Commit Graph

20 Commits

Author SHA1 Message Date
Lang Hames
d4a8089f03 [ORC] Update symbol lookup to use a single callback with a required symbol state
rather than two callbacks.

The asynchronous lookup API (which the synchronous lookup API wraps for
convenience) used to take two callbacks: OnResolved (called once all requested
symbols had an address assigned) and OnReady to be called once all requested
symbols were safe to access). This patch updates the asynchronous lookup API to
take a single 'OnComplete' callback and a required state (SymbolState) to
determine when the callback should be made. This simplifies the common use case
(where the client is interested in a specific state) and will generalize neatly
as new states are introduced to track runtime initialization of symbols.

Clients who were making use of both callbacks in a single query will now need to
issue two queries (one for SymbolState::Resolved and another for
SymbolState::Ready). Synchronous lookup API clients who were explicitly passing
the WaitOnReady argument will now need neeed to pass a SymbolState instead (for
'WaitOnReady == true' use SymbolState::Ready, for 'WaitOnReady == false' use
SymbolState::Resolved). Synchronous lookup API clients who were using default
arugment values should see no change.

llvm-svn: 362832
2019-06-07 19:33:51 +00:00
Lang Hames
b12867230c [ORC] Allow JITDylib definition generators to return Errors.
Background: A definition generator can be attached to a JITDylib to generate
new definitions in response to queries. For example: a generator that forwards
calls to dlsym can map symbols from a dynamic library into the JIT process on
demand.

If definition generation fails then the generator should be able to return an
error. This allows the JIT API to distinguish between the case where a
generator does not provide a definition, and the case where it was not able to
determine whether it provided a definition due to an error.

The immediate motivation for this is cross-process symbol lookups: If the
remote-lookup generator is attached to a JITDylib early in the search list, and
if a generator failure is misinterpreted as "no definition in this JITDylib" then
lookup may continue and bind to a different definition in a later JITDylib, which
is a bug.

llvm-svn: 359521
2019-04-30 00:03:26 +00:00
Chandler Carruth
2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
Lang Hames
6a2a889b8a [ORC] Tidy up JITSymbolFlags to remove the need for some explicit static_casts.
Removes the implicit conversion to the underlying type for
JITSymbolFlags::FlagNames and replaces it with some bitwise and comparison
operators.

llvm-svn: 341282
2018-09-02 01:28:26 +00:00
Lang Hames
b8b8de423d [ORC] Remove a stray debugging output line left in a unit test.
llvm-svn: 341155
2018-08-31 00:53:53 +00:00
Lang Hames
6cadc7c06b [ORC] Replace lookupFlags in JITSymbolResolver with getResponsibilitySet.
The new method name/behavior more closely models the way it was being used.
It also fixes an assertion that can occur when using the new ORC Core APIs,
where flags alone don't necessarily provide enough context to decide whether
the caller is responsible for materializing a given symbol (which was always
the reason this API existed).

The default implementation of getResponsibilitySet uses lookupFlags to determine
responsibility as before, so existing JITSymbolResolvers should continue to
work.

llvm-svn: 340874
2018-08-28 21:18:05 +00:00
Lang Hames
d5f56c5979 [ORC] Rename VSO to JITDylib.
VSO was a little close to VDSO (an acronym on Linux for Virtual Dynamic Shared
Object) for comfort. It also risks giving the impression that instances of this
class could be shared between ExecutionSessions, which they can not.

JITDylib seems moderately less confusing, while still hinting at how this
class is intended to be used, i.e. as a JIT-compiled stand-in for a dynamic
library (code that would have been a dynamic library if you had wanted to
compile it ahead of time).

llvm-svn: 340084
2018-08-17 21:18:18 +00:00
Lang Hames
a48d108353 Re-apply r337595 with fix for LLVM_ENABLE_THREADS=Off.
llvm-svn: 337626
2018-07-20 22:22:19 +00:00
Reid Kleckner
7ed83591c2 Revert r337595 "[ORC] Add new symbol lookup methods to ExecutionSessionBase in preparation for"
Breaks the build with LLVM_ENABLE_THREADS=OFF.

llvm-svn: 337608
2018-07-20 20:20:45 +00:00
Lang Hames
732d116a96 [ORC] Add new symbol lookup methods to ExecutionSessionBase in preparation for
deprecating SymbolResolver and AsynchronousSymbolQuery.

Both lookup overloads take a VSO search order to perform the lookup. The first
overload is non-blocking and takes OnResolved and OnReady callbacks. The second
is blocking, takes a boolean flag to indicate whether to wait until all symbols
are ready, and returns a SymbolMap. Both overloads take a RegisterDependencies
function to register symbol dependencies (if any) on the query.

llvm-svn: 337595
2018-07-20 18:31:53 +00:00
Lang Hames
d4df0f1733 [ORC] Simplify VSO::lookupFlags to return the flags map.
This discards the unresolved symbols set and returns the flags map directly
(rather than mutating it via the first argument).

The unresolved symbols result made it easy to chain lookupFlags calls, but such
chaining should be rare to non-existant (especially now that symbol resolvers
are being deprecated) so the simpler method signature is preferable.

llvm-svn: 337594
2018-07-20 18:31:52 +00:00
Lang Hames
fd0c1e7169 [ORC] Replace SymbolResolvers in the new ORC layers with search orders on VSOs.
A search order is a list of VSOs to be searched linearly to find symbols. Each
VSO now has a search order that will be used when fixing up definitions in that
VSO. Each VSO's search order defaults to just that VSO itself.

