2018-02-09  Vladimir Makarov  <vmakarov@redhat.com>

	PR rtl-optimization/57193
	* ira-color.c (struct allocno_color_data): Add member
	conflict_allocno_hard_prefs.
	(update_conflict_allocno_hard_prefs): New.
	(bucket_allocno_compare_func): Add a preference based on
	conflict_allocno_hard_prefs.
	(push_allocno_to_stack): Update conflict_allocno_hard_prefs.
	(color_allocnos): Remove a dead code.  Initiate
	conflict_allocno_hard_prefs.  Call update_costs_from_prefs.

2018-02-09  Vladimir Makarov  <vmakarov@redhat.com>

	PR rtl-optimization/57193
	* gcc.target/i386/57193.c: New.

From-SVN: r257537

	PR target/84226
	* config/rs6000/vsx.md (p9_xxbrq_v16qi): Change input operand
	constraint from =wa to wa.  Avoid a subreg on the output operand,
	instead use a pseudo and subreg it in a move.
	(p9_xxbrd_<mode>): Changed to ...
	(p9_xxbrd_v2di): ... this insn, without VSX_D iterator.
	(p9_xxbrd_v2df): New expander.
	(p9_xxbrw_<mode>): Changed to ...
	(p9_xxbrw_v4si): ... this insn, without VSX_W iterator.
	(p9_xxbrw_v4sf): New expander.

	* gcc.target/powerpc/pr84226.c: New test.

From-SVN: r257536

	* gcc.target/powerpc/builtins-1-be.c <vclzb>: Rename duplicate test
	from this to...
	<vclzd>: ...this.

From-SVN: r257535

gcc/c-family/ChangeLog:

	PR lto/84212
	* c.opt (-Wstringop-overflow, -Warray-bounds): Add LTO.
	(-Walloc-size-larger-than, -Wformat-truncation=): Same.
	(-Wmaybe-uninitialized, -Wnonnull, -Wrestrict): Same.
	(-Wstrict-overflow, -Wsuggest-attribute): Same.
	(-Wuninitialized): Same.

gcc/testsuite/ChangeLog:

	PR lto/84212
	* gcc.dg/lto/pr84212_0.c: New test file.
	* gcc.dg/lto/pr84212_1.c: Same.

From-SVN: r257534

2018-02-09  Sebastian Perta  <sebastian.perta@renesas.com>

	*config/rx.md: updated "movsicc" expand to be matched by GCC
	*testsuite/gcc.target/rx/movsicc.c: new test case

From-SVN: r257533

gcc/
	PR target/83926
	* config/rs6000/vsx.md (vsx_mul_v2di): Handle generating a 64-bit
	multiply in 32-bit mode.
	(vsx_div_v2di): Handle generating a 64-bit signed divide in 32-bit mode.
	(vsx_udiv_v2di): Handle generating a 64-bit unsigned divide in 32-bit
	mode.

gcc/testsuite/
	PR target/83926
	* gcc.target/powerpc/pr83926.c: New test.
	* gcc.target/powerpc/builtins-1-be.c: Filter out gimple folding disabled
	message.  Fix test for running in 32-bit mode.

From-SVN: r257531

2018-02-09  Sebastian Perta  <sebastian.perta@renesas.com>

	* config/rx/constraints.md: added new constraint CALL_OP_SYMBOL_REF 
	to allow or block "symbol_ref" depending on value of TARGET_JSR
	* config/rx/rx.md: use CALL_OP_SYMBOL_REF in call_internal and 
	call_value_internal insns

From-SVN: r257529

From-SVN: r257527

This patch restricts the set of cases in which we allow the generation of
location attributes for variables that are not defined in the current unit.
For such variables with complex DECL_VALUE_EXPR trees, generating a location
attribute can end up creating relocations to text symbols in the debug section
of LTO object files, which is not valid.

gcc/
	PR lto/84213
	* dwarf2out.c (is_trivial_indirect_ref): New function.
	(dwarf2out_late_global_decl): Do not generate a location
	attribute for variables that have a non-trivial DECL_VALUE_EXPR
	and that are not defined in the current unit.

From-SVN: r257526

optabs.c (prepare_cmp_insn): Try harder to emit a direct comparison instead of a libcall for UNORDERED.

	* optabs.c (prepare_cmp_insn): Try harder to emit a direct comparison
	instead of a libcall for UNORDERED.

