diff --git a/clang/include/clang/Basic/OpenCLExtensions.def b/clang/include/clang/Basic/OpenCLExtensions.def
--- a/clang/include/clang/Basic/OpenCLExtensions.def
+++ b/clang/include/clang/Basic/OpenCLExtensions.def
@@ -66,13 +66,6 @@
 OPENCLEXT_INTERNAL(cl_khr_mipmap_image_writes, 200, ~0U)
 OPENCLEXT_INTERNAL(cl_khr_srgb_image_writes, 200, ~0U)
 OPENCLEXT_INTERNAL(cl_khr_subgroups, 200, ~0U)
-OPENCLEXT_INTERNAL(cl_khr_subgroup_extended_types, 200, ~0U)
-OPENCLEXT_INTERNAL(cl_khr_subgroup_non_uniform_vote, 200, ~0U)
-OPENCLEXT_INTERNAL(cl_khr_subgroup_ballot, 200, ~0U)
-OPENCLEXT_INTERNAL(cl_khr_subgroup_non_uniform_arithmetic, 200, ~0U)
-OPENCLEXT_INTERNAL(cl_khr_subgroup_shuffle, 200, ~0U)
-OPENCLEXT_INTERNAL(cl_khr_subgroup_shuffle_relative, 200, ~0U)
-OPENCLEXT_INTERNAL(cl_khr_subgroup_clustered_reduce, 200, ~0U)
 
 // Clang Extensions.
 OPENCLEXT_INTERNAL(cl_clang_storage_class_specifiers, 100, ~0U)
diff --git a/clang/lib/Headers/opencl-c-base.h b/clang/lib/Headers/opencl-c-base.h
--- a/clang/lib/Headers/opencl-c-base.h
+++ b/clang/lib/Headers/opencl-c-base.h
@@ -9,6 +9,21 @@
 #ifndef _OPENCL_BASE_H_
 #define _OPENCL_BASE_H_
 
+// Define extension macros
+
+#if (defined(__OPENCL_CPP_VERSION__) || __OPENCL_C_VERSION__ >= 200)
+// For SPIR all extensions are supported.
+#if defined(__SPIR__)
+#define cl_khr_subgroup_extended_types 1
+#define cl_khr_subgroup_non_uniform_vote 1
+#define cl_khr_subgroup_ballot 1
+#define cl_khr_subgroup_non_uniform_arithmetic 1
+#define cl_khr_subgroup_shuffle 1
+#define cl_khr_subgroup_shuffle_relative 1
+#define cl_khr_subgroup_clustered_reduce 1
+#endif // defined(__SPIR__)
+#endif // (defined(__OPENCL_CPP_VERSION__) || __OPENCL_C_VERSION__ >= 200)
+
 // built-in scalar data types:
 
 /**
diff --git a/clang/test/Headers/opencl-c-header.cl b/clang/test/Headers/opencl-c-header.cl
--- a/clang/test/Headers/opencl-c-header.cl
+++ b/clang/test/Headers/opencl-c-header.cl
@@ -84,7 +84,11 @@
 #if defined(__OPENCL_CPP_VERSION__) || (__OPENCL_C_VERSION__ >= CL_VERSION_2_0)
 global atomic_int z = ATOMIC_VAR_INIT(99);
 #endif //__OPENCL_C_VERSION__
+// CHECK-MOD: Reading modules
+
+// Check that extension macros are defined correctly.
 
+// FIXME: this should not be defined for all targets
 // Verify that non-builtin cl_intel_planar_yuv extension is defined from
 // OpenCL 1.2 onwards.
 #if defined(__OPENCL_CPP_VERSION__) || (__OPENCL_C_VERSION__ >= CL_VERSION_1_2)
@@ -94,4 +98,57 @@
 #endif //__OPENCL_C_VERSION__
 #pragma OPENCL EXTENSION cl_intel_planar_yuv : enable
 
