From 54e34d6a903a34d19a0e383d99593b03e7ee3673 Mon Sep 17 00:00:00 2001
From: Gary Talent <gary@drinkingtea.net>
Date: Thu, 17 Mar 2022 03:53:46 -0500
Subject: [PATCH] [ox/std] Fix MaxValue for signed ints

(synced from b43f5e3b98499331f159962d1b697767b4a42f09)
---
 src/ox/std/bit.cpp | 9 +++++++++
 src/ox/std/bit.hpp | 8 +++++---
 2 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/src/ox/std/bit.cpp b/src/ox/std/bit.cpp
index 6f4a60a87..5af893f1b 100644
--- a/src/ox/std/bit.cpp
+++ b/src/ox/std/bit.cpp
@@ -12,3 +12,12 @@ static_assert(ox::onMask<int>(1) == 0b0001);
 static_assert(ox::onMask<int>(2) == 0b0011);
 static_assert(ox::onMask<int>(3) == 0b0111);
 static_assert(ox::onMask<int>(4) == 0b1111);
+
+static_assert(ox::MaxValue<int8_t>   ==                   127);
+static_assert(ox::MaxValue<int16_t>  ==                 32767);
+static_assert(ox::MaxValue<int32_t>  ==            2147483647);
+static_assert(ox::MaxValue<int64_t>  ==   9223372036854775807);
+static_assert(ox::MaxValue<uint8_t>  ==                   255);
+static_assert(ox::MaxValue<uint16_t> ==                 65535);
+static_assert(ox::MaxValue<uint32_t> ==            4294967295);
+static_assert(ox::MaxValue<uint64_t> == 18446744073709551615u);
diff --git a/src/ox/std/bit.hpp b/src/ox/std/bit.hpp
index 61915217b..23cb75a8f 100644
--- a/src/ox/std/bit.hpp
+++ b/src/ox/std/bit.hpp
@@ -38,13 +38,15 @@ constexpr typename enable_if<sizeof(To) == sizeof(From), To>::type cbit_cast(Fro
 }
 
 template<typename T>
-[[nodiscard]] constexpr T rotl(T i, int shift) noexcept {
+[[nodiscard]]
+constexpr T rotl(T i, int shift) noexcept {
 	constexpr auto bits = sizeof(i) * 8;
 	return (i << static_cast<T>(shift)) | (i >> (bits - static_cast<T>(shift)));
 }
 
 template<typename T, typename B = int>
-[[nodiscard]] constexpr T onMask(B bits = sizeof(T) << 3 /* *8 */) noexcept {
+[[nodiscard]]
+constexpr T onMask(B bits = sizeof(T) << 3 /* *8 */) noexcept {
 	T out = T(0);
 	for (B i = 0; i < bits; i++) {
 		out |= static_cast<T>(1) << i;
@@ -53,6 +55,6 @@ template<typename T, typename B = int>
 }
 
 template<typename T>
-constexpr auto MaxValue = onMask<T>();
+constexpr auto MaxValue = onMask<T>(is_signed_v<T> ? sizeof(T) * 8 - 1 : sizeof(T) * 8);
 
 }