PR tree-optimization/84235
* tree-ssa-scopedtables.c
(avail_exprs_stack::simplify_binary_operation): Fir MINUS_EXPR, punt
if the subtraction is performed in floating point type where NaNs are
honored. For *DIV_EXPR, punt for ALL_FRACT_MODE_Ps where we can't
build 1. Formatting fix.
* gcc.c-torture/execute/ieee/pr84235.c: New test.
From-SVN: r257437
