tgmath.h: better comments

diff --git a/include/tgmath.h b/include/tgmath.h
index 9034ef7..840a8d2 100644 (file)
--- a/include/tgmath.h
+++ b/include/tgmath.h
@@ -2,12 +2,12 @@
 #define _TGMATH_H
 
 /*
 #define _TGMATH_H
 
 /*

-the return types are only set correctly whit gcc (__GNUC__)
+the return types are only correctly with gcc (__GNUC__)

 otherwise they are long double or long double complex
 
 the long double version of a function is never chosen when
 sizeof(double) == sizeof(long double)
 otherwise they are long double or long double complex
 
 the long double version of a function is never chosen when
 sizeof(double) == sizeof(long double)

-(but the return type is set correctly)
+(but the return type is set correctly with gcc)

 */
 
 #include <math.h>
 */
 
 #include <math.h>


@@ -24,12 +24,14 @@ sizeof(double) == sizeof(long double)
 #define __DBLCX(x) (__IS_CX(x) && sizeof(x) == sizeof(double complex))
 #define __LDBLCX(x) (__IS_CX(x) && sizeof(x) == sizeof(long double complex) && sizeof(long double) != sizeof(double))
 
 #define __DBLCX(x) (__IS_CX(x) && sizeof(x) == sizeof(double complex))
 #define __LDBLCX(x) (__IS_CX(x) && sizeof(x) == sizeof(long double complex) && sizeof(long double) != sizeof(double))
 

+/* return type */
+

 #ifdef __GNUC__
 #ifdef __GNUC__

-/* arg type if it's floating-point else double (using ?: with null pointers) */
+/* cast to double when x is integral, otherwise use typeof(x) */

 #define __RETCAST(x) (__typeof__(*( \
        0 ? (__typeof__(0 ? (double *)0 : (void *)__IS_FP(x)))0 : \
            (__typeof__(0 ? (__typeof__(x) *)0 : (void *)!__IS_FP(x)))0 )))
 #define __RETCAST(x) (__typeof__(*( \
        0 ? (__typeof__(0 ? (double *)0 : (void *)__IS_FP(x)))0 : \
            (__typeof__(0 ? (__typeof__(x) *)0 : (void *)!__IS_FP(x)))0 )))

-/* two args case, consider complex types (for cpow) */
+/* 2 args case, consider complex types (for cpow) */

 #define __RETCAST_2(x, y) (__typeof__(*( \
        0 ? (__typeof__(0 ? (double *)0 : \
                (void *)!((!__IS_FP(x) || !__IS_FP(y)) && __FLT((x)+(y)+1.0f))))0 : \
 #define __RETCAST_2(x, y) (__typeof__(*( \
        0 ? (__typeof__(0 ? (double *)0 : \
                (void *)!((!__IS_FP(x) || !__IS_FP(y)) && __FLT((x)+(y)+1.0f))))0 : \


@@ -37,7 +39,7 @@ sizeof(double) == sizeof(long double)
                (void *)!((!__IS_FP(x) || !__IS_FP(y)) && __FLTCX((x)+(y)))))0 : \
            (__typeof__(0 ? (__typeof__((x)+(y)) *)0 : \
                (void *)((!__IS_FP(x) || !__IS_FP(y)) && (__FLT((x)+(y)+1.0f) || __FLTCX((x)+(y))))))0 )))
                (void *)!((!__IS_FP(x) || !__IS_FP(y)) && __FLTCX((x)+(y)))))0 : \
            (__typeof__(0 ? (__typeof__((x)+(y)) *)0 : \
                (void *)((!__IS_FP(x) || !__IS_FP(y)) && (__FLT((x)+(y)+1.0f) || __FLTCX((x)+(y))))))0 )))

-/* three args case, don't consider complex types (fma only) */
+/* 3 args case, don't consider complex types (fma only) */

 #define __RETCAST_3(x, y, z) (__typeof__(*( \
        0 ? (__typeof__(0 ? (double *)0 : \
                (void *)!((!__IS_FP(x) || !__IS_FP(y) || !__IS_FP(z)) && __FLT((x)+(y)+(z)+1.0f))))0 : \
 #define __RETCAST_3(x, y, z) (__typeof__(*( \
        0 ? (__typeof__(0 ? (double *)0 : \
                (void *)!((!__IS_FP(x) || !__IS_FP(y) || !__IS_FP(z)) && __FLT((x)+(y)+(z)+1.0f))))0 : \


@@ -55,6 +57,8 @@ sizeof(double) == sizeof(long double)
 #define __RETCAST_3(x, y, z)
 #endif
 
 #define __RETCAST_3(x, y, z)
 #endif
 

+/* function selection */
+

 #define __tg_real(fun, x) (__RETCAST(x)( \
        __FLT(x) ? fun ## f (x) : \
        __LDBL(x) ? fun ## l (x) : \
 #define __tg_real(fun, x) (__RETCAST(x)( \
        __FLT(x) ? fun ## f (x) : \
        __LDBL(x) ? fun ## l (x) : \