Aldy Hernandez <al...@redhat.com> writes:
> diff --git a/gcc/config/mips/mips.c b/gcc/config/mips/mips.c
> index b203cdd..5e98485 100644
> --- a/gcc/config/mips/mips.c
> +++ b/gcc/config/mips/mips.c
> @@ -16313,7 +16313,26 @@ mips_set_mips16_mode (int mips16_p)
> if (mips16_p)
> {
> if (!mips16_globals)
> - mips16_globals = save_target_globals ();
> + {
> + if (optimization_current_node != optimization_default_node)
> + {
> + tree opts = optimization_current_node;
> + /* Temporarily switch to the default optimization node,
> + so that *this_target_optabs is set to the default,
> + not reflecting whatever the first mips16 function
> + uses for the optimize attribute. */
> + optimization_current_node = optimization_default_node;
> + cl_optimization_restore
> + (&global_options,
> + TREE_OPTIMIZATION (optimization_default_node));
> + mips16_globals = save_target_globals ();
> + optimization_current_node = opts;
> + cl_optimization_restore (&global_options,
> + TREE_OPTIMIZATION (opts));
> + }
> + else
> + mips16_globals = save_target_globals ();
> + }
I think this should go in target-globals.c, maybe as
save_target_globals_default_opts.
> diff --git a/gcc/function.c b/gcc/function.c
> index 4ce2259..c5eea2e 100644
> --- a/gcc/function.c
> +++ b/gcc/function.c
> @@ -4400,6 +4400,31 @@ invoke_set_current_function_hook (tree fndecl)
> }
>
> targetm.set_current_function (fndecl);
> +
> + if (opts == optimization_default_node)
> + this_fn_optabs = this_target_optabs;
> + else
> + {
> + struct function *fn = DECL_STRUCT_FUNCTION (fndecl);
> + if (fn->optabs == NULL)
> + {
> + if (!SWITCHABLE_TARGET)
> + fn->optabs = TREE_OPTIMIZATION_OPTABS (opts);
> + else
> + {
> + if (this_target_optabs == &default_target_optabs)
> + fn->optabs = TREE_OPTIMIZATION_OPTABS (opts);
> + else
> + {
> + fn->optabs = (unsigned char *)
> + ggc_alloc_atomic (sizeof (struct target_optabs));
> + init_all_optabs ((struct target_optabs *) fn->optabs);
> + }
> + }
Following on from Jakub's:
if (!SWITCHABLE_TARGET
|| this_target_optabs == &default_target_optabs)
fn->optabs = TREE_OPTIMIZATION_OPTABS (opts);
I'd prefer just:
if (this_target_optabs == &default_target_optabs)
fn->optabs = TREE_OPTIMIZATION_OPTABS (opts);
Looks good to me otherwise, thanks.
Sorry that SWITCHABLE_TARGETS has been so much hassle. TBH, like Jakub
says in the PR, I was hoping things like the optimize attribute could
use the target_globals stuff too. Today we just care about optabs,
but e.g. arm.c has:
if (TARGET_THUMB1 && optimize_size)
{
/* When optimizing for size on Thumb-1, it's better not
to use the HI regs, because of the overhead of
stacking them. */
for (regno = FIRST_HI_REGNUM;
regno <= LAST_HI_REGNUM; ++regno)
fixed_regs[regno] = call_used_regs[regno] = 1;
}
which affects other cached global state like IRA tables.
The rtx_costs also often depend on optimize_size, and are cached in
various places like expmed.c. E.g. for:
int
foo (int x, int y)
{
return x * 10;
}
the -O2 version on MIPS32 is:
sll $2,$4,1
sll $4,$4,3
j $31
addu $2,$2,$4
and the -Os version is:
li $2,10
j $31
mul $2,$4,$2
But even if an optimize attribute is added:
int __attribute__((optimize(2)))
foo (int x, int y)
{
return x * 10;
}
what you get depends on whether -Os or -O2 was passed on the command line.
The attribute doesn't affect things either way. The same thing happens
on x86_64.
So in the end I think we'll end up trying solve the same problem that
the SWITCHABLE_TARGETS stuff was trying to solve, but this time for
__attribute__((optimize)).
Richard
