From 50d4b4b28071dd455139f45f8b48698d9f8f0326 Mon Sep 17 00:00:00 2001
From: Premanand M Rao <premanand.m.rao@intel.com>
Date: Tue, 17 Sep 2019 08:57:45 -0700
Subject: [PATCH] [SYCL] Diagnose violations from function object passed to the
 kernel

Scan the body of the routine passed as a function object to the SYCL
kernel.  The call graph traversed previously to emit deferred
diagnostics was missing the passed function object.

Signed-off-by: Premanand M Rao <premanand.m.rao@intel.com>
---
 clang/lib/Sema/Sema.cpp                | 25 +++++++++++++++++++++++++
 clang/lib/Sema/SemaSYCL.cpp            | 12 ------------
 clang/test/SemaSYCL/diag-fobj-call.cpp | 15 +++++++++++++++
 clang/test/SemaSYCL/inline-asm.cpp     |  1 +
 clang/test/SemaSYCL/sycl-restrict.cpp  |  1 -
 5 files changed, 41 insertions(+), 13 deletions(-)
 create mode 100644 clang/test/SemaSYCL/diag-fobj-call.cpp

diff --git a/clang/lib/Sema/Sema.cpp b/clang/lib/Sema/Sema.cpp
index 385c7064e1d3c..7f7c455b1f7e0 100644
--- a/clang/lib/Sema/Sema.cpp
+++ b/clang/lib/Sema/Sema.cpp
@@ -1386,6 +1386,13 @@ Sema::Diag(SourceLocation Loc, const PartialDiagnostic& PD) {
 static void emitCallStackNotes(Sema &S, FunctionDecl *FD) {
   auto FnIt = S.DeviceKnownEmittedFns.find(FD);
   while (FnIt != S.DeviceKnownEmittedFns.end()) {
+    if (S.getLangOpts().SYCLIsDevice &&
+        FnIt->second.FD->hasAttr<SYCLKernelAttr>()) {
+      // Skip over the routines with sycl_kernel attributes
+      // in the traceback as they are likely from SYCL headers.
+      FnIt = S.DeviceKnownEmittedFns.find(FnIt->second.FD);
+      continue;
+    }
     DiagnosticBuilder Builder(
         S.Diags.Report(FnIt->second.Loc, diag::note_called_by));
     Builder << FnIt->second.FD;
@@ -1533,6 +1540,24 @@ void Sema::markKnownEmitted(
       }
     }
 
+    // Function object calls are not walked above.
+    // Extract the call expression from the statement block.
+    FunctionDecl *FD = C.Callee->getDefinition();
+    const CompoundStmt *CS = FD ? dyn_cast_or_null<CompoundStmt>(FD->getBody())
+                                : nullptr;
+    if (CS)
+      for (auto *I : CS->body()) {
+        FunctionDecl *D = nullptr;
+        CallExpr *CE = dyn_cast<CallExpr>(I);
+        if (CE)
+          D = dyn_cast_or_null<FunctionDecl>(CE->getCalleeDecl());
+        if (!D || Seen.count(D) || IsKnownEmitted(S, D))
+          continue;
+        Seen.insert(D);
+        Worklist.push_back(
+            {/* Caller = */ C.Callee, /* Callee = */ D, CE->getBeginLoc()});
+      }
+
     // Add all functions called by Callee to our worklist.
     auto CGIt = S.DeviceCallGraph.find(C.Callee);
     if (CGIt == S.DeviceCallGraph.end())
diff --git a/clang/lib/Sema/SemaSYCL.cpp b/clang/lib/Sema/SemaSYCL.cpp
index 09e66dcda9065..ff888da86cde3 100644
--- a/clang/lib/Sema/SemaSYCL.cpp
+++ b/clang/lib/Sema/SemaSYCL.cpp
@@ -354,18 +354,6 @@ class MarkDeviceFunction : public RecursiveASTVisitor<MarkDeviceFunction> {
     return true;
   }
   
-  bool VisitGCCAsmStmt(GCCAsmStmt *S) {
-    SemaRef.Diag(S->getBeginLoc(), diag::err_sycl_restrict)
-        << Sema::KernelUseAssembly;
-    return true;
-  }
- 
-  bool VisitMSAsmStmt(MSAsmStmt *S) {
-    SemaRef.Diag(S->getBeginLoc(), diag::err_sycl_restrict)
-        << Sema::KernelUseAssembly;
-    return true;
-  }
-
   // The call graph for this translation unit.
   CallGraph SYCLCG;
   // The set of functions called by a kernel function.
diff --git a/clang/test/SemaSYCL/diag-fobj-call.cpp b/clang/test/SemaSYCL/diag-fobj-call.cpp
new file mode 100644
index 0000000000000..45b43ed427e0f
--- /dev/null
+++ b/clang/test/SemaSYCL/diag-fobj-call.cpp
@@ -0,0 +1,15 @@
+// RUN: %clang_cc1 -fcxx-exceptions -fsycl-is-device -fsyntax-only -verify %s
+
+void bar() { throw 5; } // expected-no-error
+void foo() { throw 10; } // expected-error {{SYCL kernel cannot use exceptions}}
+
+template <typename name, typename Func>
+__attribute__((sycl_kernel)) void kernel_single_task(Func kernelFunc) {
+  kernelFunc();
+}
+
+int main() {
+  // expected-note@+1 {{called by 'operator()'}}
+  kernel_single_task<class fake_kernel>([]() { foo(); });
+  bar();
+}
diff --git a/clang/test/SemaSYCL/inline-asm.cpp b/clang/test/SemaSYCL/inline-asm.cpp
index cab5ff20b2659..3cefa4f4ad393 100644
--- a/clang/test/SemaSYCL/inline-asm.cpp
+++ b/clang/test/SemaSYCL/inline-asm.cpp
@@ -26,6 +26,7 @@ __attribute__((sycl_kernel)) void kernel_single_task(Func kernelFunc) {
 
 int main() {
   foo();
+  // expected-note@+1 {{called by 'operator()'}}
   kernel_single_task<class fake_kernel>([]() { bar(); });
   return 0;
 }
diff --git a/clang/test/SemaSYCL/sycl-restrict.cpp b/clang/test/SemaSYCL/sycl-restrict.cpp
index 8c6fdb1ac7212..48cfd1b3e15a1 100644
--- a/clang/test/SemaSYCL/sycl-restrict.cpp
+++ b/clang/test/SemaSYCL/sycl-restrict.cpp
@@ -188,7 +188,6 @@ __attribute__((sycl_kernel)) void kernel_single_task(Func kernelFunc) {
   kernelFunc();
   a_type ab;
   a_type *p;
-  // expected-note@+1 {{called by 'kernel_single_task'}}
   use2(ab, p);
 }