add LLVM wrapper FFI

Author: xacrimon

compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp

@@ -51,6 +51,14 @@
 //
 //===----------------------------------------------------------------------===
 
+// Define TailCallKind enum values to match LLVM's
+enum LLVMRustTailCallKind {
+  LLVMRustTailCallKindNone = 0,
+  LLVMRustTailCallKindTail = 1,
+  LLVMRustTailCallKindMustTail = 2,
+  LLVMRustTailCallKindNoTail = 3
+};
+
 using namespace llvm;
 using namespace llvm::sys;
 using namespace llvm::object;
@@ -1949,3 +1957,21 @@ extern "C" void LLVMRustSetNoSanitizeHWAddress(LLVMValueRef Global) {
   MD.NoHWAddress = true;
   GV.setSanitizerMetadata(MD);
 }
+
+extern "C" void LLVMRustSetTailCallKind(LLVMValueRef Call, LLVMRustTailCallKind Kind) {
+  CallInst *CI = unwrap<CallInst>(Call);
+  switch (Kind) {
+    case LLVMRustTailCallKindNone:
+      CI->setTailCallKind(CallInst::TCK_None);
+      break;
+    case LLVMRustTailCallKindTail:
+      CI->setTailCallKind(CallInst::TCK_Tail);
+      break;
+    case LLVMRustTailCallKindMustTail:
+      CI->setTailCallKind(CallInst::TCK_MustTail);
+      break;
+    case LLVMRustTailCallKindNoTail:
+      CI->setTailCallKind(CallInst::TCK_NoTail);
+      break;
+  }
+}