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Re: Patch to fix emit_library_call_value_1 for const functions
> On Tue, Apr 04, 2000 at 09:29:53PM +0200, Jan Hubicka wrote:
> > + if (flags & (ECF_CONST | ECF_PURE | ECF_MALLOC))
> > + start_sequence ();
>
> I don't think you meant ECF_MALLOC here.
It is mostly meaningless (since ECF_MALLOC may not be set)
I only wanted to keep code in sync with expand_call. We use sequence
for malloc calls there to make them removable (I doubt it is usefull, but
we do that). It may be usefull for new operator.
>
> > ! valreg = (mem_value == 0 && outmode != VOIDmode
> > ! ? hard_libcall_value (outmode) : NULL_RTX),
> ...
> > - FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
> > + valreg,
>
> This is wrong. FUNCTION_ARG with VOIDmode does magic target-specific
> stuff, and has nothing to do with hard_libcall_value.
Oops! I see, I've replaced wrong arg. Silly.
I wonder why this didn't show up in the regression tests.
>
> > + /* Construct an "equal form" for the value which mentions all the
> > + arguments in order as well as the function name. */
> > + if (PUSH_ARGS_REVERSED)
> > + for (i = 0; i < nargs; i++)
>
> There's no point ordering the list based on PUSH_ARGS_REVERSED.
> Although I see that expand_call does. Though that's pointless too.
OK.
Here is updated patch. Ok to install?
Tue Apr 4 20:49:01 MET DST 2000 Jan Hubicka <jh@suse.cz>
(expand_call): Do not reverze args in "equal from" field.
(emit_library_call_value_1): Emit_libcall_block for const and pure
function.
Index: egcs/gcc/calls.c
===================================================================
RCS file: /cvs/gcc/egcs/gcc/calls.c,v
retrieving revision 1.116
diff -c -3 -p -r1.116 calls.c
*** calls.c 2000/04/07 17:44:14 1.116
--- calls.c 2000/04/08 13:00:51
*************** expand_call (exp, target, ignore)
*** 2829,2840 ****
/* Construct an "equal form" for the value which mentions all the
arguments in order as well as the function name. */
! if (PUSH_ARGS_REVERSED)
! for (i = 0; i < num_actuals; i++)
! note = gen_rtx_EXPR_LIST (VOIDmode, args[i].initial_value, note);
! else
! for (i = num_actuals - 1; i >= 0; i--)
! note = gen_rtx_EXPR_LIST (VOIDmode, args[i].initial_value, note);
note = gen_rtx_EXPR_LIST (VOIDmode, funexp, note);
insns = get_insns ();
--- 2829,2836 ----
/* Construct an "equal form" for the value which mentions all the
arguments in order as well as the function name. */
! for (i = 0; i < num_actuals; i++)
! note = gen_rtx_EXPR_LIST (VOIDmode, args[i].initial_value, note);
note = gen_rtx_EXPR_LIST (VOIDmode, funexp, note);
insns = get_insns ();
*************** emit_library_call_value_1 (retval, orgfu
*** 3197,3202 ****
--- 3193,3199 ----
int old_inhibit_defer_pop = inhibit_defer_pop;
rtx call_fusage = 0;
rtx mem_value = 0;
+ rtx valreg;
int pcc_struct_value = 0;
int struct_value_size = 0;
int flags = 0;
*************** emit_library_call_value_1 (retval, orgfu
*** 3279,3284 ****
--- 3276,3286 ----
count = 0;
+ /* Now we are about to start emitting insns that can be deleted
+ if a libcall is deleted. */
+ if (flags & ECF_CONST)
+ start_sequence ();
+
push_temp_slots ();
/* If there's a structure value address to be passed,
*************** emit_library_call_value_1 (retval, orgfu
*** 3655,3666 ****
NO_DEFER_POP;
}
- #if 0
- /* For version 1.37, try deleting this entirely. */
- if (! no_queue)
- emit_queue ();
- #endif
-
/* Any regs containing parms remain in use through the call. */
for (count = 0; count < nargs; count++)
{
--- 3657,3662 ----
*************** emit_library_call_value_1 (retval, orgfu
*** 3685,3691 ****
/* Don't allow popping to be deferred, since then
cse'ing of library calls could delete a call and leave the pop. */
NO_DEFER_POP;
!
/* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
will set inhibit_defer_pop to that value. */
/* The return type is needed to decide how many bytes the function pops.
--- 3681,3688 ----
/* Don't allow popping to be deferred, since then
cse'ing of library calls could delete a call and leave the pop. */
NO_DEFER_POP;
! valreg = (mem_value == 0 && outmode != VOIDmode
! ? hard_libcall_value (outmode) : NULL_RTX),
/* We pass the old value of inhibit_defer_pop + 1 to emit_call_1, which
will set inhibit_defer_pop to that value. */
/* The return type is needed to decide how many bytes the function pops.
*************** emit_library_call_value_1 (retval, orgfu
*** 3700,3711 ****
original_args_size.constant, args_size.constant,
struct_value_size,
FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
! mem_value == 0 && outmode != VOIDmode ? hard_libcall_value (outmode) : NULL_RTX,
old_inhibit_defer_pop + 1, call_fusage, flags);
/* Now restore inhibit_defer_pop to its actual original value. */
OK_DEFER_POP;
pop_temp_slots ();
/* Copy the value to the right place. */
--- 3697,3741 ----
original_args_size.constant, args_size.constant,
struct_value_size,
FUNCTION_ARG (args_so_far, VOIDmode, void_type_node, 1),
! valreg,
old_inhibit_defer_pop + 1, call_fusage, flags);
/* Now restore inhibit_defer_pop to its actual original value. */
OK_DEFER_POP;
+ /* If call is cse'able, make appropriate pair of reg-notes around it.
+ Test valreg so we don't crash; may safely ignore `const'
+ if return type is void. Disable for PARALLEL return values, because
+ we have no way to move such values into a pseudo register. */
+ if ((flags & ECF_CONST)
+ && valreg != 0 && GET_CODE (valreg) != PARALLEL)
+ {
+ rtx note = 0;
+ rtx temp = gen_reg_rtx (GET_MODE (valreg));
+ rtx insns;
+ int i;
+
+ /* Construct an "equal form" for the value which mentions all the
+ arguments in order as well as the function name. */
+ for (i = 0; i < nargs; i++)
+ note = gen_rtx_EXPR_LIST (VOIDmode, argvec[i].value, note);
+ note = gen_rtx_EXPR_LIST (VOIDmode, fun, note);
+
+ insns = get_insns ();
+ end_sequence ();
+
+ emit_libcall_block (insns, temp, valreg, note);
+
+ valreg = temp;
+ }
+ else if (flags & ECF_CONST)
+ {
+ /* Otherwise, just write out the sequence without a note. */
+ rtx insns = get_insns ();
+
+ end_sequence ();
+ emit_insns (insns);
+ }
pop_temp_slots ();
/* Copy the value to the right place. */