From-SVN: r257525

re PR target/82641 (Unable to enable crc32 for a certain function with target attribute on ARM (aarch32))

2018-02-09  Tamar Christina  <tamar.christina@arm.com>

	PR target/82641
	* config/arm/arm-c.c (arm_cpu_builtins): Un-define __ARM_FEATURE_LDREX,
	__ARM_ARCH_PROFILE, __ARM_ARCH_ISA_THUMB, __ARM_FP and __ARM_NEON_FP.

gcc/testsuite
2018-02-09  Tamar Christina  <tamar.christina@arm.com>

	PR target/82641
	* gcc.target/arm/pragma_arch_switch_2.c: Use armv6 and armv5t.

From-SVN: r257524

gcc/ChangeLog:

2018-02-09  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>

	PR target/PR84295
	* config/s390/s390.c (s390_set_current_function): Invoke
	s390_indirect_branch_settings also if fndecl didn't change.

gcc/testsuite/ChangeLog:

2018-02-09  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>

	PR target/PR84295
	* gcc.target/s390/pr84295.c: New test.

From-SVN: r257522

2018-02-09  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/77522
	* g++.dg/cpp1y/lambda-init16.C: New.

From-SVN: r257521

LVU requires the zero-length (pseudo) insns's length to reflect
reality.  If they don't, it may assume there's a PC change where there
isn't any, and then a view-aware assembler will detect the problem and
complain about out-of-sync views.

ppc blockage pseudo-insns did not have the length attribute explicitly
set in them, so they inherited the attribute's default value, and that
was nonzero.

for  gcc/ChangeLog

	* config/rs6000/rs6000.md (blockage): Set length to zero.

From-SVN: r257520

From-SVN: r257519

2018-02-09  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/84278
	* gcc.target/i386/pr84278.c: Adjust regex.

From-SVN: r257518

	* c-ada-spec.c (dump_ada_declaration): Do not generate the 'constant'
	keyword for components.

From-SVN: r257517

	PR tree-optimization/84232
	* gcc.dg/tree-ssa/ssa-dom-cse-2.c: Add -mtune-generic on x86.

From-SVN: r257516

	PR sanitizer/84285
	* gcc.c (STATIC_LIBASAN_LIBS, STATIC_LIBTSAN_LIBS,
	STATIC_LIBLSAN_LIBS, STATIC_LIBUBSAN_LIBS): Handle -static like
	-static-lib*san.

From-SVN: r257515

	PR debug/84252
	* var-tracking.c (vt_add_function_parameter): Punt for non-onepart
	PARALLEL incoming that failed vt_get_decl_and_offset check.

	* gcc.target/aarch64/pr84252.c: New test.

From-SVN: r257514

re PR middle-end/84237 (xen build faiulre only zero initializers are allowed in section '.bss.page_aligned.const')

	PR middle-end/84237
	* output.h (bss_initializer_p): Add NAMED argument, defaulted to false.
	* varasm.c (bss_initializer_p): Add NAMED argument, if true, ignore
	TREE_READONLY bit.
	(get_variable_section): For decls in named .bss* sections pass true as
	second argument to bss_initializer_p.

	* gcc.dg/pr84237.c: New test.

From-SVN: r257513

	PR c++/83659
	* fold-const.c (fold_indirect_ref_1): Use VECTOR_TYPE_P macro.
	Formatting fixes.  Verify first that tree_fits_poly_int64_p (op01).
	Sync some changes from cxx_fold_indirect_ref.

	* constexpr.c (cxx_fold_indirect_ref): Sync some changes from
	fold_indirect_ref_1, including poly_*int64.  Verify first that
	tree_fits_poly_int64_p (op01).  Formatting fixes.

	* g++.dg/torture/pr83659.C: New test.

Co-Authored-By: Jakub Jelinek <jakub@redhat.com>

From-SVN: r257512

Output DW_AT_entry_pc based on markers.

Introduce DW_AT_GNU_entry_view as a DWARF extension.

If views are enabled are we're not in strict compliance mode, output
DW_AT_GNU_entry_view if it might be nonzero.

