This kind of thing (from longlong.h) is never good news. Someone probably
needs to figure out what the `arm3' version is doing and why it doesn't work
on armv4. (It ought not to be using explicit hard registers either.)
/* SAM This does not work on arm4 */
#define umul_ppmm(xh, xl, a, b) \
__asm__ ("%@ Inlined umul_ppmm
mov %|r0, %2, lsr #16
mov %|r2, %3, lsr #16
bic %|r1, %2, %|r0, lsl #16
bic %|r2, %3, %|r2, lsl #16
mul %1, %|r1, %|r2
mul %|r2, %|r0, %|r2
mul %|r1, %0, %|r1
mul %0, %|r0, %0
adds %|r1, %|r2, %|r1
addcs %0, %0, #65536
adds %1, %1, %|r1, lsl #16
adc %0, %0, %|r1, lsr #16" \
: "=&r" ((USItype)(xh)), \
"=r" ((USItype)(xl)) \
: "r" ((USItype)(a)), \
"r" ((USItype)(b)) \
: "r0", "r1", "r2")
#elif __ARM_ARCH_4__
#define umul_ppmm(xh, xl, a, b) \
__asm__ ("%@ Inlined umul_ppmm
umull %r1, %r0, %r2, %r3" \
: "=&r" ((USItype)(xh)), \
"=r" ((USItype)(xl)) \
: "r" ((USItype)(a)), \
"r" ((USItype)(b)) \
: "r0", "r1")
#else
#error Untested architecture
#endif
p.
