| Message ID | 20221220153034.2746407-1-ppalka@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | c++, tree: walk TREE_VEC (and VECTOR_CST) in natural order [PR101886] | expand |
On 12/20/22 10:30, Patrick Palka wrote: > Unfortunately the extract_autos_r fix in r13-4799-ga7c8036b26082d is > derailed by the fact that walk_tree_1 currently walks the elements of a > TREE_VEC in reverse, which means for A<auto, auto> in the below testcase > extract_autos_r ends up adjusting the TEMPLATE_TYPE_IDX of the first > auto rather than the second one, and the first auto is the canonical > auto of level 2 and index 0, so we rightfully trigger the sanity check > added in that commit. > > It seems TREE_VEC and VECTOR_CST are the only trees that we walk in > reverse, and this has been the case since r21884 whence the original > version of walk_tree_1 was introduced. But that's arguably unnatural > and inconsistent with how we walk other compound trees such as > CONSTRUCTORs and EXPR_P trees. So this patch makes walk_tree_1 walk > these trees in forward order, which fixes the below testcase. This in > turn revealed that keep_template_parm builds up the list of found > template parameters in reverse, which previously compensated for the > TREE_VEC behavior, but now we should be building the list in the natural > order as well for sake of pretty printing parameter mappings. > > Bootstrapped and regtested on x86_64-pc-linux-gnu with > --enable-languages=all,ada,go does this look OK for trunk? OK. > PR c++/101886 > > gcc/cp/ChangeLog: > > * pt.cc (find_template_parameter_info::parm_list_tail): > New data member. > (keep_template_parm): Use parm_list_tail to append rather > than prepend to parm_list. > > gcc/ChangeLog: > > * tree.cc (walk_tree_1) <case TREE_VEC>: Walk the elements > in the natural order. > <case VECTOR_CST>: Likewise. > > gcc/testsuite/ChangeLog: > > * g++.dg/concepts/diagnostic12.C: Adjust expected order of > template parameters within parameter mapping. > * g++.dg/concepts/auto6.C: New test. > --- > gcc/cp/pt.cc | 13 +++++++++---- > gcc/testsuite/g++.dg/concepts/auto6.C | 14 ++++++++++++++ > gcc/testsuite/g++.dg/concepts/diagnostic12.C | 2 +- > gcc/tree.cc | 20 ++++++++++---------- > 4 files changed, 34 insertions(+), 15 deletions(-) > create mode 100644 gcc/testsuite/g++.dg/concepts/auto6.C > > diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc > index 2b7b3756b68..df125a63785 100644 > --- a/gcc/cp/pt.cc > +++ b/gcc/cp/pt.cc > @@ -10640,14 +10640,14 @@ for_each_template_parm (tree t, tree_fn_t fn, void* data, > struct find_template_parameter_info > { > explicit find_template_parameter_info (tree ctx_parms) > - : parm_list (NULL_TREE), > - ctx_parms (ctx_parms), > + : ctx_parms (ctx_parms), > max_depth (TMPL_PARMS_DEPTH (ctx_parms)) > {} > > hash_set<tree> visited; > hash_set<tree> parms; > - tree parm_list; > + tree parm_list = NULL_TREE; > + tree *parm_list_tail = &parm_list; > tree ctx_parms; > int max_depth; > }; > @@ -10693,7 +10693,12 @@ keep_template_parm (tree t, void* data) > if (TYPE_P (t)) > t = TYPE_MAIN_VARIANT (t); > if (!ftpi->parms.add (t)) > - ftpi->parm_list = tree_cons (NULL_TREE, t, ftpi->parm_list); > + { > + /* Append T to PARM_LIST. */ > + tree node = build_tree_list (NULL_TREE, t); > + *ftpi->parm_list_tail = node; > + ftpi->parm_list_tail = &TREE_CHAIN (node); > + } > > /* Verify the parameter we found has a valid index. */ > if (flag_checking) > diff --git a/gcc/testsuite/g++.dg/concepts/auto6.C b/gcc/testsuite/g++.dg/concepts/auto6.C > new file mode 100644 > index 00000000000..1f6d72e54cc > --- /dev/null > +++ b/gcc/testsuite/g++.dg/concepts/auto6.C > @@ -0,0 +1,14 @@ > +// PR c++/101886 > +// { dg-do compile { target c++17_only } } > +// { dg-options "-fconcepts-ts" } > + > +template<typename, typename> struct A { }; > + > +template<class T> > +void f() { > + A<int, int> a; > + A<auto, auto> b1 = a; > + A<auto, auto> b2 = a; > +} > + > +template void f<int>(); > diff --git a/gcc/testsuite/g++.dg/concepts/diagnostic12.C b/gcc/testsuite/g++.dg/concepts/diagnostic12.C > index 548ba9c1b3d..8086500760b 100644 > --- a/gcc/testsuite/g++.dg/concepts/diagnostic12.C > +++ b/gcc/testsuite/g++.dg/concepts/diagnostic12.C > @@ -3,7 +3,7 @@ > > template<typename T, typename... Args> > concept c1 = requires (T t, Args... args) { *t; }; > -// { dg-message "in requirements with .T t., .Args ... args. .with Args = \{\}; T = int" "" { target *-*-* } .-1 } > +// { dg-message "in requirements with .T t., .Args ... args. .with T = int; Args = \{\}" "" { target *-*-* } .-1 } > > static_assert(c1<int>); // { dg-error "failed" } > > diff --git a/gcc/tree.cc b/gcc/tree.cc > index 0a51f9ddb4d..92199bb6503 100644 > --- a/gcc/tree.cc > +++ b/gcc/tree.cc > @@ -11310,12 +11310,12 @@ walk_tree_1 (tree *tp, walk_tree_fn func, void *data, > if (len == 0) > break; > > - /* Walk all elements but the first. */ > - while (--len) > - WALK_SUBTREE (TREE_VEC_ELT (*tp, len)); > + /* Walk all elements but the last. */ > + for (int i = 0; i < len - 1; ++i) > + WALK_SUBTREE (TREE_VEC_ELT (*tp, i)); > > - /* Now walk the first one as a tail call. */ > - WALK_SUBTREE_TAIL (TREE_VEC_ELT (*tp, 0)); > + /* Now walk the last one as a tail call. */ > + WALK_SUBTREE_TAIL (TREE_VEC_ELT (*tp, len - 1)); > } > > case VECTOR_CST: > @@ -11323,11 +11323,11 @@ walk_tree_1 (tree *tp, walk_tree_fn func, void *data, > unsigned len = vector_cst_encoded_nelts (*tp); > if (len == 0) > break; > - /* Walk all elements but the first. */ > - while (--len) > - WALK_SUBTREE (VECTOR_CST_ENCODED_ELT (*tp, len)); > - /* Now walk the first one as a tail call. */ > - WALK_SUBTREE_TAIL (VECTOR_CST_ENCODED_ELT (*tp, 0)); > + /* Walk all elements but the last. */ > + for (unsigned i = 0; i < len - 1; ++i) > + WALK_SUBTREE (VECTOR_CST_ENCODED_ELT (*tp, i)); > + /* Now walk the last one as a tail call. */ > + WALK_SUBTREE_TAIL (VECTOR_CST_ENCODED_ELT (*tp, len - 1)); > } > > case COMPLEX_CST:
diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc index 2b7b3756b68..df125a63785 100644 --- a/gcc/cp/pt.cc +++ b/gcc/cp/pt.cc @@ -10640,14 +10640,14 @@ for_each_template_parm (tree t, tree_fn_t fn, void* data, struct find_template_parameter_info { explicit find_template_parameter_info (tree ctx_parms) - : parm_list (NULL_TREE), - ctx_parms (ctx_parms), + : ctx_parms (ctx_parms), max_depth (TMPL_PARMS_DEPTH (ctx_parms)) {} hash_set<tree> visited; hash_set<tree> parms; - tree parm_list; + tree parm_list = NULL_TREE; + tree *parm_list_tail = &parm_list; tree ctx_parms; int max_depth; }; @@ -10693,7 +10693,12 @@ keep_template_parm (tree t, void* data) if (TYPE_P (t)) t = TYPE_MAIN_VARIANT (t); if (!ftpi->parms.add (t)) - ftpi->parm_list = tree_cons (NULL_TREE, t, ftpi->parm_list); + { + /* Append T to PARM_LIST. */ + tree node = build_tree_list (NULL_TREE, t); + *ftpi->parm_list_tail = node; + ftpi->parm_list_tail = &TREE_CHAIN (node); + } /* Verify the parameter we found has a valid index. */ if (flag_checking) diff --git a/gcc/testsuite/g++.dg/concepts/auto6.C b/gcc/testsuite/g++.dg/concepts/auto6.C new file mode 100644 index 00000000000..1f6d72e54cc --- /dev/null +++ b/gcc/testsuite/g++.dg/concepts/auto6.C @@ -0,0 +1,14 @@ +// PR c++/101886 +// { dg-do compile { target c++17_only } } +// { dg-options "-fconcepts-ts" } + +template<typename, typename> struct A { }; + +template<class T> +void f() { + A<int, int> a; + A<auto, auto> b1 = a; + A<auto, auto> b2 = a; +} + +template void f<int>(); diff --git a/gcc/testsuite/g++.dg/concepts/diagnostic12.C b/gcc/testsuite/g++.dg/concepts/diagnostic12.C index 548ba9c1b3d..8086500760b 100644 --- a/gcc/testsuite/g++.dg/concepts/diagnostic12.C +++ b/gcc/testsuite/g++.dg/concepts/diagnostic12.C @@ -3,7 +3,7 @@ template<typename T, typename... Args> concept c1 = requires (T t, Args... args) { *t; }; -// { dg-message "in requirements with .T t., .Args ... args. .with Args = \{\}; T = int" "" { target *-*-* } .-1 } +// { dg-message "in requirements with .T t., .Args ... args. .with T = int; Args = \{\}" "" { target *-*-* } .-1 } static_assert(c1<int>); // { dg-error "failed" } diff --git a/gcc/tree.cc b/gcc/tree.cc index 0a51f9ddb4d..92199bb6503 100644 --- a/gcc/tree.cc +++ b/gcc/tree.cc @@ -11310,12 +11310,12 @@ walk_tree_1 (tree *tp, walk_tree_fn func, void *data, if (len == 0) break; - /* Walk all elements but the first. */ - while (--len) - WALK_SUBTREE (TREE_VEC_ELT (*tp, len)); + /* Walk all elements but the last. */ + for (int i = 0; i < len - 1; ++i) + WALK_SUBTREE (TREE_VEC_ELT (*tp, i)); - /* Now walk the first one as a tail call. */ - WALK_SUBTREE_TAIL (TREE_VEC_ELT (*tp, 0)); + /* Now walk the last one as a tail call. */ + WALK_SUBTREE_TAIL (TREE_VEC_ELT (*tp, len - 1)); } case VECTOR_CST: @@ -11323,11 +11323,11 @@ walk_tree_1 (tree *tp, walk_tree_fn func, void *data, unsigned len = vector_cst_encoded_nelts (*tp); if (len == 0) break; - /* Walk all elements but the first. */ - while (--len) - WALK_SUBTREE (VECTOR_CST_ENCODED_ELT (*tp, len)); - /* Now walk the first one as a tail call. */ - WALK_SUBTREE_TAIL (VECTOR_CST_ENCODED_ELT (*tp, 0)); + /* Walk all elements but the last. */ + for (unsigned i = 0; i < len - 1; ++i) + WALK_SUBTREE (VECTOR_CST_ENCODED_ELT (*tp, i)); + /* Now walk the last one as a tail call. */ + WALK_SUBTREE_TAIL (VECTOR_CST_ENCODED_ELT (*tp, len - 1)); } case COMPLEX_CST: