Add line numbers to JIT stack traces. (#667)

src/scripting/vm/jit.cpp

@@ -98,6 +98,8 @@ asmjit::CCFunc *JitCompiler::Codegen()
 {
 	Setup();
 
+	LatestLine = { 0, (ptrdiff_t)0, -1, {} };
+
 	pc = sfunc->Code;
 	auto end = pc + sfunc->CodeSize;
 	while (pc != end)
@@ -105,10 +107,21 @@ asmjit::CCFunc *JitCompiler::Codegen()
 		int i = (int)(ptrdiff_t)(pc - sfunc->Code);
 		op = pc->op;
 
+		int curLine = sfunc->PCToLine(pc);
+		auto label = cc.newLabel ();
+		cc.bind (label);
+		LatestLine.Label = label;
+		if (curLine != LatestLine.LineNumber)
+		{
+			LatestLine.LineNumber = curLine;
+			LatestLine.VMInstructionIndex = i;
+			LineInfo.Push (LatestLine);
+		}
+
 		if (op != OP_PARAM && op != OP_PARAMI && op != OP_VTBL)
 		{
 			FString lineinfo;
-			lineinfo.Format("; line %d: %02x%02x%02x%02x %s", sfunc->PCToLine(pc), pc->op, pc->a, pc->b, pc->c, OpNames[op]);
+			lineinfo.Format("; line %d: %02x%02x%02x%02x %s", curLine, pc->op, pc->a, pc->b, pc->c, OpNames[op]);
 			cc.comment("", 0);
 			cc.comment(lineinfo.GetChars(), lineinfo.Len());
 		}
@@ -125,6 +138,21 @@ asmjit::CCFunc *JitCompiler::Codegen()
 	cc.endFunc();
 	cc.finalize();
 
+	auto code = cc.getCode ();
+	for (unsigned int j = 0; j < LineInfo.Size (); j++)
+	{
+		auto info = LineInfo[j];
+
+		if (!code->isLabelValid (info.Label))
+		{
+			continue;
+		}
+
+		info.InstructionIndex = code->getLabelOffset (info.Label);
+
+		LineInfo[j] = info;
+	}
+
 	return func;
 }
 

src/scripting/vm/jit_runtime.cpp

@@ -15,6 +15,7 @@ struct JitFuncInfo
 {
 	FString name;
 	FString filename;
+	TArray<JitLineInfo> LineInfo;
 	void *start;
 	void *end;
 };
@@ -301,7 +302,7 @@ void *AddJitFunction(asmjit::CodeHolder* code, JitCompiler *compiler)
 	if (result == 0)
 		I_Error("RtlAddFunctionTable failed");
 
-	JitDebugInfo.Push({ compiler->GetScriptFunction()->PrintableName, compiler->GetScriptFunction()->SourceFileName, startaddr, endaddr });
+	JitDebugInfo.Push({ compiler->GetScriptFunction()->PrintableName, compiler->GetScriptFunction()->SourceFileName, compiler->LineInfo, startaddr, endaddr });
 #endif
 
 	return p;
@@ -957,6 +958,20 @@ public:
 };
 #endif
 
+int JITPCToLine(uint8_t *pc, const JitFuncInfo *info)
+{
+	int PCIndex = int(pc - ((uint8_t *) (info->start)));
+	if (info->LineInfo.Size () == 1) return info->LineInfo[0].LineNumber;
+	for (unsigned i = 1; i < info->LineInfo.Size (); i++)
+	{
+		if (info->LineInfo[i].InstructionIndex >= PCIndex)
+		{
+			return info->LineInfo[i - 1].LineNumber;
+		}
+	}
+	return -1;
+}
+
 FString JitGetStackFrameName(NativeSymbolResolver *nativeSymbols, void *pc)
 {
 	for (unsigned int i = 0; i < JitDebugInfo.Size(); i++)
@@ -964,12 +979,7 @@ FString JitGetStackFrameName(NativeSymbolResolver *nativeSymbols, void *pc)
 		const auto &info = JitDebugInfo[i];
 		if (pc >= info.start && pc < info.end)
 		{
-			int line = -1;
+			int line = JITPCToLine ((uint8_t *)pc, &info);
-			/*for (unsigned int j = 0; j < info.lines.Size(); j++)
-			{
-				if (info.lines[j].pc <= pc)
-					line = info.lines[j].line;
-			}*/
 
 			FString s;
 

src/scripting/vm/jitintern.h

@@ -25,6 +25,14 @@ extern int VMCalls[10];
 #define ABCs			(pc[0].i24)
 #define JMPOFS(x)		((x)->i24)
 
+struct JitLineInfo
+{
+	uint16_t VMInstructionIndex;
+	ptrdiff_t InstructionIndex;
+	int32_t LineNumber;
+	asmjit::Label Label;
+};
+
 class JitCompiler
 {
 public:
@@ -33,6 +41,8 @@ public:
 	asmjit::CCFunc *Codegen();
 	VMScriptFunction *GetScriptFunction() { return sfunc; }
 
+	TArray<JitLineInfo> LineInfo;
+
 private:
 	// Declare EmitXX functions for the opcodes:
 	#define xx(op, name, mode, alt, kreg, ktype)	void Emit##op();
@@ -260,6 +270,8 @@ private:
 	TArray<asmjit::X86Gp> regA;
 	TArray<asmjit::X86Gp> regS;
 
+	JitLineInfo LatestLine;
+
 	struct OpcodeLabel
 	{
 		asmjit::CBNode *cursor = nullptr;