This patch depends on SFN and LVU patchsets, and on the IEPM patch that
introduces the inline_entry debug hook.

for  include/ChangeLog

	* dwarf2.def (DW_AT_GNU_entry_view): New.

for  gcc/ChangeLog

	* cfgexpand.c (expand_gimple_basic_block): Handle inline entry
	markers.
	* dwarf2out.c (dwarf2_debug_hooks): Enable inline_entry hook.
	(BLOCK_INLINE_ENTRY_LABEL): New.
	(dwarf2out_var_location): Disregard inline entry markers.
	(inline_entry_data): New struct.
	(inline_entry_data_hasher): New hashtable type.
	(inline_entry_data_hasher::hash): New.
	(inline_entry_data_hasher::equal): New.
	(inline_entry_data_table): New variable.
	(add_high_low_attributes): Add DW_AT_entry_pc and
	DW_AT_GNU_entry_view attributes if a pending entry is found
	in inline_entry_data_table.  Add old entry_pc attribute only
	if debug nonbinding markers are disabled.
	(gen_inlined_subroutine_die): Set BLOCK_DIE if nonbinding
	markers are enabled.
	(block_within_block_p, dwarf2out_inline_entry): New.
	(dwarf2out_finish): Check that no entries remained in
	inline_entry_data_table.
	* final.c (reemit_insn_block_notes): Handle inline entry notes.
	(final_scan_insn, notice_source_line): Likewise.
	(rest_of_clean_state): Skip inline entry markers.
	* gimple-pretty-print.c (dump_gimple_debug): Handle inline entry
	markers.
	* gimple.c (gimple_build_debug_inline_entry): New.
	* gimple.h (enum gimple_debug_subcode): Add
	GIMPLE_DEBUG_INLINE_ENTRY.
	(gimple_build_debug_inline_entry): Declare.
	(gimple_debug_inline_entry_p): New.
	(gimple_debug_nonbind_marker_p): Adjust.
	* insn-notes.def (INLINE_ENTRY): New.
	* print-rtl.c (rtx_writer::print_rtx_operand_code_0): Handle
	inline entry marker notes.
	(print_insn): Likewise.
	* rtl.h	(NOTE_MARKER_P): Add INLINE_ENTRY support.
	(INSN_DEBUG_MARKER_KIND): Likewise.
	(GEN_RTX_DEBUG_MARKER_INLINE_ENTRY_PAT): New.
	* tree-inline.c	(expand_call_inline): Build and insert
	debug_inline_entry stmt.
	* tree-ssa-live.c (remove_unused_scope_block_p): Preserve
	inline entry blocks early, if nonbind markers are enabled.
	(dump_scope_block): Dump fragment info.
	* var-tracking.c (reemit_marker_as_note): Handle inline entry note.
	* doc/gimple.texi (gimple_debug_inline_entry_p): New.
	(gimple_build_debug_inline_entry): New.
	* doc/invoke.texi (gstatement-frontiers, gno-statement-frontiers):
	Enable/disable inline entry points too.
	* doc/rtl.texi (NOTE_INSN_INLINE_ENTRY): New.
	(DEBUG_INSN): Describe inline entry markers.

From-SVN: r257511

This patch introduces an option to enable the generation of location
views along with location lists.  The exact format depends on the
DWARF version: it can be a separate attribute (DW_AT_GNU_locviews) or
(DW_LLE_view_pair) entries in DWARF5+ loclists.

Line number tables are also affected.  If the assembler is found, at
compiler build time, to support .loc views, we use them and
assembler-computed view labels, otherwise we output compiler-generated
line number programs with conservatively-computed view labels.  In
either case, we output view information next to line number changes
when verbose assembly output is requested.

This patch requires an LVU patch that modifies the exported API of
final_scan_insn.  It also expects the entire SFN patchset to be
installed first, although SFN is not a requirement for LVU.

for  include/ChangeLog

	* dwarf2.def (DW_AT_GNU_locviews): New.
	* dwarf2.h (enum dwarf_location_list_entry_type): Add
	DW_LLE_GNU_view_pair.
	(DW_LLE_view_pair): Define.

