target-arm: emulate SWP with atomic_xchg helper

Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1467054136-10430-25-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
This commit is contained in:
Emilio G. Cota 2016-06-27 15:02:10 -04:00 committed by Richard Henderson
parent 354161b37c
commit cf12bce088
1 changed files with 14 additions and 12 deletions

View File

@ -8789,25 +8789,27 @@ static void disas_arm_insn(DisasContext *s, unsigned int insn)
}
tcg_temp_free_i32(addr);
} else {
TCGv taddr;
TCGMemOp opc = s->be_data;
/* SWP instruction */
rm = (insn) & 0xf;
/* ??? This is not really atomic. However we know
we never have multiple CPUs running in parallel,
so it is good enough. */
addr = load_reg(s, rn);
tmp = load_reg(s, rm);
tmp2 = tcg_temp_new_i32();
if (insn & (1 << 22)) {
gen_aa32_ld8u(s, tmp2, addr, get_mem_index(s));
gen_aa32_st8(s, tmp, addr, get_mem_index(s));
opc |= MO_UB;
} else {
gen_aa32_ld32u(s, tmp2, addr, get_mem_index(s));
gen_aa32_st32(s, tmp, addr, get_mem_index(s));
opc |= MO_UL | MO_ALIGN;
}
tcg_temp_free_i32(tmp);
addr = load_reg(s, rn);
taddr = gen_aa32_addr(s, addr, opc);
tcg_temp_free_i32(addr);
store_reg(s, rd, tmp2);
tmp = load_reg(s, rm);
tcg_gen_atomic_xchg_i32(tmp, taddr, tmp,
get_mem_index(s), opc);
tcg_temp_free(taddr);
store_reg(s, rd, tmp);
}
}
} else {