As suggested by Chandler in his review comments for D18662, this
follow-on patch renames some variables in GetLoadValueForLoad and
CoerceAvailableValueToLoadType to hopefully make it more obvious
which variables hold value sizes and which hold load/store sizes.
No functional change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265687 91177308-0d34-0410-b5e6-96231b3b80d8
When GVN wants to re-interpret an already available value in a smaller
type, it needs to right-shift the value on big-endian systems to ensure
the correct bytes are accessed. The shift value is the difference of
the sizes of the two types.
This is correct as long as both types occupy multiples of full bytes.
However, when one of them is a sub-byte type like i1, this no longer
holds true: we still need to shift, but only to access the correct
*byte*. Accessing bits within the byte requires no shift in either
endianness; e.g. an i1 resides in the least-significant bit of its
containing byte on both big- and little-endian systems.
Therefore, the appropriate shift value to be used is the difference of
the *storage* sizes of the two types. This is already handled correctly
in one place where such a shift takes place (GetStoreValueForLoad), but
is incorrect in two other places: GetLoadValueForLoad and
CoerceAvailableValueToLoadType.
This patch changes both places to use the storage size as well.
Differential Revision: http://reviews.llvm.org/D18662
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265684 91177308-0d34-0410-b5e6-96231b3b80d8
Remove the assertion that disallowed the combination, since
RF_IgnoreMissingLocals should have no effect on globals. As it happens,
RF_NullMapMissingGlobalValues asserted in MapValue(Constant*,...), so I
also changed a cast to a cast_or_null to get my test passing.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265633 91177308-0d34-0410-b5e6-96231b3b80d8
Start treating LocalAsMetadata similarly to function-local members of
the Value hierarchy in MapValue and MapMetadata.
- Don't memoize them.
- Return nullptr if they are missing.
This also cleans up ConstantAsMetadata to stop listening to the
RF_IgnoreMissingLocals flag.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265631 91177308-0d34-0410-b5e6-96231b3b80d8
Clarify what this RemapFlag actually means.
- Change the flag name to match its intended behaviour.
- Clearly document that it's not supposed to affect globals.
- Add a host of FIXMEs to indicate how to fix the behaviour to match
the intent of the flag.
RF_IgnoreMissingLocals should only affect the behaviour of
RemapInstruction for function-local operands; namely, for operands of
type Argument, Instruction, and BasicBlock. Currently, it is *only*
passed into RemapInstruction calls (and the transitive MapValue calls
that it makes).
When I split Metadata from Value I didn't understand the flag, and I
used it in a bunch of places for "global" metadata.
This commit doesn't have any functionality change, but prepares to
cleanup MapMetadata and MapValue.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265628 91177308-0d34-0410-b5e6-96231b3b80d8
Updating dominators for exit-blocks of the unrolled loops is not enough,
as shown in PR27157. The proper way is to update dominators for all
dominance-children of original loop blocks.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265605 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
In the context of http://wg21.link/lwg2445 C++ uses the concept of
'stronger' ordering but doesn't define it properly. This should be fixed
in C++17 barring a small question that's still open.
The code currently plays fast and loose with the AtomicOrdering
enum. Using an enum class is one step towards tightening things. I later
also want to tighten related enums, such as clang's
AtomicOrderingKind (which should be shared with LLVM as a 'C++ ABI'
enum).
This change touches a few lines of code which can be improved later, I'd
like to keep it as NFC for now as it's already quite complex. I have
related changes for clang.
As a follow-up I'll add:
bool operator<(AtomicOrdering, AtomicOrdering) = delete;
bool operator>(AtomicOrdering, AtomicOrdering) = delete;
bool operator<=(AtomicOrdering, AtomicOrdering) = delete;
bool operator>=(AtomicOrdering, AtomicOrdering) = delete;
This is separate so that clang and LLVM changes don't need to be in sync.
Reviewers: jyknight, reames
Subscribers: jyknight, llvm-commits
Differential Revision: http://reviews.llvm.org/D18775
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265602 91177308-0d34-0410-b5e6-96231b3b80d8
1. Add FullUnrollMaxCount option that works like MaxCount, but also limits
the unroll count for fully unrolled loops. So if a loop has an iteration
count over this, it won't fully unroll.
2. Add CLI options for MaxCount and the new option, so they can be tested
(plus a test).
3. Make partial unrolling obey MaxCount.
An example use-case (the out of tree one this is originally designed for) is
a target’s TTI can analyze a loop and decide on a max unroll count separate
from the size threshold, e.g. based on register pressure, then constrain
LoopUnroll to not exceed that, regardless of the size of the unrolled loop.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265562 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
When the backedge taken codition is computed from an icmp, SCEV can
deduce the backedge taken count only if one of the sides of the icmp
is an AddRecExpr. However, due to sign/zero extensions, we sometimes
end up with something that is not an AddRecExpr.
