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authorJan Hubicka <jh@suse.cz>2000-04-20 12:20:38 +0000
committerJan Hubicka <hubicka@gcc.gnu.org>2000-04-20 12:20:38 +0000
commitf8a097cd17f2e2465f5bc98aff3f4eaf616a0f2c (patch)
tree50fa6bdd3ffc8c85f3db97c6eb39359d9d91b417 /gcc/calls.c
parent48d9ade562cf3cc077c60cb1f49436054b34a3c6 (diff)
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calls.c (expand_call): Avoid unnecesary precalculation and outgoing parameters space guarding for...
* calls.c (expand_call): Avoid unnecesary precalculation and outgoing parameters space guarding for sibling calls. (store_one_arg): Likewise. From-SVN: r33280
Diffstat (limited to 'gcc/calls.c')
-rw-r--r--gcc/calls.c166
1 files changed, 80 insertions, 86 deletions
diff --git a/gcc/calls.c b/gcc/calls.c
index e61fc8f..12dea75 100644
--- a/gcc/calls.c
+++ b/gcc/calls.c
@@ -2467,12 +2467,12 @@ expand_call (exp, target, ignore)
|| reg_mentioned_p (virtual_outgoing_args_rtx,
structure_value_addr))
&& (args_size.var
- || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)
- ))
+ || (!ACCUMULATE_OUTGOING_ARGS && args_size.constant)))
structure_value_addr = copy_to_reg (structure_value_addr);
/* Precompute any arguments as needed. */
- precompute_arguments (flags, num_actuals, args);
+ if (pass)
+ precompute_arguments (flags, num_actuals, args);
/* Now we are about to start emitting insns that can be deleted
if a libcall is deleted. */
@@ -2480,11 +2480,14 @@ expand_call (exp, target, ignore)
start_sequence ();
old_stack_allocated = stack_pointer_delta - pending_stack_adjust;
-
+ /* The argument block when performing a sibling call is the
+ incoming argument block. */
+ if (pass == 0)
+ argblock = virtual_incoming_args_rtx;
/* If we have no actual push instructions, or shouldn't use them,
make space for all args right now. */
- if (args_size.var != 0)
+ else if (args_size.var != 0)
{
if (old_stack_level == 0)
{
@@ -2519,24 +2522,24 @@ expand_call (exp, target, ignore)
{
if (ACCUMULATE_OUTGOING_ARGS)
{
- /* Since the stack pointer will never be pushed, it is possible
- for the evaluation of a parm to clobber something we have
- already written to the stack. Since most function calls on
- RISC machines do not use the stack, this is uncommon, but
- must work correctly.
+ /* Since the stack pointer will never be pushed, it is
+ possible for the evaluation of a parm to clobber
+ something we have already written to the stack.
+ Since most function calls on RISC machines do not use
+ the stack, this is uncommon, but must work correctly.
Therefore, we save any area of the stack that was already
- written and that we are using. Here we set up to do this by
- making a new stack usage map from the old one. The actual
- save will be done by store_one_arg.
+ written and that we are using. Here we set up to do this
+ by making a new stack usage map from the old one. The
+ actual save will be done by store_one_arg.
Another approach might be to try to reorder the argument
evaluations to avoid this conflicting stack usage. */
#ifndef OUTGOING_REG_PARM_STACK_SPACE
- /* Since we will be writing into the entire argument area, the
- map must be allocated for its entire size, not just the part
- that is the responsibility of the caller. */
+ /* Since we will be writing into the entire argument area,
+ the map must be allocated for its entire size, not just
+ the part that is the responsibility of the caller. */
needed += reg_parm_stack_space;
#endif
@@ -2547,7 +2550,8 @@ expand_call (exp, target, ignore)
highest_outgoing_arg_in_use = MAX (initial_highest_arg_in_use,
needed);
#endif
- stack_usage_map = (char *) alloca (highest_outgoing_arg_in_use);
+ stack_usage_map
+ = (char *) alloca (highest_outgoing_arg_in_use);
if (initial_highest_arg_in_use)
bcopy (initial_stack_usage_map, stack_usage_map,
@@ -2559,9 +2563,9 @@ expand_call (exp, target, ignore)
- initial_highest_arg_in_use));
needed = 0;
- /* The address of the outgoing argument list must not be copied
- to a register here, because argblock would be left pointing
- to the wrong place after the call to
+ /* The address of the outgoing argument list must not be
+ copied to a register here, because argblock would be left
+ pointing to the wrong place after the call to
allocate_dynamic_stack_space below. */
argblock = virtual_outgoing_args_rtx;
@@ -2590,63 +2594,53 @@ expand_call (exp, target, ignore)
else
argblock = push_block (GEN_INT (needed), 0, 0);
- /* We only really need to call `copy_to_reg' in the case where
- push insns are going to be used to pass ARGBLOCK to a function
- call in ARGS. In that case, the stack pointer changes value
- from the allocation point to the call point, and hence
- the value of VIRTUAL_OUTGOING_ARGS_RTX changes as well.
