A non-standard clock may tick more slowly than
std::chrono::steady_clock.  This means that we risk returning false
early when the specified timeout may not have expired. This can be
avoided by looping until the timeout time as reported by the
non-standard clock has been reached.

Unfortunately, we have no way to tell whether the non-standard clock
ticks more quickly that std::chrono::steady_clock. If it does then we
risk returning later than would be expected, but that is unavoidable and
permitted by the standard.

2019-12-02  Mike Crowe  <mac@mcrowe.com>

	PR libstdc++/91906 Fix timed_mutex::try_lock_until on arbitrary clock
	* include/std/mutex (__timed_mutex_impl::_M_try_lock_until): Loop
	until the absolute timeout time is reached as measured against the
	appropriate clock.
	* testsuite/util/slow_clock.h: New file. Move implementation of
	slow_clock test class.
	* testsuite/30_threads/condition_variable/members/2.cc: Include
	slow_clock from header.
	* testsuite/30_threads/shared_timed_mutex/try_lock/3.cc: Convert
	existing test to templated function so that it can be called with
	both system_clock and steady_clock.
	* testsuite/30_threads/timed_mutex/try_lock_until/3.cc: Also run test
	using slow_clock to test above fix.
	* testsuite/30_threads/recursive_timed_mutex/try_lock_until/3.cc:
	Likewise.
	* testsuite/30_threads/recursive_timed_mutex/try_lock_until/4.cc: Add
	new test that try_lock_until behaves as try_lock if the timeout has
	already expired or exactly matches the current time.

From-SVN: r278902

The pthread_mutex_clocklock function is available in glibc since the
2.30 release. If this function is available in the C library it can be
used to fix PR libstdc++/78237 by supporting steady_clock properly with
timed_mutex.

This means that code using timed_mutex::try_lock_for or
timed_mutex::wait_until with steady_clock is no longer subject to timing
out early or potentially waiting for much longer if the system clock is
warped at an inopportune moment.

If pthread_mutex_clocklock is available then steady_clock is deemed to
be the "best" clock available which means that it is used for the
relative try_lock_for calls and absolute try_lock_until calls using
steady_clock and user-defined clocks. Calls explicitly using
system_clock (aka high_resolution_clock) continue to use CLOCK_REALTIME
via __gthread_cond_timedwait.

If pthread_mutex_clocklock is not available then system_clock is deemed
to be the "best" clock available which means that the previous
suboptimal behaviour remains.

2019-12-02  Mike Crowe  <mac@mcrowe.com>

	PR libstdc++/78237 Add full steady_clock support to timed_mutex
	* acinclude.m4 (GLIBCXX_CHECK_PTHREAD_MUTEX_CLOCKLOCK): Define to
	detect presence of pthread_mutex_clocklock function.
	* config.h.in: Regenerate.
	* configure: Regenerate.
	* configure.ac: Call GLIBCXX_CHECK_PTHREAD_MUTEX_CLOCKLOCK.
	* include/std/mutex (__timed_mutex_impl): Remove unnecessary __clock_t.
	(__timed_mutex_impl::_M_try_lock_for): Use best clock to turn relative
	timeout into absolute timeout.
	(__timed_mutex_impl::_M_try_lock_until): Keep existing implementation
	for system_clock. Add new implementation for steady_clock that calls
	_M_clocklock. Modify overload for user-defined clock to use a relative
	wait so that it automatically uses the best clock.
	[_GLIBCXX_USE_PTHREAD_MUTEX_CLOCKLOCK] (timed_mutex::_M_clocklock):
	New member function.
	(recursive_timed_mutex::_M_clocklock): Likewise.

From-SVN: r278901

2019-12-02  Mike Crowe  <mac@mcrowe.com>

	* testsuite/30_threads/recursive_timed_mutex/try_lock_until/3.cc:
	New test. Ensure that timed_mutex::try_lock_until actually times out
	after the specified time when using both system_clock and
	steady_clock.
	* testsuite/30_threads/timed_mutex/try_lock_until/3.cc: New test.
	Likewise but for recursive_timed_mutex.
	* testsuite/30_threads/timed_mutex/try_lock_until/57641.cc: Template
	test functions and use them to test both steady_clock and system_clock.
	* testsuite/30_threads/unique_lock/locking/4.cc: Likewise. Wrap call
	to timed_mutex::try_lock_until in VERIFY macro to check its return
	value.

