[mlir][llvmir] expose Type(To/From)LLVMIRTranslator C API (#124864)

mlir/include/mlir-c/Dialect/LLVM.h

@@ -52,6 +52,9 @@ MLIR_CAPI_EXPORTED intptr_t mlirLLVMFunctionTypeGetNumInputs(MlirType type);
 MLIR_CAPI_EXPORTED MlirType mlirLLVMFunctionTypeGetInput(MlirType type,
                                                          intptr_t pos);
 
+/// Returns the return type of the function type.
+MLIR_CAPI_EXPORTED MlirType mlirLLVMFunctionTypeGetReturnType(MlirType type);
+
 /// Returns `true` if the type is an LLVM dialect struct type.
 MLIR_CAPI_EXPORTED bool mlirTypeIsALLVMStructType(MlirType type);
 

mlir/include/mlir-c/Target/LLVMIR.h

@@ -16,6 +16,7 @@
 
 #include "mlir-c/IR.h"
 #include "mlir-c/Support.h"
+#include "llvm-c/Core.h"
 #include "llvm-c/Support.h"
 
 #ifdef __cplusplus
@@ -32,6 +33,48 @@ extern "C" {
 MLIR_CAPI_EXPORTED LLVMModuleRef
 mlirTranslateModuleToLLVMIR(MlirOperation module, LLVMContextRef context);
 
+struct MlirTypeFromLLVMIRTranslator {
+  void *ptr;
+};
+
+typedef struct MlirTypeFromLLVMIRTranslator MlirTypeFromLLVMIRTranslator;
+
+/// Create an LLVM::TypeFromLLVMIRTranslator and transfer ownership to the
+/// caller.
+MLIR_CAPI_EXPORTED MlirTypeFromLLVMIRTranslator
+mlirTypeFromLLVMIRTranslatorCreate(MlirContext ctx);
+
+/// Takes an LLVM::TypeFromLLVMIRTranslator owned by the caller and destroys it.
+/// It is the responsibility of the user to only pass an
+/// LLVM::TypeFromLLVMIRTranslator class.
+MLIR_CAPI_EXPORTED void
+mlirTypeFromLLVMIRTranslatorDestroy(MlirTypeFromLLVMIRTranslator translator);
+
+/// Translates the given LLVM IR type to the MLIR LLVM dialect.
+MLIR_CAPI_EXPORTED MlirType mlirTypeFromLLVMIRTranslatorTranslateType(
+    MlirTypeFromLLVMIRTranslator translator, LLVMTypeRef llvmType);
+
+struct MlirTypeToLLVMIRTranslator {
+  void *ptr;
+};
+
+typedef struct MlirTypeToLLVMIRTranslator MlirTypeToLLVMIRTranslator;
+
+/// Create an LLVM::TypeToLLVMIRTranslator and transfer ownership to the
+/// caller.
+MLIR_CAPI_EXPORTED MlirTypeToLLVMIRTranslator
+mlirTypeToLLVMIRTranslatorCreate(LLVMContextRef ctx);
+
+/// Takes an LLVM::TypeToLLVMIRTranslator owned by the caller and destroys it.
+/// It is the responsibility of the user to only pass an
+/// LLVM::TypeToLLVMIRTranslator class.
+MLIR_CAPI_EXPORTED void
+mlirTypeToLLVMIRTranslatorDestroy(MlirTypeToLLVMIRTranslator translator);
+
+/// Translates the given MLIR LLVM dialect to the LLVM IR type.
+MLIR_CAPI_EXPORTED LLVMTypeRef mlirTypeToLLVMIRTranslatorTranslateType(
+    MlirTypeToLLVMIRTranslator translator, MlirType mlirType);
+
 #ifdef __cplusplus
 }
 #endif

mlir/lib/CAPI/Dialect/LLVM.cpp

@@ -65,6 +65,10 @@ MlirType mlirLLVMFunctionTypeGetInput(MlirType type, intptr_t pos) {
                   .getParamType(static_cast<unsigned>(pos)));
 }
 
+MlirType mlirLLVMFunctionTypeGetReturnType(MlirType type) {
+  return wrap(llvm::cast<LLVM::LLVMFunctionType>(unwrap(type)).getReturnType());
+}
+
 bool mlirTypeIsALLVMStructType(MlirType type) {
   return isa<LLVM::LLVMStructType>(unwrap(type));
 }

mlir/lib/CAPI/Target/LLVMIR.cpp

@@ -8,16 +8,15 @@
 //===----------------------------------------------------------------------===//
 
 #include "mlir-c/Target/LLVMIR.h"
-#include "llvm-c/Support.h"
 
 #include "llvm/IR/LLVMContext.h"
 #include "llvm/IR/Module.h"
-#include <memory>
+#include "llvm/IR/Type.h"
 
