DebugTools: Add noreturn heuristic

PCSX2 · Feb 28, 2024 · 4919f9b · 4919f9b
1 parent b07b56f
commit 4919f9b
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Showing 5 changed files with 48 additions and 7 deletions.
diff --git a/pcsx2-qt/Debugger/DisassemblyWidget.cpp b/pcsx2-qt/Debugger/DisassemblyWidget.cpp
@@ -745,19 +745,33 @@ inline QString DisassemblyWidget::DisassemblyStringFromAddress(u32 address, QFon
 	const bool isConditionalMet = line.info.conditionMet;
 	const bool isCurrentPC = m_cpu->getPC() == address;
 
-	const std::string addressSymbol = m_cpu->GetSymbolMap().GetLabelName(address);
+	bool isFunctionNoReturn = false;
 
+	const std::string addressSymbol = m_cpu->GetSymbolMap().GetLabelName(address);
+	if(m_cpu->GetSymbolMap().GetFunctionStart(address) == address)
+	{
+		isFunctionNoReturn = m_cpu->GetSymbolMap().GetFunctionNoReturn(address);
+	}
 	const auto demangler = demangler::CDemangler::createGcc();
 	const bool showOpcode = m_showInstructionOpcode && m_cpu->isAlive();
 
 	QString lineString;
 	if (showOpcode)
 	{
-		lineString = QString("  %1 %2  %3 %4  %5 %6");
+		lineString = QString(" %1 %2 %3  %4 %5  %6 %7");
+	}
+	else
+	{
+		lineString = QString(" %1 %2  %3 %4  %5 %6");
+	}
+
+	if(isFunctionNoReturn)
+	{
+		lineString = lineString.arg("NR");
 	}
 	else
 	{
-		lineString = QString("  %1  %2 %3  %4 %5");
+		lineString = lineString.arg("  ");
 	}
 
 	if (addressSymbol.empty()) // The address wont have symbol text if it's the start of a function for example
@@ -780,7 +794,7 @@ inline QString DisassemblyWidget::DisassemblyStringFromAddress(u32 address, QFon
 			symbolString = QString::fromStdString(addressSymbol);
 		}
 
-		lineString = lineString.arg(metric.elidedText(symbolString, Qt::ElideRight, (selected ? 32.0f : 7.5f) * font.pointSize()));
+		lineString = lineString.arg(metric.elidedText(symbolString, Qt::ElideRight, (selected ? 32 : 7) * font.pointSize()));
 	}
 
 	if (showOpcode)

diff --git a/pcsx2/DebugTools/MIPSAnalyst.cpp b/pcsx2/DebugTools/MIPSAnalyst.cpp
@@ -190,6 +190,7 @@ namespace MIPSAnalyst
 		bool looking = false;
 		bool end = false;
 		bool isStraightLeaf = true;
+		bool suspectedNoReturn = false;
 
 		functions.clear();
 
@@ -219,6 +220,16 @@ namespace MIPSAnalyst
 				if (target > furthestBranch) {
 					furthestBranch = target;
 				}
+
+				// beq $zero, $zero, xyz
+				if ((op >> 16) == 0x1000)
+				{
+					// If it's backwards, and there's no other branch passing it, treat as noreturn
+					if(target < addr && furthestBranch < addr)
+					{
+						end = suspectedNoReturn = true;
+					}
+				}
 			} else if ((op & 0xFC000000) == 0x08000000) {
 				u32 sureTarget = GetJumpTarget(addr);
 				// Check for a tail call.  Might not even have a jr ra.
@@ -286,11 +297,13 @@ namespace MIPSAnalyst
 
 				currentFunction.end = addr + 4;
 				currentFunction.isStraightLeaf = isStraightLeaf;
+				currentFunction.suspectedNoReturn = suspectedNoReturn;
 				functions.push_back(currentFunction);
 				furthestBranch = 0;
 				addr += 4;
 				looking = false;
 				end = false;
+				suspectedNoReturn = false;
 				isStraightLeaf = true;
 
 				currentFunction.start = addr+4;
@@ -304,7 +317,7 @@ namespace MIPSAnalyst
 			iter->size = iter->end - iter->start + 4;
 			if (insertSymbols) {
 				char temp[256];
-				map.AddFunction(DefaultFunctionName(temp, iter->start), iter->start, iter->end - iter->start + 4);
+				map.AddFunction(DefaultFunctionName(temp, iter->start), iter->start, iter->end - iter->start + 4, iter->suspectedNoReturn);
 			}
 		}
 	}

diff --git a/pcsx2/DebugTools/MIPSAnalyst.h b/pcsx2/DebugTools/MIPSAnalyst.h
@@ -25,6 +25,7 @@ namespace MIPSAnalyst
 		u32 size;
 		bool isStraightLeaf;
 		bool hasHash;
+		bool suspectedNoReturn;
 		bool usesVFPU;
 		char name[64];
 	};

diff --git a/pcsx2/DebugTools/SymbolMap.cpp b/pcsx2/DebugTools/SymbolMap.cpp
@@ -241,7 +241,7 @@ std::vector<SymbolEntry> SymbolMap::GetAllSymbols(SymbolType symmask) const
 	return result;
 }
 
-void SymbolMap::AddFunction(const std::string& name, u32 address, u32 size)
+void SymbolMap::AddFunction(const std::string& name, u32 address, u32 size, bool noReturn)
 {
 	std::lock_guard<std::recursive_mutex> guard(m_lock);
 
@@ -258,6 +258,7 @@ void SymbolMap::AddFunction(const std::string& name, u32 address, u32 size)
 		func.size = size;
 		func.index = (int)functions.size();
 		func.name = name;
+		func.noReturn = noReturn;
 		functions[address] = func;
 
 		functions.insert(std::make_pair(address, func));
@@ -321,6 +322,16 @@ int SymbolMap::GetFunctionNum(u32 address) const
 	return it->second.index;
 }
 
+bool SymbolMap::GetFunctionNoReturn(u32 address) const
+{
+	std::lock_guard<std::recursive_mutex> guard(m_lock);
+	auto it = functions.find(address);
+	if (it == functions.end())
+		return false;
+
+	return it->second.noReturn;
+}
+
 void SymbolMap::AssignFunctionIndices()
 {
 	std::lock_guard<std::recursive_mutex> guard(m_lock);

diff --git a/pcsx2/DebugTools/SymbolMap.h b/pcsx2/DebugTools/SymbolMap.h
@@ -72,9 +72,10 @@ class SymbolMap
 	std::string GetDescription(unsigned int address) const;
 	std::vector<SymbolEntry> GetAllSymbols(SymbolType symmask) const;
 
-	void AddFunction(const std::string& name, u32 address, u32 size);
+	void AddFunction(const std::string& name, u32 address, u32 size, bool noReturn = false);
 	u32 GetFunctionStart(u32 address) const;
 	int GetFunctionNum(u32 address) const;
+	bool GetFunctionNoReturn(u32 address) const;
 	u32 GetFunctionSize(u32 startAddress) const;
 	bool SetFunctionSize(u32 startAddress, u32 newSize);
 	bool RemoveFunction(u32 startAddress);
@@ -113,6 +114,7 @@ class SymbolMap
 		u32 size;
 		int index;
 		std::string name;
+		bool noReturn;
 	};
 
 	struct LabelEntry