[Orc] Add basic OrcV2 C bindings and example.

Renames the llvm/examples/LLJITExamples directory to llvm/examples/OrcV2Examples
since it is becoming a home for all OrcV2 examples, not just LLJIT.

See http://llvm.org/PR31103.

examples/CMakeLists.txt

@@ -3,9 +3,9 @@ add_subdirectory(Fibonacci)
 add_subdirectory(HowToUseJIT)
 add_subdirectory(HowToUseLLJIT)
 add_subdirectory(IRTransforms)
-add_subdirectory(LLJITExamples)
 add_subdirectory(Kaleidoscope)
 add_subdirectory(ModuleMaker)
+add_subdirectory(OrcV2Examples)
 add_subdirectory(SpeculativeJIT)
 add_subdirectory(Bye)
 add_subdirectory(ThinLtoJIT)

examples/OrcV2Examples/BasicOrcV2CBindings/BasicOrcV2CBindings.c

@@ -0,0 +1,142 @@
+//===-------- BasicOrcV2CBindings.c - Basic OrcV2 C Bindings Demo ---------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm-c/Core.h"
+#include "llvm-c/Error.h"
+#include "llvm-c/Initialization.h"
+#include "llvm-c/Orc.h"
+#include "llvm-c/Support.h"
+#include "llvm-c/Target.h"
+
+#include <stdio.h>
+
+int handleError(LLVMErrorRef Err) {
+  char *ErrMsg = LLVMGetErrorMessage(Err);
+  fprintf(stderr, "Error: %s\n", ErrMsg);
+  LLVMDisposeErrorMessage(ErrMsg);
+  return 1;
+}
+
+LLVMOrcThreadSafeModuleRef createDemoModule() {
+  // Create a new ThreadSafeContext and underlying LLVMContext.
+  LLVMOrcThreadSafeContextRef TSCtx = LLVMOrcCreateNewThreadSafeContext();
+
+  // Get a reference to the underlying LLVMContext.
+  LLVMContextRef Ctx = LLVMOrcThreadSafeContextGetContext(TSCtx);
+
+  // Create a new LLVM module.
+  LLVMModuleRef M = LLVMModuleCreateWithNameInContext("demo", Ctx);
+
+  // Add a "sum" function":
+  //  - Create the function type and function instance.
+  LLVMTypeRef ParamTypes[] = {LLVMInt32Type(), LLVMInt32Type()};
+  LLVMTypeRef SumFunctionType =
+      LLVMFunctionType(LLVMInt32Type(), ParamTypes, 2, 0);
+  LLVMValueRef SumFunction = LLVMAddFunction(M, "sum", SumFunctionType);
+
+  //  - Add a basic block to the function.
+  LLVMBasicBlockRef EntryBB = LLVMAppendBasicBlock(SumFunction, "entry");
+
+  //  - Add an IR builder and point it at the end of the basic block.
+  LLVMBuilderRef Builder = LLVMCreateBuilder();
+  LLVMPositionBuilderAtEnd(Builder, EntryBB);
+
+  //  - Get the two function arguments and use them co construct an "add"
+  //    instruction.
+  LLVMValueRef SumArg0 = LLVMGetParam(SumFunction, 0);
+  LLVMValueRef SumArg1 = LLVMGetParam(SumFunction, 1);
+  LLVMValueRef Result = LLVMBuildAdd(Builder, SumArg0, SumArg1, "result");
+
+  //  - Build the return instruction.
+  LLVMBuildRet(Builder, Result);
+
+  // Our demo module is now complete. Wrap it and our ThreadSafeContext in a
+  // ThreadSafeModule.
+  LLVMOrcThreadSafeModuleRef TSM = LLVMOrcCreateNewThreadSafeModule(M, TSCtx);
+
+  // Dispose of our local ThreadSafeContext value. The underlying LLVMContext
+  // will be kept alive by our ThreadSafeModule, TSM.
+  LLVMOrcDisposeThreadSafeContext(TSCtx);
+
+  // Return the result.
+  return TSM;
+}
+
+int main(int argc, char *argv[]) {
+
+  int MainResult = 0;
+
+  // Parse command line arguments and initialize LLVM Core.
+  LLVMParseCommandLineOptions(argc, (const char **)argv, "");
+  LLVMInitializeCore(LLVMGetGlobalPassRegistry());
+
+  // Initialize native target codegen and asm printer.
+  LLVMInitializeNativeTarget();
+  LLVMInitializeNativeAsmPrinter();
+
+  // Create the JIT instance.
+  LLVMOrcLLJITRef J;
+  {
+    LLVMErrorRef Err;
+    if ((Err = LLVMOrcCreateDefaultLLJIT(&J))) {
+      MainResult = handleError(Err);
+      goto llvm_shutdown;
+    }
+  }
+
+  // Create our demo module.
+  LLVMOrcThreadSafeModuleRef TSM = createDemoModule();
+
+  // Add our demo module to the JIT.
+  {
+    LLVMErrorRef Err;
+    if ((Err = LLVMOrcLLJITAddLLVMIRModule(J, TSM))) {
+      // If adding the ThreadSafeModule fails then we need to clean it up
+      // ourselves. If adding it succeeds the JIT will manage the memory.
+      LLVMOrcDisposeThreadSafeModule(TSM);
+      MainResult = handleError(Err);
+      goto jit_cleanup;
+    }
+  }
+
+  // Look up the address of our demo entry point.
+  LLVMOrcJITTargetAddress SumAddr;
+  {
+    LLVMErrorRef Err;
+    if ((Err = LLVMOrcLLJITLookup(J, &SumAddr, "sum"))) {
+      MainResult = handleError(Err);
+      goto jit_cleanup;
+    }
+  }
+
+  // If we made it here then everything succeeded. Execute our JIT'd code.
+  int32_t (*Sum)(int32_t, int32_t) = (int32_t(*)(int32_t, int32_t))SumAddr;
+  int32_t Result = Sum(1, 2);
+
+  // Print the result.
+  printf("1 + 2 = %i\n", Result);
+
+jit_cleanup:
+  // Destroy our JIT instance. This will clean up any memory that the JIT has
+  // taken ownership of. This operation is non-trivial (e.g. it may need to
+  // JIT static destructors) and may also fail. In that case we want to render
+  // the error to stderr, but not overwrite any existing return value.
+  {
+    LLVMErrorRef Err;
+    if ((Err = LLVMOrcDisposeLLJIT(J))) {
+      int NewFailureResult = handleError(Err);
+      if (MainResult == 0)
+        MainResult = NewFailureResult;
+    }
+  }
+
+llvm_shutdown:
+  // Shut down LLVM.
+  LLVMShutdown();
+  return 0;
+}

