convert I2DEST to the mode of the source of NEWPAT if we can. */
m_split = split_insns (newpat, i3);
- if (m_split == 0)
+
+ /* We can only use I2DEST as a scratch reg if it doesn't overlap any
+ inputs of NEWPAT. */
+
+ /* ??? If I2DEST is not safe, and I1DEST exists, then it would be
+ possible to try that as a scratch reg. This would require adding
+ more code to make it work though. */
+
+ if (m_split == 0 && ! reg_overlap_mentioned_p (ni2dest, newpat))
{
/* If I2DEST is a hard register or the only use of a pseudo,
we can change its mode. */