Commit Graph

22 Commits

Author SHA1 Message Date
Duncan Sands
92826def59 Add simplification of floating point comparisons with the result
of a select instruction, the same as already exists for integer
comparisons.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118379 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-07 16:46:25 +00:00
Duncan Sands
1ac7c9979a Fix a README item: when doing a comparison with the result
of a select instruction, see if doing the compare with the
true and false values of the select gives the same result.
If so, that can be used as the value of the comparison.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118378 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-07 16:12:23 +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
Owen Anderson
4b91c3ac96 Fix PR8161, in which an unreachable loop causes recursive instruction simplification to try
to replace an instruction with itself.  Add a predicate to the simplifier to prevent this case.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114097 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-16 17:42:36 +00:00
Benjamin Kramer
6844c8ea5a Teach InstructionSimplify to fold (A & B) & A -> A & B and (A | B) | A -> A | B.
Reassociate does this but it doesn't catch all cases (e.g. if the operands are i1).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@113651 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-10 22:39:55 +00:00
Chris Lattner
d2bfe54b0a Fix PR7647, handling the case when 'To' ends up being
mutated by recursive simplification.  This also enhances
ReplaceAndSimplifyAllUses to actually do a real RAUW
at the end of it, which updates any value handles
pointing to "From" to start pointing to "To".  This
seems useful for debug info and random other VH users.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108415 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-15 06:36:08 +00:00
Eli Friedman
e2f93131fb Revert r108401; it breaks bootstrap :(
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108407 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-15 05:09:31 +00:00
Eli Friedman
3ed60a2a22 Add AssertingVH which makes PR7647 break consistently.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108401 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-15 04:46:14 +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
c8e14b3d37 fix incorrect folding of icmp with undef, PR6481.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97659 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-03 19:46:03 +00:00
Dan Gohman
6b617a7213 Constant-fold certain comparisons with infinity and negative infinity.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96777 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-22 04:06:03 +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
70ce6d0819 I misread the parens, not so redundant after all.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86648 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-10 02:04:54 +00:00
Chris Lattner
9f3ce36d7e remove some redundant parens.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86645 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-10 01:56:04 +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
210c5d4880 pull a bunch of logic out of instcombine into instsimplify for compare
simplification, this handles the foldable fcmp x,x cases among many others.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86627 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-09 23:55:12 +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
8f73deaa87 fix ConstantFoldCompareInstOperands to take the LHS/RHS as
individual operands instead of taking a temporary array


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86619 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-09 23:06:58 +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