[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

1 files changed, 2 insertions, 0 deletions

diff --git a/llvm/lib/ExecutionEngine/Orc/Legacy.cpp b/llvm/lib/ExecutionEngine/Orc/Legacy.cpp
index 795ddd582d8..79525baf92e 100644
--- a/llvm/lib/ExecutionEngine/Orc/Legacy.cpp
+++ b/llvm/lib/ExecutionEngine/Orc/Legacy.cpp
@@ -12,6 +12,8 @@
 namespace llvm {
 namespace orc {
 
+void SymbolResolver::anchor() {}
+
 JITSymbolResolverAdapter::JITSymbolResolverAdapter(
     ExecutionSession &ES, SymbolResolver &R, MaterializationResponsibility *MR)
     : ES(ES), R(R), MR(MR) {}