| Message ID | 20220911222630.338330-3-pbonzini@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | target/i386: two fixes for cmpxchg | expand |
On 9/11/22 23:26, Paolo Bonzini wrote:
> Do not set all the flags, they are untouched other than ZF.
Um, no, second sentence:
# The ZF flag is set if the values in the destination operand and register
# AL, AX, or EAX are equal; otherwise it is
cleared. The CF, PF, AF, SF,
# and OF flags are set according to the results of the comparison operation.
r~
diff --git a/target/i386/tcg/translate.c b/target/i386/tcg/translate.c index 0e9237d627..488a617d14 100644 --- a/target/i386/tcg/translate.c +++ b/target/i386/tcg/translate.c @@ -5548,10 +5548,12 @@ static target_ulong disas_insn(DisasContext *s, CPUState *cpu) gen_op_mov_reg_v(s, ot, R_EAX, oldv); } } - tcg_gen_mov_tl(cpu_cc_src, oldv); - tcg_gen_mov_tl(s->cc_srcT, cmpv); - tcg_gen_sub_tl(cpu_cc_dst, cmpv, oldv); - set_cc_op(s, CC_OP_SUBB + ot); + + gen_compute_eflags(s); + tcg_gen_andi_tl(cpu_cc_src, cpu_cc_src, ~CC_Z); + tcg_gen_addi_tl(s->T0, cpu_cc_src, CC_Z); + tcg_gen_movcond_tl(TCG_COND_EQ, cpu_cc_src, oldv, cmpv, s->T0, cpu_cc_src); + tcg_temp_free(oldv); tcg_temp_free(newv); tcg_temp_free(cmpv);
Do not set all the flags, they are untouched other than ZF. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> --- target/i386/tcg/translate.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-)