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path: root/simplify.c
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Diffstat (limited to 'simplify.c')
-rw-r--r--simplify.c110
1 files changed, 78 insertions, 32 deletions
diff --git a/simplify.c b/simplify.c
index 99f1d045..02709ce4 100644
--- a/simplify.c
+++ b/simplify.c
@@ -1178,38 +1178,52 @@ static int simplify_compare_constant(struct instruction *insn, long long value)
switch (insn->opcode) {
case OP_SET_LT:
+ if (!value)
+ break;
if (value == sign_bit(size)) // (x < SMIN) --> 0
return replace_with_pseudo(insn, value_pseudo(0));
if (value == sign_mask(size)) // (x < SMAX) --> (x != SMAX)
return replace_opcode(insn, OP_SET_NE);
if (value == sign_bit(size) + 1)// (x < SMIN + 1) --> (x == SMIN)
return replace_binop_value(insn, OP_SET_EQ, sign_bit(size));
- changed |= replace_binop_value(insn, OP_SET_LE, (value - 1) & bits);
+ if (!(value & sign_bit(size)))
+ changed |= replace_binop_value(insn, OP_SET_LE, (value - 1) & bits);
break;
case OP_SET_LE:
+ if (!value)
+ break;
if (value == sign_mask(size)) // (x <= SMAX) --> 1
return replace_with_pseudo(insn, value_pseudo(1));
if (value == sign_bit(size)) // (x <= SMIN) --> (x == SMIN)
return replace_opcode(insn, OP_SET_EQ);
if (value == sign_mask(size) - 1) // (x <= SMAX - 1) --> (x != SMAX)
return replace_binop_value(insn, OP_SET_NE, sign_mask(size));
+ if (value & sign_bit(size))
+ changed |= replace_binop_value(insn, OP_SET_LT, (value + 1) & bits);
break;
case OP_SET_GE:
+ if (!value)
+ break;
if (value == sign_bit(size)) // (x >= SMIN) --> 1
return replace_with_pseudo(insn, value_pseudo(1));
if (value == sign_mask(size)) // (x >= SMAX) --> (x == SMAX)
return replace_opcode(insn, OP_SET_EQ);
if (value == sign_bit(size) + 1)// (x >= SMIN + 1) --> (x != SMIN)
return replace_binop_value(insn, OP_SET_NE, sign_bit(size));
- changed |= replace_binop_value(insn, OP_SET_GT, (value - 1) & bits);
+ if (!(value & sign_bit(size)))
+ changed |= replace_binop_value(insn, OP_SET_GT, (value - 1) & bits);
break;
case OP_SET_GT:
+ if (!value)
+ break;
if (value == sign_mask(size)) // (x > SMAX) --> 0
return replace_with_pseudo(insn, value_pseudo(0));
if (value == sign_bit(size)) // (x > SMIN) --> (x != SMIN)
return replace_opcode(insn, OP_SET_NE);
if (value == sign_mask(size) - 1) // (x > SMAX - 1) --> (x == SMAX)
return replace_binop_value(insn, OP_SET_EQ, sign_mask(size));
+ if (value & sign_bit(size))
+ changed |= replace_binop_value(insn, OP_SET_GE, (value + 1) & bits);
break;
case OP_SET_B:
@@ -1275,8 +1289,10 @@ static int simplify_compare_constant(struct instruction *insn, long long value)
if (value == bits && is_power_of_2(bits))
return replace_binop_value(insn, OP_SET_EQ, 0);
break;
- case OP_SET_LE:
+ case OP_SET_LE: case OP_SET_LT:
value = sign_extend(value, def->size);
+ if (insn->opcode == OP_SET_LT)
+ value -= 1;
if (bits & sign_bit(def->size))
break;
if (value < 0)
@@ -1286,8 +1302,10 @@ static int simplify_compare_constant(struct instruction *insn, long long value)
if (value == 0)
return replace_opcode(insn, OP_SET_EQ);
break;
- case OP_SET_GT:
+ case OP_SET_GT: case OP_SET_GE:
value = sign_extend(value, def->size);
+ if (insn->opcode == OP_SET_GE)
+ value -= 1;
if (bits & sign_bit(def->size))
break;
if (value < 0)
@@ -1344,16 +1362,20 @@ static int simplify_compare_constant(struct instruction *insn, long long value)
if (bits >= value)
return replace_with_value(insn, 1);
break;
+ case OP_SET_LT:
+ value -= 1;
case OP_SET_LE:
- value = sign_extend(value, def->size);
if (bits & sign_bit(def->size)) {
+ value = sign_extend(value, def->size);
if (value >= -1)
return replace_with_value(insn, 1);
}
break;
+ case OP_SET_GE:
+ value -= 1;
case OP_SET_GT:
- value = sign_extend(value, def->size);
if (bits & sign_bit(def->size)) {
+ value = sign_extend(value, def->size);
