Commit Graph

14 Commits

Author SHA1 Message Date
Roman Lebedev a2dd672c5f [NFC][InstCombine] Autogenerate a few tests
llvm-svn: 366643
2019-07-20 21:34:00 +00:00
Eric Christopher cee313d288 Revert "Temporarily Revert "Add basic loop fusion pass.""
The reversion apparently deleted the test/Transforms directory.

Will be re-reverting again.

llvm-svn: 358552
2019-04-17 04:52:47 +00:00
Eric Christopher a863435128 Temporarily Revert "Add basic loop fusion pass."
As it's causing some bot failures (and per request from kbarton).

This reverts commit r358543/ab70da07286e618016e78247e4a24fcb84077fda.

llvm-svn: 358546
2019-04-17 02:12:23 +00:00
Sanjoy Das 6f1937b10f [InstCombine] Simplify Add with remainder expressions as operands.
Summary:
Simplify integer add expression X % C0 + (( X / C0 ) % C1) * C0 to
X % (C0 * C1).  This is a common pattern seen in code generated by the XLA
GPU backend.

Add test cases for this new optimization.

Patch by Bixia Zheng!

Reviewers: sanjoy

Reviewed By: sanjoy

Subscribers: efriedma, craig.topper, lebedev.ri, llvm-commits, jlebar

Differential Revision: https://reviews.llvm.org/D45976

llvm-svn: 330992
2018-04-26 20:52:28 +00:00
Sanjoy Das 0e643db48f Add test cases to prepare for the optimization that simplifies Add with
remainder expressions as operands.

Summary:
Add test cases to prepare for the new optimization that Simplifies integer add
expression X % C0 + (( X / C0 ) % C1) * C0 to X % (C0 * C1).

Patch by Bixia Zheng!

Reviewers: sanjoy

Reviewed By: sanjoy

Subscribers: jlebar, llvm-commits

Differential Revision: https://reviews.llvm.org/D46017

llvm-svn: 330991
2018-04-26 20:52:27 +00:00
Owen Anderson a4428aa484 Remove an InstCombine that transformed patterns like (x * uitofp i1 y) to (select y, x, 0.0) when the multiply has fast math flags set.
While this might seem like an obvious canonicalization, there is one subtle problem with it.  The result of the original expression
is undef when x is NaN (remember, fast math flags), but the result of the select is always defined when x is NaN.  This means that the
new expression is strictly more defined than the original one.  One unfortunate consequence of this is that the transform is not reversible!
It's always legal to make increase the defined-ness of an expression, but it's not legal to reduce it.  Thus, targets that prefer the original
form of the expression cannot reverse the transform to recover it.  Another way to think of it is that the transform has lost source-level
information (the fast math flags), which is undesirable.

llvm-svn: 215825
2014-08-17 03:51:29 +00:00
Benjamin Kramer 76b15d04ff InstCombine: Refactor fmul/fdiv combines to handle vectors.
llvm-svn: 199598
2014-01-19 13:36:27 +00:00
Stephen Lin 03f9fbbcd7 Restore r181216, which was partially reverted in r182499.
llvm-svn: 186533
2013-07-17 20:06:03 +00:00
Stephen Lin c1c7a1309c 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

llvm-svn: 186268
2013-07-14 01:42:54 +00:00
Jean-Luc Duprat 0dda6f168c This is an update to a previous commit (r181216).
The earlier change list introduced the following inst combines:
B * (uitofp i1 C) —> select C, B, 0
A * (1 - uitofp i1 C) —> select C, 0, A
select C, 0, B + select C, A, 0 —> select C, A, B

Together these 3 changes would simplify :
A * (1 - uitofp i1 C) + B * uitofp i1 C 
down to :
select C, B, A

In practice we found that the first two substitutions can have a
negative effect on performance, because they reduce opportunities to
use FMA contractions; between the two options FMAs are often the
better choice.  This change list amends the previous one to enable
just these inst combines:

select C, B, 0 + select C, 0, A —> select C, B, A
A * (1 - uitofp i1 C) + B * uitofp i1 C —> select C, B, A

llvm-svn: 182499
2013-05-22 18:29:31 +00:00
Benjamin Kramer a6645e8b8f InstCombine: Verify the type before transforming uitofp into select.
PR15952.

llvm-svn: 181586
2013-05-10 09:16:52 +00:00
Jean-Luc Duprat 1610d571db Test results verified using FileCheck rather than grep | count
llvm-svn: 181234
2013-05-06 18:45:16 +00:00
Jean-Luc Duprat 4189ef456a Fix add4.ll test cmdline so that it passes
llvm-svn: 181219
2013-05-06 17:18:47 +00:00
Jean-Luc Duprat 3e4fc3ef24 Provide InstCombines for the following 3 cases:
A * (1 - (uitofp i1 C)) -> select C, 0, A
B * (uitofp i1 C) -> select C, B, 0
select C, 0, A + select C, B, 0 -> select C, B, A

These come up in code that has been hand-optimized from a select to a linear blend, 
on platforms where that may have mattered. We want to undo such changes 
with the following transform:
A*(1 - uitofp i1 C) + B*(uitofp i1 C) -> select C, A, B

llvm-svn: 181216
2013-05-06 16:55:50 +00:00