Improve OpenCL error messages

Add the name of the function that failed to the OpenCLError class. Log OpenCL
failure in a couple of more places (where OpenCLError is not thrown). Print
OpenCL errors symbolically instead of numerically where applicable.

Change-Id: I60f910e9ea7b75af7ec506553d7a73ad99ba4366

sc/source/core/opencl/opbase.cxx

@@ -19,10 +19,14 @@ UnhandledToken::UnhandledToken(
     formula::FormulaToken* t, const char* m, const std::string& fn, int ln ) :
     mToken(t), mMessage(m), mFile(fn), mLineNumber(ln) {}
 
-OpenCLError::OpenCLError( cl_int err, const std::string& fn, int ln ) :
-    mError(err), mFile(fn), mLineNumber(ln)
+OpenCLError::OpenCLError( const std::string function, cl_int error, const std::string& file, int line ) :
+    mFunction(function), mError(error), mFile(file), mLineNumber(line)
 {
-    SAL_INFO("sc.opencl", "OpenCL error: " << ::opencl::errorString(mError));
+    // Not sure if this SAL_INFO() is useful; the place in
+    // CLInterpreterContext::launchKernel() where OpenCLError is
+    // caught already uses SAL_WARN() to display it.
+
+    // SAL_INFO("sc.opencl", "OpenCL error: " << ::opencl::errorString(mError));
 }
 
 Unhandled::Unhandled( const std::string& fn, int ln ) :

sc/source/core/opencl/opbase.hxx

@@ -42,8 +42,9 @@ public:
 class OpenCLError
 {
 public:
-    OpenCLError( cl_int err, const std::string& fn, int ln );
+    OpenCLError( const std::string function, cl_int error, const std::string& file, int line );
 
+    std::string mFunction;
     cl_int mError;
     std::string mFile;
     int mLineNumber;