp>s390</samp>’
|
|
targets, the default is <samp>-m31</samp>, while the ‘<samp>s390x</samp>’
|
|
targets default to <samp>-m64</samp>.
|
|
</p>
|
|
</dd>
|
|
<dt><code>-mzarch</code></dt>
|
|
<dt><code>-mesa</code></dt>
|
|
<dd><a name="index-mzarch"></a>
|
|
<a name="index-mesa"></a>
|
|
<p>When <samp>-mzarch</samp> is specified, generate code using the
|
|
instructions available on z/Architecture.
|
|
When <samp>-mesa</samp> is specified, generate code using the
|
|
instructions available on ESA/390. Note that <samp>-mesa</samp> is
|
|
not possible with <samp>-m64</samp>.
|
|
When generating code compliant to the GNU/Linux for S/390 ABI,
|
|
the default is <samp>-mesa</samp>. When generating code compliant
|
|
to the GNU/Linux for zSeries ABI, the default is <samp>-mzarch</samp>.
|
|
</p>
|
|
</dd>
|
|
<dt><code>-mhtm</code></dt>
|
|
<dt><code>-mno-htm</code></dt>
|
|
<dd><a name="index-mhtm-1"></a>
|
|
<a name="index-mno_002dhtm-1"></a>
|
|
<p>The <samp>-mhtm</samp> option enables a set of builtins making use of
|
|
instructions available with the transactional execution facility
|
|
introduced with the IBM zEnterprise EC12 machine generation
|
|
<a href="S_002f390-System-z-Built_002din-Functions.html#S_002f390-System-z-Built_002din-Functions">S/390 System z Built-in Functions</a>.
|
|
<samp>-mhtm</samp> is enabled by default when using <samp>-march=zEC12</samp>.
|
|
</p>
|
|
</dd>
|
|
<dt><code>-mvx</code></dt>
|
|
<dt><code>-mno-vx</code></dt>
|
|
<dd><a name="index-mvx"></a>
|
|
<a name="index-mno_002dvx"></a>
|
|
<p>When <samp>-mvx</samp> is specified, generate code using the instructions
|
|
available with the vector extension facility introduced with the IBM
|
|
z13 machine generation.
|
|
This option changes the ABI for some vector type values with regard to
|
|
alignment and calling conventions. In case vector type values are
|
|
being used in an ABI-relevant context a GAS ‘<samp>.gnu_attribute</samp>’
|
|
command will be added to mark the resulting binary with the ABI used.
|
|
<samp>-mvx</samp> is enabled by default when using <samp>-march=z13</samp>.
|
|
</p>
|
|
</dd>
|
|
<dt><code>-mzvector</code></dt>
|
|
<dt><code>-mno-zvector</code></dt>
|
|
<dd><a name="index-mzvector"></a>
|
|
<a name="index-mno_002dzvector"></a>
|
|
<p>The <samp>-mzvector</samp> option enables vector language extensions and
|
|
builtins using instructions available with the vector extension
|
|
facility introduced with the IBM z13 machine generation.
|
|
This option adds support for ‘<samp>vector</samp>’ to be used as a keyword to
|
|
define vector type variables and arguments. ‘<samp>vector</samp>’ is only
|
|
available when GNU extensions are enabled. It will not be expanded
|
|
when requesting strict standard compliance e.g. with <samp>-std=c99</samp>.
|
|
In addition to the GCC low-level builtins <samp>-mzvector</samp> enables
|
|
a set of builtins added for compatibility with AltiVec-style
|
|
implementations like Power and Cell. In order to make use of these
|
|
builtins the header file <samp>vecintrin.h</samp> needs to be included.
|
|
<samp>-mzvector</samp> is disabled by default.
|
|
</p>
|
|
</dd>
|
|
<dt><code>-mmvcle</code></dt>
|
|
<dt><code>-mno-mvcle</code></dt>
|
|
<dd><a name="index-mmvcle"></a>
|
|
<a name="index-mno_002dmvcle"></a>
|
|
<p>Generate (or do not generate) code using the <code>mvcle</code> instruction
|
|
to perform block moves. When <samp>-mno-mvcle</samp> is specified,
|
|
use a <code>mvc</code> loop instead. This is the default unless optimizing for
|
|
size.
|
|
</p>
|
|
</dd>
|
|
<dt><code>-mdebug</code></dt>
|
|
<dt><code>-mno-debug</code></dt>
|
|
<dd><a name="index-mdebug-1"></a>
|
|
<a name="index-mno_002ddebug"></a>
|
|
<p>Print (or do not print) additional debug information when compiling.
|
|
The default is to not print debug information.
|
|
</p>
|
|
</dd>
|
|
<dt><code>-march=<var>cpu-type</var></code></dt>
|
|
<dd><a name="index-march-11"></a>
|
|
<p>Generate code that runs on <var>cpu-type</var>, which is the name of a
|
|
system representing a certain processor type. Possible values for
|
|
<var>cpu-type</var> are ‘<samp>z900</samp>’/‘<samp>arch5</samp>’, ‘<samp>z990</samp>’/‘<samp>arch6</samp>’,
|
|
‘<samp>z9-109</samp>’, ‘<samp>z9-ec</samp>’/‘<samp>arch7</samp>’, ‘<samp>z10</samp>’/‘<samp>arch8</samp>’,
|
|
‘<samp>z196</samp>’/‘<samp>arch9</samp>’, ‘<samp>zEC12</samp>’, ‘<samp>z13</samp>’/‘<samp>arch11</samp>’,
|
|
‘<samp>z14</samp>’/‘<samp>arch12</samp>’, and ‘<samp>native</samp>’.
