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Delete !REGISTER_CONSTRAINTS code 

From-SVN: r29754
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Bernd Schmidt 1999-10-01 10:26:46 +00:00 committed by Bernd Schmidt
parent 19af645506
commit 3cf965b7f6
2 changed files with 1 additions and 27 deletions
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1
gcc/ChangeLog
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@ -1,5 +1,6 @@
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".

27
gcc/md.texi
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@ -667,7 +667,6 @@ have. Constraints can also require two operands to match.
* 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
@ -1659,32 +1658,6 @@ Even register
@end table
@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