- But might as well always do it. */
+ /* We only really need to call `copy_to_reg' in the case
+ where push insns are going to be used to pass ARGBLOCK
+ to a function call in ARGS. In that case, the stack
+ pointer changes value from the allocation point to the
+ call point, and hence the value of
+ VIRTUAL_OUTGOING_ARGS_RTX changes as well. But might
+ as well always do it. */
argblock = copy_to_reg (argblock);
- }
- }
- }
- /* The argument block when performing a sibling call is the
- incoming argument block. */
- if (pass == 0)
- {
- rtx temp = plus_constant (arg_pointer_rtx,
- FIRST_PARM_OFFSET (current_function_decl));
- argblock = force_reg (Pmode, force_operand (temp, NULL_RTX));
- }
-
- if (ACCUMULATE_OUTGOING_ARGS)
- {
- /* The save/restore code in store_one_arg handles all cases except one:
- a constructor call (including a C function returning a BLKmode struct)
- to initialize an argument. */
- if (stack_arg_under_construction)
- {
+ /* The save/restore code in store_one_arg handles all
+ cases except one:
+ a constructor call (including a C function returning
+ a BLKmode struct) to initialize an argument. */
+ if (stack_arg_under_construction)
+ {
#ifndef OUTGOING_REG_PARM_STACK_SPACE
- rtx push_size = GEN_INT (reg_parm_stack_space + args_size.constant);
+ rtx push_size = GEN_INT (reg_parm_stack_space + args_size.constant);
#else
- rtx push_size = GEN_INT (args_size.constant);
+ rtx push_size = GEN_INT (args_size.constant);
#endif
- if (old_stack_level == 0)
- {
- emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
- old_pending_adj = pending_stack_adjust;
- pending_stack_adjust = 0;
- /* stack_arg_under_construction says whether a stack arg is
- being constructed at the old stack level. Pushing the stack
- gets a clean outgoing argument block. */
- old_stack_arg_under_construction = stack_arg_under_construction;
- stack_arg_under_construction = 0;
- /* Make a new map for the new argument list. */
- stack_usage_map = (char *)alloca (highest_outgoing_arg_in_use);
- bzero (stack_usage_map, highest_outgoing_arg_in_use);
- highest_outgoing_arg_in_use = 0;
+ if (old_stack_level == 0)
+ {
+ emit_stack_save (SAVE_BLOCK, &old_stack_level, NULL_RTX);
+ old_pending_adj = pending_stack_adjust;
+ pending_stack_adjust = 0;
+ /* stack_arg_under_construction says whether a stack arg is
+ being constructed at the old stack level. Pushing the stack
+ gets a clean outgoing argument block. */
+ old_stack_arg_under_construction = stack_arg_under_construction;
+ stack_arg_under_construction = 0;
+ /* Make a new map for the new argument list. */
+ stack_usage_map = (char *)alloca (highest_outgoing_arg_in_use);
+ bzero (stack_usage_map, highest_outgoing_arg_in_use);
+ highest_outgoing_arg_in_use = 0;
+ }
+ allocate_dynamic_stack_space (push_size, NULL_RTX, BITS_PER_UNIT);
+ }
+ /* If argument evaluation might modify the stack pointer, copy the
+ address of the argument list to a register. */
+ for (i = 0; i < num_actuals; i++)
+ if (args[i].pass_on_stack)
+ {
+ argblock = copy_addr_to_reg (argblock);
+ break;
+ }
}
- allocate_dynamic_stack_space (push_size, NULL_RTX, BITS_PER_UNIT);
}
- /* If argument evaluation might modify the stack pointer, copy the
- address of the argument list to a register. */
- for (i = 0; i < num_actuals; i++)
- if (args[i].pass_on_stack)
- {
- argblock = copy_addr_to_reg (argblock);
- break;
- }
}
compute_argument_addresses (args, argblock, num_actuals);
@@ -2709,7 +2703,7 @@ expand_call (exp, target, ignore)
#ifdef REG_PARM_STACK_SPACE
/* Save the fixed argument area if it's part of the caller's frame and
is clobbered by argument setup for this call. */
- if (ACCUMULATE_OUTGOING_ARGS)
