This fixes a typo in combine_reg_notes in the load/store pair fusion
pass. As it stands, the calls to filter_notes store any
REG_FRAME_RELATED_EXPR to fr_expr with the following association:
- i2 -> fr_expr[0]
- i1 -> fr_expr[1]
but then the checks inside the following if statement expect the
opposite (more natural) association, i.e.:
- i2 -> fr_expr[1]
- i1 -> fr_expr[0]
this patch fixes the oversight by swapping the fr_expr indices in the
calls to filter_notes.
In hindsight it would probably have been less confusing / error-prone to
have combine_reg_notes take an array of two insns, then we wouldn't have
to mix 1-based and 0-based indexing as well as remembering to call
filter_notes in reverse program order. This however is a minimal fix
for backporting purposes.
gcc/ChangeLog:
PR target/114936
* config/aarch64/aarch64-ldp-fusion.cc (combine_reg_notes):
Ensure insn iN has its REG_FRAME_RELATED_EXPR (if any) stored in
FR_EXPR[N-1], thus matching the correspondence expected by the
copy_rtx calls.
This fixes a couple of tests (gcc.dg/vect/pr109011-*.c) on s390 where
loops are unrolled although -fno-unroll-loops is specified.
gcc/ChangeLog:
* tree-ssa-loop-prefetch.cc (determine_unroll_factor): Honour
-fno-unroll-loops.
When insert_updated_phi_nodes_for tries to skip pruning the IDF to
blocks dominated by the nearest common dominator of the set of
definition blocks it compares against ENTRY_BLOCK but that's never
going to be the common dominator. In fact if it ever were the code
fails to copy IDF to PRUNED_IDF, leading to wrong code.
The following fixes that by avoiding the copy and pruning from the
IDF in-place as well as using the more approprate check against
the single successor of the ENTRY_BLOCK.
* tree-into-ssa.cc (insert_updated_phi_nodes_for): Skip
pruning when the nearest common dominator is the successor
of ENTRY_BLOCK. Do not copy IDF but prune it directly.
The optimize_range_tests_to_bit_test optimization normally emits a range
test first:
if (entry_test_needed)
{
tem = build_range_check (loc, optype, unshare_expr (exp),
false, lowi, high);
if (tem == NULL_TREE || is_gimple_val (tem))
continue;
}
so during the bit test we already know that exp is in the [lowi, high]
range, but skips it if we have range info which tells us this isn't
necessary.
Also, normally it emits shifts by exp - lowi counter, but has an
optimization to use just exp counter if the mask isn't a more expensive
constant in that case and lowi is > 0 and high is smaller than prec.
The following testcase is miscompiled because the two abnormal cases
are triggered. The range of exp is [43, 43][48, 48][95, 95], so we on
64-bit arch decide we don't need the entry test, because 95 - 43 < 64.
And we also decide to use just exp as counter, because the range test
tests just for exp == 43 || exp == 48, so high is smaller than 64 too.
Because 95 is in the exp range, we can't do that, we'd either need to
do a range test first, i.e.
if (exp - 43U <= 48U - 43U) if ((1UL << exp) & mask1))
or need to subtract lowi from the shift counter, i.e.
if ((1UL << (exp - 43)) & mask2)
but can't do both unless r.upper_bound () is < prec.
The following patch ensures that.
2024-05-08 Jakub Jelinek <jakub@redhat.com>
PR tree-optimization/114965
* tree-ssa-reassoc.cc (optimize_range_tests_to_bit_test): Don't try to
optimize away exp - lowi subtraction from shift count unless entry
test is emitted or unless r.upper_bound () is smaller than prec.
* gcc.c-torture/execute/pr114965.c: New test.
This removes the last parameter of choose_multiplier, which is unused, adds
another assertion and more details to the description and various comments.
Likewise to the closely related invert_mod2n, except for the last parameter.
[changelog]
* expmed.h (choose_multiplier): Tweak description and remove last
parameter.
