[SYCL] Allow device code to be exported by a Windows DLL (intel#14962)

Allow device code to be exported by a Windows DLL.

---------

Signed-off-by: Lu, John <[email protected]>

Author: LU-JOHN

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -12372,7 +12372,6 @@ def err_sycl_restrict : Error<
   "|call through a function pointer"
   "|allocate storage"
   "|use inline assembly"
-  "|call a dllimport function"
   "|call a variadic function"
   "|call an undefined function without SYCL_EXTERNAL attribute"
   "|use a const static or global variable that is neither zero-initialized "

clang/include/clang/Sema/SemaSYCL.h

@@ -308,7 +308,6 @@ class SemaSYCL : public SemaBase {
     KernelCallFunctionPointer,
     KernelAllocateStorage,
     KernelUseAssembly,
-    KernelCallDllimportFunction,
     KernelCallVariadicFunction,
     KernelCallUndefinedFunction,
     KernelConstStaticVariable

clang/lib/Sema/SemaSYCL.cpp

@@ -598,18 +598,6 @@ class DiagDeviceFunction : public RecursiveASTVisitor<DiagDeviceFunction> {
             << SemaSYCL::KernelCallRecursiveFunction;
       }
 
-      if (auto const *FD = dyn_cast<FunctionDecl>(Callee)) {
-        // FIXME: We need check all target specified attributes for error if
-        // that function with attribute can not be called from sycl kernel.  The
-        // info is in ParsedAttr. We don't have to map from Attr to ParsedAttr
-        // currently. Erich is currently working on that in LLVM, once that is
-        // committed we need to change this".
-        if (FD->hasAttr<DLLImportAttr>()) {
-          SemaSYCLRef.Diag(e->getExprLoc(), diag::err_sycl_restrict)
-              << SemaSYCL::KernelCallDllimportFunction;
-          SemaSYCLRef.Diag(FD->getLocation(), diag::note_callee_decl) << FD;
-        }
-      }
       // Specifically check if the math library function corresponding to this
       // builtin is supported for SYCL
       unsigned BuiltinID = Callee->getBuiltinID();

clang/test/SemaSYCL/sycl-dllimport-dllexport.cpp

@@ -36,14 +36,13 @@ int zoo() __attribute__((dllimport));
 
 #else
 
-// emit error if dllimport function is called in sycl kernel
 int  __declspec(dllexport) foo(int a) {
    return a;
 }
-// expected-note@+1 {{'bar' declared here}}
+
 SYCL_EXTERNAL int __declspec(dllimport) bar();
 // expected-note@+1 {{previous declaration is here}}
-int __declspec(dllimport) foobar(); // expected-note {{'foobar' declared here}}
+int __declspec(dllimport) foobar();
 int foobar()  // expected-warning {{'foobar' redeclared without 'dllimport' attribute: 'dllexport' attribute added}}
 {
   return 10;
@@ -59,8 +58,8 @@ int main() {
   bar();  // expected-no-error
   kernel_single_task<class fake_kernel>([]() {
     foo(10);// expected-no-error
-    bar(); // expected-error {{SYCL kernel cannot call a dllimport function}}
-    foobar(); // expected-error {{SYCL kernel cannot call a dllimport function}}
+    bar();
+    foobar();
   });
   bar();  // expected-no-error
   return 0;

sycl/test-e2e/DeviceDependencies/Inputs/a.cpp

@@ -1,13 +1,13 @@
-#include <iostream>
+#define A_EXPORT
 #include "a.hpp"
 #include "b.hpp"
+#include <iostream>
 
-SYCL_EXTERNAL int levelA(int val) {
+A_DECLSPEC SYCL_EXTERNAL int levelA(int val) {
 #ifndef __SYCL_DEVICE_ONLY__
   std::cerr << "Host symbol used" << std::endl;
-  return 0;
+  val ^= 0x1234;
 #endif
   val=levelB(val);
   return val|=(0xA<<0);
 }
-

sycl/test-e2e/DeviceDependencies/Inputs/a.hpp

@@ -1,3 +1,13 @@
 #include <sycl/detail/core.hpp>
 
-SYCL_EXTERNAL int levelA(int val);
+#if defined(MAKE_DLL)
+#ifdef A_EXPORT
+#define A_DECLSPEC __declspec(dllexport)
+#else
+#define A_DECLSPEC __declspec(dllimport)
+#endif
+#else
+#define A_DECLSPEC
+#endif
+
+A_DECLSPEC SYCL_EXTERNAL int levelA(int val);

sycl/test-e2e/DeviceDependencies/Inputs/b.cpp

@@ -1,13 +1,13 @@
-#include <iostream>
+#define B_EXPORT
 #include "b.hpp"
 #include "c.hpp"
+#include <iostream>
 
-SYCL_EXTERNAL int levelB(int val) {
+B_DECLSPEC SYCL_EXTERNAL int levelB(int val) {
 #ifndef __SYCL_DEVICE_ONLY__
   std::cerr << "Host symbol used" << std::endl;
-  return 0;
+  val ^= 0x2345;
 #endif
   val=levelC(val);  
   return val|=(0xB<<4);
 }
-

sycl/test-e2e/DeviceDependencies/Inputs/b.hpp

@@ -1,3 +1,13 @@
 #include <sycl/detail/core.hpp>
 
-SYCL_EXTERNAL int levelB(int val);
+#if defined(MAKE_DLL)
+#ifdef B_EXPORT
+#define B_DECLSPEC __declspec(dllexport)
+#else
+#define B_DECLSPEC __declspec(dllimport)
+#endif
+#else
+#define B_DECLSPEC
+#endif
+
+B_DECLSPEC SYCL_EXTERNAL int levelB(int val);

sycl/test-e2e/DeviceDependencies/Inputs/c.cpp

@@ -1,13 +1,13 @@
-#include <iostream>
+#define C_EXPORT
 #include "c.hpp"
 #include "d.hpp"
+#include <iostream>
 
-SYCL_EXTERNAL int levelC(int val) {
+C_DECLSPEC SYCL_EXTERNAL int levelC(int val) {
 #ifndef __SYCL_DEVICE_ONLY__
   std::cerr << "Host symbol used" << std::endl;
-  return 0;
+  val ^= 0x3456;
 #endif
   val=levelD(val);  
   return val|=(0xC<<8);
 }
-

sycl/test-e2e/DeviceDependencies/Inputs/c.hpp

@@ -1,3 +1,13 @@
 #include <sycl/detail/core.hpp>
 
-SYCL_EXTERNAL int levelC(int val);
+#if defined(MAKE_DLL)
+#ifdef C_EXPORT
+#define C_DECLSPEC __declspec(dllexport)
+#else
+#define C_DECLSPEC __declspec(dllimport)
+#endif
+#else
+#define C_DECLSPEC
+#endif
+
+C_DECLSPEC SYCL_EXTERNAL int levelC(int val);