Summary:
Final patch in series to fix inlining between functions with different
nobuiltin attributes/options, which was specifically an issue in LTO.
See discussion on D61634 for background.
The prior patch in this series (D67923) enabled per-Function TLI
construction that identified the nobuiltin attributes.
Here I have allowed inlining to proceed if the callee's nobuiltins are a
subset of the caller's nobuiltins, but not in the reverse case, which
should be conservatively correct. This is controlled by a new option,
-inline-caller-superset-nobuiltin, which is enabled by default.
Reviewers: hfinkel, gchatelet, chandlerc, davidxl
Subscribers: arsenm, jvesely, nhaehnle, mehdi_amini, eraman, hiraditya, haicheng, dexonsmith, kerbowa, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D74162
When InstCombine initially populates the worklist, it already
performs constant folding and DCE. However, as the instructions
are initially visited in program order, this DCE can pick up only
the last instruction of a dead chain, the rest would only get
picked up in the main InstCombine run.
To avoid this, we instead perform the DCE in separate pass over the
collected instructions in reverse order, which will allow us to
pick up full dead instruction chains. We already need to do this
reverse iteration anyway to populate the worklist, so this
shouldn't add extra cost.
This by itself only fixes a small part of the problem though:
The same basic issue also applies during the main InstCombine loop.
We generally always want DCE to occur as early as possible,
because it will allow one-use folds to happen. Address this by also
performing DCE while adding deferred instructions to the main worklist.
This drops the number of tests that perform more than 2 InstCombine
iterations from ~80 to ~40. There's some spurious test changes due
to operand order / icmp toggling.
Differential Revision: https://reviews.llvm.org/D75008
Summary:
Future patches will make use of TTI to perform cost-model-driven `SCEVExpander::isHighCostExpansionHelper()`
This is a fully NFC patch to make things reviewable.
Reviewers: reames, mkazantsev, wmi, sanjoy
Reviewed By: mkazantsev
Subscribers: hiraditya, zzheng, javed.absar, dmgreen, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D73704
This patch adds bindings to C and Go for
addCoroutinePassesToExtensionPoints, which is used to add coroutine
passes to the correct locations in PassManagerBuilder.
Differential Revision: https://reviews.llvm.org/D51642
This changes the SimplifyLibCalls utility to accept an IRBuilderBase,
which allows us to pass through the IRBuilder used by InstCombine.
This will ensure that new instructions get added to the worklist.
The annotated test-case drops from 4 to 2 InstCombine iterations thanks
to this.
To achieve this, I'm adding an IRBuilderBase::OperandBundlesGuard,
which is basically the same as the existing InsertPointGuard and
FastMathFlagsGuard, but for operand bundles. Also add a
setDefaultOperandBundles() method so these can be set outside the
constructor.
Differential Revision: https://reviews.llvm.org/D74792
Summary:
As mentioned in D71974, it is useful for must-be-executed-context to explore CFG backwardly.
This patch is ported from parts of D64975. We use a dominator tree to find the previous context if
a dominator tree is available.
Reviewers: jdoerfert, hfinkel, baziotis, sstefan1
Reviewed By: jdoerfert
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D74817
If we propagate function pointers across function boundaries we can
create new call edges. These need to be represented in the CG if we run
as a CGSCC pass. In the new pass manager that is currently not handled
by the CallGraphUpdater so we need to prevent the situation for now.
If a function pointer is casted into a different type the resulting
expression can be a constant. If so, it can be used multiple times which
cannot be handled by the AbstractCallSite constructor alone. Instead, we
follow the cast expression uses now explicitly during the call site
traversal.
Make sure we don't skip the Deferred.remove() call if the
instruction is not in the worklist. Both of those are separate.
We don't have any cases where deferred instructions get removed
right now, but may cause problems in the future.
Summary:
Depends on https://reviews.llvm.org/D71900.
The fourth in a series of patches that ports the LLVM coroutines passes
to the new pass manager infrastructure. This patch implements
'coro-cleanup'.
No existing regression tests check the behavior of coro-cleanup on its
own, so this patch adds one. (A test named 'coro-cleanup.ll' exists, but
it relies on the entire coroutines pipeline being run. It's updated to
test the new pass manager in the 5th patch of this series.)
Reviewers: GorNishanov, lewissbaker, chandlerc, junparser, deadalnix, wenlei
Reviewed By: wenlei
Subscribers: wenlei, EricWF, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D71901
Summary:
Depends on https://reviews.llvm.org/D71899.
The third in a series of patches that ports the LLVM coroutines passes
to the new pass manager infrastructure. This patch implements 'coro-elide'.
The new pass manager infrastructure does not implicitly repeat CGSCC
pass pipelines when a function is devirtualized, and so the tests
for the new pass manager that rely on that behavior now explicitly
specify `repeat<2>`.
Reviewers: GorNishanov, lewissbaker, chandlerc, jdoerfert, junparser, deadalnix, wenlei
Reviewed By: wenlei
Subscribers: wenlei, EricWF, Prazek, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D71900
Summary:
This patch has four dependencies:
1. The first in this series of patches that implement coroutine passes in the
new pass manager: https://reviews.llvm.org/D71898.
2. A patch that introduces an API for CGSCC passes to add new reference
edges to a `LazyCallGraph`, `updateCGAndAnalysisManagerForCGSCCPass`:
https://reviews.llvm.org/D72025.
3. A patch that introduces a `CallGraphUpdater` helper class that is
capable of mutating internal `LazyCallGraph` state in order to insert
new function nodes into a specific SCC: https://reviews.llvm.org/D70927.
4. And finally, a small edge case fix for updating `LazyCallGraph` that
patch 3 above happens to run into: https://reviews.llvm.org/D72226.
This is the second in a series of patches that ports the LLVM coroutines
passes to the new pass manager infrastructure. This patch implements
'coro-split'.
Some notes:
* Using the new CGSCC pass manager resulted in IR being printed in the
reverse order in some tests. To prevent FileCheck checks from failing due
to these reversed orders, this patch splits up test files that test
multiple different coroutine functions: specifically
coro-alloc-with-param.ll, coro-split-eh.ll, and coro-eh-aware-edge-split.ll.
* CoroSplit.cpp contained 2 overloads of `splitCoroutine`, one of which
dispatched to the other based on the coroutine ABI being used (C++20
switch-based versus Swift returned-continuation-based). I found this
confusing, especially with the additional branching based on `CallGraph`
vs. `LazyCallGraph`, so I removed the ABI-checking overload of
`splitCoroutine`.
Reviewers: GorNishanov, lewissbaker, chandlerc, jdoerfert, junparser, deadalnix, wenlei
Reviewed By: wenlei
Subscribers: wenlei, qcolombet, EricWF, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D71899
Summary:
The first in a series of patches that ports the LLVM coroutines passes
to the new pass manager infrastructure. This patch implements
'coro-early'.
NB: All coroutines passes begin by checking that coroutine intrinsics are
declared within the LLVM IR module they're operating on. To do so, they call
`coro::declaresIntrinsics`. The next 3 patches in this series, which add new
pass manager implementations of the 'coro-split', 'coro-elide', and
'coro-cleanup' passes, use a similar pattern as the one used here: a static
function is shared across both old and new passes to detect if relevant
coroutine intrinsics are delcared. To make this pattern easier to read, this
patch adds `const` keywords to the parameters of `coro::declaresIntrinsics`.
Reviewers: GorNishanov, lewissbaker, junparser, chandlerc, deadalnix, wenlei
Reviewed By: wenlei
Subscribers: ychen, wenlei, EricWF, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D71898
In addition to a single bit per memory locations, e.g., globals and
arguments, we now collect more information about the actual accesses,
e.g., what instruction caused it, was it a read/write/read+write, and
what the underlying base pointer was. Follow up patches will make
explicit use of this.
Reviewed By: uenoku
Differential Revision: https://reviews.llvm.org/D73527
In addition to memory behavior attributes (readonly/writeonly) we now
derive memory location attributes (argmemonly/inaccessiblememonly/...).
The former is part of AAMemoryBehavior and the latter part of
AAMemoryLocation. While they are similar in nature it got messy when
they were put in a single AA. Location attributes for arguments and
floating values will follow later.
Note that both memory attributes kinds can derive readnone. If there are
no accesses AAMemoryBehavior will derive readnone. If there are accesses
but only to stack (=local) locations AAMemoryLocation will derive
readnone.
Reviewed By: uenoku
Differential Revision: https://reviews.llvm.org/D73426
replaceDbgDeclare is used to update the descriptions of stack variables
when they are moved (e.g. by ASan or SafeStack). A side effect of
replaceDbgDeclare is that it moves dbg.declares around in the
instruction stream (typically by hoisting them into the entry block).
This behavior was introduced in llvm/r227544 to fix an assertion failure
(llvm.org/PR22386), but no longer appears to be necessary.
Hoisting a dbg.declare generally does not create problems. Usually,
dbg.declare either describes an argument or an alloca in the entry
block, and backends have special handling to emit locations for these.
In optimized builds, LowerDbgDeclare places dbg.values in the right
spots regardless of where the dbg.declare is. And no one uses
replaceDbgDeclare to handle things like VLAs.
However, there doesn't seem to be a positive case for moving
dbg.declares around anymore, and this reordering can get in the way of
understanding other bugs. I propose getting rid of it.
Testing: stage2 RelWithDebInfo sanitized build, check-llvm
rdar://59397340
Differential Revision: https://reviews.llvm.org/D74517
This reverts commit 61b35e4111160fe834a00c33d040e01150b576ac.
