Implemented LLVMOrcCreateDynamicLibararySearchGeneratorForPath and LLVMOrcCreateStaticLibrarySearchGeneratorForPath for C -API.

[tpisto]

Summary

Implemented new functions for Orc V2 C-API:

LLVMOrcCreateDynamicLibararySearchGeneratorForPath
LLVMOrcCreateStaticLibrarySearchGeneratorForPath

Also created test cases for those and 2 test files.

[lhames]

Hi Tommi,

Thanks very much for working on these!

The pre-built archive and dylib are causing test failures on non-Darwin platforms. I haven't checked whether there's an easy way to build static and dynamic libraries from source for these tests. If there is then you should use that, but if not I'm ok with these APIs going in with an OrcV2Examples example and a TODO, rather than unit tests.

llvm/include/llvm-c/Orc.h

941–943

Could you add a note that this API is experimental, and likely to change in the near future?

(The basic concept is stable, but I think we might want to revisit how filters work to make them more efficient)

956–958

Could you also add a note that this API is experimental and subject to change?

We're in the process of tightening integration between ExecutionSession and ExecutorProcessControl. I think we can already look through the chain ObjLayer -> ExecutionSession -> ExecutorProcessControl to find the triple, but I'm not sure if that's set reliably in all cases. Once it is we will be able to drop the TargetTriple argument here.

[tpisto]

Removed unit tests and added experimental api warning.

[lhames]

LGTM. Thanks Tommi!

llvm/include/llvm-c/Orc.h

  * function is the full mangled symbol: The client is responsible for stripping
  * the global prefix if present.
  */
 LLVMErrorRef LLVMOrcCreateDynamicLibrarySearchGeneratorForProcess(
     LLVMOrcDefinitionGeneratorRef *Result, char GlobalPrefx,
     LLVMOrcSymbolPredicate Filter, void *FilterCtx);
 
 /**
+ * Get a LLVMOrcCreateDynamicLibararySearchGeneratorForPath that will reflect
+ * library symbols into the JITDylib. On success the resulting generator is
+ * owned by the client. Ownership is typically transferred by adding the
+ * instance to a JITDylib using LLVMOrcJITDylibAddGenerator,
+ *
+ * The GlobalPrefix argument specifies the character that appears on the front
+ * of linker-mangled symbols for the target platform (e.g. '_' on MachO).
+ * If non-null, this character will be stripped from the start of all symbol
+ * strings before passing the remaining substring to dlsym.
+ *
+ * The optional Filter and Ctx arguments can be used to supply a symbol name
+ * filter: Only symbols for which the filter returns true will be visible to
+ * JIT'd code. If the Filter argument is null then all library symbols will
+ * be visible to JIT'd code. Note that the symbol name passed to the Filter
+ * function is the full mangled symbol: The client is responsible for stripping
+ * the global prefix if present.
+ * 
+ * THIS API IS EXPERIMENTAL AND LIKELY TO CHANGE IN THE NEAR FUTURE!
+ * 
+ */
+LLVMErrorRef LLVMOrcCreateDynamicLibrarySearchGeneratorForPath(
+    LLVMOrcDefinitionGeneratorRef *Result, const char *FileName,
+    char GlobalPrefix, LLVMOrcSymbolPredicate Filter, void *FilterCtx);
+
+/**
+ * Get a LLVMOrcCreateStaticLibrarySearchGeneratorForPath that will reflect
+ * static library symbols into the JITDylib. On success the resulting
+ * generator is owned by the client. Ownership is typically transferred by
+ * adding the instance to a JITDylib using LLVMOrcJITDylibAddGenerator,
+ *
+ * Call with the optional TargetTriple argument will succeed if the file at
+ * the given path is a static library or a MachO universal binary containing a
+ * static library that is compatible with the given triple. Otherwise it will
+ * return an error.
+ *
+ * THIS API IS EXPERIMENTAL AND LIKELY TO CHANGE IN THE NEAR FUTURE!
+ * 
+ */
+LLVMErrorRef LLVMOrcCreateStaticLibrarySearchGeneratorForPath(
+    LLVMOrcDefinitionGeneratorRef *Result, LLVMOrcObjectLayerRef ObjLayer,
+    const char *FileName, const char *TargetTriple);
+
+/**
  * Create a ThreadSafeContext containing a new LLVMContext.
  *
  * Ownership of the underlying ThreadSafeContext data is shared: Clients
  * can and should dispose of their ThreadSafeContext as soon as they no longer
  * need to refer to it directly. Other references (e.g. from ThreadSafeModules)
  * will keep the data alive as long as it is needed.
  */
 LLVMOrcThreadSafeContextRef LLVMOrcCreateNewThreadSafeContext(void);

