Core: Interpreter Implementation of PS2's floating point unit specification.

This commit implements software floating points support in PCSX2's interpreters.

This work is a combination or several efforts and researches done prior.

Credits:

- https://www.gregorygaines.com/blog/emulating-ps2-floating-point-nums-ieee-754-diffs-part-1/

- https://github.com/GitHubProUser67/MultiServer3/tree/main/BackendServices/PS2FloatLibrary

- https://github.com/Goatman13/pcsx2/tree/accurate_int_add_sub

- PCSX2 Team for their help and support in this massive journey.

Author: GitHubProUser67

common/BitUtils.h

@@ -28,6 +28,19 @@ static inline int _BitScanReverse(unsigned long* const Index, const unsigned lon
 
 namespace Common
 {
+	static constexpr s8 msb[256] = {
+		-1, 0, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
+		5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+		6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+		6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+		7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+		7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+		7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+		7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7};
+
+	static constexpr s32 normalizeAmounts[] = {
+		0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 8, 8, 8, 8, 8, 8, 8, 16, 16, 16, 16, 16, 16, 16, 16, 24, 24, 24, 24, 24, 24, 24};
+
 	template <typename T>
 	static constexpr __fi bool IsAligned(T value, unsigned int alignment)
 	{
@@ -71,6 +84,11 @@ namespace Common
 		return Common::AlignUpPow2(size, __pagesize);
 	}
 
+	__fi static s32 BitScanReverse8(s32 b)
+	{
+		return msb[b];
+	}
+
 	__fi static u32 CountLeadingSignBits(s32 n)
 	{
 		// If the sign bit is 1, we invert the bits to 0 for count-leading-zero.

pcsx2-qt/Settings/AdvancedSettingsWidget.cpp

@@ -48,6 +48,16 @@ AdvancedSettingsWidget::AdvancedSettingsWidget(SettingsWindow* dialog, QWidget*
 	connect(m_ui.vu0ClampMode, QOverload<int>::of(&QComboBox::currentIndexChanged), [this](int index) { setClampingMode(0, index); });
 	connect(m_ui.vu1ClampMode, QOverload<int>::of(&QComboBox::currentIndexChanged), [this](int index) { setClampingMode(1, index); });
 
+	SettingWidgetBinder::BindWidgetToBoolSetting(sif, m_ui.eeSoftAddSub, "EmuCore/CPU/Recompiler", "fpuSoftAddSub", false);
+	SettingWidgetBinder::BindWidgetToBoolSetting(sif, m_ui.eeSoftMulDiv, "EmuCore/CPU/Recompiler", "fpuSoftMulDiv", false);
+	SettingWidgetBinder::BindWidgetToBoolSetting(sif, m_ui.eeSoftSqrt, "EmuCore/CPU/Recompiler", "fpuSoftSqrt", false);
+	SettingWidgetBinder::BindWidgetToBoolSetting(sif, m_ui.vu0SoftAddSub, "EmuCore/CPU/Recompiler", "vu0SoftAddSub", false);
+	SettingWidgetBinder::BindWidgetToBoolSetting(sif, m_ui.vu0SoftMulDiv, "EmuCore/CPU/Recompiler", "vu0SoftMulDiv", false);
+	SettingWidgetBinder::BindWidgetToBoolSetting(sif, m_ui.vu0SoftSqrt, "EmuCore/CPU/Recompiler", "vu0SoftSqrt", false);
+	SettingWidgetBinder::BindWidgetToBoolSetting(sif, m_ui.vu1SoftAddSub, "EmuCore/CPU/Recompiler", "vu1SoftAddSub", false);
+	SettingWidgetBinder::BindWidgetToBoolSetting(sif, m_ui.vu1SoftMulDiv, "EmuCore/CPU/Recompiler", "vu1SoftMulDiv", false);
+	SettingWidgetBinder::BindWidgetToBoolSetting(sif, m_ui.vu1SoftSqrt, "EmuCore/CPU/Recompiler", "vu1SoftSqrt", false);
+
 	SettingWidgetBinder::BindWidgetToBoolSetting(sif, m_ui.iopRecompiler, "EmuCore/CPU/Recompiler", "EnableIOP", true);
 
 	SettingWidgetBinder::BindWidgetToBoolSetting(sif, m_ui.gameFixes, "EmuCore", "EnableGameFixes", true);