gccint: Reading RTL

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1 14.22 Reading RTL
1 =================
1 
1 To read an RTL object from a file, call 'read_rtx'.  It takes one
1 argument, a stdio stream, and returns a single RTL object.  This routine
1 is defined in 'read-rtl.c'.  It is not available in the compiler itself,
1 only the various programs that generate the compiler back end from the
1 machine description.
1 
1  People frequently have the idea of using RTL stored as text in a file
1 as an interface between a language front end and the bulk of GCC.  This
1 idea is not feasible.
1 
1  GCC was designed to use RTL internally only.  Correct RTL for a given
1 program is very dependent on the particular target machine.  And the RTL
1 does not contain all the information about the program.
1 
1  The proper way to interface GCC to a new language front end is with the
1 "tree" data structure, described in the files 'tree.h' and 'tree.def'.
1 The documentation for this structure (⇒GENERIC) is incomplete.
1