[Bug middle-end/19775] [3.4/4.0 regression] sqrt(pow(x,y)) != pow(x,y*0.5) (with -ffast-math)

["cvs-commit at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

------- Additional Comments From cvs-commit at gcc dot gnu dot org  2005-02-07 13:24 -------
Subject: Bug 19775

CVSROOT:	/cvs/gcc
Module name:	gcc
Changes by:	rguenth@gcc.gnu.org	2005-02-07 13:24:38

Modified files:
	gcc            : ChangeLog builtins.c 
	gcc/testsuite  : ChangeLog 
	gcc/testsuite/gcc.dg/torture: builtin-power-1.c 
	gcc/testsuite/gcc.dg: builtins-10.c 
Added files:
	gcc/testsuite/gcc.dg: builtins-47.c 

Log message:
	2005-02-07  Richard Guenther  <rguenth@gcc.gnu.org>
	
	PR middle-end/19775
	* builtins.c (fold_builtin_sqrt): Transform
	sqrt(pow(x,y)) to pow(fabs(x),y*0.5), not
	pow(x,y*0.5).
	
	* gcc.dg/torture/builtin-power-1.c: Disable test for
	invalid transformation.
	* gcc.dg/builtins-10.c: Likewise.  Disable one test we
	no longer optimize.
	* gcc.dg/builtins-47.c: New testcase.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ChangeLog.diff?cvsroot=gcc&r1=2.7408&r2=2.7409
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/builtins.c.diff?cvsroot=gcc&r1=1.415&r2=1.416
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/ChangeLog.diff?cvsroot=gcc&r1=1.4998&r2=1.4999
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/gcc.dg/torture/builtin-power-1.c.diff?cvsroot=gcc&r1=1.1&r2=1.2
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/gcc.dg/builtins-47.c.diff?cvsroot=gcc&r1=1.1&r2=1.2
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/gcc.dg/builtins-10.c.diff?cvsroot=gcc&r1=1.1&r2=1.2



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19775