From-SVN: r278900

2019-12-02  Martin Liska  <mliska@suse.cz>

	* ipa-devirt.c (warn_types_mismatch): Use get_odr_name_for_type
	function.
	(debug_tree_odr_name): New.
	* ipa-utils.h (get_odr_name_for_type): New.
2019-12-02  Martin Liska  <mliska@suse.cz>

	* g++.dg/lto/odr-7_0.C: New test.
	* g++.dg/lto/odr-7_1.C: New test.

From-SVN: r278898

	* g++.dg/lto/inline-crossmodule-1_0.C: fix template.

From-SVN: r278897

2019-12-02  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/92742
	* tree-vect-loop.c (vect_fixup_reduc_chain): Do not
	touch the def-type but verify it is consistent with the
	original stmts.

	* gcc.dg/torture/pr92742.c: New testcase.

From-SVN: r278896

	PR tree-optimization/92712
	* match.pd ((A * B) +- A -> (B +- 1) * A,
	A +- (A * B) -> (1 +- B) * A): Allow optimizing signed integers
	even when we don't know anything about range of A, but do know
	something about range of B and the simplification won't introduce
	new UB.

	* gcc.dg/tree-ssa/pr92712-1.c: New test.
	* gcc.dg/tree-ssa/pr92712-2.c: New test.
	* gcc.dg/tree-ssa/pr92712-3.c: New test.
	* gfortran.dg/loop_versioning_1.f90: Adjust expected number of
	likely to be innermost dimension messages.
	* gfortran.dg/loop_versioning_10.f90: Likewise.
	* gfortran.dg/loop_versioning_6.f90: Likewise.

From-SVN: r278894

2019-12-02  Feng Xue <fxue@os.amperecomputing.com>

        PR ipa/92133
        * doc/invoke.texi (ipa-cp-max-recursive-depth): Document new option.
        (ipa-cp-min-recursive-probability): Likewise.
        * params.opt (ipa-cp-max-recursive-depth): New.
        (ipa-cp-min-recursive-probability): Likewise.
        * ipa-cp.c (ipcp_lattice<valtype>::add_value): Add two new parameters
        val_p and unlimited.
        (self_recursively_generated_p): New function.
        (get_val_across_arith_op): Likewise.
        (propagate_vals_across_arith_jfunc): Add constant propagation for
        self-recursive function.
        (incorporate_penalties): Do not penalize pure self-recursive function.
        (good_cloning_opportunity_p): Dump node_is_self_scc flag.
        (propagate_constants_topo): Set node_is_self_scc flag for cgraph node.
        (get_info_about_necessary_edges): Relax hotness check for edge to
        self-recursive function.
        * ipa-prop.h (ipa_node_params): Add new field node_is_self_scc.

2019-12-02  Feng Xue  <fxue@os.amperecomputing.com>

        PR ipa/92133
        * gcc.dg/ipa/ipa-clone-2.c: New test.

From-SVN: r278893

2019-12-01  Sandra Loosemore  <sandra@codesourcery.com>

	Fix bugs relating to flexibly-sized objects in nios2 backend.

	PR target/92499

	gcc/c/
	* c-decl.c (flexible_array_type_p): Move to common code.

	gcc/
	* config/nios2/nios2.c (nios2_in_small_data_p): Do not consider
	objects of flexible types to be small if they have internal linkage
	or are declared extern.
	* config/nios2/nios2.h (ASM_OUTPUT_ALIGNED_LOCAL): Replace with...
	(ASM_OUTPUT_ALIGNED_DECL_LOCAL): ...this.  Use targetm.in_small_data_p
	instead of the size of the object initializer.
	* tree.c (flexible_array_type_p): Move from C front end, and
	generalize to handle fields in non-C structures.
	* tree.h (flexible_array_type_p): Declare.

	gcc/testsuite/
	* gcc.target/nios2/pr92499-1.c: New.
	* gcc.target/nios2/pr92499-2.c: New.
	* gcc.target/nios2/pr92499-3.c: New.

From-SVN: r278891

P9LE generated instruction is not worse than P8LE.
mtvsrdd;xxlnot;stxv vs. not;not;std;std.
It can have longer latency, but latency via memory is not so critical,
and this does save decode and other resources.  It's hard to choose
which is best.  Update the test case to fix failures.

gcc/testsuite/ChangeLog:

	2019-12-02  Luo Xiong Hu  <luoxhu@linux.ibm.com>

	PR testsuite/92398
	* gcc.target/powerpc/pr72804.c: Split the store function to...
	* gcc.target/powerpc/pr92398.h: ... this one.  New.
	* gcc.target/powerpc/pr92398.p9+.c: New.
	* gcc.target/powerpc/pr92398.p9-.c: New.
	* lib/target-supports.exp (check_effective_target_p8): New.
	(check_effective_target_p9+): New.

