stan/jdk-24
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

8344355: Register corruption in MacroAssembler::lookup_secondary_supers_table_var: x86-64 only

Browse Source 
Reviewed-by: vlivanov, martin, dlong, asemenov
This commit is contained in:
Andrew Haley 2024-11-27 10:27:58 +00:00
parent 82137db24d
commit eb0d1ce948
1 changed files with 6 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
src/hotspot/cpu/x86/macroAssembler_x86.cpp
View File

@ -4912,6 +4912,10 @@ void MacroAssembler::population_count(Register dst, Register src,
}
bind(done);
}
#ifdef ASSERT
mov64(scratch1, 0xCafeBabeDeadBeef);
movq(scratch2, scratch1);
#endif
}
// Ensure that the inline code and the stub are using the same registers.
@ -5113,6 +5117,7 @@ void MacroAssembler::lookup_secondary_supers_table_var(Register r_sub_klass,
const Register r_array_base = *available_regs++;
// Get the first array index that can contain super_klass into r_array_index.
// Note: Clobbers r_array_base and slot.
population_count(r_array_index, r_array_index, /*temp2*/r_array_base, /*temp3*/slot);
// NB! r_array_index is off by 1. It is compensated by keeping r_array_base off by 1 word.
@ -5130,7 +5135,7 @@ void MacroAssembler::lookup_secondary_supers_table_var(Register r_sub_klass,
jccb(Assembler::equal, L_success);
// Restore slot to its true value
xorl(slot, (u1)(Klass::SECONDARY_SUPERS_TABLE_SIZE - 1)); // slot ^ 63 === 63 - slot (mod 64)
movb(slot, Address(r_super_klass, Klass::hash_slot_offset()));
// Linear probe. Rotate the bitmap so that the next bit to test is
// in Bit 1.