The symbols for the functions supporting heap-based trampolines were
exported at an incorrect symbol version, the following patch fixes that.
As requested in the PR, this also renames __builtin_nested_func_ptr* to
__gcc_nested_func_ptr*. In carrying our the rename, we move the builtins
to use DEF_EXT_LIB_BUILTIN.
PR libgcc/113402
gcc/ChangeLog:
* builtins.cc (expand_builtin): Handle BUILT_IN_GCC_NESTED_PTR_CREATED
and BUILT_IN_GCC_NESTED_PTR_DELETED.
* builtins.def (BUILT_IN_GCC_NESTED_PTR_CREATED,
BUILT_IN_GCC_NESTED_PTR_DELETED): Make these builtins LIB-EXT and
rename the library fallbacks to __gcc_nested_func_ptr_created and
__gcc_nested_func_ptr_deleted.
* doc/invoke.texi: Rename these to __gcc_nested_func_ptr_created
and __gcc_nested_func_ptr_deleted.
* tree-nested.cc (finalize_nesting_tree_1): Use builtin_explicit for
BUILT_IN_GCC_NESTED_PTR_CREATED and BUILT_IN_GCC_NESTED_PTR_DELETED.
* tree.cc (build_common_builtin_nodes): Build the
BUILT_IN_GCC_NESTED_PTR_CREATED and BUILT_IN_GCC_NESTED_PTR_DELETED local
builtins only for non-explicit.
libgcc/ChangeLog:
* config/aarch64/heap-trampoline.c: Rename
__builtin_nested_func_ptr_created to __gcc_nested_func_ptr_created and
__builtin_nested_func_ptr_deleted to __gcc_nested_func_ptr_deleted.
* config/i386/heap-trampoline.c: Likewise.
* libgcc2.h: Likewise.
* libgcc-std.ver.in (GCC_7.0.0): Likewise and then move
__gcc_nested_func_ptr_created and
__gcc_nested_func_ptr_deleted from this symbol version to ...
(GCC_14.0.0): ... this one.
Signed-off-by: Iain Sandoe <iain@sandoe.co.uk>
Co-authored-by: Jakub Jelinek <jakub@redhat.com>
This patch adds the strub attribute for function and variable types,
command-line options, passes and adjustments to implement it,
documentation, and tests.
Stack scrubbing is implemented in a machine-independent way: functions
with strub enabled are modified so that they take an extra stack
watermark argument, that they update with their stack use, and the
caller can then zero it out once it regains control, whether by return
or exception. There are two ways to go about it: at-calls, that
modifies the visible interface (signature) of the function, and
internal, in which the body is moved to a clone, the clone undergoes
the interface change, and the function becomes a wrapper, preserving
its original interface, that calls the clone and then clears the stack
used by it.
Variables can also be annotated with the strub attribute, so that
functions that read from them get stack scrubbing enabled implicitly,
whether at-calls, for functions only usable within a translation unit,
or internal, for functions whose interfaces must not be modified.
There is a strict mode, in which functions that have their stack
scrubbed can only call other functions with stack-scrubbing
interfaces, or those explicitly marked as callable from strub
contexts, so that an entire call chain gets scrubbing, at once or
piecemeal depending on optimization levels. In the default mode,
relaxed, this requirement is not enforced by the compiler.
The implementation adds two IPA passes, one that assigns strub modes
early on, another that modifies interfaces and adds calls to the
builtins that jointly implement stack scrubbing. Another builtin,
that obtains the stack pointer, is added for use in the implementation
of the builtins, whether expanded inline or called in libgcc.
There are new command-line options to change operation modes and to
force the feature disabled; it is enabled by default, but it has no
effect and is implicitly disabled if the strub attribute is never
used. There are also options meant to use for testing the feature,
enabling different strubbing modes for all (viable) functions.
for gcc/ChangeLog
* Makefile.in (OBJS): Add ipa-strub.o.
(GTFILES): Add ipa-strub.cc.
* builtins.def (BUILT_IN_STACK_ADDRESS): New.
(BUILT_IN___STRUB_ENTER): New.
(BUILT_IN___STRUB_UPDATE): New.
(BUILT_IN___STRUB_LEAVE): New.
* builtins.cc: Include ipa-strub.h.
(STACK_STOPS, STACK_UNSIGNED): Define.
(expand_builtin_stack_address): New.
(expand_builtin_strub_enter): New.
(expand_builtin_strub_update): New.
(expand_builtin_strub_leave): New.
