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[2603:7000:9500:34a5::1db4]) by smtp.gmail.com with ESMTPSA id i2-20020a05620a074200b007676f3859fasm5869563qki.30.2023.09.07.08.23.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 07 Sep 2023 08:23:24 -0700 (PDT) Date: Thu, 7 Sep 2023 11:23:22 -0400 To: Jason Merrill Cc: GCC Patches Subject: [PATCH v2] c++: Move consteval folding to cp_fold_r Message-ID: References: <20230901172348.445289-1-polacek@redhat.com> MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/2.2.9 (2022-11-12) X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Disposition: inline X-Spam-Status: No, score=-12.4 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, KAM_SHORT, RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H4, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_NONE, TXREP, URI_HEX autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: gcc-patches@gcc.gnu.org X-Mailman-Version: 2.1.30 Precedence: list List-Id: Gcc-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Marek Polacek via Gcc-patches From: Marek Polacek Reply-To: Marek Polacek Errors-To: gcc-patches-bounces+ouuuleilei=gmail.com@gcc.gnu.org Sender: "Gcc-patches" X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1775856886258525196 X-GMAIL-MSGID: 1776393163134636725 On Tue, Sep 05, 2023 at 04:36:34PM -0400, Jason Merrill wrote: > On 9/5/23 15:59, Marek Polacek wrote: > > On Tue, Sep 05, 2023 at 10:52:04AM -0400, Jason Merrill wrote: > > > On 9/1/23 13:23, Marek Polacek wrote: > > > > Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk? > > > > > > > > -- >8 -- > > > > > > > > In the review of P2564: > > > > > > > > it turned out that in order to correctly handle an example in the paper, > > > > we should stop doing immediate evaluation in build_over_call and > > > > bot_replace, and instead do it in cp_fold_r. This patch does that. > > > > > > > > Another benefit is that this is a pretty significant simplification, at > > > > least in my opinion. Also, this fixes the c++/110997 ICE (but the test > > > > doesn't compile yet). > > > > > > > > The main drawback seems to be that cp_fold_r doesn't process as much > > > > code as we did before: uninstantiated templates > > > > > > That's acceptable, it's an optional diagnostic. > > > > > > > and things like "false ? foo () : 1". > > > > > > This is a problem. Maybe we want cp_fold_r to recurse into the arms of a > > > COND_EXPR before folding them away? Maybe only if we know we've seen an > > > immediate function? > > > > Unfortunately we had already thrown the dead branch away when we got to > > cp_fold_r. I wonder if we have to adjust cxx_eval_conditional_expression > > to call cp_fold_r on the dead branch too, > > Hmm, I guess so. > > > perhaps with a new ff_ flag to skip the whole second switch in cp_fold_r? > > Or factor out the immediate function handling to a separate walk function > that cp_fold_r also calls? I did that. > > But then it's possible that the in_immediate_context checks have to stay. > > We can just not do the walk in immediate (or mce_true) context, like we > currently avoid calling cp_fold_function. Right. Unfortunately I have to check even when mce_true, consider consteval int bar (int i) { if (i != 1) throw 1; return 0; } constexpr int a = 0 ? bar(3) : 3; > For mce_unknown I guess we'd want > to set *non_constant_p instead of giving an error. I did not do this because I haven't found a case where it would make a difference. > This is a problem. Maybe we want cp_fold_r to recurse into the arms of