* expmed.cc (choose_multiplier): Likewise. Add assertion for the
third parameter and adds details to various comments.
(invert_mod2n): Tweak description and add assertion for the first
parameter.
(expand_divmod): Adjust calls to choose_multiplier.
* tree-vect-generic.cc (expand_vector_divmod): Likewise.
* tree-vect-patterns.cc (vect_recog_divmod_pattern): Likewise.
(if_then_else:SI (eq (reg:CCZ 17 flags)
(const_int 0 [0]))
(reg/v:SI 101 [ e ])
(reg:SI 102))
The cost is 8 for the rtx, the cost for
(eq (reg:CCZ 17 flags) (const_int 0 [0])) is 4,
but this is just an operator do not need to compute it's cost in cmov.
gcc/ChangeLog:
PR target/109549
* config/i386/i386.cc (ix86_rtx_costs): The XEXP (x, 0) for cmov
is an operator do not need to compute cost.
gcc/testsuite/ChangeLog:
* gcc.target/i386/cmov6.c: Fixed.
This throws the switch on prange. After this patch, it is no longer
valid to store a pointer in an irange (or vice versa). Instead, they
must go in prange, which is faster and more memory efficient.
I will push this now, so I have time to do any follow-up bugfixing
before going on paternity leave.
There are various cleanups we plan on doing after this patch (faster
intersect/union, remove range-op-mixed.h, remove value_range in favor
of int_range_max, reclaim the name for the Value_Range temporary,
clean up range-ops, etc etc). But we will hold off on those for now
to make it easier to revert this patch, if for some reason we need to
do so while I'm away.
Tested on x86-64 Linux.
gcc/ChangeLog:
* gimple-range-cache.cc (sbr_sparse_bitmap::sbr_sparse_bitmap):
Change irange to prange.
* gimple-range-fold.cc (fold_using_range::fold_stmt): Same.
(fold_using_range::range_of_address): Same.
* gimple-range-fold.h (range_of_address): Same.
* gimple-range-infer.cc (gimple_infer_range::add_nonzero): Same.
* gimple-range-op.cc (class cfn_strlen): Same.
* gimple-range-path.cc
(path_range_query::adjust_for_non_null_uses): Same.
* gimple-ssa-warn-access.cc (pass_waccess::check_pointer_uses): Same.
* tree-ssa-structalias.cc (find_what_p_points_to): Same.
* range-op-ptr.cc (range_op_table::initialize_pointer_ops): Remove
hybrid entries in table.
* range-op.cc (range_op_table::range_op_table): Add pointer
entries for bitwise and/or and min/max.
* value-range.cc (irange::verify_range): Add assert.
* value-range.h (irange::varying_compatible_p): Remove check for
error_mark_node.
(irange::supports_p): Remove pointer support.
* ipa-cp.h (ipa_supports_p): Add prange support.
In r14-9266-g2823b4d96d9ec4 I gave all temporary vars a DECL_CONTEXT,
including those at namespace or global scope, so that they could be
properly merged across importers. However, not all of these temporary
vars are actually supposed to be mergeable.
For instance, in the attached testcase we have an unnamed temporary var
used in the NSDMI of a class member, which cannot properly merged -- but
it also doesn't need to be, as it'll be thrown away when the class type
itself is merged anyway.
This patch reverts the change made above and instead makes a weaker
adjustment that only causes temporary vars with linkage have a
DECL_CONTEXT to merge from. This way these unnamed, "unmergeable"
temporaries are properly streamed by value again.
PR c++/114856
gcc/cp/ChangeLog:
* call.cc (make_temporary_var_for_ref_to_temp): Set context for
temporaries with linkage.
* init.cc (create_temporary_var): Revert to only set context
when in a function decl.
gcc/testsuite/ChangeLog:
* g++.dg/modules/pr114856.h: New test.
* g++.dg/modules/pr114856_a.H: New test.
