Commit Graph

7 Commits

Author SHA1 Message Date
Jim Grosbach
ffc658b056 ARM VLDR/VSTR instructions don't need a size suffix.
Canonicallize on the non-suffixed form, but continue to accept assembly that
has any correctly sized type suffix.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@144583 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-14 23:03:21 +00:00
Jakob Stoklund Olesen
2aa6b4c142 Fix more register allocation sensitive tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@134667 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-08 00:24:06 +00:00
Evan Cheng
8239daf7c8 Two sets of changes. Sorry they are intermingled.
1. Fix pre-ra scheduler so it doesn't try to push instructions above calls to
   "optimize for latency". Call instructions don't have the right latency and
   this is more likely to use introduce spills.
2. Fix if-converter cost function. For ARM, it should use instruction latencies,
   not # of micro-ops since multi-latency instructions is completely executed
   even when the predicate is false. Also, some instruction will be "slower"
   when they are predicated due to the register def becoming implicit input.
   rdar://8598427


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118135 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-03 00:45:17 +00:00
Evan Cheng
089751535d Avoiding overly aggressive latency scheduling. If the two nodes share an
operand and one of them has a single use that is a live out copy, favor the
one that is live out. Otherwise it will be difficult to eliminate the copy
if the instruction is a loop induction variable update. e.g.

BB:
sub r1, r3, #1
str r0, [r2, r3]
mov r3, r1
cmp
bne BB

=>

BB:
str r0, [r2, r3]
sub r3, r3, #1
cmp
bne BB

This fixed the recent 256.bzip2 regression.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117675 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-29 18:09:28 +00:00
Bob Wilson
7d24705f65 Change register allocation order for ARM VFP and NEON registers to put the
callee-saved registers at the end of the lists.  Also prefer to avoid using
the low registers that are in register subclasses required by certain
instructions, so that those registers will more likely be available when needed.
This change makes a huge improvement in spilling in some cases.  Thanks to
Jakob for helping me realize the problem.

Most of this patch is fixing the testsuite.  There are quite a few places
where we're checking for specific registers.  I changed those to wildcards
in places where that doesn't weaken the tests.  The spill-q.ll and
thumb2-spill-q.ll tests stopped spilling with this change, so I added a bunch
of live values to force spills on those tests.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116055 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-08 06:15:13 +00:00
Rafael Espindola
1e81966626 Remove arm_apcscc from the test files. It is the default and doing this
matches what llvm-gcc and clang now produce.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106221 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-17 15:18:27 +00:00
Jakob Stoklund Olesen
40d07bbebb Add CoalescerPair helper class.
Given a copy instruction, CoalescerPair can determine which registers to
coalesce in order to eliminate the copy. It deals with all the subreg fun to
determine a tuple (DstReg, SrcReg, SubIdx) such that:

- SrcReg is a virtual register that will disappear after coalescing.
- DstReg is a virtual or physical register whose live range will be extended.
- SubIdx is 0 when DstReg is a physical register.
- SrcReg can be joined with DstReg:SubIdx.

CoalescerPair::isCoalescable() determines if another copy instruction is
compatible with the same tuple. This fixes some NEON miscompilations where
shuffles are getting coalesced as if they were copies.

The CoalescerPair class will replace a lot of the spaghetti logic in JoinCopy
later.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@105997 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-15 16:04:21 +00:00