From d9c90c82d900fdae95df4499bf5f0a4ecb903b53 Mon Sep 17 00:00:00 2001 From: Thomas Schwinge Date: Tue, 28 May 2024 23:20:29 +0200 Subject: nvptx target: Global constructor, destructor support, via nvptx-tools 'ld' The function attributes 'constructor', 'destructor', and 'init_priority' now work, as do the C++ features making use of this. Test cases with effective target 'global_constructor' and 'init_priority' now generally work, and 'check-gcc-c++' test results greatly improve; no more "sorry, unimplemented: global constructors not supported on this target". For proper execution test results, this depends on "ld: Global constructor/destructor support". gcc/ * config/nvptx/nvptx.h: Configure global constructor, destructor support. gcc/testsuite/ * gcc.dg/no_profile_instrument_function-attr-1.c: GCC/nvptx is 'NO_DOT_IN_LABEL' but not 'NO_DOLLAR_IN_LABEL', so '$' may apper in identifiers. * lib/target-supports.exp (check_effective_target_global_constructor): Enable for nvptx. libgcc/ * config/nvptx/crt0.c (__gbl_ctors): New weak function. (__main): Invoke it. * config/nvptx/gbl-ctors.c: New. * config/nvptx/t-nvptx: Configure global constructor, destructor support. --- gcc/config/nvptx/nvptx.h | 14 +++- .../gcc.dg/no_profile_instrument_function-attr-1.c | 2 +- gcc/testsuite/lib/target-supports.exp | 3 +- libgcc/config/nvptx/crt0.c | 12 ++++ libgcc/config/nvptx/gbl-ctors.c | 74 ++++++++++++++++++++++ libgcc/config/nvptx/t-nvptx | 9 ++- 6 files changed, 109 insertions(+), 5 deletions(-) create mode 100644 libgcc/config/nvptx/gbl-ctors.c diff --git a/gcc/config/nvptx/nvptx.h b/gcc/config/nvptx/nvptx.h index e282aad..74f4a68 100644 --- a/gcc/config/nvptx/nvptx.h +++ b/gcc/config/nvptx/nvptx.h @@ -356,7 +356,19 @@ struct GTY(()) machine_function #define MOVE_MAX 8 #define MOVE_RATIO(SPEED) 4 #define FUNCTION_MODE QImode -#define HAS_INIT_SECTION 1 + +/* Implement global constructor, destructor support in a conceptually simpler + way than using 'collect2' (the program): implement the respective + functionality in the nvptx-tools 'ld'. This however still requires the + compiler-side effects corresponding to 'USE_COLLECT2': the global + constructor, destructor support functions need to have external linkage, and + therefore names that are "unique across the whole link". Use + '!targetm.have_ctors_dtors' to achieve this (..., and thus don't need to + provide 'targetm.asm_out.constructor', 'targetm.asm_out.destructor'). */ +#define TARGET_HAVE_CTORS_DTORS false + +/* See 'libgcc/config/nvptx/crt0.c' for wrapping of 'main'. */ +#define HAS_INIT_SECTION /* The C++ front end insists to link against libstdc++ -- which we don't build. Tell it to instead link against the innocuous libgcc. */ diff --git a/gcc/testsuite/gcc.dg/no_profile_instrument_function-attr-1.c b/gcc/testsuite/gcc.dg/no_profile_instrument_function-attr-1.c index 909f8a6..5b4101c 100644 --- a/gcc/testsuite/gcc.dg/no_profile_instrument_function-attr-1.c +++ b/gcc/testsuite/gcc.dg/no_profile_instrument_function-attr-1.c @@ -18,7 +18,7 @@ int main () return foo (); } -/* { dg-final { scan-tree-dump-times "__gcov0\[._\]main.* = PROF_edge_counter" 1 "optimized"} } */ +/* { dg-final { scan-tree-dump-times "__gcov0\[$._\]main.* = PROF_edge_counter" 1 "optimized"} } */ /* { dg-final { scan-tree-dump-times "__gcov_indirect_call_profiler_v" 1 "optimized" } } */ /* { dg-final { scan-tree-dump-times "__gcov_time_profiler_counter = " 1 "optimized" } } */ /* { dg-final { scan-tree-dump-times "__gcov_init" 1 "optimized" } } */ diff --git a/gcc/testsuite/lib/target-supports.exp b/gcc/testsuite/lib/target-supports.exp index f0f6da5..a3992fa 100644 --- a/gcc/testsuite/lib/target-supports.exp +++ b/gcc/testsuite/lib/target-supports.exp @@ -942,8 +942,7 @@ proc check_effective_target_nonlocal_goto {} { # Return 1 if global