Evan Cheng c92da3882e There are times when the coalescer would not coalesce away a copy but the copy ... can be eliminated by the allocator is the destination and source targets the same register. The most common case is when the source and destination registers are in different class. For example, on x86 mov32to32_ targets GR32_ which contains a subset of the registers in GR32. The allocator can do 2 things: 1. Set the preferred allocation for the destination of a copy to that of its source. 2. After allocation is done, change the allocation of a copy destination (if legal) so the copy can be eliminated. This eliminates 443 extra moves from 403.gcc. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@43662 91177308-0d34-0410-b5e6-96231b3b80d8		2007-11-03 07:20:12 +00:00
..
Alpha
ARM	Fix memcpy lowering when addresses are 4-byte aligned but size is not multiple of 4.	2007-10-22 22:11:27 +00:00
CBackend
Generic	-pre-RA-sched=none, simple, simple-noitin are gone.	2007-10-01 22:17:20 +00:00
IA64
PowerPC	On second thought. Remove this as it should never be generated in the first	2007-10-26 20:34:37 +00:00
SPARC
X86	There are times when the coalescer would not coalesce away a copy but the copy	2007-11-03 07:20:12 +00:00