This commit extends the patterns recognised by InstSimplify to also handle (x >> y) <= x in the same way as (x /u y) <= x.
The missing optimisation was found investigating why LLVM did not optimise away bound checks in a binary search: https://github.com/rust-lang/rust/pull/30917
Patch by Andrea Canciani!
Differential Revision: http://reviews.llvm.org/D16402
llvm-svn: 258422
Summary:
And use it in PPCLoopDataPrefetch.cpp.
@hfinkel, please let me know if your preference would be to preserve the
ppc-loop-prefetch-cache-line option in order to be able to override the
value of TTI::getCacheLineSize for PPC.
Reviewers: hfinkel
Subscribers: hulx2000, mcrosier, mssimpso, hfinkel, llvm-commits
Differential Revision: http://reviews.llvm.org/D16306
llvm-svn: 258419
This undoes the change made in r258163. The assertion fails if `Ptr` is of a
vector type. The previous code doesn't look completely correct either, so I'll
investigate this more.
llvm-svn: 258411
Summary:
The previous form, taking opcode and type, is moved to an internal
helper and the new form, taking an instruction, is a wrapper around this
helper.
Although this is a slight cleanup on its own, the main motivation is to
refactor the constant folding API to ease migration to opaque pointers.
This will be follow-up work.
Reviewers: eddyb
Subscribers: dblaikie, llvm-commits
Differential Revision: http://reviews.llvm.org/D16383
llvm-svn: 258391
Summary:
Although this is a slight cleanup on its own, the main motivation is to
refactor the constant folding API to ease migration to opaque pointers.
This will be follow-up work.
Reviewers: eddyb
Subscribers: zzheng, dblaikie, llvm-commits
Differential Revision: http://reviews.llvm.org/D16380
llvm-svn: 258390
Summary:
Although this is a slight cleanup on its own, the main motivation is to
refactor the constant folding API to ease migration to opaque pointers.
This will be follow-up work.
Reviewers: eddyb
Subscribers: dblaikie, llvm-commits
Differential Revision: http://reviews.llvm.org/D16378
llvm-svn: 258389
In some cases, the max backedge taken count can be more conservative
than the exact backedge taken count (for instance, because
ScalarEvolution::getRange is not control-flow sensitive whereas
computeExitLimitFromICmp can be). In these cases,
computeExitLimitFromCond (specifically the bit that deals with `and` and
`or` instructions) can create an ExitLimit instance with a
`SCEVCouldNotCompute` max backedge count expression, but a computable
exact backedge count expression. This violates an implicit SCEV
assumption: a computable exact BE count should imply a computable max BE
count.
This change
- Makes the above implicit invariant explicit by adding an assert to
ExitLimit's constructor
- Changes `computeExitLimitFromCond` to be more robust around
conservative max backedge counts
llvm-svn: 258184
Summary:
GEPOperator: provide getResultElementType alongside getSourceElementType.
This is made possible by adding a result element type field to GetElementPtrConstantExpr, which GetElementPtrInst already has.
GEP: replace get(Pointer)ElementType uses with get{Source,Result}ElementType.
Reviewers: mjacob, dblaikie
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D16275
llvm-svn: 258145
It looks nicer and improves the compiletime of a typical
clang -O3 -emit-llvm run by ~0.6% for me.
Differential Revision: http://reviews.llvm.org/D16205
llvm-svn: 257944
Summary:
Rename to getCatchSwitchParentPad, to make it more clear which ancestor
the "parent" in question is. Add a comment pointing out the key feature
that the returned pad indicates which funclet contains the successor
block.
Reviewers: rnk, andrew.w.kaylor, majnemer
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D16222
llvm-svn: 257933
Some patterns of select+compare allow us to know exactly the value of the uppermost bits in the select result. For example:
%b = icmp ugt i32 %a, 5
%c = select i1 %b, i32 2, i32 %a
Here we know that %c is bounded by 5, and therefore KnownZero = ~APInt(5).getActiveBits() = ~7.
