Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@xxxxxxxxx> --- simplify.c | 16 +++++++++++++++- validation/optim/simplify-sub-neg.c | 1 - 2 files changed, 15 insertions(+), 2 deletions(-) diff --git a/simplify.c b/simplify.c index 929a177631e5..fa7e1679d7ac 100644 --- a/simplify.c +++ b/simplify.c @@ -1358,6 +1358,20 @@ static int simplify_associative_binop(struct instruction *insn) return REPEAT_CSE; } +static int simplify_sub(struct instruction *insn) +{ + pseudo_t src2 = insn->src2; + struct instruction *def; + + switch (DEF_OPCODE(def, src2)) { + case OP_NEG: // (x - -y) --> (x + y) + insn->opcode = OP_ADD; + return replace_pseudo(insn, &insn->src2, def->src); + } + + return 0; +} + static int simplify_constant_unop(struct instruction *insn) { long long val = insn->src1->value; @@ -1818,8 +1832,8 @@ int simplify_instruction(struct instruction *insn) } switch (insn->opcode) { + case OP_SUB: return simplify_sub(insn); case OP_ADD: - case OP_SUB: case OP_MUL: case OP_AND: case OP_OR: diff --git a/validation/optim/simplify-sub-neg.c b/validation/optim/simplify-sub-neg.c index b6fcc2baabec..49be847cca7d 100644 --- a/validation/optim/simplify-sub-neg.c +++ b/validation/optim/simplify-sub-neg.c @@ -3,7 +3,6 @@ int sub_neg(int x, int y) { return x - -y; } /* * check-name: simplify-sub-neg * check-command: test-linearize -Wno-decl $file - * check-known-to-fail * * check-output-ignore * check-output-contains: add\\..*%arg., %arg. -- 2.28.0