for  gcc/ChangeLog

	* common.opt (gvariable-location-views): New.
	(gvariable-location-views=incompat5): New.
	* config.in: Rebuilt.
	* configure: Rebuilt.
	* configure.ac: Test assembler for view support.
	* dwarf2asm.c (dw2_asm_output_symname_uleb128): New.
	* dwarf2asm.h (dw2_asm_output_symname_uleb128): Declare.
	* dwarf2out.c (var_loc_view): New typedef.
	(struct dw_loc_list_struct): Add vl_symbol, vbegin, vend.
	(dwarf2out_locviews_in_attribute): New.
	(dwarf2out_locviews_in_loclist): New.
	(dw_val_equal_p): Compare val_view_list of dw_val_class_view_lists.
	(enum dw_line_info_opcode): Add LI_adv_address.
	(struct dw_line_info_table): Add view.
	(RESET_NEXT_VIEW, RESETTING_VIEW_P): New macros.
	(DWARF2_ASM_VIEW_DEBUG_INFO): Define default.
	(zero_view_p): New variable.
	(ZERO_VIEW_P): New macro.
	(output_asm_line_debug_info): New.
	(struct var_loc_node): Add view.
	(add_AT_view_list, AT_loc_list): New.
	(add_var_loc_to_decl): Add view param.  Test it against last.
	(new_loc_list): Add view params.  Record them.
	(AT_loc_list_ptr): Handle loc and view lists.
	(view_list_to_loc_list_val_node): New.
	(print_dw_val): Handle dw_val_class_view_list.
	(size_of_die): Likewise.
	(value_format): Likewise.
	(loc_list_has_views): New.
	(gen_llsym): Set vl_symbol too.
	(maybe_gen_llsym, skip_loc_list_entry): New.
	(dwarf2out_maybe_output_loclist_view_pair): New.
	(output_loc_list): Output view list or entries too.
	(output_view_list_offset): New.
	(output_die): Handle dw_val_class_view_list.
	(output_dwarf_version): New.
	(output_compilation_unit_header): Use it.
	(output_skeleton_debug_sections): Likewise.
	(output_rnglists, output_line_info): Likewise.
	(output_pubnames, output_aranges): Update version comments.
	(output_one_line_info_table): Output view numbers in asm comments.
	(dw_loc_list): Determine current endview, pass it to new_loc_list.
	Call maybe_gen_llsym.
	(loc_list_from_tree_1): Adjust.
	(add_AT_location_description): Create view list attribute if
	needed, check it's absent otherwise.
	(convert_cfa_to_fb_loc_list): Adjust.
	(maybe_emit_file): Call output_asm_line_debug_info for test.
	(dwarf2out_var_location): Reset views as needed.  Precompute
	add_var_loc_to_decl args.  Call get_attr_min_length only if we have the
	attribute.  Set view.
	(new_line_info_table): Reset next view.
	(set_cur_line_info_table): Call output_asm_line_debug_info for test.
	(dwarf2out_source_line): Likewise.  Output view resets and labels to
	the assembler, or select appropriate line info opcodes.
	(prune_unused_types_walk_attribs): Handle dw_val_class_view_list.
	(optimize_string_length): Catch it.  Adjust.
	(resolve_addr): Copy vl_symbol along with ll_symbol.  Handle
	dw_val_class_view_list, and remove it if no longer needed.
	(hash_loc_list): Hash view numbers.
	(loc_list_hasher::equal): Compare them.
	(optimize_location_lists): Check whether a view list symbol is
	needed, and whether the locview attribute is present, and
	whether they match.  Remove the locview attribute if no longer
	needed.
	(index_location_lists): Call skip_loc_list_entry for test.
	(dwarf2out_finish): Call output_asm_line_debug_info for test.
	Use output_dwarf_version.
	* dwarf2out.h (enum dw_val_class): Add dw_val_class_view_list.
	(struct dw_val_node): Add val_view_list.
	* final.c (SEEN_NEXT_VIEW): New.
	(set_next_view_needed): New.
	(clear_next_view_needed): New.
	(maybe_output_next_view): New.
	(final_start_function): Rename to...
	(final_start_function_1): ... this.  Take pointer to FIRST,
	add SEEN parameter.  Emit param bindings in the initial view.
	(final_start_function): Reintroduce SEEN-less interface.
	(final): Rename to...
	(final_1): ... this.  Take SEEN parameter.  Output final pending
	next view at the end.
	(final): Reintroduce seen-less interface.
	(final_scan_insn): Output pending next view before switching
	sections or ending a block.  Mark the next view as needed when
	outputting variable locations.  Notify debug backend of section
	changes, and of location view changes.
	(rest_of_handle_final): Adjust.
	* toplev.c (process_options): Autodetect value for debug variable
	location views option.  Warn on incompat5 without -gdwarf-5.
	* doc/invoke.texi (gvariable-location-views): New.
	(gvariable-location-views=incompat5): New.
	(gno-variable-location-views): New.