This commit causes a timeout in chromium builds; likely to have a
similar cause to the previous timeout issue caused by this commit (see
6ded69f294a9 for more details). It is possible that there is no way to
fix this bug that will not cause this issue; further investigations as
to the efficiency of handling large amounts of debug info will be
necessary.
We used coarse-grained liveness before, thus we looked if the
instruction was executed, but we did not use fine-grained liveness,
hence if the instruction was needed or could be deleted even if the
surrounding ones are live. This patches introduces this level of
liveness checks together with other liveness queries, e.g., for uses.
For more control we enforce that all liveness queries go through the
Attributor.
Test have been adjusted to reflect the changes or augmented to prevent
deletion of the parts we want to check.
Reviewed By: sstefan1
Differential Revision: https://reviews.llvm.org/D73313
This reverts commit 636c93ed11a5f98b5c3ff88241460d61cb7785bb.
The original patch caused build failures on TSan buildbots. Commit 6ded69f294a9
fixes this issue by reducing the rate at which empty debug intrinsics
propagate, reducing the memory footprint and preventing a fatal spike.
The changeXXXAfterManifest functions are better suited to deal with
changes so we should prefer them. These functions also recursively
delete dead instructions which is why we see test changes.
Summary: It attempts to devirtualize a call on alloca through vtable loads.
Reviewers: davidxl
Subscribers: mgorny, Prazek, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D71308
We have several bug reports that could be characterized as "reducing scalarization",
and this topic was also raised on llvm-dev recently:
http://lists.llvm.org/pipermail/llvm-dev/2020-January/138157.html
...so I'm proposing that we deal with these patterns in a new, lightweight IR vector
pass that runs before/after other vectorization passes.
There are 4 alternate options that I can think of to deal with this kind of problem
(and we've seen various attempts at all of these), but they all have flaws:
InstCombine - can't happen without TTI, but we don't want target-specific
folds there.
SDAG - too late to assist other vectorization passes; TLI is not equipped
for these kind of cost queries; limited to a single basic block.
CGP - too late to assist other vectorization passes; would need to re-implement
basic cleanups like CSE/instcombine.
SLP - doesn't fit with existing transforms; limited to a single basic block.
This initial patch/transform is based on existing code in AggressiveInstCombine:
we walk backwards through the function looking for a pattern match. But we diverge
from that cost-independent IR canonicalization pass by using TTI to decide if the
vector alternative is profitable.
We probably have at least 10 similar bug reports/patterns (binops, constants,
inserts, cheap shuffles, etc) that would fit in this pass as follow-up enhancements.
It's possible that we could iterate on a worklist to fix-point like InstCombine does,
but it's safer to start with a most basic case and evolve from there, so I didn't
try to do anything fancy with this initial implementation.
Differential Revision: https://reviews.llvm.org/D73480
In addition to the module pass, this patch introduces a CGSCC pass that
runs the Attributor on a strongly connected component of the call graph
(both old and new PM). The Attributor was always design to be used on a
subset of functions which makes this patch mostly mechanical.
The one change is that we give up `norecurse` deduction in the module
pass in favor of doing it during the CGSCC pass. This makes the
interfaces simpler but can be revisited if needed.
Reviewed By: hfinkel
Differential Revision: https://reviews.llvm.org/D70767
The OpenMPOpt pass is a CGSCC pass in which OpenMP specific
optimizations can reside.
The OpenMPOpt pass uses the OpenMPKinds.def file to identify runtime
calls and their uses. This allows targeted transformations and eases
their implementation.
This initial patch deduplicates `__kmpc_global_thread_num` and
`omp_get_thread_num` calls. We can also identify arguments that are
equivalent to such a call result and use it instead. Later we can
determine "gtid" arguments based on the use in kernel functions etc.
Reviewed By: JonChesterfield
Differential Revision: https://reviews.llvm.org/D69930
The CallGraphUpdater is a helper that simplifies the process of updating
the call graph, both old and new style, while running an CGSCC pass.
The uses are contained in different commits, e.g. D70767.
More functionality is added as we need it.
Reviewed By: modocache, hfinkel
Differential Revision: https://reviews.llvm.org/D70927
Bionic has had `__strlen_chk` for a while. Optimizing that into a
constant is quite profitable, when possible.
Differential Revision: https://reviews.llvm.org/D74079
Summary:
Tune the profile threshold flag value for instrumentation PGO based on internal
benchmarks.
Also, add flags to allow profile guided size optimizations for non-cold code
to be enabled separately for instrumentation and sample PGSO.
Neither changes the default behavior (yet) as it's disabled for non-cold code.
Reviewers: davidxl
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D72937
This reverts commit 41784bed01543315a1d03141e6ddc023fd914c0b.
Since the original revision ead815924e6ebeaf02c31c37ebf7a560b5fdf67b,
this revision fixes three issues:
- This revision fixes the Windows build. My original patch improperly
copied EH pads on Windows. This patch disregards jump threading
opportunities having to do with EH pads.
- This revision fixes jump threading to a wrong destination.
Specifically, my original patch treated any Constant other than 0 as 1
while evaluating the branch condition. This bug led to treating
constant expressions like:
icmp ugt i8* null, inttoptr (i64 4 to i8*)
to "true". This patch fixes the bug by calling isOneValue.
- This revision fixes the cost calculation of two basic blocks being
threaded through. Note that getJumpThreadDuplicationCost returns
"(unsigned)~0" for those basic blocks that cannot be duplicated. If
we sum of two return values from getJumpThreadDuplicationCost, we
could have an unsigned overflow like:
(unsigned)~0 + 5 = 4
and mistakenly determine that it's safe and profitable to proceed
with the jump threading opportunity. The patch fixes the bug by
checking each return value before summing them up.
[JumpThreading] Thread jumps through two basic blocks
Summary:
This patch teaches JumpThreading.cpp to thread through two basic
blocks like:
bb3:
%var = phi i32* [ null, %bb1 ], [ @a, %bb2 ]
%tobool = icmp eq i32 %cond, 0
br i1 %tobool, label %bb4, label ...
bb4:
%cmp = icmp eq i32* %var, null
br i1 %cmp, label bb5, label bb6
by duplicating basic blocks like bb3 above. Once we duplicate bb3 as
bb3.dup and redirect edge bb2->bb3 to bb2->bb3.dup, we have:
bb3:
%var = phi i32* [ @a, %bb2 ]
%tobool = icmp eq i32 %cond, 0
br i1 %tobool, label %bb4, label ...
bb3.dup:
%var = phi i32* [ null, %bb1 ]
%tobool = icmp eq i32 %cond, 0
br i1 %tobool, label %bb4, label ...
bb4:
%cmp = icmp eq i32* %var, null
br i1 %cmp, label bb5, label bb6
Then the existing code in JumpThreading.cpp can thread edge
bb3.dup->bb4 through bb4 and eventually create bb3.dup->bb5.
Reviewers: wmi
Subscribers: hiraditya, jfb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D70247
Adds the global (cl::opt) GVNOption enable-load-in-loop-pre in order
to control whether the optimization will be performed if the load
is part of a loop.
Patch by Hendrik Greving!
Differential Revision: https://reviews.llvm.org/D73804
Summary:
Method appendLoopsToWorklist is duplicate in LoopUnroll and in the
LoopPassManager as an internal method. Make it an utility.
Reviewers: dmgreen, chandlerc, fedor.sergeev, yamauchi
Subscribers: mehdi_amini, hiraditya, zzheng, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D73569
This renames Worklist.AddDeferred() to Worklist.add() and
Worklist.Add() to Worklist.push(). The intention here is that
Worklist.add() should be the go-to method for explicit worklist
management, while the raw Worklist.push() is mostly for
InstCombine internals. I will then migrate uses of Worklist.push()
to Worklist.add() in followup changes.
As suggested by spatel on D73411 I'm also changing the remaining
method names to lowercase first character, in line with current
coding standards.
Differential Revision: https://reviews.llvm.org/D73745
Duplicating instructions can lead to code size increases but using
a threshold of 3 is good for reducing code size.
Differential Revision: https://reviews.llvm.org/D72916
If we know that all call sites have been processed we can derive an
early fixpoint. The use in this patch is likely not to trigger right now
but a follow up patch will make use of it.
Reviewed By: uenoku, baziotis
Differential Revision: https://reviews.llvm.org/D72016
Fix attempt
this is part of the implementation of http://lists.llvm.org/pipermail/llvm-dev/2019-December/137632.html
this patch gives the basis of building an assume to preserve all information from an instruction and add support for building an assume that preserve the information from a call.
Summary:
this is part of the implementation of http://lists.llvm.org/pipermail/llvm-dev/2019-December/137632.html
this patch gives the basis of building an assume to preserve all information from an instruction and add support for building an assume that preserve the information from a call.
Reviewers: jdoerfert
Reviewed By: jdoerfert
Subscribers: mgrang, fhahn, mgorny, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D72475
Summary:
this is part of the implementation of http://lists.llvm.org/pipermail/llvm-dev/2019-December/137632.html
this patch gives the basis of building an assume to preserve all information from an instruction and add support for building an assume that preserve the information from a call.
Reviewers: jdoerfert
Reviewed By: jdoerfert
Subscribers: mgrang, fhahn, mgorny, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D72475
Summary:
this is part of the implementation of http://lists.llvm.org/pipermail/llvm-dev/2019-December/137632.html
this patch gives the basis of building an assume to preserve all information from an instruction and add support for building an assume that preserve the information from a call.
Reviewers: jdoerfert
Reviewed By: jdoerfert
Subscribers: mgrang, fhahn, mgorny, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D72475
Summary:
this is part of the implementation of http://lists.llvm.org/pipermail/llvm-dev/2019-December/137632.html
this patch gives the basis of building an assume to preserve all information from an instruction and add support for building an assume that preserve the information from a call.
