def call_releasegil_addr_and_move_real_arguments(self):
assert not self.asm._is_asmgcc()
from rpython.jit.backend.arm.regalloc import CoreRegisterManager
with saved_registers(self.mc,
CoreRegisterManager.save_around_call_regs):
self.mc.BL(self.asm.releasegil_addr)
if not we_are_translated(): # for testing: we should not access
self.mc.ADD_ri(r.fp.value, r.fp.value, 1) # fp any more
def move_real_result_and_call_reacqgil_addr(self):
# save the result we just got
assert not self.asm._is_asmgcc()
gpr_to_save, vfp_to_save = self.get_result_locs()
with saved_registers(self.mc, gpr_to_save, vfp_to_save):
self.mc.BL(self.asm.reacqgil_addr)
if not we_are_translated(): # for testing: now we can accesss
self.mc.SUB_ri(r.fp.value, r.fp.value, 1) # fp again
def move_real_result_and_call_reacqgil_addr(self, fastgil):
# try to reacquire the lock. The registers r5 to r7 are still
# valid from before the call:
# r5 == &root_stack_top
# r6 == fastgil
# r7 == previous value of root_stack_top
# r8 == our thread ident
self.mc.LDREX(r.r3.value, r.r6.value) # load the lock value
self.mc.CMP_ri(r.r3.value, 0) # is the lock free?
self.mc.STREX(r.r3.value, r.r8.value, r.r6.value, c=c.EQ)
# try to claim the lock
self.mc.CMP_ri(r.r3.value, 0, cond=c.EQ) # did this succeed?
if self.asm.cpu.cpuinfo.arch_version >= 7:
self.mc.DMB()
# the success of the lock acquisition is defined by
# 'EQ is true', or equivalently by 'r3 == 0'.
#
if self.asm.cpu.gc_ll_descr.gcrootmap:
# When doing a call_release_gil with shadowstack, there
# is the risk that the 'rpy_fastgil' was free but the
# current shadowstack can be the one of a different
# thread. So here we check if the shadowstack pointer
# is still the same as before we released the GIL (saved
# in 'r7'), and if not, we fall back to 'reacqgil_addr'.
self.mc.LDR_ri(r.ip.value, r.r5.value, cond=c.EQ)
self.mc.CMP_rr(r.ip.value, r.r7.value, cond=c.EQ)
b1_location = self.mc.currpos()
self.mc.BKPT() # BEQ below
# there are two cases here: either EQ was false from
# the beginning, or EQ was true at first but the CMP
# made it false. In the second case we need to
# release the fastgil here. We know which case it is
# by checking again r3.
self.mc.CMP_ri(r.r3.value, 0)
self.mc.STR_ri(r.r3.value, r.r6.value, cond=c.EQ)
else:
b1_location = self.mc.currpos()
self.mc.BKPT() # BEQ below
#
# save the result we just got
gpr_to_save, vfp_to_save = self.get_result_locs()
with saved_registers(self.mc, gpr_to_save, vfp_to_save):
self.mc.BL(self.asm.reacqgil_addr)
# replace b1_location with B(here, c.EQ)
pmc = OverwritingBuilder(self.mc, b1_location, WORD)
pmc.B_offs(self.mc.currpos(), c.EQ)
if not we_are_translated(): # for testing: now we can accesss
self.mc.SUB_ri(r.fp.value, r.fp.value, 1) # fp again
def move_real_result_and_call_reacqgil_addr(self, fastgil):
# try to reacquire the lock. The registers r5 to r7 are still
# valid from before the call:
# r5 == &root_stack_top
# r6 == fastgil
# r7 == previous value of root_stack_top
self.mc.LDREX(r.r3.value, r.r6.value) # load the lock value
self.mc.MOV_ri(r.ip.value, 1)
self.mc.CMP_ri(r.r3.value, 0) # is the lock free?
self.mc.STREX(r.r3.value, r.ip.value, r.r6.value, c=c.EQ)
# try to claim the lock
self.mc.CMP_ri(r.r3.value, 0, cond=c.EQ) # did this succeed?
if self.asm.cpu.cpuinfo.arch_version >= 7:
self.mc.DMB()
# the success of the lock acquisition is defined by
# 'EQ is true', or equivalently by 'r3 == 0'.
#
if self.asm.cpu.gc_ll_descr.gcrootmap:
# When doing a call_release_gil with shadowstack, there
# is the risk that the 'rpy_fastgil' was free but the
# current shadowstack can be the one of a different
# thread. So here we check if the shadowstack pointer
# is still the same as before we released the GIL (saved
# in 'r7'), and if not, we fall back to 'reacqgil_addr'.
self.mc.LDR_ri(r.ip.value, r.r5.value, cond=c.EQ)
self.mc.CMP_rr(r.ip.value, r.r7.value, cond=c.EQ)
b1_location = self.mc.currpos()
self.mc.BKPT() # BEQ below
# there are two cases here: either EQ was false from
# the beginning, or EQ was true at first but the CMP
# made it false. In the second case we need to
# release the fastgil here. We know which case it is
# by checking again r3.
self.mc.CMP_ri(r.r3.value, 0)
self.mc.STR_ri(r.r3.value, r.r6.value, cond=c.EQ)
else:
b1_location = self.mc.currpos()
self.mc.BKPT() # BEQ below
#
# save the result we just got
gpr_to_save, vfp_to_save = self.get_result_locs()
with saved_registers(self.mc, gpr_to_save, vfp_to_save):
self.mc.BL(self.asm.reacqgil_addr)
# replace b1_location with B(here, c.EQ)
pmc = OverwritingBuilder(self.mc, b1_location, WORD)
pmc.B_offs(self.mc.currpos(), c.EQ)
if not we_are_translated(): # for testing: now we can accesss
self.mc.SUB_ri(r.fp.value, r.fp.value, 1) # fp again
