Commit Graph

70 Commits

Author SHA1 Message Date
Sanjoy Das
c9e3e3cbfd Don't IPO over functions that can be de-refined
Summary:
Fixes PR26774.

If you're aware of the issue, feel free to skip the "Motivation"
section and jump directly to "This patch".

Motivation:

I define "refinement" as discarding behaviors from a program that the
optimizer has license to discard.  So transforming:

```
void f(unsigned x) {
  unsigned t = 5 / x;
  (void)t;
}
```

to

```
void f(unsigned x) { }
```

is refinement, since the behavior went from "if x == 0 then undefined
else nothing" to "nothing" (the optimizer has license to discard
undefined behavior).

Refinement is a fundamental aspect of many mid-level optimizations done
by LLVM.  For instance, transforming `x == (x + 1)` to `false` also
involves refinement since the expression's value went from "if x is
`undef` then { `true` or `false` } else { `false` }" to "`false`" (by
definition, the optimizer has license to fold `undef` to any non-`undef`
value).

Unfortunately, refinement implies that the optimizer cannot assume
that the implementation of a function it can see has all of the
behavior an unoptimized or a differently optimized version of the same
function can have.  This is a problem for functions with comdat
linkage, where a function can be replaced by an unoptimized or a
differently optimized version of the same source level function.

For instance, FunctionAttrs cannot assume a comdat function is
actually `readnone` even if it does not have any loads or stores in
it; since there may have been loads and stores in the "original
function" that were refined out in the currently visible variant, and
at the link step the linker may in fact choose an implementation with
a load or a store.  As an example, consider a function that does two
atomic loads from the same memory location, and writes to memory only
if the two values are not equal.  The optimizer is allowed to refine
this function by first CSE'ing the two loads, and the folding the
comparision to always report that the two values are equal.  Such a
refined variant will look like it is `readonly`.  However, the
unoptimized version of the function can still write to memory (since
the two loads //can// result in different values), and selecting the
unoptimized version at link time will retroactively invalidate
transforms we may have done under the assumption that the function
does not write to memory.

Note: this is not just a problem with atomics or with linking
differently optimized object files.  See PR26774 for more realistic
examples that involved neither.

This patch:

This change introduces a new set of linkage types, predicated as
`GlobalValue::mayBeDerefined` that returns true if the linkage type
allows a function to be replaced by a differently optimized variant at
link time.  It then changes a set of IPO passes to bail out if they see
such a function.

Reviewers: chandlerc, hfinkel, dexonsmith, joker.eph, rnk

Subscribers: mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D18634

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265762 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-08 00:48:30 +00:00
Justin Lebar
dd68c9c6c5 [attrs] Handle convergent CallSites.
Summary:
Previously we had a notion of convergent functions but not of convergent
calls.  This is insufficient to correctly analyze calls where the target
is unknown, e.g. indirect calls.

Now a call is convergent if it targets a known-convergent function, or
if it's explicitly marked as convergent.  As usual, we can remove
convergent where we can prove that no convergent operations are
performed in the call.

Originally landed as r261544, then reverted in r261544 for (incidental)
build breakage.  Re-landed here with no changes.

Reviewers: chandlerc, jingyue

Subscribers: llvm-commits, tra, jhen, hfinkel

Differential Revision: http://reviews.llvm.org/D17739

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@263481 91177308-0d34-0410-b5e6-96231b3b80d8
2016-03-14 20:18:54 +00:00
Justin Lebar
0bbc549035 Revert "[attrs] Handle convergent CallSites."
This reverts r261544, which was causing a test failure in
Transforms/FunctionAttrs/readattrs.ll.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@261549 91177308-0d34-0410-b5e6-96231b3b80d8
2016-02-22 18:24:43 +00:00
Justin Lebar
4644890a51 [attrs] Handle convergent CallSites.
Summary:
Previously we had a notion of convergent functions but not of convergent
calls.  This is insufficient to correctly analyze calls where the target
is unknown, e.g. indirect calls.

Now a call is convergent if it targets a known-convergent function, or
if it's explicitly marked as convergent.  As usual, we can remove
convergent where we can prove that no convergent operations are
performed in the call.

