Commit Graph

34 Commits

Author SHA1 Message Date
Roman Lebedev 5a663bd77a [InstSimplify] Fix addo/subo undef folds (PR42209)
Fix folds of addo and subo with an undef operand to be:

`@llvm.{u,s}{add,sub}.with.overflow` all fold to `{ undef, false }`,
 as per LLVM undef rules.
Same for commuted variants.

Based on the original version of the patch by @nikic.

Fixes [[ https://bugs.llvm.org/show_bug.cgi?id=42209 | PR42209 ]]

Differential Revision: https://reviews.llvm.org/D63065

llvm-svn: 363522
2019-06-16 20:39:45 +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
Sanjay Patel 9dada83d6c [InstSimplify] remove zero-shift-guard fold for general funnel shift
As discussed on llvm-dev:
http://lists.llvm.org/pipermail/llvm-dev/2019-February/130491.html

We can't remove the compare+select in the general case because
we are treating funnel shift like a standard instruction (as
opposed to a special instruction like select/phi).

That means that if one of the operands of the funnel shift is
poison, the result is poison regardless of whether we know that
the operand is actually unused based on the instruction's
particular semantics.

The motivating case for this transform is the more specific
rotate op (rather than funnel shift), and we are preserving the
fold for that case because there is no chance of introducing
extra poison when there is no anonymous extra operand to the
funnel shift.

llvm-svn: 354905
2019-02-26 18:26:56 +00:00
Sanjay Patel 421c6e6864 [InstSimplify] add tests for rotate; NFC
Rotate is a special-case of funnel shift that has different
poison constraints than the general case. That's not visible
yet in the existing tests, but it needs to be corrected.

llvm-svn: 354894
2019-02-26 16:44:08 +00:00
Nikita Popov f17421e595 [ConstantFolding] Consolidate and extend bitcount intrinsic tests; NFC
Move constant folding tests into ConstantFolding/bitcount.ll and drop
various tests in other places. Add coverage for undefs.

llvm-svn: 349806
2018-12-20 19:46:52 +00:00
Sanjay Patel 14ab9170b8 [InstSimplify] fold funnel shifts with undef operands
Splitting these off from the D54666.

Patch by: nikic (Nikita Popov)

llvm-svn: 347332
2018-11-20 17:34:59 +00:00
Sanjay Patel 2778f56a40 [InstSimplify] add tests for funnel shift with undef operands; NFC
These are part of D54666, so adding them here before the patch to
show the baseline (currently unoptimized) results.

Patch by: @nikic (Nikita Popov)

llvm-svn: 347331
2018-11-20 17:30:09 +00:00
Sanjay Patel e98ec77a95 [InstSimplify] delete shift-of-zero guard ops around funnel shifts
This is a problem seen in common rotate idioms as noted in:
https://bugs.llvm.org/show_bug.cgi?id=34924

Note that we are not canonicalizing standard IR (shifts and logic) to the intrinsics yet. 
(Although I've written this before...) I think this is the last step before we enable 
that transform. Ie, we could regress code by doing that transform without this 
simplification in place.

In PR34924, I questioned whether this is a valid transform for target-independent IR, 
but I convinced myself this is ok. If we're speculating a funnel shift by turning cmp+br 
into select, then SimplifyCFG has already determined that the transform is justified. 
It's possible that SimplifyCFG is not taking into account profile or other metadata, 
but if that's true, then it's a bug independent of funnel shifts.

Also, we do have CGP code to restore a guard like this around an intrinsic if it can't 
be lowered cheaply. But that isn't necessary for funnel shift because the default 
expansion in SelectionDAGBuilder includes this same cmp+select.

Differential Revision: https://reviews.llvm.org/D54552

llvm-svn: 346960
2018-11-15 14:53:37 +00:00
Sanjay Patel 4832ffee39 [InstSimplify] add more tests for funnel shift with select; NFC
The cases are just different enough that we should have 
complete tests to avoid bugs from typos in the code.

