git.libre-soc.org Git

ipa: fix bit CPP when combined with IPA bit CP

As mentioned in the PR, let's consider the following example:

int
__attribute__((noinline))
foo(int arg)
{
  if (arg == 3)
    return 1;
  if (arg == 4)
    return 123;

  __builtin_unreachable ();
}

during WPA we find all calls of the function
(yes the call with value 5 is UBSAN):

  Node: foo/0:
    param [0]: 5 [loc_time: 4, loc_size: 2, prop_time: 0, prop_size: 0]
               3 [loc_time: 3, loc_size: 3, prop_time: 0, prop_size: 0]
         ctxs: VARIABLE
         Bits: value = 0x5, mask = 0x6

in LTRANS we have the following VRP info:

  # RANGE [3, 3] NONZERO 3

when we AND masks in get_default_value we end up with 6 & 3 = 2 (0x010).
That means the only second (least significant bit) is unknown and
value (5 = 0x101) & ~mask gives us either 7 (0x111) or 5 (0x101).

That's why if (arg_2(D) == 3) gets optimized to false.

gcc/ChangeLog:

PR ipa/96482
* ipa-cp.c (ipcp_bits_lattice::meet_with_1): Drop value bits
for bits that are unknown.
(ipcp_bits_lattice::set_to_constant): Likewise.
* tree-ssa-ccp.c (get_default_value): Add sanity check that
IPA CP bit info has all bits set to zero in bits that
are unknown.

gcc/testsuite/ChangeLog:

PR ipa/96482
* gcc.dg/ipa/pr96482.c: New test.

AArch64: Add if condition in aarch64_function_value [PR96479]

Report diagnostic information instead of ICE if it generats fp/simd for
return register when fp/simd is disabled by -mgeneral-regs-only.

gcc/ChangeLog:

* config/aarch64/aarch64.c (aarch64_function_value): Add if
condition to check ag_mode after entering if condition of
aarch64_vfp_is_call_or_return_candidate. If TARGET_FLOAT is
set as false by -mgeneral-regs-only, report the diagnostic
information of -mgeneral-regs-only imcompatible with the use
of fp/simd register(s).

gcc/testsuite/ChangeLog:

* gcc.target/aarch64/mgeneral-regs_1.c: Add the comment that
-mgeneral-regs-only is compatible with the use of vector type
used in the test case.

Fortran: Add support for OpenMP's nontemporal clause

gcc/fortran/ChangeLog:

* gfortran.h: Add OMP_LIST_NONTEMPORAL.
* dump-parse-tree.c (show_omp_clauses): Dump it
* openmp.c (enum omp_mask1): Add OMP_CLAUSE_NOTEMPORAL.
(OMP_SIMD_CLAUSES): Add it.
(gfc_match_omp_clauses): Match nontemporal clause.
* trans-openmp.c (gfc_trans_omp_clauses): Process
nontemporal clause.

gcc/testsuite/ChangeLog:

* gfortran.dg/gomp/nontemporal-1.f90: New test.
* gfortran.dg/gomp/nontemporal-2.f90: New test.

Fix up flag_cunroll_grow_size handling in presence of optimize attr [PR96535]

As the testcase in the PR shows (not included in the patch, as
it seems quite fragile to observe unrolling in the IL), the introduction of
flag_cunroll_grow_size broke optimize attribute related to loop unrolling.
The problem is that the new option flag is set (if not set explicitly) only
in process_options and in rs6000_option_override_internal (and there only if
global_init_p).  So, this means that while it is Optimization option, it
will only be set based on the command line -funroll-loops/-O3/-fpeel-loops
or -funroll-all-loops, which means that if command line does include any of
those, it is enabled even for functions that will through optimize attribute
have all of those disabled, and if command line does not include those,
it will not be enabled for functions that will through optimize attribute
have any of those enabled.

process_options is called just once, so IMHO it should be handling only
non-Optimization option adjustments (various other options suffer from that
too, but as this is a regression from 10.1 on the 10 branch, changing those
is not appropriate).  Similarly, rs6000_option_override_internal is called
only once (with global_init_p) and then for target attribute handling, but
not for optimize attribute handling.

This patch moves the unrolling related handling from process_options into
finish_options which is invoked whenever the options are being finalized,
and the rs6000 specific parts into the override_options_after_change hook
which is called for optimize attribute handling (and unfortunately also
th cfun changes, but what the hook does is cheap) and I've added a call to
that from rs6000_override_options_internal, so it is also called on cmdline
processing and for target attribute.

Furthermore, it stops using AUTODETECT_VALUE, which can work only once,
and instead uses the global_options_set.x_... flags.

2020-08-12  Jakub Jelinek  <jakub@redhat.com>

PR tree-optimization/96535
* toplev.c (process_options): Move flag_unroll_loops and
flag_cunroll_grow_size handling from here to ...
* opts.c (finish_options): ... here.  For flag_cunroll_grow_size,
don't check for AUTODETECT_VALUE, but instead check
opts_set->x_flag_cunroll_grow_size.
* common.opt (funroll-completely-grow-size): Default to 0.
* config/rs6000/rs6000.c (TARGET_OVERRIDE_OPTIONS_AFTER_CHANGE):
Redefine.
(rs6000_override_options_after_change): New function.
(rs6000_option_override_internal): Call it.  Move there the
flag_cunroll_grow_size, unroll_only_small_loops and
flag_rename_registers handling.

[testsuite, nvptx] Borrow ia64-sync-*.c test-cases in gcc.target/nvptx

In absence of nvptx-enabling for effective target sync_int_long (see PR96494),
copy a few test-cases to gcc.target/nvptx.

Tested on nvptx.

gcc/testsuite/ChangeLog:

* gcc.target/nvptx/ia64-sync-1.c: New test.
* gcc.target/nvptx/ia64-sync-2.c: New test.
* gcc.target/nvptx/ia64-sync-3.c: New test.
* gcc.target/nvptx/ia64-sync-4.c: New test.

Fix gcc.dg/ia64-sync-5.c for architectures with unsigned char as default (PR 96519)

If char is unsigned, then comparisons of the char array elements against
negative integers in the test will fail as values in the array will always
be positive, and will remain so when promoted to signed int.

2020-08-12 Kwok Cheung Yeung <kcy@codesourcery.com>

PR testsuite/96519

gcc/testsuite/
* gcc.dg/ia64-sync-5.c (AC, init_qi, test_qi): Change element type to
signed char.

[testsuite] Add effective target large_initializer

When compiling builtin-object-size-21.c for nvptx, cc1 times out while
emitting the initializer for global variable xm3_3.

With x86_64, we are able to emit the initializer with a few lines of assembly:
...
xm3_3:
        .byte   0
        .zero   9223372036854775803
        .byte   1
        .byte   2
        .byte   3
...
but with nvptx, we don't have some something similar available, and thus
generate:
...
  .visible .global .align 1 .u32 xm3_3[2305843009213693952] =
  { 0, 0, 0, ...
...

Introduce an effective target large_initializer, returning false for nvptx,
and require it for test-cases with large initializers.

Tested on nvptx with make check-gcc.

gcc/testsuite/ChangeLog:

PR testsuite/96566
* lib/target-supports.exp (check_effective_target_large_initializer):
New proc.
* gcc.dg/builtin-object-size-21.c: Require large_initializer.
* gcc.dg/strlenopt-55.c: Same.

[nvptx] Fix array dimension in nvptx_assemble_decl_begin

When compiling test-case builtin-object-size-21.c, cc1 emits:
...
  .visible .global .align 1 .u32 xm3_3[-2305843009213693951] =
...
for:
...
struct Ax_m3 { char a[PTRDIFF_MAX - 3], ax[]; };

struct Ax_m3 xm3_3 = { { 0 }, { 1, 2, 3 } };
...

Fix this by:
- changing the printing format for unsigned HOST_WIDE_INT init_frag.remaining
  to HOST_WIDE_INT_PRINT_UNSIGNED
- changing the type of local variable elt_size in nvptx_assemble_decl_begin
  to unsigned HOST_WIDE_INT.
such that we have:
...
  .visible .global .align 1 .u32 xm3_3[2305843009213693952] =
...
where 2305843009213693952 == 0x2000000000000000, so the array is claiming
0x8000000000000000 bytes, which is one more than PTRDIFF_MAX.  This is due
to using .u32 instead of .u8, so strictly speaking we should downgrade to
using .u8 in this case, but that corner-case problem doesn't look urgent
enough to fix in this commit.

Build on nvptx, tested with make check-gcc.

gcc/ChangeLog:

* config/nvptx/nvptx.c (nvptx_assemble_decl_begin): Make elt_size an
unsigned HOST_WIDE_INT.  Print init_frag.remaining using
HOST_WIDE_INT_PRINT_UNSIGNED.

MAINTAINERS: Update my email address

2020-08-12 Senthil Kumar Selvaraj <saaadhu@gcc.gnu.org>

* MAINTAINERS: Update my email address.

testsuite: Fix gcc.target/arm/stack-protector-1.c for Cortex-M

The stack-protector-1.c test fails when compiled for Cortex-M:
- for Cortex-M0/M1, str r0, [sp #-8]! is not supported
- for Cortex-M3/M4..., the assembler complains that "use of r13 is
  deprecated"

This patch replaces the str instruction with
     sub   sp, sp, #8
     str r0, [sp]
and removes the check for r13, which is unlikely to leak the canary
value.

2020-08-11  Christophe Lyon  <christophe.lyon@linaro.org>

gcc/testsuite/
* gcc.target/arm/stack-protector-1.c: Adapt code to Cortex-M
restrictions.

testsuite: Fix gcc.target/arm/multilib.exp use of gcc_opts

This patch fixes an incorrect parameter passing for $gcc_opts, which
produces a DejaGnu error: (DejaGnu) proc "gcc_opts" does not exist.

2020-08-12 Christophe Lyon <christophe.lyon@linaro.org>

gcc/testsuite/
* gcc.target/arm/multilib.exp: Fix parameter passing for gcc_opts.

x86_64: Use peephole2 to eliminate redundant moves.

The recent fix for mul_widen_cost revealed an interesting
quirk of ira/reload register allocation on x86_64.  As shown in
https://gcc.gnu.org/pipermail/gcc-patches/2020-August/551648.html
for gcc.target/i386/pr71321.c we generate the following code that
performs unnecessary register shuffling.

        movl    $-51, %edx
        movl    %edx, %eax
        mulb    %dil

Various discussions in bugzilla seem to point to reload preferring
not to load constants directly into CLASS_LIKELY_SPILLED_P registers.
Whatever the cause, one solution (workaround), that doesn't involve
rewriting a register allocator, is to use peephole2 to spot this
wierdness and eliminate it.  With this peephole2 the above three
instructions (from pr71321.c) are replaced with:

        movl    $-51, %eax
        mulb    %dil

2020-08-12  Roger Sayle  <roger@nextmovesoftware.com>
    Uroš Bizjak  <ubizjak@gmail.com>

gcc/ChangeLog
* config/i386/i386.md (peephole2): Reduce unnecessary
register shuffling produced by register allocation.

