mips64 inline question

[d p chang]

I'm still going through the mips-linux archives, but I'm having a
problem w/ what appears to be a working (for simple programs) cross
compiler (that I built from cvs a few days ago).

The code in question is in delay.h as:

extern __inline__ void __udelay(unsigned long usecs, unsigned long lpj)
{
	unsigned long lo;

	usecs *= 0x00068db8bac710cbUL;		/* 2**64 / (1000000 / HZ) */
	__asm__ ("dmultu\t%2,%3"
                 :"=h" (usecs), "=l" (lo)
                 :"r" (usecs),"r" (lpj));
	__delay(hi);
}

This produces the following errors (the last part I assume comes from
the first errors):

panic.c: In function `panic':
/home/dpc/src/linux-2.4.17/include/asm/delay.h:47: impossible register constraint in `asm'
/home/dpc/src/linux-2.4.17/include/asm/delay.h:47: impossible register constraint in `asm'
/home/dpc/src/linux-2.4.17/include/asm/delay.h:47: impossible register constraint in `asm'
/home/dpc/src/linux-2.4.17/include/asm/delay.h:47: impossible register constraint in `asm'
/home/dpc/src/linux-2.4.17/include/asm/delay.h:47: impossible register constraint in `asm'
/home/dpc/src/linux-2.4.17/include/asm/delay.h:47: impossible register constraint in `asm'
panic.c:101: unrecognizable insn:
(insn 300 299 423 (parallel[ 
            (set (reg:DI 10 t2)
                (asm_operands:DI ("dmultu	%2,%3") ("=h") 0[ 
                        (reg:DI 2 v0 [157])
                        (reg:DI 4 a0 [166])
                    ] 
                    [ 
                        (asm_input:DI ("r"))
                        (asm_input:DI ("r"))
                    ]  ("/home/dpc/src/linux-2.4.17/include/asm/delay.h") 47))
            (set (reg:DI 12 t4)
                (asm_operands:DI ("dmultu	%2,%3") ("=l") 1[ 
                        (reg:DI 2 v0 [157])
                        (reg:DI 4 a0 [166])
                    ] 
                    [ 
                        (asm_input:DI ("r"))
                        (asm_input:DI ("r"))
                    ]  ("/home/dpc/src/linux-2.4.17/include/asm/delay.h") 47))
        ] ) -1 (insn_list 288 (nil))
    (nil))
panic.c:101: confused by earlier errors, bailing out

I've tried playing around w/ the source registers some (expanding the
inline to include explicit moves to registers etc), but it appears
that the destination hi/lo register constraints are upsetting gcc. 

Am I missing something else from the docs?


p