Fix scope-based lookup when more than one function is found.

When multiple functions are found by name, lldb removes duplicate entries of
functions with the same type, so the first function in the symbol context list
is chosen, even if it isn't in scope. This patch uses the declaration context
of the execution context to select the function which is in scope.

This fixes cases like the following:

    int func();
    namespace ns {
	int func();
	void here() {
	    // Run to BP here and eval 'p func()';
	    // lldb used to find ::func(), now finds ns::func().
	}
    }

Reviewed by: clayborg
Subscribers: lldb-commits
Differential Revision: http://reviews.llvm.org/D15312

llvm-svn: 255439

6 files changed, 169 insertions, 2 deletions

diff --git a/lldb/packages/Python/lldbsuite/test/lang/cpp/namespace/Makefile b/lldb/packages/Python/lldbsuite/test/lang/cpp/namespace/Makefile
index 314f1cb2f07..7dd5eb4c11f 100644
--- a/lldb/packages/Python/lldbsuite/test/lang/cpp/namespace/Makefile
+++ b/lldb/packages/Python/lldbsuite/test/lang/cpp/namespace/Makefile
@@ -1,5 +1,5 @@
 LEVEL = ../../../make
 
-CXX_SOURCES := main.cpp
+CXX_SOURCES := main.cpp ns.cpp ns2.cpp ns3.cpp
 
 include $(LEVEL)/Makefile.rules
diff --git a/lldb/packages/Python/lldbsuite/test/lang/cpp/namespace/main.cpp b/lldb/packages/Python/lldbsuite/test/lang/cpp/namespace/main.cpp
index 4de7a1ada8d..560ec40f473 100644
--- a/lldb/packages/Python/lldbsuite/test/lang/cpp/namespace/main.cpp
+++ b/lldb/packages/Python/lldbsuite/test/lang/cpp/namespace/main.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 #include <cstdarg>
+#include "ns.h"
 
 namespace {
     typedef unsigned int my_uint_t;
@@ -80,7 +81,6 @@ namespace ns2 {
     int value = 200;
 }
 