Replace std::vector<> usage in ipa-fnsummary.c with GCC's vec<>.

gcc/ChangeLog:

* ipa-fnsummary.c (evaluate_conditions_for_known_args): Use vec<>
instead of std::vector<>.
(evaluate_properties_for_edge): Same.
(ipa_fn_summary_t::duplicate): Same.
(estimate_ipcp_clone_size_and_time): Same.
* vec.h (<T, A, vl_embed>::embedded_size): Change vec_embedded
type to contain a char[].

IBM Z: Fix PR96308

For the testcase a symbol with a TLS reloc and an unary minus is being
generated. The backend didn't handle this correctly.

In s390_cannot_force_const_mem an unary minus on a symbolic constant
is rejected now since gas would not allow this.

legitimize_tls_address now makes the NEG rtx the outermost operation
by pulling it out of the CONST rtx.

gcc/ChangeLog:

PR target/96308
* config/s390/s390.c (s390_cannot_force_const_mem): Reject an
unary minus for everything not being a numeric constant.
(legitimize_tls_address): Move a NEG out of the CONST rtx.

gcc/testsuite/ChangeLog:

PR target/96308
* g++.dg/pr96308.C: New test.

IBM Z: Fix PR96456

The testcase failed because our backend refuses to generate vector
compare instructions for signaling operators with -fno-trapping-math
-fno-finite-math-only.

gcc/ChangeLog:

PR target/96456
* config/s390/s390.h (TARGET_NONSIGNALING_VECTOR_COMPARE_OK): New
macro.
* config/s390/vector.md (vcond_comparison_operator): Use new macro
for the check.

gcc/testsuite/ChangeLog:

PR target/96456
* gcc.target/s390/pr96456.c: New test.

Re: PR96493, powerpc local call linkage failure

PR target/96525
* gcc.target/powerpc/pr96493.c: Make it a link test when no
power10_hw. Require power10_ok.

Daily bump.

libstdc++: Implement DR 526 on [forward_]list remove_if/unique [PR 91620]

Respect DR 526 in implementation of std::[forward_]list remove/remove_if/unique.
[forward_]list::remove was already implementing it but the implementation has
been modified to generalize the following pattern. All nodes to remove are
collected in an intermediate [forward_]list which purpose is just to be
detroyed once out of scope.

libstdc++-v3/ChangeLog:

PR libstdc++/91620
* include/bits/forward_list.tcc (forward_list<>::remove): Collect nodes
to destroy in an intermediate forward_list.
(forward_list<>::remove_if, forward_list<>::unique): Likewise.
* include/bits/list.tcc (list<>::remove, list<>::unique): Likewise.
(list<>::remove_if): Likewise.
* include/debug/forward_list (forward_list<>::_M_erase_after): Remove.
(forward_list<>::erase_after): Adapt.
(forward_list<>::remove, forward_list<>::remove_if): Collect nodes to
destroy in an intermediate forward_list.
(forward_list<>::unique): Likewise.
* include/debug/list (list<>::remove, list<>::unique): Likewise.
(list<>::remove_if): Likewise.
* testsuite/23_containers/forward_list/operations/91620.cc: New test.
* testsuite/23_containers/list/operations/91620.cc: New test.

internal/syscall/unix: restore ppc build tag

It was accidentally lost in the 1.15rc1 merge.

Fixes PR go/96567

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/247843

testsuite: remove xfail flifetime-dse[24].C

The testcases no longer are failing due to operator new, so
remove the xfails to reduce testsuite summary noise.

gcc/testsuite/ChangeLog:

2020-08-11 David Edelsohn <dje.gcc@gmail.com>

* g++.dg/opt/flifetime-dse2.C: Remove AIX xfail.
* g++.dg/opt/flifetime-dse4.C: Remove AIX xfail.

[testsuite] Add missing require-effective-target directives in gcc.dg

Add some missing require-effect-targets directives (alloca, indirect_jumps,
label_values and nonlocal_goto).

Tested on nvptx.

gcc/testsuite/ChangeLog:

* gcc.dg/Warray-bounds-46.c: Add missing require-effective-target
directive.
* gcc.dg/Warray-bounds-48.c: Same.
* gcc.dg/Warray-bounds-50.c: Same.
* gcc.dg/Wreturn-local-addr-2.c: Same.
* gcc.dg/Wreturn-local-addr-3.c: Same.
* gcc.dg/Wreturn-local-addr-4.c: Same.
* gcc.dg/Wreturn-local-addr-6.c: Same.
* gcc.dg/Wstack-usage.c: Same.
* gcc.dg/Wstringop-overflow-15.c: Same.
* gcc.dg/Wstringop-overflow-23.c: Same.
* gcc.dg/Wstringop-overflow-25.c: Same.
* gcc.dg/Wstringop-overflow-27.c: Same.
* gcc.dg/Wstringop-overflow-39.c: Same.
* gcc.dg/analyzer/alloca-leak.c: Same.
* gcc.dg/analyzer/data-model-1.c: Same.
* gcc.dg/analyzer/data-model-16.c: Same.
* gcc.dg/analyzer/malloc-1.c: Same.
* gcc.dg/analyzer/malloc-paths-8.c: Same.
* gcc.dg/analyzer/pr93546.c: Same.
* gcc.dg/analyzer/setjmp-1.c: Same.
* gcc.dg/analyzer/setjmp-2.c: Same.
* gcc.dg/analyzer/setjmp-3.c: Same.
* gcc.dg/analyzer/setjmp-4.c: Same.
* gcc.dg/analyzer/setjmp-5.c: Same.
* gcc.dg/analyzer/setjmp-6.c: Same.
* gcc.dg/analyzer/setjmp-7.c: Same.
* gcc.dg/analyzer/setjmp-7a.c: Same.
* gcc.dg/analyzer/setjmp-8.c: Same.
* gcc.dg/analyzer/setjmp-9.c: Same.
* gcc.dg/analyzer/setjmp-pr93378.c: Same.
* gcc.dg/gimplefe-44.c: Same.
* gcc.dg/pr84131.c: Same.
* gcc.dg/pr93986.c: Same.
* gcc.dg/pr95133.c: Same.
* gcc.dg/pr95857.c: Same.
* gcc.dg/strlenopt-83.c: Same.
* gcc.dg/strlenopt-84.c: Same.
* gcc.dg/strlenopt-91.c: Same.
* gcc.dg/uninit-32.c: Same.
* gcc.dg/uninit-36.c: Same.

libstdc++: Fix failing tests for AIX

These two tests fail on AIX because <sys/thread.h> defines struct thread
in the global namespace (despite it not being a reserved name). That
means the using-declaration that adds it to the global namespace causes
a redeclaration error.

libstdc++-v3/ChangeLog:

* testsuite/30_threads/thread/cons/84535.cc: Use a custom
namespace.
* testsuite/30_threads/thread/cons/lwg2097.cc: Likewise.

libstdc++: Make Networking TS work without gthreads [PR 89760]

Make the experimental Networking TS code work without std::mutex and
std::condition_variable.

libstdc++-v3/ChangeLog:

PR libstdc++/89760
* include/experimental/executor [!_GLIBCXX_HAS_GTHREADS]:
(execution_context::mutex_type): Define dummy mutex type.
(system_context): Use execution_context::mutex_type.
(system_context) [!_GLIBCXX_HAS_GTHREADS]: Define dummy
thread and condition variable types.
[!_GLIBCXX_HAS_GTHREADS] (system_context::_M_run()): Do not
define.
(system_context::_M_post) [!_GLIBCXX_HAS_GTHREADS]: Throw
an exception when threads aren't available.
(strand::running_in_this_thread()): Defer to _M_state.
(strand::_State::running_in_this_thread()): New function.
(use_future_t): Do not depend on _GLIBCXX_USE_C99_STDINT_TR1.
* include/experimental/io_context (io_context): Use the
execution_context::mutex_type alias. Replace stack of thread
IDs with counter.
* testsuite/experimental/net/execution_context/use_service.cc:
Enable test for non-pthread targets.

libstdc++: Make net::system_context tag type constructor explicit

libstdc++-v3/ChangeLog:

* include/experimental/executor (system_context::a__tag): Make
default constructor explicit.

libstdc++: Fix net::system_context stop condition

libstdc++-v3/ChangeLog:

* include/experimental/executor (system_context::_M_run()):
Fix predicate.
* testsuite/experimental/net/system_context/1.cc: New test.

libstdc++: Fix <stop_token> to compile without gthreads

libstdc++-v3/ChangeLog:

* include/std/stop_token: Check _GLIBCXX_HAS_GTHREADS using
#ifdef instead of #if.
(stop_token::_S_yield()): Check _GLIBCXX_HAS_GTHREADS before
using __gthread_yield.

libstdc++: Make std::this_thread functions work without gthreads

The only function in namespace std::this_thread that actually depends on
thread support being present is this_thread::get_id(). The other
functions (yield, sleep_for and sleep_until) can be defined for targets
without gthreads.

A small change is needed in std::this_thread::sleep_for which currently
uses the __gthread_time_t typedef. Since it just calls nanosleep
directly, it should use timespec directly instead of the typedef.

Even std::this_thread::get_id() could be made to work, the only
difficulty is that it returns a value of type std::thread::id and
std::thread is only defined when gthreads support exists.

libstdc++-v3/ChangeLog:

* include/std/thread [!_GLIBCXX_HAS_GTHREADS] (this_thread::yield)
(this_thread::sleep_until): Define.
[!_GLIBCXX_HAS_GTHREADS] (this_thread::sleep_for): Define. Replace
use of __gthread_time_t typedef with timespec.
* src/c++11/thread.cc [!_GLIBCXX_HAS_GTHREADS] (__sleep_for):
Likewise.
* testsuite/30_threads/this_thread/2.cc: Moved to...
* testsuite/30_threads/this_thread/yield.cc: ...here.
* testsuite/30_threads/this_thread/3.cc: Moved to...
* testsuite/30_threads/this_thread/sleep_for-mt.cc: ...here.
* testsuite/30_threads/this_thread/4.cc: Moved to...
* testsuite/30_threads/this_thread/sleep_until-mt.cc: ...here.
* testsuite/30_threads/this_thread/58038.cc: Add
dg-require-sleep.
* testsuite/30_threads/this_thread/60421.cc: Likewise.
* testsuite/30_threads/this_thread/sleep_for.cc: New test.
* testsuite/30_threads/this_thread/sleep_until.cc: New test.

c-family: Fix ICE in get_atomic_generic_size [PR96545]

As the testcase shows, we would ICE if the type of the first argument of
various atomic builtins was pointer to (non-void) incomplete type, we would
assume that TYPE_SIZE_UNIT must be non-NULL.  This patch diagnoses it
instead.  And also changes the TREE_CODE != INTEGER_CST check to
!tree_fits_uhwi_p, as we use tree_to_uhwi after this and at least in theory
the int could be too large and not fit.

2020-08-11  Jakub Jelinek  <jakub@redhat.com>

PR c/96545
* c-common.c (get_atomic_generic_size): Require that first argument's
type points to a complete type and use tree_fits_uhwi_p instead of
just INTEGER_CST TREE_CODE check for the TYPE_SIZE_UNIT.

* c-c++-common/pr96545.c: New test.

expr: Optimize noop copies [PR96539]

At GIMPLE e.g. for __builtin_memmove we optimize away (to just the return
value) noop copies where src == dest, but at the RTL we don't, and as the
testcase shows, in some cases such copies can appear only at the RTL level
e.g. from trying to copy an aggregate by value argument to the same location
as it already has. If the block move is expanded e.g. piecewise, we
actually manage to optimize it away, as the individual memory copies are
seen as noop moves, but if the target optabs are used, often the sequences
stay until final.

2020-08-11 Jakub Jelinek <jakub@redhat.com>

PR rtl-optimization/96539
* expr.c (emit_block_move_hints): Don't copy anything if x and y
are the same and neither is MEM_VOLATILE_P.

* gcc.target/i386/pr96539.c: New test.

tree: Fix up get_narrower [PR96549]

My changes to get_narrower to support COMPOUND_EXPRs apparently
used a wrong type for the COMPOUND_EXPRs, while e.g. the rhs
type was unsigned short, the COMPOUND_EXPR got int type as that was the
original type of op. The type of COMPOUND_EXPR should be always the type
of the rhs.

2020-08-11 Jakub Jelinek <jakub@redhat.com>

PR c/96549
* tree.c (get_narrower): Use TREE_TYPE (ret) instead of
TREE_TYPE (win) for COMPOUND_EXPRs.

* gcc.c-torture/execute/pr96549.c: New test.

Do not combine PRED_LOOP_GUARD and PRED_LOOP_GUARD_WITH_RECURSION

This patch avoids both PRED_LOOP_GUARD and PRED_LOOP_GUARD_WITH_RECURSION to be
attached to one edge.  We have logic that prevents same predictor to apply to
one edge twice, but since we split LOOP_GUARD to two more specialized cases,
this no longer fires.

Double prediction happens in exchange benchmark and leads to unrealistically
low hitrates on some edges which in turn leads to bad IPA profile and misguides
ipa-cp.

Unforutnately it seems that the bad profile also leads to bit better
performance by disabling some of loop stuff, but that really ought to be done
in some meaningful way, not by an accident.

gcc/ChangeLog:

2020-08-11  Jan Hubicka  <hubicka@ucw.cz>

* predict.c (not_loop_guard_equal_edge_p): New function.
(maybe_predict_edge): New function.
(predict_paths_for_bb): Use it.
(predict_paths_leading_to_edge): Use it.

gcc/testsuite/ChangeLog:

2020-08-11  Jan Hubicka  <hubicka@ucw.cz>

* gcc.dg/ipa/ipa-clone-2.c: Lower threshold from 500 to 400.

Add debug counter for IPA bits CP.

gcc/ChangeLog:

* dbgcnt.def (DEBUG_COUNTER): Add ipa_cp_bits.
* ipa-cp.c (ipcp_store_bits_results): Use it when we store known
bits for parameters.

Daily bump.

c++: Add unfixed test [PR88003]

Now that dg-ice is available, let's try it out.

gcc/testsuite/ChangeLog:

PR c++/88003
* g++.dg/cpp1y/auto-fn61.C: New test.

runtime: revert eqtype for AIX

AIX linker is not able to merge identical type descriptors in a single
symbol if there are coming from different object or shared object files.
This results into several pointers referencing the same type
descriptors.
Thus, eqtype is needed to ensure that these different symbols will be
considered as the same type descriptor.

Fixes golang/go#39276

gcc/go/ChangeLog:

* go-c.h (struct go_create_gogo_args): Add need_eqtype field.
* go-lang.c (go_langhook_init): Set need_eqtype.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/235697

testsuite: Introduce dg-ice.

This patch adds a new DejaGNU directive, dg-ice, as outlined in the
proposal here:
https://gcc.gnu.org/pipermail/gcc-patches/2020-July/550913.html

It means that it's expected that the compiler crashes with an internal
compiler error when compiling test with such a directive.

A minor optimization could be to use -pass-exit-codes and then check for
ICE_EXIT_CODE return code instead of using string match.

gcc/ChangeLog:

* doc/sourcebuild.texi: Document dg-ice.

gcc/testsuite/ChangeLog:

* lib/gcc-dg.exp (gcc-dg-test-1): Handle dg-ice.
(cleanup-after-saved-dg-test): Reset expect_ice.
* lib/prune.exp (prune_ices): New.
* lib/target-supports-dg.exp (dg-ice): New.

i386: Improve code generation of smin(x,0) with -m32.

To make amends for the recent (temporary) testsuite failure
of my new gcc.target/i386/minmax-9.c when compiled with -m32,
this patch improves the -m32 code we generate for the examples
in that test case.

The trick is to expand smin(x,0) as "x < 0 ? x : 0" instead
of the current "x <= 0 ? x : 0", as the former can take
advantage of sign_bit_mask operations.

2020-08-10 Roger Sayle <roger@nextmovesoftware.com>

gcc/ChangeLog
* config/i386/i386-expand.c (ix86_expand_int_movcc): Expand
signed MIN_EXPR against zero as "x < 0 ? x : 0" instead of
"x <= 0 ? x : 0" to enable sign_bit_compare_p optimizations.

gcc/testsuite/ChangeLog
* gcc.target/i386/minmax-12.c: New test.

libstdc++: Fix build for targets without lstat [PR 94681]

libstdc++-v3/ChangeLog:

PR libstdc++/94681
* src/c++17/fs_ops.cc (read_symlink): Use posix::lstat instead
of calling ::lstat directly.
* src/filesystem/ops.cc (read_symlink): Likewise.

libstdc++: Fix compatibility support in unique_ptr pretty printer

The support for the old std::unique_ptr implementation was failing,
because it tried to work on a typedef instead of the underlying type.
The test supposed to verify the support worked wasn't using a typedef,
so didn't notice the problem.

libstdc++-v3/ChangeLog:

* python/libstdcxx/v6/printers.py (UniquePointerPrinter.__init__):
Use gdb.Type.strip_typedefs().
* testsuite/libstdc++-prettyprinters/compat.cc: Use a typedef in
the emulated old type.

Fix NULL pointer dereference in doloop_contained_function_call.

gcc/fortran/ChangeLog:

PR fortran/96556
* frontend-passes.c (doloop_contained_function_call):
Do not dereference a NULL pointer for value.function.esym.

gcc/testsuite/ChangeLog:

PR fortran/96556
* gfortran.dg/do_check_15.f90: New test.

c++: Fix constexpr evaluation of SPACESHIP_EXPR [PR96497]

The following valid testcase is rejected, because cxx_eval_binary_expression
is called on the SPACESHIP_EXPR with lval = true, as the address of the
spaceship needs to be passed to a method call.
After recursing on the operands and calling genericize_spaceship which turns
it into a TARGET_EXPR with initialization, we call cxx_eval_constant_expression
on it which succeeds, but then we fall through into code that will
VERIFY_CONSTANT (r) which FAILs because it is an address of a variable. Rather
than avoiding that for lval = true and SPACESHIP_EXPR, the patch just tail
calls cxx_eval_constant_expression - I believe that call should perform all
the needed verifications.

2020-08-10 Jakub Jelinek <jakub@redhat.com>

PR c++/96497
* constexpr.c (cxx_eval_binary_expression): For SPACESHIP_EXPR, tail
call cxx_eval_constant_expression after genericize_spaceship to avoid
undesirable further VERIFY_CONSTANT.

* g++.dg/cpp2a/spaceship-constexpr3.C: New test.

c++: constraints and address of template-id

When resolving the address of a template-id, we need to drop functions
whose associated constraints are not satisfied, as per [over.over]. We
do so in resolve_address_of_overloaded_function, but not in
resolve_overloaded_unification or resolve_nondeduced_context, which
seems like an oversight.

gcc/cp/ChangeLog:

* pt.c (resolve_overloaded_unification): Drop functions with
unsatisfied constraints.
(resolve_nondeduced_context): Likewise.

gcc/testsuite/ChangeLog:

* g++.dg/cpp2a/concepts-fn5.C: New test.
* g++.dg/concepts/fn8.C: Generalize dg-error directive to accept
"no matching function ..." diagnostic.
* g++.dg/cpp2a/concepts-fn1.C: Likewise.
* g++.dg/cpp2a/concepts-ts2.C: Likewise.
* g++.dg/cpp2a/concepts-ts3.C: Likewise.

libstdc++: Make C++17 ignore --disable-libstdcxx-filesystem-ts [PR 94681]

The configure switch should only affect the optional Filesystem TS, not
the std::filesystem features of C++17.

libstdc++-v3/ChangeLog:

PR libstdc++/94681
* acinclude.m4 (GLIBCXX_CHECK_FILESYSTEM_DEPS): Do not depend on
$enable_libstdcxx_filesystem_ts.
* configure: Regenerate.

libstdc++: Implement LWG 561 for std::inserter

libstdc++-v3/ChangeLog:

* include/bits/stl_iterator.h (inserter): Do not deduce
iterator type (LWG 561).
* testsuite/24_iterators/insert_iterator/dr561.cc: New test.

libstdc++: Check __cpp_exceptions in basic_string::reserve()

If exceptions are disabled then reallocating could abort, so ignore
shrink-to-fit requests.

libstdc++-v3/ChangeLog:

* include/bits/basic_string.tcc [_GLIBCXX_USE_CXX11_ABI=0]
(basic_string::reserve()): Do nothing if exceptions are not
enabled.

Declare gt_* functions inline in value-range.h.

gcc/ChangeLog:

* value-range.h (gt_ggc_mx): Declare inline.
(gt_pch_nx): Same.

Simplify X * C1 == C2 with wrapping overflow

Odd numbers are invertible in Z / 2^n Z, so X * C1 == C2 can be rewritten
as X == C2 * inv(C1) when overflow wraps.

mod_inv should probably be updated to better match the other wide_int
functions, but that's a separate issue.

2020-08-10 Marc Glisse <marc.glisse@inria.fr>

PR tree-optimization/95433
* match.pd (X * C1 == C2): Handle wrapping overflow.
* expr.c (maybe_optimize_mod_cmp): Qualify call to mod_inv.
(mod_inv): Move...
* wide-int.cc (mod_inv): ... here.
* wide-int.h (mod_inv): Declare it.

* gcc.dg/tree-ssa/pr95433-2.c: New file.

libstdc++: Use _wstat64 for Windows [PR 95749]

In order to handle large files on Windows we need to use stat API with
64-bit st_sioze member.

libstdc++-v3/ChangeLog:

PR libstdc++/95749
* src/filesystem/ops-common.h [_GLIBCXX_FILESYSTEM_IS_WINDOWS]
(stat_type): Change to __wstat64.
(stat): Use _wstat64.

Fix remove_predictions_associated_with_edge

remove_predictions_associated_with_edge currently calls filter_predicitons
passing it equal_edge_p. Becase filter_predictions removes all edges where
filter returns false, the function does exact oposite. Fixed thus.

Bootstrapped/regtested x86_64-linux.

gcc/ChangeLog:

2020-08-02 Jan Hubicka <hubicka@ucw.cz>

* predict.c (filter_predictions): Document semantics of filter.
(equal_edge_p): Rename to ...
(not_equal_edge_p): ... this; reverse semantics.
(remove_predictions_associated_with_edge): Fix.

Correct ChangeLog foul ups.

This patch fixes PR96312. Cures a used uninitialized warning.

2020-08-10 Paul Thomas <pault@gcc.gnu.org>

gcc/fortran
PR fortran/96312
* trans-expr.c (fcncall_realloc_result): Only compare shapes if
lhs was allocated..

gcc/testsuite/
PR fortran/96312
* gfortran.dg/pr96312.f90: New test.

This patch fixes PR96102. See the explanatory comment in the testcase.

2020-08-10 Paul Thomas <pault@gcc.gnu.org>

gcc/fortran
PR fortran/96102
* resolve.c (check_host_association): Replace the gcc_assert
with an error for internal procedures.

gcc/testsuite/
PR fortran/96102
* gfortran.dg/pr96102.f90: New test.

Using UNSPEC for vector compare to mask register.

For rtx like (eq:HI (V8SI 90) (V8SI 91)), cse will take it as a
boolean value and try to do some optimization. But it is not true for
vector compare, also other places in rtl passes hold the same
assumption.

2020-07-20 Hongtao Liu <hongtao.liu@intel.com>

gcc/
PR target/96243
* config/i386/i386-expand.c (ix86_expand_sse_cmp): Refine for
maskcmp.
(ix86_expand_mask_vec_cmp): Change prototype.
* config/i386/i386-protos.h (ix86_expand_mask_vec_cmp): Change prototype.
* config/i386/i386.c (ix86_print_operand): Remove operand
modifier 'I'.
* config/i386/sse.md
(*<avx512>_cmp<mode>3<mask_scalar_merge_name><round_saeonly_name>): Deleted.
(*<avx512>_cmp<mode>3<mask_scalar_merge_name>): Ditto.
(*<avx512>_ucmp<mode>3<mask_scalar_merge_name>): Ditto.
(*<avx512>_ucmp<mode>3<mask_scalar_merge_name>,
avx512f_maskcmp<mode>3): Ditto.

gcc/testsuite
* gcc.target/i386/pr92865-1.c: Adjust testcase.

Daily bump.

middle-end: Correct calculation of mul_widen_cost and mul_highpart_cost.

This patch fixes a subtle bug in the depths of GCC's synth_mult,
where the middle-end queries whether (how well) the target supports
widening and highpart multiplications by calling targetm.rtx_costs.
The code in init_expmed and init_expmed_one_mode iterates over various
RTL patterns querying the cost of each. To avoid generating & garbage
collecting too much junk, it reuses the same RTL over and over, but
adjusting the modes between each call.

Alas this reuse of state is a little fragile, and at some point a
change to init_expmed_one_conv has resulted in the state (mode of
a register) being changed, but not reset before being used again.

Using the old software engineering/defensive programming maxim of
"why fix a bug just once, if it can be fixed in multiple places",
this patch both restores the original value in init_expmed_one_conv,
and also sets it to the expected value in init_expmed_one_mode.
This should hopefully signal the need to be careful of invariants for
anyone modifying this code in future.

2020-08-09 Roger Sayle <roger@nextmovesoftware.com>

gcc/ChangeLog
* expmed.c (init_expmed_one_conv): Restore all->reg's mode.
(init_expmed_one_mode): Set all->reg to desired mode.

gcc/testsuite/ChangeLog
PR target/71321
* gcc.target/i386/pr71321.c: Check that the code doesn't use
the 4B zero displacement lea, not that it uses lea.

testsuite, Darwin: XFAIL runs for two timode conversion tests.

X86 Darwin fails these at present, because (to work around PR80556)
we insert libSystem ahead of libgcc. The libSystem implementation
has a similar bug to one that was fixed for GCC. We need to fix
80556 properly, and then this issue will go away - we will be able
to use the libgcc impl as intended.

XFAIL the run for now, to reduce testsuite noise.

gcc/testsuite/ChangeLog:

* gcc.dg/torture/fp-int-convert-timode-3.c: XFAIL run.
* gcc.dg/torture/fp-int-convert-timode-4.c: Likewise.

gcc.dg/pr44194-1.c: Skip for mmix.

The test makes sense only for targets that return the
"struct { int a, b, c; }" in registers (not in memory).

Starting a skip-construct is IMHO better than another iteration of
that obscuring "{ ... && { ! mytarget-*-* } }". New targets can just
append to the list without additional {}:s. I chose not to "convert"
any of the previous exclusions, as without targets to test, I'd surely
mess up {}-pairs.

A new effective_target would be even better, but such a
check_effective_target_returns_struct_in_memory (or complementary,
_in_registers) would surely have to be parametrized on the size and
type of the returned blob.

Maybe best to restrict to just x86_64, as seems to have been the
original problem target.

gcc/testsuite:
* gcc.dg/pr44194-1.c: Skip for mmix.

Daily bump.

gcc.dg/pr30957-1.c: xfail for mmix.

IV (loop2_unroll) doesn't like the mmix port.  The feelings are mutual.

For mmix, gcc.dg/pr30957-1.c fails (runtime and rtl-scan) for these
reasons:

- IV doesn't handle the zero-extension-by-shift sequences generated by
  middle-end (expr.c:convert_mode_scalar) in the absence of
  zero-extend patterns in a port.

- (when adding such patterns)
  IV doesn't understand the subreg constructs generated by middle-end
  in the absence of addsi3 and compare/branch in SImode (int).

- (when hacking pr30957-1.c to iterate using a register-mode type)
  IV doesn't understand the admittedly weird SFmode operations
  (performing in DFmode, then truncating, for lack of SFmode
  operations, but presence of truncdfsf2 and float_extendsfdf2) in
  order to perform the "Expanding Accumulator" optimization.  When
  also editing the type in the test to be double instead of float, the
  test passes.

While at least the last point seems like a valid reason to just skip
the test for mmix, it also seems possible that IV (and maybe
convert_mode_scalar by e.g. adding REG_EQUIV notes) be improved to be
both smarter and dumber to actually make the test pass, so I think
it's better to use xfail.  Smarter: understanding zero-extend-
by-shift and subregged operations better, and "seeing" the
accumulation through the DF/SFmode truncations and expansions.
Dumber: ignoring the cost; unrolling the several operations per SFmode
add anyway.

I'm considering adding a variant of this test with "double" and
"__SIZE_TYPE__" iteration types, as that passes for mmix as-is.
Maybe as a mmix-specific test; the world has suffered enough from the
questionable gcc.dg/pr30957-1.c (see the test and its history).

gcc/testsuite:
* gcc.dg/pr30957-1.c: xfail for mmix.

rs6000: MMA built-ins reject typedefs of MMA types

We do not allow conversions between the MMA types and other types.
However, we are being too strict in not matching MMA types with
typdefs of those types.  Use TYPE_CANONICAL to see through the
types to their canonical types before comparing them.

2020-08-08  Peter Bergner  <bergner@linux.ibm.com>

gcc/
PR target/96530
* config/rs6000/rs6000.c (rs6000_invalid_conversion): Use canonical
types for type comparisons.  Refactor code to simplify it.

gcc/testsuite/
PR target/96530
* gcc.target/powerpc/pr96530.c: New test.

openmp: Handle clauses with gimple sequences in convert_nonlocal_omp_clauses properly

If the walk_body on the various sequences of reduction, lastprivate and/or linear
clauses needs to create a temporary variable, we should declare that variable
in that sequence rather than outside, where it would need to be privatized inside of
the construct.

2020-08-08 Jakub Jelinek <jakub@redhat.com>

PR fortran/93553
* tree-nested.c (convert_nonlocal_omp_clauses): For
OMP_CLAUSE_REDUCTION, OMP_CLAUSE_LASTPRIVATE and OMP_CLAUSE_LINEAR
save info->new_local_var_chain around walks of the clause gimple
sequences and declare_vars if needed into the sequence.

2020-08-08 Tobias Burnus <tobias@codesourcery.com>

PR fortran/93553
* testsuite/libgomp.fortran/pr93553.f90: New test.

openmp: Avoid floating point comparison at the end of bb with -fnon-call-exceptions

The following testcase ICEs with -fexceptions -fnon-call-exceptions because
in that mode floating point comparisons should not be done at the end of bb
in GIMPLE_COND. Fixed by forcing it into a bool SSA_NAME and comparing that against
false.

2020-08-08 Jakub Jelinek <jakub@redhat.com>

PR tree-optimization/96424
* omp-expand.c: Include tree-eh.h.
(expand_omp_for_init_vars): Handle -fexceptions -fnon-call-exceptions
by forcing floating point comparison into a bool temporary.

* c-c++-common/gomp/pr96424.c: New test.

libgo: update to Go1.15rc2 release

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/247517

Daily bump.

libstdc++: Fix ambiguous comparisons in __gnu_debug::bitset [PR 96303]

With -pedantic the debug mode bitset has an ambiguous equality
comparison operator, because it tries to compare the non-debug base to
the debug object. The base object can be converted to another debug
bitset, making the same operator== a candidate again.

The fix is to do the comparison on both base objects, so the operator
for the derived type isn't a candidate.

For the inequality operator the same change should be done, but that
operator can be removed entirely for C++20 because it can be synthesized
by the compiler.