* g++.dg/modules/pr114856_b.C: New test.
Signed-off-by: Nathaniel Shead <nathanieloshead@gmail.com>
Reviewed-by: Jason Merrill <jason@redhat.com>
Reviewed-by: Patrick Palka <ppalka@redhat.com>
After r7-987-gf17a223de829cb, the access for the elements of a vector type would lose the qualifiers.
So if we had `constvector[0]`, the type of the element of the array would not have const on it.
This was due to a missing build_qualified_type for the inner type of the vector when building the array type.
We need to add back the call to build_qualified_type and now the access has the correct qualifiers. So the
overloads and even if it is a lvalue or rvalue is correctly done.
Note we correctly now reject the testcase gcc.dg/pr83415.c which was incorrectly accepted after r7-987-gf17a223de829cb.
Built and tested for aarch64-linux-gnu.
PR c++/89224
gcc/c-family/ChangeLog:
* c-common.cc (convert_vector_to_array_for_subscript): Call build_qualified_type
for the inner type.
gcc/cp/ChangeLog:
* constexpr.cc (cxx_eval_array_reference): Compare main variants
for the vector/array types instead of the types directly.
gcc/testsuite/ChangeLog:
* g++.dg/torture/vector-subaccess-1.C: New test.
* gcc.dg/pr83415.c: Change warning to error.
Signed-off-by: Andrew Pinski <quic_apinski@quicinc.com>
In C++ sometimes you have a deconstructor function which is "empty", like for an
example with unions or with arrays. The front-end might not know it is empty either
so this should be done on during optimization.o
To implement it I added it to DCE where we mark if a statement is necessary or not.
Bootstrapped and tested on x86_64-linux-gnu with no regressions.
Changes since v1:
* v2: Add support for __aeabi_atexit for arm-*eabi. Add extra comments.
Add cxa_atexit-5.C testcase for -fPIC case.
* v3: Fix testcases for the __aeabi_atexit (forgot to do in the v2).
PR tree-optimization/19661
gcc/ChangeLog:
* tree-ssa-dce.cc (is_cxa_atexit): New function.
(is_removable_cxa_atexit_call): New function.
(mark_stmt_if_obviously_necessary): Don't mark removable
cxa_at_exit calls.
(mark_all_reaching_defs_necessary_1): Likewise.
(propagate_necessity): Likewise.
gcc/testsuite/ChangeLog:
* g++.dg/tree-ssa/cxa_atexit-1.C: New test.
* g++.dg/tree-ssa/cxa_atexit-2.C: New test.
* g++.dg/tree-ssa/cxa_atexit-3.C: New test.
* g++.dg/tree-ssa/cxa_atexit-4.C: New test.
* g++.dg/tree-ssa/cxa_atexit-5.C: New test.
* g++.dg/tree-ssa/cxa_atexit-6.C: New test.
Signed-off-by: Andrew Pinski <quic_apinski@quicinc.com>
This adds a few more of what is currently done in phiopt's value_replacement
to match. I noticed this when I was hooking up phiopt's value_replacement
code to use match and disabling the old code. But this can be done
independently from the hooking up phiopt's value_replacement as phiopt
is already hooked up for simplified versions already.
/* a != 0 ? a / b : 0 -> a / b iff b is nonzero. */
/* a != 0 ? a * b : 0 -> a * b */
/* a != 0 ? a & b : 0 -> a & b */
We prefer the `cond ? a : 0` forms to allow optimization of `a * cond` which
uses that form.
Bootstrapped and tested on x86_64-linux-gnu with no regressions.
PR tree-optimization/114894
gcc/ChangeLog:
* match.pd (`a != 0 ? a / b : 0`): New pattern.
(`a != 0 ? a * b : 0`): New pattern.
(`a != 0 ? a & b : 0`): New pattern.
gcc/testsuite/ChangeLog:
* gcc.dg/tree-ssa/phi-opt-value-5.c: New test.
