Commit Graph

4470 Commits

Author SHA1 Message Date
Bob Wilson
a0be09f511 Add LLVMContext::emitWarning methods and use them. <rdar://problem/12867368>
When the backend is used from clang, it should produce proper diagnostics
instead of just printing messages to errs(). Other clients may also want to
register their own error handlers with the LLVMContext, and the same handler
should work for warnings in the same way as the existing emitError methods.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171041 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-24 18:15:21 +00:00
Nadav Rotem
99b7a99376 Update the docs of the cost model.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171016 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-24 05:51:12 +00:00
Craig Topper
c4265e1d68 Remove trailing whitespace.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170991 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-22 19:15:35 +00:00
James Molloy
67ae135759 Add a new attribute, 'noduplicate'. If a function contains a noduplicate call, the call cannot be duplicated - Jump threading, loop unrolling, loop unswitching, and loop rotation are inhibited if they would duplicate the call.
Similarly inlining of the function is inhibited, if that would duplicate the call (in particular inlining is still allowed when there is only one callsite and the function has internal linkage).



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170704 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-20 16:04:27 +00:00
Nadav Rotem
521396ab37 Fix a bug that was found by building clang with -fsanitize.
I introduced it in r166785. PR14291.

If TD is unavailable use getScalarSizeInBits, but don't optimize
pointers or vectors of pointers.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170586 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-19 20:47:04 +00:00
Bill Wendling
034b94b170 Rename the 'Attributes' class to 'Attribute'. It's going to represent a single attribute in the future.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170502 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-19 07:18:57 +00:00
Nadav Rotem
fd360c3e24 Fix a crash in ValueTracking on vectors of pointers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170240 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-14 20:43:49 +00:00
Rafael Espindola
dbaa2376f7 Rename isPowerOfTwo to isKnownToBeAPowerOfTwo.
In a previous thread it was pointed out that isPowerOfTwo is not a very precise
name since it can return false for powers of two if it is unable to show that
they are powers of two.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170093 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-13 03:37:24 +00:00
Rafael Espindola
b09c146b11 The TargetData is not used for the isPowerOfTwo determination. It has never
been used in the first place.  It simply was passed to the function and to the
recursive invocations.  Simply drop the parameter and update the callers for the
new signature.

Patch by Saleem Abdulrasool!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169988 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-12 16:52:40 +00:00
Michael Ilseman
d0a0d221da Have SimplifyBinOp call the new FAdd/FSub/FMul helpers, with fast-math flags off
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169943 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-12 00:29:16 +00:00
Michael Ilseman
09ee250e72 Added a slew of SimplifyInstruction floating-point optimizations, many of which take advantage of fast-math flags. Test cases included.
fsub X, +0 ==> X
  fsub X, -0 ==> X, when we know X is not -0
  fsub +/-0.0, (fsub -0.0, X) ==> X
  fsub nsz +/-0.0, (fsub +/-0.0, X) ==> X
  fsub nnan ninf X, X ==> 0.0
  fadd nsz X, 0 ==> X
  fadd [nnan ninf] X, (fsub [nnan ninf] 0, X) ==> 0
    where nnan and ninf have to occur at least once somewhere in this expression
  fmul X, 1.0 ==> X



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169940 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-12 00:27:46 +00:00
Chandler Carruth
7550f96b2f Holding my nose and moving the accumulation routine to GEPOperator
instead of the instruction. I've left a forwarding wrapper for the
instruction so users with the instruction don't need to create
a GEPOperator themselves.

This lets us remove the copy of this code in instsimplify.

I've looked at most of the other copies of similar code, and this is the
only one I've found that is actually exactly the same. The one in
InlineCost is very close, but it requires re-mapping non-constant
indices through the cost analysis value simplification map. I could add
direct support for this to the generic routine, but it seems overly
specific.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169853 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-11 11:05:15 +00:00
Chandler Carruth
4ced4ee94b Hoist the GEP constant address offset computation to a common home on
the GEP instruction class.

This is part of the continued refactoring and cleaning of the
infrastructure used by SROA. This particular operation is also done in
a few other places which I'll try to refactor to share this
implementation.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169852 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-11 10:29:10 +00:00
Arnold Schwaighofer
2b475922e6 Optimistically analyse Phi cycles
Analyse Phis under the starting assumption that they are NoAlias. Recursively
look at their inputs.
If they MayAlias/MustAlias there must be an input that makes them so.