 #include "mlir/CAPI/IR.h"
-#include "mlir/CAPI/Support.h"
 #include "mlir/CAPI/Wrap.h"
 #include "mlir/Target/LLVMIR/ModuleTranslation.h"
+#include "mlir/Target/LLVMIR/TypeFromLLVM.h"
 
 using namespace mlir;
 
@@ -34,3 +33,47 @@ LLVMModuleRef mlirTranslateModuleToLLVMIR(MlirOperation module,
 
   return moduleRef;
 }
+
+DEFINE_C_API_PTR_METHODS(MlirTypeFromLLVMIRTranslator,
+                         mlir::LLVM::TypeFromLLVMIRTranslator);
+
+MlirTypeFromLLVMIRTranslator
+mlirTypeFromLLVMIRTranslatorCreate(MlirContext ctx) {
+  MLIRContext *context = unwrap(ctx);
+  auto *translator = new LLVM::TypeFromLLVMIRTranslator(*context);
+  return wrap(translator);
+}
+
+void mlirTypeFromLLVMIRTranslatorDestroy(
+    MlirTypeFromLLVMIRTranslator translator) {
+  delete static_cast<LLVM::TypeFromLLVMIRTranslator *>(unwrap(translator));
+}
+
+MlirType mlirTypeFromLLVMIRTranslatorTranslateType(
+    MlirTypeFromLLVMIRTranslator translator, LLVMTypeRef llvmType) {
+  LLVM::TypeFromLLVMIRTranslator *translator_ = unwrap(translator);
+  mlir::Type type = translator_->translateType(llvm::unwrap(llvmType));
+  return wrap(type);
+}
+
+DEFINE_C_API_PTR_METHODS(MlirTypeToLLVMIRTranslator,
+                         mlir::LLVM::TypeToLLVMIRTranslator);
+
+MlirTypeToLLVMIRTranslator
+mlirTypeToLLVMIRTranslatorCreate(LLVMContextRef ctx) {
+  llvm::LLVMContext *context = llvm::unwrap(ctx);
+  auto *translator = new LLVM::TypeToLLVMIRTranslator(*context);
+  return wrap(translator);
+}
+
+void mlirTypeToLLVMIRTranslatorDestroy(MlirTypeToLLVMIRTranslator translator) {
+  delete static_cast<LLVM::TypeToLLVMIRTranslator *>(unwrap(translator));
+}
+
+LLVMTypeRef
+mlirTypeToLLVMIRTranslatorTranslateType(MlirTypeToLLVMIRTranslator translator,
+                                        MlirType mlirType) {
+  LLVM::TypeToLLVMIRTranslator *translator_ = unwrap(translator);
+  llvm::Type *type = translator_->translateType(unwrap(mlirType));
+  return llvm::wrap(type);
+}

mlir/test/CAPI/translation.c

@@ -58,11 +58,38 @@ static void testToLLVMIR(MlirContext ctx) {
   LLVMContextDispose(llvmCtx);
 }
 
+// CHECK-LABEL: testTypeToFromLLVMIRTranslator
+static void testTypeToFromLLVMIRTranslator(MlirContext ctx) {
+  fprintf(stderr, "testTypeToFromLLVMIRTranslator\n");
+  LLVMContextRef llvmCtx = LLVMContextCreate();
+
+  LLVMTypeRef llvmTy = LLVMInt32TypeInContext(llvmCtx);
+  MlirTypeFromLLVMIRTranslator fromLLVMTranslator =
+      mlirTypeFromLLVMIRTranslatorCreate(ctx);
+  MlirType mlirTy =
+      mlirTypeFromLLVMIRTranslatorTranslateType(fromLLVMTranslator, llvmTy);
+  // CHECK: i32
+  mlirTypeDump(mlirTy);
+
+  MlirTypeToLLVMIRTranslator toLLVMTranslator =
+      mlirTypeToLLVMIRTranslatorCreate(llvmCtx);
+  LLVMTypeRef llvmTy2 =
+      mlirTypeToLLVMIRTranslatorTranslateType(toLLVMTranslator, mlirTy);
+  // CHECK: i32
+  LLVMDumpType(llvmTy2);
+  fprintf(stderr, "\n");
+
+  mlirTypeFromLLVMIRTranslatorDestroy(fromLLVMTranslator);
+  mlirTypeToLLVMIRTranslatorDestroy(toLLVMTranslator);
+  LLVMContextDispose(llvmCtx);
+}
+
 int main(void) {
   MlirContext ctx = mlirContextCreate();
   mlirDialectHandleRegisterDialect(mlirGetDialectHandle__llvm__(), ctx);
   mlirContextGetOrLoadDialect(ctx, mlirStringRefCreateFromCString("llvm"));
   testToLLVMIR(ctx);
+  testTypeToFromLLVMIRTranslator(ctx);
   mlirContextDestroy(ctx);
   return 0;
 }