Add line numbers to JIT stack traces.

Doom2fan · Dec 18, 2018 · e885376 · e885376
1 parent 27ecae2
commit e885376
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Showing 3 changed files with 61 additions and 2 deletions.
diff --git a/src/scripting/vm/jit.cpp b/src/scripting/vm/jit.cpp
@@ -98,17 +98,33 @@ asmjit::CCFunc *JitCompiler::Codegen()
 {
 	Setup();
 
+	LatestLine = { 0, (ptrdiff_t)0, -1, {} };
+
 	pc = sfunc->Code;
 	auto end = pc + sfunc->CodeSize;
 	while (pc != end)
 	{
 		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)
+		{
+			FString linfo;
+			linfo.Format ("; line %d ========== DEBUG ==========", curLine);
+			cc.comment (linfo.GetChars (), linfo.Len ());
+			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 +141,21 @@ 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;
 }
 

diff --git a/src/scripting/vm/jit_runtime.cpp b/src/scripting/vm/jit_runtime.cpp
@@ -10,6 +10,7 @@ struct JitFuncInfo
 {
 	FString name;
 	FString filename;
+	TArray<JitLineInfo> LineInfo;
 	void *start;
 	void *end;
 };
@@ -293,7 +294,7 @@ void *AddJitFunction(asmjit::CodeHolder* code, JitCompiler *compiler)
 		I_Error("RtlAddFunctionTable failed");
 #endif
 
-	JitDebugInfo.Push({ compiler->GetScriptFunction()->PrintableName, compiler->GetScriptFunction()->SourceFileName, startaddr, endaddr });
+	JitDebugInfo.Push({ compiler->GetScriptFunction()->PrintableName, compiler->GetScriptFunction()->SourceFileName, compiler->LineInfo, startaddr, endaddr });
 
 	return p;
 }
@@ -840,6 +841,20 @@ static int CaptureStackTrace(int max_frames, void **out_frames)
 #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(void *pc)
 {
 	FString s;
@@ -850,6 +865,7 @@ FString JitGetStackFrameName(void *pc)
 		if (pc >= info.start && pc < info.end)
 		{
 			int line = -1;
+			line = JITPCToLine ((uint8_t *)pc, &info);
 			/*for (unsigned int j = 0; j < info.lines.Size(); j++)
 			{
 				if (info.lines[j].pc <= pc)

diff --git a/src/scripting/vm/jitintern.h b/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 @@ class JitCompiler
 	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 @@ class JitCompiler
 	TArray<asmjit::X86Gp> regA;
 	TArray<asmjit::X86Gp> regS;
 
+	JitLineInfo LatestLine;
+
 	struct OpcodeLabel
 	{
 		asmjit::CBNode *cursor = nullptr;