From: Ulrich Drepper <drepper@redhat.com>
Date: Tue, 25 Aug 2009 01:05:48 +0000 (-0700)
Subject: Add ceil implementation for 64-bit machines.
X-Git-Tag: glibc-2.11~113
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=cf00cc00bc53ab26b23b810b4bfbdfb43262538a;p=platform%2Fupstream%2Fglibc.git

Add ceil implementation for 64-bit machines.

On 64-bit machines we should not split doubles into two 32 bit
integer and handle the words separately.  We have wide registers.
This patch implements a 64-bit ceil version.  Ideally all other
functions will be converted over time.
---

diff --git a/ChangeLog b/ChangeLog
index c29660d..b2d98e4 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,12 @@
 2009-08-24  Ulrich Drepper  <drepper@redhat.com>
 
+	* math/math_private.h (ieee_double_shape_type): Add uint64_t word to
+	union.
+	(EXTRACT_WORDS64, INSERT_WORDS64): Define.
+	* sysdeps/x86_64/fpu/math_private.h (EXTRACT_WORDS64, INSERT_WORDS64):
+	Redefine.
+	* sysdeps/ieee754/dbl-64/wordsize-64/s_ceil.c: New file.
+
 	* sysdeps/x86_64/fpu/math_private.h: Add specialized GET_FLOAT_WORD
 	and SET_FLOAT_WORD definitions.
 
diff --git a/math/math_private.h b/math/math_private.h
index 129646f..fade7e1 100644
--- a/math/math_private.h
+++ b/math/math_private.h
@@ -17,6 +17,7 @@
 #define _MATH_PRIVATE_H_
 
 #include <endian.h>
+#include <stdint.h>
 #include <sys/types.h>
 
 /* The original fdlibm code used statements like:
@@ -43,6 +44,7 @@ typedef union
     u_int32_t msw;
     u_int32_t lsw;
   } parts;
+  uint64_t word;
 } ieee_double_shape_type;
 
 #endif
@@ -57,6 +59,7 @@ typedef union
     u_int32_t lsw;
     u_int32_t msw;
   } parts;
+  uint64_t word;
 } ieee_double_shape_type;
 
 #endif
@@ -89,6 +92,14 @@ do {								\
   (i) = gl_u.parts.lsw;						\
 } while (0)
 
+/* Get all in one, efficient on 64-bit machines.  */
+#define EXTRACT_WORDS64(i,d)					\
+do {								\
+  ieee_double_shape_type gh_u;					\
+  gh_u.value = (d);						\
+  (i) = gh_u.word;						\
+} while (0)
+
 /* Set a double from two 32 bit ints.  */
 
 #define INSERT_WORDS(d,ix0,ix1)					\
@@ -99,6 +110,14 @@ do {								\
   (d) = iw_u.value;						\
 } while (0)
 
+/* Get all in one, efficient on 64-bit machines.  */
+#define INSERT_WORDS64(i,d)					\
+do {								\
+  ieee_double_shape_type iw_u;					\
+  iw_u.word = (i);						\
+  (d) = iw_u.value;						\
+} while (0)
+
 /* Set the more significant 32 bits of a double from an int.  */
 
 #define SET_HIGH_WORD(d,v)					\
diff --git a/sysdeps/ieee754/dbl-64/wordsize-64/s_ceil.c b/sysdeps/ieee754/dbl-64/wordsize-64/s_ceil.c
new file mode 100644
index 0000000..9123fdc
--- /dev/null
+++ b/sysdeps/ieee754/dbl-64/wordsize-64/s_ceil.c
@@ -0,0 +1,67 @@
+/* @(#)s_ceil.c 5.1 93/09/24 */
+/*
+ * ====================================================
+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ *
+ * Developed at SunPro, a Sun Microsystems, Inc. business.
+ * Permission to use, copy, modify, and distribute this
+ * software is freely granted, provided that this notice
+ * is preserved.
+ * ====================================================
+ */
+
+/*
+ * ceil(x)
+ * Return x rounded toward -inf to integral value
+ * Method:
+ *	Bit twiddling.
+ * Exception:
+ *	Inexact flag raised if x not equal to ceil(x).
+ */
+
+#include "math.h"
+#include "math_private.h"
+
+#ifdef __STDC__
+static const double huge = 1.0e300;
+#else
+static double huge = 1.0e300;
+#endif
+
+#ifdef __STDC__
+	double __ceil(double x)
+#else
+	double __ceil(x)
+	double x;
+#endif
+{
+	int64_t i0,i;
+	int32_t j0;
+	EXTRACT_WORDS64(i0,x);
+	j0 = ((i0>>52)&0x7ff)-0x3ff;
+	if(j0<=51) {
+	    if(j0<0) { 	/* raise inexact if x != 0 */
+		if(huge+x>0.0) {/* return 0*sign(x) if |x|<1 */
+		    if(i0<0) {i0=INT64_C(0x8000000000000000);}
+		    else if(i0!=0) { i0=INT64_C(0x3ff0000000000000);}
+		}
+	    } else {
+		i = INT64_C(0x000fffffffffffff)>>j0;
+		if((i0&i)==0) return x; /* x is integral */
+		if(huge+x>0.0) {	/* raise inexact flag */
+		    if(i0>0) i0 += UINT64_C(0x0010000000000000)>>j0;
+		    i0 &= (~i);
+		}
+	    }
+	} else {
+	    if(j0==0x400) return x+x;	/* inf or NaN */
+	    else return x;		/* x is integral */
+	}
+	INSERT_WORDS64(x,i0);
+	return x;
+}
+weak_alias (__ceil, ceil)
+#ifdef NO_LONG_DOUBLE
+strong_alias (__ceil, __ceill)
+weak_alias (__ceil, ceill)
+#endif
diff --git a/sysdeps/x86_64/fpu/math_private.h b/sysdeps/x86_64/fpu/math_private.h
index 8f4b792..4be7536 100644
--- a/sysdeps/x86_64/fpu/math_private.h
+++ b/sysdeps/x86_64/fpu/math_private.h
@@ -22,6 +22,23 @@ while (0)
 /* We can do a few things better on x86-64.  */
 
 /* Direct movement of float into integer register.  */
+#undef EXTRACT_WORDS64
+#define EXTRACT_WORDS64(i,d)					\
+do {								\
+  long int i_;							\
+  asm ("movd %1, %0" : "=rm" (i_) : "x" (d));			\
+  (i) = i_;							\
+} while (0)
+
+/* And the reverse.  */
+#undef INSERT_WORDS64
+#define INSERT_WORDS64(d,i) \
+do {								\
+  long int i_ = i;						\
+  asm ("movd %1, %0" : "=x" (d) : "rm" (i_));			\
+} while (0)
+
+/* Direct movement of float into integer register.  */
 #undef GET_FLOAT_WORD
 #define GET_FLOAT_WORD(i,d) \
 do {								\