Reviewers: jdoerfert
Reviewed By: jdoerfert
Subscribers: mgrang, fhahn, mgorny, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D72475
Some code gen passes use MBFIWrapper to keep track of the frequency of new
blocks. This was not taken into account and could lead to incorrect frequencies
as MBFI silently returns zero frequency for unknown/new blocks.
Add a variant for MBFIWrapper in the PGSO query interface.
Depends on D73494.
InstCombine operates on the basic premise that the operands of the
currently processed instruction have already been simplified. It
achieves this by pushing instructions to the worklist in reverse
program order, so that instructions are popped off in program order.
The worklist management in the main combining loop also makes sure
to uphold this invariant.
However, the same is not true for all the code that is performing
manual worklist management. The largest problem (addressed in this
patch) are instructions inserted by InstCombine's IRBuilder. These
will be pushed onto the worklist in order of insertion (generally
matching program order), which means that a) the users of the
original instruction will be visited first, as they are pushed later
in the main loop and b) the newly inserted instructions will be
visited in reverse program order.
This causes a number of problems: First, folds operate on instructions
that have not had their operands simplified, which may result in
optimizations being missed (ran into this in
https://reviews.llvm.org/D72048#1800424, which was the original
motivation for this patch). Additionally, this increases the amount
of folds InstCombine has to perform, both within one iteration, and
by increasing the number of total iterations.
This patch addresses the issue by adding a Worklist.AddDeferred()
method, which is used for instructions inserted by IRBuilder. These
will only be added to the real worklist after the combine finished,
and in reverse order, so they will end up processed in program order.
I should note that the same should also be done to nearly all other
uses of Worklist.Add(), but I'm starting with just this occurrence,
which has by far the largest test fallout.
Most of the test changes are due to
https://bugs.llvm.org/show_bug.cgi?id=44521 or other cases where
we don't canonicalize something. These are neutral. One regression
has been addressed in D73575 and D73647. The remaining regression
in an shl+sdiv fold can't really be fixed without dropping another
transform, but does not seem particularly problematic in the first
place.
Differential Revision: https://reviews.llvm.org/D73411
A pointer is privatizeable if it can be replaced by a new, private one.
Privatizing pointer reduces the use count, interaction between unrelated
code parts. This is a first step towards replacing argument promotion.
While we can already handle recursion (unlike argument promotion!) we
are restricted to stack allocations for now because we do not analyze
the uses in the callee.
Reviewed By: uenoku
Differential Revision: https://reviews.llvm.org/D68852
The helpers AAReturnedFromReturnedValues and
AACallSiteReturnedFromReturned are useful not only to avoid code
duplication but also to avoid recomputation of results. If we have N
call sites we should not recompute the function return information N
times but once. These are mostly straightforward usages with some minor
improvements on the helpers and addition of a new one
(IRPosition::getAssociatedType) that knows about function return types.
This commit fixes PR39321.
GlobalExtensions is not guaranteed to be destroyed when optimizer plugins are unloaded. If it is indeed destroyed after a plugin is dlclose-d, the destructor of the corresponding ExtensionFn is not mapped anymore, causing a call to unmapped memory during destruction.
This commit guarantees that extensions coming from external plugins are removed from GlobalExtensions when the plugin is unloaded if GlobalExtensions has not been destroyed yet.
Differential Revision: https://reviews.llvm.org/D71959
proven safe.
Summary:
Currently LoopFusion give up when the second loop nest preheader is
not empty. For example:
for (int i = 0; i < 100; ++i) {}
x+=1;
for (int i = 0; i < 100; ++i) {}
The above example should be safe to fuse.
This PR moves instructions in FC1 preheader (e.g. x+=1; ) to
FC0 preheader, which then LoopFusion is able to fuse them.
Reviewer: kbarton, Meinersbur, jdoerfert, dmgreen, fhahn, hfinkel,
bmahjour, etiotto
Reviewed By: jdoerfert
Subscribers: hiraditya, llvm-commits
Tag: LLVM
Differential Revision: https://reviews.llvm.org/D71821
There was a TODO in AAValueConstantRangeArgument to reuse
AAArgumentFromCallSiteArguments. We now do this by allowing new States
to be build from the bestState.
During extraction, stale llvm.assume handles may be retained in the
original function. The setup is:
1) CodeExtractor unregisters assumptions in the blocks that are to be
extracted.
2) Extraction happens. There are now two functions: f1 and f1.extracted.
3) Leftover assumptions in f1 (/not/ removed as they were not in the set of
blocks to be extracted) now have affected-value llvm.assume handles in
f1.extracted.
When assumptions for a value used in f1 are looked up, ValueTracking can assert
as some of the handles are in the wrong function. To fix this, simply erase the
llvm.assume calls in the extracted function.
Alternatives include flushing the assumption cache in the original function, or
walking all values used in the original function to prune stale affected-value
handles. Both seem more expensive.
Testing: check-llvm, LNT run with -mllvm -hot-cold-split enabled
rdar://58460728
Summary:
Currently IsControlFlowEquivalent determine if two blocks are control
flow equivalent by checking if A dominates B and B post dominates A.
There exists blocks that are control flow equivalent even if they don't
satisfy the A dominates B and B post dominates A condition.
For example,
if (cond)
A
if (cond)
B
In the PR, we determine if two blocks are control flow equivalent by
also checking if the two sets of conditions A and B depends on are
equivalent.
Reviewer: jdoerfert, Meinersbur, dmgreen, etiotto, bmahjour, fhahn,
hfinkel, kbarton
Reviewed By: fhahn
Subscribers: hiraditya, llvm-commits
Tag: LLVM
Differential Revision: https://reviews.llvm.org/D71578
from DenseMap to MapVector
The iteration order of LoopVectorizationLegality::Reductions matters for the
final code generation, so we better use MapVector instead of DenseMap for it
to remove the nondeterminacy. reduction-order.ll in the patch is an example
reduced from the case we saw. In the output of opt command, the order of the
select instructions in the vector.body block keeps changing from run to run
currently.
Differential Revision: https://reviews.llvm.org/D73490
This restores 59733525d37cf9ad88b5021b33ecdbaf2e18911c (D71913), along
with bot fix 19c76989bb505c3117730c47df85fd3800ea2767.
The bot failure should be fixed by D73418, committed as
af954e441a5170a75687699d91d85e0692929d43.
I also added a fix for non-x86 bot failures by requiring x86 in new test
lld/test/ELF/lto/devirt_vcall_vis_public.ll.
Summary:
LoopUnroll can reuse the RemapInstruction() in ValueMapper, or
remapInstructionsInBlocks() in CloneFunction, depending on the needs.
There is no need to have its own version in LoopUnroll.
By calling RemapInstruction() without TypeMapper or Materializer and
with Flags (RF_NoModuleLevelChanges | RF_IgnoreMissingLocals), it does
the same as remapInstruction(). remapInstructionsInBlocks() calls
RemapInstruction() exactly as described.
Looking at the history, I cannot find any obvious reason to have its own
version.
Reviewer: dmgreen, jdoerfert, Meinersbur, kbarton, bmahjour, etiotto,
foad, aprantl
Reviewed By: jdoerfert
Subscribers: hiraditya, zzheng, llvm-commits, prithayan, anhtuyen
Tag: LLVM
Differential Revision: https://reviews.llvm.org/D73277
It can happen that we have instructions in the ToBeDeletedInsts set
which are deleted earlier already. To avoid dangling pointers we use
weak tracking handles.
Create a utility wrapper for the RecursivelyDeleteTriviallyDeadInstructions utility
method, which sets to nullptr the instructions that are not trivially
dead. Use the new method in LoopStrengthReduce.
Alternative: add a bool to the same method; this option adds a marginal
amount of overhead to the other callers, and the method needs to be
updated to return a bool status when it removes/doesn't remove
instructions.
Summary:
Third part in series to support Safe Whole Program Devirtualization
Enablement, see RFC here:
http://lists.llvm.org/pipermail/llvm-dev/2019-December/137543.html
This patch adds type test metadata under -fwhole-program-vtables,
even for classes without hidden visibility. It then changes WPD to skip
devirtualization for a virtual function call when any of the compatible
vtables has public vcall visibility.
Additionally, internal LLVM options as well as lld and gold-plugin
options are added which enable upgrading all public vcall visibility
to linkage unit (hidden) visibility during LTO. This enables the more
aggressive WPD to kick in based on LTO time knowledge of the visibility
guarantees.
Support was added to all flavors of LTO WPD (regular, hybrid and
index-only), and to both the new and old LTO APIs.
Unfortunately it was not simple to split the first and second parts of
this part of the change (the unconditional emission of type tests and
the upgrading of the vcall visiblity) as I needed a way to upgrade the
public visibility on legacy WPD llvm assembly tests that don't include
linkage unit vcall visibility specifiers, to avoid a lot of test churn.
I also added a mechanism to LowerTypeTests that allows dropping type
test assume sequences we now aggressively insert when we invoke
distributed ThinLTO backends with null indexes, which is used in testing
mode, and which doesn't invoke the normal ThinLTO backend pipeline.
Depends on D71907 and D71911.
Reviewers: pcc, evgeny777, steven_wu, espindola
Subscribers: emaste, Prazek, inglorion, arichardson, hiraditya, MaskRay, dexonsmith, dang, davidxl, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D71913
The utility method RecursivelyDeleteTriviallyDeadInstructions receives
as input a vector of Instructions, where all inputs are valid
instructions. This same vector is used as a scratch storage (per the
header comment) to recursively delete instructions. If an instruction is
added as an operand of multiple other instructions, it may be added twice,
then deleted once, then the second reference in the vector is invalid.
