Add basic kernel math support

xtoskrnl/rtl/math.c

@@ -0,0 +1,327 @@
+/**
+ * PROJECT:         ExectOS
+ * COPYRIGHT:       See COPYING.md in the top level directory
+ * FILE:            xtoskrnl/rtl/math.c
+ * DESCRIPTION:     Kernel math support
+ * DEVELOPERS:      Rafal Kupiec <belliash@codingworkshop.eu.org>
+ */
+
+#include <xtos.h>
+
+
+/**
+ * Converts the 32-bit signed value to a large integer.
+ *
+ * @param Value
+ *        Supplies the value to convert.
+ *
+ * @return This routine returns the large integer representation of the given value.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+LARGE_INTEGER
+RtlConvertToLargeInteger32(IN LONG Value)
+{
+    LARGE_INTEGER LargeInt;
+
+    /* Convert the value to a large integer and return it */
+    LargeInt.QuadPart = Value;
+    return LargeInt;
+}
+
+/**
+ * Converts the 32-bit unsigned value to a large integer.
+ *
+ * @param Value
+ *        Supplies the value to convert.
+ *
+ * @return This routine returns the large integer representation of the given value.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+LARGE_INTEGER
+RtlConvertToLargeIntegerUnsigned32(IN ULONG Value)
+{
+    LARGE_INTEGER LargeInt;
+
+    /* Convert the value to a large integer and return it */
+    LargeInt.QuadPart = Value;
+    return LargeInt;
+}
+
+/**
+ * Determines the number of leading zero bits in a 32-bit unsigned value.
+ *
+ * @param Value
+ *        Supplies the value whose leading zero bits are to be counted.
+ *
+ * @return This routine returns the number of leading zero bits in the given value.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+INT
+RtlCountLeadingZeroes32(IN ULONG Value)
+{
+    /* Return a number of leading zero bits */
+    return __builtin_clzl(Value);
+}
+
+/**
+ * Determines the number of leading zero bits in a 64-bit unsigned value.
+ *
+ * @param Value
+ *        Supplies the value whose leading zero bits are to be counted.
+ *
+ * @return This routine returns the number of leading zero bits in the given value.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+INT
+RtlCountLeadingZeroes64(IN ULONG Value)
+{
+    /* Return a number of leading zero bits */
+    return __builtin_clzll(Value);
+}
+
+/**
+ * Determines the number of trailing zero bits in a 32-bit unsigned value.
+ *
+ * @param Value
+ *        Supplies the value whose trailing zero bits are to be counted.
+ *
+ * @return This routine returns the number of trailing zero bits in the given value.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+INT
+RtlCountTrailingZeroes32(IN ULONG Value)
+{
+    /* Return a number of trailing zero bits */
+    return __builtin_ctzl(Value);
+}
+
+/**
+ * Determines the number of trailing zero bits in a 64-bit unsigned value.
+ *
+ * @param Value
+ *        Supplies the value whose trailing zero bits are to be counted.
+ *
+ * @return This routine returns the number of trailing zero bits in the given value.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+INT
+RtlCountTrailingZeroes64(IN ULONGLONG Value)
+{
+    /* Return a number of trailing zero bits */
+    return __builtin_ctzll(Value);
+}
+
+/**
+ * Performs a 32-bit divide operation on signed integer numbers.
+ *
+ * @param Dividend
+ *        Supplies a number that is going to be divided.
+ *
+ * @param Divisor
+ *        Supplies a number by which the dividend is divided.
+ *
+ * @param Remainder
+ *        Supplies a pointer that receives the divide remainder.
+ *
+ * @return This routine returns the quotient.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+LONGLONG
+RtlDivide32(IN LONG Dividend,
+            IN LONG Divisor,
+            OUT PLONG Remainder)
+{
+    LONG Quotient;
+
+    /* Calculate the quotient */
+    Quotient = Dividend / Divisor;
+
+    /* Make sure a pointer to remainder provided */
+    if(Remainder)
+    {
+        /* Calculate remainder */
+        *Remainder = Dividend - (Quotient * Divisor);
+    }
+
+    /* Return the quotient */
+    return Quotient;
+}
+
+/**
+ * Performs a 64-bit divide operation on signed integer numbers.