There are several such patterns, and this patch attempts to understand a reasonable subset of them - namely when the base values are the same (as above), and when they are related by a simple (add nsw), for example (add nsw %a, 4) and %a.
llvm-svn: 257769
Summary:
Since globals may escape as function arguments (even when they have been
found to be non-escaping, because of optimizations such as memcpyoptimizer
that replaces stores with memcpy), all arguments to a function are checked
during query to make sure they are identifiable. At that time, also ensure
we return a conservative result only if the arguments don't alias to our global.
Reviewers: hfinkel, jmolloy
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D16140
llvm-svn: 257750
It's strange that LoopInfo mostly owns the Loop objects, but that it
defers deleting them to the loop pass manager. Instead, change the
oddly named "updateUnloop" to "markAsRemoved" and have it queue the
Loop object for deletion. We can't delete the Loop immediately when we
remove it, since we need its pointer identity still, so we'll mark the
object as "invalid" so that clients can see what's going on.
llvm-svn: 257191
The early return seems to be missed. This causes a radical and wrong loop
optimization on powerpc. It isn't reproducible on x86_64, because
"UseInterleaved" is false.
Patch by Tim Shen.
llvm-svn: 257134
See PR25822 for a more full summary, but we were conflating the concepts of "capture" and "escape". We were proving nocapture and using that proof to infer noescape, which is not true. Escaped-ness is a function-local property - as soon as a value is used in a call argument it escapes. Capturedness is a related but distinct property. It implies a *temporally limited* escape. Consider:
static int a;
int b;
int g(int * nocapture arg);
int f() {
a = 2; // Even though a escapes to g, it is not captured so can be treated as non-escaping here.
g(&a); // But here it must be treated as escaping.
g(&b); // Now that g(&a) has returned we know it was not captured so we can treat it as non-escaping again.
}
The original commit did not sufficiently understand this nuance and so caused PR25822 and PR26046.
r248576 included both a performance improvement (which has been backed out) and a related conformance fix (which has been kept along with its testcase).
llvm-svn: 257058
Summary:
This patch implements "-print-funcs" option to support function filtering for IR printing like -print-after-all, -print-before etc.
Examples:
-print-after-all -print-funcs=foo,bar
Reviewers: mcrosier, joker.eph
Subscribers: tejohnson, joker.eph, llvm-commits
Differential Revision: http://reviews.llvm.org/D15776
llvm-svn: 256952
Since writeonly is the only missing attribute and special case left for the memset/memcpy family of intrinsics, rearrange the code to make that much more clear.
llvm-svn: 256949
Summary:
This reverts commit 5a9e526f29cf8510ab5c3d566fbdcf47ac24e1e9.
As per discussion in D15665
This also add a test case so that regression introduced by that diff are not reintroduced.
Reviewers: vaivaswatha, jmolloy, hfinkel, reames
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D15919
llvm-svn: 256932
Most of the properties of memset_pattern16 can be now covered by the generic attributes and inferred by InferFunctionAttrs. The only exceptions are:
- We don't yet have a writeonly attribute for the first argument.
- We don't have an attribute for modeling the access size facts encoded in MemoryLocation.cpp.
Differential Revision: http://reviews.llvm.org/D15879
llvm-svn: 256911
We only need to describe the writeonly property of one of the arguments. All of the rest of the semantics are nicely described by existing attributes in Intrinsics.td.
Differential Revision: http://reviews.llvm.org/D15880
llvm-svn: 256910
Summary:
This commit renames GCRelocateOperands to GCRelocateInst and makes it an
intrinsic wrapper, similar to e.g. MemCpyInst. Also, all users of
GCRelocateOperands were changed to use the new intrinsic wrapper instead.
Reviewers: sanjoy, reames
Subscribers: reames, sanjoy, llvm-commits
Differential Revision: http://reviews.llvm.org/D15762
llvm-svn: 256811
If we encounter a noalias call that alias analysis can't analyse, we can fall down into the generic call handling rather than giving up entirely. I noticed this while reading through the code for another purpose.
