Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@xxxxxxxxx> --- simplify.c | 8 +++++++- validation/optim/bool-not-zero.c | 8 ++++++++ 2 files changed, 15 insertions(+), 1 deletion(-) diff --git a/simplify.c b/simplify.c index e4ccb6c5f..775c1e2dd 100644 --- a/simplify.c +++ b/simplify.c @@ -467,6 +467,13 @@ static int simplify_constant_rightside(struct instruction *insn) return replace_with_pseudo(insn, insn->src2); goto case_neutral_zero; + case OP_XOR: + if ((value & bits) == bits) { + insn->opcode = OP_NOT; + return REPEAT_CSE; + } + goto case_neutral_zero; + case OP_SUB: if (value) { insn->opcode = OP_ADD; @@ -475,7 +482,6 @@ static int simplify_constant_rightside(struct instruction *insn) } /* Fall through */ case OP_ADD: - case OP_XOR: case OP_SHL: case OP_LSR: case_neutral_zero: diff --git a/validation/optim/bool-not-zero.c b/validation/optim/bool-not-zero.c index ce74705e8..189fe3311 100644 --- a/validation/optim/bool-not-zero.c +++ b/validation/optim/bool-not-zero.c @@ -1,5 +1,6 @@ int or_not0(int a) { return a | ~0; } int and_not0(int a) { return a & ~0; } +int xor_not0(int a) { return a ^ ~0; } /* * check-name: bool-not-zero @@ -18,5 +19,12 @@ and_not0: ret.32 %arg1 +xor_not0: +.L4: + <entry-point> + not.32 %r8 <- %arg1 + ret.32 %r8 + + * check-output-end */ -- 2.12.0 -- To unsubscribe from this list: send the line "unsubscribe linux-sparse" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html