1<html lang="en"> 2<head> 3<title>picoChip Options - Using the GNU Compiler Collection (GCC)</title> 4<meta http-equiv="Content-Type" content="text/html"> 5<meta name="description" content="Using the GNU Compiler Collection (GCC)"> 6<meta name="generator" content="makeinfo 4.13"> 7<link title="Top" rel="start" href="index.html#Top"> 8<link rel="up" href="Submodel-Options.html#Submodel-Options" title="Submodel Options"> 9<link rel="prev" href="PDP_002d11-Options.html#PDP_002d11-Options" title="PDP-11 Options"> 10<link rel="next" href="PowerPC-Options.html#PowerPC-Options" title="PowerPC Options"> 11<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage"> 12<!-- 13Copyright (C) 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 141998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 152010 Free Software Foundation, Inc. 16 17Permission is granted to copy, distribute and/or modify this document 18under the terms of the GNU Free Documentation License, Version 1.3 or 19any later version published by the Free Software Foundation; with the 20Invariant Sections being ``Funding Free Software'', the Front-Cover 21Texts being (a) (see below), and with the Back-Cover Texts being (b) 22(see below). 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Supported values 66for <var>ae_type</var> are ‘<samp><span class="samp">ANY</span></samp>’, ‘<samp><span class="samp">MUL</span></samp>’, and ‘<samp><span class="samp">MAC</span></samp>’. 67 68 <p><samp><span class="option">-mae=ANY</span></samp> selects a completely generic AE type. Code 69generated with this option will run on any of the other AE types. The 70code will not be as efficient as it would be if compiled for a specific 71AE type, and some types of operation (e.g., multiplication) will not 72work properly on all types of AE. 73 74 <p><samp><span class="option">-mae=MUL</span></samp> selects a MUL AE type. This is the most useful AE type 75for compiled code, and is the default. 76 77 <p><samp><span class="option">-mae=MAC</span></samp> selects a DSP-style MAC AE. Code compiled with this 78option may suffer from poor performance of byte (char) manipulation, 79since the DSP AE does not provide hardware support for byte load/stores. 80 81 <br><dt><code>-msymbol-as-address</code><dd>Enable the compiler to directly use a symbol name as an address in a 82load/store instruction, without first loading it into a 83register. Typically, the use of this option will generate larger 84programs, which run faster than when the option isn't used. However, the 85results vary from program to program, so it is left as a user option, 86rather than being permanently enabled. 87 88 <br><dt><code>-mno-inefficient-warnings</code><dd>Disables warnings about the generation of inefficient code. These 89warnings can be generated, for example, when compiling code which 90performs byte-level memory operations on the MAC AE type. The MAC AE has 91no hardware support for byte-level memory operations, so all byte 92load/stores must be synthesized from word load/store operations. This is 93inefficient and a warning will be generated indicating to the programmer 94that they should rewrite the code to avoid byte operations, or to target 95an AE type which has the necessary hardware support. This option enables 96the warning to be turned off. 97 98 </dl> 99 100 </body></html> 101 102