Hello,
this is another tweak to the middle-end to help support the new
powerpc64le-linux ABI.
In the new ABI, we make a distinction between functions that pass
all arguments solely in registers, and those that do not. Only when
calling one the latter type (or a varags routine) does the caller
need to provide REG_PARM_STACK_SPACE; in the former case, this can
be omitted to save stack space.
This leads to a definition of REG_PARM_STACK_SPACE that is a lot
more complex than usual, which means it would be helpful if the
middle-end were to evaluate it sparingly (e.g. once per function
definition / call).
The middle-end already does cache REG_PARM_STACK_SPACE results,
however, this cache it not consistently used. In particular,
the locate_and_pad_parm routine will re-evaluate the macro
every time it is called, even though all callers of the routine
already have a cached copy.
This patch adds a new argument to locate_and_pad_parm which is
used instead of evaluating REG_PARM_STACK_SPACE, and updates
the callers to pass in the correct value.
There should be no change in generated code on any platform.
Tested on powerpc64-linux and powerpc64le-linux.
OK for mainline?
Bye,
Ulrich
2013-11-11 Ulrich Weigand <ulrich.weig...@de.ibm.com>
Alan Modra <amo...@gmail.com>
ChangeLog:
* function.c (assign_parms): Use all.reg_parm_stack_space instead
of re-evaluating REG_PARM_STACK_SPACE target macro.
(locate_and_pad_parm): New parameter REG_PARM_STACK_SPACE. Use it
instead of evaluating target macro REG_PARM_STACK_SPACE every time.
(assign_parm_find_entry_rtl): Update call.
* calls.c (initialize_argument_information): Update call.
(emit_library_call_value_1): Likewise.
* expr.h (locate_and_pad_parm): Update prototype.
Index: gcc/gcc/expr.h
===================================================================
--- gcc.orig/gcc/expr.h
+++ gcc/gcc/expr.h
@@ -521,8 +521,8 @@ extern rtx expand_divmod (int, enum tree
rtx, int);
#endif
-extern void locate_and_pad_parm (enum machine_mode, tree, int, int, tree,
- struct args_size *,
+extern void locate_and_pad_parm (enum machine_mode, tree, int, int, int,
+ tree, struct args_size *,
struct locate_and_pad_arg_data *);
/* Return the CODE_LABEL rtx for a LABEL_DECL, creating it if necessary. */
Index: gcc/gcc/calls.c
===================================================================
--- gcc.orig/gcc/calls.c
+++ gcc/gcc/calls.c
@@ -1326,6 +1326,7 @@ initialize_argument_information (int num
#else
args[i].reg != 0,
#endif
+ reg_parm_stack_space,
args[i].pass_on_stack ? 0 : args[i].partial,
fndecl, args_size, &args[i].locate);
#ifdef BLOCK_REG_PADDING
@@ -3736,7 +3737,8 @@ emit_library_call_value_1 (int retval, r
#else
argvec[count].reg != 0,
#endif
- 0, NULL_TREE, &args_size, &argvec[count].locate);
+ reg_parm_stack_space, 0,
+ NULL_TREE, &args_size, &argvec[count].locate);
if (argvec[count].reg == 0 || argvec[count].partial != 0
|| reg_parm_stack_space > 0)
@@ -3823,7 +3825,7 @@ emit_library_call_value_1 (int retval, r
#else
argvec[count].reg != 0,
#endif
- argvec[count].partial,
+ reg_parm_stack_space, argvec[count].partial,
NULL_TREE, &args_size, &argvec[count].locate);
args_size.constant += argvec[count].locate.size.constant;
gcc_assert (!argvec[count].locate.size.var);
Index: gcc/gcc/function.c
===================================================================
--- gcc.orig/gcc/function.c
+++ gcc/gcc/function.c
@@ -2523,6 +2523,7 @@ assign_parm_find_entry_rtl (struct assig
}
locate_and_pad_parm (data->promoted_mode, data->passed_type, in_regs,
+ all->reg_parm_stack_space,
entry_parm ? data->partial : 0, current_function_decl,
&all->stack_args_size, &data->locate);
@@ -3511,11 +3512,7 @@ assign_parms (tree fndecl)
/* Adjust function incoming argument size for alignment and
minimum length. */
-#ifdef REG_PARM_STACK_SPACE
- crtl->args.size = MAX (crtl->args.size,
- REG_PARM_STACK_SPACE (fndecl));
-#endif
-
+ crtl->args.size = MAX (crtl->args.size, all.reg_parm_stack_space);
crtl->args.size = CEIL_ROUND (crtl->args.size,
PARM_BOUNDARY / BITS_PER_UNIT);
@@ -3719,6 +3716,9 @@ gimplify_parameters (void)
IN_REGS is nonzero if the argument will be passed in registers. It will
never be set if REG_PARM_STACK_SPACE is not defined.
+ REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
+ for arguments which are passed in registers.
+
FNDECL is the function in which the argument was defined.
There are two types of rounding that are done. The first, controlled by
@@ -3739,19 +3739,16 @@ gimplify_parameters (void)
void
locate_and_pad_parm (enum machine_mode passed_mode, tree type, int in_regs,
- int partial, tree fndecl ATTRIBUTE_UNUSED,
+ int reg_parm_stack_space, int partial,
+ tree fndecl ATTRIBUTE_UNUSED,
struct args_size *initial_offset_ptr,
struct locate_and_pad_arg_data *locate)
{
tree sizetree;
enum direction where_pad;
unsigned int boundary, round_boundary;
- int reg_parm_stack_space = 0;
int part_size_in_regs;
-#ifdef REG_PARM_STACK_SPACE
- reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
-
/* If we have found a stack parm before we reach the end of the
area reserved for registers, skip that area. */
if (! in_regs)
@@ -3769,7 +3766,6 @@ locate_and_pad_parm (enum machine_mode p
initial_offset_ptr->constant = reg_parm_stack_space;
}
}
-#endif /* REG_PARM_STACK_SPACE */
part_size_in_regs = (reg_parm_stack_space == 0 ? partial : 0);
@@ -3832,11 +3828,7 @@ locate_and_pad_parm (enum machine_mode p
locate->slot_offset.constant += part_size_in_regs;
- if (!in_regs
-#ifdef REG_PARM_STACK_SPACE
- || REG_PARM_STACK_SPACE (fndecl) > 0
-#endif
- )
+ if (!in_regs || reg_parm_stack_space > 0)
pad_to_arg_alignment (&locate->slot_offset, boundary,
&locate->alignment_pad);
@@ -3856,11 +3848,7 @@ locate_and_pad_parm (enum machine_mode p
pad_below (&locate->offset, passed_mode, sizetree);
#else /* !ARGS_GROW_DOWNWARD */
- if (!in_regs
-#ifdef REG_PARM_STACK_SPACE
- || REG_PARM_STACK_SPACE (fndecl) > 0
-#endif
- )
+ if (!in_regs || reg_parm_stack_space > 0)
pad_to_arg_alignment (initial_offset_ptr, boundary,
&locate->alignment_pad);
locate->slot_offset = *initial_offset_ptr;
--
Dr. Ulrich Weigand
GNU/Linux compilers and toolchain
ulrich.weig...@de.ibm.com