I don't think either equality or inequality operators are really needed,
because the public _GLIBCXX_STD_C::bitset base class cam always be
compared using its own comparison operators. I'm not changing that here
though.

libstdc++-v3/ChangeLog:

PR libstdc++/96303
* include/debug/bitset (bitset::operator==): Call _M_base() on
right operand.
(bitset::operator!=): Likewise, but don't define it at all when
default comparisons are supported by the compiler.
* testsuite/23_containers/bitset/operations/96303.cc: New test.

Disable some VEC_COND_EXPR transformations after vector lowering

ARM understands VEC_COND_EXPR<v == w, -1, 0> but not a plain v == w which is
fed to something other than VEC_COND_EXPR (say BIT_IOR_EXPR). This patch avoids
introducing the second kind of statement after the vector lowering pass, which
is the last chance to turn v == w back into something the target handles.

This is just a workaround to avoid ICEs, a v == w produced before vector
lowering will yield pretty bad code. Either the arm target needs to learn to
handle vector comparisons (aarch64 already does), or the middle-end needs to
fall back to vcond when plain comparisons are not supported (or ...).

2020-08-07 Marc Glisse <marc.glisse@inria.fr>

* generic-match-head.c (optimize_vectors_before_lowering_p): New
function.
* gimple-match-head.c (optimize_vectors_before_lowering_p):
Likewise.
* match.pd ((v ? w : 0) ? a : b, c1 ? c2 ? a : b : b): Use it.

libstdc++: Replace some VERIFY tests with static_assert

libstdc++-v3/ChangeLog:

* testsuite/18_support/comparisons/algorithms/partial_order.cc:
Replace VERIFY with static_assert where the compiler now
allows it.
* testsuite/18_support/comparisons/algorithms/weak_order.cc:
Likewise.

libstdc++: Fix linker script patterns for 32-bit targets

When making the patterns less greedy I forgot to use [jmy] for unsigned
integer parameters.

libstdc++-v3/ChangeLog:

* config/abi/pre/gnu.ver: Fix wildcards for wstring symbols.

tree-optimization/96514 - avoid if-converting control-altering calls

This avoids if-converting when encountering control-altering calls.

2020-08-07 Richard Biener <rguenther@suse.de>

PR tree-optimization/96514
* tree-if-conv.c (if_convertible_bb_p): If the last stmt
is a call that is control-altering, fail.

* gcc.dg/pr96514.c: New testcase.

bpf: remove trailing whitespaces from source files

This patch is a little cleanup that removes trailing whitespaces from
the bpf backend source files.

2020-08-07 Jose E. Marchesi <jose.marchesi@oracle.com>

gcc/
* config/bpf/bpf.md: Remove trailing whitespaces.
* config/bpf/constraints.md: Likewise.
* config/bpf/predicates.md: Likewise.

gcc/testsuite/
* gcc.target/bpf/diag-funargs-2.c: Remove trailing whitespaces.
* gcc.target/bpf/skb-ancestor-cgroup-id.c: Likewise.
* gcc.target/bpf/helper-xdp-adjust-meta.c: Likewise.
* gcc.target/bpf/helper-xdp-adjust-head.c: Likewise.
* gcc.target/bpf/helper-tcp-check-syncookie.c: Likewise.
* gcc.target/bpf/helper-sock-ops-cb-flags-set.c
* gcc.target/bpf/helper-sysctl-set-new-value.c: Likewise.
* gcc.target/bpf/helper-sysctl-get-new-value.c: Likewise.
* gcc.target/bpf/helper-sysctl-get-name.c: Likewise.
* gcc.target/bpf/helper-sysctl-get-current-value.c: Likewise.
* gcc.target/bpf/helper-strtoul.c: Likewise.
* gcc.target/bpf/helper-strtol.c: Likewise.
* gcc.target/bpf/helper-sock-map-update.c: Likewise.
* gcc.target/bpf/helper-sk-storage-get.c: Likewise.
* gcc.target/bpf/helper-sk-storage-delete.c: Likewise.
* gcc.target/bpf/helper-sk-select-reuseport.c: Likewise.
* gcc.target/bpf/helper-sk-release.c: Likewise.
* gcc.target/bpf/helper-sk-redirect-map.c: Likewise.
* gcc.target/bpf/helper-sk-lookup-upd.c: Likewise.
* gcc.target/bpf/helper-sk-lookup-tcp.c: Likewise.
* gcc.target/bpf/helper-skb-change-head.c: Likewise.
* gcc.target/bpf/helper-skb-cgroup-id.c: Likewise.
* gcc.target/bpf/helper-skb-adjust-room.c: Likewise.
* gcc.target/bpf/helper-set-hash.c: Likewise.
* gcc.target/bpf/helper-setsockopt.c: Likewise.
* gcc.target/bpf/helper-redirect-map.c: Likewise.
* gcc.target/bpf/helper-rc-repeat.c: Likewise.
* gcc.target/bpf/helper-rc-keydown.c: Likewise.
* gcc.target/bpf/helper-probe-read-str.c: Likewise.
* gcc.target/bpf/helper-perf-prog-read-value.c: Likewise.
* gcc.target/bpf/helper-perf-event-read-value.c: Likewise.
* gcc.target/bpf/helper-override-return.c: Likewise.
* gcc.target/bpf/helper-msg-redirect-map.c: Likewise.
* gcc.target/bpf/helper-msg-pull-data.c: Likewise.
* gcc.target/bpf/helper-msg-cork-bytes.c: Likewise.
* gcc.target/bpf/helper-msg-apply-bytes.c: Likewise.
* gcc.target/bpf/helper-lwt-seg6-store-bytes.c: Likewise.
* gcc.target/bpf/helper-lwt-seg6-adjust-srh.c: Likewise.
* gcc.target/bpf/helper-lwt-seg6-action.c: Likewise.
* gcc.target/bpf/helper-lwt-push-encap.c: Likewise.
* gcc.target/bpf/helper-get-socket-uid.c: Likewise.
* gcc.target/bpf/helper-get-socket-cookie.c: Likewise.
* gcc.target/bpf/helper-get-local-storage.c: Likewise.
* gcc.target/bpf/helper-get-current-cgroup-id.c: Likewise.
* gcc.target/bpf/helper-getsockopt.c: Likewise.
* gcc.target/bpf/diag-funargs-3.c: Likewise.

[testsuite] Add gcc.dg/ia64-sync-5.c

There currently is no sync_char_short-enabled run test that tests
__sync_val_compare_and_swap.

Fix this by copying ia64-sync-3.c and modifying it for char/short.

Tested on x86_64.

2020-08-06 Kwok Cheung Yeung <kcy@codesourcery.com>
Tom de Vries <tdevries@suse.de>

gcc/testsuite/ChangeLog:

* gcc.dg/ia64-sync-5.c: New test.

Power10: Add BRD, BRW, and BRH support.

This patch adds support for the ISA 3.1 (power10) instructions that does a byte
swap of values in GPR registers.

gcc/
2020-08-07  Michael Meissner  <meissner@linux.ibm.com>

* config/rs6000/rs6000.md (bswaphi2_reg): Add ISA 3.1 support.
(bswapsi2_reg): Add ISA 3.1 support.
(bswapdi2): Rename bswapdi2_xxbrd to bswapdi2_brd.
(bswapdi2_brd,bswapdi2_xxbrd): Rename.  Add ISA 3.1 support.

gcc/testsuite/
2020-08-07  Michael Meissner  <meissner@linux.ibm.com>

* gcc.target/powerpc/bswap-brd.c: New test.
* gcc.target/powerpc/bswap-brw.c: New test.
* gcc.target/powerpc/bswap-brh.c: New test.

PR96493, powerpc local call linkage failure

This corrects current_file_function_operand, an operand predicate used
to determine whether a symbol_ref is safe to use with the local_call
patterns.  Calls between pcrel and non-pcrel code need to go via
linker stubs.  In the case of non-pcrel code to pcrel the stub saves
r2 but there needs to be a nop after the branch for the r2 restore.
So the local_call patterns can't be used there.  For pcrel code to
non-pcrel the local_call patterns could still be used, but I thought
it better to not use them since the call isn't direct.  Code generated
by the corresponding call_nonlocal_aix for pcrel is identical anyway.

Incidentally, without the TREE_CODE () == FUNCTION_DECL test,
gcc.c-torture/compile/pr37433.c and pr37433-1.c ICE.  Also, if you
make the test more strict by disallowing an op without a
SYMBOL_REF_DECL then a bunch of go and split-stack tests fail.  That's
because a prologue call to __morestack can't have a following nop.
(__morestack calls its caller at a fixed offset from the __morestack
call!)

gcc/
PR target/96493
* config/rs6000/predicates.md (current_file_function_operand): Don't
accept functions that differ in r2 usage.

gcc/testsuite/
* gcc.target/powerpc/pr96493.c: New file.

Daily bump.

mmix: fix gcc.dg/loop-9.c by more accurate move insns

It looks like gcc.dg/loop-9.c kind-of works as sentinel for sane
move-instruction generation for a port.

Looking at the
FAIL: gcc.dg/loop-9.c scan-rtl-dump loop2_invariant "Decided"
FAIL: gcc.dg/loop-9.c scan-rtl-dump loop2_invariant "without introducing a new temporary register"
it seems the problem is that in the loop:

  for (i = 0; i < 100; i++)
    a[i] = 18.4242;

the move insn corresponding to "a[i] = 18.4242" happens to be
generated as a move of a constant to a memory address, using no
registers except for the address (edited):

(insn 9 8 10 3 (set (mem:DF (reg:DI 269 [ ivtmp::9 ]))
        (const_double:DF 1.84241999e+1)) "x/loop-9.c":9:10 6 {movdf})

To wit, at the loop2 pass there's no register-initialization to move
out of the loop!  The insn above isn't accurate and has to be fixed up
at register allocation time to make constraints match.  While there
are insns to set memory to constant in MMIX, that's limited to 64-bit
moves corresponding to the integer bit-patterns for 0..255, and
18.4242 isn't one of them.  (Only 0.0 matches; the bit-patterns for
0..255 would IIUC be interpreted as denormal floating-point numbers
a.k.a. subnormal numbers and don't seem worthwhile to handle.)

The fault is with the port, for not requiring a register for an
operand that actually requires an intermediate register, in order to
enable pre-register-allocation passes to do their job.  The movdf
pattern (actually, all MMIX movM), only required the destination to be
a non-immediate operand and the source to be a general_operand,
i.e. anything-to-anything.