From-SVN: r257510

PR 84136 reports an ICE within sccvn_dom_walker when handling a
C/C++ source file that overuses the labels-as-values extension.
The code in question stores a jump label into a global, and then
jumps to it from another function, which ICEs after inlining:

void* a;

void foo() {
  if ((a = &&l))
      return;

  l:;
}

int main() {
  foo();
  goto *a;

  return 0;
}

This appears to be far beyond what we claim to support in this
extension - but we shouldn't ICE.

What's happening is that, after inlining, we have usage of a *copy*
of the label, which optimizes away the if-return logic, turning it
into an infinite loop.

On entry to the sccvn_dom_walker we have this gimple:

main ()
{
  void * a.0_1;

  <bb 2> [count: 0]:
  a = &l;

  <bb 3> [count: 0]:
l:
  a.0_1 = a;
  goto a.0_1;
}

and:
  edge taken = find_taken_edge (bb, vn_valueize (val));
reasonably valueizes the:
  goto a.0_1;
after the:
  a = &l;
  a.0_1 = a;
as if it were:
  goto *&l;

find_taken_edge_computed_goto then has:

2380	  dest = label_to_block (val);
2381	  if (dest)
2382	    {
2383	      e = find_edge (bb, dest);
2384	      gcc_assert (e != NULL);
2385	    }

which locates dest as a self-jump from block 3 back to itself.

However, the find_edge call returns NULL - it has a predecessor edge
from block 2, but no successor edges.

Hence the assertion fails and we ICE.

A successor edge from the computed goto could have been created by
make_edges if the label stmt had been in the function, but make_edges
only looks in the current function when handling computed gotos, and
the label only appeared after inlining.

The following patch removes the assertion, fixing the ICE.

gcc/testsuite/ChangeLog:
	PR tree-optimization/84136
	* gcc.c-torture/compile/pr84136.c: New test.

gcc/ChangeLog:
	PR tree-optimization/84136
	* tree-cfg.c (find_taken_edge_computed_goto): Remove assertion
	that the result of find_edge is non-NULL.

From-SVN: r257509

From-SVN: r257508

re PR target/83008 ([performance] Is it better to avoid extra instructions in data passing between loops?)

	PR target/83008
	* config/i386/x86-tune-costs.h (skylake_cost): Fix cost of
	storing integer register in SImode.  Fix cost of 256 and 512
	byte aligned SSE register store.

	* config/i386/i386.c (ix86_multiplication_cost): Fix
	multiplication cost for TARGET_AVX512DQ.

testsuite/ChangeLog:	

	PR target/83008
	* gcc.target/i386/pr83008.c: New test.

From-SVN: r257505

	PR target/81143
	* gcc.target/powerpc/pr79799-2.c: Use __LITTLE_ENDIAN__.

From-SVN: r257504

2018-02-08  Paolo Carlini  <paolo.carlini@oracle.com>

	* constexpr.c (cxx_eval_component_reference): Use INDIRECT_REF_P.
	* lambda.c (build_capture_proxy): Likewise.
	* search.c (field_access_p): Likewise.
	* semantics.c (omp_clause_decl, omp_privatize_field,
	finish_omp_clauses): Likewise.

From-SVN: r257503

/cp
2018-02-08  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/83806
	* typeck.c (decay_conversion): Use mark_rvalue_use for the special
	case of nullptr too.

/testsuite
2018-02-08  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/83806
	* g++.dg/warn/Wunused-parm-11.C: New.

From-SVN: r257502

PR target/84113

From-SVN: r257500

re PR tree-optimization/84238 (ICE tree check: expected integer_cst, have plus_expr in to_wide, at tree.h:5527)

	PR tree-optimization/84238
	* tree-ssa-strlen.c (maybe_diag_stxncpy_trunc): Verify the result of
	get_range_strlen.

	* gcc.dg/Wstringop-overflow-3.c: New test.

From-SVN: r257497

https://gcc.gnu.org/ml/gcc-patches/2018-02/msg00434.html
	* class.c (finish_struct): Fix std:initializer_list diagnostic
	formatting.

	* g++.dg/cpp0x/initlist93.C: Adjust diagnostic.

From-SVN: r257496

    
    If we trace back through code that has no debug info, as when calling
    through C code compiled with -g0, we won't have a function name.
    Try to fetch the function name using the symbol table.
    