I can't seem to write a test case which changes; that sorta makes sense given any test case would have to be an inconsistency in AA. Suggestions welcome.
Differential Revision: http://reviews.llvm.org/D15825
llvm-svn: 256802
This patch removes the isOperatorNewLike predicate since it was only being used to establish a non-null return value and we have attributes specifically for that purpose with generic handling. To keep approximate the same behaviour for existing frontends, I added the various operator new like (i.e. instances of operator new) to InferFunctionAttrs. It's not really clear to me why this isn't handled in Clang, but I didn't want to break existing code and any subtle assumptions it might have.
Once this patch is in, I'm going to start separating the isAllocLike family of predicates. These appear to be being used for a mixture of things which should be more clearly separated and documented. Today, they're being used to indicate (at least) aliasing facts, CSE-ability, and default values from an allocation site.
Differential Revision: http://reviews.llvm.org/D15820
llvm-svn: 256787
Amazingly, we just never triggered this without:
1) Moving code around for MetadataTracking so that a certain *different*
amount of inlining occurs in the per-TU compile step.
2) Then you LTO opt or clang with a bootstrap, and get inlining, loop
opts, and GVN line up everything *just* right.
I don't really know how we didn't hit this before. We really need to be
fuzz testing stuff, it shouldn't be hard to trigger. I'm working on
crafting a reduced nice test case, and will submit that when I have it,
but I want to get LTO build bots going again.
llvm-svn: 256735
InlineCostAnalysis is an analysis pass without any need for it to be one.
Once it stops being an analysis pass, it doesn't maintain any useful state
and the member functions inside can be made free functions. NFC.
Differential Revision: http://reviews.llvm.org/D15701
llvm-svn: 256521
The cost is calculated for all X86 targets. When gather/scatter instruction
is not supported we calculate the cost of scalar sequence.
Differential revision: http://reviews.llvm.org/D15677
llvm-svn: 256519
The way `getLoopBackedgeTakenCounts` is written right now isn't
correct. It will try to compute and store the BE counts of a Loop
#{child loop} number of times (which may be zero).
llvm-svn: 256338
This reapplies r256277 with two changes:
- In emitFnAttrCompatCheck, change FuncName's type to std::string to fix
a use-after-free bug.
- Remove an unnecessary install-local target in lib/IR/Makefile.
Original commit message for r252949:
Provide a way to specify inliner's attribute compatibility and merging
rules using table-gen. NFC.
This commit adds new classes CompatRule and MergeRule to Attributes.td,
which are used to generate code to check attribute compatibility and
merge attributes of the caller and callee.
rdar://problem/19836465
llvm-svn: 256304
This reapplies r252990 and r252949. I've added member function getKind
to the Attr classes which returns the enum or string of the attribute.
Original commit message for r252949:
Provide a way to specify inliner's attribute compatibility and merging
rules using table-gen. NFC.
This commit adds new classes CompatRule and MergeRule to Attributes.td,
which are used to generate code to check attribute compatibility and
merge attributes of the caller and callee.
rdar://problem/19836465
llvm-svn: 256277
This patch removes all weight-related interfaces from BPI and replace
them by probability versions. With this patch, we won't use edge weight
anymore in either IR or MC passes. Edge probabilitiy is a better
representation in terms of CFG update and validation.
Differential revision: http://reviews.llvm.org/D15519
llvm-svn: 256263
This is recommit of r256028 with minor fixes in unittests:
CodeGen/Mips/eh.ll
CodeGen/Mips/insn-zero-size-bb.ll
Original commit message:
When identifying blocks post-dominated by an unreachable-terminated block
in BranchProbabilityInfo, consider only the edge to the normal destination
block if the terminator is InvokeInst and let calcInvokeHeuristics() decide
edge weights for the InvokeInst.
llvm-svn: 256202
When identifying blocks post-dominated by an unreachable-terminated block
in BranchProbabilityInfo, consider only the edge to the normal destination
block if the terminator is InvokeInst and let calcInvokeHeuristics() decide
edge weights for the InvokeInst.
llvm-svn: 256028
Summary:
1. Modify AnalyzeCallGraph() to retain function info for external functions
if the function has [InaccessibleMemOr]ArgMemOnly flags.
