[Bug target/104375] [x86] Failure to recognize bzhi pattern when shr is present

[crazylht at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104375

--- Comment #1 from Hongtao.liu <crazylht at gmail dot com> ---
backend has 

16550(define_insn "*bmi2_bzhi_<mode>3_2"
16551  [(set (match_operand:SWI48 0 "register_operand" "=r")
16552        (and:SWI48
16553          (plus:SWI48
16554            (ashift:SWI48 (const_int 1)
16555                          (match_operand:QI 2 "register_operand" "r"))
16556            (const_int -1))
16557          (match_operand:SWI48 1 "nonimmediate_operand" "rm")))
16558   (clobber (reg:CC FLAGS_REG))]
16559  "TARGET_BMI2"
16560  "bzhi\t{%<k>2, %1, %0|%0, %1, %<k>2}"
16561  [(set_attr "type" "bitmanip")
16562   (set_attr "prefix" "vex")
16563   (set_attr "mode" "<MODE>")])


But there's extra zero_extend in pattern match.

315Failed to match this instruction:
316(parallel [
317        (set (reg:DI 90)
318            (zero_extend:DI (and:SI (plus:SI (reg:SI 91)
319                        (const_int -1 [0xffffffffffffffff]))
320                    (subreg:SI (reg:DI 95) 0))))
321        (clobber (reg:CC 17 flags))
322    ])