gcc/analyzer/ChangeLog:
PR analyzer/97029
* analyzer.cc (is_setjmp_call_p): Require the initial arg to be a
pointer.
* region-model.cc (region_model::deref_rvalue): Assert that the
svalue is of pointer type.
gcc/testsuite/ChangeLog:
* gcc.dg/analyzer/pr97029.c: New test.
When a thunk cannot be emitted in assembly directly, expand_thunk
generates regular GIMPLE code but unconditionally forces a tail
call to the target of the thunk. That's theoretically OK because
the thunk essentially forwards its parameters to the target, but
in practice the RTL expander can spill parameters passed by reference
on the stack in assign_parm_setup_reg.
gcc/ChangeLog:
* cgraphunit.c (cgraph_node::expand_thunk): Make sure to set
cfun->tail_call_marked when forcing a tail call.
* function.c (assign_parm_setup_reg): Always use a register to
load a parameter passed by reference if cfun->tail_call_marked.
gcc/testsuite/ChangeLog:
* gnat.dg/thunk1.adb: New test.
* gnat.dg/thunk1_pkg1.ads: New helper.
* gnat.dg/thunk1_pkg2.ads: Likewise.
* gnat.dg/thunk1_pkg2.adb: Likewise.
The following is mostly a mechanical change to rename the mffgpr/mftgpr
insn types to mtvsr/mfvsr to be more clear. It also removes Power6
references to those insn types since we no longer generate those
instructions.
2020-09-14 Pat Haugen <pthaugen@linux.ibm.com>
gcc/
* config/rs6000/power10.md (power10-mffgpr, power10-mftgpr): Rename to
power10-mtvsr/power10-mfvsr.
* config/rs6000/power6.md (X2F_power6, power6-mftgpr, power6-mffgpr):
Remove.
* config/rs6000/power8.md (power8-mffgpr, power8-mftgpr): Rename to
power8-mtvsr/power8-mfvsr.
* config/rs6000/power9.md (power9-mffgpr, power9-mftgpr): Rename to
power9-mtvsr/power9-mfvsr.
* config/rs6000/rs6000.c (rs6000_adjust_cost): Remove Power6
TYPE_MFFGPR cases.
* config/rs6000/rs6000.md (mffgpr, mftgpr, zero_extendsi<mode>2,
extendsi<mode>2, @signbit<mode>2_dm, lfiwax, lfiwzx, *movsi_internal1,
movsi_from_sf, *movdi_from_sf_zero_ext, *mov<mode>_internal,
movsd_hardfloat, movsf_from_si, *mov<mode>_hardfloat64, p8_mtvsrwz,
p8_mtvsrd_df, p8_mtvsrd_sf, p8_mfvsrd_3_<mode>, *movdi_internal64,
unpack<mode>_dm): Rename mffgpr/mftgpr to mtvsr/mfvsr.
* config/rs6000/vsx.md (vsx_mov<mode>_64bit, vsx_extract_<mode>,
vsx_extract_si, *vsx_extract_<mode>_p8): Likewise.
The following patch on top of the
https://gcc.gnu.org/pipermail/gcc-patches/2020-September/553801.html
patch fixes the gcc.target/arm/lto/pr96939_* test in certain ARM
configurations.
As said in the above mentioned patch, the generic code takes care of
saving/restoring TargetVariables or Target Save options, so this just
arranges for the generic code to save those instead of needing the
arm backend to do it manually.
2020-09-14 Jakub Jelinek <jakub@redhat.com>
* config/arm/arm.opt (x_arm_arch_string, x_arm_cpu_string,
x_arm_tune_string): Remove TargetSave entries.
(march=, mcpu=, mtune=): Add Save keyword.
* config/arm/arm.c (arm_option_save): Remove.
(TARGET_OPTION_SAVE): Don't redefine.
(arm_option_restore): Don't restore x_arm_*_string here.
> Seems a latent issue.
> Neither cl_optimization_{save,restore} nor cl_target_option_{save,restore}
> (nor any of the target hooks they call) saves or restores any opts_set
> values, so I think opts_set can be trusted only during option processing (if
> at all), but not later.
> So, short term a fix would be IMHO just stop using opts_set altogether in
> arm_configure_build_target, it doesn't make much sense to me, it should test
> if those strings are non-NULL instead, or at least do that when it is
> invoked from arm_option_restore (e.g. could be done by calling it with
> opts instead of &global_options_set ).
> Longer term, the question is if cl_optimization_{save,restore} and
> cl_target_option_{save,restore} shouldn't be changed not to only
> save/restore the options, but also save the opts_set flags.
> It could be done e.g. by adding a bool array or set of bool members
> to struct cl_optimization and struct cl_target_option , or even more compact
> by using bitmasks, pack each 64 adjacent option flags into a UHWI element
> of an array.
So, I've tried under debugger how it behaves and seems global_options_set
is really an or of whether an option has been ever seen as explicit, either
on the command line or in any of the option pragmas or optimize/target
attributes seen so far, so it isn't something that can be relied on.
The following patch implements the saving/restoring of the opts_set bits
(though only for the options/variables saved by the generic options-save.c
code, for the target specific stuff that isn't handled by the generic code
the opts_set argument is now passed to the hook and the backends can choose
e.g. to use a TargetSave variable to save the flags either individually or
together in some bitmask (or ignore it if they never need opts_set for the
options).
This patch itself doesn't fix the testcase failing on arm, but a follow up
patch will.
