Commit Graph

39 Commits

Author SHA1 Message Date
Dan Gohman
43d836343e Document another instsimplify assumption.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174100 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-31 22:13:00 +00:00
Dan Gohman
c4e441804e Add a comment mentioning that InstructionSimplify routines do,
in fact, resolve undef uses.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173721 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-28 21:45:32 +00:00
Chandler Carruth
0b8c9a80f2 Move all of the header files which are involved in modelling the LLVM IR
into their new header subdirectory: include/llvm/IR. This matches the
directory structure of lib, and begins to correct a long standing point
of file layout clutter in LLVM.

There are still more header files to move here, but I wanted to handle
them in separate commits to make tracking what files make sense at each
layer easier.

The only really questionable files here are the target intrinsic
tablegen files. But that's a battle I'd rather not fight today.

I've updated both CMake and Makefile build systems (I think, and my
tests think, but I may have missed something).

I've also re-sorted the includes throughout the project. I'll be
committing updates to Clang, DragonEgg, and Polly momentarily.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171366 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-02 11:36:10 +00:00
Chandler Carruth
e949aa1c91 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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171194 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-28 14:23:29 +00:00
Chandler Carruth
c98bd9f1a7 Add entry points to instsimplify for simplifying calls. The entry points
are nice and decomposed so that we can simplify synthesized calls as
easily as actually call instructions. The internal utility still has the
same behavior, it just now operates on a more generic interface so that
I can extend the set of call simplifications that instsimplify knows
about.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171189 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-28 11:30:55 +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
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
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
Michael Ilseman
407a6169b7 Remove trailing whitespace
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168103 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-15 22:34:00 +00:00
Micah Villmow
3574eca1b0 Move TargetData to DataLayout.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165402 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-08 16:38:25 +00:00
Chandler Carruth
6b980541df Refactor the interface to recursively simplifying instructions to be tad
bit simpler by handling a common case explicitly.

Also, refactor the implementation to use a worklist based walk of the
recursive users, rather than trying to use value handles to detect and
recover from RAUWs during the recursive descent. This fixes a very
subtle bug in the previous implementation where degenerate control flow
structures could cause mutually recursive instructions (PHI nodes) to
collapse in just such a way that From became equal to To after some
amount of recursion. At that point, we hit the inf-loop that the assert
at the top attempted to guard against. This problem is defined away when
not using value handles in this manner. There are lots of comments
claiming that the WeakVH will protect against just this sort of error,
but they're not accurate about the actual implementation of WeakVHs,
which do still track RAUWs.

I don't have any test case for the bug this fixes because it requires
running the recursive simplification on unreachable phi nodes. I've no
way to either run this or easily write an input that triggers it. It was
found when using instruction simplification inside the inliner when
running over the nightly test-suite.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153393 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-24 21:11:24 +00:00
Duncan Sands
bd0fe56425 Generalize the "trunc(ptrtoint(x)) - trunc(ptrtoint(y)) ->
trunc(ptrtoint(x-y))" optimization introduced by Chandler.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152626 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-13 14:07:05 +00:00
Duncan Sands
0aa85eb231 Uniformize the InstructionSimplify interface by ensuring that all routines
take a TargetLibraryInfo parameter.  Internally, rather than passing TD, TLI
and DT parameters around all over the place, introduce a struct for holding
them.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152623 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-13 11:42:19 +00:00
Chad Rosier
618c1dbd29 Propagate TargetLibraryInfo throughout ConstantFolding.cpp and
InstructionSimplify.cpp.  Other fixups as needed.
Part of rdar://10500969

