[SYCL] Support __builtin_printf for SYCL device

clang/lib/Sema/SemaSYCL.cpp

@@ -368,9 +368,11 @@ bool Sema::isDeclAllowedInSYCLDeviceCode(const Decl *D) {
   if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
     const IdentifierInfo *II = FD->getIdentifier();
 
-    // Allow __builtin_assume_aligned to be called from within device code.
+    // Allow __builtin_assume_aligned and __builtin_printf to be called from
+    // within device code.
     if (FD->getBuiltinID() &&
-        FD->getBuiltinID() == Builtin::BI__builtin_assume_aligned)
+        (FD->getBuiltinID() == Builtin::BI__builtin_assume_aligned ||
+         FD->getBuiltinID() == Builtin::BI__builtin_printf))
       return true;
 
     // Allow to use `::printf` only for CUDA.

clang/test/CodeGenSYCL/remove-restriction-builtin-printf.cpp

@@ -0,0 +1,18 @@
+// RUN: %clang_cc1 -fsycl-is-device -internal-isystem %S/Inputs -sycl-std=2020 -emit-llvm %s -o - | FileCheck %s
+// This test checks if __builtin_printf is emitted in the IR.
+
+#include "sycl.hpp"
+
+using namespace sycl;
+queue q;
+
+int main() {
+  q.submit([&](handler &h) {
+    // CHECK: define {{.*}}spir_kernel {{.*}}
+    h.single_task<class kernelA>([=]() {
+      // CHECK: printf(ptr noundef nonnull dereferenceable(1) @.str, i32 noundef 24)
+        __builtin_printf("hello, %d\n", 24);
+    });
+  });
+  return 0;
+}

clang/test/SemaSYCL/remove-restriction-builtin-printf.cpp

@@ -0,0 +1,19 @@
+// RUN: %clang_cc1 -fsycl-is-device -internal-isystem %S/Inputs -sycl-std=2020 -verify -fsyntax-only %s
+// This test checks if __builtin_printf does not throw an error when
+// called from within device code.
+
+#include "sycl.hpp"
+
+using namespace sycl;
+queue q;
+
+int main() {
+  // expected-no-diagnostics
+  q.submit([&](handler &h) {
+    h.single_task<class kernelA>([=]() {
+        __builtin_printf("hello, %d\n", 23);
+    });
+  });
+  return 0;
+}
+