2020-09-14 Jakub Jelinek <jakub@redhat.com>
gcc/
* opt-read.awk: Also initialize extra_target_var_types array.
* opth-gen.awk: Emit explicit_mask arrays to struct cl_optimization
and cl_target_option. Adjust cl_optimization_save,
cl_optimization_restore, cl_target_option_save and
cl_target_option_restore declarations.
* optc-save-gen.awk: Add opts_set argument to cl_optimization_save,
cl_optimization_restore, cl_target_option_save and
cl_target_option_restore functions and save or restore opts_set
next to the opts values into or from explicit_mask arrays.
In cl_target_option_eq and cl_optimization_option_eq compare
explicit_mask arrays, in cl_target_option_hash and cl_optimization_hash
hash them and in cl_target_option_stream_out,
cl_target_option_stream_in, cl_optimization_stream_out and
cl_optimization_stream_in stream them.
* tree.h (build_optimization_node, build_target_option_node): Add
opts_set argument.
* tree.c (build_optimization_node): Add opts_set argument, pass it
to cl_optimization_save.
(build_target_option_node): Add opts_set argument, pass it to
cl_target_option_save.
* function.c (invoke_set_current_function_hook): Adjust
cl_optimization_restore caller.
* ipa-inline-transform.c (inline_call): Adjust cl_optimization_restore
and build_optimization_node callers.
* target.def (TARGET_OPTION_SAVE, TARGET_OPTION_RESTORE): Add opts_set
argument.
* target-globals.c (save_target_globals_default_opts): Adjust
cl_optimization_restore callers.
* toplev.c (process_options): Adjust build_optimization_node and
cl_optimization_restore callers.
(target_reinit): Adjust cl_optimization_restore caller.
* tree-streamer-in.c (lto_input_ts_function_decl_tree_pointers):
Adjust build_optimization_node and cl_optimization_restore callers.
* doc/tm.texi: Updated.
* config/aarch64/aarch64.c (aarch64_override_options): Adjust
build_target_option_node caller.
(aarch64_option_save, aarch64_option_restore): Add opts_set argument.
(aarch64_set_current_function): Adjust cl_target_option_restore
caller.
(aarch64_option_valid_attribute_p): Adjust cl_target_option_save,
cl_target_option_restore, cl_optimization_restore,
build_optimization_node and build_target_option_node callers.
* config/aarch64/aarch64-c.c (aarch64_pragma_target_parse): Adjust
cl_target_option_restore and build_target_option_node callers.
* config/arm/arm.c (arm_option_save, arm_option_restore): Add
opts_set argument.
(arm_option_override): Adjust cl_target_option_save,
build_optimization_node and build_target_option_node callers.
(arm_set_current_function): Adjust cl_target_option_restore caller.
(arm_valid_target_attribute_tree): Adjust build_target_option_node
caller.
(add_attribute): Formatting fix.
(arm_valid_target_attribute_p): Adjust cl_optimization_restore,
cl_target_option_restore, arm_valid_target_attribute_tree and
build_optimization_node callers.
* config/arm/arm-c.c (arm_pragma_target_parse): Adjust
cl_target_option_restore callers.
* config/csky/csky.c (csky_option_override): Adjust
build_target_option_node and cl_target_option_save callers.
* config/gcn/gcn.c (gcn_fixup_accel_lto_options): Adjust
build_optimization_node and cl_optimization_restore callers.
* config/i386/i386-builtins.c (get_builtin_code_for_version):
Adjust cl_target_option_save and cl_target_option_restore
callers.
* config/i386/i386-c.c (ix86_pragma_target_parse): Adjust
build_target_option_node and cl_target_option_restore callers.
* config/i386/i386-options.c (ix86_function_specific_save,
ix86_function_specific_restore): Add opts_set arguments.
(ix86_valid_target_attribute_tree): Adjust build_target_option_node
caller.
(ix86_valid_target_attribute_p): Adjust build_optimization_node,
cl_optimization_restore, cl_target_option_restore,
ix86_valid_target_attribute_tree and build_optimization_node callers.
(ix86_option_override_internal): Adjust build_target_option_node
caller.
(ix86_reset_previous_fndecl, ix86_set_current_function): Adjust
cl_target_option_restore callers.
* config/i386/i386-options.h (ix86_function_specific_save,
ix86_function_specific_restore): Add opts_set argument.
* config/nios2/nios2.c (nios2_option_override): Adjust
build_target_option_node caller.
(nios2_option_save, nios2_option_restore): Add opts_set argument.
(nios2_valid_target_attribute_tree): Adjust build_target_option_node
caller.
(nios2_valid_target_attribute_p): Adjust build_optimization_node,
cl_optimization_restore, cl_target_option_save and
cl_target_option_restore callers.
(nios2_set_current_function, nios2_pragma_target_parse): Adjust
cl_target_option_restore callers.
* config/pru/pru.c (pru_option_override): Adjust
build_target_option_node caller.
(pru_set_current_function): Adjust cl_target_option_restore
callers.
* config/rs6000/rs6000.c (rs6000_debug_reg_global): Adjust
cl_target_option_save caller.
(rs6000_option_override_internal): Adjust build_target_option_node
caller.
(rs6000_valid_attribute_p): Adjust build_optimization_node,
cl_optimization_restore, cl_target_option_save,
cl_target_option_restore and build_target_option_node callers.