Better force the source to be a register, when asked to generate such
a move insn.  Also, make operands stay sane by using the matching insn
condition to require one of the operands to be a register
pre-register-allocation (for sake of combine-like passes that cook up
"simplified" insns, possibly losing the use of a register).  Looking
no deeper than at the results of test-runs with different variants, I
see that the latter "safety latch" has no effect on the test-results
(at 919c9d4bd3db7da0), but it just feels like the right thing to do.
Similarly, there's no effect on test-suite results, to do the same not
just for movdf but for all moves.

gcc:
* config/mmix/mmix.md (MM): New mode_iterator.
("mov<mode>"): New expander to expand for all MM-modes.
("*movqi_expanded", "*movhi_expanded", "*movsi_expanded")
("*movsf_expanded", "*movdf_expanded"): Rename from the
corresponding mov<M> named pattern.  Add to the condition that
either operand must be a register_operand.
("*movdi_expanded"): Similar, but also allow STCO in the condition.

libstdc++: Implement P0966 std::string::reserve should not shrink

Remove ability for reserve(n) to reduce a string's capacity. Add a new
reserve() overload that makes a shrink-to-fit request, and make
shrink_to_fit() use that.

libstdc++-v3/ChangeLog:

2020-07-30 Andrew Luo <andrewluotechnologies@outlook.com>
Jonathan Wakely <jwakely@redhat.com>

* config/abi/pre/gnu.ver (GLIBCXX_3.4): Use less greedy
patterns for basic_string members.
(GLIBCXX_3.4.29): Export new basic_string::reserve symbols.
* doc/xml/manual/status_cxx2020.xml: Update P0966 status.
* include/bits/basic_string.h (shrink_to_fit()): Call reserve().
(reserve(size_type)): Remove default argument.
(reserve()): Declare new overload.
[!_GLIBCXX_USE_CXX11_ABI] (shrink_to_fit, reserve): Likewise.
* include/bits/basic_string.tcc (reserve(size_type)): Remove
support for shrinking capacity.
(reserve()): Perform shrink-to-fit operation.
[!_GLIBCXX_USE_CXX11_ABI] (reserve): Likewise.
* testsuite/21_strings/basic_string/capacity/1.cc: Adjust to
reflect new behavior.
* testsuite/21_strings/basic_string/capacity/char/1.cc:
Likewise.
* testsuite/21_strings/basic_string/capacity/char/18654.cc:
Likewise.
* testsuite/21_strings/basic_string/capacity/char/2.cc:
Likewise.
* testsuite/21_strings/basic_string/capacity/wchar_t/1.cc:
Likewise.
* testsuite/21_strings/basic_string/capacity/wchar_t/18654.cc:
Likewise.
* testsuite/21_strings/basic_string/capacity/wchar_t/2.cc:
Likewise.

libstdc++: Do not set eofbit eagerly in operator>>(istream&, char(&)[N])

Similar to the bugs I fixed recently in istream::ignore, we incorrectly
set eofbit too often in operator>>(istream&, string&) and
operator>>(istream&. char(&)[N]).

We should only set eofbit if we reach EOF but would have kept going
otherwise. If we've already extracted the maximum number of characters
(whether that's because of the buffer size or the istream's width())
then we should not set eofbit.

libstdc++-v3/ChangeLog:

* include/bits/basic_string.tcc
(operator>>(basic_istream&, basic_string&)): Do not set eofbit
if extraction stopped after in.width() characters.
* src/c++98/istream-string.cc (operator>>(istream&, string&)):
Likewise.
* include/bits/istream.tcc (__istream_extract): Do not set
eofbit if extraction stopped after n-1 characters.
* src/c++98/istream.cc (__istream_extract): Likewise.
* testsuite/21_strings/basic_string/inserters_extractors/char/13.cc: New test.
* testsuite/21_strings/basic_string/inserters_extractors/wchar_t/13.cc: New test.
* testsuite/27_io/basic_istream/extractors_character/char/5.cc: New test.
* testsuite/27_io/basic_istream/extractors_character/wchar_t/5.cc: New test.

arm: Clear canary value after stack_protect_test [PR96191]

The stack_protect_test patterns were leaving the canary value in the
temporary register, meaning that it was often still in registers on
return from the function. An attacker might therefore have been
able to use it to defeat stack-smash protection for a later function.

gcc/
PR target/96191
* config/arm/arm.md (arm_stack_protect_test_insn): Zero out
operand 2 after use.
* config/arm/thumb1.md (thumb1_stack_protect_test_insn): Likewise.

gcc/testsuite/
* gcc.target/arm/stack-protector-1.c: New test.
* gcc.target/arm/stack-protector-2.c: Likewise.

libstdc++: Fix unnecessary allocations in read_symlink [PR 96484]

libstdc++-v3/ChangeLog:

PR libstdc++/96484
* src/c++17/fs_ops.cc (fs::read_symlink): Return an error
immediately for non-symlinks.
* src/filesystem/ops.cc (fs::read_symlink): Likewise.

libstdc++: Adjust overflow prevention to operator>>

This adjusts the overflow prevention added to operator>> so that we can
distinguish "unknown size" from "zero size", and avoid writing anything
at all in to zero sized buffers.

This also removes the incorrect comment saying extraction stops at a
null byte.

libstdc++-v3/ChangeLog:

* include/std/istream (operator>>(istream&, char*)): Add
attributes to get warnings for pointers that are null or known
to point to the end of a buffer. Request upper bound from
__builtin_object_size check and handle zero-sized buffer case.
(operator>>(istream&, signed char))
(operator>>(istream&, unsigned char*)): Add attributes.
* testsuite/27_io/basic_istream/extractors_character/char/overflow.cc:
Check extracting into the middle of a buffer.
* testsuite/27_io/basic_istream/extractors_character/wchar_t/overflow.cc: New test.

rs6000: Don't ICE when spilling an MMA accumulator

When we spill an accumulator that has a known zero value, LRA will emit
a new (set (reg:PXI ...) 0) insn, but it does not use the mma_xxsetaccz
pattern to do it, leading to an unrecognized insn ICE.  The solution here
is to move the xxsetaccz instruction into the movpxi pattern and have the
xxsetaccz pattern call the move pattern.

2020-08-06  Peter Bergner  <bergner@linux.ibm.com>

gcc/
PR target/96446
* config/rs6000/mma.md (*movpxi): Add xxsetaccz generation.
Disable split for zero constant source operand.
(mma_xxsetaccz): Change to define_expand.  Call gen_movpxi.

gcc/testsuite/
PR target/96446
* gcc.target/powerpc/pr96446.c: New test.

x86: Restrict new gcc.target/i386/minmax-9.c test to !ia32.

As reported by Jakub Jelinek, this test fails with -m32.
Sorry for any inconvenience.

2020-08-06 Roger Sayle <roger@nextmovesoftware.com>

gcc/testsuite/ChangeLog
* gcc.target/i386/minmax-9.c: Restrict test to !ia32.

reassoc: Improve maybe_optimize_range_tests [PR96480]

On the following testcase, if the IL before reassoc would be:
...
  <bb 4> [local count: 354334800]:
  if (x_3(D) == 2)
    goto <bb 7>; [34.00%]
  else
    goto <bb 5>; [66.00%]

  <bb 5> [local count: 233860967]:
  if (x_3(D) == 3)
    goto <bb 7>; [34.00%]
  else
    goto <bb 6>; [66.00%]

  <bb 6> [local count: 79512730]:

  <bb 7> [local count: 1073741824]:
  # prephitmp_7 = PHI <1(3), 1(4), 1(5), 1(2), 0(6)>
then we'd optimize it properly, but as bb 5-7 is instead:
  <bb 5> [local count: 233860967]:
  if (x_3(D) == 3)
    goto <bb 6>; [34.00%]
  else
    goto <bb 7>; [66.00%]

  <bb 6> [local count: 79512730]:

  <bb 7> [local count: 1073741824]:
  # prephitmp_7 = PHI <1(3), 1(4), 0(5), 1(2), 1(6)>
(i.e. the true/false edges on the last bb with condition swapped
and ditto for the phi args), we don't recognize it.  If bb 6
is empty, there should be no functional difference between the two IL
representations.

This patch handles those special cases.

2020-08-06  Jakub Jelinek  <jakub@redhat.com>

PR tree-optimization/96480
* tree-ssa-reassoc.c (suitable_cond_bb): Add TEST_SWAPPED_P argument.
If TEST_BB ends in cond and has one edge to *OTHER_BB and another
through an empty bb to that block too, if PHI args don't match, retry
them through the other path from TEST_BB.
(maybe_optimize_range_tests): Adjust callers.  Handle such LAST_BB
through inversion of the condition.

* gcc.dg/tree-ssa/pr96480.c: New test.

bpf: more flexible support for kernel helpers

This patch changes the existing support for BPF kernel helpers to be
more flexible, in two main ways.

First, there is no longer a hardcoded list of kernel helpers defined
in the compiler internals.  This is replaced by a new target-specific
attribute `kernel_helper' that the user can use to define her own
helpers, annotating function prototypes.

Second, following feedback from the kernel hackers, the pre-defined
helpers in the distributed bpf-helpers.h are no longer available
conditionally depending on the kernel version used in -mkernel.  The
command-line option stays for now, as it may be useful for other
things.

Target tests and documentation updated.

2020-08-06  Jose E. Marchesi  <jose.marchesi@oracle.com>

gcc/
* config/bpf/bpf-helpers.h (KERNEL_HELPER): Define.
(KERNEL_VERSION): Remove.
* config/bpf/bpf-helpers.def: Delete.
* config/bpf/bpf.c (bpf_handle_fndecl_attribute): New function.
(bpf_attribute_table): Define.
(bpf_helper_names): Delete.
(bpf_helper_code): Likewise.
(enum bpf_builtins): Adjust to new helpers mechanism.
(bpf_output_call): Likewise.
(bpf_init_builtins): Likewise.
(bpf_init_builtins): Likewise.
* doc/extend.texi (BPF Function Attributes): New section.
(BPF Kernel Helpers): Delete section.