+ if (ACCUMULATE_OUTGOING_ARGS && pass)
save_area = save_fixed_argument_area (reg_parm_stack_space, argblock,
&low_to_save, &high_to_save);
#endif
@@ -2722,7 +2716,7 @@ expand_call (exp, target, ignore)
for (i = 0; i < num_actuals; i++)
if (args[i].reg == 0 || args[i].pass_on_stack)
- store_one_arg (&args[i], argblock, flags & ECF_MAY_BE_ALLOCA,
+ store_one_arg (&args[i], argblock, flags,
args_size.var != 0, reg_parm_stack_space);
/* If we have a parm that is passed in registers but not in memory
@@ -2737,7 +2731,7 @@ expand_call (exp, target, ignore)
if (reg_parm_seen)
for (i = 0; i < num_actuals; i++)
if (args[i].partial != 0 && ! args[i].pass_on_stack)
- store_one_arg (&args[i], argblock, flags & ECF_MAY_BE_ALLOCA,
+ store_one_arg (&args[i], argblock, flags,
args_size.var != 0, reg_parm_stack_space);
#ifdef PREFERRED_STACK_BOUNDARY
@@ -3037,14 +3031,13 @@ expand_call (exp, target, ignore)
stack_usage_map = initial_stack_usage_map;
sibcall_failure = 1;
}
- else if (ACCUMULATE_OUTGOING_ARGS)
+ else if (ACCUMULATE_OUTGOING_ARGS && pass)
{
#ifdef REG_PARM_STACK_SPACE
if (save_area)
{
restore_fixed_argument_area (save_area, argblock,
high_to_save, low_to_save);
- sibcall_failure = 1;
}
#endif
@@ -3065,7 +3058,6 @@ expand_call (exp, target, ignore)
validize_mem (args[i].save_area),
GEN_INT (args[i].size.constant),
PARM_BOUNDARY);
- sibcall_failure = 1;
}
highest_outgoing_arg_in_use = initial_highest_arg_in_use;
@@ -3595,8 +3587,8 @@ emit_library_call_value_1 (retval, orgfun, value, fn_type, outmode, nargs, p)
{
if (ACCUMULATE_OUTGOING_ARGS)
{
- /* If this is being stored into a pre-allocated, fixed-size, stack
- area, save any previous data at that location. */
+ /* If this is being stored into a pre-allocated, fixed-size,
+ stack area, save any previous data at that location. */
#ifdef ARGS_GROW_DOWNWARD
/* stack_slot is negative, but we want to index stack_usage_map
@@ -3610,16 +3602,18 @@ emit_library_call_value_1 (retval, orgfun, value, fn_type, outmode, nargs, p)
for (i = lower_bound; i < upper_bound; i++)
if (stack_usage_map[i]
- /* Don't store things in the fixed argument area at this point;
- it has already been saved. */
+ /* Don't store things in the fixed argument area at this
+ point; it has already been saved. */
&& i > reg_parm_stack_space)
break;
if (i != upper_bound)
{
- /* We need to make a save area. See what mode we can make it. */
+ /* We need to make a save area. See what mode we can make
+ it. */
enum machine_mode save_mode
- = mode_for_size (argvec[argnum].size.constant * BITS_PER_UNIT,
+ = mode_for_size (argvec[argnum].size.constant
+ * BITS_PER_UNIT,
MODE_INT, 1);
rtx stack_area
= gen_rtx_MEM
@@ -3975,11 +3969,11 @@ target_for_arg (type, size, args_addr, offset)
FNDECL is the declaration of the function we are calling. */
static void
-store_one_arg (arg, argblock, may_be_alloca, variable_size,
+store_one_arg (arg, argblock, flags, variable_size,
reg_parm_stack_space)
struct arg_data *arg;
rtx argblock;
- int may_be_alloca;
+ int flags;
int variable_size ATTRIBUTE_UNUSED;
int reg_parm_stack_space;
{
@@ -3996,7 +3990,7 @@ store_one_arg (arg, argblock, may_be_alloca, variable_size,
this argument. */
push_temp_slots ();
- if (ACCUMULATE_OUTGOING_ARGS)
+ if (ACCUMULATE_OUTGOING_ARGS && !(flags & ECF_SIBCALL))
{
/* If this is being stored into a pre-allocated, fixed-size, stack area,
save any previous data at that location. */
@@ -4124,7 +4118,7 @@ store_one_arg (arg, argblock, may_be_alloca, variable_size,
/* Don't allow anything left on stack from computation
of argument to alloca. */
- if (may_be_alloca)
+ if (flags & ECF_MAY_BE_ALLOCA)
do_pending_stack_adjust ();
if (arg->value == arg->stack)