Switch to using a Vector<WeakTrackingVH>.
This change facilitates a clean-up in LoopStrengthReduction.
Summary: Vectorized loop processes VFxUF number of elements in one iteration thus total number of iterations decreases proportionally. In addition epilog loop may not have more than VFxUF - 1 iterations. This patch updates profile information accordingly.
Reviewers: hsaito, Ayal, fhahn, reames, silvas, dcaballe, SjoerdMeijer, mkuper, DaniilSuchkov
Reviewed By: Ayal, DaniilSuchkov
Subscribers: fedor.sergeev, hiraditya, rkruppe, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67905
This moves `rewriteLoopExitValues()` from IndVarSimplify to LoopUtils thus
making it a generic loop utility function. This allows to rewrite loop exit
values by just calling this function without running the whole IndVarSimplify
pass.
We use this in D72714 to rematerialise the iteration count in exit blocks, so
that we can clean-up loop update expressions inside the hardware-loops later.
Differential Revision: https://reviews.llvm.org/D72602
This is an alternative to the continous mode that was implemented in
D68351. This mode relies on padding and the ability to mmap a file over
the existing mapping which is generally only available on POSIX systems
and isn't suitable for other platforms.
This change instead introduces the ability to relocate counters at
runtime using a level of indirection. On every counter access, we add a
bias to the counter address. This bias is stored in a symbol that's
provided by the profile runtime and is initially set to zero, meaning no
relocation. The runtime can mmap the profile into memory at abitrary
location, and set bias to the offset between the original and the new
counter location, at which point every subsequent counter access will be
to the new location, which allows updating profile directly akin to the
continous mode.
The advantage of this implementation is that doesn't require any special
OS support. The disadvantage is the extra overhead due to additional
instructions required for each counter access (overhead both in terms of
binary size and performance) plus duplication of counters (i.e. one copy
in the binary itself and another copy that's mmapped).
Differential Revision: https://reviews.llvm.org/D69740
This include file was created in October and has a "using namespace llvm". This seems to get exposed to other include files and finally onto cpp files. While this somewhat okay for llvm itself, its bad for other projects that use llvm as a library and includes a header file that picks this up. This was found by ISPC which has some class names at gloal scope with the same names as LLVM.
It looks like RISCV accidentally became dependent on this. I fixed it by reordering some includes in the RISCV code, but maybe we want to change the TableGenEmitter to put "namespace llvm {" in the generated file instead? But we probably want to do the simplest thing first so we can merge it to 10.0.
Differential Revision: https://reviews.llvm.org/D72895
There are a few global (cl::opt) controls that enable optional
behavior in GVN. Introduce GVNOptions that provide corresponding
per-pass instance controls.
That will allow to use GVN multiple times in pipeline each time
with different settings.
Reviewers: asbirlea, rnk, reames, skatkov, fhahn
Reviewed By: fhahn
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D72732
The assume intrinsic is intentionally marked as may reading/writing
memory, to avoid passes moving them around. When flattening the CFG
for predicated blocks, we have to drop the assume calls, as they
are control-flow dependent.
There are some cases where we can do better (when control flow is
preserved), but that is follow-up work.
Fixes PR43620.
Reviewers: hsaito, rengolin, dcaballe, Ayal
Reviewed By: Ayal
Differential Revision: https://reviews.llvm.org/D68814
Summary:
This change implements the expansion in two parts:
- Add a utility function emitAMDGPUPrintfCall() in LLVM.
- Invoke the above function from Clang CodeGen, when processing a HIP
program for the AMDGPU target.
The printf expansion has undefined behaviour if the format string is
not a compile-time constant. As a sufficient condition, the HIP
ToolChain now emits -Werror=format-nonliteral.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D71365
Summary:
This patch introduces `AAValueConstantRange`, which answers a possible range for integer value in a specific program point.
One of the motivations is propagating existing `range` metadata. (I think we need to change the situation that `range` metadata cannot be put to Argument).
The state is a tuple of `ConstantRange` and it is initialized to (known, assumed) = ([-∞, +∞], empty).
Currently, AAValueConstantRange is created in `getAssumedConstant` method when `AAValueSimplify` returns `nullptr`(worst state).
Supported
- BinaryOperator(add, sub, ...)
- CmpInst(icmp eq, ...)
- !range metadata
`AAValueConstantRange` is not intended to extend to polyhedral range value analysis.
Reviewers: jdoerfert, sstefan1
Reviewed By: jdoerfert
Subscribers: phosek, davezarzycki, baziotis, hiraditya, javed.absar, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D71620
This ports the MergeFunctions pass to the NewPM. This was rather
straightforward, as no analyses are used.
Additionally MergeFunctions needs to be conditionally enabled in
the PassBuilder, but I left that part out of this patch.
Differential Revision: https://reviews.llvm.org/D72537
pass.
Summary: This patch changes LoopUnrollAndJamPass to a function pass, and
keeps the loops traversal order same as defined in
FunctionToLoopPassAdaptor LoopPassManager.h.
The next patch will change the loop traversal to outer to inner order,
so more loops can be transform.
Discussion in llvm-dev mailing list:
https://groups.google.com/forum/#!topic/llvm-dev/LF4rUjkVI2g
Reviewer: dmgreen, jdoerfert, Meinersbur, kbarton, bmahjour, etiotto
Reviewed By: dmgreen
Subscribers: hiraditya, zzheng, llvm-commits
Tag: LLVM
Differential Revision: https://reviews.llvm.org/D72230
When we replace instructions with unreachable we delete instructions. We
now avoid dangling pointers to those deleted instructions in the
`ToBeChangedToUnreachableInsts` set. Other modification collections
might need to be updated in the future as well.
SCEVExpander modifies the underlying function so it is more suitable in
Transforms/Utils, rather than Analysis. This allows using other
transform utils in SCEVExpander.
Reviewers: sanjoy.google, efriedma, reames
Reviewed By: sanjoy.google
Differential Revision: https://reviews.llvm.org/D71537
A series of patches beginning with https://reviews.llvm.org/D71898
propose to add an implementation of the coroutine passes to the new pass
manager. As part of these changes, the coroutine passes that implement
the legacy pass manager interface are renamed, to `<PassName>Legacy`.
This mirrors similar changes that have been made to many other passes in
LLVM as they've been transitioned to support both old and new pass
managers.
This commit splits out the renaming portion of that patch and commits it
in advance as an NFC (no functional change intended) commit. It renames:
* `CoroEarly` => `CoroEarlyLegacy`
* `CoroSplit` => `CoroSplitLegacy`
* `CoroElide` => `CoroElideLegacy`
* `CoroCleanup` => `CoroCleanupLegacy`
This patch introduces `AAValueConstantRange`, which answers a possible range for integer value in a specific program point.
One of the motivations is propagating existing `range` metadata. (I think we need to change the situation that `range` metadata cannot be put to Argument).
The state is a tuple of `ConstantRange` and it is initialized to (known, assumed) = ([-∞, +∞], empty).
Currently, AAValueConstantRange is created when AAValueSimplify cannot
simplify the value.
Supported
- BinaryOperator(add, sub, ...)
- CmpInst(icmp eq, ...)
- !range metadata
`AAValueConstantRange` is not intended to extend to polyhedral range value analysis.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D71620
As part of the Attributor manifest we want to change the signature of
functions. This patch introduces a fairly generic interface to do so.
As a first, very simple, use case, we remove unused arguments. A second
use case, pointer privatization, will be committed with this patch as
well.
A lot of the code and ideas are taken from argument promotion and we
run all argument promotion tests through this framework as well.
Reviewed By: uenoku
Differential Revision: https://reviews.llvm.org/D68765
This is the second step after D67871 to make use of abstract call sites.
In this patch the argument we associate with a abstract call site
argument can be the one in the callback callee instead of the one in the
callback broker.
Caveat: We cannot allow no-alias arguments for problematic callbacks:
As described in [1], adding no-alias (or restrict) to arguments could
break synchronization as the synchronization effect, e.g., a barrier,
does not "alias" with the pointer anymore. This disables no-alias
annotation for potentially problematic arguments until we implement the
fix described in [1].
Reviewed By: uenoku
Differential Revision: https://reviews.llvm.org/D68008
[1] Compiler Optimizations for OpenMP, J. Doerfert and H. Finkel,
International Workshop on OpenMP 2018,
http://compilers.cs.uni-saarland.de/people/doerfert/par_opt18.pdf
Summary: This patch makes `AAValueSimplify` use `changeUsesAfterManifest` in `manifest`. This will invoke simple folding after the manifest.
Reviewers: jdoerfert, sstefan1
Reviewed By: jdoerfert
Subscribers: hiraditya, arphaman, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D71972
A branch is considered UB if it depends on an undefined / uninitialized value.
At this point this handles simple UB branches in the form: `br i1 undef, ...`
We query `AAValueSimplify` to get a value for the branch condition, so the branch
can be more complicated than just: `br i1 undef, ...`.
Patch By: Stefanos Baziotis (@baziotis)
Reviewers: jdoerfert, sstefan1, uenoku
Reviewed By: uenoku
Differential Revision: https://reviews.llvm.org/D71799
Summary: Calling `changeToUnreachable` in `manifest` from different places might cause really unpredictable problems. As other deleting functions are doing, we need to change these instructions after all `manifest`.
Reviewers: jdoerfert, sstefan1
Reviewed By: jdoerfert
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D71910
_Eventually_, this attribute will be assigned to a function if it
contains undefined behavior. As a first small step, I tried to make it
loop through the load instructions in a function (eventually, the plan
is to check if a load instructions causes undefined behavior, because
e.g. dereferences a null pointer - Also eventually, this won't happen in
initialize() but in updateImpl()).
