[lli] Test debug support in RuntimeDyld with built-in functions
When lli runs the below IR, it emits in-memory debug objects and registers them with the GDB JIT interface. The tests dump and check the registered information. IR has limited ability to produce complex output in a portable way. Instead the tests rely on built-in functions implemented in lli. They use a new command line flag `-generate=function-name` to instruct the ORC JIT to expose the built-in function with the given name to the JITed program.
`debug-descriptor-elf-minimal.ll` calls `__dump_jit_debug_descriptor()` to reflect the list of debug entries issued for itself after emitting the main module. The output is textual and can be checked straight away.
`debug-objects-elf-minimal.ll` calls `__dump_jit_debug_objects()`, which instructs lli to walk through the list of debug entries and append the encountered in-memory objects to the program output. We feed this output into llvm-dwarfdump to parse the DWARF in each file and dump their structures.
We can do the same for JITLink once D97335 has landed.
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D97694
GitOrigin-RevId: f47ff8cff1ede6ee017f4948f25a14e63de18612
diff --git a/tools/lli/ExecutionUtils.h b/tools/lli/ExecutionUtils.h
new file mode 100644
index 0000000..fcd1db0
--- /dev/null
+++ b/tools/lli/ExecutionUtils.h
@@ -0,0 +1,60 @@
+//===- ExecutionUtils.h - Utilities for executing code in lli ---*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// Contains utilities for executing code in lli.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_TOOLS_LLI_EXECUTIONUTILS_H
+#define LLVM_TOOLS_LLI_EXECUTIONUTILS_H
+
+#include "llvm/ExecutionEngine/JITSymbol.h"
+#include "llvm/ExecutionEngine/Orc/Core.h"
+#include "llvm/ExecutionEngine/Orc/Mangling.h"
+#include "llvm/Support/Error.h"
+#include "llvm/Support/ToolOutputFile.h"
+
+#include <memory>
+#include <utility>
+
+namespace llvm {
+
+enum class BuiltinFunctionKind {
+ DumpDebugDescriptor,
+ DumpDebugObjects,
+};
+
+// Utility class to expose symbols for special-purpose functions to the JIT.
+class LLIBuiltinFunctionGenerator : public orc::DefinitionGenerator {
+public:
+ LLIBuiltinFunctionGenerator(std::vector<BuiltinFunctionKind> Enabled,
+ orc::MangleAndInterner &Mangle);
+
+ Error tryToGenerate(orc::LookupState &LS, orc::LookupKind K,
+ orc::JITDylib &JD, orc::JITDylibLookupFlags JDLookupFlags,
+ const orc::SymbolLookupSet &Symbols) override;
+
+ void appendDebugObject(const char *Addr, size_t Size) {
+ TestOut->os().write(Addr, Size);
+ }
+
+private:
+ orc::SymbolMap BuiltinFunctions;
+ std::unique_ptr<ToolOutputFile> TestOut;
+
+ template <typename T> void expose(orc::SymbolStringPtr Name, T *Handler) {
+ BuiltinFunctions[Name] = JITEvaluatedSymbol(
+ pointerToJITTargetAddress(Handler), JITSymbolFlags::Exported);
+ }
+
+ static std::unique_ptr<ToolOutputFile> createToolOutput();
+};
+
+} // end namespace llvm
+
+#endif // LLVM_TOOLS_LLI_EXECUTIONUTILS_H