Fix ldbl128ibm fmodl for subnormals.

(cherry picked from commit 34ae0b3270c67cae0c54ac98b693fdf7d010a206)

3 files changed, 26 insertions, 18 deletions

diff --git a/ChangeLog b/ChangeLog
index 833d639770..81b3b1c939 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -16,6 +16,13 @@
 	* sysdeps/mach/configure: Likewise.
 	* sysdeps/mach/hurd/configure: Likewise.
 
+2012-06-04  Adhemerval Zanella  <azanella@linux.vnet.ibm.com>
+
+	* sysdeps/ieee754/ldbl-128ibm/e_fmodl.c (__ieee754_fmodl): Fix
+	subnormal exponent extraction and add some __builtin_expect.
+	* sysdeps/ieee754/ldbl-128ibm/math_ldbl.h (ldbl_extract_mantissa):
+	Fix for subnormal mantissa calculation.
+
 2012-06-01  Joseph Myers  <joseph@codesourcery.com>
 
 	[BZ #14048]
diff --git a/sysdeps/ieee754/ldbl-128ibm/e_fmodl.c b/sysdeps/ieee754/ldbl-128ibm/e_fmodl.c
index 4ad59a0916..deddb85501 100644
--- a/sysdeps/ieee754/ldbl-128ibm/e_fmodl.c
+++ b/sysdeps/ieee754/ldbl-128ibm/e_fmodl.c
@@ -27,8 +27,8 @@ static const long double one = 1.0, Zero[] = {0.0, -0.0,};
 long double
 __ieee754_fmodl (long double x, long double y)
 {
-	int64_t n,hx,hy,hz,ix,iy,sx,i;
-	u_int64_t lx,ly,lz;
+	int64_t n,hx,hy,hz,ix,iy,sx;
+	u_int64_t lx,ly,lz, i;
 	int temp;
 
 	GET_LDOUBLE_WORDS64(hx,lx,x);
@@ -38,41 +38,42 @@ __ieee754_fmodl (long double x, long double y)
 	hy &= 0x7fffffffffffffffLL;		/* |y| */
 
     /* purge off exception values */
-	if((hy|(ly&0x7fffffffffffffff))==0||(hx>=0x7ff0000000000000LL)|| /* y=0,or x not finite */
-	  (hy>0x7ff0000000000000LL))	/* or y is NaN */
+	if(__builtin_expect((hy|(ly&0x7fffffffffffffff))==0 ||
+			    (hx>=0x7ff0000000000000LL)|| /* y=0,or x not finite */
+			    (hy>0x7ff0000000000000LL),0))	/* or y is NaN */
 	    return (x*y)/(x*y);
-	if(hx<=hy) {
+	if(__builtin_expect(hx<=hy,0)) {
 	    if((hx<hy)||(lx<ly)) return x;	/* |x|<|y| return x */
 	    if(lx==ly)
 		return Zero[(u_int64_t)sx>>63];	/* |x|=|y| return x*0*/
 	}
 
     /* determine ix = ilogb(x) */
-	if(hx<0x0010000000000000LL) {	/* subnormal x */
+	if(__builtin_expect(hx<0x0010000000000000LL,0)) {	/* subnormal x */
 	    if(hx==0) {
 		for (ix = -1043, i=lx; i>0; i<<=1) ix -=1;
 	    } else {
-		for (ix = -1022, i=hx<<19; i>0; i<<=1) ix -=1;
+		for (ix = -1022, i=(hx<<11); i>0; i<<=1) ix -=1;
 	    }
 	} else ix = (hx>>52)-0x3ff;
 
     /* determine iy = ilogb(y) */
-	if(hy<0x0010000000000000LL) {	/* subnormal y */
+	if(__builtin_expect(hy<0x0010000000000000LL,0)) {	/* subnormal y */
 	    if(hy==0) {
 		for (iy = -1043, i=ly; i>0; i<<=1) iy -=1;
 	    } else {
-		for (iy = -1022, i=hy<<19; i>0; i<<=1) iy -=1;
+		for (iy = -1022, i=(hy<<11); i>0; i<<=1) iy -=1;
 	    }
 	} else iy = (hy>>52)-0x3ff;
 
