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   6 <TITLE>The SUIF Version 1 Library - Call-By-Ref Annotes</TITLE>
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  17 <H3><A NAME="SEC76" HREF="suif1_toc.html#TOC76">Call-By-Reference Annotations</A></H3>
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  19 <A NAME="IDX566"></A>
  20 <A NAME="IDX567"></A>
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  24 Fortran and other languages pass procedure parameters by reference but
  25 SUIF uses call-by-value.  To implement call-by-reference parameters,
  26 SUIF passes pointers to the actual parameters and then dereferences
  27 those pointers when the formal parameters are used.  While this is
  28 perfectly adequate for many compiler passes, the pointer dereferences
  29 are difficult to handle in some high-level Fortran passes.  The SUIF
  30 Fortran mode automatically converts the code to make it appear that the
  31 parameters are passed by reference.  The library uses two predefined
  32 annotations to implement this.
  33
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  35 <DL COMPACT>
  36
  37 <DT><CODE>k_call_by_ref</CODE>
  38 <DD>
  39 <A NAME="IDX568"></A>
  40 The Fortran front-end puts this annotation on pointer types that are
  41 used to implement call-by-reference parameter passing.  The library uses
  42 this to detect parameters that should be modified when converting to
  43 Fortran mode.  This annotation has no data on its <CODE>immed</CODE> list.
  44
  45 <DT><CODE>k_orig_type</CODE>
  46 <DD>
  47 <A NAME="IDX569"></A>
  48 While in Fortran mode, the types of the call-by-reference parameters are
  49 temporarily replaced.  The <CODE>orig_type</CODE> annotations are attached
  50 to the parameter variables to record their original types.  The
  51 <CODE>immed</CODE> list contains a single entry, the original pointer type of
  52 the parameter.  These annotations are never written to the output files.
  53 </DL>
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