This optimizes signed right shift by BITSIZE-1 into a cmlt operation which is
more optimal because generally compares have a higher throughput than shifts.
On AArch64 the result of the shift would have been either -1 or 0 which is the
results of the compare.
i.e.
void e (int * restrict a, int *b, int n)
{
for (int i = 0; i < n; i++)
b[i] = a[i] >> 31;
}
now generates:
.L4:
ldr q0, [x0, x3]
cmlt v0.4s, v0.4s, #0
str q0, [x1, x3]
add x3, x3, 16
cmp x4, x3
bne .L4
instead of:
.L4:
ldr q0, [x0, x3]
sshr v0.4s, v0.4s, 31
str q0, [x1, x3]
add x3, x3, 16
cmp x4, x3
bne .L4
Thanks,
Tamar
gcc/ChangeLog:
* config/aarch64/aarch64-simd.md (aarch64_simd_ashr<mode>): Add case cmp
case.
* config/aarch64/constraints.md (D1): New.
gcc/testsuite/ChangeLog:
* gcc.target/aarch64/shl-combine-2.c: New test.
* gcc.target/aarch64/shl-combine-3.c: New test.
* gcc.target/aarch64/shl-combine-4.c: New test.
* gcc.target/aarch64/shl-combine-5.c: New test.
When doing a (narrowing) right shift by half the width of the original type then
we are essentially shuffling the top bits from the first number down.
If we have a hi/lo pair we can just use a single shuffle instead of needing two
shifts.
i.e.
typedef short int16_t;
typedef unsigned short uint16_t;
void foo (uint16_t * restrict a, int16_t * restrict d, int n)
{
for( int i = 0; i < n; i++ )
d[i] = (a[i] * a[i]) >> 16;
}
now generates:
.L4:
ldr q0, [x0, x3]
umull v1.4s, v0.4h, v0.4h
umull2 v0.4s, v0.8h, v0.8h
uzp2 v0.8h, v1.8h, v0.8h
str q0, [x1, x3]
add x3, x3, 16
cmp x4, x3
bne .L4
instead of
.L4:
ldr q0, [x0, x3]
umull v1.4s, v0.4h, v0.4h
umull2 v0.4s, v0.8h, v0.8h
sshr v1.4s, v1.4s, 16
sshr v0.4s, v0.4s, 16
xtn v1.4h, v1.4s
xtn2 v1.8h, v0.4s
str q1, [x1, x3]
add x3, x3, 16
cmp x4, x3
bne .L4
Thanks,
Tamar
gcc/ChangeLog:
* config/aarch64/aarch64-simd.md
(*aarch64_<srn_op>topbits_shuffle<mode>_le): New.
(*aarch64_topbits_shuffle<mode>_le): New.
(*aarch64_<srn_op>topbits_shuffle<mode>_be): New.
(*aarch64_topbits_shuffle<mode>_be): New.
* config/aarch64/predicates.md
(aarch64_simd_shift_imm_vec_exact_top): New.
gcc/testsuite/ChangeLog:
* gcc.target/aarch64/shrn-combine-10.c: New test.
* gcc.target/aarch64/shrn-combine-5.c: New test.
* gcc.target/aarch64/shrn-combine-6.c: New test.
* gcc.target/aarch64/shrn-combine-7.c: New test.
* gcc.target/aarch64/shrn-combine-8.c: New test.
* gcc.target/aarch64/shrn-combine-9.c: New test.
This patch implements support for the in_reduction clause for Fortran.
It also includes more completion of the taskgroup construct inside the
Fortran front-end, thus allowing task_reduction to work for task and
target constructs.
gcc/fortran/ChangeLog:
* openmp.c (gfc_match_omp_clause_reduction): Add 'openmp_target' default
false parameter. Add 'always,tofrom' map for OMP_LIST_IN_REDUCTION case.
(gfc_match_omp_clauses): Add 'openmp_target' default false parameter,
adjust call to gfc_match_omp_clause_reduction.
(match_omp): Adjust call to gfc_match_omp_clauses
* trans-openmp.c (gfc_trans_omp_taskgroup): Add call to
gfc_match_omp_clause, create and return block.
gcc/ChangeLog:
* omp-low.c (omp_copy_decl_2): For !ctx, use record_vars to add new copy
as local variable.
(scan_sharing_clauses): Place copy of OMP_CLAUSE_IN_REDUCTION decl in
ctx->outer instead of ctx.
gcc/testsuite/ChangeLog:
* gfortran.dg/gomp/reduction4.f90: Adjust omp target in_reduction' scan
pattern.
libgomp/ChangeLog:
* testsuite/libgomp.fortran/target-in-reduction-1.f90: New test.
