This documents new GCC 10 behavior on diagnostic options and -flto.

2020-05-22  Richard Biener  <rguenther@suse.de>

	PR lto/95190
	* doc/invoke.texi (flto): Document behavior of diagnostic
	options.

This tries to enforce a set SLP_TREE_VECTYPE in vect_get_constant_vectors
and provides some infrastructure for setting it in the vectorizable_*
functions, amending those.

2020-05-22  Richard Biener  <rguenther@suse.de>

	* tree-vectorizer.h (vect_is_simple_use): New overload.
	(vect_maybe_update_slp_op_vectype): New.
	* tree-vect-stmts.c (vect_is_simple_use): New overload
	accessing operands of SLP vs. non-SLP operation transparently.
	(vect_maybe_update_slp_op_vectype): New function updating
	the possibly shared SLP operands vector type.
	(vectorizable_operation): Be a bit more SLP vs non-SLP agnostic
	using the new vect_is_simple_use overload;  update SLP invariant
	operand nodes vector type.
	(vectorizable_comparison): Likewise.
	(vectorizable_call): Likewise.
	(vectorizable_conversion): Likewise.
	(vectorizable_shift): Likewise.
	(vectorizable_store): Likewise.
	(vectorizable_condition): Likewise.
	(vectorizable_assignment): Likewise.
	* tree-vect-loop.c (vectorizable_reduction): Likewise.
	* tree-vect-slp.c (vect_get_constant_vectors): Enforce
	present SLP_TREE_VECTYPE and check it matches previous
	behavior.

This fixes a leftover early out in determining the sequence of stores
to materialize.

2020-05-22  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/95248
	* tree-ssa-loop-im.c (sm_seq_valid_bb): Remove bogus early out.

	* gcc.dg/torture/pr95248.c: New testcase.

This adds constructor and destructor to slp_tree factoring common
code.  I've not changed the wrappers to overloaded CTORs since
I hope to use object_allocator<> and am not sure whether that can
be done in any fancy way yet.

2020-05-22  Richard Biener  <rguenther@suse.de>

	* tree-vectorizer.h (_slp_tree::_slp_tree): New.
	(_slp_tree::~_slp_tree): Likewise.
	* tree-vect-slp.c (_slp_tree::_slp_tree): Factor out code
	from allocators.
	(_slp_tree::~_slp_tree): Implement.
	(vect_free_slp_tree): Simplify.
	(vect_create_new_slp_node): Likewise.  Add nops parameter.
	(vect_build_slp_tree_2): Adjust.
	(vect_analyze_slp_instance): Likewise.

contrib/ChangeLog:

2020-05-22  Martin Liska  <mliska@suse.cz>

	* gcc-changelog/git_commit.py: Add gcc/testsuite/go.test/test
	to ignored locations.

We give a better diagnostic for non-constant array bounds in
compute_array_index_type_loc, we don't need to diagnose it in the parser.
But to avoid a regression on parse/varmod1.C we need to actually check
non-dependent expressions in a template.

gcc/cp/ChangeLog:

	* decl.c (compute_array_index_type_loc): Diagnose expressions
	in a template that can't be constant.
	* parser.c (cp_parser_direct_declarator): Don't check
	non-constant array bounds here.

gcc/testsuite/ChangeLog:

	* c-c++-common/gomp/depend-iterator-2.c: Adjust.
	* g++.dg/ext/vla1.C: Adjust.
	* g++.dg/template/array9.C: Adjust.
	* g++.dg/template/error41.C: Adjust.

The difference between a "potential" constant-expression and a regular
constant-expression is the treatment of parameters; in a constexpr function,
a parameter is potentially constant when evaluating a call to that function,
but it is not constant during parsing of the function.
cp_parser_constant_expression should check the latter rather than the
former.

gcc/cp/ChangeLog:

	* cp-tree.h (is_rvalue_constant_expression): Declare.
	* constexpr.c (is_rvalue_constant_expression): New.
	* parser.c (cp_parser_constant_expression): Use it.
	* decl.c (cp_finish_decl): Try to treat a constexpr initializer in a
	template as constant.