llvm/lib/ExecutionEngine/Orc/OrcV2CBindings.cpp

if (!ProcessSymsGenerator) {
     *Result = 0;
     return wrap(ProcessSymsGenerator.takeError());
   }
 
   *Result = wrap(ProcessSymsGenerator->release());
   return LLVMErrorSuccess;
 }
 
+LLVMErrorRef LLVMOrcCreateDynamicLibrarySearchGeneratorForPath(
+    LLVMOrcDefinitionGeneratorRef *Result, const char *FileName,
+    char GlobalPrefix, LLVMOrcSymbolPredicate Filter, void *FilterCtx) {
+  assert(Result && "Result can not be null");
+  assert(FileName && "FileName can not be null");
+  assert((Filter || !FilterCtx) &&
+         "if Filter is null then FilterCtx must also be null");
+
+  DynamicLibrarySearchGenerator::SymbolPredicate Pred;
+  if (Filter)
+    Pred = [=](const SymbolStringPtr &Name) -> bool {
+      return Filter(FilterCtx, wrap(OrcV2CAPIHelper::getRawPoolEntryPtr(Name)));
+    };
+
+  auto LibrarySymsGenerator =
+      DynamicLibrarySearchGenerator::Load(FileName, GlobalPrefix, Pred);
+
+  if (!LibrarySymsGenerator) {
+    *Result = 0;
+    return wrap(LibrarySymsGenerator.takeError());
+  }
+
+  *Result = wrap(LibrarySymsGenerator->release());
+  return LLVMErrorSuccess;
+}
+
+LLVMErrorRef LLVMOrcCreateStaticLibrarySearchGeneratorForPath(
+    LLVMOrcDefinitionGeneratorRef *Result, LLVMOrcObjectLayerRef ObjLayer,
+    const char *FileName, const char *TargetTriple) {
+  assert(Result && "Result can not be null");
+  assert(FileName && "Filename can not be null");
+  assert(ObjLayer && "ObjectLayer can not be null");
+
+  if (TargetTriple) {
+    auto TT = Triple(TargetTriple);
+    auto LibrarySymsGenerator =
+        StaticLibraryDefinitionGenerator::Load(*unwrap(ObjLayer), FileName, TT);
+    if (!LibrarySymsGenerator) {
+      *Result = 0;
+      return wrap(LibrarySymsGenerator.takeError());
+    }
+    *Result = wrap(LibrarySymsGenerator->release());
+    return LLVMErrorSuccess;
+  } else {
+    auto LibrarySymsGenerator =
+        StaticLibraryDefinitionGenerator::Load(*unwrap(ObjLayer), FileName);
+    if (!LibrarySymsGenerator) {
+      *Result = 0;
+      return wrap(LibrarySymsGenerator.takeError());
+    }
+    *Result = wrap(LibrarySymsGenerator->release());
+    return LLVMErrorSuccess;
+  }
+}
+
 LLVMOrcThreadSafeContextRef LLVMOrcCreateNewThreadSafeContext(void) {
   return wrap(new ThreadSafeContext(std::make_unique<LLVMContext>()));
 }
 
 LLVMContextRef
 LLVMOrcThreadSafeContextGetContext(LLVMOrcThreadSafeContextRef TSCtx) {
   return wrap(unwrap(TSCtx)->getContext());
 }