Shortcut zero page register moves

include/c64/vic.c

@@ -40,6 +40,8 @@ void vic_setmode(VicMode mode, char * text, char * font)
 			vic.ctrl1 = VIC_CTRL1_BMM | VIC_CTRL1_DEN | VIC_CTRL1_RSEL | 3;
 			vic.ctrl2 = VIC_CTRL2_CSEL | VIC_CTRL2_MCM;
 			break;
+		default:
+			__assume(false)
 	}
 
 	cia2.pra = (cia2.pra & 0xfc) | (((unsigned)text >> 14) ^ 0x03);	

oscar64/NativeCodeGenerator.cpp

@@ -10704,6 +10704,73 @@ bool NativeCodeBasicBlock::MoveAbsoluteLoadStoreUp(int at)
 	return false;
 }
 
+bool NativeCodeBasicBlock::ReplaceZeroPageUp(int at)
+{
+	int i = at - 1;
+	while (i >= 0)
+	{
+		if ((mIns[i].mType == ASMIT_STA || mIns[i].mType == ASMIT_STX || mIns[i].mType == ASMIT_STY) && mIns[i].mMode == ASMIM_ZERO_PAGE && mIns[i].mAddress == mIns[at].mAddress)
+		{
+			while (i < at)
+			{
+				if (mIns[i].mMode == ASMIM_ZERO_PAGE && mIns[i].mAddress == mIns[at].mAddress)
+					mIns[i].mAddress = mIns[at + 1].mAddress;
+				i++;
+			}
+
+			mIns[at + 0].mType = ASMIT_NOP; mIns[at + 0].mMode = ASMIM_IMPLIED;
+			mIns[at + 1].mType = ASMIT_NOP; mIns[at + 1].mMode = ASMIM_IMPLIED;
+
+			return true;
+		}
+
+		if (mIns[i].mType == ASMIT_JSR)
+			return false;
+
+		if (mIns[i].ChangesZeroPage(mIns[at + 1].mAddress))
+			return false;
+		if (mIns[i].UsesZeroPage(mIns[at + 1].mAddress))
+			return false;
+		if (mIns[i].mMode == ASMIM_INDIRECT_Y && (mIns[i].mAddress == mIns[at].mAddress || mIns[i].mAddress + 1 == mIns[at].mAddress))
+			return false;
+
+		i--;
+	}
+
+	return false;
+}
+
+
+bool NativeCodeBasicBlock::MoveLoadXUp(int at)
+{
+	int	i = at - 1;
+	while (i >= 0)
+	{
+		if (mIns[i].mType == ASMIT_STA && mIns[i].mMode == ASMIM_ZERO_PAGE && mIns[i].mAddress == mIns[at].mAddress)
+		{
+			mIns[i].mType = ASMIT_TAX;
+			mIns[i].mMode = ASMIM_IMPLIED;
+			mIns[at].mType = ASMIT_NOP;
+			mIns[at].mMode = ASMIM_IMPLIED;
+			while (i < at)
+			{
+				mIns[i].mLive |= LIVE_CPU_REG_X;
+				i++;
+			}
+
+			return true;
+		}
+
+		if (mIns[i].ChangesXReg() || (mIns[i].mLive & LIVE_CPU_REG_X) || mIns[i].UsesZeroPage(mIns[at].mAddress))
+			return false;
+
+		i--;
+	}
+
+	return false;
+}
+
+
 bool NativeCodeBasicBlock::MoveStoreXUp(int at)
 {
 	bool	done = false;
@@ -11283,6 +11350,68 @@ bool NativeCodeBasicBlock::OptimizeSimpleLoopInvariant(NativeCodeProcedure* proc
 		return true;
 	}
 