* testsuite/libgomp.fortran/target-in-reduction-2.f90: New test.
Tune the case-values-threshold setting for modern cores. A value of 11 improves
SPECINT2017 by 0.2% and reduces codesize by 0.04%. With -Os use value 8 which
reduces codesize by 0.07%.
2021-10-18 Wilco Dijkstra <wdijkstr@arm.com>
gcc/
* config/aarch64/aarch64.c (aarch64_case_values_threshold):
Change to 8 with -Os, 11 otherwise.
Enable the fast shift feature in Neoverse V1 and N2 tunings as well.
2021-10-20 Wilco Dijkstra <wdijkstr@arm.com>
gcc/
* config/aarch64/aarch64.c (neoversev1_tunings):
Enable AARCH64_EXTRA_TUNE_CHEAP_SHIFT_EXTEND.
(neoversen2_tunings): Likewise.
* testsuite/lib/libffi.exp (load_gcc_lib): Load library from GCC
testsuite.
Load target-supports.exp and target-supports-dg.exp.
(libffi-init): Use libraries in GCC build tree.
(libffi_target_compile): Link with -shared-libgcc -lstdc++ for
C++ sources.
Add scripts for syncing with libffi upstream:
1. Clone libffi repo.
2. Checkout the specific commit.
3. Remove the unused files.
4. Add new files and remove old files if needed.
* HOWTO_MERGE: New file.
* autogen.sh: Likewise.
* merge.sh: Likewise.
As preparation for a new global object that will encapsulate
asm_out_file, we would need to live with a macro that will
define asm_out_file as casm->out_file and thus the name
can't be used in function arguments.
gcc/ChangeLog:
* config/arm/arm.c (arm_unwind_emit_sequence): Do not declare
already declared global variable.
(arm_unwind_emit_set): Use out_file as function argument.
(arm_unwind_emit): Likewise.
* config/darwin.c (machopic_output_data_section_indirection): Likewise.
(machopic_output_stub_indirection): Likewise.
(machopic_output_indirection): Likewise.
(machopic_finish): Likewise.
* config/i386/i386.c (ix86_asm_output_function_label): Likewise.
* config/i386/winnt.c (i386_pe_seh_unwind_emit): Likewise.
* config/ia64/ia64.c (process_epilogue): Likewise.
(process_cfa_adjust_cfa): Likewise.
(process_cfa_register): Likewise.
(process_cfa_offset): Likewise.
(ia64_asm_unwind_emit): Likewise.
* config/s390/s390.c (s390_asm_output_function_label): Likewise.
This avoids running into the assert in compute_distributive_range when
starting the analysis with operations in a trapping type.
2021-10-20 Richard Biener <rguenther@suse.de>
PR tree-optimization/102853
* tree-data-ref.c (split_constant_offset_1): Bail out
immediately if the expression traps on overflow.
These are some random obvious cleanups to the threading dumps, since
it seems I'm not the only one looking at dumps these days.
The "just threaded" debugging message is redundant since there's
already an equivalent "Registering jump thread" message.
The "about to thread" message is actually confusing, because the source
block doesn't match the IL, since the CFG update is mid-flight.
Tested on x86-64 Linux.
gcc/ChangeLog:
* tree-ssa-threadupdate.c (back_jt_path_registry::adjust_paths_after_duplication):
Remove superflous debugging message.
(back_jt_path_registry::duplicate_thread_path): Same.
gcc/ada/
* libgnat/s-widlllu.ads: Mark in SPARK.
* libgnat/s-widllu.ads: Likewise.
* libgnat/s-widuns.ads: Likewise.
* libgnat/s-widthu.adb: Add ghost code and a
pseudo-postcondition.
gcc/ada/
* libgnat/a-nbnbin__ghost.adb (Signed_Conversions,
Unsigned_Conversions): Mark subprograms as not imported.
* libgnat/a-nbnbin__ghost.ads: Provide a dummy body.
gcc/ada/
* sem_eval.adb (Eval_Type_Conversion): If the target subtype is
a static floating-point subtype and the result is a real literal,
consider its machine-rounded value to raise Constraint_Error.
(Test_In_Range): Turn local variables into constants.
gcc/ada/
* sem_eval.ads (Machine_Number): New inline function.
* sem_eval.adb (Machine_Number): New function body implementing
the machine rounding operation specified by RM 4.9(38/2).
(Check_Non_Static_Context): Call Machine_Number and set the
Is_Machine_Number flag consistently on the resulting node.
