Commit Graph

22 Commits

Author SHA1 Message Date
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
Piotr Padlewski 5b3db45e8f Implement strip.invariant.group
Summary:
This patch introduce new intrinsic -
strip.invariant.group that was described in the
RFC: Devirtualization v2

Reviewers: rsmith, hfinkel, nlopes, sanjoy, amharc, kuhar

Subscribers: arsenm, nhaehnle, JDevlieghere, hiraditya, xbolva00, llvm-commits

Differential Revision: https://reviews.llvm.org/D47103

Co-authored-by: Krzysztof Pszeniczny <krzysztof.pszeniczny@gmail.com>
llvm-svn: 336073
2018-07-02 04:49:30 +00:00
Piotr Padlewski e9832dfdf3 [CaptureTracking] Handle capturing of launder.invariant.group
Summary:
launder.invariant.group has the same rules of capturing as
bitcast, gep, etc - the original value is not captured
if the returned pointer is not captured.

With this patch, we mark 40% more functions as noalias when compiling with -fstrict-vtable-pointers;
1078 vs 1778  (39.37%)

Reviewers: sanjoy, davide, nlewycky, majnemer, mehdi_amini

Subscribers: JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D32673

llvm-svn: 331587
2018-05-05 10:23:27 +00:00
Fedor Sergeev 6660fd0f95 [PM][FunctionAttrs] add NoUnwind attribute inference to PostOrderFunctionAttrs pass
Summary:
This was motivated by absence of PrunEH functionality in new PM.
It was decided that a proper way to do PruneEH is to add NoUnwind inference
into PostOrderFunctionAttrs and then perform normal SimplifyCFG on top.

This change generalizes attribute handling implemented for (a removal of)
Convergent attribute, by introducing a generic builder-like class
   AttributeInferer

It registers all the attribute inference requests, storing per-attribute
predicates into a vector, and then goes through an SCC Node, scanning all
the instructions for not breaking attribute assumptions.

The main idea is that as soon all the instructions from all the functions
of SCC Node conform to attribute assumptions then we are free to infer
the attribute as set for all the functions of SCC Node.

It handles two distinct cases of attributes:
   - those that might break due to derefinement of the function code

     for these attributes we are allowed to apply inference only if all the
     functions are "exact definitions". Example - NoUnwind.

   - those that do not care about derefinement

     for these attributes we are allowed to apply inference as soon as we see
     any function definition. Example - removal of Convergent attribute.

Also in this commit:
* Converted all the FunctionAttrs tests to use FileCheck and added new-PM
  invocations to them

* FunctionAttrs/convergent.ll test demonstrates a difference in behavior between
   new and old PM implementations. Marked with FIXME.

* PruneEH tests were converted to new-PM as well, using function-attrs+simplify-cfg
  combo as intended

* some of "other" tests were updated since function-attrs now infers 'nounwind'
  even for old PM pipeline

* -disable-nounwind-inference hidden option added as a possible workaround for a supposedly
  rare case when nounwind being inferred by default presents a problem

Reviewers: chandlerc, jlebar

Reviewed By: jlebar

Subscribers: eraman, llvm-commits

Differential Revision: https://reviews.llvm.org/D44415

llvm-svn: 328377
2018-03-23 21:46:16 +00:00
David Majnemer 5246e0b2c2 [FunctionAttrs] Correct the safety analysis for inference of 'returned'
We skipped over ReturnInsts which didn't return an argument which would
lead us to incorrectly conclude that an argument returned by another
ReturnInst was 'returned'.

This reverts commit r275756.

This fixes PR28610.

llvm-svn: 276008
2016-07-19 18:50:26 +00:00
NAKAMURA Takumi 966bde50c3 Revert r275678, "Revert "Revert r275027 - Let FuncAttrs infer the 'returned' argument attribute""
This reverts also r275029, "Update Clang tests after adding inference for the returned argument attribute"

It broke LTO build. Seems miscompilation.

llvm-svn: 275756
2016-07-18 03:23:25 +00:00
Hal Finkel 660096b260 Revert "Revert r275027 - Let FuncAttrs infer the 'returned' argument attribute"
This reverts commit r275042; the initial commit triggered self-hosting failures
on ARM/AArch64. James Molloy identified the problematic backend code, which has
been disabled in r275677. Trying again...