2. When analyzing the use of a global is function parameter at a call site,
mark the callee also as modifying the global appropriately.
3. Add additional test cases.
Depends on D15499
Reviewers: hfinkel, jmolloy
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D15605
llvm-svn: 255994
Clang has better diagnostics in this case. It is not necessary therefore
to change the destructor to avoid what is effectively an invalid warning
in gcc. Instead, better handle the warning flags given to the compiler.
llvm-svn: 255905
As of r255720, the loop pass manager will DTRT when passes update the
loop info for removed loops, so they no longer need to reach into
LPPassManager APIs to do this kind of transformation. This change very
nearly removes the need for the LPPassManager to even be passed into
loop passes - the only remaining pass that uses the LPM argument is
LoopUnswitch.
llvm-svn: 255797
When a pass removes a loop it currently has to reach up into the
LPPassManager's internals to update the state of the iteration over
loops. This reverse dependency results in a pretty awkward interplay
of the LPPassManager and its Passes.
Here, we change this to instead keep track of when a loop has become
"unlooped" in the Loop objects themselves, then the LPPassManager can
check this and manipulate its own state directly. This opens the door
to allow most of the loop passes to work without a backreference to
the LPPassManager.
I've kept passes calling the LPPassManager::deleteLoopFromQueue API
now so I could put an assert in to prove that this is NFC, but a later
pass will update passes just to preserve the LoopInfo directly and
stop referencing the LPPassManager completely.
llvm-svn: 255720
Summary:
The LibCallSimplifier will turn llvm.exp2.* intrinsics into ldexp* libcalls
which do not make sense with the AMDGPU backend.
In the long run, we'll want an llvm.ldexp.* intrinsic to properly make use of
this optimization, but this works around the problem for now.
See also: http://reviews.llvm.org/D14327 (suggested llvm.ldexp.* implementation)
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92709
Reviewers: arsenm, tstellarAMD
Differential Revision: http://reviews.llvm.org/D14990
llvm-svn: 255658
It turns out that terminatepad gives little benefit over a cleanuppad
which calls the termination function. This is not sufficient to
implement fully generic filters but MSVC doesn't support them which
makes terminatepad a little over-designed.
Depends on D15478.
Differential Revision: http://reviews.llvm.org/D15479
llvm-svn: 255522
While we have successfully implemented a funclet-oriented EH scheme on
top of LLVM IR, our scheme has some notable deficiencies:
- catchendpad and cleanupendpad are necessary in the current design
but they are difficult to explain to others, even to seasoned LLVM
experts.
- catchendpad and cleanupendpad are optimization barriers. They cannot
be split and force all potentially throwing call-sites to be invokes.
This has a noticable effect on the quality of our code generation.
- catchpad, while similar in some aspects to invoke, is fairly awkward.
It is unsplittable, starts a funclet, and has control flow to other
funclets.
- The nesting relationship between funclets is currently a property of
control flow edges. Because of this, we are forced to carefully
analyze the flow graph to see if there might potentially exist illegal
nesting among funclets. While we have logic to clone funclets when
they are illegally nested, it would be nicer if we had a
representation which forbade them upfront.
Let's clean this up a bit by doing the following:
- Instead, make catchpad more like cleanuppad and landingpad: no control
flow, just a bunch of simple operands; catchpad would be splittable.
- Introduce catchswitch, a control flow instruction designed to model
the constraints of funclet oriented EH.
- Make funclet scoping explicit by having funclet instructions consume
the token produced by the funclet which contains them.
- Remove catchendpad and cleanupendpad. Their presence can be inferred
implicitly using coloring information.
N.B. The state numbering code for the CLR has been updated but the
veracity of it's output cannot be spoken for. An expert should take a
look to make sure the results are reasonable.