Reviewers: chandlerc, jingyue

Subscribers: hfinkel, jhen, tra, llvm-commits

Differential Revision: http://reviews.llvm.org/D17317

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@261544 91177308-0d34-0410-b5e6-96231b3b80d8
2016-02-22 17:51:35 +00:00
Philip Reames
ab9a540a12 [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.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@261284 91177308-0d34-0410-b5e6-96231b3b80d8
2016-02-19 00:13:09 +00:00
Philip Reames
459d220c68 [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



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@261245 91177308-0d34-0410-b5e6-96231b3b80d8
2016-02-18 19:23:27 +00:00
Chandler Carruth
e9afeb0bd1 [PM] Port the PostOrderFunctionAttrs pass to the new pass manager and
convert one test to use this.

This is a particularly significant milestone because it required
a working per-function AA framework which can be queried over each
function from within a CGSCC transform pass (and additionally a module
analysis to be accessible). This is essentially *the* point of the
entire pass manager rewrite. A CGSCC transform is able to query for
multiple different function's analysis results. It works. The whole
thing appears to actually work and accomplish the original goal. While
we were able to hack function attrs and basic-aa to "work" in the old
pass manager, this port doesn't use any of that, it directly leverages
the new fundamental functionality.

For this to work, the CGSCC framework also has to support SCC-based
behavior analysis, etc. The only part of the CGSCC pass infrastructure
not sorted out at this point are the updates in the face of inlining and
running function passes that mutate the call graph.

The changes are pretty boring and boiler-plate. Most of the work was
factored into more focused preperatory patches. But this is what wires
it all together.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@261203 91177308-0d34-0410-b5e6-96231b3b80d8
2016-02-18 11:03:11 +00:00
Chandler Carruth
2c37b35a91 [attrs] Move the norecurse deduction to operate on the node set rather
than the SCC object, and have it scan the instruction stream directly
rather than relying on call records.

This makes the behavior of this routine consistent between libc routines
and LLVM intrinsics for libc routines. We can go and start teaching it
about those being norecurse, but we should behave the same for the
intrinsic and the libc routine rather than differently. I chatted with
James Molloy and the inconsistency doesn't seem intentional and likely
is due to intrinsic calls not being modelled in the call graph analyses.

This also fixes a bug where we would deduce norecurse on optnone
functions, when generally we try to handle optnone functions as-if they
were replaceable and thus unanalyzable.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260813 91177308-0d34-0410-b5e6-96231b3b80d8
2016-02-13 08:47:51 +00:00
Justin Lebar
c4f6eb8e3b Add convergent-removing bits to FunctionAttrs pass.
Summary:
Remove the convergent attribute on any functions which provably do not
contain or invoke any convergent functions.

After this change, we'll be able to modify clang to conservatively add
'convergent' to all functions when compiling CUDA.

Reviewers:  jingyue, joker.eph

Subscribers: llvm-commits, tra, jhen, hfinkel, resistor, chandlerc, arsenm

Differential Revision: http://reviews.llvm.org/D17013

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260319 91177308-0d34-0410-b5e6-96231b3b80d8
2016-02-09 23:03:22 +00:00
Sanjoy Das
23b546ba0d [FunctionAttrs] Fix SCC logic around operand bundles
FunctionAttrs does an "optimistic" analysis of SCCs as a unit, which
means normally it is able to disregard calls from an SCC into itself.
However, calls and invokes with operand bundles are allowed to have
memory effects not fully described by the memory effects on the call
target, so we can't be optimistic around operand-bundled calls from an
SCC into itself.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260244 91177308-0d34-0410-b5e6-96231b3b80d8
2016-02-09 18:40:40 +00:00
Chandler Carruth
e96fb9ab15 [attrs] Split the late-revisit pattern for deducing norecurse in
a top-down manner into a true top-down or RPO pass over the call graph.

There are specific patterns of function attributes, notably the
norecurse attribute, which are most effectively propagated top-down
because all they us caller information.

Walk in RPO over the call graph SCCs takes the form of a module pass run
immediately after the CGSCC pass managers postorder walk of the SCCs,
trying again to deduce norerucrse for each singular SCC in the call
graph.

This removes a very legacy pass manager specific trick of using a lazy
revisit list traversed during finalization of the CGSCC pass. There is
no analogous finalization step in the new pass manager, and a lazy
revisit list is just trying to produce an RPO iteration of the call
graph. We can do that more directly if more expensively. It seems
unlikely that this will be the expensive part of any compilation though
as we never examine the function bodies here. Even in an LTO run over
a very large module, this should be a reasonable fast set of operations
over a reasonably small working set -- the function call graph itself.

