added support for pre-detecting function eval issues

7 files changed, 87 insertions, 0 deletions

diff --git a/vespalib/src/tests/eval/compiled_function/compiled_function_test.cpp b/vespalib/src/tests/eval/compiled_function/compiled_function_test.cpp
index b3777a86df9..82dffd58cdc 100644
--- a/vespalib/src/tests/eval/compiled_function/compiled_function_test.cpp
+++ b/vespalib/src/tests/eval/compiled_function/compiled_function_test.cpp
@@ -6,6 +6,8 @@
 #include <vespa/vespalib/eval/basic_nodes.h>
 #include <vespa/vespalib/util/stringfmt.h>
 #include <cmath>
+#include <vespa/vespalib/test/insertion_operators.h>
+#include <iostream>
 
 using namespace vespalib::eval;
 
@@ -169,4 +171,18 @@ TEST("require that tensor operations have sane numeric fallbacks") {
 
 //-----------------------------------------------------------------------------
 
+TEST("require function issues can be detected") {
+    auto simple = Function::parse("a+b");
+    auto complex = Function::parse("join(a,b,f(a,b)(a+b))");
+    EXPECT_FALSE(simple.has_error());
+    EXPECT_FALSE(complex.has_error());
+    EXPECT_FALSE(CompiledFunction::detect_issues(simple));
+    EXPECT_TRUE(CompiledFunction::detect_issues(complex));
+    std::cerr << "Example function issues:" << std::endl
+              << CompiledFunction::detect_issues(complex).list
+              << std::endl;
+}
+
+//-----------------------------------------------------------------------------
+
 TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/vespalib/src/tests/eval/interpreted_function/interpreted_function_test.cpp b/vespalib/src/tests/eval/interpreted_function/interpreted_function_test.cpp
index 9d01488dda1..51aacfd2272 100644
--- a/vespalib/src/tests/eval/interpreted_function/interpreted_function_test.cpp
+++ b/vespalib/src/tests/eval/interpreted_function/interpreted_function_test.cpp
@@ -7,6 +7,8 @@
 #include <vespa/vespalib/eval/basic_nodes.h>
 #include <vespa/vespalib/util/stringfmt.h>
 #include <vespa/vespalib/util/stash.h>
+#include <vespa/vespalib/test/insertion_operators.h>
+#include <iostream>
 
 using namespace vespalib::eval;
 using vespalib::Stash;
@@ -188,4 +190,18 @@ TEST("require that matrix multiplication works with tensor function") {
 
 //-----------------------------------------------------------------------------
 
+TEST("require function issues can be detected") {
+    auto simple = Function::parse("a+b");
+    auto complex = Function::parse("join(a,b,f(a,b)(a+b))");
+    EXPECT_FALSE(simple.has_error());
+    EXPECT_FALSE(complex.has_error());
+    EXPECT_FALSE(InterpretedFunction::detect_issues(simple));
+    EXPECT_TRUE(InterpretedFunction::detect_issues(complex));
+    std::cerr << "Example function issues:" << std::endl
+              << InterpretedFunction::detect_issues(complex).list
+              << std::endl;
+}
+
+//-----------------------------------------------------------------------------
+
 TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/vespalib/src/vespa/vespalib/eval/function.h b/vespalib/src/vespa/vespalib/eval/function.h
index a9e2b980025..35a89ce6512 100644
--- a/vespalib/src/vespa/vespalib/eval/function.h
+++ b/vespalib/src/vespa/vespalib/eval/function.h
@@ -67,6 +67,17 @@ public:
                        vespalib::string &wrapper,
                        vespalib::string &body,
                        vespalib::string &error);
+    /**
+     * Issues is used to report issues relating to the function
+     * structure, typically to explain why a function cannot be
+     * evaluated in a specific context due to it using features not
+     * supported in that context.
+     **/
+    struct Issues {
+        std::vector<vespalib::string> list;
+        operator bool() const { return !list.empty(); }
+        Issues(std::vector<vespalib::string> &&list_in) : list(std::move(list_in)) {}
+    };
 };
 