From-SVN: r278890

From-SVN: r278889

re PR libfortran/90374 (Fortran 2018: Support d0.d, e0.d, es0.d, en0.d, g0.d and ew.d e0 edit descriptors for output)

2019-12-01  Jerry DeLisle  <jvdelisle@gcc.ngu.org>

	PR fortran/90374
	* io/format.c (parse_format_list): Add braces to disambiguate
	conditional.

From-SVN: r278886

	* profile-count.h (profile_count::operator<): Use IPA value for
	comparsion.
	(profile_count::operator>): Likewise.
	(profile_count::operator<=): Likewise.
	(profile_count::operator>=): Likewise.
	* predict.c (maybe_hot_count_p): Do not convert to gcov_type.

From-SVN: r278885

From-SVN: r278883

	* ipa-inline.c (compute_max_insns): Return int64_t.
	(inline_small_functions): Simplify.

From-SVN: r278880

	* tree-cfg.c (execute_fixup_cfg): Update also max_bb_count when
	scaling happen.

From-SVN: r278879

2019-11-30  Jan Hubicka  <hubicka@ucw.cz>

	* cgraph.h (symtab_node): Add symver flag.
	* cgraphunit.c (process_symver_attribute): New.
	(process_common_attributes): Use process_symver_attribute.
	* lto-cgraph.c (lto_output_node): Stream symver.
	(lto_output_varpool_node): Stream symver.
	(input_overwrite_node): Stream symver.
	(input_varpool_node): Stream symver.
	* output.h (do_assemble_symver): Decalre.
	* symtab.c (symtab_node::dump_base): Dump symver.
	(symtab_node::verify_base): Verify symver.
	(symtab_node::resolve_alias): Handle symver.
	* varasm.c (do_assemble_symver): New function.
	* varpool.c (varpool_node::assemble_aliases): Use it.
	* doc/extend.texi: (symver attribute): Document.
	* config/elfos.h (ASM_OUTPUT_SYMVER_DIRECTIVE): New.

c-family/ChangeLog:

2019-11-30  Jan Hubicka  <hubicka@ucw.cz>

	* c-attribs.c (handle_symver_attribute): New function
	(c_common_attributes): Add symver.

From-SVN: r278878

This patch adds a new target hook to check whether there are any
target-specific reasons why a type cannot be used in a certain
source-language context.  It works in a similar way to existing
hooks like TARGET_INVALID_CONVERSION and TARGET_INVALID_UNARY_OP.

The reason for adding the hook is to report invalid uses of SVE types.
Throughout a TU, the SVE vector and predicate types represent values
that can be stored in an SVE vector or predicate register.  At certain
points in the TU we might be able to generate code that assumes the
registers have a particular size, but often we can't.  In some cases
we might even make multiple different assumptions in the same TU
(e.g. when implementing an ifunc for multiple vector lengths).

But SVE types themselves are the same type throughout.  The register
size assumptions change how we generate code, but they don't change
the definition of the types.

This means that the types do not have a fixed size at the C level
even when -msve-vector-bits=N is in effect.  It also means that the
size does not work in the same way as for C VLAs, where the abstract
machine evaluates the size at a particular point and then carries that
size forward to later code.

The SVE ACLE deals with this by making it invalid to use C and C++
constructs that depend on the size or layout of SVE types.  The spec
refers to the types as "sizeless" types and defines their semantics as
edits to the standards.  See:

  https://gcc.gnu.org/ml/gcc-patches/2018-10/msg00868.html

for a fuller description and:

  https://gcc.gnu.org/ml/gcc/2019-11/msg00088.html

for a recent update on the status.

However, since all current sizeless types are target-specific built-in
types, there's no real reason for the frontends to handle them directly.
They can just hand off the checks to target code instead.  It's then
possible for the errors to refer to "SVE types" rather than "sizeless
types", which is likely to be more meaningful to users.

There is a slight overlap between the new tests and the ones for
gnu_vector_type_p in r277950, but here the emphasis is on testing
sizelessness.

