On Tue, 6 Oct 2015, H.J. Lu wrote:
> On Tue, Oct 06, 2015 at 02:30:59PM +0200, Richard Biener wrote:
> > On Tue, Oct 6, 2015 at 1:43 PM, H.J. Lu <hongjiu...@intel.com> wrote:
> > > Since targetm.expand_to_rtl_hook may be called to switch ABI, it should
> > > be called for each function before expanding to RTL. Otherwise, we may
> > > use the stale information from compilation of the previous function.
> > > aggregate_value_p uses call_used_regs. aggregate_value_p is used by
> > > IPA and return value optimization, which are called before
> > > pass_expand::execute after RTL expansion starts. We need to call
> > > targetm.expand_to_rtl_hook early enough in cgraph_node::expand to make
> > > sure that everything is in sync when RTL expansion starts.
> > >
> > > Tested on Linux/x86-64. OK for trunk?
> >
> > Hmm, I think set_cfun hook should handle this. expand_to_rtl_hook shouldn't
> > mess with per-function stuff.
> >
> > Richard.
> >
>
> I am testig this patch. OK for trunk if there is no regresion?
>
>
> H.J.
> --
> ix86_maybe_switch_abi is called to late during RTL expansion and we
> use the stale information from compilation of the previous function.
> aggregate_value_p uses call_used_regs. aggregate_value_p is used by
> IPA and return value optimization, which are called before
> pass_expand::execute after RTL expansion starts. Instead,
> ix86_maybe_switch_abi should be merged with ix86_set_current_function.
>
> PR target/67850
> * config/i386/i386.c (ix86_set_current_function): Renamed
> to ...
> (ix86_set_current_function_1): This.
> (ix86_set_current_function): New. incorporate old
> ix86_set_current_function and ix86_maybe_switch_abi.
> (ix86_maybe_switch_abi): Removed.
> (TARGET_EXPAND_TO_RTL_HOOK): Likewise.
> ---
> gcc/config/i386/i386.c | 33 ++++++++++++++++++---------------
> 1 file changed, 18 insertions(+), 15 deletions(-)
>
> diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
> index d59b59b..a0adf3d 100644
> --- a/gcc/config/i386/i386.c
> +++ b/gcc/config/i386/i386.c
> @@ -6222,7 +6222,7 @@ ix86_reset_previous_fndecl (void)
> FNDECL. The argument might be NULL to indicate processing at top
> level, outside of any function scope. */
> static void
> -ix86_set_current_function (tree fndecl)
> +ix86_set_current_function_1 (tree fndecl)
> {
> /* Only change the context if the function changes. This hook is called
> several times in the course of compiling a function, and we don't want
> to
> @@ -6262,6 +6262,23 @@ ix86_set_current_function (tree fndecl)
> ix86_previous_fndecl = fndecl;
> }
>
> +static void
> +ix86_set_current_function (tree fndecl)
> +{
> + ix86_set_current_function_1 (fndecl);
> +
> + if (!cfun)
> + return;
I think you want to test !fndecl here. Why split this out at all?
The ix86_previous_fndecl caching should still work, no?
> + /* 64-bit MS and SYSV ABI have different set of call used registers.
> + Avoid expensive re-initialization of init_regs each time we switch
> + function context since this is needed only during RTL expansion. */
The comment is now wrong (and your bug shows it was wrong previously).
> + if (TARGET_64BIT
> + && (call_used_regs[SI_REG]
> + == (cfun->machine->call_abi == MS_ABI)))
> + reinit_regs ();
> +}
> +
>
> /* Return true if this goes in large data/bss. */
>
> @@ -7395,17 +7412,6 @@ ix86_call_abi_override (const_tree fndecl)
> cfun->machine->call_abi = ix86_function_abi (fndecl);
> }
>
> -/* 64-bit MS and SYSV ABI have different set of call used registers. Avoid
> - expensive re-initialization of init_regs each time we switch function
> context
> - since this is needed only during RTL expansion. */
> -static void
> -ix86_maybe_switch_abi (void)
> -{
> - if (TARGET_64BIT &&
> - call_used_regs[SI_REG] == (cfun->machine->call_abi == MS_ABI))
> - reinit_regs ();
> -}
> -
> /* Return 1 if pseudo register should be created and used to hold
> GOT address for PIC code. */
> bool
> @@ -53802,9 +53808,6 @@ ix86_operands_ok_for_move_multiple (rtx *operands,
> bool load,
> #undef TARGET_CAN_INLINE_P
> #define TARGET_CAN_INLINE_P ix86_can_inline_p
>
> -#undef TARGET_EXPAND_TO_RTL_HOOK
> -#define TARGET_EXPAND_TO_RTL_HOOK ix86_maybe_switch_abi
> -
> #undef TARGET_LEGITIMATE_ADDRESS_P
> #define TARGET_LEGITIMATE_ADDRESS_P ix86_legitimate_address_p
>
>
--
Richard Biener <rguent...@suse.de>
SUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Graham Norton, HRB
21284 (AG Nuernberg)