In the future, if this really is a compile time performance issue, we
can look at building support for both post order and RPO traversals
directly into a pass manager that builds and maintains the PO list of
SCCs.

Differential Revision: http://reviews.llvm.org/D15785

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@257163 91177308-0d34-0410-b5e6-96231b3b80d8
2016-01-08 10:55:52 +00:00
Chandler Carruth
d97964253e [attrs] Extract the pure inference of function attributes into
a standalone pass.

There is no call graph or even interesting analysis for this part of
function attributes -- it is literally inferring attributes based on the
target library identification. As such, we can do it using a much
simpler module pass that just walks the declarations. This can also
happen much earlier in the pass pipeline which has benefits for any
number of other passes.

In the process, I've cleaned up one particular aspect of the logic which
was necessary in order to separate the two passes cleanly. It now counts
inferred attributes independently rather than just counting all the
inferred attributes as one, and the counts are more clearly explained.

The two test cases we had for this code path are both ... woefully
inadequate and copies of each other. I've kept the superset test and
updated it. We need more testing here, but I had to pick somewhere to
stop fixing everything broken I saw here.

Differential Revision: http://reviews.llvm.org/D15676

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256466 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-27 08:41:34 +00:00
Chandler Carruth
6a1ce8ecd6 [attrs] Split off the forced attributes utility into its own pass that
is (by default) run much earlier than FuncitonAttrs proper.

This allows forcing optnone or other widely impactful attributes. It is
also a bit simpler as the force attribute behavior needs no specific
iteration order.

I've added the pass into the default module pass pipeline and LTO pass
pipeline which mirrors where function attrs itself was being run.

Differential Revision: http://reviews.llvm.org/D15668

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256465 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-27 08:13:45 +00:00
James Molloy
e30d17a4d7 [FunctionAttrs] Provide a mechanism for adding function attributes from the command line
This provides a way to force a function to have certain attributes from the command line. This can be useful when debugging or doing workload exploration, where manually editing IR is tedious or not possible (due to build systems etc).

The syntax is -force-attribute=function_name:attribute_name

All function attributes are parsed except alignstack as it requires an argument.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253550 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-19 08:49:57 +00:00
Elena Demikhovsky
741a772213 Vector of pointers in function attributes calculation
While setting function attributes we check all instructions that may access memory. For a call instruction we check all arguments. The special check is required for pointers.
I added vector-of-pointers to the call arguments types that should be checked.

Differential Revision: http://reviews.llvm.org/D14693



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253363 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-17 19:30:51 +00:00
James Molloy
29020c0a61 Revert "Revert "[FunctionAttrs] Identify norecurse functions""
This reapplies this patch, with test fixes.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@252871 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-12 10:55:20 +00:00
James Molloy
6cd07b45e1 Revert "[FunctionAttrs] Identify norecurse functions"
This reverts commit r252862. This introduced test failures and I'm reverting while I investigate how this happened.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@252863 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-12 09:05:43 +00:00
James Molloy
31d4df2fc6 [FunctionAttrs] Identify norecurse functions
A function can be marked as norecurse if:
  * The SCC to which it belongs has cardinality 1; and either
    a) It does not call any non-norecurse function. This includes self-recursion; or
    b) It only has one callsite and the function that callsite is within is marked norecurse.

a) is best propagated bottom-up and b) is best propagated top-down.

We build up the norecurse attributes bottom-up using the existing SCC pass, and mark functions with no obvious recursion (but not provably norecurse) to sweep later, top-down.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@252862 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-12 08:53:04 +00:00
Sanjoy Das
d044355f2d [FunctionAttrs] Fix an iterator wraparound bug
Summary:
This change fixes an iterator wraparound bug in
`determinePointerReadAttrs`.

Ideally, ++'ing off the `end()` of an iplist should result in a failed
assert, but currently iplist seems to silently wrap to the head of the
list on `end()++`.  This is why the bad behavior is difficult to
demonstrate.