Original commit message:

Let FuncAttrs infer the 'returned' argument attribute

A function can have one argument with the 'returned' attribute, indicating that
the associated argument is always the return value of the function. Add
FuncAttrs inference logic.

llvm-svn: 275678
2016-07-16 07:21:28 +00:00
Hal Finkel 02012bcfee Revert r275027 - Let FuncAttrs infer the 'returned' argument attribute
Reverting r275027 and r275033. These seem to cause miscompiles on the AArch64 buildbot.

llvm-svn: 275042
2016-07-11 04:51:23 +00:00
Hal Finkel d66a7b05db Let FuncAttrs infer the 'returned' argument attribute
A function can have one argument with the 'returned' attribute, indicating that
the associated argument is always the return value of the function. Add
FuncAttrs inference logic.

Differential Revision: http://reviews.llvm.org/D22202

llvm-svn: 275027
2016-07-10 22:02:55 +00:00
David Majnemer 7f32420ed5 [CaptureTracking] Volatile operations capture their memory location
The memory location that corresponds to a volatile operation is very
special.  They are observed by the machine in ways which we cannot
reason about.

Differential Revision: http://reviews.llvm.org/D20555

llvm-svn: 270879
2016-05-26 17:36:22 +00:00
Philip Reames 36706852d3 [CaptureTracking] Add a test case for pointer cmpxchg
This test builds on 261250 (IR support for cmpxchg of pointers) and 261245 (capture tracking support for cmpxchg) to show that correctly analyze the capturing of pointers in a cmpxchg of pointer type.

llvm-svn: 261284
2016-02-19 00:13:09 +00:00
Philip Reames bd09e86f82 [CaptureTracking] Support atomicrmw and cmpxchg
These atomic operations are conceptually both a load and store from the same location. As such, we can treat them as the most conservative of those two components which in practice, means we can treat them like stores. An cmpxchg or atomicrmw captures the values, but not the locations accessed.

Note: We can probably be more aggressive about the comparison value in an cmpxhg since to have it be in memory, it must already be captured, but I figured it was better to avoid that for the moment.

Note 2: It turns out that since we don't actually support cmpxchg of pointer type, writing a negative test is impossible.

Differential Revision: http://reviews.llvm.org/D17400

llvm-svn: 261245
2016-02-18 19:23:27 +00:00
David Majnemer 7fddeccb8b Move the personality function from LandingPadInst to Function
The personality routine currently lives in the LandingPadInst.

This isn't desirable because:
- All LandingPadInsts in the same function must have the same
  personality routine.  This means that each LandingPadInst beyond the
  first has an operand which produces no additional information.

- There is ongoing work to introduce EH IR constructs other than
  LandingPadInst.  Moving the personality routine off of any one
  particular Instruction and onto the parent function seems a lot better
  than have N different places a personality function can sneak onto an
  exceptional function.

Differential Revision: http://reviews.llvm.org/D10429

llvm-svn: 239940
2015-06-17 20:52:32 +00:00
David Blaikie 23af64846f [opaque pointer type] Add textual IR support for explicit type parameter to the call instruction
See r230786 and r230794 for similar changes to gep and load
respectively.

Call is a bit different because it often doesn't have a single explicit
type - usually the type is deduced from the arguments, and just the
return type is explicit. In those cases there's no need to change the
IR.

When that's not the case, the IR usually contains the pointer type of
the first operand - but since typed pointers are going away, that
representation is insufficient so I'm just stripping the "pointerness"
of the explicit type away.

This does make the IR a bit weird - it /sort of/ reads like the type of
the first operand: "call void () %x(" but %x is actually of type "void
()*" and will eventually be just of type "ptr". But this seems not too
bad and I don't think it would benefit from repeating the type
("void (), void () * %x(" and then eventually "void (), ptr %x(") as has
been done with gep and load.

This also has a side benefit: since the explicit type is no longer a
pointer, there's no ambiguity between an explicit type and a function
that returns a function pointer. Previously this case needed an explicit
type (eg: a function returning a void() function was written as
"call void () () * @x(" rather than "call void () * @x(" because of the
ambiguity between a function returning a pointer to a void() function
and a function returning void).

