From d0274f412a67ca7718c35cab2c57db58a6a56022 Mon Sep 17 00:00:00 2001
From: Lioncash <mathew1800@gmail.com>
Date: Tue, 17 Jul 2018 14:39:07 -0400
Subject: [PATCH] safe_ops: Avoid signed overflow in Negate()

Negation of values such as -9223372036854775808 can't be represented in
signed equivalents (such as long long), leading to signed overflow.
Therefore, we can just invert bits and add 1 to perform this behavior
with unsigned arithmetic.
---
 src/common/safe_ops.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/common/safe_ops.h b/src/common/safe_ops.h
index bc6d7b88..eb833ebb 100644
--- a/src/common/safe_ops.h
+++ b/src/common/safe_ops.h
@@ -103,7 +103,7 @@ T ArithmeticShiftRightDouble(T top, T bottom, int shift_amount) {
 
 template<typename T>
 T Negate(T value) {
-    return static_cast<T>(-static_cast<std::make_signed_t<T>>(value));
+    return static_cast<T>(~static_cast<std::uintmax_t>(value) + 1);
 }
 
 } // namespace Dynarmic::Safe