https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118266
--- Comment #16 from H.J. Lu <hjl.tools at gmail dot com> ---
ree turns:
(insn 27 26 139 2 (parallel [
(set (reg/f:SI 7 sp)
(plus:SI (reg/f:SI 7 sp)
(const_int 16 [0x10])))
(clobber (reg:CC 17 flags))
]) "x.ii":14:17 discrim 1 283 {*addsi_1}
(expr_list:REG_ARGS_SIZE (const_int 0 [0])
(nil)))
(insn 139 27 28 2 (set (reg/v:SI 42 r14 [orig:102 i ] [102])
(const_int 0 [0])) "x.ii":14:17 discrim 1 96 {*movsi_internal}
(expr_list:REG_EQUAL (const_int 0 [0])
(nil)))
(note 28 139 124 2 NOTE_INSN_DELETED)
(insn 124 28 125 2 (set (reg/f:SI 41 r13 [142])
(plus:SI (reg:SI 43 r15 [146])
(const_int 4 [0x4]))) 264 {*leasi}
(nil))
(insn 125 124 43 2 (set (reg/f:SI 40 r12 [143])
(plus:SI (reg:SI 43 r15 [146])
(const_int 8 [0x8]))) 264 {*leasi}
(nil))
(insn 43 125 74 2 (set (reg/f:DI 6 bp [145])
(zero_extend:DI (reg/f:SI 7 sp))) "x.ii":15:9 175 {*zero_extendsidi2}
(nil))
into
(insn 27 26 155 2 (parallel [
(set (reg:DI 6 bp)
(zero_extend:DI (plus:SI (reg/f:SI 7 sp)
(const_int 16 [0x10]))))
(clobber (reg:CC 17 flags))
]) "x.ii":14:17 discrim 1 296 {addsi_1_zext}
(expr_list:REG_ARGS_SIZE (const_int 0 [0])
(nil)))
(insn 155 27 139 2 (set (reg:DI 7 sp)
(reg:DI 6 bp)) "x.ii":14:17 discrim 1 -1
(nil))
(insn 139 155 28 2 (set (reg/v:SI 42 r14 [orig:102 i ] [102])
(const_int 0 [0])) "x.ii":14:17 discrim 1 96 {*movsi_internal}
(expr_list:REG_EQUAL (const_int 0 [0])
(nil)))
(note 28 139 124 2 NOTE_INSN_DELETED)
(insn 124 28 125 2 (set (reg/f:SI 41 r13 [142])
(plus:SI (reg:SI 43 r15 [146])
(const_int 4 [0x4]))) 264 {*leasi}
(nil))
(insn 125 124 74 2 (set (reg/f:SI 40 r12 [143])
(plus:SI (reg:SI 43 r15 [146])
(const_int 8 [0x8]))) 264 {*leasi}
(nil))
