Add a helper function getDebugInfoVersionFromModule to return the debug info
version number for a module.
"Verifier/module-flags-1.ll" checks for verification errors.
It will seg fault when calling getDebugInfoVersionFromModule because of the
incorrect format for module flags in the testing case. We make
getModuleFlagsMetadata more robust by checking for error conditions.
PR17982
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196158 91177308-0d34-0410-b5e6-96231b3b80d8
When a block is unreachable, asking its dom tree descendants should
return the empty set. However, the computation of the descendants
was causing a segmentation fault because the dom tree node we get
from the basic block is initially NULL.
Fixed by adding a test for a valid dom tree node before we iterate.
The patch also adds some unit tests to the existing dom tree tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196099 91177308-0d34-0410-b5e6-96231b3b80d8
to be a bit more sensible. The public interface now is first followed by
the implementation details.
This also resolves a FIXME to make something private -- it was already
possible as the one special caller was already a friend.
No functionality changed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196095 91177308-0d34-0410-b5e6-96231b3b80d8
target independent.
Most of the x86 specific stackmap/patchpoint handling was necessitated by the
use of the native address-mode format for frame index operands. PEI has now
been modified to treat stackmap/patchpoint similarly to DEBUG_INFO, allowing
us to use a simple, platform independent register/offset pair for frame
indexes on stackmap/patchpoints.
Notes:
- Folding is now platform independent and automatically supported.
- Emiting patchpoints with direct memory references now just involves calling
the TargetLoweringBase::emitPatchPoint utility method from the target's
XXXTargetLowering::EmitInstrWithCustomInserter method. (See
X86TargetLowering for an example).
- No more ugly platform-specific operand parsers.
This patch shouldn't change the generated output for X86.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195944 91177308-0d34-0410-b5e6-96231b3b80d8
only user was an ancient SCC printing bit of the opt tool which really
should be walking the call graph the same way the CGSCC pass manager
does.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195800 91177308-0d34-0410-b5e6-96231b3b80d8
class name. I think we're no longer using any compilers with
sufficiently broken ICN for this use case, but I'll watch the bots and
introduce a typedef without a reserved name if any yell at me.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195793 91177308-0d34-0410-b5e6-96231b3b80d8
doxygen comments, make existing comments doxygen comments etc.
Also, switch commented-out debug helpers to #if-0-ed out debug helpers.
No functionality changed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195783 91177308-0d34-0410-b5e6-96231b3b80d8
This patch adds the counter-part to DominatorTree::getDescendants.
It also fixes a couple of comments I noticed out of date in the
DominatorTree class.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195778 91177308-0d34-0410-b5e6-96231b3b80d8
happy with but GCC complains about. I'm assuming both compilers are
correct and these are optional in C++11 because I'm too tired to read
the standard. ;]
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195748 91177308-0d34-0410-b5e6-96231b3b80d8
of the two analysis managers into a CRTP base class that can be shared
and re-used in building any analysis manager. This will in turn simplify
adding yet another analysis manager to the system.
The base class provides all of the interface sugar for the analysis
manager delegating the functionality back through DerivedT methods which
operate on simple pass IDs. It also provides the pass registration,
storage, and lookup system which is common across the various
formulations of analysis managers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195747 91177308-0d34-0410-b5e6-96231b3b80d8
CallGraph.
This makes the CallGraph a totally generic analysis object that is the
container for the graph data structure and the primary interface for
querying and manipulating it. The pass logic is separated into its own
class. For compatibility reasons, the pass provides wrapper methods for
most of the methods on CallGraph -- they all just forward.
This will allow the new pass manager infrastructure to provide its own
analysis pass that constructs the same CallGraph object and makes it
available. The idea is that in the new pass manager, the analysis pass's
'run' method returns a concrete analysis 'result'. Here, that result is
a 'CallGraph'. The 'run' method will typically do only minimal work,
deferring much of the work into the implementation of the result object
in order to be lazy about computing things, but when (like DomTree)
there is *some* up-front computation, the analysis does it prior to
handing the result back to the querying pass.
