Replaced all macros with static inline functions and static consts for typechecking and easier debugging.

Made 32-bit division slightly more accurate and added a TODO comment to make it as accurate as the 64-bit division.

3 files changed, 42 insertions, 86 deletions

diff --git a/libfixmath/fix16.c b/libfixmath/fix16.c
index a40f3c8..49473ca 100644
--- a/libfixmath/fix16.c
+++ b/libfixmath/fix16.c
@@ -1,27 +1,13 @@
 #include "fix16.h"

 

 

-/* Replaced as macros, these are left here to uncomment for code dependant on the symbols.

-const fix16_t fix16_pi  = 205887;

-const fix16_t fix16_e   = 178145;

-const fix16_t fix16_one = 0x00010000;

-

-double  fix16_to_dbl(const fix16_t inVal)   { return ((double)inVal / 65536.0); }

-fix16_t fix16_from_dbl(const double inVal)  { return (fix16_t)(inVal * 65536.0); }

-float   fix16_to_float(const fix16_t inVal) { return ((float)inVal / 65536.0f); }

-fix16_t fix16_from_float(const float inVal) { return (fix16_t)(inVal * 65536.0f); }

-int32_t fix16_to_int(const fix16_t inVal)   { return ((inVal + 0x00008000) >> 16); }

-fix16_t fix16_from_int(const int32_t inVal) { return (inVal << 16); }

-*/

-

-

 

 fix16_t fix16_sadd(fix16_t inArg0, fix16_t inArg1) {

 	fix16_t tempResult = (inArg0 + inArg1);

 	if((tempResult > 0) && (inArg0 < 0) && (inArg1 < 0))

-		return 0x80000000;

+		return fix16_min;

 	if((tempResult < 0) && (inArg0 > 0) && (inArg1 > 0))

-		return 0x7FFFFFFF;

+		return fix16_max;

 	return tempResult;

 }

 

@@ -60,16 +46,16 @@ fix16_t fix16_smul(fix16_t inArg0, fix16_t inArg1) {
 	tempResult += (fix16_one >> 1);

 	#endif

 	tempResult >>= 16;

-	if(tempResult < fix16_MIN)

-		return fix16_MIN;

-	if(tempResult > fix16_MAX)

-		return fix16_MAX;

+	if(tempResult < fix16_min)

+		return fix16_min;

+	if(tempResult > fix16_max)

+		return fix16_max;

 	return tempResult;

 	#else

 	 int16_t hi[2] = { (inArg0 >> 16),    (inArg1 >> 16)    };

 	 int32_t r_hi = hi[0] * hi[1];

 	 if(r_hi >> 16)

-		return (r_hi < 0 ? fix16_MIN : fix16_MAX);

+		return (r_hi < 0 ? fix16_min : fix16_max);

 

 	uint16_t lo[2] = { (inArg0 & 0xFFFF), (inArg1 & 0xFFFF) };

 	 int32_t r_md = (hi[0] * lo[1]) + (hi[1] * lo[0]);

@@ -97,8 +83,12 @@ fix16_t fix16_div(fix16_t inArg0, fix16_t inArg1) {
 	tempResult /= inArg1;

 	return tempResult;

 	#else

-	 int32_t rcp = (0xFFFFFFFF / inArg1);

-	 int32_t rcp_hi = rcp >> 16;

+	int32_t rcp = (0xFFFFFFFF / inArg1);

+	#ifndef FIXMATH_FAST_DIV

+	if(((0xFFFFFFFF % inArg1) + 1) >= inArg1)

+		rcp++;

+	#endif

+	int32_t rcp_hi = rcp >> 16;

 

 	uint32_t rcp_lo = rcp & 0xFFFF;

 	 int32_t arg_hi = (inArg0 >> 16);

@@ -113,28 +103,14 @@ fix16_t fix16_div(fix16_t inArg0, fix16_t inArg1) {
 	res += ((res_lo >> 15) & 1);

 	#endif

 	return res;

