| Message ID | 16372019.BFlLRod3Eu@wuerfel (mailing list archive) |
|---|---|
| State | Not Applicable |
| Delegated to: | Herbert Xu |
| Headers | show |
diff --git a/lib/mpi/longlong.h b/lib/mpi/longlong.h index aac511417ad1..c4dbdb506174 100644 --- a/lib/mpi/longlong.h +++ b/lib/mpi/longlong.h @@ -216,7 +216,7 @@ extern UDItype __udiv_qrnnd(UDItype *, UDItype, UDItype, UDItype); __asm__ ("%@ Inlined umul_ppmm\n" \ "umull %r1, %r0, %r2, %r3" \ : "=&r" ((USItype)(xh)), \ - "=r" ((USItype)(xl)) \ + "=&r" ((USItype)(xl)) \ : "r" ((USItype)(a)), \ "r" ((USItype)(b)) \ : "r0", "r1")
A wrapper around the umull assembly instruction might reuse the input register as an output, which is undefined on some ARM machines, as pointed out by this assembler warning: CC lib/mpi/generic_mpih-mul1.o /tmp/ccxJuxIy.s: Assembler messages: /tmp/ccxJuxIy.s:53: rdhi, rdlo and rm must all be different CC lib/mpi/generic_mpih-mul2.o /tmp/ccI0scAD.s: Assembler messages: /tmp/ccI0scAD.s:53: rdhi, rdlo and rm must all be different CC lib/mpi/generic_mpih-mul3.o /tmp/ccMvVQcp.s: Assembler messages: /tmp/ccMvVQcp.s:53: rdhi, rdlo and rm must all be different This changes the constraints to force different registers to be used as output. Signed-off-by: Arnd Bergmann <arnd@arnd.de> --- Not sure who would be the best person to pick this patch up. -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html