For example, on 32-bit architecture, don't promote all uses of the IV
to 64-bits just because one use is a 64-bit cast.
Alternate implementation of the patch by Arnaud de Grandmaison.
llvm-svn: 127884
SCEV may generate expressions composed of multiple pointers, which can
lead to invalid GEP expansion. Until we can teach SCEV to follow strict
pointer rules, make sure no bad GEPs creep into IR.
Fixes rdar://problem/9038671.
llvm-svn: 127839
memory builtins as equivalent to malloc/free.
This is different from any attribute we have. For example, you can delete the
allocators when their result is unused, but you can't collapse two calls to the
same function, even if no global/memory state has changed in between. The
noalias return states that the result does not alias any other pointer, but
instcombine optimizes malloc() as though the result is non-null for the purpose
of eliminating unused pointers.
llvm-svn: 127673
properties.
Added the self-wrap flag for SCEV::AddRecExpr.
A slew of temporary FIXMEs indicate the intention of the no-self-wrap flag
without changing behavior in this revision.
llvm-svn: 127590
It generates output that lools like
8 times line number info lost by Scalar Replacement of Aggregates (SSAUp)
1 times line number info lost by Simplify well-known library calls
12 times variable info lost by Jump Threading
llvm-svn: 127381
When ExactBECount is a constant, use it for MaxBECount.
When MaxBECount cannot be computed, replace it with ExactBECount.
Fixes PR9424.
llvm-svn: 127342
gave up when I realized I couldn't come up with a good name for what the
refactored function would be, to describe what it does.
This is PR9343 test12, which is test3 with arguments reordered. Whoops!
llvm-svn: 127318
possible. This goes into instcombine and instsimplify because instsimplify
doesn't need to check hasOneUse since it returns (almost exclusively) constants.
This fixes PR9343 #4#5 and #8!
llvm-svn: 127064
"icmp pred %X, CI" and a number of examples where "%X = binop %Y, CI2".
Some of these cases (div and rem) used to make it through opt -O2, but the
others are probably now making code elsewhere redundant (probably instcombine).
llvm-svn: 126988
Use 8 bits from line number field to keep track of argument ordering while encoding debug info for an argument. That leaves 24 bit for line no, DebugLoc also allocates 24 bit for line numbers. If a function has more than 255 arguments then rest of the arguments will be ordered by llvm.dbg.* intrinsics' ordering in IR.
llvm-svn: 126793
plus some variations of this. According to my auto-simplifier this occurs a lot
but usually in combination with max/min idioms. Because max/min aren't handled
yet this unfortunately doesn't have much effect in the testsuite.
llvm-svn: 125462
unsigned overflow (e.g. "gep P, -1"), and while they can have
signed wrap in theoretical situations, modelling an AddRec as
not having signed wrap is going enough for any case we can
think of today. In the future if this isn't enough, we can
revisit this. Modeling them as having NUW isn't causing any
known problems either FWIW.
llvm-svn: 125410
versions of creation functions. Eventually, the "insertion point" versions
of these should just be removed, we do have IRBuilder afterall.
Do a massive rewrite of much of pattern match. It is now shorter and less
redundant and has several other widgets I will be using in other patches.
Among other changes, m_Div is renamed to m_IDiv (since it only matches
integer divides) and m_Shift is gone (it used to match all binops!!) and
we now have m_LogicalShift for the one client to use.
Enhance IRBuilder to have "isExact" arguments to things like CreateUDiv
and reduce redundancy within IRbuilder by having these methods chain to
each other more instead of duplicating code.
llvm-svn: 125194
a) Making it a per call site bonus for functions that we can move from
indirect to direct calls.
b) Reduces the bonus from 500 to 100 per call site.
c) Subtracts the size of the possible newly inlineable call from the
bonus to only add a bonus if we can inline a small function to devirtualize
it.
Also changes the bonus from a positive that's subtracted to a negative
that's added.