(rs6000_pragma_target_parse): Adjust cl_target_option_restore and
build_target_option_node callers.
(rs6000_activate_target_options): Adjust cl_target_option_restore
callers.
(rs6000_function_specific_save, rs6000_function_specific_restore):
Add opts_set argument.
* config/s390/s390.c (s390_function_specific_restore): Likewise.
(s390_option_override_internal): Adjust s390_function_specific_restore
caller.
(s390_option_override, s390_valid_target_attribute_tree): Adjust
build_target_option_node caller.
(s390_valid_target_attribute_p): Adjust build_optimization_node,
cl_optimization_restore and cl_target_option_restore callers.
(s390_activate_target_options): Adjust cl_target_option_restore
caller.
* config/s390/s390-c.c (s390_cpu_cpp_builtins): Adjust
cl_target_option_save caller.
(s390_pragma_target_parse): Adjust build_target_option_node and
cl_target_option_restore callers.
gcc/c-family/
* c-attribs.c (handle_optimize_attribute): Adjust
cl_optimization_save, cl_optimization_restore and
build_optimization_node callers.
* c-pragma.c (handle_pragma_optimize): Adjust
build_optimization_node caller.
(handle_pragma_push_options): Adjust
build_optimization_node and build_target_option_node callers.
(handle_pragma_pop_options, handle_pragma_reset_options):
Adjust cl_optimization_restore callers.
gcc/go/
* go-gcc.cc (Gcc_backend::function): Adjust
cl_optimization_save, cl_optimization_restore and
build_optimization_node callers.
gcc/ada/
* gcc-interface/trans.c (gigi): Adjust build_optimization_node
caller.
As reported here
( https://gcc.gnu.org/pipermail/gcc-patches/2020-September/553070.html ),
when running test-case libgomp.c-c++-common/reduction-16.c for powerpc host
with nvptx accelerator, we run into:
...
unresolved symbol __sync_val_compare_and_swap_16
...
I can reproduce the problem on x86_64 with a trigger patch that:
- initializes ix86_isa_flags2 to TARGET_ISA2_CX16
- enables define_expand "atomic_load<mode>" in gcc/config/i386/sync.md
for TImode
The problem is that omp-expand.c generates atomic builtin calls based on
checks whether those are supported on the host, which forces the target to
support these, even though those checks fail for the accelerator target.
Fix this by:
- adding a __sync_val_compare_and_swap_16 in libgomp for nvptx,
which falls back onto libatomic's __atomic_compare_and_swap_16
- adding -foffload=-latomic in the test-case
Tested libgomp on x86_64-linux with nvptx accelerator.
Tested libgomp with trigger patch on x86_64-linux with nvptx accelerator.
libgomp/ChangeLog:
* config/nvptx/atomic.c: New file. Add
__sync_val_compare_and_swap_16.
* testsuite/libgomp.c-c++-common/reduction-16.c: Add -latomic for
target offload_target_nvptx.
2020-09-13 Roger Sayle <roger@nextmovesoftware.com>
gcc/ChangeLog
* config/pa/pa.c (hppa_rtx_costs) [ASHIFT, ASHIFTRT, LSHIFTRT]:
Provide accurate costs for DImode shifts of integer constants.
This enables warnings to be shown when a bad type is passed to va_arg
inside an extern(C) or extern(C++) function.
gcc/d/ChangeLog:
PR d/97002
* d-codegen.cc (d_build_call): Set input_location on CALL_EXPR.
* d-lang.cc: Include function.h.
(d_type_promotes_to): Do default conversions for C and C++ functions.
* intrinsics.cc (expand_intrinsic_vaarg): Use build1_loc to build
VA_ARG_EXPR.
gcc/testsuite/ChangeLog:
PR d/97002
* gdc.dg/pr97002.d: New test.
This is done so that the DWARF pass will emit a DW_TAG_typedef where the
member type of an enum can't be represented in an ENUMERAL_TYPE.
gcc/d/ChangeLog:
* d-builtins.cc (d_build_d_type_nodes): Call build_ctype() on all
basic front-end types.
* decl.cc (DeclVisitor::visit (EnumDeclaration *)): Always add decl to
current binding level.
(build_type_decl): Build TYPE_DECL as a typedef if not for an enum or
record type.
* types.cc (TypeVisitor::visit (TypeEnum *)): Set underlying type for
ENUMERAL_TYPEs. Build TYPE_DECL for non-numeric enums.
2020-09-12 Roger Sayle <roger@nextmovesoftware.com>
John David Anglin <danglin@gcc.gnu.org>
gcc/ChangeLog
* config/pa/pa.md (shrpsi4_1, shrpsi4_2): New define_insns split
out from previous shrpsi4 providing two commutitive variants using
plus_xor_ior_operator as a predicate.
(shrpdi4_1, shrpdi4_2, shrpdi_3, shrpdi_4): Likewise DImode versions
where _1 and _2 take register shifts, and _3 and _4 for integers.
(rotlsi3_internal): Name this anonymous instruction.
(rotrdi3): New DImode insn copied from rotrsi3.
(rotldi3): New DImode expander copied from rotlsi3.
(rotldi4_internal): New DImode insn copied from rotsi3_internal.
This is only the gigi part, in preparation for the bulk of the
implementation.
gcc/ada/ChangeLog:
* fe.h: Fix pilot error in previous change.
* gcc-interface/gigi.h (enum standard_datatypes): Add ADT_mulv128_decl.
