The goal is double:
1) be able to do the NOT operation on the smaller type
2) more importantly, give the opportunity to the TRUNC to
cancel with a previous ZEXT if there is one.
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@xxxxxxxxx>
---
simplify.c | 15 +++++++++++++++
validation/optim/trunc-not0.c | 1 -
2 files changed, 15 insertions(+), 1 deletion(-)
diff --git a/simplify.c b/simplify.c
index 9e3514d838a9..b2311d397b23 100644
--- a/simplify.c
+++ b/simplify.c
@@ -2288,6 +2288,21 @@ 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))
+ break;
+
+ // 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;
case OP_OR:
switch (insn->opcode) {
case OP_TRUNC:
diff --git a/validation/optim/trunc-not0.c b/validation/optim/trunc-not0.c
index febed165b0c4..882b446d9197 100644
--- a/validation/optim/trunc-not0.c
+++ b/validation/optim/trunc-not0.c
@@ -14,7 +14,6 @@ static _Bool ubar(uint64 a) { return (~(uint32) ~a) == (uint32)a; }
/*
* check-name: trunc-not0
* check-command: test-linearize -Wno-decl $file
- * check-known-to-fail
*
* check-output-ignore
* check-output-returns: 1
--
2.31.1