examples/OrcV2Examples/BasicOrcV2CBindings/CMakeLists.txt

@@ -0,0 +1,15 @@
+set(LLVM_LINK_COMPONENTS
+  Core
+  ExecutionEngine
+  IRReader
+  JITLink
+  MC
+  OrcJIT
+  Support
+  Target
+  nativecodegen
+  )
+
+add_llvm_example(BasicOrcV2CBindings
+  BasicOrcV2CBindings.c
+  )

examples/OrcV2Examples/CMakeLists.txt

@@ -1,3 +1,4 @@
+add_subdirectory(BasicOrcV2CBindings)
 add_subdirectory(LLJITDumpObjects)
 add_subdirectory(LLJITWithObjectCache)
 add_subdirectory(LLJITWithCustomObjectLinkingLayer)

include/llvm-c/Orc.h

@@ -0,0 +1,95 @@
+/*===---------------- llvm-c/Orc.h - OrcV2 C bindings -----------*- 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                    *|
+|*                                                                            *|
+|*===----------------------------------------------------------------------===*|
+|*                                                                            *|
+|* This header declares the C interface to libLLVMOrcJIT.a, which implements  *|
+|* JIT compilation of LLVM IR.                                                *|
+|*                                                                            *|
+|* Many exotic languages can interoperate with C code but have a harder time  *|
+|* with C++ due to name mangling. So in addition to C, this interface enables *|
+|* tools written in such languages.                                           *|
+|*                                                                            *|
+|* Note: This interface is experimental. It is *NOT* stable, and may be       *|
+|*       changed without warning. Only C API usage documentation is           *|
+|*       provided. See the C++ documentation for all higher level ORC API     *|
+|*       details.                                                             *|
+|*                                                                            *|
+\*===----------------------------------------------------------------------===*/
+
+#ifndef LLVM_C_ORC_H
+#define LLVM_C_ORC_H
+
+#include "llvm-c/Error.h"
+#include "llvm-c/Types.h"
+
+LLVM_C_EXTERN_C_BEGIN
+
+typedef struct LLVMOrcOpaqueThreadSafeContext *LLVMOrcThreadSafeContextRef;
+typedef struct LLVMOrcOpaqueThreadSafeModule *LLVMOrcThreadSafeModuleRef;
+typedef struct LLVMOrcOpaqueLLJIT *LLVMOrcLLJITRef;
+typedef uint64_t LLVMOrcJITTargetAddress;
+
+/**
+ * Create a ThreadSafeContext containing a new LLVMContext.
+ */
+LLVMOrcThreadSafeContextRef LLVMOrcCreateNewThreadSafeContext(void);
+
+/**
+ * Get a reference to the wrapped LLVMContext.
+ */
+LLVMContextRef
+LLVMOrcThreadSafeContextGetContext(LLVMOrcThreadSafeContextRef TSCtx);
+
+/**
+ * Dispose of a ThreadSafeContext.
+ */
+void LLVMOrcDisposeThreadSafeContext(LLVMOrcThreadSafeContextRef TSCtx);
+
+/**
+ * Create a ThreadSafeModule wrapper around the given LLVM module. This takes
+ * ownership of the M argument which should not be disposed of or referenced
+ * after this function returns.
+ */
+LLVMOrcThreadSafeModuleRef
+LLVMOrcCreateNewThreadSafeModule(LLVMModuleRef M,
+                                 LLVMOrcThreadSafeContextRef TSCtx);
+
+/**
+ * Dispose of a ThreadSafeModule.
+ */
+void LLVMOrcDisposeThreadSafeModule(LLVMOrcThreadSafeModuleRef TSM);
+
+/**
+ * Create an LLJIT instance using all default values.
+ */
+LLVMErrorRef LLVMOrcCreateDefaultLLJIT(LLVMOrcLLJITRef *Result);
+
+/**
+ * Dispose of an LLJIT instance.
+ */
+LLVMErrorRef LLVMOrcDisposeLLJIT(LLVMOrcLLJITRef J);
+
+/**
+ * Add an IR module to the main JITDylib of the given LLJIT instance. This
+ * operation takes ownership of the TSM argument which should not be disposed
+ * of or referenced once this function returns.
+ */
+LLVMErrorRef LLVMOrcLLJITAddLLVMIRModule(LLVMOrcLLJITRef J,
+                                         LLVMOrcThreadSafeModuleRef TSM);
+/**
+ * Look up the given symbol in the main JITDylib of the given LLJIT instance.
+ *
+ * This operation does not take ownership of the Name argument.
+ */
+LLVMErrorRef LLVMOrcLLJITLookup(LLVMOrcLLJITRef J,
+                                LLVMOrcJITTargetAddress *Result,
+                                const char *Name);
+
+LLVM_C_EXTERN_C_END
+
+#endif /* LLVM_C_ORC_H */