(mulv128_decl): New macro.
(get_target_long_long_long_size): Declare.
* gcc-interface/decl.c (gnat_to_gnu_entity): Use a maximum size of
128 bits for discrete types if Enable_128bit_Types is true.
* gcc-interface/targtyps.c: Include target.h.
(get_target_long_long_long_size): New function.
* gcc-interface/trans.c (gigi): Initialize mulv128_decl if need be.
(build_binary_op_trapv): Call it for 128-bit multiplication.
* gcc-interface/utils.c (make_type_from_size): Enforce a maximum
size of 128 bits if Enable_128bit_Types is true.
This can result on the mainline in a segfault when an object declared
at library level is used in the declaration of another, local object.
gcc/ada/ChangeLog:
* gcc-interface/trans.c (lvalue_for_aggr_p) <N_Object_Declaration>:
Return false unconditionally.
This prevents the SLOC of the expression for a tag from being present
in the line debug info every time it is referenced for coverage purposes.
gcc/ada/ChangeLog:
* gcc-interface/trans.c (gnat_to_gnu) <N_Object_Declaration>: Clear
the SLOC of the expression of a tag.
This changes the compiler to accept again absolute address clause for
aliased array of unconstrained nominal subtype, instead of erroring
out in this case.
gcc/ada/ChangeLog:
* gcc-interface/decl.c (gnat_to_gnu_entity) <E_Variable>: Only give
a warning for the overlay of an aliased array with an unconstrained
nominal subtype if the address is absolute.
gcc/
2020-09-11 Michael Meissner <meissner@linux.ibm.com>
* config/rs6000/rs6000.c (rs6000_maybe_emit_maxc_minc): Rename
from rs6000_emit_p9_fp_minmax. Change return type to bool. Add
comments to document NaN/signed zero behavior.
(rs6000_maybe_emit_fp_cmove): Rename from rs6000_emit_p9_fp_cmove.
(have_compare_and_set_mask): New helper function.
(rs6000_emit_cmove): Update calls to new names and the new helper
function.
I discovered that we'd accept constraints on block-scope function
decls inside templates. This fixes that.
gcc/cp/
* decl.c (grokfndecl): Don't attach to local extern.
Hi,
As reported, the recently added pr96139 tests will fail on older targets
because the tests are missing the appropriate -mvsx or -maltivec options.
This adds the options and clarifies the dg-require statements.
The pr96139-c.c test needs -maltivec to work, but does not actually use
vectors, so does not require -mvsx like the others.
Sniff-regtested OK when specifying older targets on a power7 host.
--target_board=unix/'{-mcpu=power4,-mcpu=power5,-mcpu=power6,-mcpu=power7,
-mcpu=power8,-mcpu=power9}''{-m64,-m32}'"
gcc/testsuite/ChangeLog:
* gcc.target/powerpc/pr96139-a.c: Specify -mvsx option and update the
dg-require stanza to match.
* gcc.target/powerpc/pr96139-b.c: Same.
* gcc.target/powerpc/pr96139-c.c: Specify -maltivec option and update
the dg-require stanza to match.
We would like to be able to use std::align and std::assume_aligned
without pulling in everything in <memory>.
libstdc++-v3/ChangeLog:
* include/Makefile.am (bits_headers): Add new header.
* include/Makefile.in: Regenerate.
* include/bits/align.h: New file.
* include/std/memory (align): Move definition to bits/align.h.
(assume_aligned): Likewise.
In C++11 constexpr functions can only have a return statement, so we
need to fix __detail::ceil to make it valid in C++11. This can be done
by moving the comparison and increment into a new function, __ceil_impl,
and calling that with the result of the duration_cast.
This would mean the standard C++17 std::chrono::ceil function would make
two further calls, which would add too much overhead when not inlined.
For C++17 and later use a using-declaration to add chrono::ceil to
namespace __detail. For C++11 and C++14 define chrono::__detail::__ceil
as a C++11-compatible constexpr function template.
libstdc++-v3/ChangeLog:
* include/std/chrono [C++17] (chrono::__detail::ceil): Add
using declaration to make chrono::ceil available for internal
use with a consistent name.
(chrono::__detail::__ceil_impl): New function template.
(chrono::__detail::ceil): Use __ceil_impl to compare and
increment the value. Remove SFINAE constraint.
These tests are written for 256 bit vector. For -march=cascadelake,
vector size changed to 512 bit. It doubles the number of fma
instruction and test fail. Fix is to explicitly disable 512 bit
vector by passing additional option -mno-avx512f.
Tested on x86-64.
gcc/testsuite/ChangeLog:
PR target/97018
* gcc.target/i386/l_fma_double_1.c: Add option -mno-avx512f.
* gcc.target/i386/l_fma_double_2.c: Likewise.
* gcc.target/i386/l_fma_double_3.c: Likewise.
* gcc.target/i386/l_fma_double_4.c: Likewise.
* gcc.target/i386/l_fma_double_5.c: Likewise.
* gcc.target/i386/l_fma_double_6.c: Likewise.
* gcc.target/i386/l_fma_float_1.c: Likewise.
* gcc.target/i386/l_fma_float_2.c: Likewise.
* gcc.target/i386/l_fma_float_3.c: Likewise.
* gcc.target/i386/l_fma_float_4.c: Likewise.
* gcc.target/i386/l_fma_float_5.c: Likewise.
