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  64. Next: <a href="PowerPC-Options.html#PowerPC-Options" accesskey="n" rel="next">PowerPC Options</a>, Previous: <a href="PDP_002d11-Options.html#PDP_002d11-Options" accesskey="p" rel="prev">PDP-11 Options</a>, Up: <a href="Submodel-Options.html#Submodel-Options" accesskey="u" rel="up">Submodel Options</a> &nbsp; [<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>
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  67. <a name="picoChip-Options-1"></a>
  68. <h4 class="subsection">3.19.39 picoChip Options</h4>
  69. <a name="index-picoChip-options"></a>
  70. <p>These &lsquo;<samp>-m</samp>&rsquo; options are defined for picoChip implementations:
  71. </p>
  72. <dl compact="compact">
  73. <dt><code>-mae=<var>ae_type</var></code></dt>
  74. <dd><a name="index-mcpu-7"></a>
  75. <p>Set the instruction set, register set, and instruction scheduling
  76. parameters for array element type <var>ae_type</var>. Supported values
  77. for <var>ae_type</var> are &lsquo;<samp>ANY</samp>&rsquo;, &lsquo;<samp>MUL</samp>&rsquo;, and &lsquo;<samp>MAC</samp>&rsquo;.
  78. </p>
  79. <p><samp>-mae=ANY</samp> selects a completely generic AE type. Code
  80. generated with this option runs on any of the other AE types. The
  81. code is not as efficient as it would be if compiled for a specific
  82. AE type, and some types of operation (e.g., multiplication) do not
  83. work properly on all types of AE.
  84. </p>
  85. <p><samp>-mae=MUL</samp> selects a MUL AE type. This is the most useful AE type
  86. for compiled code, and is the default.
  87. </p>
  88. <p><samp>-mae=MAC</samp> selects a DSP-style MAC AE. Code compiled with this
  89. option may suffer from poor performance of byte (char) manipulation,
  90. since the DSP AE does not provide hardware support for byte load/stores.
  91. </p>
  92. </dd>
  93. <dt><code>-msymbol-as-address</code></dt>
  94. <dd><p>Enable the compiler to directly use a symbol name as an address in a
  95. load/store instruction, without first loading it into a
  96. register. Typically, the use of this option generates larger
  97. programs, which run faster than when the option isn&rsquo;t used. However, the
  98. results vary from program to program, so it is left as a user option,
  99. rather than being permanently enabled.
  100. </p>
  101. </dd>
  102. <dt><code>-mno-inefficient-warnings</code></dt>
  103. <dd><p>Disables warnings about the generation of inefficient code. These
  104. warnings can be generated, for example, when compiling code that
  105. performs byte-level memory operations on the MAC AE type. The MAC AE has
  106. no hardware support for byte-level memory operations, so all byte
  107. load/stores must be synthesized from word load/store operations. This is
  108. inefficient and a warning is generated to indicate
  109. that you should rewrite the code to avoid byte operations, or to target
  110. an AE type that has the necessary hardware support. This option disables
  111. these warnings.
  112. </p>
  113. </dd>
  114. </dl>
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