1 files changed, 113 insertions, 0 deletions
diff --git a/src/backend/jit/llvm/llvmjit.c b/src/backend/jit/llvm/llvmjit.c
new file mode 100644
index 00000000000..9c579229153
--- /dev/null
+++ b/src/backend/jit/llvm/llvmjit.c
@@ -0,0 +1,113 @@
+/*-------------------------------------------------------------------------
+ *
+ * llvmjit.c
+ *	  Core part of the LLVM JIT provider.
+ *
+ * Copyright (c) 2016-2018, PostgreSQL Global Development Group
+ *
+ * IDENTIFICATION
+ *	  src/backend/jit/llvm/llvmjit.c
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "postgres.h"
+
+#include "jit/llvmjit.h"
+
+#include "miscadmin.h"
+
+#include "utils/memutils.h"
+#include "utils/resowner_private.h"
+#include "storage/ipc.h"
+
+
+#include <llvm-c/Target.h>
+
+
+static bool llvm_session_initialized = false;
+
+
+static void llvm_release_context(JitContext *context);
+static void llvm_session_initialize(void);
+static void llvm_shutdown(int code, Datum arg);
+
+
+PG_MODULE_MAGIC;
+
+
+/*
+ * Initialize LLVM JIT provider.
+ */
+void
+_PG_jit_provider_init(JitProviderCallbacks *cb)
+{
+	cb->reset_after_error = llvm_reset_after_error;
+	cb->release_context = llvm_release_context;
+}
+
+/*
+ * Create a context for JITing work.
+ *
+ * The context, including subsidiary resources, will be cleaned up either when
+ * the context is explicitly released, or when the lifetime of
+ * CurrentResourceOwner ends (usually the end of the current [sub]xact).
+ */
+LLVMJitContext *
+llvm_create_context(int jitFlags)
+{
+	LLVMJitContext *context;
+
+	llvm_assert_in_fatal_section();
+
+	llvm_session_initialize();
+
+	ResourceOwnerEnlargeJIT(CurrentResourceOwner);
+
+	context = MemoryContextAllocZero(TopMemoryContext,
+									 sizeof(LLVMJitContext));
+	context->base.flags = jitFlags;
+
+	/* ensure cleanup */
+	context->base.resowner = CurrentResourceOwner;
+	ResourceOwnerRememberJIT(CurrentResourceOwner, PointerGetDatum(context));
+
+	return context;
+}
+
+/*
+ * Release resources required by one llvm context.
+ */
+static void
+llvm_release_context(JitContext *context)
+{
+}
+
+/*
+ * Per session initialization.
+ */
+static void
+llvm_session_initialize(void)
+{
+	MemoryContext oldcontext;
+
+	if (llvm_session_initialized)
+		return;
+
+	oldcontext = MemoryContextSwitchTo(TopMemoryContext);
+
+	LLVMInitializeNativeTarget();
+	LLVMInitializeNativeAsmPrinter();
+	LLVMInitializeNativeAsmParser();
+
+	before_shmem_exit(llvm_shutdown, 0);
+
+	llvm_session_initialized = true;
+
+	MemoryContextSwitchTo(oldcontext);
+}
+
+static void
+llvm_shutdown(int code, Datum arg)
+{
+}