* gcc.target/i386/l_fma_float_6.c: Likewise.
Syntax errors in method definition lists could leave us in a function
scope. My recent change for block scope externs didn't like that.
This reimplements the parsing loop to finish the method definition we
started. AFAICT the original code was attempting to provide some
error recovery. Also while there, simply do the token peeking at the
top of the loop, rather than at the two(!) ends.
gcc/cp/
* parser.c (cp_parser_objc_method_definition_list): Reimplement
loop, make sure we pop scope.
gcc/testsuite/
* obj-c++.dg/syntax-error-9.mm: Adjust expected errors.
Since we now have DECL_DECLARED_CONSTINIT_P, we no longer need
LOOKUP_CONSTINIT.
gcc/cp/ChangeLog:
* cp-tree.h (LOOKUP_CONSTINIT): Remove.
(LOOKUP_REWRITTEN): Adjust.
* decl.c (duplicate_decls): Set DECL_DECLARED_CONSTINIT_P.
(check_initializer): Use DECL_DECLARED_CONSTINIT_P instead of
LOOKUP_CONSTINIT.
(cp_finish_decl): Don't set DECL_DECLARED_CONSTINIT_P. Use
DECL_DECLARED_CONSTINIT_P instead of LOOKUP_CONSTINIT.
(grokdeclarator): Set DECL_DECLARED_CONSTINIT_P.
* decl2.c (grokfield): Don't handle LOOKUP_CONSTINIT.
* parser.c (cp_parser_decomposition_declaration): Remove
LOOKUP_CONSTINIT handling.
(cp_parser_init_declarator): Likewise.
* pt.c (tsubst_expr): Likewise.
(instantiate_decl): Likewise.
* typeck2.c (store_init_value): Use DECL_DECLARED_CONSTINIT_P instead
of LOOKUP_CONSTINIT.
The fix for PR68519 in 83fd5e73b3 only
applied to condition_variable::wait_for. This problem can also apply to
condition_variable::wait_until but only if the custom clock is using a
more recent epoch so that a small enough delta can be calculated. let's
use the newly-added chrono::__detail::ceil to fix this and also make use
of that function to simplify the previous wait_for fixes.
Also, simplify the existing test case for PR68519 a little and make its
variables local so we can add a new test case for the above problem.
Unfortunately, the test would have only started failing if sufficient
time has passed since the chrono::steady_clock epoch had passed anyway,
but it's better than nothing.
libstdc++-v3/ChangeLog:
* include/std/condition_variable (condition_variable::wait_until):
Convert delta to steady_clock duration before adding to current
steady_clock time to avoid rounding errors described in PR68519.
(condition_variable::wait_for): Simplify calculation of absolute
time by using chrono::__detail::ceil in both overloads.
* testsuite/30_threads/condition_variable/members/68519.cc:
(test_wait_for): Renamed from test01. Replace unassigned val
variable with constant false. Reduce scope of mx and cv
variables to just test_wait_for function.
(test_wait_until): Add new test case.
Convert the specified duration to the target clock's duration type
before adding it to the current time in
__atomic_futex_unsigned::_M_load_when_equal_for and
_M_load_when_equal_until. This removes the risk of the timeout being
rounded down to the current time resulting in there being no wait at all
when the duration type lacks sufficient precision to hold the
steady_clock current time.
Rather than using the style of fix from PR68519, let's expose the C++17
std::chrono::ceil function as std::chrono::__detail::ceil so that it can
be used in code compiled with earlier standards versions and simplify
the fix. This was suggested by John Salmon in
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91486#c5 .
This problem has become considerably less likely to trigger since I
switched the __atomic__futex_unsigned::__clock_t reference clock from
system_clock to steady_clock and added the loop, but the consequences of
triggering it have changed too.
By my calculations it takes just over 194 days from the epoch for the
current time not to be representable in a float. This means that
system_clock is always subject to the problem (with the standard 1970
epoch) whereas steady_clock with float duration only runs out of
resolution machine has been running for that long (assuming the Linux
implementation of CLOCK_MONOTONIC.)
The recently-added loop in
__atomic_futex_unsigned::_M_load_when_equal_until turns this scenario
into a busy wait.
Unfortunately the combination of both of these things means that it's
not possible to write a test case for this occurring in
_M_load_when_equal_until as it stands.
libstdc++-v3/ChangeLog:
PR libstdc++/91486
* include/bits/atomic_futex.h
(__atomic_futex_unsigned::_M_load_when_equal_for)
(__atomic_futex_unsigned::_M_load_when_equal_until): Use
__detail::ceil to convert delta to the reference clock
duration type to avoid resolution problems.
* include/std/chrono (__detail::ceil): Move implementation
of std::chrono::ceil into private namespace so that it's
available to pre-C++17 code.
* testsuite/30_threads/async/async.cc (test_pr91486):
Test __atomic_futex_unsigned::_M_load_when_equal_for.
If std::future::wait_until is passed a time point measured against a
clock that is neither std::chrono::steady_clock nor
std::chrono::system_clock then the generic implementation of
__atomic_futex_unsigned::_M_load_when_equal_until is called which
calculates the timeout based on __clock_t and calls the
_M_load_when_equal_until method for that clock to perform the actual
wait.
There's no guarantee that __clock_t is running at the same speed as the
caller's clock, so if the underlying wait times out timeout we need to
check the timeout against the caller's clock again before potentially
looping.