I know some of this is fairly ugly. I'm happy to change it around if
folks can suggest a cleaner interim state, but there is going to be some
amount of unavoidable ugliness during the transition period. The good
thing is that this is very limited and will naturally go away when the
old pass infrastructure goes away. It won't hang around to bother us
later.
Next up is the initial new-PM-style call graph analysis. =]
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195722 91177308-0d34-0410-b5e6-96231b3b80d8
that lets the analysis and graph types be separate and the graph
computed from the analysis through some arbitrary user-supplied code.
This will allow a call graph to an independent entity from the pass
which creates it which is necessary for the new pass manager.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195717 91177308-0d34-0410-b5e6-96231b3b80d8
changes to it. No functionality changed.
You may wonder why on earth touching this code is involved in the pass
manager work as indicated by my lovely '[PM]' tag? Let me tell you
a story.
<redacted>
Yea, it's too long of a story. Let us say that there are yaks, many of
them. I am busy shaving them as fast as I can.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195715 91177308-0d34-0410-b5e6-96231b3b80d8
A Direct stack map location records the address of frame index. This
address is itself the value that the runtime requested. This differs
from IndirectMemRefOp locations, which refer to a stack locations from
which the requested values must be loaded. Direct locations can
directly communicate the address if an alloca, while IndirectMemRefOp
handle register spills.
For example:
entry:
%a = alloca i64...
llvm.experimental.stackmap(i32 <ID>, i32 <shadowBytes>, i64* %a)
Since both the alloca and stackmap intrinsic are in the entry block,
and the intrinsic takes the address of the alloca, the runtime can
assume that LLVM will not substitute alloca with any intervening
value. This must be verified by the runtime by checking that the stack
map's location is a Direct location type. The runtime can then
determine the alloca's relative location on the stack immediately after
compilation, or at any time thereafter. This differs from Register and
Indirect locations, because the runtime can only read the values in
those locations when execution reaches the instruction address of the
stack map.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195712 91177308-0d34-0410-b5e6-96231b3b80d8
spacing around the '*' in pointer types. Will let me use clang-format on
subsequent changes without introducing any noise. No functionality
changed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195708 91177308-0d34-0410-b5e6-96231b3b80d8
whitespace, and a couple of argument name fixes before I start hacking
on this code. No functionality changed here.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195699 91177308-0d34-0410-b5e6-96231b3b80d8
This matches other empty() container functions in LLVM.
No actual usage problems discovered in this instance.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195562 91177308-0d34-0410-b5e6-96231b3b80d8
proxy. This lets a function pass query a module analysis manager.
However, the interface is const to indicate that only cached results can
be safely queried.
With this, I think the new pass manager is largely functionally complete
for modules and analyses. Still lots to test, and need to generalize to
SCCs and Loops, and need to build an adaptor layer to support the use of
existing Pass objects in the new managers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195538 91177308-0d34-0410-b5e6-96231b3b80d8
results.
This is the last piece of infrastructure needed to effectively support
querying *up* the analysis layers. The next step will be to introduce
a proxy which provides access to those layers with appropriate use of
const to direct queries to the safe interface.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195525 91177308-0d34-0410-b5e6-96231b3b80d8
one function's analyses are invalidated at a time. Also switch the
preservation of the proxy to *fully* preserve the lower (function)
analyses.
Combined, this gets both upward and downward analysis invalidation to
a point I'm happy with:
- A function pass invalidates its function analyses, and its parent's
module analyses.
- A module pass invalidates all of its functions' analyses including the
set of which functions are in the module.
- A function pass can preserve a module analysis pass.
- If all function passes preserve a module analysis pass, that
preservation persists. If any doesn't the module analysis is
invalidated.
- A module pass can opt into managing *all* function analysis
invalidation itself or *none*.
- The conservative default is none, and the proxy takes the maximally
conservative approach that works even if the set of functions has
changed.
- If a module pass opts into managing function analysis invalidation it
has to propagate the invalidation itself, the proxy just does nothing.
