From 247702e706f6019b204f2ea0b50c8843a7dc4cdd Mon Sep 17 00:00:00 2001
From: Gabriel Mitterrutzner <Gabriel.Mitterrutzner@student.uibk.ac.at>
Date: Mon, 27 Jan 2025 18:49:11 +0100
Subject: [PATCH] Change return type of 1D-element named swizzles

---
 include/simsycl/sycl/vec.hh | 12 ++++++------
 test/vec_tests.cc           | 15 +++++++++++++--
 2 files changed, 19 insertions(+), 8 deletions(-)

diff --git a/include/simsycl/sycl/vec.hh b/include/simsycl/sycl/vec.hh
index fcd2b6c..6ee8853 100644
--- a/include/simsycl/sycl/vec.hh
+++ b/include/simsycl/sycl/vec.hh
@@ -302,10 +302,10 @@ class swizzled_vec {
     }
 
 #define SIMSYCL_DETAIL_DEFINE_1D_SWIZZLE(req, comp)                                                                    \
-    auto comp() const                                                                                                  \
+    ReferenceDataT &comp() const                                                                                       \
         requires(req && num_elements > sycl::elem::comp)                                                               \
     {                                                                                                                  \
-        return detail::swizzled_vec<ReferenceDataT, indices[sycl::elem::comp]>(m_elems);                               \
+        return m_elems[indices[sycl::elem::comp]];                                                                     \
     }
 
 #define SIMSYCL_DETAIL_DEFINE_2D_SWIZZLE(req, comp1, comp2)                                                            \
@@ -612,15 +612,15 @@ class alignas(detail::vec_alignment_v<DataT, NumElements>) vec {
     }
 
 #define SIMSYCL_DETAIL_DEFINE_1D_SWIZZLE(req, comp)                                                                    \
-    auto comp()                                                                                                        \
+    DataT &comp()                                                                                                      \
         requires(req && num_elements > elem::comp)                                                                     \
     {                                                                                                                  \
-        return detail::swizzled_vec<DataT, elem::comp>(m_elems);                                                       \
+        return m_elems[elem::comp];                                                                                    \
     }                                                                                                                  \
-    auto comp() const                                                                                                  \
+    const DataT &comp() const                                                                                          \
         requires(req && num_elements > elem::comp)                                                                     \
     {                                                                                                                  \
-        return detail::swizzled_vec<const DataT, elem::comp>(m_elems);                                                 \
+        return m_elems[elem::comp];                                                                                    \
     }
 
 #define SIMSYCL_DETAIL_DEFINE_2D_SWIZZLE(req, comp1, comp2)                                                            \
diff --git a/test/vec_tests.cc b/test/vec_tests.cc
index 1a2f281..a2b4bfb 100644
--- a/test/vec_tests.cc
+++ b/test/vec_tests.cc
@@ -158,6 +158,17 @@ TEST_CASE("Vector swizzled access is available", "[vec][swizzle]") {
         vi.even() = {11, 12};
         CHECK(check_bool_vec(vi == sycl::vec<int, 4>{11, 9, 12, 10}));
     }
+
+    SECTION("1D swizzled vec return type") {
+        sycl::vec<uint8_t, 4> v4{255};
+        CHECK(std::is_same_v<decltype(v4.x()), uint8_t &>);
+        CHECK(std::is_same_v<decltype(v4.y()), uint8_t &>);
+        CHECK(std::is_same_v<decltype(v4.z()), uint8_t &>);
+        CHECK(std::is_same_v<decltype(v4.w()), uint8_t &>);
+
+        int i = (v4.x() + 1);
+        CHECK(i == 256);
+    }
 }
 
 TEST_CASE("Operations on swizzled vectors work as expected", "[vec][swizzle]") {
@@ -208,7 +219,7 @@ TEST_CASE("Operations on swizzled vectors work as expected", "[vec][swizzle]") {
         CHECK(check_bool_vec(sycl::vec<int, 2>{0, 0} < vi.xy()));
 
         CHECK(check_bool_vec(vi.zw() < 10));
-        CHECK(check_bool_vec(vi.z() == 3));
-        CHECK(check_bool_vec(4 == vi.a()));
+        CHECK((vi.z() == 3));
+        CHECK((4 == vi.a()));
     }
 }