+ *
+ * @param Dividend
+ *        Supplies a number that is going to be divided.
+ *
+ * @param Divisor
+ *        Supplies a number by which the dividend is divided.
+ *
+ * @param Remainder
+ *        Supplies a pointer that receives the divide remainder.
+ *
+ * @return This routine returns the quotient.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+LONGLONG
+RtlDivide64(IN LONGLONG Dividend,
+            IN LONGLONG Divisor,
+            OUT PLONGLONG Remainder)
+{
+    LONGLONG Quotient;
+
+    /* Calculate the quotient */
+    Quotient = Dividend / Divisor;
+
+    /* Make sure a pointer to remainder provided */
+    if(Remainder)
+    {
+        /* Calculate remainder */
+        *Remainder = Dividend - (Quotient * Divisor);
+    }
+
+    /* Return the quotient */
+    return Quotient;
+}
+
+/**
+ * Performs a 32-bit divide operation on unsigned integer numbers.
+ *
+ * @param Dividend
+ *        Supplies an unsigned number that is going to be divided.
+ *
+ * @param Divisor
+ *        Supplies an unsigned number by which the dividend is divided.
+ *
+ * @param Remainder
+ *        Supplies a pointer that receives the unsigned divide remainder.
+ *
+ * @return This routine returns the quotient.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+ULONGLONG
+RtlDivideUnsigned32(IN ULONG Dividend,
+                    IN ULONG Divisor,
+                    OUT PULONG Remainder)
+{
+    /* Make sure a pointer to remainder provided */
+    if(Remainder)
+    {
+        /* Calculate remainder */
+        *Remainder = Dividend % Divisor;
+    }
+
+    /* Return the quotient */
+    return Dividend / Divisor;
+}
+
+/**
+ * Performs a 64-bit divide operation on unsigned integer numbers.
+ *
+ * @param Dividend
+ *        Supplies an unsigned number that is going to be divided.
+ *
+ * @param Divisor
+ *        Supplies an unsigned number by which the dividend is divided.
+ *
+ * @param Remainder
+ *        Supplies a pointer that receives the unsigned divide remainder.
+ *
+ * @return This routine returns the quotient.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+ULONGLONG
+RtlDivideUnsigned64(IN ULONGLONG Dividend,
+                    IN ULONGLONG Divisor,
+                    OUT PULONGLONG Remainder)
+{
+    /* Make sure a pointer to remainder provided */
+    if(Remainder)
+    {
+        /* Calculate remainder */
+        *Remainder = Dividend % Divisor;
+    }
+
+    /* Return the quotient */
+    return Dividend / Divisor;
+}
+
+/**
+ * Divides a signed large integer by a 32-bit divisor.
+ *
+ * @param Dividend
+ *        Supplies a large integer to be divided.
+ *
+ * @param Divisor
+ *        Supplies a 32-bit divisor.
+ *
+ * @param Remainder
+ *        Supplies a pointer that receives the divide remainder.
+ *
+ * @return This routine returns the quotient.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+LARGE_INTEGER
+RtlDivideLargeInteger(IN LARGE_INTEGER Dividend,
+                      IN ULONG Divisor,
+                      OUT PULONG Remainder)
+{
+    LARGE_INTEGER LargeInt;
+
+    /* Make sure a pointer to remainder provided */
+    if(Remainder)
+    {
+        /* Calculate remainder */
+        *Remainder = Dividend.QuadPart % Divisor;
+    }
+
+    /* Return the quotient */
+    LargeInt.QuadPart = Dividend.QuadPart / Divisor;
+    return LargeInt;
+}
+
+/**
+ * Multiplies a signed large integer by a signed integer.
+ *
+ * @param Multiplicand
+ *        Supplies a large integer to be multiplied.
+ *
+ * @param Multiplier
+ *        Supplies an integer by which the large integer is multiplied.
+ *
+ * @return This routine returns the result of the multiplication.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+LARGE_INTEGER
+RtlMultiplyLargeInteger(IN LARGE_INTEGER Multiplicand,
+                        IN LONG Multiplier)
+{
+    LARGE_INTEGER LargeInt;
+
+    /* Perform multiplication and return the result */
+    LargeInt.QuadPart = (LONGLONG) Multiplicand.QuadPart * Multiplier;
+    return LargeInt;
+}