gcc/testsuite/
* gcc.target/bpf/helper-bind.c: Adjust to new kernel helpers
mechanism.
* gcc.target/bpf/helper-bpf-redirect.c: Likewise.
* gcc.target/bpf/helper-clone-redirect.c: Likewise.
* gcc.target/bpf/helper-csum-diff.c: Likewise.
* gcc.target/bpf/helper-csum-update.c: Likewise.
* gcc.target/bpf/helper-current-task-under-cgroup.c: Likewise.
* gcc.target/bpf/helper-fib-lookup.c: Likewise.
* gcc.target/bpf/helper-get-cgroup-classid.c: Likewise.
* gcc.target/bpf/helper-get-current-cgroup-id.c: Likewise.
* gcc.target/bpf/helper-get-current-comm.c: Likewise.
* gcc.target/bpf/helper-get-current-pid-tgid.c: Likewise.
* gcc.target/bpf/helper-get-current-task.c: Likewise.
* gcc.target/bpf/helper-get-current-uid-gid.c: Likewise.
* gcc.target/bpf/helper-get-hash-recalc.c: Likewise.
* gcc.target/bpf/helper-get-listener-sock.c: Likewise.
* gcc.target/bpf/helper-get-local-storage.c: Likewise.
* gcc.target/bpf/helper-get-numa-node-id.c: Likewise.
* gcc.target/bpf/helper-get-prandom-u32.c: Likewise.
* gcc.target/bpf/helper-get-route-realm.c: Likewise.
* gcc.target/bpf/helper-get-smp-processor-id.c: Likewise.
* gcc.target/bpf/helper-get-socket-cookie.c: Likewise.
* gcc.target/bpf/helper-get-socket-uid.c: Likewise.
* gcc.target/bpf/helper-get-stack.c: Likewise.
* gcc.target/bpf/helper-get-stackid.c: Likewise.
* gcc.target/bpf/helper-getsockopt.c: Likewise.
* gcc.target/bpf/helper-ktime-get-ns.c: Likewise.
* gcc.target/bpf/helper-l3-csum-replace.c: Likewise.
* gcc.target/bpf/helper-l4-csum-replace.c: Likewise.
* gcc.target/bpf/helper-lwt-push-encap.c: Likewise.
* gcc.target/bpf/helper-lwt-seg6-action.c: Likewise.
* gcc.target/bpf/helper-lwt-seg6-adjust-srh.c: Likewise.
* gcc.target/bpf/helper-lwt-seg6-store-bytes.c: Likewise.
* gcc.target/bpf/helper-map-delete-elem.c: Likewise.
* gcc.target/bpf/helper-map-lookup-elem.c: Likewise.
* gcc.target/bpf/helper-map-peek-elem.c: Likewise.
* gcc.target/bpf/helper-map-pop-elem.c: Likewise.
* gcc.target/bpf/helper-map-push-elem.c: Likewise.
* gcc.target/bpf/helper-map-update-elem.c: Likewise.
* gcc.target/bpf/helper-msg-apply-bytes.c: Likewise.
* gcc.target/bpf/helper-msg-cork-bytes.c: Likewise.
* gcc.target/bpf/helper-msg-pop-data.c: Likewise.
* gcc.target/bpf/helper-msg-pull-data.c: Likewise.
* gcc.target/bpf/helper-msg-push-data.c: Likewise.
* gcc.target/bpf/helper-msg-redirect-hash.c: Likewise.
* gcc.target/bpf/helper-msg-redirect-map.c: Likewise.
* gcc.target/bpf/helper-override-return.c: Likewise.
* gcc.target/bpf/helper-perf-event-output.c: Likewise.
* gcc.target/bpf/helper-perf-event-read-value.c: Likewise.
* gcc.target/bpf/helper-perf-event-read.c: Likewise.
* gcc.target/bpf/helper-perf-prog-read-value.c: Likewise.
* gcc.target/bpf/helper-probe-read-str.c: Likewise.
* gcc.target/bpf/helper-probe-read.c: Likewise.
* gcc.target/bpf/helper-probe-write-user.c: Likewise.
* gcc.target/bpf/helper-rc-keydown.c: Likewise.
* gcc.target/bpf/helper-rc-pointer-rel.c: Likewise.
* gcc.target/bpf/helper-rc-repeat.c: Likewise.
* gcc.target/bpf/helper-redirect-map.c: Likewise.
* gcc.target/bpf/helper-set-hash-invalid.c: Likewise.
* gcc.target/bpf/helper-set-hash.c: Likewise.
* gcc.target/bpf/helper-setsockopt.c: Likewise.
* gcc.target/bpf/helper-sk-fullsock.c: Likewise.
* gcc.target/bpf/helper-sk-lookup-tcp.c: Likewise.
* gcc.target/bpf/helper-sk-lookup-upd.c: Likewise.
* gcc.target/bpf/helper-sk-redirect-hash.c: Likewise.
* gcc.target/bpf/helper-sk-redirect-map.c: Likewise.
* gcc.target/bpf/helper-sk-release.c: Likewise.
* gcc.target/bpf/helper-sk-select-reuseport.c: Likewise.
* gcc.target/bpf/helper-sk-storage-delete.c: Likewise.
* gcc.target/bpf/helper-sk-storage-get.c: Likewise.
* gcc.target/bpf/helper-skb-adjust-room.c: Likewise.
* gcc.target/bpf/helper-skb-cgroup-id.c: Likewise.
* gcc.target/bpf/helper-skb-change-head.c: Likewise.
* gcc.target/bpf/helper-skb-change-proto.c: Likewise.
* gcc.target/bpf/helper-skb-change-tail.c: Likewise.
* gcc.target/bpf/helper-skb-change-type.c: Likewise.
* gcc.target/bpf/helper-skb-ecn-set-ce.c: Likewise.
* gcc.target/bpf/helper-skb-get-tunnel-key.c: Likewise.
* gcc.target/bpf/helper-skb-get-tunnel-opt.c: Likewise.
* gcc.target/bpf/helper-skb-get-xfrm-state.c: Likewise.
* gcc.target/bpf/helper-skb-load-bytes-relative.c: Likewise.
* gcc.target/bpf/helper-skb-load-bytes.c: Likewise.
* gcc.target/bpf/helper-skb-pull-data.c: Likewise.
* gcc.target/bpf/helper-skb-set-tunnel-key.c: Likewise.
* gcc.target/bpf/helper-skb-set-tunnel-opt.c: Likewise.
* gcc.target/bpf/helper-skb-store-bytes.c: Likewise.
* gcc.target/bpf/helper-skb-under-cgroup.c: Likewise.
* gcc.target/bpf/helper-skb-vlan-pop.c: Likewise.
* gcc.target/bpf/helper-skb-vlan-push.c: Likewise.
* gcc.target/bpf/helper-skc-lookup-tcp.c: Likewise.
* gcc.target/bpf/helper-sock-hash-update.c: Likewise.
* gcc.target/bpf/helper-sock-map-update.c: Likewise.
* gcc.target/bpf/helper-sock-ops-cb-flags-set.c: Likewise.
* gcc.target/bpf/helper-spin-lock.c: Likewise.
* gcc.target/bpf/helper-spin-unlock.c: Likewise.
* gcc.target/bpf/helper-strtol.c: Likewise.
* gcc.target/bpf/helper-strtoul.c: Likewise.
* gcc.target/bpf/helper-sysctl-get-current-value.c: Likewise.
* gcc.target/bpf/helper-sysctl-get-name.c: Likewise.
* gcc.target/bpf/helper-sysctl-get-new-value.c: Likewise.
* gcc.target/bpf/helper-sysctl-set-new-value.c: Likewise.
* gcc.target/bpf/helper-tail-call.c: Likewise.
* gcc.target/bpf/helper-tcp-check-syncookie.c: Likewise.
* gcc.target/bpf/helper-tcp-sock.c: Likewise.
* gcc.target/bpf/helper-trace-printk.c: Likewise.
* gcc.target/bpf/helper-xdp-adjust-head.c: Likewise.
* gcc.target/bpf/helper-xdp-adjust-meta.c: Likewise.
* gcc.target/bpf/helper-xdp-adjust-tail.c: Likewise.
* gcc.target/bpf/skb-ancestor-cgroup-id.c: Likewise.

tree-optimization/96491 - avoid store commoning across abnormal edges

This avoids store commoning across abnormal edges since that easily
can disrupt abnormal coalescing because it might create overlapping
lifetime of variables.

2020-08-06 Richard Biener <rguenther@suse.de>

PR tree-optimization/96491
* tree-ssa-sink.c (sink_common_stores_to_bb): Avoid
sinking across abnormal edges.

* gcc.dg/torture/pr96491.c: New testcase.

tree-optimization/96483 - fix ICE in PRE with POLY_INT_CST

This adds a missing case for PRE expression re-materialization.

2020-08-06 Richard Biener <rguenther@suse.de>

PR tree-optimization/96483
* tree-ssa-pre.c (create_component_ref_by_pieces_1): Handle
POLY_INT_CST.

Remove std::map use from graphite

This replaces the use of std::map with hash_map for mapping
ISL ids to SSA names.

2020-08-06 Richard Biener <rguenther@suse.de>

* graphite-isl-ast-to-gimple.c (ivs_params): Use hash_map instead
of std::map.
(ivs_params_clear): Adjust.
(gcc_expression_from_isl_ast_expr_id): Likewise.
(graphite_create_new_loop): Likewise.
(add_parameters_to_ivs_params): Likewise.

x86_64: Integer min/max improvements.

This patch tweaks the way that min and max are expanded, so that the
semantics of these operations are visible to the early RTL optimization
passes, until split into explicit comparison and conditional move
instructions. The good news is that i386.md already contains all of
the required logic (many thanks to Richard Biener and Uros Bizjak),
but this is currently only enabled to scalar-to-vector (STV) synthesis
of min/max instructions.  This change enables this functionality for
all TARGET_CMOVE architectures for SImode, HImode and DImode.

2020-08-06  Roger Sayle  <roger@nextmovesoftware.com>
    Uroš Bizjak  <ubizjak@gmail.com>

gcc/ChangeLog
* config/i386/i386.md (MAXMIN_IMODE): No longer needed.
(<maxmin><mode>3):  Support SWI248 and general_operand for
second operand, when TARGET_CMOVE.
(<maxmin><mode>3_1 splitter): Optimize comparisons against
0, 1 and -1 to use "test" instead of "cmp".
(*<maxmin>di3_doubleword): Likewise, allow general_operand
and enable on TARGET_CMOVE.
(peephole2): Convert clearing a register after a flag setting
instruction into an xor followed by the original flag setter.

gcc/testsuite/ChangeLog
* gcc.target/i386/minmax-8.c: New test.
* gcc.target/i386/minmax-9.c: New test.
* gcc.target/i386/minmax-10.c: New test.
* gcc.target/i386/minmax-11.c: New test.

ipa-fnsummary: Include <vector> the proper way

This fixes a bootstrap error with clang 10 that would complain
  /usr/include/c++/v1/typeinfo:346:5: error: no member named
  'fancy_abort' in namespace 'std::__1'; did you mean simply
  'fancy_abort'?
It mirrors how this is handled in gcov.c and indirectly includes
<vector> via system.h.

gcc/ChangeLog:

* ipa-fnsummary.c (INCLUDE_VECTOR): Define.
Remove direct inclusion of <vector>.

vect/rs6000: Support vector with length cost modeling

This patch is to add the cost modeling for vector with length,
it mainly follows what we generate for vector with length in
functions vect_set_loop_controls_directly and vect_gen_len
at the worst case.

