Add 'BSLS_COMPILERFEATURES_SUPPORT_HARDWARE_INTERFERENCE' (2) (#5167)

* Add 'BSLS_COMPILERFEATURES_SUPPORT_HARDWARE_INTERFERENCE' (2)

* Forgot one file

groups/bsl/bsl+bslhdrs/bsl_new.h

@@ -62,9 +62,10 @@ namespace bsl {
 
 #ifdef BSLS_LIBRARYFEATURES_HAS_CPP17_BASELINE_LIBRARY
     using std::align_val_t;
-//  As of Apr-2022, no one (libc++, libstdc++, MSVC) has implemented these.
-//     using std::hardware_constructive_interference_size;
-//     using std::hardware_destructive_interference_size;
+# ifdef BSLS_COMPILERFEATURES_SUPPORT_HARDWARE_INTERFERENCE
+    using std::hardware_constructive_interference_size;
+    using std::hardware_destructive_interference_size;
+# endif // BSLS_COMPILERFEATURES_SUPPORT_HARDWARE_INTERFERENCE
     using std::launder;
 #endif  // BSLS_LIBRARYFEATURES_HAS_CPP17_BASELINE_LIBRARY
 

groups/bsl/bslim/bslim_bslstandardheadertest.t.cpp

@@ -952,6 +952,38 @@ int main(int argc, char *argv[])
     printf("TEST " __FILE__ " CASE %d\n", test);
 
     switch (test) { case 0:  // Zero is always the leading case.
+      case 39: {
+        // --------------------------------------------------------------------
+        // HARDWARE_INTERFERENCE
+        //
+        // Concerns:
+        // 1. The `bsl::hardware_constructive_interference_size` variable is
+        //    available in `bsl` to users who include `bsl_new.h`.
+        // 2. The `bsl::hardware_destructive_interference_size` variable is
+        //    available in `bsl` to users who include `bsl_new.h`.
+        //
+        // Plan:
+        // 1. Create a simple example that uses the variables.  Compilation of
+        //    the example demonstrates that the function can be found in `bsl`,
+        //    but only if BSLS_COMPILERFEATURES_SUPPORT_HARDWARE_INTERFERENCE
+        //    is defined.
+        //
+        // Testing
+        //   CONCERN: `hardware_constructive_interference_size` is in `bsl`.
+        //   CONCERN: `hardware_destructive_interference_size` is in `bsl`.
+        // --------------------------------------------------------------------
+        if (verbose) puts("\nHARDWARE_INTERFERENCE"
+                          "\n=====================");
+#if !defined(BSLS_COMPILERFEATURES_SUPPORT_HARDWARE_INTERFERENCE)
+        if (verbose) puts("\nHW Interference variables are not supported "
+                          "on this platform");
+#else
+        const size_t con = bsl::hardware_constructive_interference_size;
+        const size_t dis = bsl::hardware_destructive_interference_size;
+        (void) con;
+        (void) dis;
+#endif
+      } break;
       case 38: {
         // --------------------------------------------------------------------
         // `bsl::copy_n`

groups/bsl/bsls/bsls_compilerfeatures.h

@@ -1118,6 +1118,11 @@ BSLS_IDENT("$Id: $")
   #define BSLS_COMPILERFEATURES_SUPPORT_CONCEPTS                              1
 #endif
 
+#if defined(__cpp_lib_hardware_interference_size) &&                          \
+            __cpp_lib_hardware_interference_size >= 201703L
+  #define BSLS_COMPILERFEATURES_SUPPORT_HARDWARE_INTERFERENCE                 1
+#endif
+
 #if defined(__cpp_impl_three_way_comparison) &&                              \
                                     __cpp_impl_three_way_comparison >= 201907L
   #if defined(__cpp_lib_three_way_comparison) &&                             \

