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authorUlrich Drepper <drepper@redhat.com>2009-08-24 18:05:48 -0700
committerUlrich Drepper <drepper@redhat.com>2009-08-24 18:05:48 -0700
commitcf00cc00bc53ab26b23b810b4bfbdfb43262538a (patch)
tree3d09caa3ecb83249ccaa5e0f874b9128c1de78e7 /sysdeps
parentb42a214c1807dc596cf3647fc35a0eb42ccc7e68 (diff)
downloadglibc-cf00cc00bc53ab26b23b810b4bfbdfb43262538a.tar.gz
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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.
Diffstat (limited to 'sysdeps')
-rw-r--r--sysdeps/ieee754/dbl-64/wordsize-64/s_ceil.c67
-rw-r--r--sysdeps/x86_64/fpu/math_private.h17
2 files changed, 84 insertions, 0 deletions
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 0000000000..9123fdc7bd
--- /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 8f4b792e77..4be753654a 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 {								\