Minor cleanups:

s_cosf.c and s_sinf.c:
Use a non-bogus magic constant for the threshold of pi/4.  It was 2 ulps
smaller than pi/4 rounded down, but its value is not critical so it should
be the result of natural rounding.

s_cosf.c and s_tanf.c:
Use a literal 0.0 instead of an unnecessary variable initialized to
[(float)]0.0.  Let the function prototype convert to 0.0F.

Improved wording in some comments.

Attempted to improve indentation of comments.

3 files changed, 21 insertions, 24 deletions

diff --git a/lib/msun/src/s_cosf.c b/lib/msun/src/s_cosf.c
index dd8a759..3a854b0 100644
--- a/lib/msun/src/s_cosf.c
+++ b/lib/msun/src/s_cosf.c
@@ -23,17 +23,16 @@ static char rcsid[] = "$FreeBSD$";
 float
 cosf(float x)
 {
-	float y[2],z=0.0;
+	float y[2];
 	int32_t n,ix;
 
 	GET_FLOAT_WORD(ix,x);
-
-    /* |x| ~< pi/4 */
 	ix &= 0x7fffffff;
-	if(ix <= 0x3f490fd8) {
-	    if(ix<0x39800000)			/* if x < 2**-12 */
-		if(((int)x)==0) return 1.0;	/* generate inexact */
-	    return __kernel_cosf(x,z);
+
+	if(ix <= 0x3f490fda) {		/* |x| ~<= pi/4 */
+	    if(ix<0x39800000)		/* |x| < 2**-12 */
+		if(((int)x)==0) return 1.0;	/* 1 with inexact if x != 0 */
+	    return __kernel_cosf(x,0.0);
 	}
 
     /* cos(Inf or NaN) is NaN */
diff --git a/lib/msun/src/s_sinf.c b/lib/msun/src/s_sinf.c
index a2485e8..7ddb8b6 100644
--- a/lib/msun/src/s_sinf.c
+++ b/lib/msun/src/s_sinf.c
@@ -23,17 +23,16 @@ static char rcsid[] = "$FreeBSD$";
 float
 sinf(float x)
 {
-	float y[2],z=0.0;
+	float y[2];
 	int32_t n, ix;
 
 	GET_FLOAT_WORD(ix,x);
-
-    /* |x| ~< pi/4 */
 	ix &= 0x7fffffff;
-	if(ix <= 0x3f490fd8) {
-	    if(ix<0x39800000)			/* if x < 2**-12 */
-		if(((int)x)==0) return x;	/* generate inexact */
-	    return __kernel_sinf(x,z,0);
+
+	if(ix <= 0x3f490fda) {		/* |x| ~<= pi/4 */
+	    if(ix<0x39800000)		/* |x| < 2**-12 */
+		if(((int)x)==0) return x;	/* x with inexact if x != 0 */
+	    return __kernel_sinf(x,0.0,0);
 	}
 
     /* sin(Inf or NaN) is NaN */
diff --git a/lib/msun/src/s_tanf.c b/lib/msun/src/s_tanf.c
index 81c84e4..7092226 100644
--- a/lib/msun/src/s_tanf.c
+++ b/lib/msun/src/s_tanf.c
@@ -23,26 +23,25 @@ static char rcsid[] = "$FreeBSD$";
 float
 tanf(float x)
 {
-	float y[2],z=0.0;
+	float y[2];
 	int32_t n, ix;
 
 	GET_FLOAT_WORD(ix,x);
-
-    /* |x| ~< pi/4 */
 	ix &= 0x7fffffff;
-	if(ix <= 0x3f490fda) {
-	    if(ix<0x39800000)			/* |x| < 2**-12 */
-		if(((int)x)==0) return x;	/* generate inexact */
-	    return __kernel_tanf(x,z,1);
+
+	if(ix <= 0x3f490fda) {		/* |x| ~<= pi/4 */
+	    if(ix<0x39800000)		/* |x| < 2**-12 */
+		if(((int)x)==0) return x;	/* x with inexact if x != 0 */
+	    return __kernel_tanf(x,0.0,1);
 	}
 
     /* tan(Inf or NaN) is NaN */
-	else if (ix>=0x7f800000) return x-x;		/* NaN */
+	else if (ix>=0x7f800000) return x-x;
 
     /* argument reduction needed */
 	else {
 	    n = __ieee754_rem_pio2f(x,y);
-	    return __kernel_tanf(y[0],y[1],1-((n&1)<<1)); /*   1 -- n even
-							      -1 -- n odd */
+	    /* integer parameter: 1 -- n even; -1 -- n odd */
+	    return __kernel_tanf(y[0],y[1],1-((n&1)<<1));
 	}
 }