Addresses bug 14351.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169788 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-10 23:02:41 +00:00
Chandler Carruth
ed90ed077a Add a new visitor for walking the uses of a pointer value.
This visitor provides infrastructure for recursively traversing the
use-graph of a pointer-producing instruction like an alloca or a malloc.
It maintains a worklist of uses to visit, so it can handle very deep
recursions. It automatically looks through instructions which simply
translate one pointer to another (bitcasts and GEPs). It tracks the
offset relative to the original pointer as long as that offset remains
constant and exposes it during the visit as an APInt offset. Finally, it
performs conservative escape analysis.

However, currently it has some limitations that should be addressed
going forward:
1) It doesn't handle vectors of pointers.
2) It doesn't provide a cheaper visitor when the constant offset
   tracking isn't needed.
3) It doesn't support non-instruction pointer values.

The current functionality is exactly what is required to implement the
SROA pointer-use visitors in terms of this one, rather than in terms of
their own ad-hoc base visitor, which was always very poorly specified.
SROA has been converted to use this, and the code there deleted which
this utility now provides.

Technically speaking, using this new visitor allows SROA to handle a few
more cases than it previously did. It is now more aggressive in ignoring
chains of instructions which look like they would defeat SROA, but in
fact do not because they never result in a read or write of memory.
While this is "neat", it shouldn't be interesting for real programs as
any such chains should have been removed by others passes long before we
get to SROA. As a consequence, I've not added any tests for these
features -- it shouldn't be part of SROA's contract to perform such
heroics.

The goal is to extend the functionality of this visitor going forward,
and re-use it from passes like ASan that can benefit from doing
a detailed walk of the uses of a pointer.

Thanks to Ben Kramer for the code review rounds and lots of help
reviewing and debugging this patch.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169728 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-10 08:28:39 +00:00
Michael Ilseman
1638b83909 Reorganize FastMathFlags to be a wrapper around unsigned, and streamline some interfaces.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169712 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-09 21:12:04 +00:00
Chandler Carruth
70d3bebc8b Add support to ValueTracking for determining that a pointer is non-null
by virtue of inbounds GEPs that preclude a null pointer.

This is a very common pattern in the code generated by std::vector and
other standard library routines which use allocators that test for null
pervasively. This is one step closer to teaching Clang+LLVM to be able
to produce an empty function for:

  void f() {
    std::vector<int> v;
    v.push_back(1);
    v.push_back(2);
    v.push_back(3);
    v.push_back(4);
  }

Which is related to getting them to completely fold SmallVector
push_back sequences into constants when inlining and other optimizations
make that a possibility.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169573 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-07 02:08:58 +00:00
Michael Ilseman
85893f48a6 Have CannotBeNegativeZero() be aware of the nsz fast-math flag
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169452 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-06 00:07:09 +00:00
Nadav Rotem
e70b2680a8 constify the cost API
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169172 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-03 22:47:12 +00:00
Chandler Carruth
d04a8d4b33 Use the new script to sort the includes of every file under lib.
Sooooo many of these had incorrect or strange main module includes.
I have manually inspected all of these, and fixed the main module
include to be the nearest plausible thing I could find. If you own or
care about any of these source files, I encourage you to take some time
and check that these edits were sensible. I can't have broken anything
(I strictly added headers, and reordered them, never removed), but they
may not be the headers you'd really like to identify as containing the
API being implemented.

Many forward declarations and missing includes were added to a header
files to allow them to parse cleanly when included first. The main
module rule does in fact have its merits. =]

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169131 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-03 16:50:05 +00:00
Chandler Carruth
84bcf93e0f Move the InstVisitor utility into VMCore where it belongs. It heavily
depends on the IR infrastructure, there is no sense in it being off in
Support land.

This is in preparation to start working to expand InstVisitor into more
special-purpose visitors that are still generic and can be re-used
across different passes. The expansion will go into the Analylis tree
though as nothing in VMCore needs it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168972 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-30 03:08:41 +00:00
Preston Briggs
a4eff77e37 Modified dump() to provide a little
more information for dependences between
instructions that don't share a common loop.

