🚀 go-pugleaf

In article <7899@charon.cwi.nl> dik@cwi.nl (Dik T. Winter) writes:
>But wait.  SPARC version 7 does not have an integer multiply instruction,
>it uses multiply step.  When you code the multiply in assembly you will
>find that you get a 64 bit result, but in C it is not possible to
>retrieve that result.  Doing it with inline assembly is not what you
>want in general (>32 instructions inline assembly), so you do it
>out-of-line.  Hence it is not sufficient to have good inliners, on
>some platforms you need out of line assembly routines to do what you
>want, and no, the compilers do not help.  (The same holds for HP-PA 1,
>IBM PC-RT, AMD 29k and a few more.)  So the operation is available but
>you do not get it.
>
>So let's see.  You promote the GCC interface with asm.  How do you
>code the 32x32->64 multiply on the SPARC in GCC?

Include the following in every source file:

	static inline long long mul32to64 (long i, long j)
	{
		whatever asm magic one requires
	}

This terribly inelegant; if you want elegance BUY a compiler for the
machine which has 64 bit longs and use:

	long i64;
	int i32, j32;
	i64 = (long) i32 * (long) j32;

If the compiler insists on promoting i32 and j32 to 64 bits before the
multiplication, ask for your money back.

Solutions exists for many of the specific problems which have been
discussed in this thread: most of the free ones are inelegant and most
of the elegant ones are expensive.