* sem_attr.adb (Eval_Attribute) <Attribute_Machine>: Likewise.
* checks.adb (Apply_Float_Conversion_Check): Call Machine_Number.
(Round_Machine): Likewise.
gcc/ada/
* sem_ch6.adb (Check_Return_Construct_Accessibility): Modify
generation of accessibility checks to be more consolidated and
get triggered properly in required cases.
* sem_util.adb (Accessibility_Level): Add extra check within
condition to handle aliased formals properly in more cases.
gcc/ada/
* exp_ch7.adb (Make_Final_Call): Detect expanded protected types
and use original protected type in order to calculate
appropriate finalization routine.
gcc/ada/
* atree.ads: Comment improvements. How is a "completely new
node" different from a "new node"? Document default values
corresponding to field types.
* exp_ch7.adb (Process_Tagged_Type_Declaration): Use
higher-level Scope_Depth instead of Scope_Depth_Value. Remove
confusing comment: not clear what a "true" library level package
is.
* uintp.adb (Image_Out): Print No_Uint in a more readable way.
* gen_il-gen.adb, gen_il-gen-gen_entities.adb,
gen_il-gen-gen_nodes.adb, gen_il-types.ads: Tighten up the
subtypes of fields whose type is Uint, where possible; use
more-constrained subtypes such as Unat.
* einfo-utils.adb, einfo-utils.ads, exp_attr.adb,
exp_ch3.adb, exp_intr.adb, exp_unst.adb, exp_util.adb,
freeze.adb, repinfo.adb, sem.adb, sem_ch12.adb, sem_ch13.adb,
sem_ch3.adb, sem_ch8.adb, sem_util.adb, sprint.adb, treepr.adb:
No longer use Uint_0 to indicate "unknown" or "not yet known"
for various fields whose type is Uint. Use No_Uint for that,
except in a small number of legacy cases that cause test
failures. Protect many queries of such fields with calls to
Known_... functions. Improve comments.
* exp_aggr.adb: Likewise.
(Is_OK_Aggregate): Check whether Csiz is present.
(Aggr_Assignment_OK_For_Backend): Ensure we do not access an
uninitialized size.
* exp_strm.adb (Build_Elementary_Input_Call,
Build_Elementary_Write_Call): Check whether P_Size is present.
* cstand.adb: Leave Component_Size of Any_Composite unknown.
Similar for RM_Size of Standard_Exception_Type. These should
not be used.
* einfo.ads: Comment improvements.
* exp_disp.ads: Minor.
* gen_il-internals.ads, gen_il-internals.adb: Minor.
* sinfo-utils.adb: Take advantage of full-coverage rules.
* types.h: Minor.
gcc/ada/
* sem_ch6.adb: Add with and use of Warnsw.
(Check_Conformance): Report a warning when subtypes or
designated subtypes of formal parameters or result subtypes
denote different declarations between the spec and body of the
(Subprogram_Subtypes_Have_Same_Declaration): New function nested
within Check_Conformance that determines whether two subtype
entities referenced in a subprogram come from the same
declaration. Returns True immediately if the subprogram is in a
generic instantiation, or the subprogram is marked Is_Internal
or is declared in an internal (GNAT library) unit, or GNAT_Mode
is enabled, otherwise compares the nonlimited views of the
entities (or their designated subtypes' nonlimited views in the
anonymous access cases).
(Nonlimited_View_Of_Subtype): New function nested within
function Subprogram_Subtypes_Have_Same_Declaration that returns
Non_Limited_View of a type or subtype that is an incomplete or
class-wide type that comes from a limited of a
package (From_Limited_With is True for the entity), or returns
Full_View when the nonlimited view is an incomplete type.
Otherwise returns the entity passed in.
* warnsw.ads (Warn_On_Pedantic_Checks): New warning flag.
(type Warning_Record): New component Warn_On_Pedantic_Checks.
* warnsw.adb (All_Warnings): Set Warn_On_Pedantic_Checks from
parameter Setting.
(Restore_Warnings): Restore the value of the
Warn_On_Pedantic_Checks flag.
(Save_Warnings): Save the value of the Warn_On_Pedantic_Checks
flag.
(Set_Underscore_Warning_Switch): Add settings of the
Warn_On_Pedantic flag according to the switch ("-gnatw_p" vs.
"-gnatw_P").
* doc/gnat_ugn/building_executable_programs_with_gnat.rst: Add
documentation of new switches -gnatw_p and -gnatw_P (warnings
for pedantic checks).
