[newlib-cygwin] newlib/libm/common: Don't re-convert float to bits in modf/modff

[newlib-cygwin] newlib/libm/common: Don't re-convert float to bits in modf/modff

[Corinna Vinschen]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=3439f3b0e998fd59f4ed277bb0c05bf24d7dc831

commit 3439f3b0e998fd59f4ed277bb0c05bf24d7dc831
Author: Keith Packard via Newlib <newlib@sourceware.org>
Date:   Wed Mar 25 17:18:20 2020 -0700

    newlib/libm/common: Don't re-convert float to bits in modf/modff
    
    These functions shared a pattern of re-converting the argument to bits
    when returning +/-0. Skip that as the initial conversion still has the
    sign bit.
    
    Signed-off-by: Keith Packard <keithp@keithp.com>

Diff:
---
 newlib/libm/common/s_modf.c  | 12 +++---------
 newlib/libm/common/sf_modf.c |  8 ++------
 2 files changed, 5 insertions(+), 15 deletions(-)

diff --git a/newlib/libm/common/s_modf.c b/newlib/libm/common/s_modf.c
index c826580b4..e552a9460 100644
--- a/newlib/libm/common/s_modf.c
+++ b/newlib/libm/common/s_modf.c
@@ -81,10 +81,8 @@ QUICKREF
 	    } else {
 		i = (0x000fffff)>>j0;
 		if(((i0&i)|i1)==0) {		/* x is integral */
-		    __uint32_t high;
 		    *iptr = x;
-		    GET_HIGH_WORD(high,x);
-		    INSERT_WORDS(x,high&0x80000000,0);	/* return +-0 */
+		    INSERT_WORDS(x,i0&0x80000000,0);	/* return +-0 */
 		    return x;
 		} else {
 		    INSERT_WORDS(*iptr,i0&(~i),0);
@@ -92,19 +90,15 @@ QUICKREF
 		}
 	    }
 	} else if (j0>51) {		/* no fraction part */
-	    __uint32_t high;
 	    *iptr = x;
 	    if (__fpclassifyd(x) == FP_NAN) return *iptr = x+x; /* x is NaN, return NaN */
-	    GET_HIGH_WORD(high,x);
-	    INSERT_WORDS(x,high&0x80000000,0);	/* return +-0 */
+	    INSERT_WORDS(x,i0&0x80000000,0);	/* return +-0 */
 	    return x;
 	} else {			/* fraction part in low x */
 	    i = ((__uint32_t)(0xffffffff))>>(j0-20);
 	    if((i1&i)==0) { 		/* x is integral */
-	        __uint32_t high;
 		*iptr = x;
-		GET_HIGH_WORD(high,x);
-		INSERT_WORDS(x,high&0x80000000,0);	/* return +-0 */
+		INSERT_WORDS(x,i0&0x80000000,0);	/* return +-0 */
 		return x;
 	    } else {
 	        INSERT_WORDS(*iptr,i0,i1&(~i));
diff --git a/newlib/libm/common/sf_modf.c b/newlib/libm/common/sf_modf.c
index e241e4612..2994378bb 100644
--- a/newlib/libm/common/sf_modf.c
+++ b/newlib/libm/common/sf_modf.c
@@ -33,10 +33,8 @@
 	    } else {
 		i = (0x007fffff)>>j0;
 		if((i0&i)==0) {			/* x is integral */
-		    __uint32_t ix;
 		    *iptr = x;
-		    GET_FLOAT_WORD(ix,x);
-		    SET_FLOAT_WORD(x,ix&0x80000000);	/* return +-0 */
+		    SET_FLOAT_WORD(x,i0&0x80000000);	/* return +-0 */
 		    return x;
 		} else {
 		    SET_FLOAT_WORD(*iptr,i0&(~i));
@@ -44,11 +42,9 @@
 		}
 	    }
 	} else {			/* no fraction part */
-	    __uint32_t ix;
 	    *iptr = x;
 	    if (__fpclassifyf(x) == FP_NAN) return *iptr = x+x; /* x is NaN, return NaN */
-	    GET_FLOAT_WORD(ix,x);
-	    SET_FLOAT_WORD(x,ix&0x80000000);	/* return +-0 */
+	    SET_FLOAT_WORD(x,i0&0x80000000);	/* return +-0 */
 	    return x;
 	}
 }