llvm-svn: 346902
2018-11-14 22:34:25 +00:00
Sanjay Patel 7d028670f6 [InstSimplify] add tests for funnel shift with select; NFC
llvm-svn: 346881
2018-11-14 19:12:54 +00:00
Sanjay Patel 54421ce918 [InstSimplify] fold funnel shifts with 0-shift amount
llvm-svn: 338218
2018-07-29 16:36:38 +00:00
Sanjay Patel 46af5835af [InstSimplify] add tests for funnel shift intrinsics; NFC
llvm-svn: 338217
2018-07-29 16:27:17 +00:00
Matt Arsenault 3ced3d90c3 InstSimplify: canonicalize is idempotent
llvm-svn: 312685
2017-09-07 01:21:43 +00:00
Craig Topper fe9ad82e44 [ConstantFolding] Properly support constant folding of vector powi intrinsic. The second argument is not a vector so needs special treatment.
llvm-svn: 304679
2017-06-04 07:30:28 +00:00
Craig Topper 97f113e795 [InstSimplify] Add test case demonstrating that we fail to constant fold vector llvm.powi intrinsics due to the second argument not being a vector.
llvm-svn: 304678
2017-06-04 07:30:23 +00:00
Craig Topper 7c553edced [ConstantFolding] Fix constant folding for vector cttz and ctlz intrinsics to understand that the second argument is still a scalar.
llvm-svn: 304668
2017-06-03 18:50:29 +00:00
Craig Topper 36fa2f0dee [InstCombine][InstSimplify] Add various tests for ctlz/cttz with vectors, some showing missed optimizations. NFC
llvm-svn: 304667
2017-06-03 18:50:26 +00:00
Craig Topper 77e07cc010 [InstSimplify] Simplify uadd/sadd/umul/smul with overflow intrinsics when the Zero or Undef is on the LHS.
Summary: This code was migrated from InstCombine a few years ago. InstCombine had nearby code that would move Constants to the RHS for these, but InstSimplify doesn't have such code on this path.

Reviewers: spatel, majnemer, davide

Reviewed By: spatel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D33473

llvm-svn: 303774
2017-05-24 17:05:28 +00:00
Craig Topper ae292aaad1 [InstSimplify] Add more tests for undef inputs and multiplying by 0 for the add/sub/mul with overflow intrinsics. NFC
llvm-svn: 303671
2017-05-23 18:42:58 +00:00
Craig Topper 15288da293 [InstSimplify] auto-generate test checks. NFC
llvm-svn: 303664
2017-05-23 17:57:36 +00:00
David Majnemer 17a95aaa7b Simplify llvm.masked.load w/ undef masks
We can always pick the passthru value if the mask is undef: we are
permitted to treat the mask as-if it were filled with zeros.

llvm-svn: 275379
2016-07-14 06:58:37 +00:00
David Majnemer 7f781aba97 [ConstantFolding] Fold masked loads
We can constant fold a masked load if the operands are appropriately
constant.

Differential Revision: http://reviews.llvm.org/D22324

llvm-svn: 275352
2016-07-14 00:29:50 +00:00
Davide Italiano 16284df8ec [PM] Port InstSimplify to the new pass manager.
llvm-svn: 274796
2016-07-07 21:14:36 +00:00
David Majnemer bb53d23ef8 [InstSimplify] Replace calls to null with undef
Calling null is undefined behavior, we can simplify the resulting value
to undef.

llvm-svn: 273777
2016-06-25 07:37:30 +00:00
Philip Reames 2466719e44 [MemoryBuiltins] Remove isOperatorNewLike by consolidating non-null inference handling
This patch removes the isOperatorNewLike predicate since it was only being used to establish a non-null return value and we have attributes specifically for that purpose with generic handling. To keep approximate the same behaviour for existing frontends, I added the various operator new like (i.e. instances of operator new) to InferFunctionAttrs. It's not really clear to me why this isn't handled in Clang, but I didn't want to break existing code and any subtle assumptions it might have.

Once this patch is in, I'm going to start separating the isAllocLike family of predicates. These appear to be being used for a mixture of things which should be more clearly separated and documented. Today, they're being used to indicate (at least) aliasing facts, CSE-ability, and default values from an allocation site.

Differential Revision: http://reviews.llvm.org/D15820

llvm-svn: 256787
2016-01-04 22:49:23 +00:00
David Majnemer 1503258157 [InstSimplify] Handle some overflow intrinsics in InstSimplify
This change does a few things:
- Move some InstCombine transforms to InstSimplify
- Run SimplifyCall from within InstCombine::visitCallInst
- Teach InstSimplify to fold [us]mul_with_overflow(X, undef) to 0.

llvm-svn: 237995
2015-05-22 03:56:46 +00:00
David Blaikie 79e6c74981 [opaque pointer type] Add textual IR support for explicit type parameter to getelementptr instruction
One of several parallel first steps to remove the target type of pointers,
replacing them with a single opaque pointer type.

This adds an explicit type parameter to the gep instruction so that when the
first parameter becomes an opaque pointer type, the type to gep through is
still available to the instructions.