2019-11-30  Richard Sandiford  <richard.sandiford@arm.com>

gcc/
	* target.h (type_context_kind): New enum.
	(verify_type_context): Declare.
	* target.def (verify_type_context): New target hook.
	* doc/tm.texi.in (TARGET_VERIFY_TYPE_CONTEXT): Likewise.
	* doc/tm.texi: Regenerate.
	* tree.c (verify_type_context): New function.
	* config/aarch64/aarch64-protos.h (aarch64_sve::verify_type_context):
	Declare.
	* config/aarch64/aarch64-sve-builtins.cc (verify_type_context):
	New function.
	* config/aarch64/aarch64.c (aarch64_verify_type_context): Likewise.
	(TARGET_VERIFY_TYPE_CONTEXT): Define.

gcc/c-family/
	* c-common.c (pointer_int_sum): Use verify_type_context to check
	whether the target allows pointer arithmetic for the types involved.
	(c_sizeof_or_alignof_type, c_alignof_expr): Use verify_type_context
	to check whether the target allows sizeof and alignof operations
	for the types involved.

gcc/c/
	* c-decl.c (start_decl): Allow initialization of variables whose
	size is a POLY_INT_CST.
	(finish_decl): Use verify_type_context to check whether the target
	allows variables with a particular type to have static or thread-local
	storage duration.  Don't raise a second error if such variables do
	not have a constant size.
	(grokdeclarator): Use verify_type_context to check whether the
	target allows fields or array elements to have a particular type.
	* c-typeck.c (pointer_diff): Use verify_type_context to test whether
	the target allows pointer difference for the types involved.
	(build_unary_op): Likewise for pointer increment and decrement.

gcc/testsuite/
	* gcc.target/aarch64/sve/acle/general-c/sizeless-1.c: New test.
	* gcc.target/aarch64/sve/acle/general-c/sizeless-2.c: Likewise.

From-SVN: r278877

	* cgraph.c (cgraph_node::dump): Dump unit_id and merged_extern_inline.
	* cgraph.h (cgraph_node): Add unit_id and
	merged_extern_inline.
	(symbol_table): Add max_unit.
	(symbol_table::symbol_table): Initialize it.
	* cgraphclones.c (duplicate_thunk_for_node): Copy unit_id.
	merged_comdat, merged_extern_inline.
	(cgraph_node::create_clone): Likewise.
	(cgraph_node::create_version_clone): Likewise.
	* ipa-fnsummary.c (dump_ipa_call_summary): Dump info about cross module
	calls.
	* ipa-fnsummary.h (cross_module_call_p): New inline function.
	* ipa-inline-analyssi.c (simple_edge_hints): Use it.
	* ipa-inline.c (inline_small_functions): Likewise.
	* lto-symtab.c (lto_cgraph_replace_node): Record merged_extern_inline;
	copy merged_comdat and merged_extern_inline.
	* lto-cgraph.c (lto_output_node): Stream out merged_comdat,
	merged_extern_inline and unit_id.
	(input_overwrite_node): Stream in these.
	(input_cgraph_1): Set unit_base.
	* lto-streamer.h (lto_file_decl_data): Add unit_base.
	* symtab.c (symtab_node::make_decl_local): Record former_comdat.

	* g++.dg/lto/inline-crossmodule-1.h: New testcase.
	* g++.dg/lto/inline-crossmodule-1_0.C: New testcase.
	* g++.dg/lto/inline-crossmodule-1_1.C: New testcase.

From-SVN: r278876

2019-11-30  Thomas Koenig  <tkoenig@gcc.gnu.org>

	PR fortran/91783
	* dependency.c (gfc_dep_resolver): Do not look at _data
	component if present.

2019-11-30  Thomas Koenig  <tkoenig@gcc.gnu.org>

	PR fortran/91783
	* gfortran.dg/dependency_56.f90: New test.

From-SVN: r278873

Fix an issue with the GCC driver and the `-x' option where a warning is
issued in an invocation like:

$ riscv64-linux-gnu-gcc -print-multi-directory -x c++
riscv64-linux-gnu-gcc: warning: '-x c++' after last input file has no effect
lib64/lp64d
$ 

where no inputs were given and hence the use of `-x' is irrelevant.
The statement printed is also untrue as the `-x' does not come after the
last input file given that none was given.  Do not print it then if no
inputs were supplied.

	* gcc.c (process_command): Only warn about an ineffective `-x'
	option if any input files have actually been supplied.

From-SVN: r278872

The `--enable-version-specific-runtime-libs' configuration option is now
supported throughout all of our target library subdirectories, so update
installation documentation accordingly and also mention that the default
for the option is `yes' for libada and `no' for the remaining libraries.

	gcc/
	* doc/install.texi (Options specification): Remove the list of
	target library subdirectories supporting
	`--enable-version-specific-runtime-libs'.  Document defaults for
	the option.

From-SVN: r278871

	* acinclude.m4 (GLIBCXX_ENABLE_FILESYSTEM_TS): Enable by default for
	mingw targets.
	* configure: Regenerate.