Signed-off-by: Andrew Pinski <quic_apinski@quicinc.com>
Per quick email exchange with Palmer. Given the triviality, I'm just pushing
it.
gcc/
* config/riscv/riscv.cc (generic_ooo_tune_info): Turn on
overlap_op_by_pieces.
This is almost exclusively work from the VRULL team.
As we've discussed in the Tuesday meeting in the past, we'd like to have a knob
in the tuning structure to indicate that overlapped stores during
move_by_pieces expansion of memcpy & friends are acceptable.
This patch adds the that capability in our tuning structure. It's off for all
the uarchs upstream, but we have been using it inside Ventana for our uarch
with success. So technically it's NFC upstream, but puts in the infrastructure
multiple organizations likely need.
gcc/
* config/riscv/riscv.cc (struct riscv_tune_param): Add new
"overlap_op_by_pieces" field.
(rocket_tune_info, sifive_7_tune_info): Set it.
(sifive_p400_tune_info, sifive_p600_tune_info): Likewise.
(thead_c906_tune_info, xiangshan_nanhu_tune_info): Likewise.
(generic_ooo_tune_info, optimize_size_tune_info): Likewise.
(riscv_overlap_op_by_pieces): New function.
(TARGET_OVERLAP_OP_BY_PIECES_P): define.
gcc/testsuite/
* gcc.target/riscv/memcpy-nonoverlapping.c: New test.
* gcc.target/riscv/memset-nonoverlapping.c: New test.
The following patch imeplements the C++26 P2893R3 - Variadic friends
paper. The paper allows for the friend type declarations to specify
more than one friend type specifier and allows to specify ... at
the end of each. The patch doesn't introduce tentative parsing of
friend-type-declaration non-terminal, but rather just extends existing
parsing where it is a friend declaration which ends with ; after the
declaration specifiers to the cases where it ends with ...; or , or ...,
In that case it pedwarns for cxx_dialect < cxx26, handles the ... and
if there is , continues in a loop to parse the further friend type
specifiers.
2024-05-07 Jakub Jelinek <jakub@redhat.com>
PR c++/114459
gcc/c-family/
* c-cppbuiltin.cc (c_cpp_builtins): Predefine
__cpp_variadic_friend=202403L for C++26.
gcc/cp/
* parser.cc (cp_parser_member_declaration): Implement C++26
P2893R3 - Variadic friends. Parse friend type declarations
with ... or with more than one friend type specifier.
* friend.cc (make_friend_class): Allow TYPE_PACK_EXPANSION.
* pt.cc (instantiate_class_template): Handle PACK_EXPANSION_P
in friend classes.
gcc/testsuite/
* g++.dg/cpp26/feat-cxx26.C (__cpp_variadic_friend): Add test.
* g++.dg/cpp26/variadic-friend1.C: New test.
The HF and BF modes have the same size/precision and neither is
a subset nor superset of the other.
So, using either __extendhfbf2 or __trunchfbf2 is weird.
The expansion apparently emits __extendhfbf2, but on the libgcc side
we apparently have __trunchfbf2 implemented.
I think it is easier to switch to using what is available rather than
adding new entrypoints to libgcc, even alias, because this is backportable.
2024-05-07 Jakub Jelinek <jakub@redhat.com>
PR middle-end/114907
* expr.cc (convert_mode_scalar): Use trunc_optab rather than
sext_optab for HF->BF conversions.
* optabs-libfuncs.cc (gen_trunc_conv_libfunc): Likewise.
* gcc.dg/pr114907.c: New test.
In r9-5742 we've started allowing to inline always_inline functions into
functions which have disabled e.g. address sanitization even when the
always_inline function is implicitly from command line options sanitized.
This mostly works fine because most of the asan instrumentation is done only
late after ipa, but as the following testcase the .ASAN_MARK ifn calls
gimplifier adds can result in ICEs.