In a template we were happily embedding error_mark_node in a MODOP_EXPR,
leading to confusion later.

gcc/cp/ChangeLog:

	* typeck.c (build_x_modify_expr): Handle error_mark_node arguments.

gcc/testsuite/ChangeLog:

	* g++.dg/cpp0x/lambda/lambda-ice30.C: Adjust.
	* g++.dg/cpp0x/lambda/lambda-ice31.C: Adjust.
	* g++.dg/ext/fixed1.C: Adjust.
	* g++.dg/template/crash107.C: Adjust.
	* g++.dg/template/error35.C: Adjust.
	* g++.dg/template/sizeof-template-argument.C: Adjust.

If a parameter is erroneous, we currently drop it, leading to "too many
arguments" errors later.  Treating the function as (...) avoids those
errors.

gcc/cp/ChangeLog:

	* decl.c (grokparms): Return NULL_TREE if any parms were erroneous.

gcc/testsuite/ChangeLog:

	* g++.dg/parse/error33.C: Adjust.

co_returns are statements, not expressions; they do not need
to be wrapped in an EXPR_STMT.

gcc/cp/ChangeLog:

	* coroutines.cc (finish_co_return_stmt): Revert change to use
	finish_expr_stmt.

Commit dfa4fcdb broke SPARC bootstrap:

In file included from ./tm_p.h:4,
                 from /vol/gcc/src/hg/master/local/gcc/adjust-alignment.c:28:
/vol/gcc/src/hg/master/local/gcc/config/sparc/sparc-protos.h:45:47: error: use of enum 'memmodel' without previous declaration
 extern void sparc_emit_membar_for_model (enum memmodel, int, int);
                                               ^~~~~~~~

Fixed by including memmodel.h.  Bootstrapped on sparc-sun-solaris2.11
and i386-pc-solaris2.11.

2020-05-21  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>

	gcc/
	* adjust-alignment.c: Include memmodel.h.

Since Intel SDM uses hexadecimal, use hexadecimal in comments.

	PR target/95260
	* config/i386/cpuid.h: Use hexadecimal in comments.

2020-05-21  Matthias Kretz  <kretz@kde.org>

	* testsuite/Makefile.am: Remove dup target_triplet and set tool,
	allowing runtest to work without arguments.
	* testsuite/Makefile.in: Regenerate.

Signed-off-by: Jonathan Wakely <jwakely@redhat.com>

Unfortunately, the previous fix to PR94038 is fragile.  When the
argument to fold_for_warn is a bare CALL_EXPR, then all is well: the
result of maybe_constant_value from fold_for_warn (with
uid_sensitive=true) is reused via the cv_cache in the subsequent call to
maybe_constant_value from cp_fold (with uid_sensitive=false), so we
avoid instantiating bar<int>.

But when the argument to fold_for_warn is more complex, e.g. an
INDIRECT_REF of a CALL_EXPR, as in the testcase below (due to bar<int>()
returning const int& which we need to decay to int) then from
fold_for_warn we call maybe_constant_value on the INDIRECT_REF, and from
cp_fold we call it on the CALL_EXPR, so there is no reuse via the
cv_cache and we therefore end up instantiating bar<int>.

So for a more robust solution to this general issue of warning flags
affecting code generation, it seems that we need a way to globally avoid
template instantiation during constexpr evaluation whenever we're
performing warning-dependent folding.

To that end, this patch replaces the flag constexpr_ctx::uid_sensitive
with a global flag uid_sensitive_constexpr_evaluation_p, and enables it
during fold_for_warn using an RAII helper.

The patch also adds a counter that keeps track of the number of times
uid_sensitive_constexpr_evaluation_p is called and returned true, and we
use this to determine whether the result of constexpr evaluation
was restricted by the flag.  This lets us safely update the cv_cache and
fold_cache from fold_for_warn in the most common case where the flag
did not restrict constexpr evaluation.

gcc/cp/ChangeLog:

	PR c++/94038
	* constexpr.c (constexpr_ctx::uid_sensitive): Remove field.
	(uid_sensitive_constexpr_evaluation_value): Define.
	(uid_sensitive_constexpr_evaluation_true_counter): Define.
	(uid_sensitive_constexpr_evaluation_p): Define.
	(uid_sensitive_constexpr_evaluation_sentinel): Define its
	constructor.
	(uid_sensitive_constexpr_evaluation_checker): Define its
	constructor and its evaluation_restricted_p method.
	(get_fundef_copy): Remove 'ctx' parameter.  Use u_s_c_e_p
	instead of constexpr_ctx::uid_sensitive.
	(cxx_eval_call_expression): Use u_s_c_e_p instead, and test it
	last.  Adjust call to get_fundef_copy.
	(instantiate_cx_fn_r): Test u_s_c_e_p so that we increment the
	counter if necessary.
	(cxx_eval_outermost_constant_expr): Remove 'uid_sensitive'
	parameter.  Adjust function body accordingly.
	(maybe_constant_value): Remove 'uid_sensitive' parameter and
	adjust function body accordingly.  Set up a
	uid_sensitive_constexpr_evaluation_checker, and use it to
	conditionally update the cv_cache.
	* cp-gimplify.c (cp_fold): Set up a
	uid_sensitive_constexpr_evaluation_checker, and use it to
	conditionally update the fold_cache.
	* cp-tree.h (maybe_constant_value): Update declaration.
	(struct uid_sensitive_constexpr_evaluation_sentinel): Define.
	(struct sensitive_constexpr_evaluation_checker): Define.
	* expr.c (fold_for_warn): Set up a
	uid_sensitive_constexpr_evaluation_sentinel before calling
	the folding subroutines.  Drop all but the first argument to
	maybe_constant_value.

gcc/testsuite/ChangeLog:

	PR c++/94038
	* g++.dg/warn/pr94038-2.C: New test.

Move FEATURE_AVX512VP2INTERSECT after FEATURE_AVX512BF16 to avoid
changing libgcc ABI.

gcc/

	PR target/95212
	* config/i386/i386-builtins.c (processor_features): Move
	F_AVX512VP2INTERSECT after F_AVX512BF16.
	(isa_names_table): Likewise.

libgcc/

	PR target/95212
	* config/i386/cpuinfo.h (processor_features): Move
	FEATURE_AVX512VP2INTERSECT after FEATURE_AVX512BF16.

	PR target/95229
	* g++.target/i386/pr95229.C: Fix
	error: unnamed type with no linkage used
	to declare variable ‘<unnamed class> e’ with linkage
	with -std=gnu++98.

	* c-c++-common/cpp/cmd-1.c: Delete.
	* c-c++-common/cpp/cmd-1.h: Delete.

	* m4/matmul.m4: Don't include <config/i386/cpuinfo.h>.  Use
	__builtin_cpu_is/__builtin_cpu_supports
	* generated/matmul_c10.c: Regenerated.
	* generated/matmul_c16.c: Likewise.
	* generated/matmul_c4.c: Likewise.
	* generated/matmul_c8.c: Likewise.
	* generated/matmul_i1.c: Likewise.
	* generated/matmul_i16.c: Likewise.
	* generated/matmul_i2.c: Likewise.
	* generated/matmul_i4.c: Likewise.
	* generated/matmul_i8.c: Likewise.
	* generated/matmul_r10.c: Likewise.
	* generated/matmul_r16.c: Likewise.
	* generated/matmul_r4.c: Likewise.
	* generated/matmul_r8.c: Likewise.

	* common/config/aarch64/aarch64-common.c (aarch64_handle_option):
	Handle OPT_moutline_atomics.
	* config/aarch64/aarch64.c: Add outline-atomics to
	aarch64_attributes.

	* doc/extend.texi: Document the newly added target attribute.

	* gcc.target/aarch64/target_attr_20.c: New test.
	* gcc.target/aarch64/target_attr_21.c: New test.

	* gcc-changelog/git_update_version.py: Prepare the script, the
	only missing piece is pushing of the updated branches.

	* gcc-changelog/git_commit.py: Support DR entries/
	* gcc-changelog/test_email.py: New test for it.
	* gcc-changelog/test_patches.txt: New patch for it.

	* mklog.py: Support DR parsing.
	* test_mklog.py: New test for DR parsing.

Checking whether a filesystem::path constructor argument is an iterator
requires instantiating std::iterator_traits. In C++20 that checks for
satisfaction of std::iterator_traits constraints, which checks if the
type is copyable, which can end up recursing back to the path
constructor. The fix in LWG 3420 is to reorder the cpp17-iterator
concept's constraints to check if the type looks vaguely like an
iterator before checking copyable. That avoids the recursion for types
which definitely aren't iterators, but isn't foolproof.

