[SYCL][Driver] Improve the diagnostic for FPGA device link errors

clang/include/clang/Driver/Job.h

@@ -11,6 +11,7 @@
 
 #include "clang/Basic/LLVM.h"
 #include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/Optional.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringRef.h"
@@ -39,6 +40,10 @@ struct CrashReportInfo {
 /// Command - An executable path/name and argument vector to
 /// execute.
 class Command {
+public:
+  using ErrorCodeDiagMapTy = llvm::DenseMap<int, std::string>;
+
+private:
   /// Source - The action which caused the creation of this job.
   const Action &Source;
 
@@ -48,6 +53,18 @@ class Command {
   /// The executable to run.
   const char *Executable;
 
+  /// The container for custom driver-set diagnostic messages that are
+  /// produced upon particular error codes returned by the command.
+  /// In order to add such a diagnostic for an external tool, consider the
+  /// following criteria:
+  /// 1) Does the command's executable return different codes upon different
+  ///    types of errors?
+  /// 2) If the executable provides a single error code for various error types,
+  ///    is only a certain type of failure expected to occur within the driver
+  ///    flow? E.g. the driver guarantees a valid input to the tool, so any
+  ///    "invalid input" error can be ruled out
+  ErrorCodeDiagMapTy ErrorCodeDiagMap;
+
   /// The list of program arguments (not including the implicit first
   /// argument, which will be the executable).
   llvm::opt::ArgStringList Arguments;
@@ -100,6 +117,15 @@ class Command {
   virtual int Execute(ArrayRef<Optional<StringRef>> Redirects,
                       std::string *ErrMsg, bool *ExecutionFailed) const;
 
+  /// Store a custom driver diagnostic message upon a particular error code
+  /// returned by the command
+  void addDiagForErrorCode(int ErrorCode, StringRef CustomDiag);
+
+  /// Get the custom driver diagnostic message for a particular error code
+  /// if such was stored. Returns an empty string if no diagnostic message
+  /// was found for the given error code.
+  StringRef getDiagForErrorCode(int ErrorCode) const;
+
   /// getSource - Return the Action which caused the creation of this job.
   const Action &getSource() const { return Source; }
 

clang/lib/Driver/Driver.cpp

@@ -1686,7 +1686,7 @@ int Driver::ExecuteCompilation(
     // diagnostics, so always print the diagnostic there.
     const Tool &FailingTool = FailingCommand->getCreator();
 
-    if (!FailingCommand->getCreator().hasGoodDiagnostics() || CommandRes != 1) {
+    if (!FailingTool.hasGoodDiagnostics() || CommandRes != 1) {
       // FIXME: See FIXME above regarding result code interpretation.
       if (CommandRes < 0)
         Diag(clang::diag::err_drv_command_signalled)
@@ -1695,6 +1695,10 @@ int Driver::ExecuteCompilation(
         Diag(clang::diag::err_drv_command_failed)
             << FailingTool.getShortName() << CommandRes;
     }
+
+    auto CustomDiag = FailingCommand->getDiagForErrorCode(CommandRes);
+    if (!CustomDiag.empty())
+      Diag(clang::diag::note_drv_command_failed_diag_msg) << CustomDiag;
   }
   return Res;
 }

clang/lib/Driver/Job.cpp

@@ -173,6 +173,17 @@ void Command::buildArgvForResponseFile(
   }
 }
 
+void Command::addDiagForErrorCode(int ErrorCode, StringRef CustomDiag) {
+  ErrorCodeDiagMap[ErrorCode] = CustomDiag.str();
+}
+
+StringRef Command::getDiagForErrorCode(int ErrorCode) const {
+  auto ErrorCodeDiagIt = ErrorCodeDiagMap.find(ErrorCode);
+  if (ErrorCodeDiagIt != ErrorCodeDiagMap.end())
+    return ErrorCodeDiagIt->second;
+  return StringRef();
+}
+
 /// Rewrite relative include-like flag paths to absolute ones.
 static void
 rewriteIncludes(const llvm::ArrayRef<const char *> &Args, size_t Idx,

clang/lib/Driver/ToolChains/Clang.cpp

@@ -7431,18 +7431,29 @@ void SPIRCheck::ConstructJob(Compilation &C, const JobAction &JA,
   // we need to exit.  The expected output is the input as this is just an
   // intermediate check with no functional change.
   ArgStringList CheckArgs;
-  for (auto I : Inputs) {
-    CheckArgs.push_back(I.getFilename());
-  }
+  assert(Inputs.size() == 1 && "Unexpected number of inputs to the tool");
+  const InputInfo &InputFile = Inputs.front();
+  CheckArgs.push_back(InputFile.getFilename());
 
   // Add output file, which is just a copy of the input to better fit in the
   // toolchain flow.
   CheckArgs.push_back("-o");
   CheckArgs.push_back(Output.getFilename());
-
-  C.addCommand(std::make_unique<Command>(JA, *this,
+  auto Cmd = std::make_unique<Command>(
+      JA, *this,
       TCArgs.MakeArgString(getToolChain().GetProgramPath(getShortName())),
-      CheckArgs, None));
+      CheckArgs, None);
+
+  if (getToolChain().getTriple().getSubArch() ==
+      llvm::Triple::SPIRSubArch_fpga) {
+    const char *Msg = TCArgs.MakeArgString(
+        Twine("The FPGA image does not include all device kernels from ") +
+        Twine(InputFile.getBaseInput()) +
+        Twine(". Please re-generate the image"));
+    Cmd->addDiagForErrorCode(/*ErrorCode*/ 1, Msg);
+  }
+
+  C.addCommand(std::move(Cmd));
 }
 
 void SYCLPostLink::ConstructJob(Compilation &C, const JobAction &JA,

clang/lib/Driver/ToolChains/Clang.h

@@ -199,6 +199,7 @@ class LLVM_LIBRARY_VISIBILITY SYCLPostLink final : public Tool {
       : Tool("SYCL post link", "sycl-post-link", TC) {}
 
   bool hasIntegratedCPP() const override { return false; }
+  bool hasGoodDiagnostics() const override { return true; }
   void ConstructJob(Compilation &C, const JobAction &JA,
                     const InputInfo &Output, const InputInfoList &Inputs,
                     const llvm::opt::ArgList &TCArgs,

sycl/test/fpga_tests/fpga_device_link_diag.cpp

@@ -0,0 +1,25 @@
+//==----- fpga_device_link_diag.cpp - SYCL FPGA linking diagnostic test ----==//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// REQUIRES: aoc, accelerator
+
+// RUN: %clangxx -fsycl -fintelfpga %s -c -o test_obj.o
+// RUN: touch dummy.cpp
+// RUN: %clangxx -fsycl -fintelfpga dummy.cpp -c
+// RUN: %clangxx -fsycl -fintelfpga -fsycl-link=image dummy.o -o dummy_arch.a
+// RUN: not %clangxx -fsycl -fintelfpga test_obj.o dummy_arch.a 2>&1 | FileCheck %s --check-prefix=CHK-FPGA-LINK-DIAG
+// CHK-FPGA-LINK-DIAG: note: diagnostic msg: The FPGA image does not include all device kernels from test_obj.o. Please re-generate the image
+
+template <typename name, typename Func>
+__attribute__((sycl_kernel)) void kernel_single_task(Func kernelFunc) {
+  kernelFunc();
+}
+
+void foo() {
+  kernel_single_task<class kernel>([]() {});
+}