On 11/07/2013 02:14 PM, Easwaran Raman wrote:
Before r193504, if a method can not be overridden, LOOKUP_NONVIRTUAL is set and the call is direct. The changes at r193504 (to fix PR c++/11750) caused a regression to this behavior. This patch attempts to fix that. Bootstraps and no test regressions on x86_64/linux. Is this a correct fix and is this ok for trunk?
Thanks; I adjusted a couple of comments to be clearer, and changed TREE_TYPE to BINFO_TYPE. Here's what I've checked in:
commit 6e2a16c94d25ad3489e21c0bb1ea238a3a27c9f7 Author: Easwaran Raman <era...@google.com> Date: Thu Nov 7 11:14:52 2013 -0800 PR c++/59031 * call.c (build_new_method_call_1): Comnpare function context with BASELINK_BINFO type rather than instance type before marking the call with LOOKUP_NONVIRTUAL. diff --git a/gcc/cp/call.c b/gcc/cp/call.c index 6a4386e..4107afa 100644 --- a/gcc/cp/call.c +++ b/gcc/cp/call.c @@ -7514,7 +7514,7 @@ build_new_method_call_1 (tree instance, tree fns, vec<tree, va_gc> **args, struct z_candidate *candidates = 0, *cand; tree explicit_targs = NULL_TREE; tree basetype = NULL_TREE; - tree access_binfo; + tree access_binfo, binfo; tree optype; tree first_mem_arg = NULL_TREE; tree name; @@ -7553,6 +7553,7 @@ build_new_method_call_1 (tree instance, tree fns, vec<tree, va_gc> **args, if (!conversion_path) conversion_path = BASELINK_BINFO (fns); access_binfo = BASELINK_ACCESS_BINFO (fns); + binfo = BASELINK_BINFO (fns); optype = BASELINK_OPTYPE (fns); fns = BASELINK_FUNCTIONS (fns); if (TREE_CODE (fns) == TEMPLATE_ID_EXPR) @@ -7799,13 +7800,13 @@ build_new_method_call_1 (tree instance, tree fns, vec<tree, va_gc> **args, { /* Optimize away vtable lookup if we know that this function can't be overridden. We need to check if - the context and the instance type are the same, + the context and the type where we found fn are the same, actually FN might be defined in a different class type because of a using-declaration. In this case, we do not want to perform a non-virtual call. */ if (DECL_VINDEX (fn) && ! (flags & LOOKUP_NONVIRTUAL) && same_type_ignoring_top_level_qualifiers_p - (DECL_CONTEXT (fn), TREE_TYPE (instance)) + (DECL_CONTEXT (fn), BINFO_TYPE (binfo)) && resolves_to_fixed_type_p (instance, 0)) flags |= LOOKUP_NONVIRTUAL; if (explicit_targs) diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h index 4e26bd5..1fc4b59 100644 --- a/gcc/cp/cp-tree.h +++ b/gcc/cp/cp-tree.h @@ -359,7 +359,8 @@ struct GTY(()) tree_overload { /* Returns true iff NODE is a BASELINK. */ #define BASELINK_P(NODE) \ (TREE_CODE (NODE) == BASELINK) -/* The BINFO indicating the base from which the BASELINK_FUNCTIONS came. */ +/* The BINFO indicating the base in which lookup found the + BASELINK_FUNCTIONS. */ #define BASELINK_BINFO(NODE) \ (((struct tree_baselink*) BASELINK_CHECK (NODE))->binfo) /* The functions referred to by the BASELINK; either a FUNCTION_DECL, diff --git a/gcc/testsuite/g++.dg/inherit/virtual11.C b/gcc/testsuite/g++.dg/inherit/virtual11.C new file mode 100644 index 0000000..04c2412 --- /dev/null +++ b/gcc/testsuite/g++.dg/inherit/virtual11.C @@ -0,0 +1,17 @@ +// PR c++/59031 +// { dg-do compile } +// { dg-options "-fdump-tree-gimple " } +class B { + public: + virtual int add (int a, int b) {return a+ b;} +}; + +class D : public B { +}; + +int foo (int a, int b) { + D d; + return d.add(a, b); +} +// { dg-final { scan-tree-dump-not "OBJ_TYPE_REF" "gimple" } } +// { dg-final { cleanup-tree-dump "gimple" } }