Commit 7fa8e26d authored by Michael Beck's avatar Michael Beck
Browse files

handle a/-1 and a%-1 right

[r15455]
parent bfdabdae
......@@ -2218,32 +2218,47 @@ static ir_node *transform_node_Mul(ir_node *n) {
*/
static ir_node *transform_node_Div(ir_node *n) {
tarval *tv = value_of(n);
ir_mode *mode = get_Div_resmode(n);
ir_node *value = n;
if (tv != tarval_bad) {
value = new_Const(get_tarval_mode(tv), tv);
DBG_OPT_CSTEVAL(n, value);
goto make_tuple;
} else {
ir_node *a = get_Div_left(n);
ir_node *b = get_Div_right(n);
ir_node *dummy;
ir_mode *mode = get_irn_mode(n);
if (a == b && value_not_zero(a, &dummy)) {
/* BEWARE: we can optimize a/a to 1 only if this cannot cause a exception */
value = new_Const(mode, get_mode_one(mode));
DBG_OPT_CSTEVAL(n, value);
goto make_tuple;
} else {
if (mode_is_signed(mode) && is_Const(b)) {
tarval *tv = get_Const_tarval(b);
if (tv == get_mode_minus_one(mode)) {
/* a / -1 */
value = new_rd_Minus(get_irn_dbg_info(n), current_ir_graph, get_irn_n(n, -1), a, mode);
DBG_OPT_CSTEVAL(n, value);
goto make_tuple;
}
}
/* Try architecture dependent optimization */
value = arch_dep_replace_div_by_const(n);
}
}
if (value != n) {
ir_node *mem, *blk;
make_tuple:
/* Turn Div into a tuple (mem, jmp, bad, value) */
ir_node *mem = get_Div_mem(n);
ir_node *blk = get_irn_n(n, -1);
mem = get_Div_mem(n);
blk = get_irn_n(n, -1);
turn_into_tuple(n, pn_Div_max);
set_Tuple_pred(n, pn_Div_M, mem);
......@@ -2259,32 +2274,47 @@ static ir_node *transform_node_Div(ir_node *n) {
*/
static ir_node *transform_node_Mod(ir_node *n) {
tarval *tv = value_of(n);
ir_mode *mode = get_Mod_resmode(n);
ir_node *value = n;
if (tv != tarval_bad) {
value = new_Const(get_tarval_mode(tv), tv);
DBG_OPT_CSTEVAL(n, value);
goto make_tuple;
} else {
ir_node *a = get_Mod_left(n);
ir_node *b = get_Mod_right(n);
ir_node *dummy;
ir_mode *mode = get_Mod_resmode(n);
if (a == b && value_not_zero(a, &dummy)) {
/* BEWARE: we can optimize a%a to 0 only if this cannot cause a exception */
value = new_Const(mode, get_mode_null(mode));
DBG_OPT_CSTEVAL(n, value);
goto make_tuple;
} else {
if (mode_is_signed(mode) && is_Const(b)) {
tarval *tv = get_Const_tarval(b);
if (tv == get_mode_minus_one(mode)) {
/* a % -1 = 0 */
value = new_Const(mode, get_mode_null(mode));
DBG_OPT_CSTEVAL(n, value);
goto make_tuple;
}
}
/* Try architecture dependent optimization */
value = arch_dep_replace_mod_by_const(n);
}
}
if (value != n) {
ir_node *mem, *blk;
make_tuple:
/* Turn Mod into a tuple (mem, jmp, bad, value) */
ir_node *mem = get_Mod_mem(n);
ir_node *blk = get_irn_n(n, -1);
mem = get_Mod_mem(n);
blk = get_irn_n(n, -1);
turn_into_tuple(n, pn_Mod_max);
set_Tuple_pred(n, pn_Mod_M, mem);
......@@ -2299,21 +2329,19 @@ static ir_node *transform_node_Mod(ir_node *n) {
* Transform a DivMod node.
*/
static ir_node *transform_node_DivMod(ir_node *n) {
int evaluated = 0;
ir_node *dummy;
ir_node *a = get_DivMod_left(n);
ir_node *b = get_DivMod_right(n);
ir_mode *mode = get_DivMod_resmode(n);
tarval *ta = value_of(a);
tarval *tb = value_of(b);
int evaluated = 0;
if (tb != tarval_bad) {
if (tb == get_mode_one(get_tarval_mode(tb))) {
b = new_Const (mode, get_mode_null(mode));
evaluated = 1;
b = new_Const(mode, get_mode_null(mode));
DBG_OPT_CSTEVAL(n, b);
goto make_tuple;
} else if (ta != tarval_bad) {
tarval *resa, *resb;
resa = tarval_div(ta, tb);
......@@ -2323,10 +2351,15 @@ static ir_node *transform_node_DivMod(ir_node *n) {
if (resb == tarval_bad) return n; /* Causes exception! */
a = new_Const(mode, resa);
b = new_Const(mode, resb);
evaluated = 1;
DBG_OPT_CSTEVAL(n, a);
DBG_OPT_CSTEVAL(n, b);
goto make_tuple;
} else if (mode_is_signed(mode) && tb == get_mode_minus_one(mode)) {
a = new_rd_Minus(get_irn_dbg_info(n), current_ir_graph, get_irn_n(n, -1), a, mode);
b = new_Const(mode, get_mode_null(mode));
DBG_OPT_CSTEVAL(n, a);
DBG_OPT_CSTEVAL(n, b);
goto make_tuple;
} else { /* Try architecture dependent optimization */
arch_dep_replace_divmod_by_const(&a, &b, n);
evaluated = a != NULL;
......@@ -2338,7 +2371,7 @@ static ir_node *transform_node_DivMod(ir_node *n) {
b = new_Const(mode, get_mode_null(mode));
DBG_OPT_CSTEVAL(n, a);
DBG_OPT_CSTEVAL(n, b);
evaluated = 1;
goto make_tuple;
} else {
/* BEWARE: it is NOT possible to optimize a/a to 1, as this may cause a exception */
return n;
......@@ -2346,12 +2379,15 @@ static ir_node *transform_node_DivMod(ir_node *n) {
} else if (ta == get_mode_null(mode) && value_not_zero(b, &dummy)) {
/* 0 / non-Const = 0 */
b = a;
evaluated = 1;
goto make_tuple;
}
if (evaluated) { /* replace by tuple */
ir_node *mem = get_DivMod_mem(n);
ir_node *blk = get_irn_n(n, -1);
ir_node *mem, *blk;
make_tuple:
mem = get_DivMod_mem(n);
blk = get_irn_n(n, -1);
turn_into_tuple(n, pn_DivMod_max);
set_Tuple_pred(n, pn_DivMod_M, mem);
set_Tuple_pred(n, pn_DivMod_X_regular, new_r_Jmp(current_ir_graph, blk));
......
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