[Bug target/84530] -mfunction-return=thunk does not work for simple_return_pop_internal insn

["hjl at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84530

--- Comment #6 from hjl at gcc dot gnu.org <hjl at gcc dot gnu.org> ---
Author: hjl
Date: Mon Apr 16 19:06:32 2018
New Revision: 259420

URL: https://gcc.gnu.org/viewcvs?rev=259420&root=gcc&view=rev
Log:
i386: Update -mfunction-return= for return with pop

When -mfunction-return= is used, simple_return_pop_internal should pop
return address into ECX register, adjust stack by bytes to pop from stack
and jump to the return thunk via ECX register.

Revision 257992 removed the bool argument from ix86_output_indirect_jmp.
Update comments to reflect it.

Tested on i686 and x86-64.

gcc/

        Backport from mainline
        2018-02-26  H.J. Lu  <hongjiu.lu@intel.com>

        * config/i386/i386.c (ix86_output_indirect_jmp): Update comments.

        2018-02-26  H.J. Lu  <hongjiu.lu@intel.com>

        PR target/84530
        * config/i386/i386-protos.h (ix86_output_indirect_jmp): Remove
        the bool argument.
        (ix86_output_indirect_function_return): New prototype.
        (ix86_split_simple_return_pop_internal): Likewise.
        * config/i386/i386.c (indirect_return_via_cx): New.
        (indirect_return_via_cx_bnd): Likewise.
        (indirect_thunk_name): Handle return va CX_REG.
        (output_indirect_thunk_function): Create alias for
        __x86_return_thunk_[re]cx and __x86_return_thunk_[re]cx_bnd.
        (ix86_output_indirect_jmp): Remove the bool argument.
        (ix86_output_indirect_function_return): New function.
        (ix86_split_simple_return_pop_internal): Likewise.
        * config/i386/i386.md (*indirect_jump): Don't pass false
        to ix86_output_indirect_jmp.
        (*tablejump_1): Likewise.
        (simple_return_pop_internal): Change it to define_insn_and_split.
        Call ix86_split_simple_return_pop_internal to split it for
        -mfunction-return=.
        (simple_return_indirect_internal): Call
        ix86_output_indirect_function_return instead of
        ix86_output_indirect_jmp.

gcc/testsuite/

        Backport from mainline
        2018-02-26  H.J. Lu  <hongjiu.lu@intel.com>

        PR target/84530
        * gcc.target/i386/ret-thunk-22.c: New test.
        * gcc.target/i386/ret-thunk-23.c: Likewise.
        * gcc.target/i386/ret-thunk-24.c: Likewise.
        * gcc.target/i386/ret-thunk-25.c: Likewise.
        * gcc.target/i386/ret-thunk-26.c: Likewise.

Added:
    branches/gcc-6-branch/gcc/testsuite/gcc.target/i386/ret-thunk-22.c
    branches/gcc-6-branch/gcc/testsuite/gcc.target/i386/ret-thunk-23.c
    branches/gcc-6-branch/gcc/testsuite/gcc.target/i386/ret-thunk-24.c
    branches/gcc-6-branch/gcc/testsuite/gcc.target/i386/ret-thunk-25.c
    branches/gcc-6-branch/gcc/testsuite/gcc.target/i386/ret-thunk-26.c
Modified:
    branches/gcc-6-branch/gcc/ChangeLog
    branches/gcc-6-branch/gcc/config/i386/i386-protos.h
    branches/gcc-6-branch/gcc/config/i386/i386.c
    branches/gcc-6-branch/gcc/config/i386/i386.md
    branches/gcc-6-branch/gcc/testsuite/ChangeLog