i386: Handle REG_EH_REGION note

i386: Handle REG_EH_REGION note

When we split:

(insn 18 17 76 2 (set (reg:SF 88 [ _19 ])
        (float:SF (mem/c:SI (symbol_ref:DI ("d") [flags 0x2]  <var_decl 0x7fd6d8290c60 d>) [1 d+0 S4 A32]))) "x.ii":4:20 170 {*floatsisf2}
     (expr_list:REG_EH_REGION (const_int 2 [0x2])
        (nil)))

to

(insn 94 17 18 2 (set (reg:V4SF 115)
        (vec_merge:V4SF (vec_duplicate:V4SF (float:SF (mem/c:SI (symbol_ref:DI ("d") [flags 0x2]  <var_decl 0x7f346837ac60 d>) [1 d+0 S4 A32])))
            (reg:V4SF 114)
            (const_int 1 [0x1]))) "x.ii":4:20 -1
     (nil))
(insn 18 94 76 2 (set (reg:SF 88 [ _19 ])
        (subreg:SF (reg:V4SF 115) 0)) "x.ii":4:20 112 {*movsf_internal}
     (expr_list:REG_EH_REGION (const_int 2 [0x2])
        (nil)))

we must copy the REG_EH_REGION note to the first insn and split the block
after the newly added insn.  The REG_EH_REGION on the second insn will be
removed later since it no longer traps.

gcc/

	PR target/89650
	* config/i386/i386.c (remove_partial_avx_dependency): Handle
	REG_EH_REGION note.

gcc/testsuite/

	PR target/89650
	* g++.target/i386/pr89650.C: New test.

From-SVN: r269694