Fixed by dropping those during inlining, similarly to how we drop
.TSAN_FUNC_EXIT calls.
2024-05-07 Jakub Jelinek <jakub@redhat.com>
PR sanitizer/114956
* tree-inline.cc: Include asan.h.
(copy_bb): Remove also .ASAN_MARK calls if id->dst_fn has asan/hwasan
sanitization disabled.
* gcc.dg/asan/pr114956.c: New test.
This bug fix corrects the test codes below by converting the constant
literals to the type required by C. In the testcases below the values, 1
etc were converted into the INTEGER type before being passed to a C
vararg function. By default in modula2 constant literal ordinals are
represented as the ZTYPE (the largest GCC integer type node).
gcc/testsuite/ChangeLog:
PR modula2/114133
* gm2/extensions/run/pass/callingc10.mod: Convert constant
literal numbers into INTEGER.
* gm2/extensions/run/pass/callingc11.mod: Ditto.
* gm2/extensions/run/pass/vararg2.mod: Ditto.
* gm2/iso/run/pass/packed.mod: Emit a printf as a runtime
diagnostic.
Signed-off-by: Gaius Mulley <gaiusmod2@gmail.com>
So with Chrstoph's patches from late 2022 we've had the ability to inline
strlen, and str[n]cmp (scalar). However, we never actually turned this
capability on by default!
This patch flips the those default to allow inlinining by default. It also
fixes one bug exposed by our internal testing when NBYTES is zero for strncmp.
I don't think that case happens enough to try and optimize it, we just disable
inline expansion for that instance.
This has been bootstrapped and regression tested on rv64gc at various times as
well as cross tested on rv64gc more times than I can probably count (we've have
this patch internally for a while). More importantly, I just successfully
tested it on rv64gc and rv32gcv elf configurations with the trunk
gcc/
* config/riscv/riscv-string.cc (riscv_expand_strcmp): Do not inline
strncmp with zero size.
(emit_strcmp_scalar_compare_subword): Adjust rotation for rv32 vs rv64.
* config/riscv/riscv.opt (var_inline_strcmp): Enable by default.
(vriscv_inline_strncmp, riscv_inline_strlen): Likewise.
gcc/testsuite
* gcc.target/riscv/zbb-strlen-disabled-2.c: Turn off inlining.
Reuse MinGW definitions from i386 for libgcc. Move reused files to
libgcc/config/mingw folder.
libgcc/ChangeLog:
* config.host: Add aarch64-w64-mingw32 target. Adjust targets
after moving MinGW files.
* config/i386/t-gthr-win32: Move to...
* config/mingw/t-gthr-win32: ...here.
* config/i386/t-mingw-pthread: Move to...
* config/mingw/t-mingw-pthread: ...here.
* config/aarch64/t-no-eh: New file. EH is not yet implemented for
the target, and the default definition should be disabled.
Rename "x86 Windows Options" to "Cygwin and MinGW Options".
It will be used also for AArch64.
gcc/ChangeLog:
* config/i386/mingw-w64.opt.urls: Rename options' name and
regenerate option URLs.
* config/lynx.opt.urls: Likewise.
* config/mingw/cygming.opt.urls: Likewise.
* config/mingw/mingw.opt.urls: Likewise.
* doc/invoke.texi: Likewise.
SEH is not enabled in aarch64-w64-mingw32 target yet. However, it is
needed to be declared in machine_function for reusing winnt.cc.
gcc/ChangeLog:
* config/aarch64/aarch64.h (struct seh_frame_state): Declare SEH
structure in machine_function.
(GTY): Add SEH field.
Define Cygwin and MinGW environment such as types, SEH definitions,
shared libraries, etc.
gcc/ChangeLog:
* config.gcc: Add Cygwin and MinGW difinitions.
* config/aarch64/aarch64-protos.h
(mingw_pe_maybe_record_exported_symbol): Declare functions
which are used in Cygwin and MinGW environment.