The only thing really missing is a way to query for a cached analysis or
nothing at all. With this, function passes can more safely request
a cached module analysis pass without fear of it accidentally running
part way through.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195519 91177308-0d34-0410-b5e6-96231b3b80d8
We can share the implementation between StripSymbols and dropping debug info
for metadata versions that do not match.
Also update the comments to match the implementation. A follow-on patch will
drop the "Debug Info Version" module flag in StripDebugInfo.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195505 91177308-0d34-0410-b5e6-96231b3b80d8
Improvements over r195317:
- Set/restore EnableFastISel flag instead of just running FastISel within
SelectAllBasicBlocks; the flag is checked in various places, and
FastISel won't run properly if those places don't do the right thing.
- Test looks for normal ISel versus FastISel behavior, and not
something more subtle that doesn't work everywhere.
Based on work by Andrea Di Biagio.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195491 91177308-0d34-0410-b5e6-96231b3b80d8
run methods of the analysis passes.
Also generalizes and re-uses the SFINAE for transformation passes so
that users can write an analysis pass and only accept an analysis
manager if that is useful to their pass.
This completes the plumbing to make an analysis manager available
through every pass's run method if desired so that passes no longer need
to be constructed around them.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195451 91177308-0d34-0410-b5e6-96231b3b80d8
several templates. The previous order didn't make any sense as it
separated 'IRUnitT' and 'AnalysisManagerT', the types which are
essentially paired and passed along together throughout the layers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195450 91177308-0d34-0410-b5e6-96231b3b80d8
Since the analysis managers were split into explicit function and module
analysis managers, it is now completely trivial to specify this when
building up the concept and model types explicitly, and it is impossible
to end up with a type error at run time. We instantiate a template when
registering a pass that will enforce the requirement at a type-system
level, and we produce a dynamic error on all the other query paths to
the analysis manager if the pass in question isn't registered.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195447 91177308-0d34-0410-b5e6-96231b3b80d8
This is supposed to be the whole type of the IR unit, and so we
shouldn't pass a pointer to it but rather the value itself. In turn, we
need to provide a 'Module *' as that type argument (for example). This
will become more relevant with SCCs or other units which may not be
passed as a pointer type, but also brings consistency with the
transformation pass templates.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195445 91177308-0d34-0410-b5e6-96231b3b80d8
We already have a method for returning one loop latch but for some
reason no one has committed one for returning loop latches in the case
where there are multiple latches.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195410 91177308-0d34-0410-b5e6-96231b3b80d8
<def,dead> ones.
Add an assertion to make sure we catch this in the future.
Fixes <rdar://problem/15464559>.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195401 91177308-0d34-0410-b5e6-96231b3b80d8
rather than the constructors of passes.
This simplifies the APIs of passes significantly and removes an error
prone pattern where the *same* manager had to be given to every
different layer. With the new API the analysis managers themselves will
have to be cross connected with proxy analyses that allow a pass at one
layer to query for the analysis manager of another layer. The proxy will
both expose a handle to the other layer's manager and it will provide
the invalidation hooks to ensure things remain consistent across layers.
Finally, the outer-most analysis manager has to be passed to the run
method of the outer-most pass manager. The rest of the propagation is
automatic.
I've used SFINAE again to allow passes to completely disregard the
analysis manager if they don't need or want to care. This helps keep
simple things simple for users of the new pass manager.
Also, the system specifically supports passing a null pointer into the
outer-most run method if your pass pipeline neither needs nor wants to
deal with analyses. I find this of dubious utility as while some
*passes* don't care about analysis, I'm not sure there are any
real-world users of the pass manager itself that need to avoid even
creating an analysis manager. But it is easy to support, so there we go.
Finally I renamed the module proxy for the function analysis manager to
the more verbose but less confusing name of
FunctionAnalysisManagerModuleProxy. I hate this name, but I have no idea
what else to name these things. I'm expecting in the fullness of time to
potentially have the complete cross product of types at the proxy layer:
{Module,SCC,Function,Loop,Region}AnalysisManager{Module,SCC,Function,Loop,Region}Proxy
(except for XAnalysisManagerXProxy which doesn't make any sense)
This should make it somewhat easier to do the next phases which is to
build the upward proxy and get its invalidation correct, as well as to
make the invalidation within the Module -> Function mapping pass be more
fine grained so as to invalidate fewer fuction analyses.