-#include <stdio.h>
 void test_namespace_scopes() {
     do {
         using namespace ns1;
@@ -113,5 +113,12 @@ int Foo::myfunc(int a)
 int
 main (int argc, char const *argv[])
 {
+    test_lookup_at_global_scope();
+    test_lookup_at_file_scope();
+    A::test_lookup_at_ns_scope();
+    A::B::test_lookup_at_nested_ns_scope();
+    A::B::test_lookup_at_nested_ns_scope_after_using();
+    test_lookup_before_using_directive();
+    test_lookup_after_using_directive();
     return Foo::myfunc(12);
 }
diff --git a/lldb/packages/Python/lldbsuite/test/lang/cpp/namespace/ns.cpp b/lldb/packages/Python/lldbsuite/test/lang/cpp/namespace/ns.cpp
new file mode 100644
index 00000000000..9e5637d02b4
--- /dev/null
+++ b/lldb/packages/Python/lldbsuite/test/lang/cpp/namespace/ns.cpp
@@ -0,0 +1,32 @@
+//===-- ns.cpp ------------------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "ns.h"
+
+int foo()
+{
+    printf("global foo()\n");
+    return 42;
+}
+int func()
+{
+    printf("global func()\n");
+    return 1;
+}
+int func(int a)
+{
+    printf("global func(int)\n");
+    return a + 1;
+}
+void test_lookup_at_global_scope()
+{
+    // BP_global_scope
+    printf("at global scope: foo() = %d\n", foo()); // eval foo(), exp: 42
+    printf("at global scope: func() = %d\n", func()); // eval func(), exp: 1
+}
diff --git a/lldb/packages/Python/lldbsuite/test/lang/cpp/namespace/ns.h b/lldb/packages/Python/lldbsuite/test/lang/cpp/namespace/ns.h
new file mode 100644
index 00000000000..a07b600efa3
--- /dev/null
+++ b/lldb/packages/Python/lldbsuite/test/lang/cpp/namespace/ns.h
@@ -0,0 +1,36 @@
+//===-- ns.h ------------------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include <stdio.h>
+
+void test_lookup_at_global_scope();
+void test_lookup_at_file_scope();
+void test_lookup_before_using_directive();
+void test_lookup_after_using_directive();
+int func(int a);
+namespace A {
+    int foo();
+    int func(int a);
+    inline int func()
+    {
+        printf("A::func()\n");
+        return 3;
+    }
+    inline int func2()
+    {
+        printf("A::func2()\n");
+        return 3;
+    }
+    void test_lookup_at_ns_scope();
+    namespace B {
+        int func();
+        void test_lookup_at_nested_ns_scope();
+        void test_lookup_at_nested_ns_scope_after_using();
+    }
+}
diff --git a/lldb/packages/Python/lldbsuite/test/lang/cpp/namespace/ns2.cpp b/lldb/packages/Python/lldbsuite/test/lang/cpp/namespace/ns2.cpp
new file mode 100644
index 00000000000..04046ad9b7f
--- /dev/null
+++ b/lldb/packages/Python/lldbsuite/test/lang/cpp/namespace/ns2.cpp
@@ -0,0 +1,65 @@
+//===-- ns2.cpp ------------------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "ns.h"
+
+static int func()
+{
+    printf("static m2.cpp func()\n");
+    return 2;
+}
+void test_lookup_at_file_scope()
+{
+    // BP_file_scope
+    printf("at file scope: func() = %d\n", func()); // eval func(), exp: 2
+    printf("at file scope: func(10) = %d\n", func(10)); // eval func(10), exp: 11
+}
+namespace A {
+    namespace B {
+        int func()
+        {
+            printf("A::B::func()\n");
+            return 4;
+        }
+        void test_lookup_at_nested_ns_scope()
+        {
+            // BP_nested_ns_scope
+            printf("at nested ns scope: func() = %d\n", func()); // eval func(), exp: 4
+
+            //printf("func(10) = %d\n", func(10)); // eval func(10), exp: 13
+            // NOTE: Under the rules of C++, this test would normally get an error
+            // because A::B::func() hides A::func(), but lldb intentionally
+            // disobeys these rules so that the intended overload can be found
+            // by only removing duplicates if they have the same type.
+        }
+        void test_lookup_at_nested_ns_scope_after_using()
+        {
+            // BP_nested_ns_scope_after_using
+            using A::func;
+            printf("at nested ns scope after using: func() = %d\n", func()); // eval func(), exp: 3
+        }
+    }
+}
+int A::foo()
+{
+    printf("A::foo()\n");
+    return 42;
+}
+int A::func(int a)
+{
+    printf("A::func(int)\n");
+    return a + 3;
+}
+void A::test_lookup_at_ns_scope()
+{
+    // BP_ns_scope
+    printf("at nested ns scope: func() = %d\n", func()); // eval func(), exp: 3
+    printf("at nested ns scope: func(10) = %d\n", func(10)); // eval func(10), exp: 13
+    printf("at nested ns scope: foo() = %d\n", foo()); // eval foo(), exp: 42
+}
diff --git a/lldb/packages/Python/lldbsuite/test/lang/cpp/namespace/ns3.cpp b/lldb/packages/Python/lldbsuite/test/lang/cpp/namespace/ns3.cpp
new file mode 100644
index 00000000000..10b0df78422
--- /dev/null
+++ b/lldb/packages/Python/lldbsuite/test/lang/cpp/namespace/ns3.cpp
@@ -0,0 +1,27 @@
+//===-- ns3.cpp ------------------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "ns.h"
+extern int func();
+
+// Note: the following function must be before the using.
+void test_lookup_before_using_directive()
+{
+    // BP_before_using_directive
+    printf("before using directive: func() = %d\n", func()); // eval func(), exp: 1
+}
+using namespace A;
+void test_lookup_after_using_directive()
+{
+    // BP_after_using_directive
+    //printf("func() = %d\n", func()); // eval func(), exp: error, amiguous
+    printf("after using directive: func2() = %d\n", func2()); // eval func2(), exp: 3
+    printf("after using directive: ::func() = %d\n", ::func()); // eval ::func(), exp: 1
+    printf("after using directive: B::func() = %d\n", B::func()); // eval B::func(), exp: 4
+}