No ambiguity means even function pointer return types can just be
written alone, without writing the whole function's type.

This leaves /only/ the varargs case where the explicit type is required.

Given the special type syntax in call instructions, the regex-fu used
for migration was a bit more involved in its own unique way (as every
one of these is) so here it is. Use it in conjunction with the apply.sh
script and associated find/xargs commands I've provided in rr230786 to
migrate your out of tree tests. Do let me know if any of this doesn't
cover your cases & we can iterate on a more general script/regexes to
help others with out of tree tests.

About 9 test cases couldn't be automatically migrated - half of those
were functions returning function pointers, where I just had to manually
delete the function argument types now that we didn't need an explicit
function type there. The other half were typedefs of function types used
in calls - just had to manually drop the * from those.

import fileinput
import sys
import re

pat = re.compile(r'((?:=|:|^|\s)call\s(?:[^@]*?))(\s*$|\s*(?:(?:\[\[[a-zA-Z0-9_]+\]\]|[@%](?:(")?[\\\?@a-zA-Z0-9_.]*?(?(3)"|)|{{.*}}))(?:\(|$)|undef|inttoptr|bitcast|null|asm).*$)')
addrspace_end = re.compile(r"addrspace\(\d+\)\s*\*$")
func_end = re.compile("(?:void.*|\)\s*)\*$")

def conv(match, line):
  if not match or re.search(addrspace_end, match.group(1)) or not re.search(func_end, match.group(1)):
    return line
  return line[:match.start()] + match.group(1)[:match.group(1).rfind('*')].rstrip() + match.group(2) + line[match.end():]

for line in sys.stdin:
  sys.stdout.write(conv(re.search(pat, line), line))

llvm-svn: 235145
2015-04-16 23:24:18 +00:00
David Blaikie a79ac14fa6 [opaque pointer type] Add textual IR support for explicit type parameter to load instruction
Essentially the same as the GEP change in r230786.

A similar migration script can be used to update test cases, though a few more
test case improvements/changes were required this time around: (r229269-r229278)

import fileinput
import sys
import re

pat = re.compile(r"((?:=|:|^)\s*load (?:atomic )?(?:volatile )?(.*?))(| addrspace\(\d+\) *)\*($| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$)")

for line in sys.stdin:
  sys.stdout.write(re.sub(pat, r"\1, \2\3*\4", line))

Reviewers: rafael, dexonsmith, grosser

Differential Revision: http://reviews.llvm.org/D7649

llvm-svn: 230794
2015-02-27 21:17:42 +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
Nick Lewycky 59633cb478 When analyzing params/args for readnone/readonly, don't forget to consider that a pointer argument may be passed through a callsite to the return, and that we may need to analyze it. Fixes a bug reported on llvm-dev: http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-May/073098.html
llvm-svn: 209870
2014-05-30 02:31:27 +00:00
Matt Arsenault e55a2c2e6b Make nocapture analysis work with addrspacecast
llvm-svn: 199246
2014-01-14 19:11:52 +00:00
Nick Lewycky c2ec0725ce Extend 'readonly' and 'readnone' to work on function arguments as well as
functions. Make the function attributes pass add it to known library functions
and when it can deduce it.

llvm-svn: 185735
2013-07-06 00:29:58 +00:00
Nick Lewycky 4c378a4453 Change CaptureTracking to pass a Use* instead of a Value* when a value is
captured. This allows the tracker to look at the specific use, which may be
especially interesting for function calls.

Use this to fix 'nocapture' deduction in FunctionAttrs. The existing one does
not iterate until a fixpoint and does not guarantee that it produces the same
result regardless of iteration order. The new implementation builds up a graph
of how arguments are passed from function to function, and uses a bottom-up walk
on the argument-SCCs to assign nocapture. This gets us nocapture more often, and
does so rather efficiently and independent of iteration order.

llvm-svn: 147327
2011-12-28 23:24:21 +00:00
Nick Lewycky 854c869c36 Move this test from date-name to feature-name, and port it to FileCheck.
llvm-svn: 147223
2011-12-23 18:41:31 +00:00