DebugInfo: debug types

src/backend/ir/debug_info.cpp

@@ -1,6 +1,15 @@
 #include "ir/debug_info.h"
 
 namespace rat {
+	DebugType* DebugInfo::makeType(DebugType::Kind kind, String name, U32 size) {
+		types.push_back(std::make_unique<DebugType>());
+		DebugType* t = types.back().get();
+		t->kind = kind;
+		t->name = std::move(name);
+		t->size = size;
+		return t;
+	}
+
 	// consecutive nodes mostly share a location, reuse the last entry then
 	U32 DebugBody::addLoc(SrcLoc src) {
 		const DebugLoc& last = locs.back();

src/backend/ir/debug_info.h

@@ -5,28 +5,88 @@
 #include "core.h"
 
 namespace rat {
+	struct AllocNode;
+
 	struct SrcLoc {
 		U32 file = 0; // DebugInfo::files
 		U32 line = 0;
 		U32 col = 0;
 	};
 
+	struct DebugType {
+		enum class Kind : U8 {
+			Signed,
+			Unsigned,
+			SignedChar,
+			UnsignedChar,
+			Bool,
+			Float,
+			ComplexFloat,
+			Pointer,
+			Struct,
+			Union,
+			Array,
+			Function,
+			Typedef,
+			Enum,
+			Const,
+			Volatile
+		};
+		struct Member {
+			String name;
+			DebugType* type;
+			U32 offset;			 // bytes
+			U32 bitSize = 0; // 0 = not a bitfield
+			U32 bitOffset = 0;
+		};
+
+		Kind kind;
+		String name;
+		U32 size = 0;
+		DebugType* elem = nullptr; // pointee, element, return, aliased or underlying type, null = void
+		U64 count = 0;						 // array length, 0 = unknown
+		List<Member> members;
+		List<DebugType*> params;
+		B32 variadic = false;
+		B32 incomplete = false; // declared struct without a body
+		List<Pair<String, I64>> enumerators;
+		SrcLoc decl; // typedef and enum
+	};
+
+	// a source variable, shared by every copy of its function's code
+	struct DebugVar {
+		String name;
+		DebugType* type;
+		SrcLoc decl;
+		String symbol; // static storage, else empty
+		B32 isParam = false;
+	};
+
 	// a source function, outlives its IR function so inlined copies can still name it
 	struct DebugFunc {
 		String name;
 		SrcLoc decl;
+		DebugType* ret = nullptr;
 		B32 external = false;
 		B32 variadic = false;
+		List<UniquePtr<DebugVar>> vars; // params first
 	};
 
 	struct DebugLoc {
 		SrcLoc src;
 	};
 
+	// one copy of a variable in a function's code
+	struct DebugVarInst {
+		const DebugVar* var;
+		AllocNode* slot = nullptr; // frame storage
+	};
+
 	// debug state of one IR function
 	struct DebugBody {
 		DebugFunc* func;
 		List<DebugLoc> locs = List<DebugLoc>(1); // 0 = no location
+		List<DebugVarInst> vars;
 
 		U32 addLoc(SrcLoc src);
 	};
@@ -35,7 +95,11 @@ namespace rat {
 		String producer;
 		String compDir;
 		List<String> files; // files[0] is the primary source
+		List<DebugVar> globals;
 		List<UniquePtr<DebugFunc>> funcs;
+		List<UniquePtr<DebugType>> types;
+
+		DebugType* makeType(DebugType::Kind kind, String name, U32 size);
 	};
 } // namespace rat
 

src/backend/pass/emit/x86/x86_encode.cpp

@@ -564,6 +564,15 @@ namespace rat {
 			encodedFunc->lines.push_back({a->here(), src});
 	}
 
+	void X86EncodePass::recordVars(const Function& f) {
+		if(!f.getDebug())
+			return;
+		for(const DebugVarInst& v : f.getDebug()->vars) {
+			I32 off = v.slot ? fl->allocOff[v.slot->getId()] : kNoSlot;
+			encodedFunc->varFrameOff.push_back(off == kNoSlot ? kNoFrameSlot : off - detail::kCfaFromRbp);
+		}
+	}
+
 	U32 X86EncodePass::blockIdBound(const MachineFunc& f) {
 		I32 maxId = -1;
 		for(const MachineBlock& blk : f.blocks)
@@ -702,6 +711,7 @@ namespace rat {
 		if(encodedFunc) {
 			encodedFunc->textOff = off;
 			encodedFunc->size = (U32)code.size();
+			recordVars(f);
 		}
 		placed.push_back({&f, off, (U32)relocs.size()});
 		return false;

src/backend/pass/emit/x86/x86_encode.h

@@ -102,6 +102,7 @@ namespace rat {
 		void prologue();
 		void markCfi(CfiOp::Kind kind, PhysReg reg, I32 value);
 		void markLine(U32 loc);
+		void recordVars(const Function& f);
 	private:
 		std::ostream* os;
 		UniquePtr<ObjectFile> obj;

src/backend/pass/emit/x86/x86_lower.cpp

@@ -551,7 +551,9 @@ namespace rat {
 		curLoc = 0;
 		allocOff.assign(f.idBound(), kNoSlot);
 		lowerBlocks();
-		mf.aux = std::make_unique<X86FrameLayout>(frame); // the layout rides along on mf.aux
+		if(f.getDebug())
+			frame.allocOff = std::move(allocOff); // slot offsets for variable locations
+		mf.aux = std::make_unique<X86FrameLayout>(std::move(frame)); // the layout rides along on mf.aux
 	}
 
 	namespace detail {

src/backend/pass/emit/x86/x86_lower.h

@@ -300,7 +300,6 @@ namespace rat {
 		void emitPhiCopies(I32 targetBlock, I32 predIdx);
 		void emitTerminator(I32 b);
 	private:
-		static constexpr I32 kNoSlot = INT32_MIN;
 		// target
 		const X86CallConv* conv = &abi::kSysV;
 		const RegisterInfo* regs = nullptr;

src/backend/pass/emit/x86/x86_op.h

@@ -205,6 +205,8 @@ namespace rat {
 	inline Slot slot(I32 s, U32 w = 8) { return {s, w}; }
 	inline Xmm xmm(U32 n, U32 w = 8) { return {n, w}; }
 
+	constexpr I32 kNoSlot = INT32_MIN;
+
 	struct X86FrameLayout : MachineFuncAux {
 		I32 ldScratch = 0;
 		I32 vecScratch = 0;
@@ -214,6 +216,7 @@ namespace rat {
 		U32 namedGp = 0;
 		U32 namedFp = 0;
 		I32 sretSlot = 0;
+		List<I32> allocOff;
 	};
 } // namespace rat