diff --git a/source/libgpuinfo.cpp b/source/libgpuinfo.cpp
index d1adae8..c695c44 100644
--- a/source/libgpuinfo.cpp
+++ b/source/libgpuinfo.cpp
@@ -852,6 +852,8 @@ class prop_decoder {
     bool decode(gpuinfo& info) {
         bool success = true;
 
+        // Zero init things we can read out-of-order
+        info.shader_core_mask = 0;
         uint64_t raw_gpu_id {};
         uint64_t raw_core_features {};
         uint64_t raw_thread_features {};
@@ -893,14 +895,19 @@ class prop_decoder {
                 assert(value == 1);
                 break;
             case prop_id_t::coherency_group_0:
-                info.num_shader_cores = __builtin_popcount(value);
-                info.shader_core_mask = value;
+            case prop_id_t::coherency_group_1:
+            case prop_id_t::coherency_group_2:
+            case prop_id_t::coherency_group_3:
+                info.shader_core_mask |= value;
                 break;
             default:
                 break;
             }
         }
 
+        // Accumulate this after all shader core bitmasks are merged
+        info.num_shader_cores = __builtin_popcount(info.shader_core_mask);
+
         // Decode architecture versions
         constexpr uint64_t bits4 { 0xF };
         constexpr uint64_t bits8 { 0xFF };