(expand_builtin): Call them.
* common.opt (fstrub=*): New options.
* doc/extend.texi (strub): New type attribute.
(__builtin_stack_address): New function.
(Stack Scrubbing): New section.
* doc/invoke.texi (-fstrub=*): New options.
(-fdump-ipa-*): New passes.
* gengtype-lex.l: Ignore multi-line pp-directives.
* ipa-inline.cc: Include ipa-strub.h.
(can_inline_edge_p): Test strub_inlinable_to_p.
* ipa-split.cc: Include ipa-strub.h.
(execute_split_functions): Test strub_splittable_p.
* ipa-strub.cc, ipa-strub.h: New.
* passes.def: Add strub_mode and strub passes.
* tree-cfg.cc (gimple_verify_flow_info): Note on debug stmts.
* tree-pass.h (make_pass_ipa_strub_mode): Declare.
(make_pass_ipa_strub): Declare.
(make_pass_ipa_function_and_variable_visibility): Fix
formatting.
* tree-ssa-ccp.cc (optimize_stack_restore): Keep restores
before strub leave.
* attribs.cc: Include ipa-strub.h.
(decl_attributes): Support applying attributes to function
type, rather than pointer type, at handler's request.
(comp_type_attributes): Combine strub_comptypes and target
comp_type results.
* doc/tm.texi.in (TARGET_STRUB_USE_DYNAMIC_ARRAY): New.
(TARGET_STRUB_MAY_USE_MEMSET): New.
* doc/tm.texi: Rebuilt.
* cgraph.h (symtab_node::reset): Add preserve_comdat_group
param, with a default.
* cgraphunit.cc (symtab_node::reset): Use it.
for gcc/c-family/ChangeLog
* c-attribs.cc: Include ipa-strub.h.
(handle_strub_attribute): New.
(c_common_attribute_table): Add strub.
for gcc/ada/ChangeLog
* gcc-interface/trans.cc: Include ipa-strub.h.
(gigi): Make internal decls for targets of compiler-generated
calls strub-callable too.
(build_raise_check): Likewise.
* gcc-interface/utils.cc: Include ipa-strub.h.
(handle_strub_attribute): New.
(gnat_internal_attribute_table): Add strub.
for gcc/testsuite/ChangeLog
* c-c++-common/strub-O0.c: New.
* c-c++-common/strub-O1.c: New.
* c-c++-common/strub-O2.c: New.
* c-c++-common/strub-O2fni.c: New.
* c-c++-common/strub-O3.c: New.
* c-c++-common/strub-O3fni.c: New.
* c-c++-common/strub-Og.c: New.
* c-c++-common/strub-Os.c: New.
* c-c++-common/strub-all1.c: New.
* c-c++-common/strub-all2.c: New.
* c-c++-common/strub-apply1.c: New.
* c-c++-common/strub-apply2.c: New.
* c-c++-common/strub-apply3.c: New.
* c-c++-common/strub-apply4.c: New.
* c-c++-common/strub-at-calls1.c: New.
* c-c++-common/strub-at-calls2.c: New.
* c-c++-common/strub-defer-O1.c: New.
* c-c++-common/strub-defer-O2.c: New.
* c-c++-common/strub-defer-O3.c: New.
* c-c++-common/strub-defer-Os.c: New.
* c-c++-common/strub-internal1.c: New.
* c-c++-common/strub-internal2.c: New.
* c-c++-common/strub-parms1.c: New.
* c-c++-common/strub-parms2.c: New.
* c-c++-common/strub-parms3.c: New.
* c-c++-common/strub-relaxed1.c: New.
* c-c++-common/strub-relaxed2.c: New.
* c-c++-common/strub-short-O0-exc.c: New.
* c-c++-common/strub-short-O0.c: New.
* c-c++-common/strub-short-O1.c: New.
* c-c++-common/strub-short-O2.c: New.
* c-c++-common/strub-short-O3.c: New.
* c-c++-common/strub-short-Os.c: New.
* c-c++-common/strub-strict1.c: New.
* c-c++-common/strub-strict2.c: New.
* c-c++-common/strub-tail-O1.c: New.
* c-c++-common/strub-tail-O2.c: New.
* c-c++-common/torture/strub-callable1.c: New.
* c-c++-common/torture/strub-callable2.c: New.
* c-c++-common/torture/strub-const1.c: New.
* c-c++-common/torture/strub-const2.c: New.
* c-c++-common/torture/strub-const3.c: New.
