10 Commits

Author SHA1 Message Date
Justin Lebar
34292bd5ac [ValueTracking] Implement SignBitMustBeZero correctly for sqrt.
Summary:
Previously we assumed that the result of sqrt(x) always had 0 as its
sign bit.  But sqrt(-0) == -0.

Reviewers: hfinkel, efriedma, sanjoy

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D28928

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293115 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-26 00:10:26 +00:00
Matt Arsenault
1f4353fb62 InstSimplify: Eliminate fabs on known positive
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291624 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-11 00:33:24 +00:00
Zia Ansari
ea5455c788 [InstSimplify] Add "X / 1.0" to SimplifyFDivInst.
Differential Revision: https://reviews.llvm.org/D27587


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289153 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-08 23:27:40 +00:00
Sanjay Patel
328a9cb5c6 [InstSimplify] add fdiv x/1.0 test and update checks; NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289098 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-08 20:23:56 +00:00
Sanjay Patel
89e202e5fa [InstSimplify] regenerate checks using a script
I didn't notice any significant changes in the actual checks here;
all of these tests already used FileCheck, so a script can batch
update them in one shot.

This commit is just to show the value of automating this process: 
We have uniform formatting as opposed to a mish-mash of check
structure that changes based on individual prefs and the current
fashion. This makes it simpler to update when we find a bug or
make an enhancement.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@264457 91177308-0d34-0410-b5e6-96231b3b80d8
2016-03-25 20:12:25 +00:00
Benjamin Kramer
e8af9d944e [InstSimplify] fsub 0.0, (fsub -0.0, X) ==> X is only safe if signed zeros are ignored.
Only allow fsub -0.0, (fsub -0.0, X) ==> X without nsz. PR26746.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@262212 91177308-0d34-0410-b5e6-96231b3b80d8
2016-02-29 11:12:23 +00:00
Sanjay Patel
d2c64e2df9 Fix really obscure bug in CannotBeNegativeZero() (PR22688)
With a diabolically crafted test case, we could recurse
through this code and return true instead of false.

The larger engineering crime is the use of magic numbers. 
Added FIXME comments for those.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230515 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-25 18:00:15 +00:00
Stephen Lin
39f4e8d9cc Update Transforms tests to use CHECK-LABEL for easier debugging. No functionality change.
This update was done with the following bash script:

  find test/Transforms -name "*.ll" | \
  while read NAME; do
    echo "$NAME"
    if ! grep -q "^; *RUN: *llc" $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
      mv $TEMP $NAME
    fi
  done


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186268 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-14 01:42:54 +00:00
Benjamin Kramer
8e708d30a3 Add missing colons to check lines.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179277 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-11 12:41:41 +00:00
Michael Ilseman
09ee250e72 Added a slew of SimplifyInstruction floating-point optimizations, many of which take advantage of fast-math flags. Test cases included.
fsub X, +0 ==> X
  fsub X, -0 ==> X, when we know X is not -0
  fsub +/-0.0, (fsub -0.0, X) ==> X
  fsub nsz +/-0.0, (fsub +/-0.0, X) ==> X
  fsub nnan ninf X, X ==> 0.0
  fadd nsz X, 0 ==> X
  fadd [nnan ninf] X, (fsub [nnan ninf] 0, X) ==> 0
    where nnan and ninf have to occur at least once somewhere in this expression
  fmul X, 1.0 ==> X



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169940 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-12 00:27:46 +00:00