After all of the proxy analyses are done and the invalidation working,
I'll finally be able to start working on the next two fun fronts: how to
adapt an existing pass to work in both the legacy pass world and the new
one, and building the SCC, Loop, and Region counterparts. Fun times!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195400 91177308-0d34-0410-b5e6-96231b3b80d8
This patch is a rewrite of the original patch commited in r194542. Instead of
relying on the type legalizer to do the splitting for us, we now peform the
splitting ourselves in the DAG combiner. This is necessary for the case where
the vector mask is a legal type after promotion and still wouldn't require
splitting.
Patch by: Juergen Ributzka
NOTE: This is a candidate for the 3.4 branch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195397 91177308-0d34-0410-b5e6-96231b3b80d8
It broke, at least, i686 target. It is reproducible with "llc -mtriple=i686-unknown".
FYI, it didn't appear to add either "-O0" or "-fast-isel".
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195339 91177308-0d34-0410-b5e6-96231b3b80d8
it is completely optional, and sink the logic for handling the preserved
analysis set into it.
This allows us to implement the delegation logic desired in the proxy
module analysis for the function analysis manager where if the proxy
itself is preserved we assume the set of functions hasn't changed and we
do a fine grained invalidation by walking the functions in the module
and running the invalidate for them all at the manager level and letting
it try to invalidate any passes.
This in turn makes it blindingly obvious why we should hoist the
invalidate trait and have two collections of results. That allows
handling invalidation for almost all analyses without indirect calls and
it allows short circuiting when the preserved set is all.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195338 91177308-0d34-0410-b5e6-96231b3b80d8
type and detect whether or not it provides an 'invalidate' member the
analysis manager should use.
This lets the overwhelming common case of *not* caring about custom
behavior when an analysis is invalidated be the the obvious default
behavior with no code written by the author of an analysis. Only when
they write code specifically to handle invalidation does it get used.
Both cases are actually covered by tests here. The test analysis uses
the default behavior, and the proxy module analysis actually has custom
behavior on invalidation that is firing correctly. (In fact, this is the
analysis which was the primary motivation for having custom invalidation
behavior in the first place.)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195332 91177308-0d34-0410-b5e6-96231b3b80d8
This proxy will fill the role of proxying invalidation events down IR
unit layers so that when a module changes we correctly invalidate
function analyses. Currently this is a very coarse solution -- any
change blows away the entire thing -- but the next step is to make
invalidation handling more nuanced so that we can propagate specific
amounts of invalidation from one layer to the next.
The test is extended to place a module pass between two function pass
managers each of which have preserved function analyses which get
correctly invalidated by the module pass that might have changed what
functions are even in the module.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195304 91177308-0d34-0410-b5e6-96231b3b80d8
Enhance the tests to actually require moves in C++11 mode, in addition
to testing the moved-from state. Further enhance the tests to cover
copy-assignment into a moved-from object and moving a large-state
object. (Note that we can't really test small-state vs. large-state as
that isn't an observable property of the API really.) This should finish
addressing review on r195239.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195261 91177308-0d34-0410-b5e6-96231b3b80d8
This adds a new set-like type which represents a set of preserved
analysis passes. The set is managed via the opaque PassT::ID() void*s.
The expected convenience templates for interacting with specific passes
are provided. It also supports a symbolic "all" state which is
represented by an invalid pointer in the set. This state is nicely
saturating as it comes up often. Finally, it supports intersection which
is used when finding the set of preserved passes after N different
transforms.
The pass API is then changed to return the preserved set rather than
a bool. This is much more self-documenting than the previous system.
Returning "none" is a conservatively correct solution just like
returning "true" from todays passes and not marking any passes as
preserved. Passes can also be dynamically preserved or not throughout
the run of the pass, and whatever gets returned is the binding state.
