19 Commits

Author SHA1 Message Date
Sanjay Patel
05dbdb0088 Revert "[InstCombine] canonicalize trunc + insert as bitcast + shuffle, part 1 (2nd try)"
This reverts commit e71b81cab09bf33e3b08ed600418b72cc4117461.

As discussed in the planned follow-on to this patch (D138874),
this and the subsequent patches in this set can cause trouble for
the backend, and there's probably no quick fix. We may even
want to canonicalize in the opposite direction (towards insertelt).
2022-12-08 14:16:46 -05:00
Sanjay Patel
e71b81cab0 [InstCombine] canonicalize trunc + insert as bitcast + shuffle, part 1 (2nd try)
The first attempt was reverted because a clang test changed
unexpectedly - the file is already marked with a FIXME, so
I just updated it this time to pass.

Original commit message:
This is the main patch for converting a truncated scalar that is
inserted into a vector to bitcast+shuffle. We could go either way
on patterns like this, but this direction will allow collapsing a
pair of these sequences on the motivating example from issue

The patch is split into 3 parts to make it easier to see the
progression of tests diffs. We allow inserting/shuffling into a
different size vector for flexibility, so there are several test
variations. The length-changing is handled by shortening/padding
the shuffle mask with undef elements.

In part 1, handle the basic pattern:
inselt undef, (trunc T), IndexC --> shuffle (bitcast T), IdentityMask

Proof for the endian-dependency behaving as expected:
https://alive2.llvm.org/ce/z/BsA7yC

The TODO items for handling shifts and insert into an arbitrary base
vector value are implemented as follow-ups.

Differential Revision: https://reviews.llvm.org/D138872
2022-11-30 14:52:20 -05:00
Sanjay Patel
5eacdcff06 Revert "[InstCombine] canonicalize trunc + insert as bitcast + shuffle, part 1"
This reverts commit a4c466766db77cd1fb42d7f98f32bb87a3d38829.
This broke clang tests that are wrongly dependent on the optimizer.
2022-11-30 14:10:50 -05:00
Sanjay Patel
a4c466766d [InstCombine] canonicalize trunc + insert as bitcast + shuffle, part 1
This is the main patch for converting a truncated scalar that is
inserted into a vector to bitcast+shuffle. We could go either way
on patterns like this, but this direction will allow collapsing a
pair of these sequences on the motivating example from issue

The patch is split into 3 parts to make it easier to see the
progression of tests diffs. We allow inserting/shuffling into a
different size vector for flexibility, so there are several test
variations. The length-changing is handled by shortening/padding
the shuffle mask with undef elements.

In part 1, handle the basic pattern:
inselt undef, (trunc T), IndexC --> shuffle (bitcast T), IdentityMask

Proof for the endian-dependency behaving as expected:
https://alive2.llvm.org/ce/z/BsA7yC

The TODO items for handling shifts and insert into an arbitrary base
vector value are implemented as follow-ups.

Differential Revision: https://reviews.llvm.org/D138872
2022-11-30 13:22:04 -05:00
Bjorn Pettersson
4ab40eca08 [test][InstCombine] Update some test cases to use opaque pointers
These tests cases were converted using the script at
https://gist.github.com/nikic/98357b71fd67756b0f064c9517b62a34

Differential Revision: https://reviews.llvm.org/D135094
2022-10-03 22:17:59 +02:00
Nuno Lopes
952e069393 [NFC] remove 'br undef' from InstCombine test cases
This is UB and allows the compiler to give any result, so these tests weren't meaningful
InstCombine tests are now clean of 'br undef'
2022-06-10 15:28:57 +01:00
Bjorn Pettersson
acdc419c89 [test] Use -passes=instcombine instead of -instcombine in lots of tests. NFC
Another step moving away from the deprecated syntax of specifying
pass pipeline in opt.

Differential Revision: https://reviews.llvm.org/D119081
2022-02-07 14:26:59 +01:00
Philip Reames
e6ad9ef4e7 [instcombine] Canonicalize constant index type to i64 for extractelement/insertelement
The basic idea to this is that a) having a single canonical type makes CSE easier, and b) many of our transforms are inconsistent about which types we end up with based on visit order.

I'm restricting this to constants as for non-constants, we'd have to decide whether the simplicity was worth extra instructions. For constants, there are no extra instructions.

We chose the canonical type as i64 arbitrarily.  We might consider changing this to something else in the future if we have cause.

Differential Revision: https://reviews.llvm.org/D115387
2021-12-13 16:56:22 -08:00
Philip Reames
1a18de3d0a Autogen a bunch of instcombine and vectorizer tests
Done in advance of D115387.  These are all the ones which my local script could handle, there's a couple more which need manual updates.
2021-12-13 10:41:38 -08:00
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
Craig Topper
b5bf016015 [InstCombine] Support ~(c-X) --> X+(-c-1) and ~(X-c) --> (-c-1)-X for splat vectors.
llvm-svn: 310195
2017-08-06 06:28:41 +00:00
Sanjay Patel
e12d734be3 [InstCombine] narrow truncated add/sub/mul with constant
Name: narrow_sub
  %sub = sub i32 C1, %x
  %r = trunc i32 %sub to i8
  =>  
  %xn = trunc i32 %x to i8
  %narrowC = trunc i32 C1 to i8
  %r = sub i8 %narrowC, %xn
 
Name: narrow_add
  %add = add i32 %x, C1
  %r = trunc i32 %add to i8
  =>  
  %xn = trunc i32 %x to i8
  %narrowC = trunc i32 C1 to i8
  %r = add i8 %xn, %narrowC
  
Name: narrow_mul
  %mul = mul i32 %x, C1
  %r = trunc i32 %mul to i8
  =>  
  %xn = trunc i32 %x to i8
  %narrowC = trunc i32 C1 to i8
  %r = mul i8 %xn, %narrowC


http://rise4fun.com/Alive/QpS

This doesn't solve PR34046 (failure to recognize rotate):
https://bugs.llvm.org/show_bug.cgi?id=34046
...but it reduces an extra complication in the description examples 
to a form that we can more easily match.

llvm-svn: 310141
2017-08-04 22:30:34 +00:00
Michael Kuperstein
a0c6ae02a5 [InstCombine] scalarizePHI should not assume the code it sees has been CSE'd
scalarizePHI only looked for phis that have exactly two uses - the "latch"
use, and an extract. Unfortunately, we can not assume all equivalent extracts
are CSE'd, since InstCombine itself may create an extract which is a duplicate
of an existing one. This extends it to handle several distinct extracts from
the same index.

This should fix at least some of the  performance regressions from PR27988.

Differential Revision: http://reviews.llvm.org/D20983

llvm-svn: 271961
2016-06-06 23:38:33 +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
72196f3ae5 InstCombine: Teach most integer add/sub/mul/div combines how to deal with vectors.
llvm-svn: 199602
2014-01-19 15:24:22 +00:00
Benjamin Kramer
c10563d14e Fix broken CHECK lines.
llvm-svn: 199016
2014-01-11 21:06:00 +00:00
Joey Gouly
83699284be scalarizePHI needs to insert the next ExtractElement in the same block
as the BinaryOperator, *not* in the block where the IRBuilder is currently
inserting into. Fixes a bug where scalarizePHI would create instructions
that would not dominate all uses.

llvm-svn: 182639
2013-05-24 12:29:54 +00:00
Anat Shemer
0c95efad7e Added a function scalarizePHI() that sclarizes a vector phi instruction if it has only 2 uses: one to promote the vector phi in a loop and the other use is an extract operation of one element at a constant location.
llvm-svn: 179783
2013-04-18 19:35:39 +00:00