From d699d32f47833cfab959a810dad48774c021c677 Mon Sep 17 00:00:00 2001 From: Xi Ruoyao Date: Fri, 4 Nov 2022 01:35:25 +0800 Subject: LoongArch: fix signed overflow in loongarch_emit_int_compare Signed overflow is an undefined behavior, so we need to prevent it from happening, instead of "checking" the result. gcc/ChangeLog: * config/loongarch/loongarch.cc (loongarch_emit_int_compare): Avoid signed overflow. --- gcc/config/loongarch/loongarch.cc | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'gcc') diff --git a/gcc/config/loongarch/loongarch.cc b/gcc/config/loongarch/loongarch.cc index f54c233..8d5d8d9 100644 --- a/gcc/config/loongarch/loongarch.cc +++ b/gcc/config/loongarch/loongarch.cc @@ -4178,10 +4178,13 @@ loongarch_emit_int_compare (enum rtx_code *code, rtx *op0, rtx *op1) if (!increment && !decrement) continue; + if ((increment && rhs == HOST_WIDE_INT_MAX) + || (decrement && rhs == HOST_WIDE_INT_MIN)) + break; + new_rhs = rhs + (increment ? 1 : -1); if (loongarch_integer_cost (new_rhs) - < loongarch_integer_cost (rhs) - && (rhs < 0) == (new_rhs < 0)) + < loongarch_integer_cost (rhs)) { *op1 = GEN_INT (new_rhs); *code = mag_comparisons[i][increment]; -- cgit v1.1