Reviewers: chandlerc, reames

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D14350

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@252386 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-07 01:55:53 +00:00
Philip Reames
bf9ec6af48 [FunctionAttr] Infer nonnull attributes on returns
Teach FunctionAttr to infer the nonnull attribute on return values of functions which never return a potentially null value. This is done both via a conservative local analysis for the function itself and a optimistic per-SCC analysis. If no function in the SCC returns anything which could be null (other than values from other functions in the SCC), we can conclude no function returned a null pointer. Even if some function within the SCC returns a null pointer, we may be able to locally conclude that some don't.

Differential Revision: http://reviews.llvm.org/D9688



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@246476 91177308-0d34-0410-b5e6-96231b3b80d8
2015-08-31 19:44:38 +00:00
David Majnemer
cc714e2142 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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239940 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-17 20:52:32 +00:00
Bjorn Steinbrink
0cb6d37dea Remove conflicting attributes before adding deduced readonly/readnone
Summary:
In case of functions that have a pointer argument and only pass it to
each other, the function attributes pass deduces that the pointer should
get the readnone attribute, but fails to remove a readonly attribute
that may already have been present.

Reviewers: nlewycky

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D9995

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238152 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-25 19:46:38 +00:00
David Blaikie
32b845d223 [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))

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235145 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-16 23:24:18 +00:00
David Blaikie
7c9c6ed761 [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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230794 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-27 21:17:42 +00:00
David Blaikie
198d8baafb [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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230786 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-27 19:29:02 +00:00
Paul Robinson
c3e82bf9f5 Normally an 'optnone' function goes through fast-isel, which does not
call DAGCombiner. But we ran into a case (on Windows) where the
calling convention causes argument lowering to bail out of fast-isel,
and we end up in CodeGenAndEmitDAG() which does run DAGCombiner.
So, we need to make DAGCombiner check for 'optnone' after all.

Commit includes the test that found this, plus another one that got
missed in the original optnone work.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221168 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-03 18:19:26 +00:00
Chandler Carruth
701073e58e [optnone] Make the optnone attribute effective at suppressing function
attribute and function argument attribute synthesizing and propagating.

As with the other uses of this attribute, the goal remains a best-effort
(no guarantees) attempt to not optimize the function or assume things
about the function when optimizing. This is particularly useful for
compiler testing, bisecting miscompiles, triaging things, etc. I was
hitting specific issues using optnone to isolate test code from a test
driver for my fuzz testing, and this is one step of fixing that.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215538 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-13 10:49:33 +00:00
Nick Lewycky
a35be5ab67 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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209870 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-30 02:31:27 +00:00
Reid Kleckner
59bec0e3c0 Update optimization passes to handle inalloca arguments
Summary:
I searched Transforms/ and Analysis/ for 'ByVal' and updated those call
sites to check for inalloca if appropriate.

I added tests for any change that would allow an optimization to fire on
inalloca.

Reviewers: nlewycky

Differential Revision: http://llvm-reviews.chandlerc.com/D2449

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200281 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-28 02:38:36 +00:00
Matt Arsenault
60ecc44266 Make nocapture analysis work with addrspacecast
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199246 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-14 19:11:52 +00:00
Daniel Dunbar
24ec2e5a72 [tests] Cleanup initialization of test suffixes.
- Instead of setting the suffixes in a bunch of places, just set one master
   list in the top-level config. We now only modify the suffix list in a few
   suites that have one particular unique suffix (.ml, .mc, .yaml, .td, .py).

 - Aside from removing the need for a bunch of lit.local.cfg files, this enables
   4 tests that were inadvertently being skipped (one in
   Transforms/BranchFolding, a .s file each in DebugInfo/AArch64 and
   CodeGen/PowerPC, and one in CodeGen/SI which is now failing and has been
   XFAILED).

 - This commit also fixes a bunch of config files to use config.root instead of
   older copy-pasted code.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188513 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-16 00:37:11 +00:00
Tim Northover
dcef6a7400 Fix FileCheck --check-prefix lines.
Various tests had sprung up over the years which had --check-prefix=ABC on the
RUN line, but "CHECK-ABC:" later on. This happened to work before, but was
strictly incorrect. FileCheck is getting stricter soon though.