Fixes the remainder of rdar://8546196 by reducing the object file size
after inlining by 84%.
llvm-svn: 124916
auto-simplifier). This has a big impact on Ada code, but not much else.
Unfortunately the impact is mostly negative! This is due to PR9004 (aka
SCCP failing to resolve conditional branch conditions in the destination
blocks of the branch), in which simple correlated expressions are not
resolved but complicated ones are, so simplifying has a bad effect!
llvm-svn: 124788
overflow (nsw flag), which was disabled because it breaks 254.gap. I have
informed the GAP authors of the mistake in their code, and arranged for the
testsuite to use -fwrapv when compiling this benchmark.
llvm-svn: 124746
to do this and more, but would only do it if X/Y had only one use. Spotted as the
most common missed simplification in SPEC by my auto-simplifier, now that it knows
about nuw/nsw/exact flags. This removes a bunch of multiplications from 447.dealII
and 483.xalancbmk. It also removes a lot from tramp3d-v4, which results in much
more inlining.
llvm-svn: 124560
Modified patch by Adam Preuss.
This builds on the existing framework for block tracing, edge profiling and optimal edge profiling.
See -help-hidden for new flags.
For documentation, see the technical report "Implementation of Path Profiling..." in llvm.org/pubs.
llvm-svn: 124515
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.
llvm-svn: 124487
doesn't return immediately after then the insert position in UniqueSCEVs will
be out of date. No test because this is a memory corruption issue. Fixes PR9051!
llvm-svn: 124282
a few loops accordingly. Should be no functional change.
This is a step for more accurate cost/benefit analysis of devirt/inlining
bonuses.
llvm-svn: 124275
optimized code are:
(non-negative number)+(power-of-two) != 0 -> true
and
(x | 1) != 0 -> true
Instcombine knows about the second one of course, but only does it if X|1
has only one use. These fire thousands of times in the testsuite.
llvm-svn: 124183
with BasicAA's DecomposeGEPExpression, which recently began
using a TargetData. This fixes PR8968, though the testcase
is awkward to reduce.
Also, update several off GetUnderlyingObject's users
which happen to have a TargetData handy to pass it in.
llvm-svn: 124134
clang's -Wuninitialized-experimental warning.
While these don't look like real bugs, clang's
-Wuninitialized-experimental analysis is stricter
than GCC's, and these fixes have the benefit
of being general nice cleanups.
llvm-svn: 124073
auto-simplier the transform most missed by early-cse is (zext X) != 0 -> X != 0.
This patch adds this transform and some related logic to InstructionSimplify
and removes some of the logic from instcombine (unfortunately not all because
there are several situations in which instcombine can improve things by making
new instructions, whereas instsimplify is not allowed to do this). At -O2 this
often results in more than 15% more simplifications by early-cse, and results in
hundreds of lines of bitcode being eliminated from the testsuite. I did see some
small negative effects in the testsuite, for example a few additional instructions
in three programs. One program, 483.xalancbmk, got an additional 35 instructions,
which seems to be due to a function getting an additional instruction and then
being inlined all over the place.
llvm-svn: 123911
by indvars through the scev expander.
trunc(add x, y) --> add(trunc x, y). Currently SCEV largely folds the other way
which is probably wrong, but preserved to minimize churn. Instcombine doesn't
do this fold either, demonstrating a missed optz'n opportunity on code doing
add+trunc+add.
llvm-svn: 123838
are pointing to the same object, one pointer is accessing the entire
object, and the other is access has a non-zero size. This prevents
TBAA from kicking in and saying NoAlias in such cases.
llvm-svn: 123775
These were not recommended by my auto-simplifier since they don't fire often enough.
However they do fire from time to time, for example they remove one subtraction from
the final bitcode for 483.xalancbmk.
llvm-svn: 123755
simplification in fully optimized code. It occurs sporadically in the testsuite, and
many times in 403.gcc: the final bitcode has 131 fewer subtractions after this change.