From-SVN: r278870

This function failed to compile when called with a std::string.

Also, constructing a path with a char8_t string did not correctly treat
the string as already UTF-8 encoded.

	* include/bits/fs_path.h (u8path(InputIterator, InputIterator))
	(u8path(const Source&)) [_GLIBCXX_FILESYSTEM_IS_WINDOWS]: Simplify
	conditions.
	* include/experimental/bits/fs_path.h [_GLIBCXX_FILESYSTEM_IS_WINDOWS]
	(__u8path(const Source&, char)): Add overloads for std::string and
	types convertible to std::string.
	(_Cvt::_S_wconvert): Add a new overload for char8_t strings and use
	codecvt_utf8_utf16 to do the correct conversion.

From-SVN: r278869

From-SVN: r278868

2019-11-29  Vladimir Makarov  <vmakarov@redhat.com>

	PR rtl-optimization/92283
	* lra.c (lra): Update reg notes after inheritance sub-pass and
	before constraint sub-pass.

From-SVN: r278865

2019-11-29  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/91003
	* tree-vect-slp.c (vect_mask_constant_operand_p): Pass in the
	operand number, avoid handling the non-condition operands of
	COND_EXPRs as comparisons.
	(vect_get_constant_vectors): Pass down the operand number.
	(vect_get_slp_defs): Likewise.

	* gfortran.dg/pr91003.f90: New testcase.

From-SVN: r278860

	* include/bits/fs_path.h (path::operator/=): Change template-head to
	use typename instead of class.
	* include/experimental/bits/fs_path.h (path::operator/=): Likewise.
	* include/std/ostream (operator<<): Likewise.

From-SVN: r278859

New tests

This patch adds new tests to validate new deleted overloads of wchar_t,
char8_t, char16_t, and char32_t for ordinary and wide formatted character and
string ostream inserters.

Additionally, new tests are added to validate invocations of u8path with
sequences of char8_t for both the C++17 and filesystem TS implementations.

2019-11-29  Tom Honermann  <tom@honermann.net>

	New tests
	* testsuite/27_io/basic_ostream/inserters_character/char/deleted.cc:
	New test to validate deleted overloads of character and string
	inserters for narrow ostreams.
	* testsuite/27_io/basic_ostream/inserters_character/wchar_t/deleted.cc:
	New test to validate deleted overloads of character and string
	inserters for wide ostreams.
	* testsuite/27_io/filesystem/path/factory/u8path-char8_t.cc: New test
	to validate u8path invocations with sequences of char8_t.
	* testsuite/experimental/filesystem/path/factory/u8path-char8_t.cc:
	New test to validate u8path invocations with sequences of char8_t.

From-SVN: r278858

Updates to existing tests

This patch updates existing tests to validate the new value for the
__cpp_lib_char8_t feature test macros and to exercise u8path factory
function invocations with std::string, std::string_view, and interator
pair arguments.

2019-11-29  Tom Honermann  <tom@honermann.net>

	Updates to existing tests
	* testsuite/experimental/feat-char8_t.cc: Updated the expected
	__cpp_lib_char8_t feature test macro value.
	* testsuite/27_io/filesystem/path/factory/u8path.cc: Added testing of
	u8path invocation with std::string, std::string_view, and iterators
	thereof.
	* testsuite/experimental/filesystem/path/factory/u8path.cc: Added
	testing of u8path invocation with std::string, std::string_view, and
	iterators thereof.

From-SVN: r278857

Update feature test macro, add deleted operators, update u8path

This patch increments the __cpp_lib_char8_t feature test macro, adds deleted
operator<< overloads for basic_ostream, and modifies u8path to accept
sequences of char8_t for both the C++17 implementation of std::filesystem, and
the filesystem TS implementation.

The implementation mechanism used for u8path differs between the C++17 and
filesystem TS implementations.  The changes to the former take advantage of
C++17 'if constexpr'.  The changes to the latter retain C++11 compatibility
and rely on tag dispatching.

2019-11-29  Tom Honermann  <tom@honermann.net>

	Update feature test macro, add deleted operators, update u8path
	* include/bits/c++config: Bumped the value of the __cpp_lib_char8_t
	feature test macro.
	* include/bits/fs_path.h (u8path): Modified u8path to accept sequences
	of char8_t.
	* include/experimental/bits/fs_path.h (u8path): Modified u8path to
	accept sequences of char8_t.
	* include/std/ostream: Added deleted overloads of wchar_t, char8_t,
	char16_t, and char32_t for ordinary and wide formatted character and
	string inserters.