Finally, preserving "all" the passes is allowed for no-op transforms
that simply can't harm such things.
Finally, the analysis managers are changed to instead of blindly
invalidating all of the analyses, invalidate those which were not
preserved. This should rig up all of the basic preservation
functionality. This also correctly combines the preservation moving up
from one IR-layer to the another and the preservation aggregation across
N pass runs. Still to go is incrementally correct invalidation and
preservation across IR layers incrementally during N pass runs. That
will wait until we have a device for even exposing analyses across IR
layers.
While the core of this change is obvious, I'm not happy with the current
testing, so will improve it to cover at least some of the invalidation
that I can test easily in a subsequent commit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195241 91177308-0d34-0410-b5e6-96231b3b80d8
Somehow, this ADT got missed which is moderately terrifying considering
the efficiency of move for it.
The code to implement move semantics for it is pretty horrible
currently but was written to reasonably closely match the rest of the
code. Unittests that cover both copying and moving (at a basic level)
added.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195239 91177308-0d34-0410-b5e6-96231b3b80d8
The FunctionPassManager is now itself a function pass. When run over
a function, it runs all N of its passes over that function. This is the
1:N mapping in the pass dimension only. This allows it to be used in
either a ModulePassManager or potentially some other manager that
works on IR units which are supersets of Functions.
This commit also adds the obvious adaptor to map from a module pass to
a function pass, running the function pass across every function in the
module.
The test has been updated to use this new pattern.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195192 91177308-0d34-0410-b5e6-96231b3b80d8
Instead of permanently outputting "MVLL" as the file checksum, clang
will create gcno and gcda checksums by hashing the destination block
numbers of every arc. This allows for llvm-cov to check if the two gcov
files are synchronized.
Regenerated the test files so they contain the checksum. Also added
negative test to ensure error when the checksums don't match.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195191 91177308-0d34-0410-b5e6-96231b3b80d8
a module-specific interface. This is the first of many steps necessary
to generalize the infrastructure such that we can support both
a Module-to-Function and Module-to-SCC-to-Function pass manager
nestings.
After a *lot* of attempts that never worked and didn't even make it to
a committable state, it became clear that I had gotten the layering
design of analyses flat out wrong. Four days later, I think I have most
of the plan for how to correct this, and I'm starting to reshape the
code into it. This is just a baby step I'm afraid, but starts separating
the fundamentally distinct concepts of function analysis passes and
module analysis passes so that in subsequent steps we can effectively
layer them, and have a consistent design for the eventual SCC layer.
As part of this, I've started some interface changes to make passes more
regular. The module pass accepts the module in the run method, and some
of the constructor parameters are gone. I'm still working out exactly
where constructor parameters vs. method parameters will be used, so
I expect this to fluctuate a bit.
This actually makes the invalidation less "correct" at this phase,
because now function passes don't invalidate module analysis passes, but
that was actually somewhat of a misfeature. It will return in a better
factored form which can scale to other units of IR. The documentation
has gotten less verbose and helpful.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195189 91177308-0d34-0410-b5e6-96231b3b80d8
Added constness to methods that shouldn't modify objects. Replaced
operator[] lookup in maps with find() instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195151 91177308-0d34-0410-b5e6-96231b3b80d8
This is the first step to fix pr17918.
It extends the .section directive a bit, inspired by what the ELF one looks
like. The problem with using linkonce is that given
.section foo
.linkonce....
.section foo
.linkonce
we would already have switched sections when getting to .linkonce. The cleanest
solution seems to be to add the comdat information in the .section itself.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195148 91177308-0d34-0410-b5e6-96231b3b80d8
Hard-coded operand indices were scattered throughout lowering stages
and layers. It was super bug prone.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195093 91177308-0d34-0410-b5e6-96231b3b80d8
This patch removes most of the trivial cases of weak vtables by pinning them to
a single object file. The memory leaks in this version have been fixed. Thanks
Alexey for pointing them out.
