samplerjit: Refactor nearest using reg cache.

GPU/Software/RasterizerRegCache.cpp

@@ -335,6 +335,28 @@ void RegCache::GrabReg(Reg r, Purpose p, bool &needsSwap, Reg swapReg, Purpose s
 	_assert_msg_(false, "softjit GrabReg() reg that isn't there");
 }
 
+bool RegCache::ChangeReg(Reg r, Purpose p) {
+	for (auto &reg : regs) {
+		if (reg.reg != r)
+			continue;
+		if ((reg.purpose & FLAG_GEN) != (p & FLAG_GEN))
+			continue;
+
+		if (reg.purpose == p)
+			return true;
+		_assert_msg_(!Has(p), "softjit ChangeReg() duplicate purpose (%04X)", p);
+
+		if (reg.locked != 0 || reg.forceRetained)
+			return false;
+
+		reg.purpose = p;
+		return true;
+	}
+
+	_assert_msg_(false, "softjit ChangeReg() reg that isn't there");
+	return false;
+}
+
 RegCache::RegStatus *RegCache::FindReg(Reg r, Purpose p) {
 	for (auto &reg : regs) {
 		if (reg.reg == r && reg.purpose == p) {

GPU/Software/RasterizerRegCache.h

@@ -92,12 +92,23 @@ struct RegCache {
 		GEN_STENCIL = 0x0103,
 		GEN_COLOR_OFF = 0x0104,
 		GEN_DEPTH_OFF = 0x0105,
+		GEN_RESULT = 0x0106,
+		GEN_SHIFTVAL = 0x0107,
 
 		GEN_ARG_X = 0x0180,
 		GEN_ARG_Y = 0x0181,
 		GEN_ARG_Z = 0x0182,
 		GEN_ARG_FOG = 0x0183,
 		GEN_ARG_ID = 0x0184,
+		GEN_ARG_U = 0x0185,
+		GEN_ARG_V = 0x0186,
+		GEN_ARG_TEXPTR = 0x0187,
+		GEN_ARG_BUFW = 0x0188,
+		GEN_ARG_LEVEL = 0x0189,
+		GEN_ARG_U_PTR = 0x018A,
+		GEN_ARG_V_PTR = 0x018B,
+		GEN_ARG_FRAC_U = 0x018C,
+		GEN_ARG_FRAC_V = 0x018D,
 		VEC_ARG_COLOR = 0x0080,
 		VEC_ARG_MASK = 0x0081,
 
@@ -170,6 +181,8 @@ struct RegCache {
 
 	// For getting a specific reg.  WARNING: May return a locked reg, so you have to check.
 	void GrabReg(Reg r, Purpose p, bool &needsSwap, Reg swapReg, Purpose swapPurpose);
+	// For setting the purpose of a specific reg.  Returns false if it is locked.
+	bool ChangeReg(Reg r, Purpose p);
 
 private:
 	RegStatus *FindReg(Reg r, Purpose p);

GPU/Software/Sampler.h

@@ -84,6 +84,7 @@ private:
 
 	std::unordered_map<SamplerID, NearestFunc> cache_;
 	std::unordered_map<SamplerID, const u8 *> addresses_;
+	Rasterizer::RegCache regCache_;
 };
 
 };