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tcg: Optimize brcond2 and setcond2 ne/eq

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If either the high or low pair can be resolved, we can
simplify to either a constant or to a 32-bit comparison.

Signed-off-by: Richard Henderson <rth@twiddle.net>
This commit is contained in:
Richard Henderson 2014-04-23 22:18:30 -07:00
parent 3ee933c9d4
commit a763551ad5
1 changed files with 94 additions and 0 deletions
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94
tcg/optimize.c
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@ -859,6 +859,7 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
break;
CASE_OP_32_64(setcond):
case INDEX_op_setcond2_i32:
mask = 1;
break;
@ -1193,11 +1194,13 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
tmp = do_constant_folding_cond2(&args[0], &args[2], args[4]);
if (tmp != 2) {
if (tmp) {
do_brcond_true:
reset_all_temps(nb_temps);
s->gen_opc_buf[op_index] = INDEX_op_br;
gen_args[0] = args[5];
gen_args += 1;
} else {
do_brcond_false:
s->gen_opc_buf[op_index] = INDEX_op_nop;
}
} else if ((args[4] == TCG_COND_LT || args[4] == TCG_COND_GE)
@ -1207,6 +1210,7 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
&& temps[args[3]].val == 0) {
/* Simplify LT/GE comparisons vs zero to a single compare
vs the high word of the input. */
do_brcond_high:
reset_all_temps(nb_temps);
s->gen_opc_buf[op_index] = INDEX_op_brcond_i32;
gen_args[0] = args[1];
@ -1214,6 +1218,49 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
gen_args[2] = args[4];
gen_args[3] = args[5];
gen_args += 4;
} else if (args[4] == TCG_COND_EQ) {
/* Simplify EQ comparisons where one of the pairs
can be simplified. */
tmp = do_constant_folding_cond(INDEX_op_brcond_i32,
args[0], args[2], TCG_COND_EQ);
if (tmp == 0) {
goto do_brcond_false;
} else if (tmp == 1) {
goto do_brcond_high;
}
tmp = do_constant_folding_cond(INDEX_op_brcond_i32,
args[1], args[3], TCG_COND_EQ);
if (tmp == 0) {
goto do_brcond_false;
} else if (tmp != 1) {
goto do_default;
}
do_brcond_low:
reset_all_temps(nb_temps);
s->gen_opc_buf[op_index] = INDEX_op_brcond_i32;
gen_args[0] = args[0];
gen_args[1] = args[2];
gen_args[2] = args[4];
gen_args[3] = args[5];
gen_args += 4;
} else if (args[4] == TCG_COND_NE) {
/* Simplify NE comparisons where one of the pairs
can be simplified. */
tmp = do_constant_folding_cond(INDEX_op_brcond_i32,
args[0], args[2], TCG_COND_NE);
if (tmp == 0) {
goto do_brcond_high;
} else if (tmp == 1) {
goto do_brcond_true;
}
tmp = do_constant_folding_cond(INDEX_op_brcond_i32,
args[1], args[3], TCG_COND_NE);
if (tmp == 0) {
goto do_brcond_low;
} else if (tmp == 1) {
goto do_brcond_true;
}
goto do_default;
} else {
goto do_default;
}
@ -1223,6 +1270,7 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
case INDEX_op_setcond2_i32:
tmp = do_constant_folding_cond2(&args[1], &args[3], args[5]);
if (tmp != 2) {
do_setcond_const:
s->gen_opc_buf[op_index] = INDEX_op_movi_i32;
tcg_opt_gen_movi(gen_args, args[0], tmp);
gen_args += 2;
@ -1233,13 +1281,59 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
&& temps[args[4]].val == 0) {
/* Simplify LT/GE comparisons vs zero to a single compare
vs the high word of the input. */
do_setcond_high:
s->gen_opc_buf[op_index] = INDEX_op_setcond_i32;
reset_temp(args[0]);
temps[args[0]].mask = 1;
gen_args[0] = args[0];
gen_args[1] = args[2];
gen_args[2] = args[4];
gen_args[3] = args[5];
gen_args += 4;
} else if (args[5] == TCG_COND_EQ) {
/* Simplify EQ comparisons where one of the pairs
can be simplified. */
tmp = do_constant_folding_cond(INDEX_op_setcond_i32,
args[1], args[3], TCG_COND_EQ);
if (tmp == 0) {
goto do_setcond_const;
} else if (tmp == 1) {
goto do_setcond_high;
}
tmp = do_constant_folding_cond(INDEX_op_setcond_i32,
args[2], args[4], TCG_COND_EQ);
if (tmp == 0) {
goto do_setcond_high;
} else if (tmp != 1) {
goto do_default;
}
do_setcond_low:
reset_temp(args[0]);
temps[args[0]].mask = 1;
s->gen_opc_buf[op_index] = INDEX_op_setcond_i32;
gen_args[0] = args[0];
gen_args[1] = args[1];
gen_args[2] = args[3];
gen_args[3] = args[5];
gen_args += 4;
} else if (args[5] == TCG_COND_NE) {
/* Simplify NE comparisons where one of the pairs
can be simplified. */
tmp = do_constant_folding_cond(INDEX_op_setcond_i32,
args[1], args[3], TCG_COND_NE);
if (tmp == 0) {
goto do_setcond_high;
} else if (tmp == 1) {
goto do_setcond_const;
}
tmp = do_constant_folding_cond(INDEX_op_setcond_i32,
args[2], args[4], TCG_COND_NE);
if (tmp == 0) {
goto do_setcond_low;
} else if (tmp == 1) {
goto do_setcond_const;
}
goto do_default;
} else {
goto do_default;
}