lib/ExecutionEngine/Orc/CMakeLists.txt

@@ -19,6 +19,7 @@ add_llvm_component_library(LLVMOrcJIT
   ObjectTransformLayer.cpp
   OrcABISupport.cpp
   OrcCBindings.cpp
+  OrcV2CBindings.cpp
   OrcMCJITReplacement.cpp
   RTDyldObjectLinkingLayer.cpp
   ThreadSafeModule.cpp

lib/ExecutionEngine/Orc/OrcV2CBindings.cpp

@@ -0,0 +1,80 @@
+//===--------------- OrcV2CBindings.cpp - C bindings OrcV2 APIs -----------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm-c/Orc.h"
+#include "llvm-c/TargetMachine.h"
+
+#include "llvm/ExecutionEngine/Orc/JITTargetMachineBuilder.h"
+#include "llvm/ExecutionEngine/Orc/LLJIT.h"
+
+using namespace llvm;
+using namespace llvm::orc;
+
+DEFINE_SIMPLE_CONVERSION_FUNCTIONS(ThreadSafeContext,
+                                   LLVMOrcThreadSafeContextRef)
+DEFINE_SIMPLE_CONVERSION_FUNCTIONS(ThreadSafeModule, LLVMOrcThreadSafeModuleRef)
+DEFINE_SIMPLE_CONVERSION_FUNCTIONS(LLJIT, LLVMOrcLLJITRef)
+
+LLVMOrcThreadSafeContextRef LLVMOrcCreateNewThreadSafeContext() {
+  return wrap(new ThreadSafeContext(std::make_unique<LLVMContext>()));
+}
+
+LLVMContextRef
+LLVMOrcThreadSafeContextGetContext(LLVMOrcThreadSafeContextRef TSCtx) {
+  return wrap(unwrap(TSCtx)->getContext());
+}
+
+void LLVMOrcDisposeThreadSafeContext(LLVMOrcThreadSafeContextRef TSCtx) {
+  delete unwrap(TSCtx);
+}
+
+LLVMOrcThreadSafeModuleRef
+LLVMOrcCreateNewThreadSafeModule(LLVMModuleRef M,
+                                 LLVMOrcThreadSafeContextRef TSCtx) {
+  return wrap(
+      new ThreadSafeModule(std::unique_ptr<Module>(unwrap(M)), *unwrap(TSCtx)));
+}
+
+void LLVMOrcDisposeThreadSafeModule(LLVMOrcThreadSafeModuleRef TSM) {
+  delete unwrap(TSM);
+}
+
+LLVMErrorRef LLVMOrcCreateDefaultLLJIT(LLVMOrcLLJITRef *Result) {
+  auto J = LLJITBuilder().create();
+
+  if (!J) {
+    Result = 0;
+    return wrap(J.takeError());
+  }
+
+  *Result = wrap(J->release());
+  return LLVMErrorSuccess;
+}
+
+LLVMErrorRef LLVMOrcDisposeLLJIT(LLVMOrcLLJITRef J) {
+  delete unwrap(J);
+  return LLVMErrorSuccess;
+}
+
+LLVMErrorRef LLVMOrcLLJITAddLLVMIRModule(LLVMOrcLLJITRef J,
+                                         LLVMOrcThreadSafeModuleRef TSM) {
+  return wrap(unwrap(J)->addIRModule(std::move(*unwrap(TSM))));
+}
+
+LLVMErrorRef LLVMOrcLLJITLookup(LLVMOrcLLJITRef J,
+                                LLVMOrcJITTargetAddress *Result,
+                                const char *Name) {
+  auto Sym = unwrap(J)->lookup(Name);
+  if (!Sym) {
+    *Result = 0;
+    return wrap(Sym.takeError());
+  }
+
+  *Result = Sym->getAddress();
+  return LLVMErrorSuccess;
+}