Commit Graph

4 Commits

Author SHA1 Message Date
Dale Johannesen
9a6636b2cd Reapply 95050 with a tweak to check the register class.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95183 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-03 01:40:33 +00:00
Dale Johannesen
62a04136d5 Test revert 95050; there's a good chance it's causing
buildbot failure.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95103 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-02 18:52:56 +00:00
Dale Johannesen
5ce0ee9c09 Make local RA smarter about reusing input register of a copy
as output.  Needed for (functional) correctness in inline asm,
and should be generally beneficial.  7361612.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95050 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-02 02:08:02 +00:00
Dale Johannesen
fc49bd2447 Do better with physical reg operands (typically, from inline asm)
in local register allocator.  If a reg-reg copy has a phys reg
input and a virt reg output, and this is the last use of the phys
reg, assign the phys reg to the virt reg.  If a reg-reg copy has
a phys reg output and we need to reload its spilled input, reload
it directly into the phys reg than passing it through another reg.

Following 76208, there is sometimes no dependency between the def of
a phys reg and its use; this creates a window where that phys reg
can be used for spilling (this is true in linear scan also).  This
is bad and needs to be fixed a better way, although 76208 works too
well in practice to be reverted.  However, there should normally be
no spilling within inline asm blocks.  The patch here goes a long way
towards making this actually be true.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91485 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-16 00:29:41 +00:00