[Flang] Set address space during FIR pointer-like types lowering

This patch modifies FIR pointer-like types lowering to LLVM dialect to use the
address space stated in the module's data layout.

Author: skatrak

flang/include/flang/Optimizer/CodeGen/TypeConverter.h

@@ -101,7 +101,7 @@ class LLVMTypeConverter : public mlir::LLVMTypeConverter {
   }
 
   template <typename A> mlir::Type convertPointerLike(A &ty) const {
-    return mlir::LLVM::LLVMPointerType::get(ty.getContext());
+    return mlir::LLVM::LLVMPointerType::get(ty.getContext(), addressSpace);
   }
 
   // convert a front-end kind value to either a std or LLVM IR dialect type
@@ -127,6 +127,7 @@ class LLVMTypeConverter : public mlir::LLVMTypeConverter {
   KindMapping kindMapping;
   std::unique_ptr<CodeGenSpecifics> specifics;
   std::unique_ptr<TBAABuilder> tbaaBuilder;
+  unsigned addressSpace;
 };
 
 } // namespace fir

flang/lib/Optimizer/CodeGen/TypeConverter.cpp

@@ -35,7 +35,13 @@ LLVMTypeConverter::LLVMTypeConverter(mlir::ModuleOp module, bool applyTBAA,
                                       getTargetTriple(module),
                                       getKindMapping(module), dl)),
       tbaaBuilder(std::make_unique<TBAABuilder>(module->getContext(), applyTBAA,
-                                                forceUnifiedTBAATree)) {
+                                                forceUnifiedTBAATree)),
+      addressSpace(0) {
+  // Get default alloca address space for the current target
+  if (mlir::Attribute addrSpace =
+          mlir::DataLayout(module).getAllocaMemorySpace())
+    addressSpace = addrSpace.cast<mlir::IntegerAttr>().getUInt();
+
   LLVM_DEBUG(llvm::dbgs() << "FIR type converter\n");
 
   // Each conversion should return a value of type mlir::Type.

flang/test/Fir/alloca-addrspace-2.fir

@@ -0,0 +1,12 @@
+// RUN: fir-opt --fir-to-llvm-ir %s | FileCheck %s
+// RUN: tco --fir-to-llvm-ir %s | FileCheck %s
+
+module attributes { dlti.dl_spec = #dlti.dl_spec<#dlti.dl_entry<"dlti.alloca_memory_space", 5 : ui32>> } {
+  // CHECK-LABEL: llvm.func @set_addrspace
+  func.func @set_addrspace() {
+    // CHECK: llvm.alloca {{.*}} x i32
+    // CHECK-SAME: -> !llvm.ptr<i32, 5>
+    %0 = fir.alloca i32
+    return
+  }
+}

flang/test/Fir/alloca-addrspace.fir

@@ -0,0 +1,12 @@
+// RUN: fir-opt --fir-to-llvm-ir %s | FileCheck %s
+// RUN: tco --fir-to-llvm-ir %s | FileCheck %s
+
+module {
+  // CHECK-LABEL: llvm.func @default_addrspace
+  func.func @default_addrspace() {
+    // CHECK: llvm.alloca {{.*}} x i32
+    // CHECK-SAME: -> !llvm.ptr<i32>
+    %0 = fir.alloca i32
+    return
+  }
+}