Patch By: Stefanos Baziotis (@baziotis)
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D71435
Summary:
This patch adds instructions to the InstCombine worklist after they are properly inserted. This way we don't get `<badref>`s printed when logging added instructions.
It also adds a check in `Worklist::Add` that ensures that all added instructions have parents.
Simple test case that illustrates the difference when run with `--debug-only=instcombine`:
```
define i32 @test35(i32 %a, i32 %b) {
%1 = or i32 %a, 1135
%2 = or i32 %1, %b
ret i32 %2
}
```
Before this patch:
```
INSTCOMBINE ITERATION #1 on test35
IC: ADDING: 3 instrs to worklist
IC: Visiting: %1 = or i32 %a, 1135
IC: Visiting: %2 = or i32 %1, %b
IC: ADD: %2 = or i32 %a, %b
IC: Old = %3 = or i32 %1, %b
New = <badref> = or i32 %2, 1135
IC: ADD: <badref> = or i32 %2, 1135
...
```
With this patch:
```
INSTCOMBINE ITERATION #1 on test35
IC: ADDING: 3 instrs to worklist
IC: Visiting: %1 = or i32 %a, 1135
IC: Visiting: %2 = or i32 %1, %b
IC: ADD: %2 = or i32 %a, %b
IC: Old = %3 = or i32 %1, %b
New = <badref> = or i32 %2, 1135
IC: ADD: %3 = or i32 %2, 1135
...
```
Reviewers: fhahn, davide, spatel, foad, grosser, nikic
Reviewed By: nikic
Subscribers: nikic, lebedev.ri, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D71093
Summary:
This patch teaches InstCombine to accept a new parameter: maximum number of iterations over functions.
InstCombine tries to simplify instructions by iterating over the whole function until the function stops changing. As a consequence, the last iteration before reaching a fixpoint visits all instructions in the worklist and never performs any rewrites.
Bounding the number of iterations can have 2 benefits:
* In case the users of the pass can make a good guess about the number of required iterations, we can save the time normally spent on the last iteration that doesn't change anything.
* When the wants to use InstCombine as a cleanup pass, it may be enough to run just a few iterations and stop even before reaching a fixpoint. This can be also useful for implementing a lightweight pass pipeline (think `-O1`).
This patch does not change the behavior of opt or Clang -- limiting the number of iterations is entirely opt-in.
Reviewers: fhahn, davide, spatel, foad, nlopes, grosser, lebedev.ri, nikic, xbolva00
Reviewed By: spatel
Subscribers: craig.topper, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D71145
Summary:This PR move instructions from FC0.Latch bottom up to the
beginning of FC1.Latch as long as they are proven safe.
To illustrate why this is beneficial, let's consider the following
example:
Before Fusion:
header1:
br header2
header2:
br header2, latch1
latch1:
br header1, preheader3
preheader3:
br header3
header3:
br header4
header4:
br header4, latch3
latch3:
br header3, exit3
After Fusion (before this PR):
header1:
br header2
header2:
br header2, latch1
latch1:
br header3
header3:
br header4
header4:
br header4, latch3
latch3:
br header1, exit3
Note that preheader3 is removed during fusion before this PR.
Notice that we cannot fuse loop2 with loop4 as there exists block latch1
in between.
This PR move instructions from latch1 to beginning of latch3, and remove
block latch1. LoopFusion is now able to fuse loop nest recursively.
After Fusion (after this PR):
header1:
br header2
header2:
br header3
header3:
br header4
header4:
br header2, latch3
latch3:
br header1, exit3
Reviewer: kbarton, jdoerfert, Meinersbur, dmgreen, fhahn, hfinkel,
bmahjour, etiotto
Reviewed By: kbarton, Meinersbur
Subscribers: hiraditya, llvm-commits
Tag: LLVM
Differential Revision: https://reviews.llvm.org/D71165
Summary:
Add a RemoveRedundantDbgInstrs to BasicBlockUtils with the
goal to remove redundant dbg intrinsics from a basic block.
This can be useful after various transforms, as it might
be simpler to do a filtering of dbg intrinsics after the
transform than during the transform.
One primary use case would be to replace a too aggressive
removal done by MergeBlockIntoPredecessor, seen at loop
rotate (not done in this patch).
The elimination algorithm currently focuses on dbg.value
intrinsics and is doing two iterations over the BB.
First we iterate backward starting at the last instruction
in the BB. Whenever a consecutive sequence of dbg.value
instructions are found we keep the last dbg.value for
each variable found (variable fragments are identified
using the {DILocalVariable, FragmentInfo, inlinedAt}
triple as given by the DebugVariable helper class).
Next we iterate forward starting at the first instruction
in the BB. Whenever we find a dbg.value describing a
DebugVariable (identified by {DILocalVariable, inlinedAt})
we save the {DIValue, DIExpression} that describes that
variables value. But if the variable already was mapped
to the same {DIValue, DIExpression} pair we instead drop
the second dbg.value.
To ease the process of making lit tests for this utility a
new pass is introduced called RedundantDbgInstElimination.
It can be executed by opt using -redundant-dbg-inst-elim.
Reviewers: aprantl, jmorse, vsk
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D71478
When we reason about the pointer argument that is byval we actually
reason about a local copy of the value passed at the call site. This was
not the case before and we wrongly introduced attributes based on the
surrounding function.
AAMemoryBehaviorArgument, AAMemoryBehaviorCallSiteArgument and
AANoCaptureCallSiteArgument are made aware of byval now. The code
to skip "subsuming positions" for reasoning follows a common pattern and
we should refactor it. A TODO was added.
Discovered by @efriedma as part of D69748.
This is the first patch adding an initial set of matrix intrinsics and a
corresponding lowering pass. This has been discussed on llvm-dev:
http://lists.llvm.org/pipermail/llvm-dev/2019-October/136240.html
The first patch introduces four new intrinsics (transpose, multiply,
columnwise load and store) and a LowerMatrixIntrinsics pass, that
lowers those intrinsics to vector operations.
Matrixes are embedded in a 'flat' vector (e.g. a 4 x 4 float matrix
embedded in a <16 x float> vector) and the intrinsics take the dimension
information as parameters. Those parameters need to be ConstantInt.
For the memory layout, we initially assume column-major, but in the RFC
we also described how to extend the intrinsics to support row-major as
well.
For the initial lowering, we split the input of the intrinsics into a
set of column vectors, transform those column vectors and concatenate
the result columns to a flat result vector.
This allows us to lower the intrinsics without any shape propagation, as
mentioned in the RFC. In follow-up patches, we plan to submit the
following improvements:
* Shape propagation to eliminate the embedding/splitting for each
intrinsic.
* Fused & tiled lowering of multiply and other operations.
* Optimization remarks highlighting matrix expressions and costs.
* Generate loops for operations on large matrixes.
* More general block processing for operation on large vectors,
exploiting shape information.
We would like to add dedicated transpose, columnwise load and store
intrinsics, even though they are not strictly necessary. For example, we
could instead emit a large shufflevector instruction instead of the
transpose. But we expect that to
(1) become unwieldy for larger matrixes (even for 16x16 matrixes,
the resulting shufflevector masks would be huge),
(2) risk instcombine making small changes, causing us to fail to
detect the transpose, preventing better lowerings
For the load/store, we are additionally planning on exploiting the
intrinsics for better alias analysis.
Reviewers: anemet, Gerolf, reames, hfinkel, andrew.w.kaylor, efriedma, rengolin
Reviewed By: anemet
Differential Revision: https://reviews.llvm.org/D70456
Soon Intrinsic::ID will be a plain integer, so this overload will not be
possible.
Rename both overloads to ensure that downstream targets observe this as
a build failure instead of a runtime failure.
Split off from D71320
Reviewers: efriedma
Differential Revision: https://reviews.llvm.org/D71381
basic blocks
Originally applied in 72ce759928e6dfee6a9efa310b966c19722352ba.
Fixed a build failure caused by incorrect use of cast instead of
dyn_cast.
This reverts commit 8b0780f795eb58fca0a2456e308adaaa1a0b5013.
Summary:
This is one more prep step necessary before the code gen pass instrumentation
code could go in.
Reviewers: davidxl
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D70988
When basic blocks are killed, either due to being empty or to being an if.then
or if.else block whose complement contains identical instructions, some of the
debug intrinsics in that block are lost. This patch sinks those intrinsics
into the single successor block, setting them Undef if necessary to
prevent debug info from falling out-of-date.
Differential Revision: https://reviews.llvm.org/D70318
Summary:
In case of a need to distinguish different query sites for gradual commit or
debugging of PGSO. NFC.
Reviewers: davidxl
Subscribers: hiraditya, zzheng, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D70510
Summary:
This patch introduces the deduction based on load/store instructions whose pointer operand is a non-inbounds GEP instruction.
For example if we have,
```
void f(int *u){
u[0] = 0;
u[1] = 1;
u[2] = 2;
}
```
then u must be dereferenceable(12).
This patch is inspired by D64258
Reviewers: jdoerfert, spatel, hfinkel, RKSimon, sstefan1, xbolva00, dtemirbulatov
Reviewed By: jdoerfert
Subscribers: jfb, lebedev.ri, xbolva00, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D70714
moved before another instruction.
Summary:Added an API to check if an instruction can be safely moved
before another instruction. In future PRs, we will like to add support
of moving instructions between blocks that are not control flow
equivalent, and add other APIs to enhance usability, e.g. moving basic
blocks, moving list of instructions...
Loop Fusion will be its first user. When there is intervening code in
between two loops, fusion is currently unable to fuse them. Loop Fusion
can use this utility to check if the intervening code can be safely
moved before or after the two loops, and move them, then it can
successfully fuse them.
