backport: re PR rtl-optimization/52060 (Invalid constant simplification in combine...

backport: re PR rtl-optimization/52060 (Invalid constant simplification in combine with parallel result)

	Backported from mainline
	2012-02-07  Jakub Jelinek  <jakub@redhat.com>

	PR rtl-optimization/52060
	* combine.c (try_combine): Add i0src_copy and i0src_copy2 variables,
	copy i1src to i1src_copy whenever added_sets_2 && i1_feeds_i2_n already
	before i1dest -> i1src substitution in newpat, copy i0src to i0src_copy
	and/or i0src_copy2 when needed.

	* gcc.dg/torture/pr52060.c: New test.

From-SVN: r184061