port from perforce

4kgfx/small.h

@@ -0,0 +1,128 @@
+#pragma once
+
+#pragma code_seg("pi")
+__forceinline float pi()
+{
+	__asm fldpi
+}
+
+#pragma code_seg("sm0")
+
+unsigned long ftol(float Value)
+{
+	unsigned long RetVal;
+	__asm fld Value
+	__asm fistp RetVal
+	return RetVal;
+}
+
+#pragma code_seg("sm1")
+
+float frac(float Value)
+{
+	return Value - ftol(Value);
+}
+
+#pragma code_seg("sm2")
+
+float abs(float Value)
+{
+	__asm fld	Value
+	__asm fabs
+}
+
+#pragma code_seg("sm3")
+
+float sin(float Value)
+{
+	__asm fld	Value
+	__asm fsin
+}
+
+#pragma code_seg("sm4")
+
+float sign(float Value)
+{
+	if (Value != 0)
+		return Value / abs(Value);
+
+	return 1.0f;
+}
+
+#pragma code_seg("sm5")
+
+float sqrt(float Value)
+{
+	__asm fld Value
+	__asm fsqrt
+}
+
+#pragma code_seg("sm7")
+
+void* memcpy(void* Dest, const void* Src, size_t destSize)
+{
+	__asm mov esi, Src
+	__asm mov edi, Dest
+	__asm mov ecx, destSize
+	__asm rep movsb
+}
+
+#pragma code_seg("sm8")
+
+float fmod(float x, float y)
+{
+	__asm fld	y
+	__asm fld	x
+	__asm fprem
+	__asm fxch
+	__asm fstp	x
+}
+
+#pragma data_seg("smA")
+
+static unsigned long seed=0x12345678;
+
+#pragma code_seg("sm9")
+
+__forceinline void randomize(unsigned long x)
+{
+	seed = x;
+}
+
+#pragma code_seg("smB")
+
+float rand()
+{
+	seed = seed * 0x76364873 + 1234567;
+	return (float)(seed & 0x7FFFFFFF) * (const float)(2.0f / (float)0x7FFFFFFF) - 1.0f;
+}
+
+#pragma code_seg("smS")
+
+__forceinline size_t strlen(const char* String)
+{
+	size_t Length = 0;
+	while (*String++) ++Length;
+	return Length;
+}
+
+#pragma code_seg("smP")
+
+float pow(float x, float y){
+	float r;
+	__asm{
+		fld y
+		fld x
+		fyl2x
+		fld1
+		fld st(1)
+		fprem
+		f2xm1
+		faddp st(1),st
+		fscale
+		fxch st(1)
+		fstp st(0)
+		fstp r
+	}
+	return r;
+}