a > COND_EXPR before folding them away? Maybe only if we know we've seen an > immediate function? Hopefully resolved now. > > diff --git a/gcc/cp/constexpr.cc b/gcc/cp/constexpr.cc > > index 8bd5c4a47f8..af4f98b1fe1 100644 > > --- a/gcc/cp/constexpr.cc > > +++ b/gcc/cp/constexpr.cc > > @@ -3135,6 +3135,11 @@ cxx_eval_call_expression (const constexpr_ctx *ctx, tree t, > > unsigned save_heap_alloc_count = ctx->global->heap_vars.length (); > > unsigned save_heap_dealloc_count = ctx->global->heap_dealloc_count; > > + /* Make sure we fold std::is_constant_evaluated to true in an > > + immediate function. */ > > + if (immediate_invocation_p (fun)) > > I think this should just check DECL_IMMEDIATE_FUNCTION_P, the context > doesn't matter. Fixed. And now I don't need to export immediate_invocation_p. > > + call_ctx.manifestly_const_eval = mce_true; > > + > > diff --git a/gcc/cp/cp-gimplify.cc b/gcc/cp/cp-gimplify.cc > > index 206e791fcfd..29132aad158 100644 > > --- a/gcc/cp/cp-gimplify.cc > > +++ b/gcc/cp/cp-gimplify.cc > > @@ -1058,9 +1058,21 @@ cp_fold_r (tree *stmt_p, int *walk_subtrees, void *data_) > > } > > break; > > + /* Expand immediate invocations. */ > > + case CALL_EXPR: > > + case AGGR_INIT_EXPR: > > + if (!in_immediate_context ()) > > As you mentioned in your followup, we shouldn't need to check this because > we don't call cp_fold_r in immediate context. Fixed. > > + if (tree fn = cp_get_callee (stmt)) > > + if (TREE_CODE (fn) != ADDR_EXPR || ADDR_EXPR_DENOTES_CALL_P (fn)) > > + if (tree fndecl = cp_get_fndecl_from_callee (fn, /*fold*/false)) > > + if (DECL_IMMEDIATE_FUNCTION_P (fndecl)) > > + *stmt_p = stmt = cxx_constant_value (stmt); > > + break; > > + > > case ADDR_EXPR: > > if (TREE_CODE (TREE_OPERAND (stmt, 0)) == FUNCTION_DECL > > - && DECL_IMMEDIATE_FUNCTION_P (TREE_OPERAND (stmt, 0))) > > + && DECL_IMMEDIATE_FUNCTION_P (TREE_OPERAND (stmt, 0)) > > + && !in_immediate_context ()) > > Likewise. Fixed. > > diff --git a/gcc/cp/tree.cc b/gcc/cp/tree.cc > > index 799183dc646..7dfb6de2da3 100644 > > --- a/gcc/cp/tree.cc > > +++ b/gcc/cp/tree.cc > > @@ -3254,7 +3254,7 @@ bot_manip (tree* tp, int* walk_subtrees, void* data_) > > variables. */ > > static tree > > -bot_replace (tree* t, int* walk_subtrees, void* data_) > > +bot_replace (tree* t, int*, void* data_) > > Generally we keep the parameter name as a comment like > int */*walk_subtrees*/ I reaaally mislike that but ok, changed. > > diff --git a/gcc/testsuite/g++.dg/cpp23/consteval-if2.C b/gcc/testsuite/g++.dg/cpp23/consteval-if2.C > > index d1845da9e58..9fa95295c43 100644 > > --- a/gcc/testsuite/g++.dg/cpp23/consteval-if2.C > > +++ b/gcc/testsuite/g++.dg/cpp23/consteval-if2.C > > @@ -65,7 +65,7 @@ qux (int x) > > int r = 0; > > if not consteval // { dg-warning "'if consteval' only available with" "" { target c++20_only } } > > { > > - r += foo (x); // { dg-error "'x' is not a constant expression" } > > + r += foo (x); // { dg-error "'x' is not a constant expression" "" { xfail *-*-* } } > > This whole function should have a comment that these errors are not required > because qux is never instantiated. Added. > > diff --git a/gcc/testsuite/g++.dg/cpp2a/consteval11.C b/gcc/testsuite/g++.dg/cpp2a/consteval11.C > > index 2f68ec0f892..9fd32dcab7b 100644 > > --- a/gcc/testsuite/g++.dg/cpp2a/consteval11.C > > +++ b/gcc/testsuite/g++.dg/cpp2a/consteval11.C > > @@ -5,25 +5,25 @@ consteval int bar (int i) { if (i != 1) throw 1; return 0; } // { dg-error "is n > > constexpr int a = bar (1); > > constexpr int b = bar (2); // { dg-message "in 'constexpr' expansion of" } > > -constexpr int c = 0 ? bar (3) : 1; // { dg-message "in 'constexpr' expansion of" } > > +constexpr int c = 0 ? bar (3) : 1; > > As discussed above, we need to keep this diagnostic and the others like it. Should be fixed. > Let's also add a test with the > > template > constexpr bool is_not(T t, F f) { > return not f(t); > } > > consteval bool is_even(int i) { return i % 2 == 0; } > > static_assert(is_not(5, is_even)); // ok > > example from the paper. Added. I've also added consteval34.C which happened to crash clang++: https://github.com/llvm/llvm-project/issues/65520 Thanks. Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk? -- >8 -- In the review of P2564: it turned out that in order to correctly handle an example in the paper, we should stop doing immediate evaluation in build_over_call and bot_replace, and instead do it in cp_fold_r. This patch does that. Another benefit is that this is a pretty significant simplification, at least in my opinion. Also, this fixes the c++/110997 ICE (but the test doesn't compile yet). The main drawback seems to be that cp_fold_r doesn't process uninstantiated templates. We still have to handle things like "false ? foo () : 1". To that end, I've added cp_fold_immediate, called on dead branches in cxx_eval_conditional_expression. Since in cxx_* I can't rely on current_function_decl being available, I've added another walk: a new overload for in_immediate_context that looks into constexpr_ctx. You'll see that I've reintroduced ADDR_EXPR_DENOTES_CALL_P here. This is to detect *(&foo)) () (s.*&S::foo) () which were deemed ill-formed. gcc/cp/ChangeLog: * call.cc (in_immediate_context): No longer static. (build_over_call): Set ADDR_EXPR_DENOTES_CALL_P. Don't handle immediate_invocation_p here. * constexpr.cc (in_immediate_context): New overload. (cxx_eval_call_expression): Use mce_true for DECL_IMMEDIATE_FUNCTION_P. (cxx_eval_conditional_expression): Call cp_fold_immediate. * cp-gimplify.cc (maybe_replace_decl): Make static. (cp_fold_r): Expand immediate invocations. (cp_fold_immediate_r): New. (cp_fold_immediate): New. * cp-tree.h (ADDR_EXPR_DENOTES_CALL_P): Define. (cp_fold_immediate): Declare. * tree.cc (bot_replace): Don't handle immediate invocations here. libstdc++-v3/ChangeLog: * testsuite/20_util/allocator/105975.cc: Add dg-error. gcc/testsuite/ChangeLog: * g++.dg/cpp23/consteval-if2.C: Add xfail. * g++.dg/cpp2a/consteval-memfn1.C: Adjust. * g++.dg/cpp2a/consteval11.C: Remove dg-message. * g++.dg/cpp2a/consteval3.C: Remove dg-message and dg-error. * g++.dg/cpp2a/consteval9.C: Remove dg-message. * g++.dg/cpp2a/consteval32.C: New test. * g++.dg/cpp2a/consteval33.C: New test. * g++.dg/cpp2a/consteval34.C: New test. * g++.dg/cpp2a/consteval35.C: New test. --- gcc/cp/call.cc | 40 ++-------- gcc/cp/constexpr.cc | 38 ++++++++- gcc/cp/cp-gimplify.cc | 79 +++++++++++++++---- gcc/cp/cp-tree.h | 6 ++ gcc/cp/tree.cc | 23 +----- gcc/testsuite/g++.dg/cpp23/consteval-if2.C | 3 +- gcc/testsuite/g++.dg/cpp2a/consteval-memfn1.C | 7 ++ gcc/testsuite/g++.dg/cpp2a/consteval11.C | 23 +++--- gcc/testsuite/g++.dg/cpp2a/consteval3.C | 3 +- gcc/testsuite/g++.dg/cpp2a/consteval32.C | 4 + gcc/testsuite/g++.dg/cpp2a/consteval33.C | 34 ++++++++ gcc/testsuite/g++.dg/cpp2a/consteval34.C | 18 +++++ gcc/testsuite/g++.dg/cpp2a/consteval35.C | 10 +++ gcc/testsuite/g++.dg/cpp2a/consteval9.C | 3 +- .../testsuite/20_util/allocator/105975.cc | 2 +- 15 files changed, 203 insertions(+), 90 deletions(-) create mode 100644 gcc/testsuite/g++.dg/cpp2a/consteval32.C