    Adding the test case revealed that gotest failed to use the gccgo tag
    when matching files, so add that.
    
    Reviewed-on: https://go-review.googlesource.com/92756

From-SVN: r257495

Makefile.am (check-gccgo, check-gcc): Add options to pick up target libstdc++, to permit tests that use C++.

	* Makefile.am (check-gccgo, check-gcc): Add options to pick up
	target libstdc++, to permit tests that use C++.
	* Makefile.in: Rebuild.

From-SVN: r257494

    
    Reviewed-on: https://go-review.googlesource.com/92736

From-SVN: r257493

PR83753 was about a case in which we ended up trying to "vectorise"
a group of loads ore stores using single-element vectors.  The problem
was that we were classifying the load or store as VMAT_CONTIGUOUS_PERMUTE
rather than VMAT_CONTIGUOUS, even though it doesn't make sense to permute
a single-element vector.

In that PR it was enough to change get_group_load_store_type,
because vectorisation ended up being unprofitable and so we didn't
take things further.  But when vectorisation is profitable, the same
fix is needed in vectorizable_load and vectorizable_store.

2018-02-08  Richard Sandiford  <richard.sandiford@linaro.org>

gcc/
	PR tree-optimization/84265
	* tree-vect-stmts.c (vectorizable_store): Don't treat
	VMAT_CONTIGUOUS accesses as grouped.
	(vectorizable_load): Likewise.

gcc/testsuite/
	PR tree-optimization/84265
	* gcc.dg/vect/pr84265.c: New test.

From-SVN: r257492

This patch is part 2 of the fix for PR 81635.  It means that
split_constant_offset can handle loops like:

  for (unsigned int i = 0; i < n; i += 4)
    {
      a[i] = ...;
      a[i + 1] = ...;
    }

CCP records that "i" must have its low 2 bits clear, but we don't
include this information in the range of "i", which remains [0, +INF].
I tried making set_nonzero_bits update the range info in the same
way that set_range_info updates the nonzero bits, but it regressed
cases like vrp117.c and made some other tests worse.

vrp117.c has a multiplication by 10, so CCP can infer that the low bit
of the result is clear.  If we included that in the range, the range
would go from [-INF, +INF] to [-INF, not-quite-+INF].  However,
the multiplication is also known to overflow in all cases, so VRP
saturates the result to [INT_MAX, INT_MAX].  This obviously creates a
contradiction with the nonzero bits, and intersecting the new saturated
range with an existing not-quite-+INF range would make us drop to
VR_UNDEFINED.  We're prepared to fold a comparison with an [INT_MAX,
INT_MAX] value but not with a VR_UNDEFINED value.

The other problems were created when intersecting [-INF, not-quite-+INF]
with a useful VR_ANTI_RANGE like ~[-1, 1].  The intersection would
keep the former range rather than the latter.

The patch therefore keeps the adjustment local to split_constant_offset
for now, but adds a helper routine so that it's easy to move this later.

2018-02-08  Richard Sandiford  <richard.sandiford@linaro.org>

gcc/
	PR tree-optimization/81635
	* wide-int.h (wi::round_down_for_mask, wi::round_up_for_mask): Declare.
	* wide-int.cc (wi::round_down_for_mask, wi::round_up_for_mask)
	(test_round_for_mask): New functions.
	(wide_int_cc_tests): Call test_round_for_mask.
	* tree-vrp.h (intersect_range_with_nonzero_bits): Declare.
	* tree-vrp.c (intersect_range_with_nonzero_bits): New function.
	* tree-data-ref.c (split_constant_offset_1): Use it to refine the
	range returned by get_range_info.

gcc/testsuite/
	PR tree-optimization/81635
	* gcc.dg/vect/bb-slp-pr81635-3.c: New test.
	* gcc.dg/vect/bb-slp-pr81635-4.c: Likewise.

From-SVN: r257491

	PR ipa/81360
	* cgraph.h (symtab_node::output_to_lto_symbol_table_p): Declare
	* symtab.c: Include builtins.h
	(symtab_node::output_to_lto_symbol_table_p): Move here
	from lto-streamer-out.c:output_symbol_p.
	* lto-streamer-out.c (write_symbol): Turn early exit to assert.
	(output_symbol_p): Move all logic to symtab.c
	(produce_symtab): Update.