* gnat_ugn.texi: Regenerate.
* usage.adb: Add Warn_On_Pedantic_Checks.
gcc/ada/
* sem_eval.ads (Check_Non_Static_Context): Update documentation.
* sem_eval.adb (In_Any_Integer_Context): Change parameter type,
adjust accordingly and remove unreachable case.
(Eval_Integer_Literal): Consider the node kind throughout and
trim down verbose condition.
gcc/ada/
* sem_ch4.adb (Analyze_QUantified_Expression): Issue warning on
conjunct/disjunct sub-expression of the full expression inside a
quantified expression, when it does not reference the quantified
variable.
The removal of --param=max-fsm-thread-length is causing code
explosion. I thought that --param=max-fsm-thread-path-insns was a
better gague for path profitability than raw BB length, but it turns
out that we don't take into account PHIs when estimating the number of
statements.
In this PR, we have a sequence of very large PHIs that have us
traversing extremely large paths that blow up the compilation.
We could fix this a couple of different ways. We could avoid
traversing more than a certain number of PHI arguments, or ignore
large PHIs altogether. The old implementation certainly had this
knob, and we could cut things off before we even got to the ranger.
We could also adjust the instruction estimation to take into account
PHIs, but I'm sure we'll mess something else in the process ;-).
The easiest thing to do is just restore the knob.
At a later time we could tweak this further, for instance,
disregarding empty blocks in the count. BTW, this is the reason I
didn't chop things off in the lowlevel registry for all threaders: the
forward threader can't really explore too deep paths, but it could
theoretically get there while threading over empty blocks.
This fixes 102814, 102852, and I bet it solves the Linux kernel cross
compile issue.
Tested on x86-64 Linux.
gcc/ChangeLog:
PR tree-optimization/102814
* doc/invoke.texi: Document --param=max-fsm-thread-length.
* params.opt: Add --param=max-fsm-thread-length.
* tree-ssa-threadbackward.c
(back_threader_profitability::profitable_path_p): Fail on paths
longer than max-fsm-thread-length.
This is a regression present on the mainline in the form of -fcompare-debug
failure at -O3 on a compiler-generated testcase. Fixed by disregarding a
debug statement in the last position of a basic block to reset the current
location for the outgoing edges.
gcc/
PR middle-end/102764
* cfgexpand.c (expand_gimple_basic_block): Disregard a final debug
statement to reset the current location for the outgoing edges.
gcc/testsuite/
* gcc.dg/pr102764.c: New test.
This addresses PR ada/100486, which is the bootstrap failure of GCC 11 for
32-bit Windows in the MSYS setup. The PR shows that we cannot rely on
exception propagation being operational during the bootstrap, at least on
the 11 branch, so fix this by removing the problematic raise statement.
gcc/ada/
PR ada/100486
* sem_prag.adb (Check_Valid_Library_Unit_Pragma): Do not raise an
exception as part of the bootstrap.
If GOMP_HAVE_EFFICIENT_ALIGNED_ALLOC is not defined, the intent was to
treat the split of the structure between first cacheline (64 bytes)
as mostly write-once, use afterwards and second cacheline as rw just
as an optimization. But as has been reported, with vectorization enabled
at -O2 it can now result in aligned vector 16-byte or larger stores.
When not having posix_memalign/aligned_alloc/memalign or other similar API,
alloc.c emulates it but it needs to allocate extra memory for the dynamic
realignment.
So, for the GOMP_HAVE_EFFICIENT_ALIGNED_ALLOC not defined case, this patch
stops using aligned (64) attribute in the middle of the structure and instead
inserts padding that puts the second half of the structure at offset 64 bytes.
And when GOMP_HAVE_EFFICIENT_ALIGNED_ALLOC is defined, usually it was allocated
as aligned, but for the orphaned case it could still be allocated just with
gomp_malloc without guaranteed proper alignment.
2021-10-20 Jakub Jelinek <jakub@redhat.com>
PR libgomp/102838
* libgomp.h (struct gomp_work_share_1st_cacheline): New type.
(struct gomp_work_share): Only use aligned(64) attribute if
GOMP_HAVE_EFFICIENT_ALIGNED_ALLOC is defined, otherwise just
add padding before lock to ensure lock is at offset 64 bytes
into the structure.
(gomp_workshare_struct_check1, gomp_workshare_struct_check2):
New poor man's static assertions.
* work.c (gomp_work_share_start): Use gomp_aligned_alloc instead of
gomp_malloc if GOMP_HAVE_EFFICIENT_ALIGNED_ALLOC.