This is a first step towards removing symbol resolvers from ORC altogether. In
practice symbol resolvers tended to be used to implement a search order anyway,
sometimes with additional programatic generation of symbols. Now that VSOs
support programmatic generation of definitions via fallback generators, search
orders provide a cleaner way to achieve the desired effect (while removing a lot
of boilerplate).

llvm-svn: 337593
2018-07-20 18:31:50 +00:00
Lang Hames
d261e1258c [ORC] Rewrite the VSO symbol table yet again. Update related utilities.
VSOs now track dependencies for materializing symbols. Each symbol must have its
dependencies registered with the VSO prior to finalization. Usually this will
involve registering the dependencies returned in
AsynchronousSymbolQuery::ResolutionResults for queries made while linking the
symbols being materialized.

Queries against symbols are notified that a symbol is ready once it and all of
its transitive dependencies are finalized, allowing compilation work to be
broken up and moved between threads without queries returning until their
symbols fully safe to access / execute.

Related utilities (VSO, MaterializationUnit, MaterializationResponsibility) are
updated to support dependence tracking and more explicitly track responsibility
for symbols from the point of definition until they are finalized.

llvm-svn: 332541
2018-05-16 22:24:30 +00:00
Lang Hames
67feadb2c7 [ORC] Add a MaterializationResponsibility class to track responsibility for
materializing function definitions.

MaterializationUnit instances are responsible for resolving and finalizing
symbol definitions when their materialize method is called. By contract, the
MaterializationUnit must materialize all definitions it is responsible for and
no others. If it can not materialize all definitions (because of some error)
then it must notify the associated VSO about each definition that could not be
materialized. The MaterializationResponsibility class tracks this
responsibility, asserting that all required symbols are resolved and finalized,
and that no extraneous symbols are resolved or finalized. In the event of an
error it provides a convenience method for notifying the VSO about each
definition that could not be materialized.

llvm-svn: 330142
2018-04-16 18:05:24 +00:00
Lang Hames
3fdfc04e53 [ORC] Create a new SymbolStringPool by default in ExecutionSession constructor.
This makes the common case of constructing an ExecutionSession tidier.

llvm-svn: 329013
2018-04-02 20:57:56 +00:00
Lang Hames
4cca7d229e [ORC] Rename SymbolSource to MaterializationUnit, and make the materialization
operation all-or-nothing, rather than allowing materialization on a per-symbol
basis.

This addresses a shortcoming of per-symbol materialization: If a
MaterializationUnit (/SymbolSource) wants to materialize more symbols than
requested (which is likely: most materializers will want to materialize whole
modules) then it needs a way to notify the symbol table about the extra symbols
being materialized. This process (checking what has been requested against what
is being provided and notifying the symbol table about the difference) has to
be repeated at every level of the JIT stack. Making materialization
all-or-nothing eliminates this issue, simplifying both materializer
implementations and the symbol table (VSO class) API. The cost is that
per-symbol materialization (e.g. for individual symbols in a module) now
requires multiple MaterializationUnits.

llvm-svn: 327946
2018-03-20 03:49:29 +00:00
Lang Hames
e833fe8ec3 [ORC] Switch to shared_ptr ownership for AsynchronousSymbolQueries.
Queries need to stay alive until each owner has set the values they are
responsible for.

llvm-svn: 325179
2018-02-14 22:12:56 +00:00
Lang Hames
c8a74a0448 [ORC] Refactor the various lookupFlags methods to return the flags map via the
first argument.

This makes lookupFlags more consistent with lookup (which takes the query as the
first argument) and composes better in practice, since lookups are usually
linearly chained: Each lookupFlags can populate the result map based on the
symbols not found in the previous lookup. (If the maps were returned rather than
passed by reference there would have to be a merge step at the end).

llvm-svn: 323398
2018-01-25 01:43:00 +00:00
Lang Hames
d78ba0d4b2 [ORC] Add helpers for building orc::SymbolResolvers from legacy findSymbol-style
functions/methods that return JITSymbols.

lookupFlagsWithLegacyFn takes a SymbolNameSet and a legacy lookup function and
returns a LookupFlagsResult. It uses the legacy lookup function to search for
each symbol. If found, getFlags is called on the symbol and the flags added to
the SymbolFlags map. If not found, the symbol is added to the SymbolsNotFound
set.

lookupWithLegacyFn takes an AsynchronousSymbolQuery, a SymbolNameSet and a
legacy lookup function. Each symbol in the SymbolNameSet is searched for via the
legacy lookup function. If it is found, its getAddress function is called
(triggering materialization if it has not happened already) and the resulting
mapping stored in the query. If it is not found the symbol is added to the
unresolved symbols set which is returned at the end of the function. If an
error occurs during legacy lookup or materialization it is passed to the
query via setFailed and the function returns immediately.

llvm-svn: 323388
2018-01-24 23:09:07 +00:00
Lang Hames
635fd9092b [ORC] Add orc::SymbolResolver, a Orc/Legacy API interop header, and an
orc::SymbolResolver to JITSymbolResolver adapter.

The new orc::SymbolResolver interface uses asynchronous queries for better
performance. (Asynchronous queries with bulk lookup minimize RPC/IPC overhead,
support parallel incoming queries, and expose more available work for
distribution). Existing ORC layers will soon be updated to use the
orc::SymbolResolver API rather than the legacy llvm::JITSymbolResolver API.

Because RuntimeDyld still uses JITSymbolResolver, this patch also includes an
adapter that wraps an orc::SymbolResolver with a JITSymbolResolver API.

llvm-svn: 323073
2018-01-22 03:00:31 +00:00