From-SVN: r278856

Decouple constraints for u8path from path constructors

This patch moves helper classes and functions for std::filesystem::path out of
the class definition to a detail namespace so that they are available to the
implementations of std::filesystem::u8path.  Prior to this patch, the SFINAE
constraints for those implementations were specified via delegation to the
overloads of path constructors with a std::locale parameter; it just so
happened that those overloads had the same constraints.  As of P1423R3, u8path
and those overloads no longer have the same constraints, so this dependency
must be broken.

This patch also updates the experimental implementation of the filesystem TS
to add SFINAE constraints to its implementations of u8path.  These functions
were previously unconstrained and marked with a TODO comment.

This patch does not provide any intentional behavioral changes other than the
added constraints to the experimental filesystem TS implementation of u8path.

Alternatives to this refactoring would have been to make the u8path overloads
friends of class path, or to make the helpers public members. Both of those
approaches struck me as less desirable than this approach, though this
approach does require more code changes and will affect implementation detail
portions of mangled names for path constructors and inline member functions
(mostly function template specializations).

2019-11-29  Tom Honermann  <tom@honermann.net>

	Decouple constraints for u8path from path constructors
	* include/bits/fs_path.h: Moved helper utilities out of
	std::filesystem::path into a detail namespace to make them
	available for use by u8path.
	* include/experimental/bits/fs_path.h: Moved helper utilities out
	of std::experimental::filesystem::v1::path into a detail
	namespace to make them available for use by u8path.

From-SVN: r278855

The function maybe_resimplify_conditional_op uses operation_could_trap_p to
check if the resulting operation of a simplification can trap.  Because of the
changes introduced by revision r276659, this results in an ICE due to a
violated assertion in operation_could_trap_p if the operation is a COND_EXPR or
a VEC_COND_EXPR.  The changes have allowed those expressions to trap and
whether they do cannot be determined without considering their condition
which is not available to operation_could_trap_p.

Change maybe_resimplify_conditional_op to inspect the condition of
COND_EXPRs and VEC_COND_EXPRs to determine if they can trap.

From-SVN: r278853

When dissolving an SLP-only group of accesses, we should only set
the gap to group_size - 1 for normal non-strided groups.

2019-11-29  Richard Sandiford  <richard.sandiford@arm.com>

gcc/
	PR tree-optimization/92677
	* tree-vect-loop.c (vect_dissolve_slp_only_groups): Set the gap
	to zero when dissolving a group of strided accesses.

gcc/testsuite/
	PR tree-optimization/92677
	* gcc.dg/vect/pr92677.c: New test.

From-SVN: r278852

Now that stmt_vec_info records the choice between vector mask
types and normal nonmask types, we can use that information in
vect_get_vector_types_for_stmt instead of deferring the choice
of vector type till later.

vect_get_mask_type_for_stmt used to check whether the boolean inputs
to an operation:
(a) consistently used mask types or consistently used nonmask types; and
(b) agreed on the number of elements.

(b) shouldn't be a problem when (a) is met.  If the operation
consistently uses mask types, tree-vect-patterns.c will have corrected
any mismatches in mask precision.  (This is because we only use mask
types for a small well-known set of operations and tree-vect-patterns.c
knows how to handle any that could have different mask precisions.)
And if the operation consistently uses normal nonmask types, there's
no reason why booleans should need extra vector compatibility checks
compared to ordinary integers.

So the potential difficulties all seem to come from (a).  Now that
we've chosen the result type ahead of time, we also have to consider
whether the outputs and inputs consistently use mask types.

Taking each vectorizable_* routine in turn:

- vectorizable_call

    vect_get_vector_types_for_stmt only handled booleans specially
    for gassigns, so vect_get_mask_type_for_stmt never had chance to
    handle calls.  I'm not sure we support any calls that operate on
    booleans, but as things stand, a boolean result would always have
    a nonmask type.  Presumably any vector argument would also need to
    use nonmask types, unless it corresponds to internal_fn_mask_index
    (which is already a special case).

    For safety, I've added a check for mask/nonmask combinations here
    even though we didn't check this previously.

- vectorizable_simd_clone_call

    Again, vect_get_mask_type_for_stmt never had chance to handle calls.
    The result of the call will always be a nonmask type and the patch
    for PR 92710 rejects mask arguments.  So all booleans should
    consistently use nonmask types here.

- vectorizable_conversion

    The function already rejects any conversion between booleans in which
    one type isn't a mask type.