constructors are supported, 0 otherwise. proc check_effective_target_global_constructor {} { - if { [istarget nvptx-*-*] - || [istarget bpf-*-*] } { + if { [istarget bpf-*-*] } { return 0 } return 1 diff --git a/libgcc/config/nvptx/crt0.c b/libgcc/config/nvptx/crt0.c index e37a6fb..47e8ec4 100644 --- a/libgcc/config/nvptx/crt0.c +++ b/libgcc/config/nvptx/crt0.c @@ -32,6 +32,16 @@ void *__nvptx_stacks[32] __attribute__((shared,nocommon)); /* Likewise for -muniform-simt. */ unsigned __nvptx_uni[32] __attribute__((shared,nocommon)); +/* Global constructor/destructor support. Dummy; if necessary, overridden via + 'gbl-ctors.c'. */ + +extern void __gbl_ctors (void); + +void __attribute__((weak)) +__gbl_ctors (void) +{ +} + extern void __main (int *, int, void **) __attribute__((kernel)); void @@ -47,5 +57,7 @@ __main (int *rval_ptr, int argc, void **argv) __nvptx_stacks[0] = stack + sizeof stack; __nvptx_uni[0] = 0; + __gbl_ctors (); + exit (main (argc, argv)); } diff --git a/libgcc/config/nvptx/gbl-ctors.c b/libgcc/config/nvptx/gbl-ctors.c new file mode 100644 index 0000000..a2ca053 --- /dev/null +++ b/libgcc/config/nvptx/gbl-ctors.c @@ -0,0 +1,74 @@ +/* Global constructor/destructor support + + Copyright (C) 2024 Free Software Foundation, Inc. + + This file is free software; you can redistribute it and/or modify it + under the terms of the GNU General Public License as published by the + Free Software Foundation; either version 3, or (at your option) any + later version. + + This file is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + General Public License for more details. + + Under Section 7 of GPL version 3, you are granted additional + permissions described in the GCC Runtime Library Exception, version + 3.1, as published by the Free Software Foundation. + + You should have received a copy of the GNU General Public License and + a copy of the GCC Runtime Library Exception along with this program; + see the files COPYING3 and COPYING.RUNTIME respectively. If not, see + . */ + +#include "auto-target.h" + +#ifdef HAVE_STDLIB_H +# include +#endif +#include "gbl-ctors.h" + +extern int atexit (void (*function) (void)); + + +/* Handler functions ('static', in contrast to the 'gbl-ctors.h' + prototypes). */ + +static void __static_do_global_ctors (void); + +static void +__static_do_global_ctors (void) +{ + __SIZE_TYPE__ nptrs = (__SIZE_TYPE__) __CTOR_LIST__[0]; + for (__SIZE_TYPE__ i = nptrs; i >= 1; --i) + __CTOR_LIST__[i] (); +} + +static void __static_do_global_dtors (void); + +static void +__static_do_global_dtors (void) +{ + func_ptr *p = __DTOR_LIST__; + ++p; + for (; *p; ++p) + (*p) (); +} + + +/* For nvptx target configurations, override the 'crt0.c' dummy. */ + +extern void __gbl_ctors (void); + +void +__gbl_ctors (void) +{ + __static_do_global_ctors (); + atexit (__static_do_global_dtors); +} + + +/* The following symbol just provides a means for the nvptx-tools 'ld' to + trigger linking in this file. */ + +int __trigger_gbl_ctors; diff --git a/libgcc/config/nvptx/t-nvptx b/libgcc/config/nvptx/t-nvptx index 49fdb55..260ed63 100644 --- a/libgcc/config/nvptx/t-nvptx +++ b/libgcc/config/nvptx/t-nvptx @@ -6,8 +6,10 @@ LIB2ADD=$(srcdir)/config/nvptx/reduction.c \ LIB2ADD += $(srcdir)/c++-minimal/guard.c LIB2ADDEH= -LIB2FUNCS_EXCLUDE=__main +LIB2FUNCS_EXCLUDE= +# Wrapping of 'main'. +LIB2FUNCS_EXCLUDE += __main crt0.o: $(srcdir)/config/nvptx/crt0.c $(crt_compile) -c $< @@ -15,3 +17,8 @@ crt0.o: $(srcdir)/config/nvptx/crt0.c # support it, and it may cause the build to fail, because of alloca usage, for # example. INHIBIT_LIBC_CFLAGS = -Dinhibit_libc + +# Support for global constructors/destructors is implemented via the +# nvptx-tools 'ld' and the following helpers. +LIB2ADD += $(srcdir)/config/nvptx/gbl-ctors.c +LIB2FUNCS_EXCLUDE += _ctors -- cgit v1.1