* This doesn't modify gep operators, only instructions (operators will be
  handled separately)

* Textual IR changes only. Bitcode (including upgrade) and changing the
  in-memory representation will be in separate changes.

* geps of vectors are transformed as:
    getelementptr <4 x float*> %x, ...
  ->getelementptr float, <4 x float*> %x, ...
  Then, once the opaque pointer type is introduced, this will ultimately look
  like:
    getelementptr float, <4 x ptr> %x
  with the unambiguous interpretation that it is a vector of pointers to float.

* address spaces remain on the pointer, not the type:
    getelementptr float addrspace(1)* %x
  ->getelementptr float, float addrspace(1)* %x
  Then, eventually:
    getelementptr float, ptr addrspace(1) %x

Importantly, the massive amount of test case churn has been automated by
same crappy python code. I had to manually update a few test cases that
wouldn't fit the script's model (r228970,r229196,r229197,r229198). The
python script just massages stdin and writes the result to stdout, I
then wrapped that in a shell script to handle replacing files, then
using the usual find+xargs to migrate all the files.

update.py:
import fileinput
import sys
import re

ibrep = re.compile(r"(^.*?[^%\w]getelementptr inbounds )(((?:<\d* x )?)(.*?)(| addrspace\(\d\)) *\*(|>)(?:$| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$))")
normrep = re.compile(       r"(^.*?[^%\w]getelementptr )(((?:<\d* x )?)(.*?)(| addrspace\(\d\)) *\*(|>)(?:$| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$))")

def conv(match, line):
  if not match:
    return line
  line = match.groups()[0]
  if len(match.groups()[5]) == 0:
    line += match.groups()[2]
  line += match.groups()[3]
  line += ", "
  line += match.groups()[1]
  line += "\n"
  return line

for line in sys.stdin:
  if line.find("getelementptr ") == line.find("getelementptr inbounds"):
    if line.find("getelementptr inbounds") != line.find("getelementptr inbounds ("):
      line = conv(re.match(ibrep, line), line)
  elif line.find("getelementptr ") != line.find("getelementptr ("):
    line = conv(re.match(normrep, line), line)
  sys.stdout.write(line)

apply.sh:
for name in "$@"
do
  python3 `dirname "$0"`/update.py < "$name" > "$name.tmp" && mv "$name.tmp" "$name"
  rm -f "$name.tmp"
done

The actual commands:
From llvm/src:
find test/ -name *.ll | xargs ./apply.sh
From llvm/src/tools/clang:
find test/ -name *.mm -o -name *.m -o -name *.cpp -o -name *.c | xargs -I '{}' ../../apply.sh "{}"
From llvm/src/tools/polly:
find test/ -name *.ll | xargs ./apply.sh

After that, check-all (with llvm, clang, clang-tools-extra, lld,
compiler-rt, and polly all checked out).

The extra 'rm' in the apply.sh script is due to a few files in clang's test
suite using interesting unicode stuff that my python script was throwing
exceptions on. None of those files needed to be migrated, so it seemed
sufficient to ignore those cases.

Reviewers: rafael, dexonsmith, grosser

Differential Revision: http://reviews.llvm.org/D7636

llvm-svn: 230786
2015-02-27 19:29:02 +00:00
Benjamin Kramer d59bf255d5 Verify that we don't optimize null return checks to the nothrow_t version of operator new.
llvm-svn: 191325
2013-09-24 18:37:49 +00:00
Benjamin Kramer 4d4df04353 MemoryBuiltins: Fix operator new bits.
We really don't want to optimize malloc return value checks away.

llvm-svn: 191313
2013-09-24 17:15:14 +00:00
Benjamin Kramer fd4777c046 Teach MemoryBuiltins and InstructionSimplify that operator new never returns NULL.
This is safe per C++11 18.6.1.1p3: [operator new returns] a non-null pointer to
suitably aligned storage (3.7.4), or else throw a bad_alloc exception. This
requirement is binding on a replacement version of this function.

Brings us a tiny bit closer to eliminating more vector push_backs.

llvm-svn: 191310
2013-09-24 16:37:51 +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
Michael Ilseman 5485729b9a Identify and simplify idempotent intrinsics. Test case included.
llvm-svn: 174650
2013-02-07 19:26:05 +00:00
Chandler Carruth f6182155f6 Teach instsimplify to use the constant folder where appropriate for
constant folding calls. Add the initial tests for this which show that
now instsimplify can simplify blindingly obvious code patterns expressed
with both intrinsics and library calls.

llvm-svn: 171194
2012-12-28 14:23:29 +00:00