However, we can use SCEV predicates to produce a 'guarded' expression.
This change adds a method to SCEV to get this expression, and the
SCEV predicate associated with it.
In HowManyGreaterThans and HowManyLessThans we will now add a SCEV
predicate associated with the guarded backedge taken count when the
analyzed SCEV expression is not an AddRecExpr. Note that we only do
this as an alternative to returning a 'CouldNotCompute'.
We use new feature in Loop Access Analysis and LoopVectorize to analyze
and transform more loops.
Reviewers: anemet, mzolotukhin, hfinkel, sanjoy
Subscribers: flyingforyou, mcrosier, atrick, mssimpso, sanjoy, mzolotukhin, llvm-commits
Differential Revision: http://reviews.llvm.org/D17201
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265535 91177308-0d34-0410-b5e6-96231b3b80d8
r265273 added Mapper::mapBlockAddress, which delays mapping a
blockaddress value until the function has a body. The condition was
backwards, and should be checking Function::empty instead of
GlobalValue::isDeclaration.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265508 91177308-0d34-0410-b5e6-96231b3b80d8
Don't emit a gc.result for a statepoint lowered from
@llvm.experimental.deoptimize since the call into __llvm_deoptimize is
effectively noreturn. Instead follow the corresponding gc.statepoint
with an "unreachable".
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265485 91177308-0d34-0410-b5e6-96231b3b80d8
Add a common parent class for ConstantArray, ConstantVector, and
ConstantStruct called ConstantAggregate. These are the aggregate
subclasses of Constant that take operands.
This is mainly a cleanup, adding common `isa` target and removing
duplicated code. However, it also simplifies caching which constants
point transitively at `GlobalValue` (a possible future direction).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265466 91177308-0d34-0410-b5e6-96231b3b80d8
I can't remember if adding `= default` will make MSVC happy, or if I
have to spell this out. Let's try the cleaner version first.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265465 91177308-0d34-0410-b5e6-96231b3b80d8
This commit completely rewrites Mapper::mapMetadata (the implementation
of llvm::MapMetadata) using an iterative algorithm. The guts of the new
algorithm are in MDNodeMapper::map, the entry function in a new class.
Previously, Mapper::mapMetadata performed a recursive exploration of the
graph with eager "just in case there's a reason" malloc traffic.
The new algorithm has these benefits:
- New nodes and temporaries are not created eagerly.
- Uniquing cycles are not duplicated (see new unit test).
- No recursion.
Given a node to map, it does this:
1. Use a worklist to perform a post-order traversal of the transitively
referenced unmapped nodes.
2. Track which nodes will change operands, and which will have new
addresses in the mapped scheme. Propagate the changes through the
POT until fixed point, to pick up uniquing cycles that need to
change.
3. Map all the distinct nodes without touching their operands. If
RF_MoveDistinctMetadata, they get mapped to themselves; otherwise,
they get mapped to clones.
4. Map the uniqued nodes (bottom-up), lazily creating temporaries for
forward references as needed.
5. Remap the operands of the distinct nodes.
Mehdi helped me out by profiling this with -flto=thin. On his workload
(importing/etc. for opt.cpp), MapMetadata sped up by 15%, contributed
about 50% less to persistent memory, and made about 100x fewer calls to
malloc. The speedup is less than I'd hoped. The profile mainly blames
DenseMap lookups; perhaps there's a way to reduce them (e.g., by
disallowing remapping of MDString).
It would be nice to break the strange remaining recursion on the Value
side: MapValue => materializeInitFor => RemapInstruction => MapValue. I
think we could do this by having materializeInitFor return a worklist of
things to be remapped.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265456 91177308-0d34-0410-b5e6-96231b3b80d8
Direct callees' that are cast to other function prototypes,
show up in the Call/Invoke instructions as ConstantExpr's.
Currently llvm::CallSite's getCalledFunction() fails
to return the callees in such expressions as direct calls.
Value profiling should avoid instrumenting such cases. Mostly NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265330 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
To aid in debugging, dump out the correlation between value names and
GUID for each source module when it is materialized. This will make it
easier to comprehend the earlier summary-based function importing debug
trace which only has access to and prints the GUIDs.
Reviewers: joker.eph
Subscribers: llvm-commits, joker.eph
Differential Revision: http://reviews.llvm.org/D18556
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265326 91177308-0d34-0410-b5e6-96231b3b80d8
Remove a few old FIXMEs from the original commit of the Metadata/Value
split in r223802. These are commented out assertions to the effect that
calls between mapValue and mapMetadata never return nullptr.