Patch by Ron Ofir.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188173 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-12 12:43:26 +00:00
Stephen Lin
39f4e8d9cc 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


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186268 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-14 01:42:54 +00:00
Nick Lewycky
dc89737bcd 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185735 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-06 00:29:58 +00:00
Michael Gottesman
7cbdd90982 Change the gettimeofday test to only test on a posix platform.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185503 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-03 04:15:22 +00:00
Michael Gottesman
7cb0321ad8 Added support in FunctionAttrs for adding relevant function/argument attributes for the posix call gettimeofday.
This implies annotating it as nounwind and its arguments as nocapture. To be
conservative, we do not annotate the arguments with noalias since some platforms
do not have restrict on the declaration for gettimeofday.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185502 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-03 04:00:54 +00:00
Meador Inge
cf47ce616c Move library call prototype attribute inference to functionattrs
The simplify-libcalls pass implemented a doInitialization hook to infer
function prototype attributes for well-known functions.  Given that the
simplify-libcalls pass is going away *and* that the functionattrs pass
is already in place to deduce function attributes, I am moving this logic
to the functionattrs pass.  This approach was discussed during patch
review:
http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20121126/157465.html.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177619 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-21 00:55:59 +00:00
Bill Wendling
7ab6c76ad1 Modify the LLVM assembly output so that it uses references to represent function attributes.
This makes the LLVM assembly look better. E.g.:

     define void @foo() #0 { ret void }
     attributes #0 = { nounwind noinline ssp }


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175605 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-20 07:21:42 +00:00
Nadav Rotem
03544ec2a4 Fix a bug in mayHaveSideEffects. Functions that do not return are now considered as instructions with side effects.
rdar://13227456



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175553 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-19 20:02:09 +00:00
Bill Wendling
595ef3e314 FileCheck-ize the tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174865 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-11 08:34:57 +00:00
Bill Wendling
606c8e36df Convert getAttributes() to return an AttributeSetNode.
The AttributeSetNode contains all of the attributes. This removes one (hopefully
last) use of the Attribute class as a container of multiple attributes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173761 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-29 03:20:31 +00:00
Chandler Carruth
4177e6fff5 Convert all tests using TCL-style quoting to use shell-style quoting.
This was done through the aid of a terrible Perl creation. I will not
paste any of the horrors here. Suffice to say, it require multiple
staged rounds of replacements, state carried between, and a few
nested-construct-parsing hacks that I'm not proud of. It happens, by
luck, to be able to deal with all the TCL-quoting patterns in evidence
in the LLVM test suite.

If anyone is maintaining large out-of-tree test trees, feel free to poke
me and I'll send you the steps I used to convert things, as well as
answer any painful questions etc. IRC works best for this type of thing
I find.

Once converted, switch the LLVM lit config to use ShTests the same as
Clang. In addition to being able to delete large amounts of Python code
from 'lit', this will also simplify the entire test suite and some of
lit's architecture.

Finally, the test suite runs 33% faster on Linux now. ;]
For my 16-hardware-thread (2x 4-core xeon e5520): 36s -> 24s

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159525 91177308-0d34-0410-b5e6-96231b3b80d8
2012-07-02 12:47:22 +00:00
Eli Bendersky
0f0c411079 Replace all instances of dg.exp file with lit.local.cfg, since all tests are run with LIT now and now Dejagnu. dg.exp is no longer needed.
Patch reviewed by Daniel Dunbar. It will be followed by additional cleanup patches.




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150664 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-16 06:28:33 +00:00
Nick Lewycky
b48a18903a 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147327 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-28 23:24:21 +00:00
Nick Lewycky
d4659addf8 Move this test from date-name to feature-name, and port it to FileCheck.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147223 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-23 18:41:31 +00:00
Chris Lattner
d2bf432b2b Upgrade syntax of tests using volatile instructions to use 'load volatile' instead of 'volatile load', which is archaic.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145171 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-27 06:54:59 +00:00
Bill Wendling
aeaa9a8b25 Update some tests to the new EH scheme.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@138925 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-01 00:58:03 +00:00
Eli Friedman
34fd67c7bc Fix test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137703 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-16 01:42:56 +00:00
Eli Friedman
2199dfb0e6 Revert a bit of r137667; the logic in question can safely handle atomic load/store.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137702 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-16 01:28:22 +00:00
Chris Lattner
b85e4eba85 rip out a ton of intrinsic modernization logic from AutoUpgrade.cpp, which is
for pre-2.9 bitcode files.  We keep x86 unaligned loads, movnt, crc32, and the
target indep prefetch change.

As usual, updating the testsuite is a PITA.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133337 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-18 06:05:24 +00:00