create mode 100644 gcc/testsuite/g++.dg/cpp2a/consteval33.C create mode 100644 gcc/testsuite/g++.dg/cpp2a/consteval34.C create mode 100644 gcc/testsuite/g++.dg/cpp2a/consteval35.C base-commit: 971f119f0832cd1f3042d73a11f5a1be2361fc3f diff --git a/gcc/cp/call.cc b/gcc/cp/call.cc index 399345307ea..1b99967e4cf 100644 --- a/gcc/cp/call.cc +++ b/gcc/cp/call.cc @@ -10436,6 +10436,10 @@ build_over_call (struct z_candidate *cand, int flags, tsubst_flags_t complain) fn = build_addr_func (fn, complain); if (fn == error_mark_node) return error_mark_node; + + /* We're actually invoking the function. (Immediate functions get an + & when invoking it even though the user didn't use &.) */ + ADDR_EXPR_DENOTES_CALL_P (fn) = true; } tree call = build_cxx_call (fn, nargs, argarray, complain|decltype_flag); @@ -10453,41 +10457,7 @@ build_over_call (struct z_candidate *cand, int flags, tsubst_flags_t complain) if (TREE_CODE (c) == CALL_EXPR) suppress_warning (c /* Suppress all warnings. */); } - if (TREE_CODE (fn) == ADDR_EXPR) - { - tree fndecl = STRIP_TEMPLATE (TREE_OPERAND (fn, 0)); - if (immediate_invocation_p (fndecl)) - { - tree obj_arg = NULL_TREE; - /* Undo convert_from_reference called by build_cxx_call. */ - if (REFERENCE_REF_P (call)) - call = TREE_OPERAND (call, 0); - if (DECL_CONSTRUCTOR_P (fndecl)) - obj_arg = cand->first_arg ? cand->first_arg : (*args)[0]; - if (obj_arg && is_dummy_object (obj_arg)) - { - call = build_cplus_new (DECL_CONTEXT (fndecl), call, complain); - obj_arg = NULL_TREE; - } - /* Look through *(const T *)&obj. */ - else if (obj_arg && INDIRECT_REF_P (obj_arg)) - { - tree addr = TREE_OPERAND (obj_arg, 0); - STRIP_NOPS (addr); - if (TREE_CODE (addr) == ADDR_EXPR) - { - tree typeo = TREE_TYPE (obj_arg); - tree typei = TREE_TYPE (TREE_OPERAND (addr, 0)); - if (same_type_ignoring_top_level_qualifiers_p (typeo, typei)) - obj_arg = TREE_OPERAND (addr, 0); - } - } - call = cxx_constant_value (call, obj_arg, complain); - if (obj_arg && !error_operand_p (call)) - call = cp_build_init_expr (obj_arg, call); - call = convert_from_reference (call); - } - } + return call; } diff --git a/gcc/cp/constexpr.cc b/gcc/cp/constexpr.cc index 0ca4370deab..397d5c7ec3f 100644 --- a/gcc/cp/constexpr.cc +++ b/gcc/cp/constexpr.cc @@ -2311,6 +2311,29 @@ cxx_dynamic_cast_fn_p (tree fndecl) && CP_DECL_CONTEXT (fndecl) == abi_node); } +/* Return true if we are in the body of a consteval function. + This is in addition to in_immediate_context because that + uses current_function_decl which may not be available. CTX is + the current constexpr context. */ + +static bool +in_immediate_context (const constexpr_ctx *ctx) +{ + if (in_immediate_context ()) + return true; + + while (ctx) + { + if (ctx->call + && ctx->call->fundef + && DECL_IMMEDIATE_FUNCTION_P (ctx->call->fundef->decl)) + return true; + ctx = ctx->parent; + } + + return false; +} + /* Often, we have an expression in the form of address + offset, e.g. "&_ZTV1A + 16". Extract the object from it, i.e. "_ZTV1A". */ @@ -3135,6 +3158,11 @@ cxx_eval_call_expression (const constexpr_ctx *ctx, tree t, unsigned save_heap_alloc_count = ctx->global->heap_vars.length (); unsigned save_heap_dealloc_count = ctx->global->heap_dealloc_count; + /* Make sure we fold std::is_constant_evaluated to true in an + immediate function. */ + if (DECL_IMMEDIATE_FUNCTION_P (fun)) + call_ctx.manifestly_const_eval = mce_true; + /* If this is a constexpr destructor, the object's const and volatile semantics are no longer in effect; see [class.dtor]p5. */ if (new_obj && DECL_DESTRUCTOR_P (fun)) @@ -3807,8 +3835,7 @@ cxx_eval_binary_expression (const constexpr_ctx *ctx, tree t, } /* Subroutine of cxx_eval_constant_expression. - Attempt to evaluate condition expressions. Dead branches are not - looked into. */ + Attempt to evaluate condition expressions. */ static tree cxx_eval_conditional_expression (const constexpr_ctx *ctx, tree t, @@ -3837,12 +3864,17 @@ cxx_eval_conditional_expression (const constexpr_ctx *ctx, tree t, boolean_type_node); } /* Don't VERIFY_CONSTANT the other operands. */ - if (integer_zerop (val)) + const bool zero_p = integer_zerop (val); + if (zero_p) val = TREE_OPERAND (t, 2); else val = TREE_OPERAND (t, 1); if (TREE_CODE (t) == IF_STMT && !val) val = void_node; + + if (!in_immediate_context (ctx)) + cp_fold_immediate (&TREE_OPERAND (t, zero_p ? 1 : 2)); + /* A TARGET_EXPR may be nested inside another TARGET_EXPR, but still serve as the initializer for the same object as the outer TARGET_EXPR, as in diff --git a/gcc/cp/cp-gimplify.cc b/gcc/cp/cp-gimplify.cc index 206e791fcfd..266bc50b68b 100644 --- a/gcc/cp/cp-gimplify.cc +++ b/gcc/cp/cp-gimplify.cc @@ -1000,7 +1000,7 @@ cp_genericize_target_expr (tree *stmt_p) replacement when cp_folding TARGET_EXPR to preserve the invariant that AGGR_INIT_EXPR_SLOT agrees with the enclosing TARGET_EXPR_SLOT. */ -bool +static bool maybe_replace_decl (tree *tp, tree decl, tree replacement) { if (!*tp || !VOID_TYPE_P (TREE_TYPE (*tp))) @@ -1029,22 +1029,33 @@ struct cp_genericize_data bool handle_invisiref_parm_p; }; -/* Perform any pre-gimplification folding of C++ front end trees to - GENERIC. - Note: The folding of non-omp cases is something to move into - the middle-end. As for now we have most foldings only on GENERIC - in fold-const, we need to perform this before transformation to - GIMPLE-form. */ +/* A subroutine of cp_fold_r to handle immediate functions. */ static tree -cp_fold_r (tree *stmt_p, int *walk_subtrees, void *data_) +cp_fold_immediate_r (tree *stmt_p, int *walk_subtrees, void *data_) { - cp_fold_data *data = (cp_fold_data*)data_; + auto data = static_cast(data_); tree stmt = *stmt_p; - enum tree_code code = TREE_CODE (stmt); - switch (code) + /* No need to look into types or unevaluated operands. + NB: This affects cp_fold_r as well. */ + if (TYPE_P (stmt) || unevaluated_p (TREE_CODE (stmt))) { + *walk_subtrees = 0; + return NULL_TREE; + } + + switch (TREE_CODE (stmt)) + { + /* Unfortunately we must handle code like + false ? bar () : 42 + where we have to check bar too. */ + case COND_EXPR: + cp_fold_immediate_r (&TREE_OPERAND (stmt, 1), walk_subtrees, data); + if (TREE_OPERAND (stmt, 2)) + cp_fold_immediate_r (&TREE_OPERAND (stmt, 2), walk_subtrees, data); + break; + case PTRMEM_CST: if (TREE_CODE (PTRMEM_CST_MEMBER (stmt)) == FUNCTION_DECL && DECL_IMMEDIATE_FUNCTION_P (PTRMEM_CST_MEMBER (stmt))) @@ -1058,6 +1069,16 @@ cp_fold_r (tree *stmt_p, int *walk_subtrees, void *data_) } break; + /* Expand immediate invocations. */ + case CALL_EXPR: + case AGGR_INIT_EXPR: + if (tree fn = cp_get_callee (stmt)) + if (TREE_CODE (fn) != ADDR_EXPR || ADDR_EXPR_DENOTES_CALL_P (fn)) + if (tree fndecl = cp_get_fndecl_from_callee (fn, /*fold*/false)) + if (DECL_IMMEDIATE_FUNCTION_P (fndecl)) + *stmt_p = stmt = cxx_constant_value (stmt); + break; + case ADDR_EXPR: if (TREE_CODE (TREE_OPERAND (stmt, 0)) == FUNCTION_DECL && DECL_IMMEDIATE_FUNCTION_P (TREE_OPERAND (stmt, 0))) @@ -1074,6 +1095,34 @@ cp_fold_r (tree *stmt_p, int *walk_subtrees, void *data_) break; } + return NULL_TREE; +} + +/* A wrapper