Summary:
while investigating performance degradation of imagick benchmark
there were found inefficient pattern for UINT_TO_FP conversion.
That pattern causes RAW hazard in assembly code. Specifically,
uitofp IR operator results in poor assembler :
st %i0, [%fp - 952]
ldd [%fp - 952], %f0
it stores 32-bit integer register into memory location and then
loads 64-bit floating point data from that location.
That is exactly RAW hazard case. To optimize that case it is
possible to use SPISD::ITOF and SPISD::XTOF for conversion from
integer to floating point data type and to use ISD::BITCAST to
copy from integer register into floating point register.
The fix is to write custom UINT_TO_FP pattern using SPISD::ITOF,
SPISD::XTOF, ISD::BITCAST.
Patch by Alexey Lapshin
Reviewers: fedor.sergeev, jyknight, dcederman, lero_chris
Reviewed By: jyknight
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D36875
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@318704 91177308-0d34-0410-b5e6-96231b3b80d8
The SparcV8 fneg and fabs instructions interestingly come only in a
single-float variant. Since the sign bit is always the topmost bit no
matter what size float it is, you simply operate on the high
subregister, as if it were a single float.
However, the layout of double-floats in the float registers is reversed
on little-endian CPUs, so that the high bits are in the second
subregister, rather than the first.
Thus, this expansion must check the endianness to use the correct
subregister.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@267489 91177308-0d34-0410-b5e6-96231b3b80d8
The (mostly-deprecated) SelectionDAG-based ILPListDAGScheduler scheduler
was making poor scheduling decisions, causing high register pressure and
extraneous register spills.
Switching to the newer machine scheduler generates better code -- even
without there being a machine model defined for SPARC yet.
(Actually committing the test changes too, this time, unlike r247315)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@247343 91177308-0d34-0410-b5e6-96231b3b80d8
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
This was done with the following sed invocation to catch label lines demarking function boundaries:
sed -i '' "s/^;\( *\)\([A-Z0-9_]*\):\( *\)test\([A-Za-z0-9_-]*\):\( *\)$/;\1\2-LABEL:\3test\4:\5/g" test/CodeGen/*/*.ll
which was written conservatively to avoid false positives rather than false negatives. I scanned through all the changes and everything looks correct.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186258 91177308-0d34-0410-b5e6-96231b3b80d8