Reviewer:kbarton,jdoerfert,Meinersbur,bmahjour,etiotto
Reviewed By:bmahjour
Subscribers:mgorny,hiraditya,llvm-commits
Tag:LLVM
Differential Revision:https://reviews.llvm.org/D70049
Summary: Working towards Johannes's suggestion for fixme, in Attributor's Noalias attribute deduction.
(ii) Check whether the value is captured in the scope using AANoCapture.
FIXME: This is conservative though, it is better to look at CFG and
// check only uses possibly executed before this call site.
A Reachability abstract attribute answers the question "does execution at point A potentially reach point B". If this question is answered with false for all other uses of the value that might be captured, we know it is not *yet* captured and can continue with the noalias deduction. Currently, information AAReachability provides is completely pessimistic.
Reviewers: jdoerfert
Reviewed By: jdoerfert
Subscribers: uenoku, sstefan1, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D70233
Summary:
This patch moves various checks from ThreadEdge to new function
TryThreadEdge The rational behind this is that I'd like to use
ThreadEdge without its checks in my upcoming patch.
This patch preserves lightweight checks as assertions in ThreadEdge.
ThreadEdge does not repeat the cost check, however.
Reviewers: wmi
Subscribers: hiraditya, jfb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D70338
After speaking with Sanjay - seeing a number of miscompiles and working
on tracking down a testcase. None of the follow on patches seem to
have helped so far.
This reverts commit 8a0aa5310bccbb42d16d11db090419fcefdd1376.
After speaking with Sanjay - seeing a number of miscompiles and working
on tracking down a testcase. None of the follow on patches seem to
have helped so far.
This reverts commit 7ff57705ba196ce649d6034614b3b9df57e1f84f.
This is mostly NFC, but I removed the setting of the guard's calling convention onto the WC call. Why? Because it was untested, and was producing an ill defined output as the declaration's convention wasn't been changed leaving a mismatch which is UB.
With the widenable condition construct, we have the ability to reason about branches which can be 'widened' (i.e. made to fail more often). We've got a couple o transforms which leverage this. This patch just cleans up the API a bit.
This is prep work for generalizing our definition of a widenable branch slightly. At the moment "br i1 (and A, wc()), ..." is considered widenable, but oddly, neither "br i1 (and wc(), B), ..." or "br i1 wc(), ..." is. That clearly needs addressed, so first, let's centralize the code in one place.
Summary:
Pass down the already accessed ValueInfo to shouldPromoteLocalToGlobal,
to avoid an unnecessary extra index lookup.
Add some assertion checking to confirm we have a non-empty VI when
expected.
Also some misc cleanup, merging the two versions of
doImportAsDefinition, since one was only called by the other, and
unnecessarily passed in a member variable.
Reviewers: steven_wu, pcc, evgeny777
Reviewed By: evgeny777
Subscribers: mehdi_amini, inglorion, hiraditya, dexonsmith, arphaman, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D70337
Summary:
Clean up the code that does GV promotion in the ThinLTO backends.
Specifically, we don't need to check whether we are importing since that
is already checked and handled correctly in shouldPromoteLocalToGlobal.
Simply call shouldPromoteLocalToGlobal, and if it returns true we are
guaranteed that we are promoting, whether or not we are importing (or in
the exporting module). This also makes the handling in getName()
consistent with that in getLinkage(), which checks the DoPromote parameter
regardless of whether we are importing or exporting.
Reviewers: steven_wu, pcc, evgeny777
Subscribers: mehdi_amini, inglorion, hiraditya, dexonsmith, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D70327
This patch introduces a function pass to inject the scalar-to-vector
mappings stored in the TargetLIbraryInfo (TLI) into the Vector
Function ABI (VFABI) variants attribute.
The test is testing the injection for three vector libraries supported
by the TLI (Accelerate, SVML, MASSV).
The pass does not change any of the analysis associated to the
function.
Differential Revision: https://reviews.llvm.org/D70107
ValueInfo has user-defined 'operator bool' which allows incorrect implicit conversion
to GlobalValue::GUID (which is unsigned long). This causes bugs which are hard to
track and should be removed in future.
This reverts commit e511c4b0dff1692c267addf17dce3cebe8f97faa:
Temporarily Revert:
"[SLP] Generalization of stores vectorization."
"[SLP] Fix -Wunused-variable. NFC"
"[SLP] Vectorize jumbled stores."
after fixing the problem with compile time.
This patch adds an assertion check for exported read/write-only
variables to be also in import list for module. If they aren't
we may face linker errors, because read/write-only variables are
internalized in their source modules. The patch also changes
export lists to store ValueInfo instead of GUID for performance
considerations.
Differential revision: https://reviews.llvm.org/D70128
This file lists every pass in LLVM, and is included by Pass.h, which is
very popular. Every time we add, remove, or rename a pass in LLVM, it
caused lots of recompilation.
I found this fact by looking at this table, which is sorted by the
number of times a file was changed over the last 100,000 git commits
multiplied by the number of object files that depend on it in the
current checkout:
recompiles touches affected_files header
342380 95 3604 llvm/include/llvm/ADT/STLExtras.h
314730 234 1345 llvm/include/llvm/InitializePasses.h
307036 118 2602 llvm/include/llvm/ADT/APInt.h
213049 59 3611 llvm/include/llvm/Support/MathExtras.h
170422 47 3626 llvm/include/llvm/Support/Compiler.h
162225 45 3605 llvm/include/llvm/ADT/Optional.h
158319 63 2513 llvm/include/llvm/ADT/Triple.h
140322 39 3598 llvm/include/llvm/ADT/StringRef.h
137647 59 2333 llvm/include/llvm/Support/Error.h
131619 73 1803 llvm/include/llvm/Support/FileSystem.h
Before this change, touching InitializePasses.h would cause 1345 files
to recompile. After this change, touching it only causes 550 compiles in
an incremental rebuild.
Reviewers: bkramer, asbirlea, bollu, jdoerfert
Differential Revision: https://reviews.llvm.org/D70211
Summary:
This temporarily disables the large working set size behavior in profile guided
size optimization due to internal benchmark regressions.
Reviewers: davidxl
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D70207
The attribute is stored at the `FunctionIndex` attribute set, with the
name "vector-function-abi-variant".
The get/set methods of the attribute have assertion to verify that:
1. Each name in the attribute is a valid VFABI mangled name.
2. Each name in the attribute correspond to a function declared in the
module.
Differential Revision: https://reviews.llvm.org/D69976
Summary:
I need to make use of this pass from a driver program that isn't opt.
Therefore this patch moves this pass into the LLVM library so that it is
available for use elsewhere.
There was one function I kept in tools/opt which is exportDebugifyStats()
this is because it's serializing the statistics into a human readable
format and this seemed more in keeping with opt than a library function
Reviewers: vsk, aprantl
Subscribers: mgorny, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69926
Instcombiner pass was erasing trivially dead instruction without updating dependent llvm.dbg.value.
which was not showing programmer current state of variables while debugging.
As a part of this fix I did following,
Iterate throught all the users (llvm.dbg) of a instruction which is trivially dead and set each if them undef, Before deleting the instruction.
Now user will see optimized out, when try to print those variables.
This fixes
https://bugs.llvm.org/show_bug.cgi?id=43893
This is my first fix to llvm.
Patch by kamlesh kumar!
Differential Revision: https://reviews.llvm.org/D69809
We have a vector compare reduction problem seen in PR39665 comment 2:
https://bugs.llvm.org/show_bug.cgi?id=39665#c2
Or slightly reduced here:
define i1 @cmp2(<2 x double> %a0) {
%a = fcmp ogt <2 x double> %a0, <double 1.0, double 1.0>
%b = extractelement <2 x i1> %a, i32 0
%c = extractelement <2 x i1> %a, i32 1
%d = and i1 %b, %c
ret i1 %d
}
SLP would not attempt to turn this into a vector reduction because there is an
artificial lower limit on that transform. We can not completely remove that limit
without inducing regressions though, so this patch just hacks an extra attempt at
creating a 2-way reduction to the end of the analysis.
As shown in the test file, we are still not getting some of the motivating cases,
so follow-on patches will be needed to solve those cases.
Differential Revision: https://reviews.llvm.org/D59710
"[SLP] Generalization of stores vectorization."
"[SLP] Fix -Wunused-variable. NFC"
"[SLP] Vectorize jumbled stores."
As they're causing significant (10-30x) compile time regressions on
vectorizable code.
The primary cause of the compile-time regression is f228b5371647f471853c5fb3e6719823a42fe451.
This reverts commits:
f228b5371647f471853c5fb3e6719823a42fe451
5503455ccb3f5fcedced158332c016c8d3a7fa81
21d498c9c0f32dcab5bc89ac593aa813b533b43a
Summary:
This patch factors out code to clone instructions -- partly for
readability and partly to facilitate an upcoming patch of my own.
Reviewers: wmi
Subscribers: hiraditya, jfb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69861
Summary:
This patch factors out code to merge a basic block with its sole
successor -- partly for readability and partly to facilitate an
upcoming patch of my own.
Reviewers: wmi
Subscribers: hiraditya, jfb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69852
Summary:
This patch factors out common code to update the SSA form in
JumpThreading.cpp -- partly for readability and partly to facilitate
an coming patch of my own.
Reviewers: wmi
Subscribers: hiraditya, jfb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69811
Dependences between two abstract attributes SRC and TRG come naturally in
two flavors:
Either (1) "some" information of SRC is *required* for TRG to derive
information, or (2) SRC is just an *optional* way for TRG to derive
information.