For Power, the length is expected to be in bits 0-7 (high bits),
we have to model the cost of shifting bits, which is implemented
in adjust_vect_cost_per_loop.

Bootstrapped/regtested on powerpc64le-linux-gnu (P9) with explicit
param vect-partial-vector-usage=1.

gcc/ChangeLog:

* config/rs6000/rs6000.c (rs6000_adjust_vect_cost_per_loop): New
function.
(rs6000_finish_cost): Call rs6000_adjust_vect_cost_per_loop.
* tree-vect-loop.c (vect_estimate_min_profitable_iters): Add cost
modeling for vector with length.
(vect_rgroup_iv_might_wrap_p): New function, factored out from...
* tree-vect-loop-manip.c (vect_set_loop_controls_directly): ...this.
Update function comment.
* tree-vect-stmts.c (vect_gen_len): Update function comment.
* tree-vectorizer.h (vect_rgroup_iv_might_wrap_p): New declare.

vect: Skip epilogue loops for dbgcnt check [PR96451]

As the PR shows, commit r11-2453 exposed one issue that vectorizer
wants to vectorize the epilogue loop and leaves the if-cvt body there,
but later dbgcnt check disables it, the left scalar mask_store
statement causes ICE.

As Richard pointed out in that PR, the dbgcnt is to count original
scalar loops, so this fix is to make it skip the epilogue loops.

gcc/ChangeLog:

* tree-vectorizer.c (try_vectorize_loop_1): Skip the epilogue loops
for dbgcnt check.

Daily bump.

libstdc++: Break long lines to fit in 80 columns

libstdc++-v3/ChangeLog:

* include/std/atomic (atomic<T>::store): Reformat.

libstdc++: Change URL for PSTL again

libstdc++-v3/ChangeLog:

* doc/xml/manual/status_cxx2017.xml: Replace oneAPI DPC++ link
with LLVM repo for PSTL.
* doc/html/manual/status.html: Regenerate.

libstdc++: Replace operator>>(istream&, char*) [LWG 2499]

P0487R1 resolved LWG 2499 for C++20 by removing the operator>> overloads
that have high risk of buffer overflows. They were replaced by
equivalents that only accept a reference to an array, and so can
guarantee not to write past the end of the array.

In order to support both the old and new functionality, this patch
introduces a new overloaded __istream_extract function which takes a
maximum length. The new operator>> overloads use the array size as the
maximum length. The old overloads now use __builtin_object_size to
determine the available buffer size if available (which requires -O2) or
use numeric_limits<streamsize>::max()/sizeof(char_type) otherwise. This
is a change in behaviour, as the old overloads previously always used
numeric_limits<streamsize>::max(), without considering sizeof(char_type)
and without attempting to prevent overflows.

Because they now do little more than call __istream_extract, the old
operator>> overloads are very small inline functions. This means there
is no advantage to explicitly instantiating them in the library (in fact
that would prevent the __builtin_object_size checks from ever working).
As a result, the explicit instantiation declarations can be removed from
the header. The explicit instantiation definitions are still needed, for
backwards compatibility with existing code that expects to link to the
definitions in the library.

While working on this change I noticed that src/c++11/istream-inst.cc
has the following explicit instantiation definition:
template istream& operator>>(istream&, char*);
This had no effect (and so should not have been present in that file),
because there was an explicit specialization declared in <istream> and
defined in src/++98/istream.cc. However, this change removes the
explicit specialization, and now the explicit instantiation definition
is necessary to ensure the symbol gets defined in the library.

libstdc++-v3/ChangeLog:

* config/abi/pre/gnu.ver (GLIBCXX_3.4.29): Export new symbols.
* include/bits/istream.tcc (__istream_extract): New function
template implementing both of operator>>(istream&, char*) and
operator>>(istream&, char(&)[N]). Add explicit instantiation
declaration for it. Remove explicit instantiation declarations
for old function templates.
* include/std/istream (__istream_extract): Declare.
(operator>>(basic_istream<C,T>&, C*)): Define inline and simply
call __istream_extract.
(operator>>(basic_istream<char,T>&, signed char*)): Likewise.
(operator>>(basic_istream<char,T>&, unsigned char*)): Likewise.
(operator>>(basic_istream<C,T>&, C(7)[N])): Define for LWG 2499.
(operator>>(basic_istream<char,T>&, signed char(&)[N])):
Likewise.
(operator>>(basic_istream<char,T>&, unsigned char(&)[N])):
Likewise.
* include/std/streambuf (basic_streambuf): Declare char overload
of __istream_extract as a friend.
* src/c++11/istream-inst.cc: Add explicit instantiation
definition for wchar_t overload of __istream_extract. Remove
explicit instantiation definitions of old operator>> overloads
for versioned-namespace build.
* src/c++98/istream.cc (operator>>(istream&, char*)): Replace
with __istream_extract(istream&, char*, streamsize).
* testsuite/27_io/basic_istream/extractors_character/char/3.cc:
Do not use variable-length array.
* testsuite/27_io/basic_istream/extractors_character/char/4.cc:
Do not run test for C++20.
* testsuite/27_io/basic_istream/extractors_character/char/9555-ic.cc:
Do not test writing to pointers for C++20.
* testsuite/27_io/basic_istream/extractors_character/char/9826.cc:
Use array instead of pointer.
* testsuite/27_io/basic_istream/extractors_character/wchar_t/3.cc:
Do not use variable-length array.
* testsuite/27_io/basic_istream/extractors_character/wchar_t/4.cc:
Do not run test for C++20.
* testsuite/27_io/basic_istream/extractors_character/wchar_t/9555-ic.cc:
Do not test writing to pointers for C++20.
* testsuite/27_io/basic_istream/extractors_character/char/lwg2499.cc:
New test.
* testsuite/27_io/basic_istream/extractors_character/char/lwg2499_neg.cc:
New test.
* testsuite/27_io/basic_istream/extractors_character/char/overflow.cc:
New test.
* testsuite/27_io/basic_istream/extractors_character/wchar_t/lwg2499.cc:
New test.
* testsuite/27_io/basic_istream/extractors_character/wchar_t/lwg2499_neg.cc:
New test.

c++: cxx_eval_vec_init after zero-initialization [PR96282]

In the first testcase below, expand_aggr_init_1 sets up t's default
constructor such that the ctor first zero-initializes the entire base b,
followed by calling b's default constructor, the latter of which just
default-initializes the array member b::m via a VEC_INIT_EXPR.

So upon constexpr evaluation of this latter VEC_INIT_EXPR, ctx->ctor is
nonempty due to the prior zero-initialization, and we proceed in
cxx_eval_vec_init to append new constructor_elts to the end of ctx->ctor
without first checking if a matching constructor_elt already exists.
This leads to ctx->ctor having two matching constructor_elts for each
index.

This patch fixes this issue by truncating a zero-initialized array
CONSTRUCTOR in cxx_eval_vec_init_1 before we begin appending array
elements to it. We propagate its zeroed out state during evaluation by
clearing CONSTRUCTOR_NO_CLEARING on each new appended aggregate element.

gcc/cp/ChangeLog:

PR c++/96282
* constexpr.c (cxx_eval_vec_init_1): Truncate ctx->ctor and
then clear CONSTRUCTOR_NO_CLEARING on each appended element
initializer if we're initializing a previously zero-initialized
array object.

gcc/testsuite/ChangeLog:

PR c++/96282
* g++.dg/cpp0x/constexpr-array26.C: New test.
* g++.dg/cpp0x/constexpr-array27.C: New test.
* g++.dg/cpp2a/constexpr-init18.C: New test.

Co-authored-by: Jason Merrill <jason@redhat.com>

Added test case to make sure that legal cases still pass.

gcc/testsuite/ChangeLog:

PR fortran/96469
* gfortran.dg/do_check_14.f90: New test.

Static analysis for definition of DO index variables in contained procedures.

When encountering a procedure call in a DO loop, this patch checks if
the call is to a contained procedure, and if it is, check for
changes in the index variable.

gcc/fortran/ChangeLog:

PR fortran/96469
* frontend-passes.c (doloop_contained_function_call): New
function.
(doloop_contained_procedure_code): New function.
(CHECK_INQ): Macro for inquire checks.
(doloop_code): Invoke doloop_contained_procedure_code and
doloop_contained_function_call if appropriate.
(do_intent): Likewise.

gcc/testsuite/ChangeLog:

PR fortran/96469
* gfortran.dg/do_check_4.f90: Hide change in index variable
from compile-time analysis.
* gfortran.dg/do_check_13.f90: New test.

VEC_COND_EXPR optimizations

When vector comparisons were forced to use vec_cond_expr, we lost a number of optimizations (my fault for not adding enough testcases to
prevent that). This patch tries to unwrap vec_cond_expr a bit so some optimizations can still happen.

I wasn't planning to add all those transformations together, but adding one caused a regression, whose fix introduced a second regression,
etc.

Restricting to constant folding would not be sufficient, we also need at least things like X|0 or X&X. The transformations are quite
conservative with :s and folding only if everything simplifies, we may want to relax this later. And of course we are going to miss things
like a?b:c + a?c:b -> b+c.

In terms of number of operations, some transformations turning 2 VEC_COND_EXPR into VEC_COND_EXPR + BIT_IOR_EXPR + BIT_NOT_EXPR might not look
like a gain... I expect the bit_not disappears in most cases, and VEC_COND_EXPR looks more costly than a simpler BIT_IOR_EXPR.

2020-08-05 Marc Glisse <marc.glisse@inria.fr>

PR tree-optimization/95906
PR target/70314
* match.pd ((c ? a : b) op d, (c ? a : b) op (c ? d : e),
(v ? w : 0) ? a : b, c1 ? c2 ? a : b : b): New transformations.
(op (c ? a : b)): Update to match the new transformations.

* gcc.dg/tree-ssa/andnot-2.c: New file.
* gcc.dg/tree-ssa/pr95906.c: Likewise.
* gcc.target/i386/pr70314.c: Likewise.

aarch64: Clear canary value after stack_protect_test [PR96191]

The stack_protect_test patterns were leaving the canary value in the
temporary register, meaning that it was often still in registers on
return from the function.  An attacker might therefore have been
able to use it to defeat stack-smash protection for a later function.

gcc/
PR target/96191
* config/aarch64/aarch64.md (stack_protect_test_<mode>): Set the
CC register directly, instead of a GPR.  Replace the original GPR
destination with an extra scratch register.  Zero out operand 3
after use.
(stack_protect_test): Update accordingly.

gcc/testsuite/
PR target/96191
* gcc.target/aarch64/stack-protector-1.c: New test.
* gcc.target/aarch64/stack-protector-2.c: Likewise.