Also add two extra tests to the testsuite's async.cc:
* run test03 with steady_clock_copy, which behaves identically to
chrono::steady_clock, but isn't chrono::steady_clock. This causes
the overload of __atomic_futex_unsigned::_M_load_when_equal_until
that takes an arbitrary clock to be called.
* invent test04 which uses a deliberately slow running clock in order
to exercise the looping behaviour of
__atomic_futex_unsigned::_M_load_when_equal_until described above.
libstdc++-v3/ChangeLog:
* include/bits/atomic_futex.h
(__atomic_futex_unsigned::_M_load_when_equal_until): Add
loop on generic _Clock to check the timeout against _Clock
again after _M_load_when_equal_until returns indicating a
timeout.
* testsuite/30_threads/async/async.cc: Invent slow_clock
that runs at an eleventh of steady_clock's speed. Use it
to test the user-supplied-clock variant of
__atomic_futex_unsigned::_M_load_when_equal_until works
generally with test03 and loops correctly when the timeout
time hasn't been reached in test04.
The user-visible effect of this change is that std::future::wait_for now
uses std::chrono::steady_clock to determine the timeout. This makes it
immune to changes made to the system clock. It also means that anyone
using their own clock types with std::future::wait_until will have the
timeout converted to std::chrono::steady_clock rather than
std::chrono::system_clock.
Now that use of both std::chrono::steady_clock and
std::chrono::system_clock are correctly supported for the wait timeout, I
believe that std::chrono::steady_clock is a better choice for the reference
clock that all other clocks are converted to since it is guaranteed to
advance steadily. The previous behaviour of converting to
std::chrono::system_clock risks timeouts changing dramatically when the
system clock is changed.
libstdc++-v3/ChangeLog:
* include/bits/atomic_futex.h (__atomic_futex_unsigned): Change
__clock_t typedef to use steady_clock so that unknown clocks are
synced to it rather than system_clock. Change existing __clock_t
overloads of _M_load_and_text_until_impl and
_M_load_when_equal_until to use system_clock explicitly. Remove
comment about DR 887 since these changes address that problem as
best as we currently able.
The user-visible effect of this change is for std::future::wait_until to
use CLOCK_MONOTONIC when passed a timeout of std::chrono::steady_clock
type. This makes it immune to any changes made to the system clock
CLOCK_REALTIME.
Add an overload of __atomic_futex_unsigned::_M_load_and_text_until_impl
that accepts a std::chrono::steady_clock, and correctly passes this
through to __atomic_futex_unsigned_base::_M_futex_wait_until_steady
which uses CLOCK_MONOTONIC for the timeout within the futex system call.
These functions are mostly just copies of the std::chrono::system_clock
versions with small tweaks.
Prior to this commit, a std::chrono::steady timeout would be converted
via std::chrono::system_clock which risks reducing or increasing the
timeout if someone changes CLOCK_REALTIME whilst the wait is happening.
(The commit immediately prior to this one increases the window of
opportunity for that from a short period during the calculation of a
relative timeout, to the entire duration of the wait.)
FUTEX_WAIT_BITSET was added in kernel v2.6.25. If futex reports ENOSYS
to indicate that this operation is not supported then the code falls
back to using clock_gettime(2) to calculate a relative time to wait for.
I believe that I've added this functionality in a way that it doesn't
break ABI compatibility, but that has made it more verbose and less type
safe. I believe that it would be better to maintain the timeout as an
instance of the correct clock type all the way down to a single
_M_futex_wait_until function with an overload for each clock. The
current scheme of separating out the seconds and nanoseconds early risks
accidentally calling the wait function for the wrong clock.
Unfortunately, doing this would break code that compiled against the old
header.
libstdc++-v3/ChangeLog:
* config/abi/pre/gnu.ver: Update for addition of
__atomic_futex_unsigned_base::_M_futex_wait_until_steady.
* include/bits/atomic_futex.h (__atomic_futex_unsigned_base):
Add comments to clarify that _M_futex_wait_until and
_M_load_and_test_until use CLOCK_REALTIME.
(__atomic_futex_unsigned_base::_M_futex_wait_until_steady)
(__atomic_futex_unsigned_base::_M_load_and_text_until_steady):
New member functions that use CLOCK_MONOTONIC.
(__atomic_futex_unsigned_base::_M_load_and_test_until_impl)
(__atomic_futex_unsigned_base::_M_load_when_equal_until): Add
overloads that accept a steady_clock time_point and use the
new member functions.
* src/c++11/futex.cc: Include headers required for
clock_gettime.
(futex_clock_monotonic_flag): New constant to tell futex to
use CLOCK_MONOTONIC to match existing futex_clock_realtime_flag.
(futex_clock_monotonic_unavailable): New global to store the
result of trying to use CLOCK_MONOTONIC.
(__atomic_futex_unsigned_base::_M_futex_wait_until_steady): Add
new variant of _M_futex_wait_until that uses CLOCK_MONOTONIC to
support waiting using steady_clock.
The futex system call supports waiting for an absolute time if
FUTEX_WAIT_BITSET is used rather than FUTEX_WAIT. Doing so provides two
benefits:
1. The call to gettimeofday is not required in order to calculate a
relative timeout.
2. If someone changes the system clock during the wait then the futex
timeout will correctly expire earlier or later. Currently that only
happens if the clock is changed prior to the call to gettimeofday.