-// CHECK-MOD: Reading modules
+// For SPIR all extensions are supported.
+#if defined(__SPIR__)
+
+#if (defined(__OPENCL_CPP_VERSION__) || __OPENCL_C_VERSION__ >= 200)
+
+#if cl_khr_subgroup_extended_types != 1
+#error "Incorrectly defined cl_khr_subgroup_extended_types"
+#endif
+#if cl_khr_subgroup_non_uniform_vote != 1
+#error "Incorrectly defined cl_khr_subgroup_non_uniform_vote"
+#endif
+#if cl_khr_subgroup_ballot != 1
+#error "Incorrectly defined cl_khr_subgroup_ballot"
+#endif
+#if cl_khr_subgroup_non_uniform_arithmetic != 1
+#error "Incorrectly defined cl_khr_subgroup_non_uniform_arithmetic"
+#endif
+#if cl_khr_subgroup_shuffle != 1
+#error "Incorrectly defined cl_khr_subgroup_shuffle"
+#endif
+#if cl_khr_subgroup_shuffle_relative != 1
+#error "Incorrectly defined cl_khr_subgroup_shuffle_relative"
+#endif
+#if cl_khr_subgroup_clustered_reduce != 1
+#error "Incorrectly defined cl_khr_subgroup_clustered_reduce"
+#endif
+
+#else
+
+#ifdef cl_khr_subgroup_extended_types
+#error "Incorrect cl_khr_subgroup_extended_types define"
+#endif
+#ifdef cl_khr_subgroup_non_uniform_vote
+#error "Incorrect cl_khr_subgroup_non_uniform_vote define"
+#endif
+#ifdef cl_khr_subgroup_ballot
+#error "Incorrect cl_khr_subgroup_ballot define"
+#endif
+#ifdef cl_khr_subgroup_non_uniform_arithmetic
+#error "Incorrect cl_khr_subgroup_non_uniform_arithmetic define"
+#endif
+#ifdef cl_khr_subgroup_shuffle
+#error "Incorrect cl_khr_subgroup_shuffle define"
+#endif
+#ifdef cl_khr_subgroup_shuffle_relative
+#error "Incorrect cl_khr_subgroup_shuffle_relative define"
+#endif
+#ifdef cl_khr_subgroup_clustered_reduce
+#error "Incorrect cl_khr_subgroup_clustered_reduce define"
+#endif
+
+#endif //(defined(__OPENCL_CPP_VERSION__) || __OPENCL_C_VERSION__ >= 200)
+
+#endif // defined(__SPIR__)
diff --git a/clang/test/SemaOpenCL/extension-version.cl b/clang/test/SemaOpenCL/extension-version.cl
--- a/clang/test/SemaOpenCL/extension-version.cl
+++ b/clang/test/SemaOpenCL/extension-version.cl
@@ -205,88 +205,3 @@
 // expected-warning@+2{{unsupported OpenCL extension 'cl_intel_device_side_avc_motion_estimation' - ignoring}}
 #endif
 #pragma OPENCL EXTENSION cl_intel_device_side_avc_motion_estimation : enable
-
-#if (defined(__OPENCL_CPP_VERSION__) || __OPENCL_C_VERSION__ >= 200)
-#ifndef cl_khr_subgroup_extended_types
-#error "Missing cl_khr_subgroup_extended_types"
-#endif
-#else
-#ifdef cl_khr_subgroup_extended_types
-#error "Incorrect cl_khr_subgroup_extended_types define"
-#endif
-// expected-warning@+2{{unsupported OpenCL extension 'cl_khr_subgroup_extended_types' - ignoring}}
-#endif
-#pragma OPENCL EXTENSION cl_khr_subgroup_extended_types : enable
-
-#if (defined(__OPENCL_CPP_VERSION__) || __OPENCL_C_VERSION__ >= 200)
-#ifndef cl_khr_subgroup_non_uniform_vote
-#error "Missing cl_khr_subgroup_non_uniform_vote"
-#endif
-#else
-#ifdef cl_khr_subgroup_non_uniform_vote
-#error "Incorrect cl_khr_subgroup_non_uniform_vote define"
-#endif
-// expected-warning@+2{{unsupported OpenCL extension 'cl_khr_subgroup_non_uniform_vote' - ignoring}}
-#endif
-#pragma OPENCL EXTENSION cl_khr_subgroup_non_uniform_vote : enable
-
-#if (defined(__OPENCL_CPP_VERSION__) || __OPENCL_C_VERSION__ >= 200)
-#ifndef cl_khr_subgroup_ballot
-#error "Missing cl_khr_subgroup_ballot"
-#endif
-#else
-#ifdef cl_khr_subgroup_ballot
-#error "Incorrect cl_khr_subgroup_ballot define"
-#endif
-// expected-warning@+2{{unsupported OpenCL extension 'cl_khr_subgroup_ballot' - ignoring}}
-#endif
-#pragma OPENCL EXTENSION cl_khr_subgroup_ballot : enable
-
-#if (defined(__OPENCL_CPP_VERSION__) || __OPENCL_C_VERSION__ >= 200)
-#ifndef cl_khr_subgroup_non_uniform_arithmetic
-#error "Missing cl_khr_subgroup_non_uniform_arithmetic"
-#endif
-#else
-#ifdef cl_khr_subgroup_non_uniform_arithmetic
-#error "Incorrect cl_khr_subgroup_non_uniform_arithmetic define"
-#endif
-// expected-warning@+2{{unsupported OpenCL extension 'cl_khr_subgroup_non_uniform_arithmetic' - ignoring}}
-#endif
-#pragma OPENCL EXTENSION cl_khr_subgroup_non_uniform_arithmetic : enable
-
-#if (defined(__OPENCL_CPP_VERSION__) || __OPENCL_C_VERSION__ >= 200)
-#ifndef cl_khr_subgroup_shuffle
-#error "Missing cl_khr_subgroup_shuffle"
-#endif
-#else
-#ifdef cl_khr_subgroup_shuffle
-#error "Incorrect cl_khr_subgroup_shuffle define"
-#endif
-// expected-warning@+2{{unsupported OpenCL extension 'cl_khr_subgroup_shuffle' - ignoring}}
-#endif
-#pragma OPENCL EXTENSION cl_khr_subgroup_shuffle : enable
-
-#if (defined(__OPENCL_CPP_VERSION__) || __OPENCL_C_VERSION__ >= 200)
-#ifndef cl_khr_subgroup_shuffle_relative
-#error "Missing cl_khr_subgroup_shuffle_relative"
-#endif
-#else
-#ifdef cl_khr_subgroup_shuffle_relative
-#error "Incorrect cl_khr_subgroup_shuffle_relative define"
-#endif
-// expected-warning@+2{{unsupported OpenCL extension 'cl_khr_subgroup_shuffle_relative' - ignoring}}
-#endif
-#pragma OPENCL EXTENSION cl_khr_subgroup_shuffle_relative : enable
-
-#if (defined(__OPENCL_CPP_VERSION__) || __OPENCL_C_VERSION__ >= 200)
-#ifndef cl_khr_subgroup_clustered_reduce
-#error "Missing cl_khr_subgroup_clustered_reduce"
-#endif
-#else
-#ifdef cl_khr_subgroup_clustered_reduce
-#error "Incorrect cl_khr_subgroup_clustered_reduce define"
-#endif
-// expected-warning@+2{{unsupported OpenCL extension 'cl_khr_subgroup_clustered_reduce' - ignoring}}
-#endif
-#pragma OPENCL EXTENSION cl_khr_subgroup_clustered_reduce : enable
-