[mlir][llvm] Add LLVM_DependentLibrariesAttr (#133385)

https://llvm.org/docs/LangRef.html#dependent-libs-named-metadata

---------

Co-authored-by: Tobias Gysi <[email protected]>

Author: el-ev

mlir/include/mlir/Dialect/LLVMIR/LLVMAttrDefs.td

@@ -1327,4 +1327,23 @@ def ModuleFlagAttr
   let assemblyFormat = "`<` $behavior `,` $key `,` $value `>`";
 }
 
+//===----------------------------------------------------------------------===//
+// LLVM_DependentLibrariesAttr
+//===----------------------------------------------------------------------===//
+
+def LLVM_DependentLibrariesAttr
+    : LLVM_Attr<"DependentLibraries", "dependent_libraries"> {
+  let summary = "LLVM dependent libraries attribute";
+  let description = [{
+    Represents the list of dependent libraries for the current module.
+    This attribute is used to specify the libraries that the module depends
+    on, and it can be used for linking purposes.
+
+    See the following links for more details:
+    https://llvm.org/docs/LangRef.html#dependent-libs-named-metadata
+  }];
+  let parameters = (ins OptionalArrayRefParameter<"StringAttr">:$libs);
+  let assemblyFormat = "`<` $libs `>`";
+}
+
 #endif // LLVMIR_ATTRDEFS

mlir/include/mlir/Dialect/LLVMIR/LLVMDialect.td

@@ -83,6 +83,11 @@ def LLVM_Dialect : Dialect {
       return "llvm.emit_c_interface";
     }
 
+    /// Name of the dependent libraries attribute.
+    static StringRef getDependentLibrariesAttrName() {
+      return "llvm.dependent_libraries";
+    }
+
     /// Returns `true` if the given type is compatible with the LLVM dialect.
     static bool isCompatibleType(Type);
 

mlir/include/mlir/Target/LLVMIR/ModuleImport.h

@@ -229,6 +229,10 @@ class ModuleImport {
   /// attribute.
   LogicalResult convertCommandlineMetadata();
 
+  /// Converts !llvm.dependent-libraries metadata to llvm.dependent_libraries
+  /// LLVM ModuleOp attribute.
+  LogicalResult convertDependentLibrariesMetadata();
+
   /// Converts all LLVM metadata nodes that translate to attributes such as
   /// alias analysis or access group metadata, and builds a map from the
   /// metadata nodes to the converted attributes.

mlir/include/mlir/Target/LLVMIR/ModuleTranslation.h

@@ -363,6 +363,9 @@ class ModuleTranslation {
   /// Process the llvm.commandline LLVM Metadata, if it exists.
   LogicalResult createCommandlineMetadata();
 
+  /// Process the llvm.dependent_libraries LLVM Metadata, if it exists.
+  LogicalResult createDependentLibrariesMetadata();
+
   /// Translates dialect attributes attached to the given operation.
   LogicalResult
   convertDialectAttributes(Operation *op,

mlir/lib/Target/LLVMIR/ModuleImport.cpp

@@ -563,6 +563,23 @@ LogicalResult ModuleImport::convertLinkerOptionsMetadata() {
   return success();
 }
 
+LogicalResult ModuleImport::convertDependentLibrariesMetadata() {
+  for (const llvm::NamedMDNode &named : llvmModule->named_metadata()) {
+    if (named.getName() != "llvm.dependent-libraries")
+      continue;
+    SmallVector<StringRef> libraries;
+    for (const llvm::MDNode *node : named.operands()) {
+      if (node->getNumOperands() == 1)
+        if (auto *mdString = dyn_cast<llvm::MDString>(node->getOperand(0)))
+          libraries.push_back(mdString->getString());
+    }
+    if (!libraries.empty())
+      mlirModule->setAttr(LLVM::LLVMDialect::getDependentLibrariesAttrName(),
+                          builder.getStrArrayAttr(libraries));
+  }
+  return success();
+}
+
 LogicalResult ModuleImport::convertIdentMetadata() {
   for (const llvm::NamedMDNode &named : llvmModule->named_metadata()) {
     // llvm.ident should have a single operand. That operand is itself an
@@ -625,6 +642,8 @@ LogicalResult ModuleImport::convertMetadata() {
   }
   if (failed(convertLinkerOptionsMetadata()))
     return failure();
+  if (failed(convertDependentLibrariesMetadata()))
+    return failure();
   if (failed(convertModuleFlagsMetadata()))
     return failure();
   if (failed(convertIdentMetadata()))

mlir/lib/Target/LLVMIR/ModuleTranslation.cpp

@@ -2036,6 +2036,22 @@ LogicalResult ModuleTranslation::createCommandlineMetadata() {
   return success();
 }
 
+LogicalResult ModuleTranslation::createDependentLibrariesMetadata() {
+  if (auto dependentLibrariesAttr = mlirModule->getDiscardableAttr(
+          LLVM::LLVMDialect::getDependentLibrariesAttrName())) {
+    auto *nmd =
+        llvmModule->getOrInsertNamedMetadata("llvm.dependent-libraries");
+    llvm::LLVMContext &ctx = llvmModule->getContext();
+    for (auto libAttr :
+         cast<ArrayAttr>(dependentLibrariesAttr).getAsRange<StringAttr>()) {
+      auto *md =
+          llvm::MDNode::get(ctx, llvm::MDString::get(ctx, libAttr.getValue()));
+      nmd->addOperand(md);
+    }
+  }
+  return success();
+}
+
 void ModuleTranslation::setLoopMetadata(Operation *op,
                                         llvm::Instruction *inst) {
   LoopAnnotationAttr attr =
@@ -2201,6 +2217,8 @@ mlir::translateModuleToLLVMIR(Operation *module, llvm::LLVMContext &llvmContext,
     return nullptr;
   if (failed(translator.createCommandlineMetadata()))
     return nullptr;
+  if (failed(translator.createDependentLibrariesMetadata()))
+    return nullptr;
 
   // Convert other top-level operations if possible.
   for (Operation &o : getModuleBody(module).getOperations()) {

mlir/test/Target/LLVMIR/Import/metadata-dependent-libraries.ll

@@ -0,0 +1,6 @@
+; RUN: mlir-translate -import-llvm %s | FileCheck %s
+
+; CHECK: llvm.dependent_libraries = ["foo", "bar"]
+!llvm.dependent-libraries = !{!0, !1}
+!0 = !{!"foo"}
+!1 = !{!"bar"}

mlir/test/Target/LLVMIR/llvmir.mlir

@@ -2825,6 +2825,14 @@ module {
 
 // -----
 
+module attributes {llvm.dependent_libraries = ["foo", "bar"]} {}
+
+// CHECK: !llvm.dependent-libraries =  !{![[#LIBFOO:]], ![[#LIBBAR:]]}
+// CHECK: ![[#LIBFOO]] = !{!"foo"}
+// CHECK: ![[#LIBBAR]] = !{!"bar"}
+
+// -----
+
 llvm.mlir.global external constant @const() {addr_space = 0 : i32, dso_local} : i32 {
   %0 = llvm.mlir.addressof @const : !llvm.ptr
   %1 = llvm.ptrtoint %0 : !llvm.ptr to i64