(The only behaviour change is that Mapper::mapSimpleMetadata memoizes
the nullptr return.)
When I originally rewrote the mapping code, I thought we could be
stricter in the new metadata hierarchy and never return nullptr when
RF_NullMapMissingGlobalValues was off. It's still not entirely clear to
me why these assertions failed (a few months ago, I had a theory that I
forgot to write down, but that's helping no one).
Understood or not, I no longer see how these commented-out assertions
would be useful. I'm relegating them to the annals of source control
before making significant changes to ValueMapper.cpp.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265282 91177308-0d34-0410-b5e6-96231b3b80d8
This adds an assertion to maintain the property from r265273. When
Mapper::mapSimpleMetadata calls Mapper::mapValue, it should not find its
way back to mapMetadataImpl. This guarantees that mapSimpleMetadata is
not involved in any recursion.
Since Mapper::mapValue calls out to arbitrary materializers, we need to
save a bit on the ValueMap to make this assertion effective.
There should be no functionality change here. This co-recursion should
already have been impossible.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265276 91177308-0d34-0410-b5e6-96231b3b80d8
The main change is to delay materializing GlobalValue initializers from
Mapper::mapValue until Mapper::~Mapper. This effectively removes all
recursion from mapSimplifiedMetadata, as promised in r265270.
mapSimplifiedMetadata calls mapValue for ConstantAsMetadata nodes to
find the mapped constant, and now it shouldn't be possible for mapValue
to indirectly re-invoke mapMetadata. I'll add an assertion to that
effect in a follow-up (separated so that the assertion can easily be
reverted independently, if it comes to that).
This a step toward a broader goal: converting Mapper::mapMetadataImpl
from a recursive to an iterative algorithm.
When a BlockAddress points at a BasicBlock inside an unmaterialized
function body, we need to delay it until the function body is
materialized in Mapper::~Mapper. This commit creates a temporary
BasicBlock and returns a new BlockAddress, then RAUWs the BasicBlock
once it is known. This situation should be extremely rare since a
BlockAddress is usually used from within the function it's referencing
(and BlockAddress itself is rare).
There should be no observable functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265273 91177308-0d34-0410-b5e6-96231b3b80d8
Split out a helper for mapping metadata without operands. This is any
metadata that is not an MDNode, and any MDNode where the answer is known
without looking at operands.
Through some weird twists, this function is co-recursive:
mapSimpleMetadata
=> MapValue
=> materializeInitFor
=> linkFunctionBody
=> RemapInstructions
=> MapMetadata
=> mapSimpleMetadata
I plan to break the recursion in a follow-up.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265270 91177308-0d34-0410-b5e6-96231b3b80d8
Instead of checking live during MapMetadata whether a subprogram is
needed, seed the ValueMap with `nullptr` up-front.
There is a small hypothetical functionality change. Previously, calling
MapMetadataOp on a node whose "scope:" chain led to an unneeded
subprogram would return nullptr. However, if that were ever called,
then the subprogram would be needed; a situation that the IRMover is
supposed to avoid a priori!
Besides cleaning up the code a little, this restores a nice property:
MapMetadataOp returns the same as MapMetadata.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265229 91177308-0d34-0410-b5e6-96231b3b80d8
Support seeding a ValueMap with nullptr for Metadata entries, a
situation I didn't consider in the Metadata/Value split.
I added a ValueMapper::getMappedMD accessor that returns an
Optional<Metadata*> with the mapped (possibly null) metadata. IRMover
needs to use this to avoid modifying the map when it's checking for
unneeded subprograms. I updated a call from bugpoint since I find the
new code clearer.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265228 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: This should make the code more readable, especially all the map declarations.
Reviewers: tejohnson
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D18721
From: Mehdi Amini <mehdi.amini@apple.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265215 91177308-0d34-0410-b5e6-96231b3b80d8
Use a helper function to find all the direct-calls-sites in a function.
Also split the code into a separated file as this will be use by
indirect-call-promotion transformation.
Differential Revision: http://reviews.llvm.org/D18704
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265199 91177308-0d34-0410-b5e6-96231b3b80d8
A catchswitch cannot be preceded by another instruction in the same
basic block (other than a PHI node).
Instead, insert the extract element right after the materialization of
the vectorized value. This isn't optimal but is a reasonable compromise
given the constraints of WinEH.
This fixes PR27163.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265157 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r265096, r265095, and r265094.
Windows build is broken, and the validation does not pass.
From: Mehdi Amini <mehdi.amini@apple.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265102 91177308-0d34-0410-b5e6-96231b3b80d8