(mingw_pe_section_type_flags): Likewise.
(mingw_pe_unique_section): Likewise.
(mingw_pe_encode_section_info): Likewise.
* config/aarch64/cygming.h: New file.
This patch defines TARGET_AARCH64_MS_ABI in config.gcc and uses it to
exclude i386 functionality from aarch64 build and adjust MinGW headers
for AArch64 MS ABI.
gcc/ChangeLog:
* config.gcc: Define TARGET_AARCH64_MS_ABI.
* config/mingw/mingw-stdint.h (INTPTR_TYPE): Use
TARGET_AARCH64_MS_ABI to adjust MinGW headers for
AArch64 MS ABI.
(UINTPTR_TYPE): Likewise.
(defined): Likewise.
* config/mingw/mingw32.h (DEFAULT_ABI): Likewise.
(defined): Likewise.
* config/mingw/winnt.cc (defined): Use TARGET_ARM64_MS_ABI to
exclude ix86_get_callcvt.
(i386_pe_maybe_mangle_decl_assembler_name): Likewise.
(i386_pe_mangle_decl_assembler_name): Likewise.
Define ASM specific for COFF format on AArch64.
gcc/ChangeLog:
* config.gcc: Add COFF format support definitions.
* config/aarch64/aarch64-coff.h: New file.
Define the MS ABI for aarch64-w64-mingw32.
Adjust FIXED_REGISTERS, CALL_REALLY_USED_REGISTERS and
STATIC_CHAIN_REGNUM for AArch64 MS ABI.
The X18 register is reserved on Windows for the TEB.
gcc/ChangeLog:
* config.gcc: Define TARGET_AARCH64_MS_ABI when
AArch64 MS ABI is used.
* config/aarch64/aarch64.h (FIXED_X18): Adjust
FIXED_REGISTERS, CALL_REALLY_USED_REGISTERS and
STATIC_CHAIN_REGNUM for AArch64 MS ABI.
(CALL_USED_X18): Likewise.
(FIXED_REGISTERS): Likewise.
* config/aarch64/aarch64-abi-ms.h: New file.
Add the initial aarch64-w64-mingw32 target for gcc.
This is the first commit in a sequence of patch series to add
new aarch64-w64-mingw32 target.
Coauthors: Zac Walker <zacwalker@microsoft.com>,
Mark Harmstone <mark@harmstone.com> and
Ron Riddle <ron.riddle@microsoft.com>
Refactored, prepared, and validated by
Radek Barton <radek.barton@microsoft.com> and
Evgeny Karpov <evgeny.karpov@microsoft.com>
fixincludes/ChangeLog:
* mkfixinc.sh: Extend for *-mingw32* targets.
gcc/ChangeLog:
* config.gcc: Add aarch64-w64-mingw32 target.
Eddie Nolan reported to me that _Unicode_view was not correctly
implementing the substitution of ill-formed subsequences with U+FFFD,
due to failing to increment the counter when the iterator reaches the
end of the sequence before a multibyte sequence is complete. As a
result, the incomplete sequence was not completely consumed, and then
the remaining character was treated as another ill-formed sequence,
giving two U+FFFD characters instead of one.
To avoid similar mistakes in future, this change introduces a lambda
that increments the iterator and the counter together. This ensures the
counter is always incremented when the iterator is incremented, so that
we always know how many characters have been consumed.
libstdc++-v3/ChangeLog:
* include/bits/unicode.h (_Unicode_view::_M_read_utf8): Ensure
count of characters consumed is correct when the end of the
input is reached unexpectedly.
* testsuite/ext/unicode/view.cc: Test incomplete UTF-8
sequences.
std::shared_ptr isn't declared for freestanding, so guard uses of it
with #if _GLIBCXX_HOSTED in <bits/out_ptr.h>.
libstdc++-v3/ChangeLog:
PR libstdc++/114866
* include/bits/out_ptr.h [!_GLIBCXX_HOSTED]: Don't refer to
shared_ptr, __shared_ptr or __is_shred_ptr.