The reason that the multiplies are not eliminated is the same reason that instcombine
did not catch this: they are used by other instructions (instcombine catches this with
a more general transform which in general is only profitable if the operands have only
one use).
llvm-svn: 123754
half a million non-local queries, each of which would otherwise have triggered a
linear scan over a basic block.
Also fix a fixme for memory intrinsics which dereference pointers. With this,
we prove that a pointer is non-null because it was dereferenced by an intrinsic
112 times in llvm-test.
llvm-svn: 123533
simplification present in fully optimized code (I think instcombine fails to
transform some of these when "X-Y" has more than one use). Fires here and
there all over the test-suite, for example it eliminates 8 subtractions in
the final IR for 445.gobmk, 2 subs in 447.dealII, 2 in paq8p etc.
llvm-svn: 123442
threading of shifts over selects and phis while there. This fires here and
there in the testsuite, to not much effect. For example when compiling spirit
it fires 5 times, during early-cse, resulting in 6 more cse simplifications,
and 3 more terminators being folded by jump threading, but the final bitcode
doesn't change in any interesting way: other optimizations would have caught
the opportunity anyway, only later.
llvm-svn: 123441
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.
llvm-svn: 123417
Add methods for accessing the (single) entry / exit edge of a region. If no such
edge exists, null is returned. Both accessors return the start block of the
corresponding edge. The edge can finally be formed by utilizing
Region::getEntry() or Region::getExit();
Contributed by: Andreas Simbuerger <simbuerg@fim.uni-passau.de>
llvm-svn: 123410
is "X != 0 -> X" when X is a boolean. This occurs a lot because of the way
llvm-gcc converts gcc's conditional expressions. Add this, and a few other
similar transforms for completeness.
llvm-svn: 123372
point values to their integer representation through the SSE intrinsic
calls. This is the last part of a README.txt entry for which I have real
world examples.
llvm-svn: 123206
void f(int* begin, int* end) { std::fill(begin, end, 0); }
which turns into a != exit expression where one pointer is
strided and (thanks to step #1) known to not overflow, and
the other is loop invariant.
The observation here is that, though the IV is strided by
4 in this case, that the IV *has* to become equal to the
end value. It cannot "miss" the end value by stepping over
it, because if it did, the strided IV expression would
eventually wrap around.
Handle this by turning A != B into "A-B != 0" where the A-B
part is known to be NUW.
llvm-svn: 123131
ret i64 ptrtoint (i8* getelementptr ([1000 x i8]* @X, i64 1, i64 sub (i64 0, i64 ptrtoint ([1000 x i8]* @X to i64))) to i64)
to "ret i64 1000". This allows us to correctly compute the trip count
on a loop in PR8883, which occurs with std::fill on a char array. This
allows us to transform it into a memset with a constant size.
llvm-svn: 122950
a pointer value has potentially become escaping. Implementations can choose to either fall back to
conservative responses for that value, or may recompute their analysis to accomodate the change.
llvm-svn: 122777
update a callGraph when performing the common operation of splicing the body to
a new function and updating all callers (such as via RAUW).
No users yet, though this is intended for DeadArgumentElimination as part of
PR8887.
llvm-svn: 122728
numbering, in which it considers (for example) "%a = add i32 %x, %y" and
"%b = add i32 %x, %y" to be equal because the operands are equal and the
result of the instructions only depends on the values of the operands.
This has almost no effect (it removes 4 instructions from gcc-as-one-file),
and perhaps slows down compilation: I measured a 0.4% slowdown on the large
gcc-as-one-file testcase, but it wasn't statistically significant.
llvm-svn: 122654
the original instruction, half the cases were missed (making it not
wrong but suboptimal). Also correct a typo (A <-> B) in the second
chunk.
llvm-svn: 122414
a couple of existing transforms. This fires surprisingly often, for
example when compiling gcc "(X+(-1))+1->X" fires quite a lot as well
as various "and" simplifications (usually with a phi node operand).
