diff --git a/clang/lib/Format/UnwrappedLineParser.cpp b/clang/lib/Format/UnwrappedLineParser.cpp
index c2cdc0695feb..951df79f91f6 100644
--- a/clang/lib/Format/UnwrappedLineParser.cpp
+++ b/clang/lib/Format/UnwrappedLineParser.cpp
@@ -1211,6 +1211,9 @@ void UnwrappedLineParser::parsePPDefine() {
     return;
   }
 
+#ifdef SYCLomatic_CUSTOMIZATION
+  bool MaybeIncludeGuard = false;
+#endif // SYCLomatic_CUSTOMIZATION
   if (IncludeGuard == IG_IfNdefed &&
       IncludeGuardToken->TokenText == FormatTok->TokenText) {
     IncludeGuard = IG_Defined;
@@ -1221,6 +1224,9 @@ void UnwrappedLineParser::parsePPDefine() {
         break;
       }
     }
+#ifdef SYCLomatic_CUSTOMIZATION
+    MaybeIncludeGuard = IncludeGuard == IG_Defined;
+#endif // SYCLomatic_CUSTOMIZATION
   }
 
   // In the context of a define, even keywords should be treated as normal
@@ -1231,6 +1237,13 @@ void UnwrappedLineParser::parsePPDefine() {
   FormatTok->Tok.setKind(tok::identifier);
   FormatTok->Tok.setIdentifierInfo(Keywords.kw_internal_ident_after_define);
   nextToken();
+
+#ifdef SYCLomatic_CUSTOMIZATION
+  // IncludeGuard can't have a non-empty macro definition.
+  if (MaybeIncludeGuard && !eof())
+    IncludeGuard = IG_Rejected;
+#endif // SYCLomatic_CUSTOMIZATION
+
   if (FormatTok->Tok.getKind() == tok::l_paren &&
       !FormatTok->hasWhitespaceBefore()) {
     parseParens();
diff --git a/clang/test/dpct/format/.clang-format b/clang/test/dpct/format/.clang-format
new file mode 100644
index 000000000000..5d5bb0d22dcb
--- /dev/null
+++ b/clang/test/dpct/format/.clang-format
@@ -0,0 +1 @@
+IndentPPDirectives: BeforeHash
diff --git a/clang/test/dpct/format/BeforeHash.cu b/clang/test/dpct/format/BeforeHash.cu
new file mode 100644
index 000000000000..bae448b5af68
--- /dev/null
+++ b/clang/test/dpct/format/BeforeHash.cu
@@ -0,0 +1,23 @@
+// RUN: cd %S
+// RUN: dpct --out-root %T %s --cuda-include-path="%cuda-path/include"
+// RUN: FileCheck %s --match-full-lines --input-file %T/BeforeHash.dp.cpp
+// RUN: %if build_lit %{icpx -c -fsycl %T/BeforeHash.dp.cpp -o %T/BeforeHash.dp.o %}
+
+#ifndef ABCD
+#define ABCD 0
+#endif
+
+// CHECK: #define DPCT_PROFILING_ENABLED
+// CHECK-NEXT: #include <sycl/sycl.hpp>
+// CHECK-NEXT: #include <dpct/dpct.hpp>
+// CHECK-NEXT: #include <cstdio>
+#include <cstdio>
+
+// CHECK: void foo() {
+// CHECK-NEXT:   dpct::event_ptr start;
+// CHECK-NEXT:   dpct::sync_barrier(start);
+// CHECK-NEXT: }
+void foo() {
+  cudaEvent_t start;
+  cudaEventRecord(start);
+}