|
|
</p>
|
|
<p>The default is <samp>-march=z900</samp>. ‘<samp>g5</samp>’/‘<samp>arch3</samp>’ and
|
|
‘<samp>g6</samp>’ are deprecated and will be removed with future releases.
|
|
</p>
|
|
<p>Specifying ‘<samp>native</samp>’ as cpu type can be used to select the best
|
|
architecture option for the host processor.
|
|
<samp>-march=native</samp> has no effect if GCC does not recognize the
|
|
processor.
|
|
</p>
|
|
</dd>
|
|
<dt><code>-mtune=<var>cpu-type</var></code></dt>
|
|
<dd><a name="index-mtune-13"></a>
|
|
<p>Tune to <var>cpu-type</var> everything applicable about the generated code,
|
|
except for the ABI and the set of available instructions.
|
|
The list of <var>cpu-type</var> values is the same as for <samp>-march</samp>.
|
|
The default is the value used for <samp>-march</samp>.
|
|
</p>
|
|
</dd>
|
|
<dt><code>-mtpf-trace</code></dt>
|
|
<dt><code>-mno-tpf-trace</code></dt>
|
|
<dd><a name="index-mtpf_002dtrace"></a>
|
|
<a name="index-mno_002dtpf_002dtrace"></a>
|
|
<p>Generate code that adds (does not add) in TPF OS specific branches to trace
|
|
routines in the operating system. This option is off by default, even
|
|
when compiling for the TPF OS.
|
|
</p>
|
|
</dd>
|
|
<dt><code>-mfused-madd</code></dt>
|
|
<dt><code>-mno-fused-madd</code></dt>
|
|
<dd><a name="index-mfused_002dmadd-4"></a>
|
|
<a name="index-mno_002dfused_002dmadd-4"></a>
|
|
<p>Generate code that uses (does not use) the floating-point multiply and
|
|
accumulate instructions. These instructions are generated by default if
|
|
hardware floating point is used.
|
|
</p>
|
|
</dd>
|
|
<dt><code>-mwarn-framesize=<var>framesize</var></code></dt>
|
|
<dd><a name="index-mwarn_002dframesize"></a>
|
|
<p>Emit a warning if the current function exceeds the given frame size. Because
|
|
this is a compile-time check it doesn’t need to be a real problem when the program
|
|
runs. It is intended to identify functions that most probably cause
|
|
a stack overflow. It is useful to be used in an environment with limited stack
|
|
size e.g. the linux kernel.
|
|
</p>
|
|
</dd>
|
|
<dt><code>-mwarn-dynamicstack</code></dt>
|
|
<dd><a name="index-mwarn_002ddynamicstack"></a>
|
|
<p>Emit a warning if the function calls <code>alloca</code> or uses dynamically-sized
|
|
arrays. This is generally a bad idea with a limited stack size.
|
|
</p>
|
|
</dd>
|
|
<dt><code>-mstack-guard=<var>stack-guard</var></code></dt>
|
|
<dt><code>-mstack-size=<var>stack-size</var></code></dt>
|
|
<dd><a name="index-mstack_002dguard"></a>
|
|
<a name="index-mstack_002dsize"></a>
|
|
<p>If these options are provided the S/390 back end emits additional instructions in
|
|
the function prologue that trigger a trap if the stack size is <var>stack-guard</var>
|
|
bytes above the <var>stack-size</var> (remember that the stack on S/390 grows downward).
|
|
If the <var>stack-guard</var> option is omitted the smallest power of 2 larger than
|
|
the frame size of the compiled function is chosen.
|
|
These options are intended to be used to help debugging stack overflow problems.
|
|
The additionally emitted code causes only little overhead and hence can also be
|
|
used in production-like systems without greater performance degradation. The given
|
|
values have to be exact powers of 2 and <var>stack-size</var> has to be greater than
|
|
<var>stack-guard</var> without exceeding 64k.
|
|
In order to be efficient the extra code makes the assumption that the stack starts
|
|
at an address aligned to the value given by <var>stack-size</var>.
|
|
The <var>stack-guard</var> option can only be used in conjunction with <var>stack-size</var>.
|
|
</p>
|
|
</dd>
|
|
<dt><code>-mhotpatch=<var>pre-halfwords</var>,<var>post-halfwords</var></code></dt>
|
|
<dd><a name="index-mhotpatch"></a>
|
|
<p>If the hotpatch option is enabled, a “hot-patching” function
|
|
prologue is generated for all functions in the compilation unit.
|
|
The funtion label is prepended with the given number of two-byte
|
|
NOP instructions (<var>pre-halfwords</var>, maximum 1000000). After
|
|
the label, 2 * <var>post-halfwords</var> bytes are appended, using the
|
|
largest NOP like instructions the architecture allows (maximum
|
|
1000000).
|
|
</p>
|
|
<p>If both arguments are zero, hotpatching is disabled.
|
|
</p>
|
|
<p>This option can be overridden for individual functions with the
|
|
<code>hotpatch</code> attribute.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
<hr>
|
|
<div class="header">
|
|
<p>
|
|
Next: <a href="Score-Options.html#Score-Options" accesskey="n" rel="next">Score Options</a>, Previous: <a href="RX-Options.html#RX-Options" accesskey="p" rel="prev">RX 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>
|