around cp_fold_immediate_r. */ + +void +cp_fold_immediate (tree *tp) +{ + cp_fold_data data (ff_mce_false); + cp_walk_tree (tp, cp_fold_immediate_r, &data, nullptr); +} + +/* Perform any pre-gimplification folding of C++ front end trees to + GENERIC. + Note: The folding of non-omp cases is something to move into + the middle-end. As for now we have most foldings only on GENERIC + in fold-const, we need to perform this before transformation to + GIMPLE-form. */ + +static tree +cp_fold_r (tree *stmt_p, int *walk_subtrees, void *data_) +{ + cp_fold_data *data = (cp_fold_data*)data_; + tree stmt = *stmt_p; + enum tree_code code = TREE_CODE (stmt); + + cp_fold_immediate_r (stmt_p, walk_subtrees, data); + *stmt_p = stmt = cp_fold (*stmt_p, data->flags); if (data->pset.add (stmt)) @@ -1084,7 +1133,7 @@ cp_fold_r (tree *stmt_p, int *walk_subtrees, void *data_) always the same tree, which the first time cp_fold_r has been called on it had the subtrees walked. */ *walk_subtrees = 0; - return NULL; + return NULL_TREE; } code = TREE_CODE (stmt); @@ -1136,7 +1185,7 @@ cp_fold_r (tree *stmt_p, int *walk_subtrees, void *data_) } cp_walk_tree (&OMP_FOR_PRE_BODY (stmt), cp_fold_r, data, NULL); *walk_subtrees = 0; - return NULL; + return NULL_TREE; case IF_STMT: if (IF_STMT_CONSTEVAL_P (stmt)) @@ -1146,7 +1195,7 @@ cp_fold_r (tree *stmt_p, int *walk_subtrees, void *data_) cp_walk_tree (&ELSE_CLAUSE (stmt), cp_fold_r, data, NULL); cp_walk_tree (&IF_SCOPE (stmt), cp_fold_r, data, NULL); *walk_subtrees = 0; - return NULL; + return NULL_TREE; } break; @@ -1183,7 +1232,7 @@ cp_fold_r (tree *stmt_p, int *walk_subtrees, void *data_) break; } - return NULL; + return NULL_TREE; } /* Fold ALL the trees! FIXME we should be able to remove this, but diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h index 3ca011c61c8..dc3efc8a472 100644 --- a/gcc/cp/cp-tree.h +++ b/gcc/cp/cp-tree.h @@ -4784,6 +4784,11 @@ get_vec_init_expr (tree t) #define PTRMEM_OK_P(NODE) \ TREE_LANG_FLAG_0 (TREE_CHECK3 ((NODE), ADDR_EXPR, OFFSET_REF, SCOPE_REF)) +/* True if this ADDR_EXPR denotes a function call; that is, it's + fn() rather than &fn. */ +#define ADDR_EXPR_DENOTES_CALL_P(NODE) \ + (ADDR_EXPR_CHECK(NODE)->base.protected_flag) + /* Get the POINTER_TYPE to the METHOD_TYPE associated with this pointer to member function. TYPE_PTRMEMFUNC_P _must_ be true, before using this macro. */ @@ -8354,6 +8359,7 @@ extern tree process_stmt_assume_attribute (tree, tree, location_t); extern bool simple_empty_class_p (tree, tree, tree_code); extern tree fold_builtin_source_location (const_tree); extern tree get_source_location_impl_type (); +extern void cp_fold_immediate (tree *); /* in name-lookup.cc */ extern tree strip_using_decl (tree); diff --git a/gcc/cp/tree.cc b/gcc/cp/tree.cc index 799183dc646..eaf882f8854 100644 --- a/gcc/cp/tree.cc +++ b/gcc/cp/tree.cc @@ -3254,7 +3254,7 @@ bot_manip (tree* tp, int* walk_subtrees, void* data_) variables. */ static tree -bot_replace (tree* t, int* walk_subtrees, void* data_) +bot_replace (tree* t, int */*walk_subtrees*/, void* data_) { bot_data &data = *(bot_data*)data_; splay_tree target_remap = data.target_remap; @@ -3284,27 +3284,6 @@ bot_replace (tree* t, int* walk_subtrees, void* data_) /*check_access=*/false, /*nonnull=*/true, tf_warning_or_error); } - else if (cxx_dialect >= cxx20 - && (TREE_CODE (*t) == CALL_EXPR - || TREE_CODE (*t) == AGGR_INIT_EXPR) - && !in_immediate_context ()) - { - /* Expand immediate invocations. */ - if (tree fndecl = cp_get_callee_fndecl_nofold (*t)) - if (DECL_IMMEDIATE_FUNCTION_P (fndecl)) - { - /* Make in_immediate_context true within the args. */ - in_consteval_if_p_temp_override ito; - in_consteval_if_p = true; - int nargs = call_expr_nargs (*t); - for (int i = 0; i < nargs; ++i) - cp_walk_tree (&get_nth_callarg (*t, i), bot_replace, data_, NULL); - *t = cxx_constant_value (*t); - if (*t == error_mark_node) - return error_mark_node; - *walk_subtrees = 0; - } - } return NULL_TREE; } diff --git a/gcc/testsuite/g++.dg/cpp23/consteval-if2.C b/gcc/testsuite/g++.dg/cpp23/consteval-if2.C index d1845da9e58..b2c5472b7de 100644 --- a/gcc/testsuite/g++.dg/cpp23/consteval-if2.C +++ b/gcc/testsuite/g++.dg/cpp23/consteval-if2.C @@ -58,6 +58,7 @@ baz (int x) return r; } +// This function is not instantiated so NDR. template constexpr int qux (int x) @@ -65,7 +66,7 @@ qux (int x) int r = 0; if not consteval // { dg-warning "'if consteval' only available with" "" { target c++20_only } } { - r += foo (x); // { dg-error "'x' is not a constant expression" } + r += foo (x); // { dg-error "'x' is not a constant expression" "" { xfail *-*-* } } } else { diff --git a/gcc/testsuite/g++.dg/cpp2a/consteval-memfn1.C b/gcc/testsuite/g++.dg/cpp2a/consteval-memfn1.C index 910e7a1ac1e..63f4f1d526a 100644 --- a/gcc/testsuite/g++.dg/cpp2a/consteval-memfn1.C +++ b/gcc/testsuite/g++.dg/cpp2a/consteval-memfn1.C @@ -25,3 +25,10 @@ void VerifyHash(fixed_string s) { fixed_string::size_static(-1); // { dg-message "expansion of" } s(); // { dg-bogus "" } } + +void +do_test () +{ + fixed_string f; + VerifyHash(f); +} diff --git a/gcc/testsuite/g++.dg/cpp2a/consteval11.C b/gcc/testsuite/g++.dg/cpp2a/consteval11.C index 2f68ec0f892..94b26cd85c4 100644 --- a/gcc/testsuite/g++.dg/cpp2a/consteval11.C +++ b/gcc/testsuite/g++.dg/cpp2a/consteval11.C @@ -33,13 +33,13 @@ foo () else bar (12); // { dg-message "in 'constexpr' expansion of" } if constexpr (0) - bar (13); // { dg-message "in 'constexpr' expansion of" } + bar (13); else bar (14); // { dg-message "in 'constexpr' expansion of" } if constexpr (1) bar (15); // { dg-message "in 'constexpr' expansion of" } else - bar (16); // { dg-message "in 'constexpr' expansion of" } + bar (16); } consteval int @@ -77,22 +77,25 @@ template void qux () { + // Used to give errors errors here, but not since we moved consteval + // function folding to cp_fold_r which isn't called on uninstantiated + // templates. if (0) - bar (2); // { dg-message "in 'constexpr' expansion of" } + bar (2); else - bar (3); // { dg-message "in 'constexpr' expansion of" } + bar (3); if (1) - bar (4); // { dg-message "in 'constexpr' expansion of" } + bar (4); else - bar (5); // { dg-message "in 'constexpr' expansion of" } + bar (5); if constexpr (0) - bar (6); // { dg-message "in 'constexpr' expansion of" } + bar (6); else - bar (7); // { dg-message "in 'constexpr' expansion of" } + bar (7); if constexpr (1) - bar (8); // { dg-message "in 'constexpr' expansion of" } + bar (8); else - bar (9); // { dg-message "in 'constexpr' expansion of" } + bar (9); if (0) bar ((T) 2); else diff --git a/gcc/testsuite/g++.dg/cpp2a/consteval3.C b/gcc/testsuite/g++.dg/cpp2a/consteval3.C index 627ab142d5a..9efac8c8eae 100644 --- a/gcc/testsuite/g++.dg/cpp2a/consteval3.C +++ b/gcc/testsuite/g++.dg/cpp2a/consteval3.C @@ -18,8 +18,7 @@ consteval int f6 (int x) { return x; } int d = 6; // { dg-message "'int d' is not const" } int e = f6 (d); // { dg-error "the value of 'd' is not usable in a constant expression" } constexpr int f7 (int x) { return f6 (x); } // { dg-error "'x' is not a constant expression" } -constexpr int f = f7 (5); // { dg-error "" } - // { dg-message "in 'constexpr' expansion of" "" { target *-*-* } .