David Faust writes:
> On 3/26/24 07:28, Cupertino Miranda wrote: >> Hi everyone, >> >> This patch is an expected fix for the issue reported by systemd in: >> https://github.com/systemd/systemd/issues/31888 >> Also, Jose Marchesi opened the following bugzilla to report it: >> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114431 >> >> Please notice that the function created was inspired by existing code >> in the function btf_asm_type_ref. >> >> Looking forward to your comments. > > OK, LGTM. > Thanks for the fix! Pushed! Thanks! >> >> Cupertino >> >> >> GCC was defining bts_offset entry to always contain 0. >> When comparing with clang, the same entry is instead a label to the >> respective variable or function. The assembler emits relocations for >> those labels. >> >> gcc/ChangeLog: >> PR target/114431 >> * btfout.cc (get_name_for_datasec_entry): Add function. >> (btf_asm_datasec_entry): Print label when possible. >> >> gcc/testsuite/ChangeLog: >> gcc.dg/debug/btf/btf-datasec-1.c: Correct for new >> implementation. >> gcc.dg/debug/btf/btf-datasec-2.c: Likewise >> gcc.dg/debug/btf/btf-pr106773.c: Likewise >> --- >> gcc/btfout.cc | 30 ++++++++++++++++++- >> .../gcc.dg/debug/btf/btf-datasec-1.c | 6 ++-- >> .../gcc.dg/debug/btf/btf-datasec-2.c | 7 +++-- >> gcc/testsuite/gcc.dg/debug/btf/btf-pr106773.c | 2 +- >> 4 files changed, 39 insertions(+), 6 deletions(-) >> >> diff --git a/gcc/btfout.cc b/gcc/btfout.cc >> index e63289bc554..5f708630e04 100644 >> --- a/gcc/btfout.cc >> +++ b/gcc/btfout.cc >> @@ -1014,13 +1014,41 @@ btf_asm_func_type (ctf_container_ref ctfc, >> ctf_dtdef_ref dtd, ctf_id_t id) >> btf_asm_type_ref ("btt_type", ctfc, get_btf_id (ref_id)); >> } >> >> +/* Collect the name for the DATASEC reference required to be output as a >> + symbol. */ >> + >> +static const char * >> +get_name_for_datasec_entry (ctf_container_ref ctfc, ctf_id_t ref_id) >> +{ >> + if (ref_id >= num_types_added + 1 >> + && ref_id < num_types_added + num_vars_added + 1) >> + { >> + /* Ref to a variable. Should only appear in DATASEC entries. */ >> + ctf_id_t var_id = btf_relative_var_id (ref_id); >> + ctf_dvdef_ref dvd = ctfc->ctfc_vars_list[var_id]; >> + return dvd->dvd_name; >> + } >> + else if (ref_id >= num_types_added + num_vars_added + 1) >> + { >> + /* Ref to a FUNC record. */ >> + size_t func_id = btf_relative_func_id (ref_id); >> + ctf_dtdef_ref ref_type = (*funcs)[func_id]; >> + return get_btf_type_name (ref_type); >> + } >> + return NULL; >> +} >> + >> /* Asm'out a variable entry following a BTF_KIND_DATASEC. */ >> >> static void >> btf_asm_datasec_entry (ctf_container_ref ctfc, struct btf_var_secinfo info) >> { >> + const char *symbol_name = get_name_for_datasec_entry (ctfc, info.type); >> btf_asm_type_ref ("bts_type", ctfc, info.type); >> - dw2_asm_output_data (4, info.offset, "bts_offset"); >> + if (symbol_name == NULL) >> + dw2_asm_output_data (4, info.offset, "bts_offset"); >> + else >> + dw2_asm_output_offset (4, symbol_name, NULL, "bts_offset"); >> dw2_asm_output_data (4, info.size, "bts_size"); >> } >> >> diff --git a/gcc/testsuite/gcc.dg/debug/btf/btf-datasec-1.c >> b/gcc/testsuite/gcc.dg/debug/btf/btf-datasec-1.c >> index 77df88648c5..8557c38c20d 100644 >> --- a/gcc/testsuite/gcc.dg/debug/btf/btf-datasec-1.c >> +++ b/gcc/testsuite/gcc.dg/debug/btf/btf-datasec-1.c >> @@ -19,8 +19,10 @@ >> /* { dg-final { scan-assembler-times "0xf000003\[\t \]+\[^\n\]*btt_info" 2 >> } } */ >> /* { dg-final { scan-assembler-times "0xf000001\[\t \]+\[^\n\]*btt_info" 1 >> } } */ >> >> -/* The offset entry for each variable in a DATSEC should be 0 at compile >> time. */ >> -/* { dg-final { scan-assembler-times "0\[\t \]+\[^\n\]*bts_offset" 7 } } */ >> +/* The offset entry for each variable in a DATSEC should contain a label. >> */ >> +/* { dg-final { scan-assembler-times ".4byte\[\t \]\[a-e\]\[\t >> \]+\[^\n\]*bts_offset" 5 } } */ >> +/* { dg-final { scan-assembler-times "my_cstruct\[\t \]+\[^\n\]*bts_offset" >> 1 } } */ >> +/* { dg-final { scan-assembler-times "bigarr\[\t \]+\[^\n\]*bts_offset" 1 } >> } */ >> >> /* Check that strings for each DATASEC have been added to the BTF string >> table. */ >> /* { dg-final { scan-assembler-times "ascii \".data.0\"\[\t >> \]+\[^\n\]*btf_aux_string" 1 } } */ >> diff --git a/gcc/testsuite/gcc.dg/debug/btf/btf-datasec-2.c >> b/gcc/testsuite/gcc.dg/debug/btf/btf-datasec-2.c >> index d6f3358d6fb..857d830e446 100644 >> --- a/gcc/testsuite/gcc.dg/debug/btf/btf-datasec-2.c >> +++ b/gcc/testsuite/gcc.dg/debug/btf/btf-datasec-2.c >> @@ -9,8 +9,11 @@ >> /* { dg-final { scan-assembler-times " BTF_KIND_DATASEC >> '.foo_sec'\[\\r\\n\]+\[^\\r\\n\]*0xf000001\[\t \]+\[^\n\]*btt_info" 1 } } */ >> /* { dg-final { scan-assembler-times " BTF_KIND_DATASEC >> '.bar_sec'\[\\r\\n\]+\[^\\r\\n\]*0xf000002\[\t \]+\[^\n\]*btt_info" 1 } } */ >> >> -/* Function entries should have offset and size of 0 at compile time. */ >> -/* { dg-final { scan-assembler-times "0\[\t \]+\[^\n\]*bts_offset" 3 } } */ >> +/* Function entries should have offset with a label and size of 0 at >> compile time. */ >> +/* { dg-final { scan-assembler-times "chacha\[\t \]+\[^\n\]*bts_offset" 1 } >> } */ >> +/* { dg-final { scan-assembler-times "bar\[\t \]+\[^\n\]*bts_offset" 1 } } >> */ >> +/* { dg-final { scan-assembler-times "foo\[\t \]+\[^\n\]*bts_offset" 1 } } >> */ >> + >> /* { dg-final { scan-assembler-times "0\[\t \]+\[^\n\]*bts_size" 3 } } */ >> >> extern int foo (int a) __attribute__((section(".foo_sec"))); >> diff --git a/gcc/testsuite/gcc.dg/debug/btf/btf-pr106773.c >> b/gcc/testsuite/gcc.dg/debug/btf/btf-pr106773.c >> index 940f129408d..c06220eb520 100644 >> --- a/gcc/testsuite/gcc.dg/debug/btf/btf-pr106773.c >> +++ b/gcc/testsuite/gcc.dg/debug/btf/btf-pr106773.c >> @@ -11,7 +11,7 @@ >> >> /* { dg-final { scan-assembler-times "ascii \"foo.0\"\[\t >> \]+\[^\n\]*btf_string" 1 } } */ >> >> -/* { dg-final { scan-assembler-times "0\[\t \]+\[^\n\]*bts_offset" 1 } } */ >> +/* { dg-final { scan-assembler-times "foo\[\t \]+\[^\n\]*bts_offset" 1 } } >> */ >> /* { dg-final { scan-assembler-times "1\[\t \]+\[^\n\]*bts_size" 1 } } */ >> >> extern const void foo __attribute__((weak)) __attribute__((section >> (".ksyms")));