     /* Make the IBM extended format 105 bit mantissa look like the ieee854 112
-       bit mantissa so the following operatations will give the correct
+       bit mantissa so the following operations will give the correct
        result.  */
 	ldbl_extract_mantissa(&hx, &lx, &temp, x);
 	ldbl_extract_mantissa(&hy, &ly, &temp, y);
 
     /* set up {hx,lx}, {hy,ly} and align y to x */
-	if(ix >= -1022)
+	if(__builtin_expect(ix >= -1022, 1))
 	    hx = 0x0001000000000000LL|(0x0000ffffffffffffLL&hx);
 	else {		/* subnormal x, shift x to normal */
 	    n = -1022-ix;
@@ -84,7 +85,7 @@ __ieee754_fmodl (long double x, long double y)
 		lx = 0;
 	    }
 	}
-	if(iy >= -1022)
+	if(__builtin_expect(iy >= -1022, 1))
 	    hy = 0x0001000000000000LL|(0x0000ffffffffffffLL&hy);
 	else {		/* subnormal y, shift y to normal */
 	    n = -1022-iy;
@@ -118,7 +119,7 @@ __ieee754_fmodl (long double x, long double y)
 	    hx = hx+hx+(lx>>63); lx = lx+lx;
 	    iy -= 1;
 	}
-	if(iy>= -1022) {	/* normalize output */
+	if(__builtin_expect(iy>= -1022,0)) {	/* normalize output */
 	    x = ldbl_insert_mantissa((sx>>63), iy, hx, lx);
 	} else {		/* subnormal output */
 	    n = -1022 - iy;
diff --git a/sysdeps/ieee754/ldbl-128ibm/math_ldbl.h b/sysdeps/ieee754/ldbl-128ibm/math_ldbl.h
index d055d6597e..be9ac71cb0 100644
--- a/sysdeps/ieee754/ldbl-128ibm/math_ldbl.h
+++ b/sysdeps/ieee754/ldbl-128ibm/math_ldbl.h
@@ -6,20 +6,20 @@
 #include <ieee754.h>
   
 static inline void
-ldbl_extract_mantissa (int64_t *hi64, u_int64_t *lo64, int *exp, long double x)
+ldbl_extract_mantissa (int64_t *hi64, uint64_t *lo64, int *exp, long double x)
 {
   /* We have 105 bits of mantissa plus one implicit digit.  Since
      106 bits are representable we use the first implicit digit for
      the number before the decimal point and the second implicit bit
      as bit 53 of the mantissa.  */
-  unsigned long long hi, lo;
+  uint64_t hi, lo;
   int ediff;
   union ibm_extended_long_double eldbl;
   eldbl.d = x;
   *exp = eldbl.ieee.exponent - IBM_EXTENDED_LONG_DOUBLE_BIAS;
 
-  lo = ((long long)eldbl.ieee.mantissa2 << 32) | eldbl.ieee.mantissa3;
-  hi = ((long long)eldbl.ieee.mantissa0 << 32) | eldbl.ieee.mantissa1;
+  lo = ((int64_t)eldbl.ieee.mantissa2 << 32) | eldbl.ieee.mantissa3;
+  hi = ((int64_t)eldbl.ieee.mantissa0 << 32) | eldbl.ieee.mantissa1;
   /* If the lower double is not a denomal or zero then set the hidden
      53rd bit.  */
   if (eldbl.ieee.exponent2 > 0x001)
@@ -31,8 +31,8 @@ ldbl_extract_mantissa (int64_t *hi64, u_int64_t *lo64, int *exp, long double x)
       ediff = eldbl.ieee.exponent - eldbl.ieee.exponent2;
       if (ediff > 53)
 	lo = lo >> (ediff-53);
+      hi |= (1ULL << 52);
     }
-  hi |= (1ULL << 52);
   
   if ((eldbl.ieee.negative != eldbl.ieee.negative2)
       && ((eldbl.ieee.exponent2 != 0) && (lo != 0LL)))