Summary:
This change moves creating calls to `llvm.uadd.with.overflow` from
InstCombine to CodeGenPrep. Combining overflow check patterns into
calls to the said intrinsic in InstCombine inhibits optimization because
it introduces an intrinsic call that not all other transforms and
analyses understand.
Depends on D8888.
Reviewers: majnemer, atrick
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D8889
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234638 91177308-0d34-0410-b5e6-96231b3b80d8
CallSite roughly behaves as a common base CallInst and InvokeInst. Bring
the behavior closer to that model by making upcasts explicit. Downcasts
remain implicit and work as before.
Following dyn_cast as a mental model checking whether a Value *V isa
CallSite now looks like this:
if (auto CS = CallSite(V)) // think dyn_cast
instead of:
if (CallSite CS = V)
This is an extra token but I think it is slightly clearer. Making the
ctor explicit has the advantage of not accidentally creating nullptr
CallSites, e.g. when you pass a Value * to a function taking a CallSite
argument.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234601 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This patch adds an enum `OverflowCheckFlavor` and a function
`OptimizeOverflowCheck`. This will allow InstCombine to optimize
overflow checks without directly introducing an intermediate call to the
`llvm.$op.with.overflow` instrinsics.
This specific change is a refactoring and does not intend to change
behavior.
Reviewers: majnemer, atrick
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D8888
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234388 91177308-0d34-0410-b5e6-96231b3b80d8
InstCombine didn't realize that it needs to use DataLayout to determine
how wide pointers are. This lead to assertion failures.
This fixes PR23113.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234046 91177308-0d34-0410-b5e6-96231b3b80d8
This pushes the use of PointerType::getElementType up into several
callers - I'll essentially just have to keep pushing that up the stack
until I can eliminate every call to it...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233604 91177308-0d34-0410-b5e6-96231b3b80d8
This just didn't need to be here at all, but the assertion I tried to
add wasn't appropriate either - the circumstance isn't impossible, it's
just not important to deal with it here - the gep-rooted version of this
instcombine will handle this case, we don't need to duplicate it for the
case where the gep happens to be used in a bitcast.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233404 91177308-0d34-0410-b5e6-96231b3b80d8
Anding and comparing with zero can be done in a single instruction on
most archs so this is a bit cheaper.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233291 91177308-0d34-0410-b5e6-96231b3b80d8
The changes to InstCombine (& SCEV) do seem a bit silly - it doesn't make
anything obviously better to have the caller access the pointers element
type (the thing I'm trying to remove) than the GEP itself, but it's a
helpful migration step. This will allow me to more obviously lock down
GEP (& Load, etc) API usage, then fix all the code that accesses pointer
element types except the places that need to be removed (most of the
InstCombines) anyway - at which point I'll need to just remove all that
code because it won't be meaningful anymore (there will be no pointer
types, so no bitcasts to combine)
SCEV looks like it'll need some restructuring - we'll have to do a bit
more work for GEP canonicalization, since it'll depend on how it's used
if we can even manage to canonicalize it to a non-ugly GEP. I guess we
can do some fun stuff like voting (do 2 out of 3 load from the GEP with
a certain type that gives a pretty GEP? Does every typed use of the GEP
use either a specific type or a generic type (i8*, etc)?)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233131 91177308-0d34-0410-b5e6-96231b3b80d8
The changes to InstCombine do seem a bit silly - it doesn't make
anything obviously better to have the caller access the pointers element
type (the thing I'm trying to remove) than the GEP itself, but it's a
helpful migration step. This will allow me to more obviously lock down
GEP (& Load, etc) API usage, then fix all the code that accesses pointer
element types except the places that need to be removed (most of the
InstCombines) anyway - at which point I'll need to just remove all that
code because it won't be meaningful anymore (there will be no pointer
types, so no bitcasts to combine)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233126 91177308-0d34-0410-b5e6-96231b3b80d8
Assert that this doesn't fire - I'll remove all of this later, but just
leaving it in for a while in case this is firing & we just don't have
test coverage.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233116 91177308-0d34-0410-b5e6-96231b3b80d8
This is the IR optimizer follow-on patch for D8563: the x86 backend patch
that converts this kind of shuffle back into a vperm2.
This is also a continuation of the transform that started in D8486.
In that patch, Andrea suggested that we could convert vperm2 intrinsics that
use zero masks into a single shuffle.
This is an implementation of that suggestion.
Differential Revision: http://reviews.llvm.org/D8567
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233110 91177308-0d34-0410-b5e6-96231b3b80d8
vperm2* intrinsics are just shuffles.
In a few special cases, they're not even shuffles.
Optimizing intrinsics in InstCombine is better than
handling this in the front-end for at least two reasons:
1. Optimizing custom-written SSE intrinsic code at -O0 makes vector coders
really angry (and so I have regrets about some patches from last week).
2. Doing mask conversion logic in header files is hard to write and
subsequently read.
There are a couple of TODOs in this patch to complete this optimization.