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145559 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-01 03:08:23 +00:00
Duncan Sands
dabc280672 Add some simple insertvalue simplifications, for the purpose of cleaning
up do-nothing exception handling code produced by dragonegg.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139113 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-05 06:52:48 +00:00
Jay Foad
b9b54ebfed Convert SimplifyGEPInst to use ArrayRef.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135482 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-19 15:07:52 +00:00
Duncan Sands
194cfb08ff Forgot to commit the changes to this file.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130695 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-02 16:34:19 +00:00
Chris Lattner
81a0dc9115 Teach instsimplify some tricks about exact/nuw/nsw shifts.
improve interfaces to instsimplify to take this info.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125196 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-09 17:15:04 +00:00
Frits van Bommel
1fca2c32cc Move InstCombine's knowledge of fdiv to SimplifyInstruction().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124534 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-29 15:26:31 +00:00
Duncan Sands
593faa53fa My auto-simplifier noticed that ((X/Y)*Y)/Y occurs several times in SPEC
benchmarks, and that it can be simplified to X/Y.  (In general you can only
simplify (Z*Y)/Y to Z if the multiplication did not overflow; if Z has the
form "X/Y" then this is the case).  This patch implements that transform and
moves some Div logic out of instcombine and into InstructionSimplify.
Unfortunately instcombine gets in the way somewhat, since it likes to change
(X/Y)*Y into X-(X rem Y), so I had to teach instcombine about this too.
Finally, thanks to the NSW/NUW flags, sometimes we know directly that "Z*Y"
does not overflow, because the flag says so, so I added that logic too.  This
eliminates a bunch of divisions and subtractions in 447.dealII, and has good
effects on some other benchmarks too.  It seems to have quite an effect on
tramp3d-v4 but it's hard to say if it's good or bad because inlining decisions
changed, resulting in massive changes all over.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124487 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-28 16:51:11 +00:00
Duncan Sands
c43cee3fbb Move some shift transforms out of instcombine and into InstructionSimplify.
While there, I noticed that the transform "undef >>a X -> undef" was wrong.
For example if X is 2 then the top two bits must be equal, so the result can
not be anything.  I fixed this in the constant folder as well.  Also, I made
the transform for "X << undef" stronger: it now folds to undef always, even
though X might be zero.  This is in accordance with the LangRef, but I must
admit that it is fairly aggressive.  Also, I added "i32 X << 32 -> undef"
following the LangRef and the constant folder, likewise fairly aggressive.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123417 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-14 00:37:45 +00:00
Duncan Sands
19f14dcf6a Clarify that InstructionSimplify only returns values that dominate the
original instruction.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122601 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-28 18:01:19 +00:00
Duncan Sands
82fdab3358 Pull a few more simplifications out of instcombine (there are still
plenty left though!), in particular for multiplication.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122330 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-21 14:00:22 +00:00
Duncan Sands
fea3b218d6 Move Sub simplifications and additional Add simplifications out of
instcombine and into InstructionSimplify.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121861 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-15 14:07:39 +00:00
Duncan Sands
4cd2ad15b4 Expand a little on the description of what InstructionSimplify does.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120016 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-23 10:50:08 +00:00
Duncan Sands
2b749870d0 Move some those Xor simplifications which don't require creating new
instructions out of InstCombine and into InstructionSimplify.  While
there, introduce an m_AllOnes pattern to simplify matching with integers
and vectors with all bits equal to one.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119536 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-17 18:52:15 +00:00
Duncan Sands
d261dc650a Previously SimplifyInstruction could report that an instruction
simplified to itself (this can only happen in unreachable blocks).
Change it to return null instead.  Hopefully this will fix some
buildbot failures.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119490 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-17 08:35:29 +00:00
Duncan Sands
1845009290 In which I discover the existence of loops. Threading an operation
over a phi node by applying it to each operand may be wrong if the
operation and the phi node are mutually interdependent (the testcase
has a simple example of this).  So only do this transform if it would
be correct to perform the operation in each predecessor of the block
containing the phi, i.e. if the other operands all dominate the phi.
This should fix the FFMPEG snow.c regression reported by İsmail Dönmez.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119347 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-16 12:16:38 +00:00
Duncan Sands
eff0581583 If dom tree information is available, make it possible to pass
it to get better phi node simplification.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119055 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-14 18:36:10 +00:00
Duncan Sands
12a86f5b31 Strip trailing whitespace.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119038 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-14 11:23:23 +00:00
Owen Anderson
4e282decf3 Revert r114097, adding back in the assertion against replacing an Instruction by itself. Now that CorrelatedValuePropagation is
more careful not to call SimplifyInstructionsInBlock() on an unreachable block, the issue has been fixed at a higher level.  Add
a big warning to SimplifyInstructionsInBlock() to hopefully prevent this in the future.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114117 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-16 20:51:41 +00:00
Chris Lattner
047542669a move some select simplifications out out instcombine into
inst simplify.  No functionality change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101873 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-20 05:32:14 +00:00
Chris Lattner
8aee8efc0c factor some logic out of instcombine into a new SimplifyAddInst method.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90011 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-27 17:42:22 +00:00
Chris Lattner
c514c1f521 factor some instcombine simplifications for getelementptr out to a new
SimplifyGEPInst method in InstructionSimplify.h.  No functionality change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89980 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-27 00:29:05 +00:00
Chris Lattner
40d8c28b27 move some generally useful functions out of jump threading
into libanalysis and transformutils.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86735 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-10 22:26:15 +00:00
Chris Lattner
e34537856a add a new SimplifyInstruction API, which is like ConstantFoldInstruction,
except that the result may not be a constant.  Switch jump threading to 
use it so that it gets things like (X & 0) -> 0, which occur when phi preds
are deleted and the remaining phi pred was a zero.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86637 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-10 01:08:51 +00:00
Chris Lattner
d06094f068 factor simplification logic for AND and OR out to InstSimplify from instcombine.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86635 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-10 00:55:12 +00:00
Chris Lattner
9dbb42944c rename SimplifyCompare -> SimplifyCmpInst and split it into
Simplify[IF]Cmp pieces.  Add some predicates to CmpInst to 
determine whether a predicate is fp or int.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86624 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-09 23:28:39 +00:00
Chris Lattner
9f3c25aeb3 stub out a new libanalysis "instruction simplify" interface that
takes decimated instructions and applies identities to them.  This
is pretty minimal at this point, but I plan to pull some instcombine
logic out into these and similar routines.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86613 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-09 22:57:59 +00:00