Reviewers: rnk, JosephTremoulet, andrew.w.kaylor
Differential Revision: http://reviews.llvm.org/D15139
llvm-svn: 255422
reduce memory usage.
Previously, LazyValueInfoCache inserted overdefined lattice values into
both ValueCache and OverDefinedCache. This wasn't necessary and was
causing LazyValueInfo to use an excessive amount of memory in some cases.
This patch changes LazyValueInfoCache to insert overdefined values only
into OverDefinedCache. The memory usage decreases by 70 to 75% when one
of the files in llvm is compiled.
rdar://problem/11388615
Differential revision: http://reviews.llvm.org/D15391
llvm-svn: 255320
ScalarEvolution.h, in order to avoid cyclic dependencies between the Transform
and Analysis modules:
[LV][LAA] Add a layer over SCEV to apply run-time checked knowledge on SCEV expressions
Summary:
This change creates a layer over ScalarEvolution for LAA and LV, and centralizes the
usage of SCEV predicates. The SCEVPredicatedLayer takes the statically deduced knowledge
by ScalarEvolution and applies the knowledge from the SCEV predicates. The end goal is
that both LAA and LV should use this interface everywhere.
This also solves a problem involving the result of SCEV expression rewritting when
the predicate changes. Suppose we have the expression (sext {a,+,b}) and two predicates
P1: {a,+,b} has nsw
P2: b = 1.
Applying P1 and then P2 gives us {a,+,1}, while applying P2 and the P1 gives us
sext({a,+,1}) (the AddRec expression was changed by P2 so P1 no longer applies).
The SCEVPredicatedLayer maintains the order of transformations by feeding back
the results of previous transformations into new transformations, and therefore
avoiding this issue.
The SCEVPredicatedLayer maintains a cache to remember the results of previous
SCEV rewritting results. This also has the benefit of reducing the overall number
of expression rewrites.
Reviewers: mzolotukhin, anemet
Subscribers: jmolloy, sanjoy, llvm-commits
Differential Revision: http://reviews.llvm.org/D14296
llvm-svn: 255122
Summary:
This change creates a layer over ScalarEvolution for LAA and LV, and centralizes the
usage of SCEV predicates. The SCEVPredicatedLayer takes the statically deduced knowledge
by ScalarEvolution and applies the knowledge from the SCEV predicates. The end goal is
that both LAA and LV should use this interface everywhere.
This also solves a problem involving the result of SCEV expression rewritting when
the predicate changes. Suppose we have the expression (sext {a,+,b}) and two predicates
P1: {a,+,b} has nsw
P2: b = 1.
Applying P1 and then P2 gives us {a,+,1}, while applying P2 and the P1 gives us
sext({a,+,1}) (the AddRec expression was changed by P2 so P1 no longer applies).
The SCEVPredicatedLayer maintains the order of transformations by feeding back
the results of previous transformations into new transformations, and therefore
avoiding this issue.
The SCEVPredicatedLayer maintains a cache to remember the results of previous
SCEV rewritting results. This also has the benefit of reducing the overall number
of expression rewrites.
Reviewers: mzolotukhin, anemet
Subscribers: jmolloy, sanjoy, llvm-commits
Differential Revision: http://reviews.llvm.org/D14296
llvm-svn: 255115
Reduces the scope over which the struct is visible, making its usages
obvious. I did not move structs in cases where this wasn't a clear
win (the struct is too large, or is grouped in some other interesting
way).
llvm-svn: 255003
Summary:
Also add a stricter post-condition for IndVarSimplify.
Fixes PR25578. Test case by Michael Zolotukhin.
Reviewers: hfinkel, atrick, mzolotukhin
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D15059
llvm-svn: 254977
Summary:
(Note: the problematic invocation of hoistIVInc that caused PR24804 came
from IndVarSimplify, not from SCEVExpander itself)
Fixes PR24804. Test case by David Majnemer.
Reviewers: hfinkel, majnemer, atrick, mzolotukhin
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D15058
llvm-svn: 254976
Haicheng Wu