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<h5 class="subsubsection">16.23.1.3 Mode Iterator Examples</h5>
<p>Here is an example from the MIPS port. It defines the following
modes and attributes (among others):
<pre class="smallexample"> (define_mode_iterator GPR [SI (DI "TARGET_64BIT")])
(define_mode_attr d [(SI "") (DI "d")])
</pre>
<p>and uses the following template to define both <code>subsi3</code>
and <code>subdi3</code>:
<pre class="smallexample"> (define_insn "sub<mode>3"
[(set (match_operand:GPR 0 "register_operand" "=d")
(minus:GPR (match_operand:GPR 1 "register_operand" "d")
(match_operand:GPR 2 "register_operand" "d")))]
""
"<d>subu\t%0,%1,%2"
[(set_attr "type" "arith")
(set_attr "mode" "<MODE>")])
</pre>
<p>This is exactly equivalent to:
<pre class="smallexample"> (define_insn "subsi3"
[(set (match_operand:SI 0 "register_operand" "=d")
(minus:SI (match_operand:SI 1 "register_operand" "d")
(match_operand:SI 2 "register_operand" "d")))]
""
"subu\t%0,%1,%2"
[(set_attr "type" "arith")
(set_attr "mode" "SI")])
(define_insn "subdi3"
[(set (match_operand:DI 0 "register_operand" "=d")
(minus:DI (match_operand:DI 1 "register_operand" "d")
(match_operand:DI 2 "register_operand" "d")))]
""
"dsubu\t%0,%1,%2"
[(set_attr "type" "arith")
(set_attr "mode" "DI")])
</pre>
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