* testsuite/20_util/headers/memory/114866.cc: New test.
The ldp/stp fusion pass can change the base of an access so that the two
accesses end up using a common base register. So far we have been using
adjust_address_nv to do this, but this means that we don't preserve
other properties of the mem we're replacing. It seems better to use
replace_equiv_address_nv, as this will preserve e.g. the MEM_ALIGN of the
mem whose address we're changing.
The PR shows that by adjusting the other mem we lose alignment
information about the original access and therefore end up rejecting an
otherwise viable pair when --param=aarch64-stp-policy=aligned is passed.
This patch fixes that by using replace_equiv_address_nv instead.
Notably this is the same approach as taken by
aarch64_check_consecutive_mems when a change of base is required, so
this at least makes things more consistent between the ldp fusion pass
and the peepholes.
gcc/ChangeLog:
PR target/114674
* config/aarch64/aarch64-ldp-fusion.cc (ldp_bb_info::fuse_pair):
Use replace_equiv_address_nv on a change of base instead of
adjust_address_nv on the other access.
gcc/testsuite/ChangeLog:
PR target/114674
* gcc.target/aarch64/pr114674.c: New test.
This replaces a >= 0 block index check with the appropriate NUM_FIXED_BLOCKs,
the check is from times ENTRY_BLOCK was negative.
* tree-into-ssa.cc (insert_updated_phi_nodes_for): Fix block
index check.
The following avoids re-allocating the var map BB vector by
pre-allocating it to the exact size needed when operating on the
whole function.
* tree-ssa-live.cc (init_var_map): Pre-allocate vec_bbs vector
to the correct size and use quick_push.
Implement the changes from P2944R3 which add constraints to the
comparison operators of std::pair, std::tuple, and std::variant.
The paper also changes std::optional, but we already constrain its
comparisons using SFINAE on the return type. However, we need some
additional constraints on the [optional.comp.with.t] operators that
compare an optional with a value. The paper doesn't say to do that, but
I think it's needed because otherwise when the comparison for two
optional objects fails its constraints, the two overloads that are
supposed to be for comparing to a non-optional become the best overload
candidates, but are ambiguous (and we don't even get as far as checking
the constraints for satisfaction). I reported LWG 4072 for this.
The paper does not change std::expected, but probably should have done.
I'll submit an LWG issue about that and implement it separately.
Also add [[nodiscard]] to all these comparison operators.
libstdc++-v3/ChangeLog:
* include/bits/stl_pair.h (operator==): Add constraint.
* include/bits/version.def (constrained_equality): Define.
* include/bits/version.h: Regenerate.
* include/std/optional: Define feature test macro.
(__optional_rep_op_t): Use is_convertible_v instead of
is_convertible.
* include/std/tuple: Define feature test macro.
(operator==, __tuple_cmp, operator<=>): Reimplement C++20
comparisons using lambdas. Add constraints.
* include/std/utility: Define feature test macro.
* include/std/variant: Define feature test macro.
(_VARIANT_RELATION_FUNCTION_TEMPLATE): Add constraints.
(variant): Remove unnecessary friend declarations for comparison
operators.
* testsuite/20_util/optional/relops/constrained.cc: New test.
* testsuite/20_util/pair/comparison_operators/constrained.cc:
New test.
* testsuite/20_util/tuple/comparison_operators/constrained.cc:
New test.
* testsuite/20_util/variant/relops/constrained.cc: New test.
* testsuite/20_util/tuple/comparison_operators/overloaded.cc:
Disable for C++20 and later.
* testsuite/20_util/tuple/comparison_operators/overloaded2.cc:
Remove dg-error line for target c++20.
libstdc++-v3/ChangeLog:
* include/backward/auto_ptr.h: Use https for URL in comment.