Most of the time this doesn't make a real difference since the same
thing would have been done elsewhere anyway, eg: by instcombine, but
there are a few places where this results in simplifications that we
were not doing before.
llvm-svn: 122326
(they had just been forgotten before). Adding Xor causes "main" in the
existing testcase 2010-11-01-lshr-mask.ll to be hugely more simplified.
llvm-svn: 122245
While LLVM's main design is that analysis code shouldn't
go out of its way to understand code which hasn't been
InstCombined, analysis utility routines like this can
find themselves being called in the middle of transform
passes when instcombine hasn't had a chance to run.
llvm-svn: 121886
* mergeIn now uses constant folding for constants that are provably not-equal.
* sink some sanity checks from the get*() methods into the mark*() methods, to ensure that we never have a constant/notconstant ConstantInt
* some textual cleanups, whitespace changes, removing "else" after return, that sort of thing.
llvm-svn: 121877
it to be replaced by undef rather than not replaced at all, the idea being that
this may reduce the amount of work done by whoever called InstructionSimplify.
llvm-svn: 121860
zextOrTrunc(), and APSInt methods extend(), extOrTrunc() and new method
trunc(), to be const and to return a new value instead of modifying the
object in place.
llvm-svn: 121120
contains "ref".
Enhance DSE to use a modref query instead of a store-specific hack
to generalize the "ignore may-alias stores" optimization to handle
memset and memcpy.
llvm-svn: 120368
uninitialized. The warning is terrible, has incorrect source locations, and has
a huge false positive rate such as *all* of these.
If anyone has a better solution, please let me know. Alternatively, I'll
happily add -Wno-uninitialized to the -Werror build mode. Maybe I can even do
it *only* when building with GCC instead of Clang.
llvm-svn: 120281
are constant. There was in fact one exception to this (phi nodes) - so
remove that exception (InstructionSimplify handles this so there should
be no loss).
llvm-svn: 120015
folding improvements: if P points to a type of size zero, turn "gep P, N" into "P".
More generally, if a gep index type has size zero, instcombine could replace the
index with zero, but that is not done here.
llvm-svn: 119942
destination location of a memcpy/memmove. I'm not clear about whether
TBAA works on these, so I'm leaving it out for now. Dan, please revisit
this when convenient.
llvm-svn: 119928
preserves LCSSA form out of ScalarEvolution and into the LoopInfo
class. Use it to check that SimplifyInstruction simplifications
are not breaking LCSSA form. Fixes PR8622.
llvm-svn: 119727
needs to be checked that this won't break LCSSA form.
Change the existing checking method to a more direct one:
rather than seeing if all predecessors belong to the loop,
check that the replacing value is either not in any loop or
is in a loop that contains the phi node.
llvm-svn: 119556
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.
llvm-svn: 119536
simplified to itself (this can only happen in unreachable blocks).
Change it to return null instead. Hopefully this will fix some
buildbot failures.
llvm-svn: 119490
class, uses DominatorTree which is an analysis. This change moves all of
the tricky hasConstantValue logic to SimplifyInstruction, and replaces it
with a very simple literal implementation. I already taught users of
hasConstantValue that need tricky stuff to use SimplifyInstruction instead.
I didn't update InlineFunction because the IR looks like it might be in a
funky state at the point it calls hasConstantValue, which makes calling
SimplifyInstruction dangerous since it can in theory do a lot of tricky
reasoning. This may be a pessimization, for example in the case where
all phi node operands are either undef or a fixed constant.
llvm-svn: 119459
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.
llvm-svn: 119347
offload the work to hasConstantValue rather than do something more
complicated (such handling mutually recursive phis) because (1) it is
not clear it is worth it; and (2) if it is worth it, maybe such logic
would be better placed in hasConstantValue. Adjust some GVN tests
which are now cleaned up much further (eg: all phi nodes are removed).
llvm-svn: 119043
operands are the phi node itself or undef, then return undef.