Differential Revision: http://reviews.llvm.org/D8486
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@232852 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This change splits `makeICmpRegion` into `makeAllowedICmpRegion` and
`makeSatisfyingICmpRegion` with slightly different contracts. The first
one is useful for determining what values some expression //may// take,
given that a certain `icmp` evaluates to true. The second one is useful
for determining what values are guaranteed to //satisfy// a given
`icmp`.
Reviewers: nlewycky
Reviewed By: nlewycky
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D8345
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@232575 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: This is a first step toward getting proper support for aggregate loads and stores.
Test Plan: Added unittests
Reviewers: reames, chandlerc
Reviewed By: chandlerc
Subscribers: majnemer, joker.eph, chandlerc, llvm-commits
Differential Revision: http://reviews.llvm.org/D7780
Patch by Amaury Sechet
From: Mehdi Amini <mehdi.amini@apple.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@232284 91177308-0d34-0410-b5e6-96231b3b80d8
Adding nullptr to all the IRBuilder stuff because it's the first thing
that fails to build when testing without the back-compat functions, so
I'll keep having to re-add these locally for each chunk of migration I
do. Might as well check them in to save me the churn. Eventually I'll
have to migrate these too, but I'm going breadth-first.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@232270 91177308-0d34-0410-b5e6-96231b3b80d8
I'm just going to migrate these in a pretty ad-hoc & incremental way -
providing the backwards compatible API for now, then locally removing
it, fixing a few callers, adding it back in and commiting those callers.
Rinse, repeat.
The assertions should ensure that if I get this wrong we'll find out
about it and not just have one giant patch to revert, recommit, revert,
recommit, etc.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@232240 91177308-0d34-0410-b5e6-96231b3b80d8
As a follow-up to r232200, add an `-instcombine` to canonicalize scalar
allocations to `i32 1`. Since r232200, `iX 1` (for X != 32) are only
created by RAUWs, so this shouldn't fire too often. Nevertheless, it's
a cheap check and a nice cleanup.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@232202 91177308-0d34-0410-b5e6-96231b3b80d8
Move type promotion of the size of the array allocation to the end of
`simplifyAllocaArraySize()`. This avoids promoting the type of the
array size if it's a `ConstantInt`, since the next -instcombine
iteration will drop it to a scalar allocation anyway. Similarly, this
avoids promoting the type if it's an `UndefValue`, in which case the
alloca gets RAUW'ed.
This is NFC when considered over the lifetime of -instcombine, since
it's just reducing the number of iterations needed to reach fixed point.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@232201 91177308-0d34-0410-b5e6-96231b3b80d8
Write the `alloca` array size explicitly when it's non-canonical.
Previously, if the array size was `iX 1` (where X is not 32), the type
would mutate to `i32` when round-tripping through assembly.
The testcase I added fails in `verify-uselistorder` (as well as
`FileCheck`), since the use-lists for `i32 1` and `i64 1` change.
(Manman Ren came across this when running `verify-uselistorder` on some
non-trivial, optimized code as part of PR5680.)
The type mutation started with r104911, which allowed array sizes to be
something other than an `i32`. Starting with r204945, we
"canonicalized" to `i64` on 64-bit platforms -- and then on every
round-trip through assembly, mutated back to `i32`.
I bundled a fixup for `-instcombine` to avoid r204945 on scalar
allocations. (There wasn't a clean way to sequence this into two
commits, since the assembly change on its own caused testcase churn, and
the `-instcombine` change can't be tested without the assembly changes.)
An obvious alternative fix -- change `AllocaInst::AllocaInst()`,
`AsmWriter` and `LLParser` to treat `intptr_t` as the canonical type for
scalar allocations -- was rejected out of hand, since this required
teaching them each about the data layout.
A follow-up commit will add an `-instcombine` to canonicalize the scalar
allocation array size to `i32 1` rather than leaving `iX 1` alone.
rdar://problem/20075773
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@232200 91177308-0d34-0410-b5e6-96231b3b80d8
Follow-up commits will change some of the logic here. Splitting into a
separate function simplifies the logic by allowing early returns instead
of deeper nesting.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@232197 91177308-0d34-0410-b5e6-96231b3b80d8
Given that large parts of inst combine is restricted to instructions which have one use, getting rid of a use on the condition can help the effectiveness of the optimizer. Also, it allows the condition to potentially be deleted by instcombine rather than waiting for another pass.
I noticed this completely by accident in another test case. It's not anything that actually came from a real workload.
p.s. We should probably do the same thing for switch instructions.
Differential Revision: http://reviews.llvm.org/D8220
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231881 91177308-0d34-0410-b5e6-96231b3b80d8
ReplaceInstUsesWith needs to return nullptr when the input has no users,
because in that case it does not mutate the program. Otherwise, we can
get stuck in an infinite loop of repeatedly attempting to constant fold
and instruction with no users.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231755 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Now that the DataLayout is a mandatory part of the module, let's start
cleaning the codebase. This patch is a first attempt at doing that.
This patch is not exactly NFC as for instance some places were passing
a nullptr instead of the DataLayout, possibly just because there was a
default value on the DataLayout argument to many functions in the API.
