Fri Oct 1 10:56:06 1999 Bernd Schmidt <bernds@cygnus.co.uk>
+ * md.texi (No Constraints): Delete section.
* Makefile.in (genattrtab.o): Don't depend on "insn-config.h".
* final.c (final_scan_insn): We always have register constraints.
* genattrtab.c: Don't include "insn-config.h".
* Class Preferences:: Constraints guide which hard register to put things in.
* Modifiers:: More precise control over effects of constraints.
* Machine Constraints:: Existing constraints for some particular machines.
-* No Constraints:: Describing a clean machine without constraints.
@end menu
@end ifset
@end table
@ifset INTERNALS
-@node No Constraints
-@subsection Not Using Constraints
-@cindex no constraints
-@cindex not using constraints
-
-Some machines are so clean that operand constraints are not required. For
-example, on the Vax, an operand valid in one context is valid in any other
-context. On such a machine, every operand constraint would be @samp{g},
-excepting only operands of ``load address'' instructions which are
-written as if they referred to a memory location's contents but actual
-refer to its address. They would have constraint @samp{p}.
-
-@cindex empty constraints
-For such machines, instead of writing @samp{g} and @samp{p} for all
-the constraints, you can choose to write a description with empty constraints.
-Then you write @samp{""} for the constraint in every @code{match_operand}.
-Address operands are identified by writing an @code{address} expression
-around the @code{match_operand}, not by their constraints.
-
-When the machine description has just empty constraints, certain parts
-of compilation are skipped, making the compiler faster. However,
-few machines actually do not need constraints; all machine descriptions
-now in existence use constraints.
-@end ifset
-
-@ifset INTERNALS
@node Standard Names
@section Standard Pattern Names For Generation
@cindex standard pattern names
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