This logic already existed at a higher level so in practice it
shouldn't make the slightest difference. Note that this code
could be replaced by a call to PN->hasConstantValue(). However
since we bail out the moment we see a non-constant operand, it
is more efficient to have a specialized version of that logic.
llvm-svn: 119041
references. For example, this allows gvn to eliminate the load in
this example:
void foo(int n, int* p, int *q) {
p[0] = 0;
p[1] = 1;
if (n) {
*q = p[0];
}
}
llvm-svn: 118714
nodes can be used in loops, this could result in infinite looping
if there is no recursion limit, so add such a limit. It is also
used for the SelectInst case because in theory there could be an
infinite loop there too if the basic block is unreachable.
llvm-svn: 118694
The simplifications performed here never create new instructions, they
only return existing instructions (or a constant), and so are always a
win. In theory they should transform (for example)
%z = and i32 %x, %y
%s = select i1 %cond, i32 %y, i32 %z
%r = and i32 %x, %s
into
%r = and i32 %x, y
but in practice they get into a fight with instcombine, and lose.
Unfortunately instcombine does a poor job in this case. Nonetheless
I'm committing this transform to make it easier to discuss what to
do to make peace with instcombine.
llvm-svn: 118679
to optionally look for constant or local (alloca) memory.
Teach BasicAliasAnalysis::pointsToConstantMemory to look through Select
and Phi nodes, and to support looking for local memory.
Remove FunctionAttrs' PointsToLocalOrConstantMemory function, now that
AliasAnalysis knows all the tricks that it knew.
llvm-svn: 118412
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.
llvm-svn: 118378
To create debugging information for a pointer, using DIBUilder front-end just needs
DBuilder.CreatePointerType(Ty, Size);
instead of
DebugFactory.CreateDerivedType(llvm::dwarf::DW_TAG_pointer_type,
TheCU, "", getOrCreateMainFile(),
0, Size, 0, 0, 0, OCTy);
llvm-svn: 118248
A RegionPass is executed like a LoopPass but on the regions detected by the
RegionInfo pass instead of the loops detected by the LoopInfo pass.
llvm-svn: 116905
must be called in the pass's constructor. This function uses static dependency declarations to recursively initialize
the pass's dependencies.
Clients that only create passes through the createFooPass() APIs will require no changes. Clients that want to use the
CommandLine options for passes will need to manually call the appropriate initialization functions in PassInitialization.h
before parsing commandline arguments.
I have tested this with all standard configurations of clang and llvm-gcc on Darwin. It is possible that there are problems
with the static dependencies that will only be visible with non-standard options. If you encounter any crash in pass
registration/creation, please send the testcase to me directly.
llvm-svn: 116820
does normal initialization and normal chaining. Change the default
AliasAnalysis implementation to NoAlias.
Update StandardCompileOpts.h and friends to explicitly request
BasicAliasAnalysis.
Update tests to explicitly request -basicaa.
llvm-svn: 116720
logic to use the new APInt methods. Among other things this
implements rdar://8501501 - llvm.smul.with.overflow.i32 should constant fold
which comes from "clang -ftrapv", originally brought to my attention from PR8221.
llvm-svn: 116457
getExpandedRegion() enables us to create non canonical regions. Those regions
can be used to define the largerst region, that fullfills a certain property.
llvm-svn: 116397
perform initialization without static constructors AND without explicit initialization
by the client. For the moment, passes are required to initialize both their
(potential) dependencies and any passes they preserve. I hope to be able to relax
the latter requirement in the future.
llvm-svn: 116334
Usually we wouldn't do this anyway because llvm_fenv_testexcept would return an
exception, but we have seen some cases where neither errno nor fenv detect an
exception on arm-linux.
llvm-svn: 114893
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.
llvm-svn: 114117
a Constant into a ConstantRange. Handle this conservatively for now, rather than asserting. The testcase is
more complex that I would like, but the manifestation of the problem is sensitive to iteration orders and the state of the
LVI cache, and I have not been able to reproduce it with manually constructed or simplified cases.