+	if (sz >= 3 && mIns[0].mType == ASMIT_LDX && mIns[sz - 2].mType == ASMIT_LDA && mIns[0].SameEffectiveAddress(mIns[sz - 2]) &&
+		mIns[sz - 1].mType == ASMIT_CMP && HasAsmInstructionMode(ASMIT_CPX, mIns[sz - 1].mMode) && !(mIns[sz - 1].mLive & LIVE_CPU_REG_A))
+	{
+		if (!prevBlock)
+			return OptimizeSimpleLoopInvariant(proc);
+
+		mIns[sz - 2].mType = ASMIT_LDX;
+		mIns[sz - 1].mType = ASMIT_CPX;
+
+		prevBlock->mIns.Push(mIns[0]);
+		mIns.Remove(0);
+		return true;
+	}
+
+	if (sz >= 2 && mIns[0].mType == ASMIT_LDY && mIns[0].mMode == ASMIM_ZERO_PAGE)
+	{
+		int	i = mIns.Size() - 1;
+		while (i > 0 && !mIns[i].ChangesYReg() && !mIns[i].ChangesZeroPage(mIns[0].mAddress))
+			i--;
+
+		if (i > 0 &&
+			(mIns[i].mType == ASMIT_LDY && mIns[i].mMode == ASMIM_ZERO_PAGE && mIns[i].mAddress == mIns[0].mAddress) ||
+			(mIns[i].mType == ASMIT_TAY && (mIns[i - 1].mType == ASMIT_LDA || mIns[i - 1].mType == ASMIT_STA) && mIns[i - 1].mMode == ASMIM_ZERO_PAGE && mIns[i - 1].mAddress == mIns[0].mAddress))
+		{
+			if (!prevBlock)
+				return OptimizeSimpleLoopInvariant(proc);
+			while (i < mIns.Size())
+			{
+				mIns[i].mLive |= LIVE_CPU_REG_Y;
+				i++;
+			}
+
+			prevBlock->mIns.Push(mIns[0]);
+			mIns.Remove(0);
+			return true;
+		}
+	}
+
+	if (sz >= 2 && mIns[0].mType == ASMIT_LDX && mIns[0].mMode == ASMIM_ZERO_PAGE)
+	{
+		int	i = mIns.Size() - 1;
+		while (i > 0 && !mIns[i].ChangesXReg() && !mIns[i].ChangesZeroPage(mIns[0].mAddress))
+			i--;
+
+		if (i > 0 &&
+			(mIns[i].mType == ASMIT_LDX && mIns[i].mMode == ASMIM_ZERO_PAGE && mIns[i].mAddress == mIns[0].mAddress) ||
+			(mIns[i].mType == ASMIT_TAX && (mIns[i - 1].mType == ASMIT_LDA || mIns[i - 1].mType == ASMIT_STA) && mIns[i - 1].mMode == ASMIM_ZERO_PAGE && mIns[i - 1].mAddress == mIns[0].mAddress))
+		{
+			if (!prevBlock)
+				return OptimizeSimpleLoopInvariant(proc);
+			while (i < mIns.Size())
+			{
+				mIns[i].mLive |= LIVE_CPU_REG_X;
+				i++;
+			}
+
+			prevBlock->mIns.Push(mIns[0]);
+			mIns.Remove(0);
+			return true;
+		}
+	}
+
 
 	int	ai = 0;
 	while (ai < mIns.Size() && !mIns[ai].ChangesAccu())
@@ -13033,6 +13162,20 @@ bool NativeCodeBasicBlock::PeepHoleOptimizer(int pass)
 		}
 #endif
 
+#if 1
+		// replace zero page up
+
+		for (int i = 1; i + 1 < mIns.Size(); i++)
+		{
+			if (mIns[i].mType == ASMIT_LDA && mIns[i].mMode == ASMIM_ZERO_PAGE && mIns[i + 1].mType == ASMIT_STA && mIns[i + 1].mMode == ASMIM_ZERO_PAGE && !(mIns[i + 1].mLive & (LIVE_CPU_REG_A | LIVE_CPU_REG_Z)) && !(mIns[i + 0].mLive & LIVE_MEM))
+			{
+				if (ReplaceZeroPageUp(i))
+					changed = true;
+			}
+		}
+#endif
+
+
 #if 1
 		// move load store pairs up to initial store
 
@@ -13214,6 +13357,11 @@ bool NativeCodeBasicBlock::PeepHoleOptimizer(int pass)
 				if (MoveStoreXUp(i))
 					changed = true;
 			}
+			else if (mIns[i].mType == ASMIT_LDX && mIns[i].mMode == ASMIM_ZERO_PAGE && !(mIns[i].mLive & LIVE_MEM))
+			{
+				if (MoveLoadXUp(i))
+					changed = true;
+			}
 		}
 #endif
 

oscar64/NativeCodeGenerator.h

@@ -227,9 +227,11 @@ public:
 	bool FindExternAddressSumY(int at, int reg, int& breg, int& ireg);
 	bool FindPageStartAddress(int at, int reg, int& addr);
 	bool MoveStoreXUp(int at);
+	bool MoveLoadXUp(int at);
 	bool MoveStoreHighByteDown(int at);
 	bool MoveAddHighByteDown(int at);
 	bool ReverseLoadCommutativeOpUp(int aload, int aop);
+	bool ReplaceZeroPageUp(int at);
 
 	bool FindImmediateStore(int at, int reg, const NativeCodeInstruction*& ains);
 

samples/games/missile.c

@@ -833,7 +833,7 @@ int main(void)
 
 	// Build to multicolor highres at top of screen
 	rirq_build(&top, 3);
-	rirq_delay(&top, 9);
+	rirq_delay(&top, 10);
 	rirq_write(&top, 1, &vic.ctrl1, VIC_CTRL1_BMM | VIC_CTRL1_DEN | VIC_CTRL1_RSEL | 3);
 	rirq_write(&top, 2, &vic.memptr, 0x28);
 	rirq_set(0, 57, &top);