According to futex(2), support for FUTEX_CLOCK_REALTIME was added in the
v2.6.28 Linux kernel and FUTEX_WAIT_BITSET was added in v2.6.25. To
ensure that the code still works correctly with earlier kernel versions,
an ENOSYS error from futex[1] results in the
futex_clock_realtime_unavailable flag being set. This flag is used to
avoid the unnecessary unsupported futex call in the future and to fall
back to the previous gettimeofday and relative time implementation.
glibc applied an equivalent switch in pthread_cond_timedwait to use
FUTEX_CLOCK_REALTIME and FUTEX_WAIT_BITSET rather than FUTEX_WAIT for
glibc-2.10 back in 2009. See
glibc:cbd8aeb836c8061c23a5e00419e0fb25a34abee7
The futex_clock_realtime_unavailable flag is accessed using
std::memory_order_relaxed to stop it becoming a bottleneck. If the
first two calls to _M_futex_wait_until happen to happen simultaneously
then the only consequence is that both will try to use
FUTEX_CLOCK_REALTIME, both risk discovering that it doesn't work and, if
so, both set the flag.
[1] This is how glibc's nptl-init.c determines whether these flags are
supported.
libstdc++-v3/ChangeLog:
* src/c++11/futex.cc: Add new constants for required futex
flags. Add futex_clock_realtime_unavailable flag to store
result of trying to use FUTEX_CLOCK_REALTIME.
(__atomic_futex_unsigned_base::_M_futex_wait_until): Try to
use FUTEX_WAIT_BITSET with FUTEX_CLOCK_REALTIME and only
fall back to using gettimeofday and FUTEX_WAIT if that's not
supported.
Add tests for waiting for the future using both chrono::steady_clock and
chrono::system_clock in preparation for dealing with those clocks
properly in futex.cc.
libstdc++-v3/ChangeLog:
* testsuite/30_threads/async/async.cc (test02): Test steady_clock
with std::future::wait_until.
(test03): Add new test templated on clock type waiting for future
associated with async to resolve.
(main): Call test03 to test both system_clock and steady_clock.
When building with -fno-exceptions, bad_exception_allowed is set but
not used, causing a warning during the build.
This patch adds __attribute__((unused)) to avoid it.
2020-09-11 Torbjörn SVENSSON <torbjorn.svensson@st.com>
Christophe Lyon <christophe.lyon@linaro.org>
libstdc++-v3/
* libsupc++/eh_call.cc: Avoid warning with -fno-exceptions.
When building with -fno-exceptions, __throw_exception_again expands to
nothing, causing a "suggest braces around empty body in an 'if'
statement" warning.
This patch adds braces, like what was done in eh_personality.cc in svn
r193295 (git g:54ba39f599fc2f3d59fd3cd828a301ce9b731a20)
2020-09-11 Torbjörn SVENSSON <torbjorn.svensson@st.com>
Christophe Lyon <christophe.lyon@linaro.org>
libstdc++-v3/
* libsupc++/eh_call.cc: Avoid warning with -fno-exceptions.
The previous re-org made the cost of SLP vector stmts in loop
vectorization ignored. The following rectifies this mistake.
2020-09-11 Richard Biener <rguenther@suse.de>
PR tree-optimization/97020
* tree-vect-slp.c (vect_slp_analyze_operations): Apply
SLP costs when doing loop vectorization.
gcc/jit/ChangeLog
2020-08-01 Andrea Corallo <andrea.corallo@arm.com>
* docs/topics/compatibility.rst (LIBGCCJIT_ABI_14): New ABI tag.
* docs/topics/expressions.rst (gcc_jit_global_set_initializer):
Document new entry point in section 'Global variables'.
* jit-playback.c (global_new_decl, global_finalize_lvalue): New
method.
(playback::context::new_global): Make use of global_new_decl,
global_finalize_lvalue.
(load_blob_in_ctor): New template function in use by the
following.
(playback::context::new_global_initialized): New method.
* jit-playback.h (class context): Decl 'new_global_initialized',
'global_new_decl', 'global_finalize_lvalue'.
(lvalue::set_initializer): Add implementation.
* jit-recording.c (recording::memento_of_get_pointer::get_size)
(recording::memento_of_get_type::get_size): Add implementation.
(recording::global::write_initializer_reproducer): New function in
use by 'recording::global::write_reproducer'.
(recording::global::replay_into)
(recording::global::write_to_dump)
(recording::global::write_reproducer): Handle
initialized case.
* jit-recording.h (class type): Decl 'get_size' and
'num_elements'.
* libgccjit++.h (class lvalue): Declare new 'set_initializer'
method.
(class lvalue): Decl 'is_global' and 'set_initializer'.
(class global) Decl 'write_initializer_reproducer'. Add
'm_initializer', 'm_initializer_num_bytes' fields. Implement
'set_initializer'. Add a destructor to free 'm_initializer'.
* libgccjit.c (gcc_jit_global_set_initializer): New function.
* libgccjit.h (gcc_jit_global_set_initializer): New function
declaration.
* libgccjit.map (LIBGCCJIT_ABI_14): New ABI tag.
gcc/testsuite/ChangeLog
2020-08-01 Andrea Corallo <andrea.corallo@arm.com>
* jit.dg/all-non-failing-tests.h: Add test-blob.c.
* jit.dg/test-global-set-initializer.c: New testcase.
Add nvptx support to libatomic.