groups/bsl/bsls/bsls_compilerfeatures.t.cpp

@@ -26,6 +26,10 @@
     #include <type_traits>  // For testing only
 #endif
 
+#ifdef BSLS_COMPILERFEATURES_SUPPORT_HARDWARE_INTERFERENCE
+    #include <new>
+#endif
+
 //=============================================================================
 //                             TEST PLAN
 //-----------------------------------------------------------------------------
@@ -69,6 +73,7 @@
 // [ 8] BSLS_COMPILERFEATURES_SUPPORT_EXTERN_TEMPLATE
 // [ 9] BSLS_COMPILERFEATURES_SUPPORT_FINAL
 // [10] BSLS_COMPILERFEATURES_SUPPORT_GENERALIZED_INITIALIZERS
+// [41] BSLS_COMPILERFEATURES_SUPPORT_HARDWARE_INTERFERENCE
 // [23] BSLS_COMPILERFEATURES_SUPPORT_HAS_INCLUDE
 // [35] BSLS_COMPILERFEATURES_SUPPORT_HEXFLOAT_LITERALS
 // [11] BSLS_COMPILERFEATURES_SUPPORT_INCLUDE_NEXT
@@ -94,7 +99,7 @@
 // [  ] BSLS_COMPILERFEATURES_FORWARD_REF
 // [  ] BSLS_COMPILERFEATURES_FORWARD
 // ----------------------------------------------------------------------------
-// [41] USAGE EXAMPLE
+// [42] USAGE EXAMPLE
 
 #ifdef BDE_VERIFY
 // Suppress some pedantic bde_verify checks in this test driver
@@ -1914,6 +1919,13 @@ static void printFlags()
     puts("UNDEFINED");
 #endif
 
+    fputs("\n  BSLS_COMPILERFEATURES_SUPPORT_HARDWARE_INTERFERENCE: ", stdout);
+#ifdef BSLS_COMPILERFEATURES_SUPPORT_HARDWARE_INTERFERENCE
+    puts(STRINGIFY(BSLS_COMPILERFEATURES_SUPPORT_HARDWARE_INTERFERENCE));
+#else
+    puts("UNDEFINED");
+#endif
+
     puts("\n\n==printFlags: bsls_compilerfeatures Referenced Macros==");
 
     fputs("\n  BSLS_COMPILERFEATURES_SIMULATE_FORWARD_WORKAROUND: ", stdout);
@@ -2184,7 +2196,7 @@ int main(int argc, char *argv[])
     }
 
     switch (test) { case 0:
-      case 41: {
+      case 42: {
         // --------------------------------------------------------------------
         // USAGE EXAMPLE
         //
@@ -2265,6 +2277,37 @@ int main(int argc, char *argv[])
 // compilers) that further, more complicated or even indeterminate behaviors
 // may arise.
 #undef THATS_MY_LINE
+      } break;
+      case 41: {
+        // --------------------------------------------------------------------
+        // BSLS_COMPILERFEATURES_SUPPORT_HARDWARE_INTERFERENCE
+        //
+        // Concerns:
+        // 1. `BSLS_COMPILERFEATURES_SUPPORT_HARDWARE_INTERFERENCE` is defined
+        //    when the corresponding constants are defined.
+        //
+        // Plan:
+        // 1. Verify that the constants are defined when the macro is defined.
+        //
+        // Testing:
+        //   BSLS_COMPILERFEATURES_SUPPORT_HARDWARE_INTERFERENCE
+        // --------------------------------------------------------------------
+
+        MACRO_TEST_TITLE("_SUPPORT_HARDWARE_INTERFERENCE",
+                         "==============================");
+
+#ifndef BSLS_COMPILERFEATURES_SUPPORT_HARDWARE_INTERFERENCE
+        VERBOSE_PUTS("The feature is not supported in this configuration.");
+#else
+        ASSERT((std::is_same_v<
+                     const size_t, 
+                     decltype(std::hardware_destructive_interference_size)>));
+
+        ASSERT((std::is_same_v<
+                     const size_t, 
+                     decltype(std::hardware_constructive_interference_size)>));
+
+#endif  // BSLS_COMPILERFEATURES_SUPPORT_HARDWARE_INTERFERENCE
       } break;
       case 40: {
           // ------------------------------------------------------------------