Commit Graph

18 Commits

Author SHA1 Message Date
Juergen Ributzka
943ce55f39 Revert "Revert "Add Constant Hoisting Pass" (r200034)"
This reverts commit r200058 and adds the using directive for
ARMTargetTransformInfo to silence two g++ overload warnings.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200062 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-25 02:02:55 +00:00
Hans Wennborg
503793e834 Revert "Add Constant Hoisting Pass" (r200034)
This commit caused -Woverloaded-virtual warnings. The two new
TargetTransformInfo::getIntImmCost functions were only added to the superclass,
and to the X86 subclass. The other targets were not updated, and the
warning highlighted this by pointing out that e.g. ARMTTI::getIntImmCost was
hiding the two new getIntImmCost variants.

We could pacify the warning by adding "using TargetTransformInfo::getIntImmCost"
to the various subclasses, or turning it off, but I suspect that it's wrong to
leave the functions unimplemnted in those targets. The default implementations
return TCC_Free, which I don't think is right e.g. for ARM.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200058 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-25 01:18:18 +00:00
Juergen Ributzka
96172cb4a4 Add Constant Hoisting Pass
Retry commit r200022 with a fix for the build bot errors. Constant expressions
have (unlike instructions) module scope use lists and therefore may have users
in different functions. The fix is to simply ignore these out-of-function uses.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200034 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-24 20:18:00 +00:00
Juergen Ributzka
dc6f9b9a4f Revert "Add Constant Hoisting Pass"
This reverts commit r200022 to unbreak the build bots.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200024 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-24 18:40:30 +00:00
Juergen Ributzka
fb282c68b7 Add Constant Hoisting Pass
This pass identifies expensive constants to hoist and coalesces them to
better prepare it for SelectionDAG-based code generation. This works around the
limitations of the basic-block-at-a-time approach.

First it scans all instructions for integer constants and calculates its
cost. If the constant can be folded into the instruction (the cost is
TCC_Free) or the cost is just a simple operation (TCC_BASIC), then we don't
consider it expensive and leave it alone. This is the default behavior and
the default implementation of getIntImmCost will always return TCC_Free.

If the cost is more than TCC_BASIC, then the integer constant can't be folded
into the instruction and it might be beneficial to hoist the constant.
Similar constants are coalesced to reduce register pressure and
materialization code.

When a constant is hoisted, it is also hidden behind a bitcast to force it to
be live-out of the basic block. Otherwise the constant would be just
duplicated and each basic block would have its own copy in the SelectionDAG.
The SelectionDAG recognizes such constants as opaque and doesn't perform
certain transformations on them, which would create a new expensive constant.

This optimization is only applied to integer constants in instructions and
simple (this means not nested) constant cast experessions. For example:
%0 = load i64* inttoptr (i64 big_constant to i64*)

Reviewed by Eric

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200022 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-24 18:23:08 +00:00
Stephen Lin
8b2b8a1835 Mass update to CodeGen tests to use CHECK-LABEL for labels corresponding to function definitions for more informative error messages. No functionality change and all updated tests passed locally.
This update was done with the following bash script:

  find test/CodeGen -name "*.ll" | \
  while read NAME; do
    echo "$NAME"
    if ! grep -q "^; *RUN: *llc.*debug" $NAME; then
      TEMP=`mktemp -t temp`
      cp $NAME $TEMP
      sed -n "s/^define [^@]*@\([A-Za-z0-9_]*\)(.*$/\1/p" < $NAME | \
      while read FUNC; do
        sed -i '' "s/;\(.*\)\([A-Za-z0-9_-]*\):\( *\)$FUNC: *\$/;\1\2-LABEL:\3$FUNC:/g" $TEMP
      done
      sed -i '' "s/;\(.*\)-LABEL-LABEL:/;\1-LABEL:/" $TEMP
      sed -i '' "s/;\(.*\)-NEXT-LABEL:/;\1-NEXT:/" $TEMP
      sed -i '' "s/;\(.*\)-NOT-LABEL:/;\1-NOT:/" $TEMP
      sed -i '' "s/;\(.*\)-DAG-LABEL:/;\1-DAG:/" $TEMP
      mv $TEMP $NAME
    fi
  done