-

-	/*int32_t res = (inArg0 / inArg1) << 16;

-	int32_t mod = inArg0 % inArg1;

-	uintptr_t i;

-	for(i = 0; i < 16; i++) {

-		mod <<= 1;

-		res += (mod / inArg1) << (15 - i);

-		mod %= inArg1;

-	}

-	#ifndef FIXMATH_NO_ROUNDING

-	if((mod << 1) / inArg1)

-		res++;

-	#endif

-	return res;*/

 	#endif

 }

 

 fix16_t fix16_sdiv(fix16_t inArg0, fix16_t inArg1) {

 	if(inArg1 == 0) {

 		if(inArg0 < 0)

-			return fix16_MIN;

-		return fix16_MAX;

+			return fix16_min;

+		return fix16_max;

 	}

 	#ifndef FIXMATH_NO_64BIT

 	int64_t tempResult = inArg0;

@@ -143,18 +119,22 @@ fix16_t fix16_sdiv(fix16_t inArg0, fix16_t inArg1) {
 	tempResult += (inArg1 >> 1);

 	#endif

 	tempResult /= inArg1;

-	if(tempResult < fix16_MIN)

+	if(tempResult < fix16_min)

 		return fix16_MIN;

-	if(tempResult > fix16_MAX)

-		return fix16_MAX;

+	if(tempResult > fix16_max)

+		return fix16_max;

 	return tempResult;

 	#else

-	 int32_t rcp = (0xFFFFFFFF / inArg1);

-	 int32_t rcp_hi = rcp >> 16;

+	int32_t rcp = (0xFFFFFFFF / inArg1);

+	#ifndef FIXMATH_FAST_DIV

+	if(((0xFFFFFFFF % inArg1) + 1) >= inArg1)

+		rcp++;

+	#endif

+	int32_t rcp_hi = rcp >> 16;

 	if(rcp_hi >= 32768)

-		return fix16_MAX;

+		return fix16_max;

 	if(rcp_hi < -32768)

-		return fix16_MIN;

+		return fix16_min;

 

 	uint32_t rcp_lo = rcp & 0xFFFF;

 	 int32_t arg_hi = (inArg0 >> 16);

@@ -164,28 +144,13 @@ fix16_t fix16_sdiv(fix16_t inArg0, fix16_t inArg1) {
 	 int32_t res_md = (rcp_hi * arg_lo) + (rcp_lo * arg_hi);

 	uint32_t res_lo = rcp_lo * arg_lo;

 

+	// TODO - Check properly for overflows at this stage.

+

 	int32_t res = (res_hi << 16) + res_md + (res_lo >> 16);

 	#ifndef FIXMATH_NO_ROUNDING

 	res += ((res_lo >> 15) & 1);

 	#endif

 	return res;

-

-	/*int32_t res = (inArg0 / inArg1);

-	if((res < -32768) || (res >= 32768))

-		return (res < 0 ? fix16_MIN : fix16_MAX);

-	res <<= 16;

-	int32_t mod = inArg0 % inArg1;

-	uintptr_t i;

-	for(i = 0; i < 16; i++) {

-		mod <<= 1;

-		res += (mod / inArg1) << (15 - i);

-		mod %= inArg1;

-	}

-	#ifndef FIXMATH_NO_ROUNDING

-	if((mod << 1) / inArg1)

-		res++;

-	#endif

-	return res;*/

 	#endif

 }

 

diff --git a/libfixmath/fix16.h b/libfixmath/fix16.h
index b947976..d1a1230 100644
--- a/libfixmath/fix16.h
+++ b/libfixmath/fix16.h
@@ -10,42 +10,33 @@ extern "C"
 

 typedef int32_t fix16_t;

 

-#define fix16_MAX (fix16_t)0x7FFFFFFF /*!< the maximum value of fix16_t */

-#define fix16_MIN (fix16_t)0x80000000 /*!< the minimum value of fix16_t */

+static const fix16_t fix16_max = 0x7FFFFFFF; /*!< the maximum value of fix16_t */

