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   6 <TITLE>The SUIF Version 1 Library - Generic Instructions</TITLE>
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  17 <H2><A NAME="SEC39" HREF="suif1_toc.html#TOC39">Generic Instructions</A></H2>
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  25 To help support special-purpose extensions to SUIF, we have provided a
  26 generic class of instructions.  This is implemented in the <CODE>in_gen</CODE>
  27 class.  These generic instructions contain arbitrarily large arrays of
  28 source operands and a character string field to hold user-defined names
  29 that function as "sub-opcodes".  Generic instructions are not part of
  30 standard SUIF and most SUIF passes will not handle them.
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  36 Because it is difficult to add new opcodes to SUIF at run-time, the
  37 generic instructions all share the same <CODE>gen</CODE> opcode.  Instead,
  38 they are distinguished by user-defined names.  The <CODE>name</CODE> and
  39 <CODE>set_name</CODE> methods may be used to access these character string
  40 fields.  The <CODE>set_name</CODE> method automatically enters the name in the
  41 lexicon (see section <A HREF="suif1_102.html#SEC102">Lexicon</A>).
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  46 A generic instruction contains a pointer to an array of source operands.
  47 The base class <CODE>num_srcs</CODE> method may be used to determine the size
  48 of this array.  The size may be changed at any time using the
  49 <CODE>set_num_srcs</CODE> method.  If necessary, the array will be
  50 reallocated.  The elements of the source operand array can be accessed
  51 using the standard base class <CODE>src_op</CODE> and <CODE>set_src_op</CODE>
  52 methods.  See section <A HREF="suif1_28.html#SEC28">Source Operands</A>.
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