From 5e452ba204e322a21ab4321ac32de4e0a04bad0d Mon Sep 17 00:00:00 2001
From: HPS-1 <65581261+HPS-1@users.noreply.github.com>
Date: Fri, 26 Jan 2024 19:27:55 -0500
Subject: [PATCH] [SYCL] Modify detail::is_complex to handle cv qualifiers
 correctly (#12491)

Modify detail::is_complex to handle cv qualifiers correctly, by
replacing T with std::remove_cv_t\<T\> to strip off the cv qualifiers.
Its test cases have also been updated to check const and/or volatile
qualifers now. detail::is_plus and detail::is_multiplies are also
updated similarly to strip off const qualifers (as suggested by
@steffenlarsen, technically adding/removing volatile changes these two
types of operations, so volatile qualifers are not stripped off for
them).

---------

Signed-off-by: Hu, Peisen <peisen.hu@intel.com>
---
 sycl/include/sycl/group_algorithm.hpp         | 19 ++++++++++++-------
 sycl/include/sycl/stl_wrappers/complex        |  6 +++---
 .../Complex/sycl_complex_include_order.cpp    |  5 +++++
 3 files changed, 20 insertions(+), 10 deletions(-)

diff --git a/sycl/include/sycl/group_algorithm.hpp b/sycl/include/sycl/group_algorithm.hpp
index d22e3196e980..6f7f14feb6e3 100644
--- a/sycl/include/sycl/group_algorithm.hpp
+++ b/sycl/include/sycl/group_algorithm.hpp
@@ -116,14 +116,19 @@ template <typename T, typename BinaryOperation> struct is_native_op {
 // ---- is_plus
 template <typename T, typename BinaryOperation>
 using is_plus = std::integral_constant<
-    bool, std::is_same_v<BinaryOperation, sycl::plus<T>> ||
-              std::is_same_v<BinaryOperation, sycl::plus<void>>>;
+    bool,
+    std::is_same_v<BinaryOperation, sycl::plus<std::remove_const_t<T>>> ||
+        std::is_same_v<BinaryOperation, sycl::plus<std::add_const_t<T>>> ||
+        std::is_same_v<BinaryOperation, sycl::plus<void>>>;
 
 // ---- is_multiplies
 template <typename T, typename BinaryOperation>
 using is_multiplies = std::integral_constant<
-    bool, std::is_same_v<BinaryOperation, sycl::multiplies<T>> ||
-              std::is_same_v<BinaryOperation, sycl::multiplies<void>>>;
+    bool,
+    std::is_same_v<BinaryOperation, sycl::multiplies<std::remove_const_t<T>>> ||
+        std::is_same_v<BinaryOperation,
+                       sycl::multiplies<std::add_const_t<T>>> ||
+        std::is_same_v<BinaryOperation, sycl::multiplies<void>>>;
 
 // ---- is_complex
 // Use SFINAE so that the "true" branch could be implemented in
@@ -134,9 +139,9 @@ struct is_complex : public std::false_type {};
 
 // ---- is_arithmetic_or_complex
 template <typename T>
-using is_arithmetic_or_complex = std::integral_constant<
-    bool, sycl::detail::is_complex<typename std::remove_cv_t<T>>::value ||
-              sycl::detail::is_arithmetic<T>::value>;
+using is_arithmetic_or_complex =
+    std::integral_constant<bool, sycl::detail::is_complex<T>::value ||
+                                     sycl::detail::is_arithmetic<T>::value>;
 
 template <typename T>
 struct is_vector_arithmetic_or_complex
diff --git a/sycl/include/sycl/stl_wrappers/complex b/sycl/include/sycl/stl_wrappers/complex
index 6ed159eca7c5..281dac2aabde 100644
--- a/sycl/include/sycl/stl_wrappers/complex
+++ b/sycl/include/sycl/stl_wrappers/complex
@@ -93,9 +93,9 @@ struct isComplex<T, std::enable_if_t<std::is_same_v<T, std::complex<float>> ||
 
 // NOTE: std::complex<long double> not yet supported by group algorithms.
 template <typename T>
-struct is_complex<T, std::enable_if_t<std::is_same_v<T, std::complex<half>> ||
-                                      std::is_same_v<T, std::complex<float>> ||
-                                      std::is_same_v<T, std::complex<double>>>>
+struct is_complex<T, std::enable_if_t<std::is_same_v<std::remove_cv_t<T>, std::complex<half>> ||
+                                      std::is_same_v<std::remove_cv_t<T>, std::complex<float>> ||
+                                      std::is_same_v<std::remove_cv_t<T>, std::complex<double>>>>
     : public std::true_type {};
 
 #ifdef __SYCL_DEVICE_ONLY__
diff --git a/sycl/test-e2e/Complex/sycl_complex_include_order.cpp b/sycl/test-e2e/Complex/sycl_complex_include_order.cpp
index 69e6b0685c39..245d222c6520 100644
--- a/sycl/test-e2e/Complex/sycl_complex_include_order.cpp
+++ b/sycl/test-e2e/Complex/sycl_complex_include_order.cpp
@@ -31,6 +31,11 @@ int main() {
   queue q;
   auto test = []() {
     static_assert(sycl::detail::is_complex<std::complex<float>>::value);
+    static_assert(sycl::detail::is_complex<const std::complex<half>>::value);
+    static_assert(
+        sycl::detail::is_complex<const volatile std::complex<float>>::value);
+    static_assert(
+        sycl::detail::is_complex<volatile std::complex<double>>::value);
     static_assert(sycl::detail::isComplex<std::complex<float>>::value);
 #ifdef __SYCL_DEVICE_ONLY__
     static_assert(