tcg/optimize: Split out fold_setcond2

Reduce some code duplication by folding the NE and EQ cases.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Richard Henderson 2021-08-24 09:09:35 -07:00
parent 2f9f08ba43
commit bc47b1aa5b

View File

@ -854,6 +854,75 @@ static bool fold_remainder(OptContext *ctx, TCGOp *op)
return fold_const2(ctx, op);
}
static bool fold_setcond2(OptContext *ctx, TCGOp *op)
{
TCGCond cond = op->args[5];
int i = do_constant_folding_cond2(&op->args[1], &op->args[3], cond);
int inv = 0;
if (i >= 0) {
goto do_setcond_const;
}
switch (cond) {
case TCG_COND_LT:
case TCG_COND_GE:
/*
* Simplify LT/GE comparisons vs zero to a single compare
* vs the high word of the input.
*/
if (arg_is_const(op->args[3]) && arg_info(op->args[3])->val == 0 &&
arg_is_const(op->args[4]) && arg_info(op->args[4])->val == 0) {
goto do_setcond_high;
}
break;
case TCG_COND_NE:
inv = 1;
QEMU_FALLTHROUGH;
case TCG_COND_EQ:
/*
* Simplify EQ/NE comparisons where one of the pairs
* can be simplified.
*/
i = do_constant_folding_cond(INDEX_op_setcond_i32, op->args[1],
op->args[3], cond);
switch (i ^ inv) {
case 0:
goto do_setcond_const;
case 1:
goto do_setcond_high;
}
i = do_constant_folding_cond(INDEX_op_setcond_i32, op->args[2],
op->args[4], cond);
switch (i ^ inv) {
case 0:
goto do_setcond_const;
case 1:
op->args[2] = op->args[3];
op->args[3] = cond;
op->opc = INDEX_op_setcond_i32;
break;
}
break;
default:
break;
do_setcond_high:
op->args[1] = op->args[2];
op->args[2] = op->args[4];
op->args[3] = cond;
op->opc = INDEX_op_setcond_i32;
break;
}
return false;
do_setcond_const:
return tcg_opt_gen_movi(ctx, op, op->args[0], i);
}
static bool fold_shift(OptContext *ctx, TCGOp *op)
{
return fold_const2(ctx, op);
@ -1653,79 +1722,6 @@ void tcg_optimize(TCGContext *s)
}
break;
case INDEX_op_setcond2_i32:
i = do_constant_folding_cond2(&op->args[1], &op->args[3],
op->args[5]);
if (i >= 0) {
do_setcond_const:
tcg_opt_gen_movi(&ctx, op, op->args[0], i);
continue;
}
if ((op->args[5] == TCG_COND_LT || op->args[5] == TCG_COND_GE)
&& arg_is_const(op->args[3])
&& arg_info(op->args[3])->val == 0
&& arg_is_const(op->args[4])
&& arg_info(op->args[4])->val == 0) {
/* Simplify LT/GE comparisons vs zero to a single compare
vs the high word of the input. */
do_setcond_high:
reset_temp(op->args[0]);
arg_info(op->args[0])->z_mask = 1;
op->opc = INDEX_op_setcond_i32;
op->args[1] = op->args[2];
op->args[2] = op->args[4];
op->args[3] = op->args[5];
break;
}
if (op->args[5] == TCG_COND_EQ) {
/* Simplify EQ comparisons where one of the pairs
can be simplified. */
i = do_constant_folding_cond(INDEX_op_setcond_i32,
op->args[1], op->args[3],
TCG_COND_EQ);
if (i == 0) {
goto do_setcond_const;
} else if (i > 0) {
goto do_setcond_high;
}
i = do_constant_folding_cond(INDEX_op_setcond_i32,
op->args[2], op->args[4],
TCG_COND_EQ);
if (i == 0) {
goto do_setcond_high;
} else if (i < 0) {
break;
}
do_setcond_low:
reset_temp(op->args[0]);
arg_info(op->args[0])->z_mask = 1;
op->opc = INDEX_op_setcond_i32;
op->args[2] = op->args[3];
op->args[3] = op->args[5];
break;
}
if (op->args[5] == TCG_COND_NE) {
/* Simplify NE comparisons where one of the pairs
can be simplified. */
i = do_constant_folding_cond(INDEX_op_setcond_i32,
op->args[1], op->args[3],
TCG_COND_NE);
if (i == 0) {
goto do_setcond_high;
} else if (i > 0) {
goto do_setcond_const;
}
i = do_constant_folding_cond(INDEX_op_setcond_i32,
op->args[2], op->args[4],
TCG_COND_NE);
if (i == 0) {
goto do_setcond_low;
} else if (i > 0) {
goto do_setcond_const;
}
}
break;
default:
break;
@ -1813,6 +1809,9 @@ void tcg_optimize(TCGContext *s)
CASE_OP_32_64(shr):
done = fold_shift(&ctx, op);
break;
case INDEX_op_setcond2_i32:
done = fold_setcond2(&ctx, op);
break;
CASE_OP_32_64_VEC(sub):
done = fold_sub(&ctx, op);
break;