Fixes PR8162.
llvm-svn: 114103
isn't a good level of abstraction for memdep. Instead, generalize
AliasAnalysis::alias and related interfaces with a new Location
class for describing a memory location. For now, this is the same
Pointer and Size as before, plus an additional field for a TBAA tag.
Also, introduce a fixed MD_tbaa metadata tag kind.
llvm-svn: 113858
not unrolling loops that contain calls that would be better off getting inlined. This mostly
comes up when an interleaved devirtualization pass has devirtualized a call which the inliner
will inline on a future pass. Thus, rather than blocking all loops containing calls, add
a metric for "inline candidate calls" and block loops containing those instead.
llvm-svn: 113535
don't use any InlineCostAnalyzer state, and are useful for other clients who don't necessarily want to use
all of InlineCostAnalyzer's logic, some of which is fairly inlining-specific.
No intended functionality change.
llvm-svn: 113499
AliasAnalysis, and some code for implementing the new query on top of
existing implementations by making standard alias and getModRefInfo
queries.
llvm-svn: 113329
Loop::hasLoopInvariantOperands method. Remove
a useless and confusing Loop::isLoopInvariant(Instruction)
method, which didn't do what you thought it did.
No functionality change.
llvm-svn: 113133
invertible. ScalarEvolution's folding routines don't always succeed
in canonicalizing equal expressions to a single canonical form, and
this can cause these asserts to fail, even though there's no actual
correctness problem. This fixes PR8066.
llvm-svn: 113021
Unfortunately, the only testcase I have for this is huge and doesn't reduce well because the error is
sensitive to iteration-order issues, since the problem only occurs when merging values in a particular order.
llvm-svn: 112489
assertingvh so we get a violent explosion if the pointer dangles.
2) Fix AliasSetTracker::deleteValue to remove call sites with
by-pointer comparisons instead of by-alias queries. Using
findAliasSetForCallSite can cause alias sets to get merged
when they shouldn't, and can also miss alias sets when the
call is readonly.
#2 fixes PR6889, which only repros with a .c file :(
llvm-svn: 112452
of the sets is volatile. We were dropping the volatile bit of the
merged in set, leading (luckily) to assertions in cases like
PR7535. I cannot produce a testcase that repros with opt, but this
is obviously correct.
llvm-svn: 112402
transformation collect all the addrecs with the same loop
add combine them at once rather than starting everything over
at the first chance.
llvm-svn: 112290
not part of the IR, are not uniqued, and may be safely RAUW'd.
This replaces a variety of alternate mechanisms for achieving
the same effect.
llvm-svn: 111681
using a pair. This tidies up the code a bit. While setting things up, add
a (currently unused) field to keep track of how the value is extended.
llvm-svn: 111444
where the step value is an induction variable from an outer loop, to
avoid trouble trying to re-expand such expressions. This effectively
hides such expressions from indvars and lsr, which prevents them
from getting into trouble.
llvm-svn: 111317
a Pass abstraction, since that's the level it's actually used at.
Rename Pass' dumpPassStructure to dumpPass.
This eliminates an awkward use of getAsPass() to convert a PMDataManager*
into a Pass* just to permit a dumpPassStructure call.
llvm-svn: 111199
middle, copy the elements in two groups, rather than copying all the
elements and then doing an erase on the middle of the result. These
are SmallVectors, so we shouldn't expect to hit dynamic allocation
in the common case.
llvm-svn: 111151
having it finish processing all of the muliply operands before
starting the whole getAddExpr process over again, instead of
immediately after the first simplification.
llvm-svn: 110916
by having it finish processing the whole operand list before
starting the whole getAddExpr process over again, instead of
immediately after the first duplicate is found.
llvm-svn: 110914
AliasAnalysis base class and into BasicAliasAnalyais. This avoids confusion
about where such logic is happening when there are other AliasAnalysis
implementations present.
