diff --git a/clang/include/clang/Basic/BuiltinsAMDGPU.def b/clang/include/clang/Basic/BuiltinsAMDGPU.def
--- a/clang/include/clang/Basic/BuiltinsAMDGPU.def
+++ b/clang/include/clang/Basic/BuiltinsAMDGPU.def
@@ -65,6 +65,7 @@
 BUILTIN(__builtin_amdgcn_ds_gws_sema_br, "vUiUi", "n")
 BUILTIN(__builtin_amdgcn_ds_gws_sema_p, "vUi", "n")
 BUILTIN(__builtin_amdgcn_fence, "vUicC*", "n")
+BUILTIN(__builtin_amdgcn_groupstaticsize, "Ui", "n")
 
 BUILTIN(__builtin_amdgcn_atomic_inc32, "UZiUZiD*UZiUicC*", "n")
 BUILTIN(__builtin_amdgcn_atomic_inc64, "UWiUWiD*UWiUicC*", "n")
diff --git a/clang/test/CodeGenOpenCL/builtins-amdgcn-ci.cl b/clang/test/CodeGenOpenCL/builtins-amdgcn-ci.cl
--- a/clang/test/CodeGenOpenCL/builtins-amdgcn-ci.cl
+++ b/clang/test/CodeGenOpenCL/builtins-amdgcn-ci.cl
@@ -62,3 +62,9 @@
 int test_is_private_global(const global int* ptr) {
   return __builtin_amdgcn_is_private(ptr);
 }
+
+// CHECK-LABEL: @test_groupstaticsize
+// CHECK: call i32 @llvm.amdgcn.groupstaticsize()
+void test_groupstaticsize(global uint* out) {
+  *out = __builtin_amdgcn_groupstaticsize();
+}
diff --git a/clang/test/CodeGenOpenCL/builtins-amdgcn-gfx10.cl b/clang/test/CodeGenOpenCL/builtins-amdgcn-gfx10.cl
--- a/clang/test/CodeGenOpenCL/builtins-amdgcn-gfx10.cl
+++ b/clang/test/CodeGenOpenCL/builtins-amdgcn-gfx10.cl
@@ -30,3 +30,10 @@
 {
   *out = __builtin_amdgcn_s_memtime();
 }
+
+// CHECK-LABEL: @test_groupstaticsize
+// CHECK: call i32 @llvm.amdgcn.groupstaticsize()
+void test_groupstaticsize(global uint* out)
+{
+  *out = __builtin_amdgcn_groupstaticsize();
+}
diff --git a/clang/test/CodeGenOpenCL/builtins-amdgcn-gfx9.cl b/clang/test/CodeGenOpenCL/builtins-amdgcn-gfx9.cl
--- a/clang/test/CodeGenOpenCL/builtins-amdgcn-gfx9.cl
+++ b/clang/test/CodeGenOpenCL/builtins-amdgcn-gfx9.cl
@@ -3,6 +3,7 @@
 // RUN: %clang_cc1 -triple amdgcn-unknown-unknown -target-cpu gfx1010 -S -emit-llvm -o - %s | FileCheck %s
 
 #pragma OPENCL EXTENSION cl_khr_fp16 : enable
+typedef unsigned int uint;
 typedef unsigned long ulong;
 
 // CHECK-LABEL: @test_fmed3_f16
@@ -18,3 +19,10 @@
 {
   *out = __builtin_amdgcn_s_memtime();
 }
+
+// CHECK-LABEL: @test_groupstaticsize
+// CHECK: call i32 @llvm.amdgcn.groupstaticsize()
+void test_groupstaticsize(global uint* out)
+{
+  *out = __builtin_amdgcn_groupstaticsize();
+}
diff --git a/clang/test/CodeGenOpenCL/builtins-amdgcn-vi.cl b/clang/test/CodeGenOpenCL/builtins-amdgcn-vi.cl
--- a/clang/test/CodeGenOpenCL/builtins-amdgcn-vi.cl
+++ b/clang/test/CodeGenOpenCL/builtins-amdgcn-vi.cl
@@ -145,3 +145,10 @@
 {
   *out = __builtin_amdgcn_perm(a, b, s);
 }
+
+// CHECK-LABEL: @test_groupstaticsize
+// CHECK: call i32 @llvm.amdgcn.groupstaticsize()
+void test_groupstaticsize(global uint* out)
+{
+  *out = __builtin_amdgcn_groupstaticsize();
+}