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186280 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-14 06:24:09 +00:00
Evan Cheng
376642ed62 Some enhancements for memcpy / memset inline expansion.
1. Teach it to use overlapping unaligned load / store to copy / set the trailing
   bytes. e.g. On 86, use two pairs of movups / movaps for 17 - 31 byte copies.
2. Use f64 for memcpy / memset on targets where i64 is not legal but f64 is. e.g.
   x86 and ARM.
3. When memcpy from a constant string, do *not* replace the load with a constant
   if it's not possible to materialize an integer immediate with a single
   instruction (required a new target hook: TLI.isIntImmLegal()).
4. Use unaligned load / stores more aggressively if target hooks indicates they
   are "fast".
5. Update ARM target hooks to use unaligned load / stores. e.g. vld1.8 / vst1.8.
   Also increase the threshold to something reasonable (8 for memset, 4 pairs
   for memcpy).

This significantly improves Dhrystone, up to 50% on ARM iOS devices.

rdar://12760078


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169791 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-10 23:21:26 +00:00
Jakob Stoklund Olesen
4a9b615f3e Delete stale comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@144542 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-14 18:03:05 +00:00
Jakob Stoklund Olesen
56ad83d47c RAGreedy is better about hinting now.
Or maybe we are just getting lucky.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@144473 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-12 22:39:37 +00:00
Chris Lattner
b85e4eba85 rip out a ton of intrinsic modernization logic from AutoUpgrade.cpp, which is
for pre-2.9 bitcode files.  We keep x86 unaligned loads, movnt, crc32, and the
target indep prefetch change.

As usual, updating the testsuite is a PITA.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133337 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-18 06:05:24 +00:00
Andrew Trick
87896d9368 Recommit r129383. PreRA scheduler heuristic fixes: VRegCycle, TokenFactor latency.
Additional fixes:
Do something reasonable for subtargets with generic
itineraries by handle node latency the same as for an empty
itinerary. Now nodes default to unit latency unless an itinerary
explicitly specifies a zero cycle stage or it is a TokenFactor chain.

Original fixes:
UnitsSharePred was a source of randomness in the scheduler: node
priority depended on the queue data structure. I rewrote the recent
VRegCycle heuristics to completely replace the old heuristic without
any randomness. To make the ndoe latency adjustments work, I also
needed to do something a little more reasonable with TokenFactor. I
gave it zero latency to its consumers and always schedule it as low as
possible.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129421 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-13 00:38:32 +00:00
Andrew Trick
c558bf3972 Revert 129383. It causes some targets to hit a scheduler assert.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129385 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-12 20:14:07 +00:00
Andrew Trick
3eb4319313 PreRA scheduler heuristic fixes: VRegCycle, TokenFactor latency.
UnitsSharePred was a source of randomness in the scheduler: node
priority depended on the queue data structure. I rewrote the recent
VRegCycle heuristics to completely replace the old heuristic without
any randomness. To make these heuristic adjustments to node latency work,
I also needed to do something a little more reasonable with TokenFactor. I
gave it zero latency to its consumers and always schedule it as low as
possible.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129383 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-12 19:54:36 +00:00
Jakob Stoklund Olesen
ca6fd009ad Fix ARM tests to be register allocator independent.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128680 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-31 22:14:03 +00:00
Dan Gohman
fce288fc91 Eliminate more uses of llvm-as and llvm-dis.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81293 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-09 00:09:15 +00:00
Evan Cheng
925492279a Changing allocation ordering from r3 ... r0 back to r0 ... r3. The order change no longer make sense after the coalescing changes we have made since then.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72955 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-05 19:08:58 +00:00
Evan Cheng
f0e366a929 Fix PR3457: Ignore control successors when looking for closest scheduled successor. A control successor doesn't read result(s) produced by the scheduling unit being evaluated.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64210 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-10 08:30:11 +00:00
Evan Cheng
4102eb57bb Fix memcpy lowering when addresses are 4-byte aligned but size is not multiple of 4.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@43234 91177308-0d34-0410-b5e6-96231b3b80d8
2007-10-22 22:11:27 +00:00