	PR libstdc++/93983
	* include/bits/iterator_concepts.h (__detail::__cpp17_iterator):
	Reorder constraints to avoid recursion when constructors use
	iterator_traits (LWG 3420).
	* testsuite/24_iterators/customization_points/lwg3420.cc: New test.

	* include/experimental/socket (basic_socket::is_open()
	(basic_socket_acceptor::is_open()): Use _GLIBCXX_NODISCARD macro.

Define concepts and traits for checking type requirements.

	* include/experimental/bits/net.h (__endpoint, __protocol)
	(__acceptable_protocol, __inet_protocol): New concepts.
	(__detail::__is_endpoint): Move trait from <experimental/socket>.
	(__is_protocol, __is_acceptable_protocol, __is_inet_protocol): New
	traits.
	(__endpoint, __protocol, __acceptable_protocol): New variable
	templates.
	* include/experimental/socket (__is_endpoint): Move to net.h header.
	(basic_socket, basic_socket_acceptor): Check requirements.

Also add some missing member functions, nodiscard attributes, and
noexcept-specifiers.

	* include/experimental/executor (use_future_t::use_future_t()): Fix
	incorrect noexcept-specifier.
	* include/experimental/internet (basic_resolver_results): Adjust
	whitespace.
	* include/experimental/socket (__basic_socket_impl::release): Add
	member function.
	(basic_socket(io_context&, const endpoint_type&)): Fix argument to
	target constructor.
	(basic_socket::release(), basic_socket::release(error_code&)): Add
	missing member functions.
	(basic_socket::is_open()): Add nodiscard attribute.
	(basic_socket::close(error_code&)): Pass argument to base function.
	(basic_socket_acceptor::release())
	(basic_socket_acceptor::release(error_code&)): Add missing member
	functions.
	(basic_socket_acceptor::is_open()): Add nodiscard attribute.
	(basic_socket_streambuf::error()): Add noexcept.
	(basic_socket_iostream::error()): Likewise.
	* testsuite/experimental/net/socket/basic_socket.cc: New test.

	* include/experimental/buffer: Replace typedefs with
	alias-declarations.
	* include/experimental/executor: Likewise.
	* include/experimental/internet: Likewise.
	* include/experimental/socket: Likewise.
	* include/experimental/timer: Likewise.

2020-05-21  Uroš Bizjak  <ubizjak@gmail.com>

gcc/ChangeLog:
	PR target/95218

	* config/i386/mmx.md (*mmx_<code>v2sf): Do not mark
	operands 1 and 2 commutative.  Manually swap operands.
	(*mmx_nabsv2sf2): Ditto.

	Partially revert:

	* config/i386/i386.md (*<code>tf2_1):
	Mark operands 1 and 2 commutative.
	(*nabstf2_1): Ditto.
	* config/i386/sse.md (*<code><mode>2): Mark operands 1 and 2
	commutative.  Do not swap operands.
	(*nabs<mode>2): Ditto.

	* g++.dg/warn/Wconversion-null-2.C: Add explicit declarations for l()
	and g() with int, long, long long and __int20 arguments.
	* g++.dg/warn/Wconversion-null.C: Likewise.

This fixes regressions for aarch64 with -mabi=ilp32 of the
Wconversion-null*.C tests, introduced by 92ea8e1b.

The "g (int)" declaration is required for that target where
sizeof(int) == sizeof(long) == sizeof(void *).

To handle the msp430/-mlarge case, an explicit declaration of
"g (__int20)" is required.

gcc/testsuite/ChangeLog:

	* g++.dg/warn/Wconversion-null-2.C: Add explicit declarations for l()
	and g() with int, long, long long and __int20 arguments.
	* g++.dg/warn/Wconversion-null.C: Likewise.

This patch implements DR 2237 which says that a simple-template-id is
no longer valid as the declarator-id of a constructor or destructor;
see [diff.cpp17.class]#2.  It is not explicitly stated but out-of-line
destructors with a simple-template-id are also meant to be ill-formed
now.  (Out-of-line constructors like that are invalid since DR1435 I
think.)  This change only applies to C++20; it is not a DR against C++17.