Updated the test results appropriately.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168965 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-30 00:44:47 +00:00
Benjamin Kramer
7d4253af16 Follow up to 168711: It's safe to base this analysis on the found compare, just return the value for the right predicate.
Thanks to Andy for catching this.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168921 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-29 19:07:57 +00:00
Andrew Trick
ffc9ee4bbf Improve isImpliedCond comment a bit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168914 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-29 18:35:13 +00:00
Preston Briggs
a18d377e73 Cleaned up a couple of comments.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168854 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-29 04:30:52 +00:00
Preston Briggs
3c1cc3888b Modified depends() to recognize that when all levels are "=" and
there's no possible loo-independent dependence, then there's no
dependence.

Updated all test result appropriately.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168719 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-27 19:12:26 +00:00
Benjamin Kramer
b2a818f83b SCEV: Even if the latch terminator is foldable we can't deduce the result of an unrelated condition with it.
Fixes PR14432.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168711 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-27 18:16:32 +00:00
Preston Briggs
6ee74f52e9 Modify depends(Src, Dst, PossiblyLoopIndependent).
If the Src and Dst are the same instruction,
no loop-independent dependence is possible,
so we force the PossiblyLoopIndependent flag to false.

The test case results are updated appropriately.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168678 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-27 06:41:46 +00:00
Michael Ilseman
eb61c920f1 Fast-math optimization: fold multiply by zero
Added in first optimization using fast-math flags to serve as an example for following optimizations. SimplifyInstruction will now try to optimize an fmul observing its FastMathFlags to see if it can fold multiply by zero when 'nnan' and 'nsz' flags are set.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168648 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-27 00:46:26 +00:00
Preston Briggs
72a2c0622a Corrects a problem where we reply exclusively of GEPs to drive
analysis.  Better is to look for cases with useful GEPs and use them
when possible.  When a pair of useful GEPs is not available, use the
raw SCEVs directly. This approach supports better analysis of pointer
dereferencing.

In parallel, all the test cases are updated appropriately.
Cases where we have a store to *B++ can now be analyzed!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168474 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-21 23:50:04 +00:00
Sebastian Pop
7372a7d5f8 removes a few "const" qualifiers
so that I can (someday) call SE->getSCEV without complaint.
No semantic change intended.

Patch from Preston Briggs <preston.briggs@gmail.com>.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168391 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-20 22:28:04 +00:00
Bob Wilson
28f872f8a1 Clean up handling of always-inline functions in the inliner.
This patch moves the isInlineViable function from the InlineAlways pass into
the InlineCostAnalyzer and then changes the InlineCost computation to use that
simple check for always-inline functions. All the special-case checks for
AlwaysInline in the CallAnalyzer can then go away.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168300 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-19 07:04:35 +00:00
Bob Wilson
593423f746 Some comment fixes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168299 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-19 07:04:30 +00:00
Hal Finkel
c37f502d48 Phi speculation improvement for BasicAA
This is a partial solution to PR14351. It removes some of the special
significance of the first incoming phi value in the phi aliasing checking logic
in BasicAA. In the context of a loop, the old logic assumes that the first
incoming value is the interesting one (meaning that it is the one that comes
from outside the loop), but this is often not the case.  With this change, we
now test first the incoming value that comes from a block other than the parent
of the phi being tested.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168245 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-17 02:33:15 +00:00
Duncan Sands
4f0dfbb454 Make this easier to understand, as suggested by Chandler.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168196 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-16 20:53:08 +00:00
Duncan Sands
aceb03eb58 InstructionSimplify should be able to simplify A+B==B+A to 'true'
but wasn't due to the same logic bug that caused PR14361.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168186 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-16 19:41:26 +00:00
Owen Anderson
40b6fdb81e Add doInitialization and doFinalization methods to ModulePass's, to allow them to be re-initialized and reused on multiple Module's.
Patch by Pedro Artigas.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168008 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-15 00:14:15 +00:00
Benjamin Kramer
563e8fce2e DependenceAnalysis: Print all dependency pairs when dumping. Update all testcases.
Part of a patch by Preston Briggs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167827 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-13 12:12:02 +00:00
NAKAMURA Takumi
562b1d883f llvm/ConstantFolding.cpp: Make ReadDataFromGlobal() and FoldReinterpretLoadFromConstPtr() Big-endian-aware.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167595 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-08 20:34:25 +00:00
Richard Osborne
544533301e Don't infer whether a value is captured in the current function from the
'nocapture' attribute.