* c-c++-common/torture/strub-const4.c: New.
* c-c++-common/torture/strub-data1.c: New.
* c-c++-common/torture/strub-data2.c: New.
* c-c++-common/torture/strub-data3.c: New.
* c-c++-common/torture/strub-data4.c: New.
* c-c++-common/torture/strub-data5.c: New.
* c-c++-common/torture/strub-indcall1.c: New.
* c-c++-common/torture/strub-indcall2.c: New.
* c-c++-common/torture/strub-indcall3.c: New.
* c-c++-common/torture/strub-inlinable1.c: New.
* c-c++-common/torture/strub-inlinable2.c: New.
* c-c++-common/torture/strub-ptrfn1.c: New.
* c-c++-common/torture/strub-ptrfn2.c: New.
* c-c++-common/torture/strub-ptrfn3.c: New.
* c-c++-common/torture/strub-ptrfn4.c: New.
* c-c++-common/torture/strub-pure1.c: New.
* c-c++-common/torture/strub-pure2.c: New.
* c-c++-common/torture/strub-pure3.c: New.
* c-c++-common/torture/strub-pure4.c: New.
* c-c++-common/torture/strub-run1.c: New.
* c-c++-common/torture/strub-run2.c: New.
* c-c++-common/torture/strub-run3.c: New.
* c-c++-common/torture/strub-run4.c: New.
* c-c++-common/torture/strub-run4c.c: New.
* c-c++-common/torture/strub-run4d.c: New.
* c-c++-common/torture/strub-run4i.c: New.
* g++.dg/strub-run1.C: New.
* g++.dg/torture/strub-init1.C: New.
* g++.dg/torture/strub-init2.C: New.
* g++.dg/torture/strub-init3.C: New.
* gnat.dg/strub_attr.adb, gnat.dg/strub_attr.ads: New.
* gnat.dg/strub_ind.adb, gnat.dg/strub_ind.ads: New.
for libgcc/ChangeLog
* Makefile.in (LIB2ADD): Add strub.c.
* libgcc2.h (__strub_enter, __strub_update, __strub_leave):
Declare.
* strub.c: New.
* libgcc-std.ver.in (__strub_enter): Add to GCC_14.0.0.
(__strub_update, __strub_leave): Likewise.
The libgcc-exported runtime component of control flow redundancy
hardening was missing symbol versioning information. Add it.
for libgcc/ChangeLog
* libgcc-std.ver.in (__hardcfr_check): Add to GCC_14.0.0.
This patch adds the library helpers for multiplication, division + modulo
and casts from and to floating point (both binary and decimal).
As described in the intro, the first step is try to reduce further the
passed in precision by skipping over most significant limbs with just zeros
or sign bit copies. For multiplication and division I've implemented
a simple algorithm, using something smarter like Karatsuba or Toom N-Way
might be faster for very large _BitInts (which we don't support right now
anyway), but could mean more code in libgcc, which maybe isn't what people
are willing to accept.
For the to/from floating point conversions the patch uses soft-fp, because
it already has tons of handy macros which can be used for that. In theory
it could be implemented using {,unsigned} long long or {,unsigned} __int128
to/from floating point conversions with some frexp before/after, but at that
point we already need to force it into integer registers and analyze it
anyway. Plus, for 32-bit arches there is no __int128 that could be used
for XF/TF mode stuff.
I know that soft-fp is owned by glibc and I think the op-common.h change
should be propagated there, but the bitint stuff is really GCC specific
and IMHO doesn't belong into the glibc copy.
2023-09-06 Jakub Jelinek <jakub@redhat.com>
PR c/102989
libgcc/
* config/aarch64/t-softfp (softfp_extras): Use += rather than :=.
* config/i386/64/t-softfp (softfp_extras): Likewise.
* config/i386/libgcc-glibc.ver (GCC_14.0.0): Export _BitInt support
routines.
* config/i386/t-softfp (softfp_extras): Add fixxfbitint and
bf, hf and xf mode floatbitint.
(CFLAGS-floatbitintbf.c, CFLAGS-floatbitinthf.c): Add -msse2.
* config/riscv/t-softfp32 (softfp_extras): Use += rather than :=.
* config/rs6000/t-e500v1-fp (softfp_extras): Likewise.
* config/rs6000/t-e500v2-fp (softfp_extras): Likewise.
* config/t-softfp (softfp_floatbitint_funcs): New.
(softfp_bid_list): New.