- vectorizable_operation

    This function definitely needs a consistency check, e.g. to handle
    & and | in which one operand is loaded from memory and the other is
    a comparison result.  Ideally we'd handle this via pattern stmts
    instead (like we do for the all-mask case), but that's future work.

- vectorizable_assignment

    VECT_SCALAR_BOOLEAN_TYPE_P requires single-bit precision, so the
    current code already rejects problematic cases.

- vectorizable_load

    Loads always produce nonmask types and there are no relevant inputs
    to check against.

- vectorizable_store

    vect_check_store_rhs already rejects mask/nonmask combinations
    via useless_type_conversion_p.

- vectorizable_reduction
- vectorizable_lc_phi

    PHIs always have nonmask types.  After the change above, attempts
    to combine the PHI result with a mask type would be rejected by
    vectorizable_operation.  (Again, it would be better to handle
    this using pattern stmts.)

- vectorizable_induction

    We don't generate inductions for booleans.

- vectorizable_shift

    The function already rejects boolean shifts via type_has_mode_precision_p.

- vectorizable_condition

    The function already rejects mismatches via useless_type_conversion_p.

- vectorizable_comparison

    The function already rejects comparisons between mask and nonmask types.
    The result is always a mask type.

2019-11-29  Richard Sandiford  <richard.sandiford@arm.com>

gcc/
	PR tree-optimization/92596
	* tree-vect-stmts.c (vectorizable_call): Punt on hybrid mask/nonmask
	operations.
	(vectorizable_operation): Likewise, instead of relying on
	vect_get_mask_type_for_stmt to do this.
	(vect_get_vector_types_for_stmt): Always return a vector type
	immediately, rather than deferring the choice for boolean results.
	Use a vector mask type instead of a normal vector if
	vect_use_mask_type_p.
	(vect_get_mask_type_for_stmt): Delete.
	* tree-vect-loop.c (vect_determine_vf_for_stmt_1): Remove
	mask_producers argument and special boolean_type_node handling.
	(vect_determine_vf_for_stmt): Remove mask_producers argument and
	update calls to vect_determine_vf_for_stmt_1.  Remove doubled call.
	(vect_determine_vectorization_factor): Update call accordingly.
	* tree-vect-slp.c (vect_build_slp_tree_1): Remove special
	boolean_type_node handling.
	(vect_slp_analyze_node_operations_1): Likewise.

gcc/testsuite/
	PR tree-optimization/92596
	* gcc.dg/vect/bb-slp-pr92596.c: New test.
	* gcc.dg/vect/bb-slp-43.c: Likewise.

From-SVN: r278851

search_type_for_mask uses a worklist to search a chain of boolean
operations for a natural vector mask type.  This patch instead does
that in vect_determine_stmt_precisions, where we also look for
overpromoted integer operations.  We then only need to compute
the precision once and can cache it in the stmt_vec_info.

The new function vect_determine_mask_precision is supposed
to handle exactly the same cases as search_type_for_mask_1,
and in the same way.  There's a lot we could improve here,
but that's not stage 3 material.

I wondered about sharing mask_precision with other fields like
operation_precision, but in the end that seemed too dangerous.
We have patterns to convert between boolean and non-boolean
operations and it would be very easy to get mixed up about
which case the fields are describing.

2019-11-29  Richard Sandiford  <richard.sandiford@arm.com>

gcc/
	* tree-vectorizer.h (stmt_vec_info::mask_precision): New field.
	(vect_use_mask_type_p): New function.
	* tree-vect-patterns.c (vect_init_pattern_stmt): Copy the
	mask precision to the pattern statement.
	(append_pattern_def_seq): Add a scalar_type_for_mask parameter
	and use it to initialize the new stmt's mask precision.
	(search_type_for_mask_1): Delete.
	(search_type_for_mask): Replace with...
	(integer_type_for_mask): ...this new function.  Use the information
	cached in the stmt_vec_info.
	(vect_recog_bool_pattern): Update accordingly.
	(build_mask_conversion): Pass the scalar type associated with the
	mask type to append_pattern_def_seq.
	(vect_recog_mask_conversion_pattern): Likewise.  Call
	integer_type_for_mask instead of search_type_for_mask.
	(vect_convert_mask_for_vectype): Call integer_type_for_mask instead
	of search_type_for_mask.
	(possible_vector_mask_operation_p): New function.
	(vect_determine_mask_precision): Likewise.
	(vect_determine_stmt_precisions): Call it.

From-SVN: r278850

This patch makes vect_get_mask_type_for_stmt and
get_mask_type_for_scalar_type take a group size instead of
the SLP node, so that later patches can call it before an
SLP node has been built.

