Index: lib/Headers/ia32intrin.h
===================================================================
--- lib/Headers/ia32intrin.h
+++ lib/Headers/ia32intrin.h
@@ -55,6 +55,32 @@
 }
 #endif /* !__x86_64__ */
 
+static __inline__ unsigned int __attribute__((__always_inline__, __nodebug__, __target__("sse4.2")))
+__crc32b(unsigned int __C, unsigned char __D)
+{
+  return __builtin_ia32_crc32qi(__C, __D);
+}
+
+static __inline__ unsigned int __attribute__((__always_inline__, __nodebug__, __target__("sse4.2")))
+__crc32w(unsigned int __C, unsigned short __D)
+{
+  return __builtin_ia32_crc32hi(__C, __D);
+}
+
+static __inline__ unsigned int __attribute__((__always_inline__, __nodebug__, __target__("sse4.2")))
+__crc32d(unsigned int __C, unsigned int __D)
+{
+  return __builtin_ia32_crc32si(__C, __D);
+}
+
+#ifdef __x86_64__
+static __inline__ unsigned long long __attribute__((__always_inline__, __nodebug__, __target__("sse4.2")))
+__crc32q(unsigned long long __C, unsigned long long __D)
+{
+  return __builtin_ia32_crc32di(__C, __D);
+}
+#endif /* __x86_64__ */
+
 static __inline__ unsigned long long __attribute__((__always_inline__, __nodebug__))
 __rdpmc(int __A) {
   return __builtin_ia32_rdpmc(__A);
Index: test/CodeGen/x86-crc-builtins.c
===================================================================
--- /dev/null
+++ test/CodeGen/x86-crc-builtins.c
@@ -0,0 +1,30 @@
+// RUN: %clang_cc1 -ffreestanding %s -triple=x86_64-apple-darwin -target-feature +sse4.2 -emit-llvm -o - -Wall -Werror | FileCheck %s --check-prefixes=CHECK,CHECK64
+// RUN: %clang_cc1 -ffreestanding %s -triple=i686-apple-darwin -target-feature +sse4.2 -emit-llvm -o - -Wall -Werror | FileCheck %s
+
+#include <x86intrin.h>
+
+unsigned int test__crc32b(unsigned int CRC, unsigned char V) {
+// CHECK-LABEL: test__crc32b
+// CHECK: call i32 @llvm.x86.sse42.crc32.32.8(i32 %{{.*}}, i8 %{{.*}})
+  return __crc32b(CRC, V);
+}
+
+unsigned int test__crc32w(unsigned int CRC, unsigned short V) {
+// CHECK-LABEL: test__crc32w
+// CHECK: call i32 @llvm.x86.sse42.crc32.32.16(i32 %{{.*}}, i16 %{{.*}})
+  return __crc32w(CRC, V);
+}
+
+unsigned int test__crc32d(unsigned int CRC, unsigned int V) {
+// CHECK-LABEL: test__crc32d
+// CHECK: call i32 @llvm.x86.sse42.crc32.32.32(i32 %{{.*}}, i32 %{{.*}})
+  return __crc32d(CRC, V);
+}
+
+#ifdef __x86_64__
+unsigned long long test__crc32q(unsigned long long CRC, unsigned long long V) {
+// CHECK64-LABEL: test__crc32q
+// CHECK64: call i64 @llvm.x86.sse42.crc32.64.64(i64 %{{.*}}, i64 %{{.*}})
+  return __crc32q(CRC, V);
+}
+#endif