The nocapture attribute only specifies that no copies are made that
outlive the function. This isn't the same as there being no copies at all.
This fixes PR14045.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167381 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-05 10:48:24 +00:00
NAKAMURA Takumi
db2b285225 ConstantFolding.cpp: Whitespace.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167377 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-05 00:11:11 +00:00
Duncan Sands
a1beca6845 Apply the patch from PR14160. I failed to construct a testcase for this, but
I'm applying it anyway since it seems to be obviously correct.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167370 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-04 09:02:45 +00:00
Nadav Rotem
f149567160 CostModel: add support for Vector Insert and Extract.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167329 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-02 22:31:56 +00:00
Nadav Rotem
6bed58ef24 Add a cost model analysis that allows us to estimate the cost of IR-level instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167324 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-02 21:48:17 +00:00
Chandler Carruth
426c2bf5cd Revert the majority of the next patch in the address space series:
r165941: Resubmit the changes to llvm core to update the functions to
         support different pointer sizes on a per address space basis.

Despite this commit log, this change primarily changed stuff outside of
VMCore, and those changes do not carry any tests for correctness (or
even plausibility), and we have consistently found questionable or flat
out incorrect cases in these changes. Most of them are probably correct,
but we need to devise a system that makes it more clear when we have
handled the address space concerns correctly, and ideally each pass that
gets updated would receive an accompanying test case that exercises that
pass specificaly w.r.t. alternate address spaces.

However, from this commit, I have retained the new C API entry points.
Those were an orthogonal change that probably should have been split
apart, but they seem entirely good.

In several places the changes were very obvious cleanups with no actual
multiple address space code added; these I have not reverted when
I spotted them.

In a few other places there were merge conflicts due to a cleaner
solution being implemented later, often not using address spaces at all.
In those cases, I've preserved the new code which isn't address space
dependent.

This is part of my ongoing effort to clean out the partial address space
code which carries high risk and low test coverage, and not likely to be
finished before the 3.2 release looms closer. Duncan and I would both
like to see the above issues addressed before we return to these
changes.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167222 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-01 09:14:31 +00:00
Chandler Carruth
ece6c6bb63 Revert the series of commits starting with r166578 which introduced the
getIntPtrType support for multiple address spaces via a pointer type,
and also introduced a crasher bug in the constant folder reported in
PR14233.

These commits also contained several problems that should really be
addressed before they are re-committed. I have avoided reverting various
cleanups to the DataLayout APIs that are reasonable to have moving
forward in order to reduce the amount of churn, and minimize the number
of commits that were reverted. I've also manually updated merge
conflicts and manually arranged for the getIntPtrType function to stay
in DataLayout and to be defined in a plausible way after this revert.

Thanks to Duncan for working through this exact strategy with me, and
Nick Lewycky for tracking down the really annoying crasher this
triggered. (Test case to follow in its own commit.)

After discussing with Duncan extensively, and based on a note from
Micah, I'm going to continue to back out some more of the more
problematic patches in this series in order to ensure we go into the
LLVM 3.2 branch with a reasonable story here. I'll send a note to
llvmdev explaining what's going on and why.

Summary of reverted revisions:

r166634: Fix a compiler warning with an unused variable.
r166607: Add some cleanup to the DataLayout changes requested by
         Chandler.
r166596: Revert "Back out r166591, not sure why this made it through
         since I cancelled the command. Bleh, sorry about this!
r166591: Delete a directory that wasn't supposed to be checked in yet.
r166578: Add in support for getIntPtrType to get the pointer type based
         on the address space.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167221 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-01 08:07:29 +00:00
Benjamin Kramer
e803d05bd8 Fix a couple of comment typos.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167113 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-31 11:25:32 +00:00
Benjamin Kramer
061938b90b DependenceAnalysis: Don't crash if there is no constant operand.
This makes the code match the comments. Resolves a crash in loop idiom (PR14219).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167110 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-31 09:20:38 +00:00
Bob Wilson
6a09098cca Remove code to saturate profile counts.
We may need to change the way profile counter values are stored, but
saturation is the wrong thing to do.  Just remove it for now.

Patch by Alastair Murray!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166938 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-29 17:27:39 +00:00
Benjamin Kramer
974d98d730 SCEV validator: Ignore CouldNotCompute/undef on both sides. This is mostly noise and blocks finding more severe bugs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166873 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-27 11:36:07 +00:00