While it is not strictly necessary to distinguish these types
explicitly, it can help us to converge faster, in terms of iterations,
and also cut down the number of `AbstractAttribute::update` calls.
As far as I can tell, we only use optional dependences for liveness so
far but that might change in the future. With this change the Attributor
can be informed about the "dependence class" and it will perform
appropriate actions when an Attribute is set to an invalid state, thus
one that cannot be used by others to derive information from.
Summary:
In order to get context sensitivity from isKnownNonZero we need to
provide a context instruction *and* a dominator tree. The latter is
passed now to which actually allows to remove some initialization code.
Tests taken from PR43833.
Reviewers: uenoku, sstefan1
Subscribers: hiraditya, bollu, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69595
Since SCEV can cache information about location of an instruction, it should be invalidated when the instruction is moved.
There should be similar bug in code sinking part of LICM, it will be fixed in a follow-up change.
Patch Author: Daniil Suchkov
Reviewers: asbirlea, mkazantsev, reames
Reviewed By: asbirlea
Subscribers: hiraditya, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D69370
Summary:
This patch introduces liveness (AAIsDead) for all positions, thus for
all kinds of values. For now, we say an instruction is dead if it would
be removed assuming all users are dead. A call site return is different
as we just look at the users. If all call site returns have been
eliminated, the return values can return undef instead of their original
value, eliminating uses.
We try to recursively delete dead instructions now and we introduce a
simple check interface for use-traversal.
This is the idea tried out in D68626 but implemented in the right way.
Reviewers: uenoku, sstefan1
Subscribers: hiraditya, bollu, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68925
If an attribute did not query any optimistic (=non-fixed) information to
justify its state, we know the attribute state will not change anymore.
Thus, we can indicate an optimistic fixpoint.
We pretended IRPosition came either as mutable or immutable objects
while they are basically always immutable, with a single (existing)
unfortunate exceptions. This patch cleans up the uses to deal with the
immutable version.
For (almost) all IRAttribute we can derive whatever we want for undef
values so it makes sense to provide this functionality in the base
class. At the same time, we probably do not want to annotate them.
Summary:
Delete the BasicBlockPass and BasicBlockManager, all its dependencies and update documentation.
The BasicBlockManager was improperly tested and found to be potentially broken, and was deprecated as of rL373254.
In light of the switch to the new pass manager coming before the next release, this patch is a first cleanup of the LegacyPassManager.
Reviewers: chandlerc, echristo
Subscribers: mehdi_amini, sanjoy.google, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69121
Stores are vectorized with maximum vectorization factor of 16. Patch
tries to improve the situation and use maximal vectorization factor.
Reviewers: spatel, RKSimon, mkuper, hfinkel
Differential Revision: https://reviews.llvm.org/D43582
Summary:
Currently we only forget the loop we added LCSSA phis for. But SCEV
expressions in other loops could also depend on the instruction we added
a PHI for and currently we do not invalidate those expressions. This can
happen when we use ScalarEvolution before converting a function to LCSSA
form. The SCEV expressions will refer to the non-LCSSA value. If this
SCEV expression is then used with the expander, we do not preserve LCSSA
form.
This patch properly forgets the values we created PHIs for. Those need
to be recomputed again. This patch fixes PR43458.
Currently SCEV::verify does not catch this mismatch and any test would
need to run multiple passes to trigger the error (e.g. -loop-reduce
-loop-unroll). I will also look into catching this kind of mismatch in
the verifier. Also, we currently forget the whole loop in LCSSA and I'll
check if we can be more surgical.
Reviewers: efriedma, sanjoy.google, reames
Reviewed By: efriedma
Subscribers: zzheng, hiraditya, javed.absar, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68194
To make IntegerState more flexible but also less error prone we split it
up into (1) incrementing, (2) decrementing, and (3) bit-tracking states.
This adds functionality compared to before and disallows misuse, e.g.,
"incrementing" updates on a bit-tracking state.
Part of the change is a single operator in the base class which
simplifies helper functions that deal with states.
There are certain functional changes but all of which should actually be
corrections.
Summary:
(Split of off D67120)
SizeOpts/MachineSizeOpts changes for profile guided size optimization.
(A second try after previously committed as r375254 and reverted as r375375.)
Subscribers: mgorny, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69409
Summary:
A new function pass (Transforms/CFGuard/CFGuard.cpp) inserts CFGuard checks on
indirect function calls, using either the check mechanism (X86, ARM, AArch64) or
or the dispatch mechanism (X86-64). The check mechanism requires a new calling
convention for the supported targets. The dispatch mechanism adds the target as
an operand bundle, which is processed by SelectionDAG. Another pass
(CodeGen/CFGuardLongjmp.cpp) identifies and emits valid longjmp targets, as
required by /guard:cf. This feature is enabled using the `cfguard` CC1 option.
Reviewers: thakis, rnk, theraven, pcc
Subscribers: ychen, hans, metalcanine, dmajor, tomrittervg, alex, mehdi_amini, mgorny, javed.absar, kristof.beyls, hiraditya, steven_wu, dexonsmith, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D65761
Remove dead virtual functions from vtables with
replaceNonMetadataUsesWith, so that CGProfile metadata gets cleaned up
correctly.
Original commit message:
Currently, it is hard for the compiler to remove unused C++ virtual
functions, because they are all referenced from vtables, which are referenced
by constructors. This means that if the constructor is called from any live
code, then we keep every virtual function in the final link, even if there
are no call sites which can use it.
This patch allows unused virtual functions to be removed during LTO (and
regular compilation in limited circumstances) by using type metadata to match
virtual function call sites to the vtable slots they might load from. This
information can then be used in the global dead code elimination pass instead
of the references from vtables to virtual functions, to more accurately
determine which functions are reachable.
To make this transformation safe, I have changed clang's code-generation to
always load virtual function pointers using the llvm.type.checked.load
intrinsic, instead of regular load instructions. I originally tried writing
this using clang's existing code-generation, which uses the llvm.type.test
and llvm.assume intrinsics after doing a normal load. However, it is possible
for optimisations to obscure the relationship between the GEP, load and
llvm.type.test, causing GlobalDCE to fail to find virtual function call
sites.
The existing linkage and visibility types don't accurately describe the scope
in which a virtual call could be made which uses a given vtable. This is
wider than the visibility of the type itself, because a virtual function call
could be made using a more-visible base class. I've added a new
!vcall_visibility metadata type to represent this, described in
TypeMetadata.rst. The internalization pass and libLTO have been updated to
change this metadata when linking is performed.
This doesn't currently work with ThinLTO, because it needs to see every call
to llvm.type.checked.load in the linkage unit. It might be possible to
extend this optimisation to be able to use the ThinLTO summary, as was done
for devirtualization, but until then that combination is rejected in the
clang driver.
To test this, I've written a fuzzer which generates random C++ programs with
complex class inheritance graphs, and virtual functions called through object
and function pointers of different types. The programs are spread across
multiple translation units and DSOs to test the different visibility
restrictions.
I've also tried doing bootstrap builds of LLVM to test this. This isn't
ideal, because only classes in anonymous namespaces can be optimised with
-fvisibility=default, and some parts of LLVM (plugins and bugpoint) do not
work correctly with -fvisibility=hidden. However, there are only 12 test
failures when building with -fvisibility=hidden (and an unmodified compiler),
and this change does not cause any new failures for either value of
-fvisibility.
On the 7 C++ sub-benchmarks of SPEC2006, this gives a geomean code-size
reduction of ~6%, over a baseline compiled with "-O2 -flto
-fvisibility=hidden -fwhole-program-vtables". The best cases are reductions
of ~14% in 450.soplex and 483.xalancbmk, and there are no code size
increases.
I've also run this on a set of 8 mbed-os examples compiled for Armv7M, which
show a geomean size reduction of ~3%, again with no size increases.
I had hoped that this would have no effect on performance, which would allow
it to awlays be enabled (when using -fwhole-program-vtables). However, the
changes in clang to use the llvm.type.checked.load intrinsic are causing ~1%
performance regression in the C++ parts of SPEC2006. It should be possible to
recover some of this perf loss by teaching optimisations about the
llvm.type.checked.load intrinsic, which would make it worth turning this on
by default (though it's still dependent on -fwhole-program-vtables).
Differential revision: https://reviews.llvm.org/D63932
llvm-svn: 375094
Summary:
There are two cases where a block is merged into its predecessor and the
MergeBlockIntoPredecessor API is not used. Update the API so it can be
reused in the other cases, in order to avoid code duplication.
Cleanup motivated by D68659.
Reviewers: chandlerc, sanjoy.google, george.burgess.iv
Subscribers: llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68670
llvm-svn: 375050
Add a pass to lower is.constant and objectsize intrinsics
This pass lowers is.constant and objectsize intrinsics not simplified by
earlier constant folding, i.e. if the object given is not constant or if
not using the optimized pass chain. The result is recursively simplified
and constant conditionals are pruned, so that dead blocks are removed
even for -O0. This allows inline asm blocks with operand constraints to
work all the time.
The new pass replaces the existing lowering in the codegen-prepare pass
and fallbacks in SDAG/GlobalISEL and FastISel. The latter now assert
on the intrinsics.
Differential Revision: https://reviews.llvm.org/D65280
llvm-svn: 374784
This pass lowers is.constant and objectsize intrinsics not simplified by
earlier constant folding, i.e. if the object given is not constant or if
not using the optimized pass chain. The result is recursively simplified
and constant conditionals are pruned, so that dead blocks are removed
even for -O0. This allows inline asm blocks with operand constraints to
work all the time.
The new pass replaces the existing lowering in the codegen-prepare pass
and fallbacks in SDAG/GlobalISEL and FastISel. The latter now assert
on the intrinsics.
