svn commit: r213281 - head/lib/libc/amd64/gen

[Dimitry Andric]

Author: dim
Date: Wed Sep 29 21:20:29 2010
New Revision: 213281
URL: http://svn.freebsd.org/changeset/base/213281

Log:
  Apply the same workaround for clang to amd64's version of ldexp.c (as in
  r212976): order the incoming arguments to fscale as st(0), st(1), and
  mark temp2 volatile (only in case of compilation with clang) to force
  clang to pop it correctly.  No binary change when compiled with gcc.
  
  This fixes ldexp() when compiled with clang on amd64, which makes
  drand48() and friends work correctly again, and this in turn fixes
  perl's tempfile().
  
  Reported by:	Renato Botelho, Derek Tattersall
  Approved by:	rpaulo (mentor)

Modified:
  head/lib/libc/amd64/gen/ldexp.c

Modified: head/lib/libc/amd64/gen/ldexp.c
==============================================================================
--- head/lib/libc/amd64/gen/ldexp.c	Wed Sep 29 21:19:25 2010	(r213280)
+++ head/lib/libc/amd64/gen/ldexp.c	Wed Sep 29 21:20:29 2010	(r213281)
@@ -36,6 +36,8 @@ static char sccsid[] = "@(#)ldexp.c	8.1 
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
+#include <math.h>
+
 /*
  * ldexp(value, exp): return value * (2 ** exp).
  *
@@ -49,12 +51,16 @@ __FBSDID("$FreeBSD$");
 double
 ldexp (double value, int exp)
 {
-	double temp, texp, temp2;
+	double temp, texp;
+#ifdef __clang__
+	volatile
+#endif
+	double temp2;
 	texp = exp;
 #ifdef __GNUC__
 	__asm ("fscale "
-		: "=u" (temp2), "=t" (temp)
-		: "0" (texp), "1" (value));
+		: "=t" (temp), "=u" (temp2)
+		: "0" (value), "1" (texp));
 #else
 #error unknown asm
 #endif