re PR c/7411 (cistore.c:392: Internal compiler error in instantiate_virtual_regs_1, at function.c:3974)

 PR c/7411
 * expr.c (expand_expr) [PLUS]: Simplify after the operands
 have been expanded in EXPAND_NORMAL mode.

Co-Authored-By: Volker Reichelt <reichelt@igpm.rwth-aachen.de>

From-SVN: r57882