(softfp_func_list): Add sf and df mode from and to _BitInt libcalls.
(softfp_bid_file_list): New.
(LIB2ADD_ST): Add $(softfp_bid_file_list).
* config/t-softfp-sfdftf (softfp_extras): Add fixtfbitint and
floatbitinttf.
* config/t-softfp-tf (softfp_extras): Likewise.
* libgcc2.c (bitint_reduce_prec): New inline function.
(BITINT_INC, BITINT_END): Define.
(bitint_mul_1, bitint_addmul_1): New helper functions.
(__mulbitint3): New function.
(bitint_negate, bitint_submul_1): New helper functions.
(__divmodbitint4): New function.
* libgcc2.h (LIBGCC2_UNITS_PER_WORD): When building _BitInt support
libcalls, redefine depending on __LIBGCC_BITINT_LIMB_WIDTH__.
(__mulbitint3, __divmodbitint4): Declare.
* libgcc-std.ver.in (GCC_14.0.0): Export _BitInt support routines.
* Makefile.in (lib2funcs): Add _mulbitint3.
(LIB2_DIVMOD_FUNCS): Add _divmodbitint4.
* soft-fp/bitint.h: New file.
* soft-fp/fixdfbitint.c: New file.
* soft-fp/fixsfbitint.c: New file.
* soft-fp/fixtfbitint.c: New file.
* soft-fp/fixxfbitint.c: New file.
* soft-fp/floatbitintbf.c: New file.
* soft-fp/floatbitintdf.c: New file.
* soft-fp/floatbitinthf.c: New file.
* soft-fp/floatbitintsf.c: New file.
* soft-fp/floatbitinttf.c: New file.
* soft-fp/floatbitintxf.c: New file.
* soft-fp/op-common.h (_FP_FROM_INT): Add support for rsize up to
4 * _FP_W_TYPE_SIZE rather than just 2 * _FP_W_TYPE_SIZE.
* soft-fp/bitintpow10.c: New file.
* soft-fp/fixsdbitint.c: New file.
* soft-fp/fixddbitint.c: New file.
* soft-fp/fixtdbitint.c: New file.
* soft-fp/floatbitintsd.c: New file.
* soft-fp/floatbitintdd.c: New file.
* soft-fp/floatbitinttd.c: New file.
* generic-morestack.c (__splitstack_find): Check for NULL old
stack value.
(__splitstack_resetcontext): New function.
(__splitstack_releasecontext): New function.
* libgcc-std.ver.in: Add new functions to GCC_4.7.0.
From-SVN: r181771
libgcc/:
* generic-morestack.c: Include <string.h>.
(uintptr_type): Define.
(struct initial_sp): Add dont_block_signals field. Reduce size of
extra array by 1.
(allocate_segment): Set prev field to NULL. Don't set
__morestack_current_segment or __morestack_segments.
(__generic_morestack): Update current->prev and *pp after calling
allocate_segment.
(__morestack_block_signals): Don't do anything if
dont_block_signals is set.
(__morestack_unblock_signals): Likewise.
(__generic_findstack): Check for initial_sp == NULL. Add casts to
uintptr_type.
(__splitstack_block_signals): New function.
(enum __splitstack_content_offsets): Define.
(__splitstack_getcontext, __splitstack_setcontext): New functions.
(__splitstack_makecontext): New function.
(__splitstack_block_signals_context): New function.
(__splitstack_find_context): New function.
* config/i386/morestack.S (__morestack_get_guard): New function.
(__morestack_set_guard, __morestack_make_guard): New functions.
* libgcc-std.ver.in: Add new functions to GCC_4.7.0.
gcc/testsuite/:
* lib/target-supports.exp (check_effective_target_ucontext_h): New
procedure.
* gcc.dg/split-5.c: New test.
From-SVN: r181234
libgcc/
* Makefile.in (LIBGCC_VER_FIXEDPOINT_GNU_PREFIX): New.
(libgcc-std.ver.in): Use above.
* fixed-bit.h (LIBGCC2_FIXEDBIT_GNU_PREFIX): Define, if
LIBGCC2_GNU_PREFIX is defined. Use instead of LIBGCC2_GNU_PREFIX
throughout file.
* config/t-fixedpoint-gnu-prefix: New file.
* config/t-gnu-prefix (LIBGCC_VER_FIXEDPOINT_GNU_PREFIX): Set.
* libgcc-std.ver.in (fixed-point routines): Use __FIXPTPFX__
instead of __PFX__.
From-SVN: r177019