Differential Revision: https://reviews.llvm.org/D65280
llvm-svn: 374743
Even if an argument is captured, we cannot have an effect the function
does not have. This is fine except for the special case of `inalloca` as
it does not behave by the rules.
TODO: Maybe the special rule for `inalloca` is wrong after all.
llvm-svn: 374736
The check for naked/optnone was insufficient for different reasons. We
now check before we initialize an abstract attribute and we do it for
all abstract attributes.
llvm-svn: 374694
Currently, it is hard for the compiler to remove unused C++ virtual
functions, because they are all referenced from vtables, which are referenced
by constructors. This means that if the constructor is called from any live
code, then we keep every virtual function in the final link, even if there
are no call sites which can use it.
This patch allows unused virtual functions to be removed during LTO (and
regular compilation in limited circumstances) by using type metadata to match
virtual function call sites to the vtable slots they might load from. This
information can then be used in the global dead code elimination pass instead
of the references from vtables to virtual functions, to more accurately
determine which functions are reachable.
To make this transformation safe, I have changed clang's code-generation to
always load virtual function pointers using the llvm.type.checked.load
intrinsic, instead of regular load instructions. I originally tried writing
this using clang's existing code-generation, which uses the llvm.type.test
and llvm.assume intrinsics after doing a normal load. However, it is possible
for optimisations to obscure the relationship between the GEP, load and
llvm.type.test, causing GlobalDCE to fail to find virtual function call
sites.
The existing linkage and visibility types don't accurately describe the scope
in which a virtual call could be made which uses a given vtable. This is
wider than the visibility of the type itself, because a virtual function call
could be made using a more-visible base class. I've added a new
!vcall_visibility metadata type to represent this, described in
TypeMetadata.rst. The internalization pass and libLTO have been updated to
change this metadata when linking is performed.
This doesn't currently work with ThinLTO, because it needs to see every call
to llvm.type.checked.load in the linkage unit. It might be possible to
extend this optimisation to be able to use the ThinLTO summary, as was done
for devirtualization, but until then that combination is rejected in the
clang driver.
To test this, I've written a fuzzer which generates random C++ programs with
complex class inheritance graphs, and virtual functions called through object
and function pointers of different types. The programs are spread across
multiple translation units and DSOs to test the different visibility
restrictions.
I've also tried doing bootstrap builds of LLVM to test this. This isn't
ideal, because only classes in anonymous namespaces can be optimised with
-fvisibility=default, and some parts of LLVM (plugins and bugpoint) do not
work correctly with -fvisibility=hidden. However, there are only 12 test
failures when building with -fvisibility=hidden (and an unmodified compiler),
and this change does not cause any new failures for either value of
-fvisibility.
On the 7 C++ sub-benchmarks of SPEC2006, this gives a geomean code-size
reduction of ~6%, over a baseline compiled with "-O2 -flto
-fvisibility=hidden -fwhole-program-vtables". The best cases are reductions
of ~14% in 450.soplex and 483.xalancbmk, and there are no code size
increases.
I've also run this on a set of 8 mbed-os examples compiled for Armv7M, which
show a geomean size reduction of ~3%, again with no size increases.
I had hoped that this would have no effect on performance, which would allow
it to awlays be enabled (when using -fwhole-program-vtables). However, the
changes in clang to use the llvm.type.checked.load intrinsic are causing ~1%
performance regression in the C++ parts of SPEC2006. It should be possible to
recover some of this perf loss by teaching optimisations about the
llvm.type.checked.load intrinsic, which would make it worth turning this on
by default (though it's still dependent on -fwhole-program-vtables).
Differential revision: https://reviews.llvm.org/D63932
llvm-svn: 374539
Summary:
If we insert them from function pass some analysis may be missing or invalid.
Fixes PR42877.
Reviewers: eugenis, leonardchan
Reviewed By: leonardchan
Subscribers: hiraditya, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D68832
> llvm-svn: 374481
Signed-off-by: Vitaly Buka <vitalybuka@google.com>
llvm-svn: 374527
Summary:
If we insert them from function pass some analysis may be missing or invalid.
Fixes PR42877.
Reviewers: eugenis, leonardchan
Reviewed By: leonardchan
Subscribers: hiraditya, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D68832
llvm-svn: 374481
Factor out CodeExtractor's analysis of allocas (for shrinkwrapping
purposes), and allow the analysis to be reused.
This resolves a quadratic compile-time bug observed when compiling
AMDGPUDisassembler.cpp.o.
Pre-patch (Release + LTO clang):
```
---User Time--- --System Time-- --User+System-- ---Wall Time--- --- Name ---
176.5278 ( 57.8%) 0.4915 ( 18.5%) 177.0192 ( 57.4%) 177.4112 ( 57.3%) Hot Cold Splitting
```
Post-patch (ReleaseAsserts clang):
```
---User Time--- --System Time-- --User+System-- ---Wall Time--- --- Name ---
1.4051 ( 3.3%) 0.0079 ( 0.3%) 1.4129 ( 3.2%) 1.4129 ( 3.2%) Hot Cold Splitting
```
Testing: check-llvm, and comparing the AMDGPUDisassembler.cpp.o binary
pre- vs. post-patch.
An alternate approach is to hide CodeExtractorAnalysisCache from clients
of CodeExtractor, and to recompute the analysis from scratch inside of
CodeExtractor::extractCodeRegion(). This eliminates some redundant work
in the shrinkwrapping legality check. However, some clients continue to
exhibit O(n^2) compile time behavior as computing the analysis is O(n).
rdar://55912966
Differential Revision: https://reviews.llvm.org/D68616
llvm-svn: 374089
Summary:
In D65186 and related patches, MustBeExecutedContextExplorer is introduced. This enables us to traverse instructions guaranteed to execute from function entry. If we can know the argument is used as `dereferenceable` or `nonnull` in these instructions, we can mark `dereferenceable` or `nonnull` in the argument definition:
1. Memory instruction (similar to D64258)
Trace memory instruction pointer operand. Currently, only inbounds GEPs are traced.
```
define i64* @f(i64* %a) {
entry:
%add.ptr = getelementptr inbounds i64, i64* %a, i64 1
; (because of inbounds GEP we can know that %a is at least dereferenceable(16))
store i64 1, i64* %add.ptr, align 8
ret i64* %add.ptr ; dereferenceable 8 (because above instruction stores into it)
}
```
2. Propagation from callsite (similar to D27855)
If `deref` or `nonnull` are known in call site parameter attributes we can also say that argument also that attribute.
```
declare void @use3(i8* %x, i8* %y, i8* %z);
declare void @use3nonnull(i8* nonnull %x, i8* nonnull %y, i8* nonnull %z);
define void @parent1(i8* %a, i8* %b, i8* %c) {
call void @use3nonnull(i8* %b, i8* %c, i8* %a)
; Above instruction is always executed so we can say that@parent1(i8* nonnnull %a, i8* nonnull %b, i8* nonnull %c)
call void @use3(i8* %c, i8* %a, i8* %b)
ret void
}
```
Reviewers: jdoerfert, sstefan1, spatel, reames
Reviewed By: jdoerfert
Subscribers: xbolva00, hiraditya, jfb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65402
llvm-svn: 374063
Local linkage is internal or private, and private is a specialization of
internal, so either is fine for all our "local linkage" queries.
llvm-svn: 373986
Summary:
When we iterate over uses of functions and expect them to be call sites,
we now use abstract call sites to allow callback calls.
Reviewers: sstefan1, uenoku
Subscribers: hiraditya, bollu, hfinkel, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67871
llvm-svn: 373985
bcopy is still widely used mainly for network apps. Sadly, LLVM has no optimizations for bcopy, but there are some for memmove.
Since bcopy == memmove, it is profitable to transform bcopy to memmove and use current optimizations for memmove for free here.
llvm-svn: 373537
There are no users that pass in LazyValueInfo, so we can simplify the
function a bit.
Reviewers: brzycki, asbirlea, davide
Reviewed By: davide
Differential Revision: https://reviews.llvm.org/D68297
llvm-svn: 373488
Summary:
This fixes a hole in the handling of devirtualized targets that were
local but need promoting due to devirtualization in another module. We
were not correctly referencing the promoted symbol in some cases. Make
sure the code that updates the name also looks at the ExportedGUIDs set
by utilizing a callback that checks all conditions (the callback
utilized by the internalization/promotion code).
Reviewers: pcc, davidxl, hiraditya
Subscribers: mehdi_amini, Prazek, inglorion, steven_wu, dexonsmith, dang, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68159
llvm-svn: 373485
Initially SLP vectorizer replaced all going-to-be-vectorized
instructions with Undef values. It may break ScalarEvaluation and may
cause a crash.
Reworked SLP vectorizer so that it does not replace vectorized
instructions by UndefValue anymore. Instead vectorized instructions are
marked for deletion inside if BoUpSLP class and deleted upon class
destruction.
Reviewers: mzolotukhin, mkuper, hfinkel, RKSimon, davide, spatel
Subscribers: RKSimon, Gerolf, anemet, hans, majnemer, llvm-commits, sanjoy
Differential Revision: https://reviews.llvm.org/D29641
llvm-svn: 373166
For a runtime loop if we can compute its trip count upperbound:
Don't unroll if:
1. loop is not guaranteed to run either zero or upperbound iterations; and
2. trip count upperbound is less than UnrollMaxUpperBound
Unless user or TTI asked to do so.
If unrolling, limit unroll factor to loop's trip count upperbound.
Differential Revision: https://reviews.llvm.org/D62989
Change-Id: I6083c46a9d98b2e22cd855e60523fdc5a4929c73
llvm-svn: 373017