Given that atomic_test_and_set is not implemented for nvptx (PR96964), the
compiler translates __atomic_test_and_set falling back onto the "Failing all
else, assume a single threaded environment and simply perform the operation"
case in expand_atomic_test_and_set, so it doesn't map onto an actual atomic
operation.
Still, that counts as supported for the configure test of libatomic, so we
end up with HAVE_ATOMIC_TAS_1/2/4/8/16 == 1, and the corresponding
__atomic_test_and_set_1/2/4/8/16 in libatomic all using that non-atomic
implementation.
Fix this by adding an atomic_test_and_set expansion for nvptx, that uses
libatomics __atomic_test_and_set_1.
This again makes the configure tests for HAVE_ATOMIC_TAS_1/2/4/8/16 fail, so
instead we use this case in tas_n.c:
...
/* If this type is smaller than word-sized, fall back to a word-sized
compare-and-swap loop. */
bool
SIZE(libat_test_and_set) (UTYPE *mptr, int smodel)
...
which for __atomic_test_and_set_8 uses INVERT_MASK_8.
Add INVERT_MASK_8 in libatomic_i.h, as well as MASK_8.
Tested libatomic testsuite on nvptx.
gcc/ChangeLog:
PR target/96964
* config/nvptx/nvptx.md (define_expand "atomic_test_and_set"): New
expansion.
libatomic/ChangeLog:
PR target/96898
* configure.tgt: Add nvptx.
* libatomic_i.h (MASK_8, INVERT_MASK_8): New macro definition.
* config/nvptx/host-config.h: New file.
* config/nvptx/lock.c: New file.
This prevents execution failures caused by partially overlapping input and
output registers. This is the same solution already used for DImode.
gcc/ChangeLog:
* config/gcn/gcn.c (gcn_hard_regno_mode_ok): Align TImode registers.
* config/gcn/gcn.md: Assert that TImode registers do not early clobber.
This tries to improve BB vectorization dumps by providing more
precise locations. Currently the vect_location is simply the
very last stmt in a basic-block that has a location. So for
double a[4], b[4];
int x[4], y[4];
void foo()
{
a[0] = b[0]; // line 5
a[1] = b[1];
a[2] = b[2];
a[3] = b[3];
x[0] = y[0]; // line 9
x[1] = y[1];
x[2] = y[2];
x[3] = y[3];
} // line 13
we show the user with -O3 -fopt-info-vec
t.c:13:1: optimized: basic block part vectorized using 16 byte vectors
while with the patch we point to both independently vectorized
opportunities:
t.c:5:8: optimized: basic block part vectorized using 16 byte vectors
t.c:9:8: optimized: basic block part vectorized using 16 byte vectors
there's the possibility that the location regresses in case the
root stmt in the SLP instance has no location. For a SLP subgraph
with multiple entries the location also chooses one entry at random,
not sure in which case we want to dump both.
Still as the plan is to extend the basic-block vectorization
scope from single basic-block to multiple ones this is a first
step to preserve something sensible.
Implementation-wise this makes both costing and code-generation
happen on the subgraphs as analyzed.
2020-09-11 Richard Biener <rguenther@suse.de>
* tree-vectorizer.h (_slp_instance::location): New method.
(vect_schedule_slp): Adjust prototype.
* tree-vectorizer.c (vec_info::remove_stmt): Adjust
the BB region begin if we removed the stmt it points to.
* tree-vect-loop.c (vect_transform_loop): Adjust.
* tree-vect-slp.c (_slp_instance::location): Implement.
(vect_analyze_slp_instance): For BB vectorization set
vect_location to that of the instance.
(vect_slp_analyze_operations): Likewise.
(vect_bb_vectorization_profitable_p): Remove wrapper.
(vect_slp_analyze_bb_1): Remove cost check here.
(vect_slp_region): Cost check and code generate subgraphs separately,
report optimized locations and missed optimizations due to
profitability for each of them.
(vect_schedule_slp): Get the vector of SLP graph entries to
vectorize as argument.
This is a regression present on the mainline and 10 branch: the compiler
aborts on code accessing a component of a packed record type whose type
is a packed discriminated record type with variant part.
gcc/ada/ChangeLog:
* gcc-interface/utils.c (type_has_variable_size): New function.
(create_field_decl): In the packed case, also force byte alignment
when the type of the field has variable size.
gcc/testsuite/ChangeLog:
* gnat.dg/pack27.adb: New test.
* gnat.dg/pack27_pkg.ads: New helper.
This adds a missing stride entry for bit-packed arrays of record types.
gcc/ada/ChangeLog:
* gcc-interface/misc.c (get_array_bit_stride): Return TYPE_ADA_SIZE
for record and union types.
GDB can now deal with the DWARF representation just fine.
gcc/ada/ChangeLog:
* gcc-interface/misc.c (gnat_get_fixed_point_type): Bail out only
when the GNAT encodings are specifically used.
This is a regression present on mainline, 10 and 9 branches: the compiler
goes into an infinite recursion eventually exhausting the stack for the
declaration of a discriminated record type with an array component having
a discriminant as bound and an index type that is an enumeration type with
a non-standard representation clause.
gcc/ada/ChangeLog:
* gcc-interface/decl.c (gnat_to_gnu_entity) <E_Array_Subtype>: Only
create extra subtypes for discriminants if the RM size of the base
type of the index type is lower than that of the index type.
gcc/testsuite/ChangeLog:
* gnat.dg/specs/discr7.ads: New test.