Differential Revision: http://llvm-reviews.chandlerc.com/D2068
Reviewed by Andy
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195064 91177308-0d34-0410-b5e6-96231b3b80d8
This change is incorrect. If you delete virtual destructor of both a base class
and a subclass, then the following code:
Base *foo = new Child();
delete foo;
will not cause the destructor for members of Child class. As a result, I observe
plently of memory leaks. Notable examples I investigated are:
ObjectBuffer and ObjectBufferStream, AttributeImpl and StringSAttributeImpl.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194997 91177308-0d34-0410-b5e6-96231b3b80d8
We used to depend on running processModule before the other public functions
such as processDeclare, processValue and processLocation. We are now relaxing
the constraint by adding a module argument to the three functions and
letting the three functions to initialize the type map. This will be used in
a follow-on patch that collects nodes reachable from a Function.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194973 91177308-0d34-0410-b5e6-96231b3b80d8
This adds a boolean member variable to the PassManagerBuilder to control loop
rerolling (just like we have for unrolling and the various vectorization
options). This is necessary for control by the frontend. Loop rerolling remains
disabled by default at all optimization levels.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194966 91177308-0d34-0410-b5e6-96231b3b80d8
This change is the first in a series of changes improving LLVM's Block
Frequency propogation implementation to not lose probability mass in
branchy code when propogating block frequency information from a basic
block to its successors. This patch is a simple infrastructure
improvement that does not actually modify the block frequency
algorithm. The specific changes are:
1. Changes the division algorithm used when scaling block frequencies by
branch probabilities to a short division algorithm. This gives us the
remainder for free as well as provides a nice speed boost. When I
benched the old routine and the new routine on a Sandy Bridge iMac with
disabled turbo mode performing 8192 iterations on an array of length
32768, I saw ~600% increase in speed in mean/median performance.
2. Exposes a scale method that returns a remainder. This is important so
we can ensure that when we scale a block frequency by some branch
probability BP = N/D, the remainder from the division by D can be
retrieved and propagated to other children to ensure no probability mass
is lost (more to come on this).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194950 91177308-0d34-0410-b5e6-96231b3b80d8
AnalysisManager. All this method did was assert something and we have
a perfectly good way to trigger that assert from the query path.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194947 91177308-0d34-0410-b5e6-96231b3b80d8
Implementing this on bigendian platforms could get strange. I added a
target hook, getStackSlotRange, per Jakob's recommendation to make
this as explicit as possible.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194942 91177308-0d34-0410-b5e6-96231b3b80d8
This adds a loop rerolling pass: the opposite of (partial) loop unrolling. The
transformation aims to take loops like this:
for (int i = 0; i < 3200; i += 5) {
a[i] += alpha * b[i];
a[i + 1] += alpha * b[i + 1];
a[i + 2] += alpha * b[i + 2];
a[i + 3] += alpha * b[i + 3];
a[i + 4] += alpha * b[i + 4];
}
and turn them into this:
for (int i = 0; i < 3200; ++i) {
a[i] += alpha * b[i];
}
and loops like this:
for (int i = 0; i < 500; ++i) {
x[3*i] = foo(0);
x[3*i+1] = foo(0);
x[3*i+2] = foo(0);
}
and turn them into this:
for (int i = 0; i < 1500; ++i) {
x[i] = foo(0);
}
There are two motivations for this transformation:
1. Code-size reduction (especially relevant, obviously, when compiling for
code size).
2. Providing greater choice to the loop vectorizer (and generic unroller) to
choose the unrolling factor (and a better ability to vectorize). The loop
vectorizer can take vector lengths and register pressure into account when
choosing an unrolling factor, for example, and a pre-unrolled loop limits that
choice. This is especially problematic if the manual unrolling was optimized
for a machine different from the current target.
The current implementation is limited to single basic-block loops only. The
rerolling recognition should work regardless of how the loop iterations are
intermixed within the loop body (subject to dependency and side-effect
constraints), but the significant restriction is that the order of the
instructions in each iteration must be identical. This seems sufficient to
capture all current use cases.
This pass is not currently enabled by default at any optimization level.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194939 91177308-0d34-0410-b5e6-96231b3b80d8
