[SYCL] Cover more cases to compute kernel names length in compile time (#18804)

constexpr was added to detail::string_view to support this.

Author: Alexandr-Konovalov

sycl/include/sycl/detail/string_view.hpp

@@ -27,10 +27,10 @@ class string_view {
 #endif
 
 public:
-  string_view() noexcept = default;
-  string_view(const string_view &strn) noexcept = default;
-  string_view(string_view &&strn) noexcept = default;
-  string_view(std::string_view strn) noexcept
+  constexpr string_view() noexcept = default;
+  constexpr string_view(const string_view &strn) noexcept = default;
+  constexpr string_view(string_view &&strn) noexcept = default;
+  constexpr string_view(std::string_view strn) noexcept
       : str(strn.data())
 #ifdef __INTEL_PREVIEW_BREAKING_CHANGES
         ,
@@ -47,10 +47,10 @@ class string_view {
   {
   }
 
-  string_view &operator=(string_view &&strn) noexcept = default;
+  constexpr string_view &operator=(string_view &&strn) noexcept = default;
   string_view &operator=(const string_view &strn) noexcept = default;
 
-  string_view &operator=(std::string_view strn) noexcept {
+  constexpr string_view &operator=(std::string_view strn) noexcept {
     str = strn.data();
 #ifdef __INTEL_PREVIEW_BREAKING_CHANGES
     len = strn.size();
@@ -66,9 +66,9 @@ class string_view {
     return *this;
   }
 
-  const char *data() const noexcept { return str ? str : ""; }
+  constexpr const char *data() const noexcept { return str ? str : ""; }
 
-  explicit operator std::string_view() const noexcept {
+  constexpr explicit operator std::string_view() const noexcept {
 #ifdef __INTEL_PREVIEW_BREAKING_CHANGES
     return std::string_view(str, len);
 #else
@@ -77,31 +77,39 @@ class string_view {
   }
 
 #ifdef __INTEL_PREVIEW_BREAKING_CHANGES
-  friend bool operator==(string_view lhs, std::string_view rhs) noexcept {
+  friend constexpr bool operator==(string_view lhs,
+                                   std::string_view rhs) noexcept {
     return rhs == std::string_view(lhs);
   }
-  friend bool operator==(std::string_view lhs, string_view rhs) noexcept {
+  friend constexpr bool operator==(std::string_view lhs,
+                                   string_view rhs) noexcept {
     return lhs == std::string_view(rhs);
   }
 
-  friend bool operator!=(string_view lhs, std::string_view rhs) noexcept {
+  friend constexpr bool operator!=(string_view lhs,
+                                   std::string_view rhs) noexcept {
     return rhs != std::string_view(lhs);
   }
-  friend bool operator!=(std::string_view lhs, string_view rhs) noexcept {
+  friend constexpr bool operator!=(std::string_view lhs,
+                                   string_view rhs) noexcept {
     return lhs != std::string_view(rhs);
   }
 #else
-  friend bool operator==(string_view lhs, std::string_view rhs) noexcept {
+  friend constexpr bool operator==(string_view lhs,
+                                   std::string_view rhs) noexcept {
     return rhs == lhs.data();
   }
-  friend bool operator==(std::string_view lhs, string_view rhs) noexcept {
+  friend constexpr bool operator==(std::string_view lhs,
+                                   string_view rhs) noexcept {
     return lhs == rhs.data();
   }
 
-  friend bool operator!=(string_view lhs, std::string_view rhs) noexcept {
+  friend constexpr bool operator!=(string_view lhs,
+                                   std::string_view rhs) noexcept {
     return rhs != lhs.data();
   }
-  friend bool operator!=(std::string_view lhs, string_view rhs) noexcept {
+  friend constexpr bool operator!=(std::string_view lhs,
+                                   string_view rhs) noexcept {
     return lhs != rhs.data();
   }
 #endif

sycl/include/sycl/handler.hpp

@@ -1293,8 +1293,8 @@ class __SYCL_EXPORT handler {
       KernelWrapper<WrapAs::parallel_for, KName, decltype(Wrapper),
                     TransformedArgType, PropertiesT>::wrap(this, Wrapper);
 #ifndef __SYCL_DEVICE_ONLY__
-      verifyUsedKernelBundleInternal(
-          detail::string_view{detail::getKernelName<NameT>()});
+      constexpr detail::string_view Name{detail::getKernelName<NameT>()};
+      verifyUsedKernelBundleInternal(Name);
       // We are executing over the rounded range, but there are still
       // items/ids that are are constructed in ther range rounded
       // kernel use items/ids in the user range, which means that
@@ -1318,9 +1318,9 @@ class __SYCL_EXPORT handler {
       KernelWrapper<WrapAs::parallel_for, NameT, KernelType, TransformedArgType,
                     PropertiesT>::wrap(this, KernelFunc);
 #ifndef __SYCL_DEVICE_ONLY__
-      constexpr std::string_view Name{detail::getKernelName<NameT>()};
+      constexpr detail::string_view Name{detail::getKernelName<NameT>()};
 
-      verifyUsedKernelBundleInternal(detail::string_view{Name});
+      verifyUsedKernelBundleInternal(Name);
       processProperties<detail::isKernelESIMD<NameT>(), PropertiesT>(Props);
       detail::checkValueRange<Dims>(UserRange);
       setNDRangeDescriptor(std::move(UserRange));
@@ -1611,8 +1611,8 @@ class __SYCL_EXPORT handler {
       throwOnKernelParameterMisuse<KernelName, KernelType>();
     }
     throwIfActionIsCreated();
-    verifyUsedKernelBundleInternal(
-        detail::string_view{detail::getKernelName<NameT>()});
+    constexpr detail::string_view Name{detail::getKernelName<NameT>()};
+    verifyUsedKernelBundleInternal(Name);
     setType(detail::CGType::Kernel);
 
     detail::checkValueRange<Dims>(params...);
@@ -1655,8 +1655,8 @@ class __SYCL_EXPORT handler {
     // Ignore any set kernel bundles and use the one associated with the
     // kernel.
     setHandlerKernelBundle(Kernel);
-    verifyUsedKernelBundleInternal(
-        detail::string_view{detail::getKernelName<NameT>()});
+    constexpr detail::string_view Name{detail::getKernelName<NameT>()};
+    verifyUsedKernelBundleInternal(Name);
     setType(detail::CGType::Kernel);
 
     detail::checkValueRange<Dims>(params...);
@@ -2108,8 +2108,8 @@ class __SYCL_EXPORT handler {
     kernel_single_task<NameT>(KernelFunc);
 #ifndef __SYCL_DEVICE_ONLY__
     throwIfActionIsCreated();
-    verifyUsedKernelBundleInternal(
-        detail::string_view{detail::getKernelName<NameT>()});
+    constexpr detail::string_view Name{detail::getKernelName<NameT>()};
+    verifyUsedKernelBundleInternal(Name);
     // No need to check if range is out of INT_MAX limits as it's compile-time
     // known constant
     setNDRangeDescriptor(range<1>{1});