tcg/optimize: Split out fold_xi_to_x

Pull the "op r, a, i => mov r, a" optimization into a function,
and use them in the outer-most logical operations.

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 2021-08-25 20:28:53 -07:00
parent 9caca88a76
commit a63ce0e9cb

View File

@ -749,6 +749,15 @@ static bool fold_xi_to_i(OptContext *ctx, TCGOp *op, uint64_t i)
return false;
}
/* If the binary operation has second argument @i, fold to identity. */
static bool fold_xi_to_x(OptContext *ctx, TCGOp *op, uint64_t i)
{
if (arg_is_const(op->args[2]) && arg_info(op->args[2])->val == i) {
return tcg_opt_gen_mov(ctx, op, op->args[0], op->args[1]);
}
return false;
}
/* If the binary operation has second argument @i, fold to NOT. */
static bool fold_xi_to_not(OptContext *ctx, TCGOp *op, uint64_t i)
{
@ -787,7 +796,11 @@ static bool fold_xx_to_x(OptContext *ctx, TCGOp *op)
static bool fold_add(OptContext *ctx, TCGOp *op)
{
return fold_const2(ctx, op);
if (fold_const2(ctx, op) ||
fold_xi_to_x(ctx, op, 0)) {
return true;
}
return false;
}
static bool fold_addsub2_i32(OptContext *ctx, TCGOp *op, bool add)
@ -827,6 +840,7 @@ static bool fold_and(OptContext *ctx, TCGOp *op)
{
if (fold_const2(ctx, op) ||
fold_xi_to_i(ctx, op, 0) ||
fold_xi_to_x(ctx, op, -1) ||
fold_xx_to_x(ctx, op)) {
return true;
}
@ -837,6 +851,7 @@ static bool fold_andc(OptContext *ctx, TCGOp *op)
{
if (fold_const2(ctx, op) ||
fold_xx_to_i(ctx, op, 0) ||
fold_xi_to_x(ctx, op, 0) ||
fold_ix_to_not(ctx, op, -1)) {
return true;
}
@ -1044,6 +1059,7 @@ static bool fold_dup2(OptContext *ctx, TCGOp *op)
static bool fold_eqv(OptContext *ctx, TCGOp *op)
{
if (fold_const2(ctx, op) ||
fold_xi_to_x(ctx, op, -1) ||
fold_xi_to_not(ctx, op, 0)) {
return true;
}
@ -1237,6 +1253,7 @@ static bool fold_not(OptContext *ctx, TCGOp *op)
static bool fold_or(OptContext *ctx, TCGOp *op)
{
if (fold_const2(ctx, op) ||
fold_xi_to_x(ctx, op, 0) ||
fold_xx_to_x(ctx, op)) {
return true;
}
@ -1246,6 +1263,7 @@ static bool fold_or(OptContext *ctx, TCGOp *op)
static bool fold_orc(OptContext *ctx, TCGOp *op)
{
if (fold_const2(ctx, op) ||
fold_xi_to_x(ctx, op, -1) ||
fold_ix_to_not(ctx, op, 0)) {
return true;
}
@ -1365,7 +1383,11 @@ static bool fold_sextract(OptContext *ctx, TCGOp *op)
static bool fold_shift(OptContext *ctx, TCGOp *op)
{
return fold_const2(ctx, op);
if (fold_const2(ctx, op) ||
fold_xi_to_x(ctx, op, 0)) {
return true;
}
return false;
}
static bool fold_sub_to_neg(OptContext *ctx, TCGOp *op)
@ -1408,6 +1430,7 @@ static bool fold_sub(OptContext *ctx, TCGOp *op)
{
if (fold_const2(ctx, op) ||
fold_xx_to_i(ctx, op, 0) ||
fold_xi_to_x(ctx, op, 0) ||
fold_sub_to_neg(ctx, op)) {
return true;
}
@ -1423,6 +1446,7 @@ static bool fold_xor(OptContext *ctx, TCGOp *op)
{
if (fold_const2(ctx, op) ||
fold_xx_to_i(ctx, op, 0) ||
fold_xi_to_x(ctx, op, 0) ||
fold_xi_to_not(ctx, op, -1)) {
return true;
}
@ -1546,39 +1570,6 @@ void tcg_optimize(TCGContext *s)
break;
}
/* Simplify expression for "op r, a, const => mov r, a" cases */
switch (opc) {
CASE_OP_32_64_VEC(add):
CASE_OP_32_64_VEC(sub):
CASE_OP_32_64_VEC(or):
CASE_OP_32_64_VEC(xor):
CASE_OP_32_64_VEC(andc):
CASE_OP_32_64(shl):
CASE_OP_32_64(shr):
CASE_OP_32_64(sar):
CASE_OP_32_64(rotl):
CASE_OP_32_64(rotr):
if (!arg_is_const(op->args[1])
&& arg_is_const(op->args[2])
&& arg_info(op->args[2])->val == 0) {
tcg_opt_gen_mov(&ctx, op, op->args[0], op->args[1]);
continue;
}
break;
CASE_OP_32_64_VEC(and):
CASE_OP_32_64_VEC(orc):
CASE_OP_32_64(eqv):
if (!arg_is_const(op->args[1])
&& arg_is_const(op->args[2])
&& arg_info(op->args[2])->val == -1) {
tcg_opt_gen_mov(&ctx, op, op->args[0], op->args[1]);
continue;
}
break;
default:
break;
}
/* Simplify using known-zero bits. Currently only ops with a single
output argument is supported. */
z_mask = -1;