Move the logic for translating two-callsite getModRefInfo queries into
other AliasAnalysis queries out of BasicAliasAnalysis and into the
AliasAnalysis base class, as it is useful for other AliasAnalysis
implementations.
llvm-svn: 110421
response from getModRefInfo is not useful here. Instead, check for identical
calls only in the NoModRef case.
Reapply r110270, and strengthen it to compensate for the memdep changes.
When both calls are readonly, there is no dependence between them.
llvm-svn: 110382
to return Ref if the left callsite only reads memory read or written
by the right callsite; fix BasicAliasAnalysis to implement this.
Add AliasAnalysisEvaluator support for testing the two-callsite
form of getModRefInfo.
llvm-svn: 110270
eliminate several const_casts.
Make CallSite implicitly convertible to ImmutableCallSite.
Rename the getModRefBehavior for intrinsic IDs to
getIntrinsicModRefBehavior to avoid overload ambiguity with CallSite,
which happens to be implicitly convertible to bool.
llvm-svn: 110155
of Value deletions and RAUWs, instead of relying on ScalarEvolution's
Scalars map being notified, as that's complicated at best, and
insufficient in general.
This means SCEVUnknown needs a non-trivial destructor, so introduce
a mechanism to allow ScalarEvolution to locate all the SCEVUnknowns.
llvm-svn: 110086
extend it to handle the case where multiple RAUWs affect a single
SCEVUnknown.
Add a ScalarEvolution unittest to test for this situation.
llvm-svn: 109705
object, as it may still be referenced by SCEVs not cleaned up by the
use list traversal.
Also, in ScalarEvolution::forgetValue, only check for a SCEVUnknown
object for the original value, not for any value in the use list,
because other SCEVUnknown values aren't necessary obsolete at that
point.
llvm-svn: 109570
it inserted rather than using LoopInfo::getCanonicalInductionVariable to
rediscover it, since that doesn't work on non-canonical loops. This fixes
infinite recurrsion on such loops; PR7562.
llvm-svn: 109419
The RegionInfo pass detects single entry single exit regions in a function,
where a region is defined as any subgraph that is connected to the remaining
graph at only two spots.
Furthermore an hierarchical region tree is built.
Use it by calling "opt -regions analyze" or "opt -view-regions".
llvm-svn: 109089
Make MDNode::destroy private.
Fix the one thing that used MDNode::destroy, outside of MDNode itself.
One should never delete or destroy an MDNode explicitly. MDNodes
implicitly go away when there are no references to them (implementation
details aside).
llvm-svn: 109028
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.
llvm-svn: 108415
that was actually useful here.
Chris, please double check that this is the correct interpretation. I was
pretty sure, and ran it by Nick as well.
llvm-svn: 108129
interface needs implementations to be consistent, so any code which
wants to support different semantics must use a different interface.
It's not currently worthwhile to add a new interface for this new
concept.
Document that AliasAnalysis doesn't support cross-function queries.
llvm-svn: 107776
entries associated with the value being erased in the
folding set map. These entries used to be harmless, because
a SCEVUnknown doesn't store any information about its Value*,
so having a new Value allocated at the old Value's address
wasn't a problem. But now that ScalarEvolution is storing more
information about values, this is no longer safe.
llvm-svn: 107316
on ScalarEvolution successfully folding and preserving
range information for both A-B and B-A. Now, if it gets
either one, it's sufficient.
llvm-svn: 107249
instruction to an add scev, it's not safe to blindly transfer the
inbounds flag from a gep instruction to an nsw on the scev for the
gep.
llvm-svn: 107117
Devang Patel