-1 } +constexpr int f = f7 (5); using fnptr = int (int); fnptr *g = f6; // { dg-error "taking address of an immediate function 'consteval int f6\\(int\\)'" } int f8 (fnptr *); diff --git a/gcc/testsuite/g++.dg/cpp2a/consteval32.C b/gcc/testsuite/g++.dg/cpp2a/consteval32.C new file mode 100644 index 00000000000..f1de63e41b9 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp2a/consteval32.C @@ -0,0 +1,4 @@ +// { dg-do compile { target c++20 } } + +consteval int foo () { return 42; } +int bar () { return (*(&foo)) (); } // { dg-error "taking address" } diff --git a/gcc/testsuite/g++.dg/cpp2a/consteval33.C b/gcc/testsuite/g++.dg/cpp2a/consteval33.C new file mode 100644 index 00000000000..3d50b00c7a3 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp2a/consteval33.C @@ -0,0 +1,34 @@ +// { dg-do compile { target c++20 } } + +consteval int id (int i) { return i; } +consteval int add (int i, int j) { return i + j; } + +constexpr int +foo (int i = id (42)) +{ + return i + id (id (id (0))); +} + +constexpr int +bar (int i = id (id (id (42)))) +{ + return i; +} + +constexpr int +baz (int i = add (add (id (1), id (2)), id (3))) +{ + return i; +} + +void +g () +{ + foo (); + bar (); + baz (); +} + +static_assert (foo () == 42); +static_assert (bar () == 42); +static_assert (baz () == 6); diff --git a/gcc/testsuite/g++.dg/cpp2a/consteval34.C b/gcc/testsuite/g++.dg/cpp2a/consteval34.C new file mode 100644 index 00000000000..022eb4e76aa --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp2a/consteval34.C @@ -0,0 +1,18 @@ +// { dg-do compile { target c++20 } } + +consteval int bar (int i) { if (i != 1) throw 1; return 0; } // { dg-error "is not a constant expression" } + +constexpr int +foo (bool b) +{ + return b ? bar (3) : 2; // { dg-message "in .constexpr. expansion" } +} + +static_assert (foo (false) == 2); + +void +g () +{ + __extension__ int a1[bar(3)]; // { dg-message "in .constexpr. expansion" } + int a2[sizeof (bar(3))]; +} diff --git a/gcc/testsuite/g++.dg/cpp2a/consteval35.C b/gcc/testsuite/g++.dg/cpp2a/consteval35.C new file mode 100644 index 00000000000..59d23ac482b --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp2a/consteval35.C @@ -0,0 +1,10 @@ +// { dg-do compile { target c++20 } } + +template +constexpr bool is_not(T t, F f) { + return not f(t); +} + +consteval bool is_even(int i) { return i % 2 == 0; } + +static_assert(is_not(5, is_even)); // ok diff --git a/gcc/testsuite/g++.dg/cpp2a/consteval9.C b/gcc/testsuite/g++.dg/cpp2a/consteval9.C index 489286a12d2..aa75ba37849 100644 --- a/gcc/testsuite/g++.dg/cpp2a/consteval9.C +++ b/gcc/testsuite/g++.dg/cpp2a/consteval9.C @@ -15,10 +15,11 @@ void qux () int a = bar (N); // { dg-message "in 'constexpr' expansion of 'bar\\(2\\)'" } } +// This function is not instantiated so NDR. template void quux () { - int a = bar (5); // { dg-message "in 'constexpr' expansion of 'bar\\(5\\)'" } + int a = bar (5); } void diff --git a/libstdc++-v3/testsuite/20_util/allocator/105975.cc b/libstdc++-v3/testsuite/20_util/allocator/105975.cc index 09f27ba86e3..06f1d96d9b7 100644 --- a/libstdc++-v3/testsuite/20_util/allocator/105975.cc +++ b/libstdc++-v3/testsuite/20_util/allocator/105975.cc @@ -14,6 +14,6 @@ consteval bool test_pr105957() a.deallocate(p, n); return true; } -static_assert( test_pr105957() ); +static_assert( test_pr105957() ); // { dg-error "non-constant" } // { dg-error "throw_bad_array_new_length" "" { target *-*-* } 0 }