 } // namespace vespalib::eval
diff --git a/vespalib/src/vespa/vespalib/eval/interpreted_function.cpp b/vespalib/src/vespa/vespalib/eval/interpreted_function.cpp
index e1e04ca6ced..a4329f97de2 100644
--- a/vespalib/src/vespa/vespalib/eval/interpreted_function.cpp
+++ b/vespalib/src/vespa/vespalib/eval/interpreted_function.cpp
@@ -11,6 +11,7 @@
 #include <set>
 #include "tensor_spec.h"
 #include "simple_tensor_engine.h"
+#include <vespa/vespalib/util/classname.h>
 
 namespace vespalib {
 namespace eval {
@@ -453,5 +454,23 @@ InterpretedFunction::eval(Context &ctx) const
     return state.stack.back();
 }
 
+Function::Issues
+InterpretedFunction::detect_issues(const Function &function)
+{
+    struct NotSupported : NodeTraverser {
+        std::vector<vespalib::string> issues;
+        bool open(const nodes::Node &) override { return true; }
+        void close(const nodes::Node &node) override {
+            if (nodes::check_type<nodes::TensorMap,
+                                  nodes::TensorJoin>(node)) {
+                issues.push_back(make_string("unsupported node type: %s",
+                                getClassName(node).c_str()));
+            }
+        }
+    } checker;
+    function.root().traverse(checker);
+    return Function::Issues(std::move(checker.issues));
+}
+
 } // namespace vespalib::eval
 } // namespace vespalib
diff --git a/vespalib/src/vespa/vespalib/eval/interpreted_function.h b/vespalib/src/vespa/vespalib/eval/interpreted_function.h
index 615f9d4eb82..fa1ea6580dd 100644
--- a/vespalib/src/vespa/vespalib/eval/interpreted_function.h
+++ b/vespalib/src/vespa/vespalib/eval/interpreted_function.h
@@ -94,6 +94,7 @@ public:
     size_t program_size() const { return _program.size(); }
     size_t num_params() const { return _num_params; }
     const Value &eval(Context &ctx) const;
+    static Function::Issues detect_issues(const Function &function);
 };
 
 } // namespace vespalib::eval
diff --git a/vespalib/src/vespa/vespalib/eval/llvm/compiled_function.cpp b/vespalib/src/vespa/vespalib/eval/llvm/compiled_function.cpp
index 957df7503c3..9b120b677e2 100644
--- a/vespalib/src/vespa/vespalib/eval/llvm/compiled_function.cpp
+++ b/vespalib/src/vespa/vespalib/eval/llvm/compiled_function.cpp
@@ -3,6 +3,10 @@
 #include <vespa/fastos/fastos.h>
 #include "compiled_function.h"
 #include <vespa/vespalib/util/benchmark_timer.h>
+#include <vespa/vespalib/eval/node_traverser.h>
+#include <vespa/vespalib/eval/check_type.h>
+#include <vespa/vespalib/eval/tensor_nodes.h>
+#include <vespa/vespalib/util/classname.h>
 
 namespace vespalib {
 namespace eval {
@@ -46,5 +50,24 @@ CompiledFunction::estimate_cost_us(const std::vector<double> &params) const
     return BenchmarkTimer::benchmark(actual, baseline, 4.0) * 1000.0 * 1000.0;
 }
 
+Function::Issues
+CompiledFunction::detect_issues(const Function &function)
+{
+    struct NotSupported : NodeTraverser {
+        std::vector<vespalib::string> issues;
+        bool open(const nodes::Node &) override { return true; }
+        void close(const nodes::Node &node) override {
+            if (nodes::check_type<nodes::TensorSum,
+                                  nodes::TensorMap,
+                                  nodes::TensorJoin>(node)) {
+                issues.push_back(make_string("unsupported node type: %s",
+                                getClassName(node).c_str()));
+            }
+        }
+    } checker;
+    function.root().traverse(checker);
+    return Function::Issues(std::move(checker.issues));
+}
+
 } // namespace vespalib::eval
 } // namespace vespalib
diff --git a/vespalib/src/vespa/vespalib/eval/llvm/compiled_function.h b/vespalib/src/vespa/vespalib/eval/llvm/compiled_function.h
index cd7ae2189b8..3b10d9a20c5 100644
--- a/vespalib/src/vespa/vespalib/eval/llvm/compiled_function.h
+++ b/vespalib/src/vespa/vespalib/eval/llvm/compiled_function.h
@@ -56,6 +56,7 @@ public:
     }
     void dump() const { _llvm_wrapper.dump(); }
     double estimate_cost_us(const std::vector<double> &params) const;
+    static Function::Issues detect_issues(const Function &function);
 };
 
 } // namespace vespalib::eval