Fix printer for llvm.addressof symbol name that need escaping

[mehdi_amini]

Summary

Using printSymbolName() helper for printing symbol name will handle symbols
that require escaping/quoting.

[merge_guards_bot]

Unit tests: pass. 62028 tests passed, 0 failed and 783 were skipped.

clang-tidy: unknown.

clang-format: pass.

Build artifacts: diff.json, clang-format.patch, CMakeCache.txt, console-log.txt, test-results.xml

mlir/lib/Dialect/LLVMIR/IR/LLVMDialect.cpp

GlobalOp AddressOfOp::getGlobal() {
   while (module && !satisfiesLLVMModule(module))
     module = module->getParentOp();
   assert(module && "unexpected operation outside of a module");
   return dyn_cast_or_null<LLVM::GlobalOp>(
       mlir::SymbolTable::lookupSymbolIn(module, global_name()));
 }
 
 static void printAddressOfOp(OpAsmPrinter &p, AddressOfOp op) {
-  p << op.getOperationName() << " @" << op.global_name();
+  p << op.getOperationName() << " ";
+  p.printSymbolName(op.global_name());
   p.printOptionalAttrDict(op.getAttrs(), {"global_name"});
   p << " : " << op.getResult().getType();
 }
 
 static ParseResult parseAddressOfOp(OpAsmParser &parser,
                                     OperationState &result) {
   Attribute symRef;
   Type type;

mlir/test/Dialect/LLVMIR/global.mlir

 // RUN: mlir-opt -split-input-file -verify-diagnostics %s | FileCheck %s
 
 // CHECK: llvm.mlir.global internal @global(42 : i64) : !llvm.i64
 llvm.mlir.global internal @global(42 : i64) : !llvm.i64
 
 // CHECK: llvm.mlir.global internal constant @constant(3.700000e+01 : f64) : !llvm.float
 llvm.mlir.global internal constant @constant(37.0) : !llvm.float
 
-// CHECK: llvm.mlir.global internal constant @string("foobar")
-llvm.mlir.global internal constant @string("foobar") : !llvm<"[6 x i8]">
+// CHECK: llvm.mlir.global internal constant @".string"("foobar")
+llvm.mlir.global internal constant @".string"("foobar") : !llvm<"[6 x i8]">
 
 // CHECK: llvm.mlir.global internal @string_notype("1234567")
 llvm.mlir.global internal @string_notype("1234567")
 
 // CHECK: llvm.mlir.global internal @global_undef()
 llvm.mlir.global internal @global_undef() : !llvm.i64
 
 // CHECK: llvm.mlir.global internal @global_mega_initializer() : !llvm.i64 {

 // CHECK: llvm.mlir.global weak_odr
 llvm.mlir.global weak_odr @weak_odr() : !llvm.i64
 
 // CHECK-LABEL: references
 func @references() {
   // CHECK: llvm.mlir.addressof @global : !llvm<"i64*">
   %0 = llvm.mlir.addressof @global : !llvm<"i64*">
 
-  // CHECK: llvm.mlir.addressof @string : !llvm<"[6 x i8]*">
-  %1 = llvm.mlir.addressof @string : !llvm<"[6 x i8]*">
+  // CHECK: llvm.mlir.addressof @".string" : !llvm<"[6 x i8]*">
+  %1 = llvm.mlir.addressof @".string" : !llvm<"[6 x i8]*">
 
   llvm.return
 }
 
 // -----
 
 // expected-error @+1 {{op requires string attribute 'sym_name'}}
 "llvm.mlir.global"() {type = !llvm.i64, constant, value = 42 : i64} : () -> ()