2019-11-29  Richard Sandiford  <richard.sandiford@arm.com>

gcc/
	* tree-vectorizer.h (get_mask_type_for_scalar_type): Replace
	the slp_tree parameter with a group size parameter.
	(vect_get_mask_type_for_stmt): Likewise.
	* tree-vect-stmts.c (get_mask_type_for_scalar_type): Likewise.
	(vect_get_mask_type_for_stmt): Likewise.
	* tree-vect-slp.c (vect_slp_analyze_node_operations_1): Update
	call accordingly.

From-SVN: r278849

vectorizable_operation returned false for codes that are handled by
vectorizable_shift, but only after it had already done a lot of work.
Checking earlier should be more efficient and avoid polluting the logs
with duplicate info.

Also, there was no such early-out for comparisons or COND_EXPRs.
Fixing that avoids a false scan-tree-dump hit with a later patch.

2019-11-29  Richard Sandiford  <richard.sandiford@arm.com>

gcc/
	* tree-vect-stmts.c (vectorizable_operation): Punt early
	on codes that are handled elsewhere.

From-SVN: r278848

vect_recog_bool_pattern assumed that a comparison between two booleans
should always become a comparison of vector mask types (implemented as an
XOR_EXPR).  But if the booleans in question are generated as data values
(e.g. because they're loaded directly from memory), we should treat them
like ordinary integers instead, just as we do for boolean logic ops whose
operands are loaded from memory.  vect_get_mask_type_for_stmt already
handled this case:

      /* We may compare boolean value loaded as vector of integers.
	 Fix mask_type in such case.  */
      if (mask_type
	  && !VECTOR_BOOLEAN_TYPE_P (mask_type)
	  && gimple_code (stmt) == GIMPLE_ASSIGN
	  && TREE_CODE_CLASS (gimple_assign_rhs_code (stmt)) == tcc_comparison)
	mask_type = truth_type_for (mask_type);

and not handling it here complicated later patches.

The initial list of targets for vect_bool_cmp is deliberately conservative.

2019-11-29  Richard Sandiford  <richard.sandiford@arm.com>

gcc/
	* doc/sourcebuild.texi (vect_bool_cmp): Document.
	* tree-vect-patterns.c (search_type_for_mask_1): If neither
	operand to a boolean comparison is a natural vector mask,
	handle both operands like normal integers instead.

gcc/testsuite/
	* gcc.dg/vect/vect-bool-cmp-2.c: New test.
	* lib/target-supports.exp (check_effective_target_vect_bool_cmp): New
	effective target procedure.

From-SVN: r278847

This fixes two related problems.

The iterators for node-based containers use nested typedefs such as
std::list<T>::iterator::_Node to denote their node types. As reported in
https://bugzilla.redhat.com/show_bug.cgi?id=1053438 those typedefs are
not always present in the debug info. That means the pretty printers
cannot find them using gdb.lookup_type (via the find_type helper).
Instead of looking up the nested typedefs this patch makes the printers
look up the actual class templates directly.

A related problem (and the original topic of PR 91997) is that GDB fails
to find types via gdb.lookup_type when printing a backtrace from a
non-C++ functiion: https://sourceware.org/bugzilla/show_bug.cgi?id=25234
That is also solved by not looking up the nested typedef.

	PR libstdc++/91997
	* python/libstdcxx/v6/printers.py (find_type): Fail more gracefully
	if we run out of base classes to look at.
	(llokup_templ_spec, lookup_node_type): New utilities to find node
	types for node-based containers.
	(StdListPrinter.children, NodeIteratorPrinter.__init__)
	(NodeIteratorPrinter.to_string, StdSlistPrinter.children)
	(StdSlistIteratorPrinter.to_string, StdRbtreeIteratorPrinter.__init__)
	(StdMapPrinter.children, StdSetPrinter.children)
	(StdForwardListPrinter.children): Use lookup_node_type instead of
	find_type.
	(StdListIteratorPrinter.__init__, StdFwdListIteratorPrinter.__init__):
	Pass name of node type to NodeIteratorPrinter constructor.
	(Tr1HashtableIterator.__init__): Rename argument.
	(StdHashtableIterator.__init__): Likewise. Use lookup_templ_spec
	instead of find_type.
	* testsuite/libstdc++-prettyprinters/59161.cc: Remove workaround for
	_Node typedef not being present in debuginfo.
	* testsuite/libstdc++-prettyprinters/91997.cc: New test.

From-SVN: r278846