[PATCH] haifa-sched.c and optabs.c latent bugs

[law@redhat.com]

In message <200204282033.QAA28310@makai.watson.ibm.com>, David Edelsohn writes:
 > 	As I debug the scheduler stack usage bug, I have found a few
 > latent bugs which should be fixed.
[ .. SCHED_GROUP_ stuff omitted ..]

 > 
 > 	The optabs bug is a combination of "subtarget" and "expand_binop".
 > I performed a code review of optabs.c and I could only find the one case
 > addressed by my patch where the various prerequisites can occur.  The
 > requirements are a pseudo with split lifetimes that is resurrected by a
 > bare clobber not associated with a libcall/no_conflict block.  This patch
 > creates a new pseudo for the multi-word computation, setting the result to
 > the previous target instead of computing the result in the target.  This
 > also should allow a register allocator and schedule extra flexibility when
 > arranging these disjoint computations.
 > 
 > 	This was bootstrapped on powerpc-ibm-aix4.3.3.0.
 > 
 > Thanks, David
 > 
 > 	* optabs.c (expand_binop): Fix nwords sign warnings.
 > 	Always generate pseudo for add_optab.
Retested (i686-pc-linux-gnu) and installed into the mainline sources.

jeff