Merge commit '57999ac9b9d32775efc271e0edfed27b784ee1c6' as 'parallel-rsp'

parallel-rsp/rsp_vu_fuzzer.cpp

@@ -0,0 +1,75 @@
+#include "rsp_op.hpp"
+#include "rsp_disasm.hpp"
+#include <random>
+
+using namespace RSP;
+
+static uint64_t hash_registers(const CPUState *rsp)
+{
+	uint64_t h = 0xcbf29ce484222325ull;
+	auto *data = reinterpret_cast<const uint32_t *>(&rsp->cp2);
+	unsigned words = sizeof(rsp->cp2) >> 2;
+	for (size_t i = 0; i < words; i++)
+		h = (h * 0x100000001b3ull) ^ data[i];
+
+	return h;
+}
+
+static void fill_cp2_register_state(std::mt19937 &rnd, CPUState *rsp)
+{
+	auto *data = reinterpret_cast<uint32_t *>(&rsp->cp2);
+	unsigned words = sizeof(rsp->cp2) >> 2;
+	for (unsigned i = 0; i < words; i++)
+		data[i] = rnd();
+}
+
+static void run_vu_opcode(std::mt19937 &rnd, CPUState *rsp, unsigned instr)
+{
+	fill_cp2_register_state(rnd, rsp);
+
+	uint32_t op = instr & 63;
+	uint32_t vd = (instr >> 6) & 31;
+	uint32_t vs = (instr >> 11) & 31;
+	uint32_t vt = (instr >> 16) & 31;
+	uint32_t e = (instr >> 21) & 15;
+
+	using VUOp = void (*)(RSP::CPUState *, unsigned vd, unsigned vs, unsigned vt, unsigned e);
+	static const VUOp ops[64] = {
+		RSP_VMULF, RSP_VMULU, nullptr, nullptr, RSP_VMUDL, RSP_VMUDM, RSP_VMUDN, RSP_VMUDH, RSP_VMACF, RSP_VMACU, nullptr,
+		nullptr, RSP_VMADL, RSP_VMADM, RSP_VMADN, RSP_VMADH, RSP_VADD, RSP_VSUB, nullptr, RSP_VABS, RSP_VADDC, RSP_VSUBC,
+		nullptr, nullptr, nullptr, nullptr, nullptr, nullptr, nullptr, RSP_VSAR, nullptr, nullptr, RSP_VLT,
+		RSP_VEQ, RSP_VNE, RSP_VGE, RSP_VCL, RSP_VCH, RSP_VCR, RSP_VMRG, RSP_VAND, RSP_VNAND, RSP_VOR, RSP_VNOR,
+		RSP_VXOR, RSP_VNXOR, nullptr, nullptr, RSP_VRCP, RSP_VRCPL, RSP_VRCPH, RSP_VMOV, RSP_VRSQ, RSP_VRSQL, RSP_VRSQH,
+		RSP_VNOP,
+	};
+
+	auto *vuop = ops[op];
+	if (!vuop)
+		vuop = RSP_RESERVED;
+
+	vuop(rsp, vd, vs, vt, e);
+
+	uint64_t register_hash = hash_registers(rsp);
+	auto disasm = disassemble(0, instr | (0x25u << 25u));
+	printf("%s (%llx)\n", disasm.c_str(), static_cast<unsigned long long>(register_hash));
+}
+
+int main()
+{
+	// Exhaustive test every single VU opcode with random input.
+	std::mt19937 rnd(0xf00b4); // Fixed seed.
+	CPUState state = {};
+
+	// Sweep through every opcode at least once.
+	constexpr unsigned num_opcodes = 1u << 25u;
+	for (unsigned instr = 0; instr < num_opcodes; instr++)
+		run_vu_opcode(rnd, &state, instr);
+
+	// Try random opcodes some more, should hopefully hit some interesting corner cases eventually.
+	constexpr unsigned num_random_opcodes = 50000000;
+	for (unsigned i = 0; i < num_random_opcodes; i++)
+	{
+		unsigned instr = rnd() & (num_opcodes - 1);
+		run_vu_opcode(rnd, &state, instr);
+	}
+}