Even though it is not purely NFC, there is no change in the
validation.
I turned as many pointer to DataLayout to references, this helped
figuring out all the places where a nullptr could come up.
I had initially a local version of this patch broken into over 30
independant, commits but some later commit were cleaning the API and
touching part of the code modified in the previous commits, so it
seemed cleaner without the intermediate state.
Test Plan:
Reviewers: echristo
Subscribers: llvm-commits
From: Mehdi Amini <mehdi.amini@apple.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231740 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
DataLayout keeps the string used for its creation.
As a side effect it is no longer needed in the Module.
This is "almost" NFC, the string is no longer
canonicalized, you can't rely on two "equals" DataLayout
having the same string returned by getStringRepresentation().
Get rid of DataLayoutPass: the DataLayout is in the Module
The DataLayout is "per-module", let's enforce this by not
duplicating it more than necessary.
One more step toward non-optionality of the DataLayout in the
module.
Make DataLayout Non-Optional in the Module
Module->getDataLayout() will never returns nullptr anymore.
Reviewers: echristo
Subscribers: resistor, llvm-commits, jholewinski
Differential Revision: http://reviews.llvm.org/D7992
From: Mehdi Amini <mehdi.amini@apple.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231270 91177308-0d34-0410-b5e6-96231b3b80d8
Selection conditions may be vectors or scalars. Make sure InstCombine
doesn't indiscriminately assume that a select which is value dependent
on another select have identical select condition types.
This fixes PR22773.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231156 91177308-0d34-0410-b5e6-96231b3b80d8
InstCombine has long had logic to convert aligned Altivec load/store intrinsics
into regular loads and stores. This mirrors that functionality for QPX vector
load/store intrinsics.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230660 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: SROA generates code that isn't quite as easy to optimize and contains unusual-sized shuffles, but that code is generally correct. As discussed in D7487 the right place to clean things up is InstCombine, which will pick up the type-punning pattern and transform it into a more obvious bitcast+extractelement, while leaving the other patterns SROA encounters as-is.
Test Plan: make check
Reviewers: jvoung, chandlerc
Subscribers: llvm-commits
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230560 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This change fixes the FIXME that you recently added when you committed
(a modified version of) my patch. When `InstCombine` combines a load and
store of an pointer to those of an equivalently-sized integer, it currently
drops any `!nonnull` metadata that might be present. This change replaces
`!nonnull` metadata with `!range !{ 1, -1 }` metadata instead.
Reviewers: chandlerc
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D7621
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230462 91177308-0d34-0410-b5e6-96231b3b80d8
This case is interesting because ScalarEvolutionExpander lowers min(a,
b) as ~max(~a,~b). I think the profitability heuristics can be made
more clever/aggressive, but this is a start.
Differential Revision: http://reviews.llvm.org/D7821
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230285 91177308-0d34-0410-b5e6-96231b3b80d8
This change addresses a deficiency pointed out in PR22629. To copy from the bug
report:
[from the bug report]
Consider this code:
int f(int x) {
int a[] = {12};
return a[x];
}
GCC knows to optimize this to
movl $12, %eax
ret
The code generated by recent Clang at -O3 is:
movslq %edi, %rax
movl .L_ZZ1fiE1a(,%rax,4), %eax
retq
.L_ZZ1fiE1a:
.long 12 # 0xc
[end from the bug report]
This definitely seems worth fixing. I've also seen this kind of code before (as
the base case of generic vector wrapper templates with one element).
The general idea is to look at the GEP feeding a load or a store, which has
some variable as its first non-zero index, and determine if that index must be
zero (or else an out-of-bounds access would occur). We can do this for allocas
and globals with constant initializers where we know the maximum size of the
underlying object. When we find such a GEP, we create a new one for the memory
access with that first variable index replaced with a constant zero.
Even if we can't eliminate the memory access (and sometimes we can't), it is
still useful because it removes unnecessary indexing calculations.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229959 91177308-0d34-0410-b5e6-96231b3b80d8
InstCombiner::visitGetElementPtrInst was using getFirstNonPHI to compute the
insertion point, which caused the verifier to complain when a GEP was inserted
before a landingpad instruction. This commit fixes it to use getFirstInsertionPt
instead.
rdar://problem/19394964
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229619 91177308-0d34-0410-b5e6-96231b3b80d8
The "dereferenceable" attribute cannot be added via .addAttribute(),
since it also expects a size in bytes. AttrBuilder#addAttribute or
AttributeSet#addAttribute is wrapped by classes Function, InvokeInst,
and CallInst. Add corresponding wrappers to
AttrBuilder#addDereferenceableAttr.
Having done this, propagate the dereferenceable attribute via
gc.relocate, adding a test to exercise it. Note that -datalayout is
required during execution over and above -instcombine, because
InstCombine only optionally requires DataLayoutPass.
Differential Revision: http://reviews.llvm.org/D7510
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229265 91177308-0d34-0410-b5e6-96231b3b80d8