I'm not crazy about the diagnostic in constructors but ISTM that
cp_parser_constructor_declarator_p shouldn't print errors.

	DR 2237
	* parser.c (cp_parser_unqualified_id): Reject simple-template-id as
	the declarator-id of a destructor.
	(cp_parser_constructor_declarator_p): Reject simple-template-id as
	the declarator-id of a constructor.

	* g++.dg/DRs/dr2237.C: New test.
	* g++.dg/parse/constructor2.C: Add dg-error for C++20.
	* g++.dg/parse/dtor12.C: Likewise.
	* g++.dg/parse/dtor4.C: Likewise.
	* g++.dg/template/dtor4.C: Adjust dg-error.
	* g++.dg/template/error34.C: Likewise.
	* g++.old-deja/g++.other/inline15.C: Only run for C++17 and lesses.
	* g++.old-deja/g++.pt/ctor2.C: Add dg-error for C++20.

This part of the cleanup patch turns out to require more pieces to
function correctly.  I must have got confused over which tree I was
testing.  The very first map has a different pointer to the file name,
so doesn't match with a pointer compare. We were relying on that.

	* c-common.c (try_to_locate_new_include_insertion_point): Revert change.

	* c-common.c (try_to_locate_new_include_insertion_point): Use
	strcmp to compare filenames.
	* c-lex.c (init_c_lex): Move declaration to initialization.
	* c-opts.c (handle_deferred_opts): Move cpp_get_deps call into
	deferred count loop.

DR 2289 clarified that since structured bindings have no C compatibility
implications, they should be unique in their declarative region, see
[basic.scope.declarative]/4.2.

The duplicate_decls hunk is the gist of the patch, but that alone would
not be enough to detect the 'A' case: cp_parser_decomposition_declaration
uses

13968       tree decl2 = start_decl (declarator, &decl_specs, SD_INITIALIZED,
13969                                NULL_TREE, NULL_TREE, &elt_pushed_scope);

to create the 'A' VAR_DECL but in this start_decl's grokdeclarator we
don't do fit_decomposition_lang_decl because the declarator kind is not
cdk_decomp, so then when start_decl calls maybe_push_decl, the decl 'A'
isn't DECL_DECOMPOSITION_P and we don't detect this case.  So I needed a
way to signal to start_decl that it should fit_decomposition_lang_decl.
In this patch, I'm adding SD_DECOMPOSITION flag to say that the variable
is initialized and it should also be marked as DECL_DECOMPOSITION_P.

	DR 2289
	PR c++/94553
	* cp-tree.h (SD_DECOMPOSITION): New flag.
	* decl.c (duplicate_decls): Make sure a structured binding is unique
	in its declarative region.
	(start_decl): If INITIALIZED is SD_DECOMPOSITION, call
	fit_decomposition_lang_decl.
	(grokdeclarator): Compare INITIALIZED directly to SD_* flags.
	* parser.c (cp_parser_decomposition_declaration): Pass SD_DECOMPOSITION
	to start_decl.

	* g++.dg/cpp1z/decomp52.C: New test.

2020-05-20  Uroš Bizjak  <ubizjak@gmail.com>

gcc/ChangeLog:
	PR target/95229
	* config/i386/sse.md (<code>v8qiv8hi2): Use
	simplify_gen_subreg instead of simplify_subreg.
	(<code>v8qiv8si2): Ditto.
	(<code>v4qiv4si2): Ditto.
	(<code>v4hiv4si2): Ditto.
	(<code>v8qiv8di2): Ditto.
	(<code>v4qiv4di2): Ditto.
	(<code>v2qiv2di2): Ditto.
	(<code>v4hiv4di2): Ditto.
	(<code>v2hiv2di2): Ditto.
	(<code>v2siv2di2): Ditto.

gcc/testsuite/ChangeLog:
	PR target/95229
	* g++.target/i386/pr95229.C: New test.

2020-05-20  Uroš Bizjak  <ubizjak@gmail.com>

gcc/ChangeLog:
	PR target/95238
	* config/i386/i386.md (*pushsi2_rex64):
	Use "e" constraint instead of "i".

	* gcc-changelog/git_commit.py: Add author_tuple
	only if not present in author_lines.
	* gcc-changelog/test_email.py: New test.
	* gcc-changelog/test_patches.txt: Add new patch.