* include/bits/basic_ios.h: Likewise.
* include/std/iostream: Likewise.
If we update the list of "active" symbols versions now, rather than when
adding a new symbol version, we will notice if new symbols get added to
the wrong version (as in PR 114692).
libstdc++-v3/ChangeLog:
* testsuite/util/testsuite_abi.cc: Update latest versions to
new versions that should be used in future.
This avoids a tempoary when gimplifying reg = a ? b : c, re-using
the LHS of an assignment if that's a register.
PR middle-end/27800
* gimplify.cc (gimplify_modify_expr_rhs): For a COND_EXPR
avoid a temporary from gimplify_cond_expr when the LHS is
a register by pushing the assignment into the COND_EXPR arms.
* gcc.dg/pr27800.c: New testcase.
operand_equal_p already has checking code to verify the hash
is equal, avoid doing that again in gimplify_hasher::equal.
* gimplify.cc (gimplify_hasher::equal): Remove redundant
checking.
Bitcount operations popcount, clz, and ctz are emulated for narrow modes
in case an operation is only supported for wider modes. Beside that ctz
may be emulated via clz in expand_ctz. Reflect this in
expression_expensive_p.
I considered the emulation of ctz via clz as not expensive since this
basically reduces to ctz (x) = c - (clz (x & ~x)) where c is the mode
precision minus 1 which should be faster than a loop.
gcc/ChangeLog:
PR tree-optimization/110490
* tree-scalar-evolution.cc (expression_expensive_p): Also
consider mode widening for popcount, clz, and ctz.
We're currently using size_t but at the same time storing them into
bitmaps which only support unsigned int index. The following makes
it unsigned int throughout, saving memory as well.
* cfgexpand.cc (stack_var::representative): Use 'unsigned'
for stack var indexes instead of 'size_t'.
(stack_var::next): Likewise.
(EOC): Likewise.
(stack_vars_alloc): Likewise.
(stack_vars_num): Likewise.
(decl_to_stack_part): Likewise.
(stack_vars_sorted): Likewise.
(add_stack_var): Likewise.
(add_stack_var_conflict): Likewise.
(stack_var_conflict_p): Likewise.
(visit_op): Likewise.
(visit_conflict): Likewise.
(add_scope_conflicts_1): Likewise.
(stack_var_cmp): Likewise.
(part_hashmap): Likewise.
(update_alias_info_with_stack_vars): Likewise.
(union_stack_vars): Likewise.
(partition_stack_vars): Likewise.
(dump_stack_var_partition): Likewise.
(expand_stack_vars): Likewise.
(account_stack_vars): Likewise.
(stack_protect_decl_phase_1): Likewise.
(stack_protect_decl_phase_2): Likewise.
(asan_decl_phase_3): Likewise.
(init_vars_expansion): Likewise.
(estimated_stack_frame_size): Likewise.
TYPE_STRUCTURAL_EQUALITY_P is part of our type system so we have
to make sure to include that into the type unification done via
type_hash_canon. This requires the flag to be set before querying
the hash which is the biggest part of the patch.
PR middle-end/114931
gcc/
* tree.cc (type_hash_canon_hash): Hash TYPE_STRUCTURAL_EQUALITY_P.
(type_cache_hasher::equal): Compare TYPE_STRUCTURAL_EQUALITY_P.
(build_array_type_1): Set TYPE_STRUCTURAL_EQUALITY_P before
probing with type_hash_canon.
(build_function_type): Likewise.
(build_method_type_directly): Likewise.
(build_offset_type): Likewise.
(build_complex_type): Likewise.
* attribs.cc (build_type_attribute_qual_variant): Likewise.
gcc/c-family/
* c-common.cc (complete_array_type): Set TYPE_STRUCTURAL_EQUALITY_P
before probing with type_hash_canon.
gcc/testsuite/
* gcc.dg/pr114931.c: New testcase.