if (value >= -1)
return replace_with_value(insn, 0);
}
@@ -1396,6 +1418,20 @@ static int simplify_compare_constant(struct instruction *insn, long long value)
break;
}
break;
+ case OP_TRUNC:
+ osize = def->orig_type->bit_size;
+ switch (insn->opcode) {
+ case OP_SET_EQ: case OP_SET_NE:
+ if (one_use(def->target)) {
+ insn->itype = def->orig_type;
+ def->type = def->orig_type;
+ def->size = osize;
+ def->src2 = value_pseudo(bits);
+ return replace_opcode(def, OP_AND);
+ }
+ break;
+ }
+ break;
case OP_ZEXT:
osize = def->orig_type->bit_size;
bits = bits_mask(osize);
@@ -1902,6 +1938,17 @@ static int simplify_and_one_side(struct instruction *insn, pseudo_t *p1, pseudo_
if (def->src1 == defr->src1 && def->src2 == defr->src2)
return replace_with_value(insn, 0);
}
+ if (def->opcode == OP_SET_GE && is_zero(def->src2)) {
+ switch (DEF_OPCODE(defr, *p2)) {
+ case OP_SET_LE:
+ if (!is_positive(defr->src2, defr->itype->bit_size))
+ break;
+ // (x >= 0) && (x <= C) --> (x u<= C)
+ insn->itype = defr->itype;
+ replace_binop(insn, OP_SET_BE, &insn->src1, defr->src1, &insn->src2, defr->src2);
+ return REPEAT_CSE;
+ }
+ }
break;
case OP_OR:
if (DEF_OPCODE(defr, *p2) == OP_OR) {
@@ -2292,6 +2339,21 @@ static int simplify_cast(struct instruction *insn)
return replace_pseudo(insn, &insn->src1, def->src1);
}
break;
+ case OP_NOT:
+ switch (insn->opcode) {
+ case OP_TRUNC:
+ if (one_use(src)) {
+ // TRUNC(NOT(x)) --> NOT(TRUNC(x))
+ insn->opcode = OP_NOT;
+ def->orig_type = def->type;
+ def->opcode = OP_TRUNC;
+ def->type = insn->type;
+ def->size = insn->size;
+ return REPEAT_CSE;
+ }
+ break;
+ }
+ break;
case OP_OR:
switch (insn->opcode) {
case OP_TRUNC:
@@ -2542,23 +2604,12 @@ static int simplify_branch(struct instruction *insn)
pseudo_t cond = insn->cond;
/* Constant conditional */
- if (constant(cond)) {
- insert_branch(insn->bb, insn, cond->value ? insn->bb_true : insn->bb_false);
- return REPEAT_CSE;
- }
+ if (constant(cond))
+ return convert_to_jump(insn, cond->value ? insn->bb_true : insn->bb_false);
/* Same target? */
- if (insn->bb_true == insn->bb_false) {
- struct basic_block *bb = insn->bb;
- struct basic_block *target = insn->bb_false;
- remove_bb_from_list(&target->parents, bb, 1);
- remove_bb_from_list(&bb->children, target, 1);
- insn->bb_false = NULL;
- kill_use(&insn->cond);
- insn->cond = NULL;
- insn->opcode = OP_BR;
- return REPEAT_CSE|REPEAT_CFG_CLEANUP;
- }
+ if (insn->bb_true == insn->bb_false)
+ return convert_to_jump(insn, insn->bb_true);
/* Conditional on a SETNE $0 or SETEQ $0 */
if (cond->type == PSEUDO_REG) {
@@ -2574,14 +2625,10 @@ static int simplify_branch(struct instruction *insn)
if (constant(def->src2) && constant(def->src3)) {
long long val1 = def->src2->value;
long long val2 = def->src3->value;
- if (!val1 && !val2) {
- insert_branch(insn->bb, insn, insn->bb_false);
- return REPEAT_CSE;
- }
- if (val1 && val2) {
- insert_branch(insn->bb, insn, insn->bb_true);
- return REPEAT_CSE;
- }
+ if (!val1 && !val2)
+ return convert_to_jump(insn, insn->bb_false);
+ if (val1 && val2)
+ return convert_to_jump(insn, insn->bb_true);
if (val2) {
struct basic_block *tmp = insn->bb_true;
insn->bb_true = insn->bb_false;
@@ -2617,8 +2664,7 @@ static int simplify_switch(struct instruction *insn)
return 0;
found:
- insert_branch(insn->bb, insn, jmp->target);
- return REPEAT_CSE;
+ return convert_to_jump(insn, jmp->target);
}
static struct basic_block *is_label(pseudo_t pseudo)
@@ -2655,7 +2701,7 @@ static int simplify_cgoto(struct instruction *insn)
continue;
remove_bb_from_list(&jmp->target->parents, bb, 1);
remove_bb_from_list(&bb->children, jmp->target, 1);
- MARK_CURRENT_DELETED(jmp);
+ DELETE_CURRENT_PTR(jmp);
} END_FOR_EACH_PTR(jmp);
kill_use(&insn->src);
insn->opcode = OP_BR;
generated by cgit 1.2.3-korg (git 2.43.0) at 2026-03-01 17:08:55 +0000