GTE: Add register names for debugging

src/core/cpu_pgxp.cpp

@@ -149,8 +149,8 @@ void CPU::PGXP::Shutdown()
   }
 
   std::memset(g_state.pgxp_gte, 0, sizeof(g_state.pgxp_gte));
-
   std::memset(g_state.pgxp_gpr, 0, sizeof(g_state.pgxp_gpr));
+
   std::memset(g_state.pgxp_cop0, 0, sizeof(g_state.pgxp_cop0));
 }
 
@@ -178,12 +178,12 @@ void CPU::PGXP::Shutdown()
 
 ALWAYS_INLINE_RELEASE void CPU::PGXP::MakeValid(PGXP_value* pV, u32 psxV)
 {
-  if (VALID_01 != (pV->flags & VALID_01))
+  if ((pV->flags & VALID_01) != VALID_01)
   {
     pV->x = static_cast<float>(static_cast<s16>(Truncate16(psxV)));
     pV->y = static_cast<float>(static_cast<s16>(Truncate16(psxV >> 16)));
     pV->z = 0.f;
-    pV->flags |= VALID_01;
+    pV->flags = VALID_01;
     pV->value = psxV;
   }
 }
@@ -276,9 +276,19 @@ ALWAYS_INLINE_RELEASE void CPU::PGXP::ValidateAndCopyMem16(PGXP_value* dest, u32
     }
 
     // truncate value
-    dest->y = (dest->x < 0) ? -1.f * sign : 0.f; // 0.f;
+    if (dest->compFlags[0] == VALID)
+    {
+      // only set y as valid if x is also valid.. don't want to make fake values
+      dest->y = (dest->x < 0) ? -1.f * sign : 0.f; // 0.f;
+      dest->compFlags[1] = VALID; // iCB: High word is valid, just 0
+    }
+    else
+    {
+      dest->y = 0.0f;
+      dest->compFlags[1] = 0;
+    }
+
     dest->value = value;
-    dest->compFlags[1] = VALID; // iCB: High word is valid, just 0
     return;
   }
 
@@ -562,9 +572,7 @@ void CPU::PGXP::CPU_SB(u32 instr, u32 addr, u32 rtVal)
 void CPU::PGXP::CPU_SH(u32 instr, u32 addr, u32 rtVal)
 {
   PGXP_value* val = &g_state.pgxp_gpr[rt(instr)];
-
-  // validate and copy half value
-  MaskValidate(val, rtVal, 0xFFFF, VALID_0);
+  Validate(val, rtVal);
   WriteMem16(val, addr);
 }
 
@@ -1391,6 +1399,16 @@ void CPU::PGXP::CPU_SRA(u32 instr, u32 rtVal)
   ret.x = (float)x;
   ret.y = (float)y;
 
+  // Use low precision/rounded values when we're not shifting an entire component,
+  // and it's not originally from a 3D value. Too many false positives in P2/etc.
+  // What we probably should do is not set the valid flag on non-3D values to begin
+  // with, only letting them become valid when used in another expression.
+  if (!(ret.flags & VALID_2) && sh < 16)
+  {
+    ret.flags = 0;
+    MakeValid(&ret, rdVal);
+  }
+
   ret.value = rdVal;
   g_state.pgxp_gpr[rd(instr)] = ret;
 }

src/core/gte.cpp

@@ -1401,3 +1401,15 @@ GTE::InstructionImpl GTE::GetInstructionImpl(u32 inst_bits, TickCount* ticks)
       Panic("Missing handler");
   }
 }
+
+const char* GTE::GetRegisterName(u32 index)
+{
+  static constexpr std::array<const char*, 64> names = {
+    {"V0_XY", "V0_Z",  "V1_XY", "V1_Z",  "V2_XY", "V2_Z",  "RGBC", "OTZ",  "IR0",  "IR1",   "IR2",   "IR3",   "SXY0",
+     "SXY1",  "SXY2",  "SXYP",  "SZ0",   "SZ1",   "SZ2",   "SZ3",  "RGB0", "RGB1", "RGB2",  "RES1",  "MAC0",  "MAC1",
+     "MAC2",  "MAC3",  "IRGB",  "ORGB",  "LZCS",  "LZCR",  "RT_0", "RT_1", "RT_2", "RT_3",  "RT_4",  "TRX",   "TRY",
+     "TRZ",   "LLM_0", "LLM_1", "LLM_2", "LLM_3", "LLM_4", "RBK",  "GBK",  "BBK",  "LCM_0", "LCM_1", "LCM_2", "LCM_3",
+     "LCM_4", "RFC",   "GFC",   "BFC",   "OFX",   "OFY",   "H",    "DQA",  "DQB",  "ZSF3",  "ZSF4",  "FLAG"}};
+
+  return (index < names.size()) ? names[index] : "";
+}

src/core/gte.h

@@ -25,4 +25,6 @@ void ExecuteInstruction(u32 inst_bits);
 using InstructionImpl = void (*)(Instruction);
 InstructionImpl GetInstructionImpl(u32 inst_bits, TickCount* ticks);
 
+const char* GetRegisterName(u32 index);
+
 } // namespace GTE