Added optimizations to ClassifyFloat/Double functions in Mathutil.cpp…

… and to PPCCache.cpp
dolphin-emu · Jun 2, 2013 · 7aae9cc · 7aae9cc
1 parent 80b09c0
commit 7aae9cc
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Showing 2 changed files with 64 additions and 73 deletions.
diff --git a/Source/Core/Common/Src/MathUtil.cpp b/Source/Core/Common/Src/MathUtil.cpp
@@ -13,61 +13,54 @@ namespace MathUtil
 {
 
 u32 ClassifyDouble(double dvalue)
-{
-	// TODO: Optimize the below to be as fast as possible.
-	IntDouble value;
-	value.d = dvalue;
-	u64 sign = value.i & DOUBLE_SIGN;
-	u64 exp  = value.i & DOUBLE_EXP;
-	if (exp > DOUBLE_ZERO && exp < DOUBLE_EXP) 
-	{
-		// Nice normalized number.
-		return sign ? PPC_FPCLASS_NN : PPC_FPCLASS_PN;
-	}
-	else
-	{
-		u64 mantissa = value.i & DOUBLE_FRAC;
-		if (mantissa)
-		{
-			if (exp)
-			{
-				return PPC_FPCLASS_QNAN;
-			}
-			else
-			{
-				// Denormalized number.
-				return sign ? PPC_FPCLASS_ND : PPC_FPCLASS_PD;
-			}
-		}
-		else if (exp)
-		{
-			//Infinite
-			return sign ? PPC_FPCLASS_NINF : PPC_FPCLASS_PINF;
-		}
-		else
-		{
-			//Zero
-			return sign ? PPC_FPCLASS_NZ : PPC_FPCLASS_PZ;
-		}
-	}
-}
+    {
+        // TODO: Optimize the below to be as fast as possible.
+        u64 exp  = *(u64*)(&dvalue) & DOUBLE_EXP;
+        if (exp != DOUBLE_ZERO && exp != DOUBLE_EXP)
+        {
+            // Nice normalized number.
+            return *(u64*)(&dvalue)&DOUBLE_SIGN ? PPC_FPCLASS_NN : PPC_FPCLASS_PN;
+        }
+        else
+        {
+            if (*(u64*)(&dvalue) & DOUBLE_FRAC)
+            {
+                if (exp)
+                {
+                    return PPC_FPCLASS_QNAN;
+                }
+                else
+                {
+                    // Denormalized number.
+                    return *(u64*)(&dvalue)&DOUBLE_SIGN ? PPC_FPCLASS_ND : PPC_FPCLASS_PD;
+                }
+            }
+            else if (exp)
+            {
+                //Infinite
+                return *(u64*)(&dvalue)&DOUBLE_SIGN ? PPC_FPCLASS_NINF : PPC_FPCLASS_PINF;
+            }
+            else
+            {
+                //Zero
+                return *(u64*)(&dvalue)&DOUBLE_SIGN ? PPC_FPCLASS_NZ : PPC_FPCLASS_PZ;
+            }
+        }
+    }
+
 
 u32 ClassifyFloat(float fvalue)
 {
 	// TODO: Optimize the below to be as fast as possible.
-	IntFloat value;
-	value.f = fvalue;
-	u32 sign = value.i & FLOAT_SIGN;
-	u32 exp  = value.i & FLOAT_EXP;
+	u32 exp  = *(u32*)(&fvalue) & FLOAT_EXP;
 	if (exp > FLOAT_ZERO && exp < FLOAT_EXP) 
 	{
 		// Nice normalized number.
-		return sign ? PPC_FPCLASS_NN : PPC_FPCLASS_PN;
+		return *(u32*)(&fvalue) & FLOAT_SIGN ? PPC_FPCLASS_NN : PPC_FPCLASS_PN;
 	}
 	else
 	{
-		u32 mantissa = value.i & FLOAT_FRAC;
-		if (mantissa)
+		if (*(u32*)(&fvalue) & FLOAT_FRAC)
 		{
 			if (exp)
 			{
@@ -76,18 +69,18 @@ u32 ClassifyFloat(float fvalue)
 			else
 			{
 				// Denormalized number.
-				return sign ? PPC_FPCLASS_ND : PPC_FPCLASS_PD;
+				return *(u32*)(&fvalue) & FLOAT_SIGN ? PPC_FPCLASS_ND : PPC_FPCLASS_PD;
 			}
 		} 
 		else if (exp) 
 		{
 			// Infinite
-			return sign ? PPC_FPCLASS_NINF : PPC_FPCLASS_PINF;
+			return *(u32*)(&fvalue) & FLOAT_SIGN ? PPC_FPCLASS_NINF : PPC_FPCLASS_PINF;
 		} 
 		else 
 		{
 			//Zero
-			return sign ? PPC_FPCLASS_NZ : PPC_FPCLASS_PZ;
+			return *(u32*)(&fvalue) & FLOAT_SIGN ? PPC_FPCLASS_NZ : PPC_FPCLASS_PZ;
 		}
 	}
 }

diff --git a/Source/Core/Core/Src/PowerPC/PPCCache.cpp b/Source/Core/Core/Src/PowerPC/PPCCache.cpp
@@ -26,31 +26,29 @@ namespace PowerPC
 
 		for (u32 m = 0; m < 128; m++)
 		{
-			u32 b[7];
-			for (int i = 0; i < 7; i++) b[i] = m & (1<<i);
-			u32 w;
-			if (b[0])
-				if (b[2])
-					if (b[6])
-						w = 7;
-					else
-						w = 6;
-				else
-					if (b[5])
-						w = 5;
-					else
-						w = 4;
-			else
-				if (b[1])
-					if (b[4])
-						w = 3;
-					else
-						w = 2;
-				else
-					if (b[3])
-						w = 1;
-					else
-						w = 0;
+            u32 w;
+            if(m & (1<<0))
+                if(m & (1<<2))
+                    if(m & (1<<6))
+                        w=7;
+                    else
+                        w=6;
+                    else
+                        if(m & (1<<5))
+                            w=5;
+                        else
+                            w=4;
+                        else
+                            if(m & (1<<1))
+                                if(m & (1<<4))
+                                    w=3;
+                                else
+                                    w=2;
+                                else
+                                    if(m & (1<<3))
+                                        w=1;
+                                    else
+                                        w=0;
 			way_from_plru[m] = w;
 		}
 	}