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#include "platform.h"
/*
* We have to be very careful implementing WordS_quot and WordS_rem using / and %
* because C allows
* "The direction of truncation for / and the sign of the result for % are
* machine-dependent for negative operands, ..." (K&R p. 41) (See also p. 205.)
* On the other hand, the SML Basis library spec is completely nailed down.
* On x86, gcc implements / and % using idiv, which fortunately does have the
* same semantics as the SML Basis library. However, gcc's optimizer sometimes
* takes advantage of the flexibility in the C spec when one of the arguments
* is a constant, producing incorrect results. So, we have two options:
*
* Put them in a separate file, all by themselves, without a static inline, and
* use / and % where we know gcc's optimer can't hurt us.
* OR
* Use inline assembler.
*
* We've gone for the first option because of simplicity, and because
* quot and rem are only used with the C codegen. If you really want
* speed, you could try inline assembler.
*
* To get this working on another architecture, you need to check how gcc
* implements / and %.
*/
#if ! (defined(__alpha__) || defined (__amd64__) || defined (__hppa__) || defined (__i386__) || defined(__ia64__) || defined(__mips__) || defined (__ppc__) || defined (__powerpc__) || defined (__powerpc64__) || defined (__sparc__) || defined (__arm__) || defined(__s390__))
#error check that C {/,%} correctly implement {quot,rem} from the basis library
#endif
#include "Word-consts.h"
#include "Word-ops.h"
#include "Word-check.h"
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