target-i386: use CCPrepare to generate conditional jumps

This simplifies all the jump generation code.  CCPrepare allows the
code to create an efficient brcond always, so there is no need to
duplicate the setcc and jcc code.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
This commit is contained in:
Paolo Bonzini 2012-10-07 15:53:23 +02:00 committed by Richard Henderson
parent 276e6b5f06
commit 943131ca98

View file

@ -1178,117 +1178,16 @@ static CCPrepare gen_prepare_cc(DisasContext *s, int b, TCGv reg)
value 'b'. In the fast case, T0 is guaranted not to be used. */
static inline void gen_jcc1(DisasContext *s, int b, int l1)
{
int inv, jcc_op, size, cond;
TCGv t0;
CCPrepare cc = gen_prepare_cc(s, b, cpu_T[0]);
inv = b & 1;
jcc_op = (b >> 1) & 7;
switch (s->cc_op) {
/* we optimize the cmp/jcc case */
case CC_OP_SUBB:
case CC_OP_SUBW:
case CC_OP_SUBL:
case CC_OP_SUBQ:
size = s->cc_op - CC_OP_SUBB;
switch(jcc_op) {
case JCC_Z:
fast_jcc_z:
t0 = gen_ext_tl(cpu_tmp0, cpu_cc_dst, size, false);
tcg_gen_brcondi_tl(inv ? TCG_COND_NE : TCG_COND_EQ, t0, 0, l1);
break;
case JCC_S:
fast_jcc_s:
t0 = gen_ext_tl(cpu_tmp0, cpu_cc_dst, size, true);
tcg_gen_brcondi_tl(inv ? TCG_COND_GE : TCG_COND_LT, t0, 0, l1);
break;
case JCC_B:
cond = inv ? TCG_COND_GEU : TCG_COND_LTU;
goto fast_jcc_b;
case JCC_BE:
cond = inv ? TCG_COND_GTU : TCG_COND_LEU;
fast_jcc_b:
tcg_gen_add_tl(cpu_tmp4, cpu_cc_dst, cpu_cc_src);
gen_extu(size, cpu_tmp4);
t0 = gen_ext_tl(cpu_tmp0, cpu_cc_src, size, false);
tcg_gen_brcond_tl(cond, cpu_tmp4, t0, l1);
break;
case JCC_L:
cond = inv ? TCG_COND_GE : TCG_COND_LT;
goto fast_jcc_l;
case JCC_LE:
cond = inv ? TCG_COND_GT : TCG_COND_LE;
fast_jcc_l:
tcg_gen_add_tl(cpu_tmp4, cpu_cc_dst, cpu_cc_src);
gen_exts(size, cpu_tmp4);
t0 = gen_ext_tl(cpu_tmp0, cpu_cc_src, size, true);
tcg_gen_brcond_tl(cond, cpu_tmp4, t0, l1);
break;
default:
goto slow_jcc;
}
break;
/* some jumps are easy to compute */
case CC_OP_ADDB:
case CC_OP_ADDW:
case CC_OP_ADDL:
case CC_OP_ADDQ:
case CC_OP_ADCB:
case CC_OP_ADCW:
case CC_OP_ADCL:
case CC_OP_ADCQ:
case CC_OP_SBBB:
case CC_OP_SBBW:
case CC_OP_SBBL:
case CC_OP_SBBQ:
case CC_OP_LOGICB:
case CC_OP_LOGICW:
case CC_OP_LOGICL:
case CC_OP_LOGICQ:
case CC_OP_INCB:
case CC_OP_INCW:
case CC_OP_INCL:
case CC_OP_INCQ:
case CC_OP_DECB:
case CC_OP_DECW:
case CC_OP_DECL:
case CC_OP_DECQ:
case CC_OP_SHLB:
case CC_OP_SHLW:
case CC_OP_SHLL:
case CC_OP_SHLQ:
case CC_OP_SARB:
case CC_OP_SARW:
case CC_OP_SARL:
case CC_OP_SARQ:
switch(jcc_op) {
case JCC_Z:
size = (s->cc_op - CC_OP_ADDB) & 3;
goto fast_jcc_z;
case JCC_S:
size = (s->cc_op - CC_OP_ADDB) & 3;
goto fast_jcc_s;
default:
goto slow_jcc;
}
break;
default:
slow_jcc:
gen_setcc1(s, b, cpu_T[0]);
tcg_gen_brcondi_tl(TCG_COND_NE, cpu_T[0], 0, l1);
break;
if (cc.mask != -1) {
tcg_gen_andi_tl(cpu_T[0], cc.reg, cc.mask);
cc.reg = cpu_T[0];
}
if (cc.use_reg2) {
tcg_gen_brcond_tl(cc.cond, cc.reg, cc.reg2, l1);
} else {
tcg_gen_brcondi_tl(cc.cond, cc.reg, cc.imm, l1);
}
}