+static const fix16_t fix16_min = 0x80000000; /*!< the minimum value of fix16_t */

 

-#define fix16_pi  205887     /*!< fix16_t value of pi */

-#define fix16_e   178145     /*!< fix16_t value of e */

-#define fix16_one 0x00010000 /*!< fix16_t value of 1 */

+static const fix16_t fix16_pi  = 205887;     /*!< fix16_t value of pi */

+static const fix16_t fix16_e   = 178145;     /*!< fix16_t value of e */

+static const fix16_t fix16_one = 0x00010000; /*!< fix16_t value of 1 */

 

 #ifdef FIXMATH_NO_ROUNDING

 /*! Converts a double to a fix16_t and returns the result. */

-#define fix16_from_dbl(inVal) ((fix16_t)((inVal) * 65536.0))

+static inline fix16_t fix16_from_dbl(const double inVal)  { return (fix16_t)(inVal * 65536.0); }

 /*! Converts a float to a fix16_t and returns the result. */

-#define fix16_from_float(inVal) ((fix16_t)((inVal) * 65536.0f))

+static inline fix16_t fix16_from_float(const float inVal) { return (fix16_t)(inVal * 65536.0f); }

 #else

 /*! Converts a double to a fix16_t and returns the result. */

-#define fix16_from_dbl(inVal) ((fix16_t)(((inVal) * 65536.0) + 0.5))

+static inline fix16_t fix16_from_dbl(const double inVal)  { return (fix16_t)((inVal * 65536.0) + 0.5); }

 /*! Converts a float to a fix16_t and returns the result. */

-#define fix16_from_float(inVal) ((fix16_t)(((inVal) * 65536.0f) + 0.5f))

+static inline fix16_t fix16_from_float(const float inVal) { return (fix16_t)((inVal * 65536.0f) + 0.5f); }

 #endif

 /*! Converts a signed integer to a fix16_t and returns the result. */

-#define fix16_from_int(inVal) ((fix16_t)((inVal) << 16))

+static inline fix16_t fix16_from_int(const int32_t inVal) { return (inVal << 16); }

 

 /*! Coverts a fix16_t to a double and returns the result. */

-#define fix16_to_dbl(inVal) ((double)((inVal) / 65536.0))

+static inline double  fix16_to_dbl(const fix16_t inVal)   { return ((double)inVal / 65536.0); }

 /*! Converts a fix16_t to a float and returns the result. */

-#define fix16_to_float(inVal) ((float)((inVal) / 65536.0f))

+static inline float   fix16_to_float(const fix16_t inVal) { return ((float)inVal / 65536.0f); }

 /*! Converts a fix16_t to a signed integer and returns the result. */

-#define fix16_to_int(inVal) ((int32_t)(((inVal) + (fix16_one >> 1)) >> 16))

-

-/* Replaced with macros, uncomment if symbols are needed by old code.

-extern double  fix16_to_dbl(const fix16_t inVal);

-extern fix16_t fix16_from_dbl(const double inVal);

-extern float   fix16_to_float(const fix16_t inVal);

-extern fix16_t fix16_from_float(const float inVal);

-extern int32_t fix16_to_int(const fix16_t inVal);

-extern fix16_t fix16_from_int(const int32_t inVal);

-*/

+static inline int32_t fix16_to_int(const fix16_t inVal)   { return ((inVal + 0x00008000) >> 16); }

 

 

 

diff --git a/libfixmath/fix16_exp.c b/libfixmath/fix16_exp.c
index 014fa1c..d48698a 100644
--- a/libfixmath/fix16_exp.c
+++ b/libfixmath/fix16_exp.c
@@ -15,7 +15,7 @@ fix16_t fix16_exp(fix16_t inValue) {
 	if(inValue == fix16_one)

 		return fix16_e;

 	if(inValue > 681391)

-		return fix16_MAX;

+		return fix16_max;

 	if(inValue < -726817)

 		return 0;