Currently, simplify_unop() can only handle the simplification of
-(-x) and ~(~x).
Prepare it to handle more cases.
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@xxxxxxxxx>
---
simplify.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/simplify.c b/simplify.c
index 6caf6cbcf918..2750a90512b8 100644
--- a/simplify.c
+++ b/simplify.c
@@ -1451,21 +1451,27 @@ static int simplify_constant_unop(struct instruction *insn)
static int simplify_unop(struct instruction *insn)
{
+ pseudo_t src = insn->src;
+
if (dead_insn(insn, &insn->src1, NULL, NULL))
return REPEAT_CSE;
- if (constant(insn->src1))
+ if (constant(src))
return simplify_constant_unop(insn);
switch (insn->opcode) {
struct instruction *def;
case OP_NOT:
- if (DEF_OPCODE(def, insn->src) == OP_NOT)
+ switch (DEF_OPCODE(def, src)) {
+ case OP_NOT: // ~(~x) --> x
return replace_with_pseudo(insn, def->src);
+ }
break;
case OP_NEG:
- if (DEF_OPCODE(def, insn->src) == OP_NEG)
+ switch (DEF_OPCODE(def, src)) {
+ case OP_NEG: // -(-x) --> x
return replace_with_pseudo(insn, def->src);
+ }
break;
default:
return 0;
--
2.28.0