	* lto.c (unify_scc): Register prevailing trees, not trees to be freed.
	(read_cgraph_and_symbols): Use
	symtab_node::output_to_lto_symbol_table_p.

From-SVN: r257490

This patch implements GCC support for mitigating vulnerability
CVE-2017-5715 known as Spectre #2 on IBM Z.

In order to disable prediction of indirect branches the implementation
makes use of an IBM Z specific feature - the execute instruction.
Performing an indirect branch via execute prevents the branch from
being subject to dynamic branch prediction.

The implementation tries to stay close to the x86 solution regarding
user interface.

x86 style options supported (without thunk-inline):

-mindirect-branch=(keep|thunk|thunk-extern)
-mfunction-return=(keep|thunk|thunk-extern)

IBM Z specific options:

-mindirect-branch-jump=(keep|thunk|thunk-extern|thunk-inline)
-mindirect-branch-call=(keep|thunk|thunk-extern)
-mfunction-return-reg=(keep|thunk|thunk-extern)
-mfunction-return-mem=(keep|thunk|thunk-extern)

These options allow us to enable/disable the branch conversion at a
finer granularity.

-mindirect-branch sets the value of -mindirect-branch-jump and
 -mindirect-branch-call.

-mfunction-return sets the value of -mfunction-return-reg and
 -mfunction-return-mem.

All these options are supported on GCC command line as well as
function attributes.

'thunk' triggers the generation of out of line thunks (expolines) and
replaces the formerly indirect branch with a direct branch to the
thunk.  Depending on the -march= setting two different types of thunks
are generated.  With -march=z10 or higher exrl (execute relative long)
is being used while targeting older machines makes use of larl/ex
instead.  From a security perspective the exrl variant is preferable.

'thunk-extern' does the branch replacement like 'thunk' but does not
emit the thunks.

'thunk-inline' is only available for indirect jumps.  It should be used
in environments where correct CFI is important - known as user space.

Additionally the patch introduces the -mindirect-branch-table option
which generates tables pointing to the locations which have been
modified.  This is supposed to allow reverting the changes without
re-compilation in situations where it isn't required. The sections are
split up into one section per option.

gcc/ChangeLog:

