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<h4 class="subsection">3.17.34 picoChip Options</h4>
<p><a name="index-picoChip-options-2191"></a>
These &lsquo;<samp><span class="samp">-m</span></samp>&rsquo; options are defined for picoChip implementations:
<dl>
<dt><code>-mae=</code><var>ae_type</var><dd><a name="index-mcpu-2192"></a>Set the instruction set, register set, and instruction scheduling
parameters for array element type <var>ae_type</var>. Supported values
for <var>ae_type</var> are &lsquo;<samp><span class="samp">ANY</span></samp>&rsquo;, &lsquo;<samp><span class="samp">MUL</span></samp>&rsquo;, and &lsquo;<samp><span class="samp">MAC</span></samp>&rsquo;.
<p><samp><span class="option">-mae=ANY</span></samp> selects a completely generic AE type. Code
generated with this option runs on any of the other AE types. The
code is not as efficient as it would be if compiled for a specific
AE type, and some types of operation (e.g., multiplication) do not
work properly on all types of AE.
<p><samp><span class="option">-mae=MUL</span></samp> selects a MUL AE type. This is the most useful AE type
for compiled code, and is the default.
<p><samp><span class="option">-mae=MAC</span></samp> selects a DSP-style MAC AE. Code compiled with this
option may suffer from poor performance of byte (char) manipulation,
since the DSP AE does not provide hardware support for byte load/stores.
<br><dt><code>-msymbol-as-address</code><dd>Enable the compiler to directly use a symbol name as an address in a
load/store instruction, without first loading it into a
register. Typically, the use of this option generates larger
programs, which run faster than when the option isn't used. However, the
results vary from program to program, so it is left as a user option,
rather than being permanently enabled.
<br><dt><code>-mno-inefficient-warnings</code><dd>Disables warnings about the generation of inefficient code. These
warnings can be generated, for example, when compiling code that
performs byte-level memory operations on the MAC AE type. The MAC AE has
no hardware support for byte-level memory operations, so all byte
load/stores must be synthesized from word load/store operations. This is
inefficient and a warning is generated to indicate
that you should rewrite the code to avoid byte operations, or to target
an AE type that has the necessary hardware support. This option disables
these warnings.
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