they're needed.
Prior to this patch objects were loaded (via RuntimeDyld::loadObject) when they
were added to the ObjectLinkingLayer, but were not relocated and finalized until
a symbol address was requested. In the interim, another object could be loaded
and finalized with the same memory manager, causing relocation/finalization of
the first object to fail (as the first finalization call may have marked the
allocated memory for the first object read-only).
By deferring the loadObject call (and subsequent memory allocations) until an
object file is needed we can avoid prematurely finalizing memory.
llvm-svn: 258185
llvm\unittests\ExecutionEngine\Orc\ObjectLinkingLayerTest.cpp(115) : error C2327: 'llvm::OrcExecutionTest::TM' : is not a type name, static, or enumerator
llvm\unittests\ExecutionEngine\Orc\ObjectLinkingLayerTest.cpp(115) : error C2065: 'TM' : undeclared identifier
FYI, "this->TM" was valid even before moving class SectionMemoryManagerWrapper.
llvm-svn: 257290
managers.
Prior to this patch, recursive finalization (where finalization of one
RuntimeDyld instance triggers finalization of another instance on which the
first depends) could trigger memory access failures: When the inner (dependent)
RuntimeDyld instance and its memory manager are finalized, memory allocated
(but not yet relocated) by the outer instance is locked, and relocation in the
outer instance fails with a memory access error.
This patch adds a latch to the RuntimeDyld::MemoryManager base class that is
checked by a new method: RuntimeDyld::finalizeWithMemoryManagerLocking, ensuring
that shared memory managers are only finalized by the outermost RuntimeDyld
instance.
This allows ORC clients to supply the same memory manager to multiple calls to
addModuleSet. In particular it enables the use of user-supplied memory managers
with the CompileOnDemandLayer which must reuse the supplied memory manager for
each function that is lazily compiled.
llvm-svn: 257263