2018-02-08  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>

	* config/s390/s390-opts.h (enum indirect_branch): Define.
	* config/s390/s390-protos.h (s390_return_addr_from_memory)
	(s390_indirect_branch_via_thunk)
	(s390_indirect_branch_via_inline_thunk): Add function prototypes.
	(enum s390_indirect_branch_type): Define.
	* config/s390/s390.c (struct s390_frame_layout, struct
	machine_function): Remove.
	(indirect_branch_prez10thunk_mask, indirect_branch_z10thunk_mask)
	(indirect_branch_table_label_no, indirect_branch_table_name):
	Define variables.
	(INDIRECT_BRANCH_NUM_OPTIONS): Define macro.
	(enum s390_indirect_branch_option): Define.
	(s390_return_addr_from_memory): New function.
	(s390_handle_string_attribute): New function.
	(s390_attribute_table): Add new attribute handler.
	(s390_execute_label): Handle UNSPEC_EXECUTE_JUMP patterns.
	(s390_indirect_branch_via_thunk): New function.
	(s390_indirect_branch_via_inline_thunk): New function.
	(s390_function_ok_for_sibcall): When jumping via thunk disallow
	sibling call optimization for non z10 compiles.
	(s390_emit_call): Force indirect branch target to be a single
	register.  Add r1 clobber for non-z10 compiles.
	(s390_emit_epilogue): Emit return jump via return_use expander.
	(s390_reorg): Handle JUMP_INSNs as execute targets.
	(s390_option_override_internal): Perform validity checks for the
	new command line options.
	(s390_indirect_branch_attrvalue): New function.
	(s390_indirect_branch_settings): New function.
	(s390_set_current_function): Invoke s390_indirect_branch_settings.
	(s390_output_indirect_thunk_function):  New function.
	(s390_code_end): Implement target hook.
	(s390_case_values_threshold): Implement target hook.
	(TARGET_ASM_CODE_END, TARGET_CASE_VALUES_THRESHOLD): Define target
	macros.
	* config/s390/s390.h (struct s390_frame_layout)
	(struct	machine_function): Move here from s390.c.
	(TARGET_INDIRECT_BRANCH_NOBP_RET)
	(TARGET_INDIRECT_BRANCH_NOBP_JUMP)
	(TARGET_INDIRECT_BRANCH_NOBP_JUMP_THUNK)
	(TARGET_INDIRECT_BRANCH_NOBP_JUMP_INLINE_THUNK)
	(TARGET_INDIRECT_BRANCH_NOBP_CALL)
	(TARGET_DEFAULT_INDIRECT_BRANCH_TABLE)
	(TARGET_INDIRECT_BRANCH_THUNK_NAME_EXRL)
	(TARGET_INDIRECT_BRANCH_THUNK_NAME_EX)
	(TARGET_INDIRECT_BRANCH_TABLE): Define macros.
	* config/s390/s390.md (UNSPEC_EXECUTE_JUMP)
	(INDIRECT_BRANCH_THUNK_REGNUM): Define constants.
	(mnemonic attribute): Add values which aren't recognized
	automatically.
	("*cjump_long", "*icjump_long", "*basr", "*basr_r"): Disable
	pattern for branch conversion.  Fix mnemonic attribute.
	("*c<code>", "*sibcall_br", "*sibcall_value_br", "*return"): Emit
	indirect branch via thunk if requested.
	("indirect_jump", "<code>"): Expand patterns for branch conversion.
	("*indirect_jump"): Disable for branch conversion using out of
	line thunks.
	("indirect_jump_via_thunk<mode>_z10")
	("indirect_jump_via_thunk<mode>")
	("indirect_jump_via_inlinethunk<mode>_z10")
	("indirect_jump_via_inlinethunk<mode>", "*casesi_jump")
	("casesi_jump_via_thunk<mode>_z10", "casesi_jump_via_thunk<mode>")
	("casesi_jump_via_inlinethunk<mode>_z10")
	("casesi_jump_via_inlinethunk<mode>", "*basr_via_thunk<mode>_z10")
	("*basr_via_thunk<mode>", "*basr_r_via_thunk_z10")
	("*basr_r_via_thunk", "return<mode>_prez10"): New pattern.
	("*indirect2_jump"): Disable for branch conversion.
	("casesi_jump"): Turn into expander and expand patterns for branch
	conversion.
	("return_use"): New expander.
	("*return"): Emit return via thunk and rename it to ...
	("*return<mode>"): ... this one.
	* config/s390/s390.opt: Add new options and and enum for the
	option values.

gcc/testsuite/ChangeLog:

2018-02-08  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>

	* gcc.target/s390/nobp-function-pointer-attr.c: New test.
	* gcc.target/s390/nobp-function-pointer-nothunk.c: New test.
	* gcc.target/s390/nobp-function-pointer-z10.c: New test.
	* gcc.target/s390/nobp-function-pointer-z900.c: New test.
	* gcc.target/s390/nobp-indirect-jump-attr.c: New test.
	* gcc.target/s390/nobp-indirect-jump-inline-attr.c: New test.
	* gcc.target/s390/nobp-indirect-jump-inline-z10.c: New test.
	* gcc.target/s390/nobp-indirect-jump-inline-z900.c: New test.
	* gcc.target/s390/nobp-indirect-jump-nothunk.c: New test.
	* gcc.target/s390/nobp-indirect-jump-z10.c: New test.
	* gcc.target/s390/nobp-indirect-jump-z900.c: New test.
	* gcc.target/s390/nobp-return-attr-all.c: New test.
	* gcc.target/s390/nobp-return-attr-neg.c: New test.
	* gcc.target/s390/nobp-return-mem-attr.c: New test.
	* gcc.target/s390/nobp-return-mem-nothunk.c: New test.
	* gcc.target/s390/nobp-return-mem-z10.c: New test.
	* gcc.target/s390/nobp-return-mem-z900.c: New test.
	* gcc.target/s390/nobp-return-reg-attr.c: New test.
	* gcc.target/s390/nobp-return-reg-mixed.c: New test.
	* gcc.target/s390/nobp-return-reg-nothunk.c: New test.
	* gcc.target/s390/nobp-return-reg-z10.c: New test.
	* gcc.target/s390/nobp-return-reg-z900.c: New test.
	* gcc.target/s390/nobp-table-jump-inline-z10.c: New test.
	* gcc.target/s390/nobp-table-jump-inline-z900.c: New test.
	* gcc.target/s390/nobp-table-jump-z10.c: New test.
	* gcc.target/s390/nobp-table-jump-z900.c: New test.

From-SVN: r257489