> DJ Delorie writes:
> > JUMP_ALIGN_MAX_SKIP
> > LABEL_ALIGN_AFTER_BARRIER_MAX_SKIP
> > LOOP_ALIGN_MAX_SKIP
> > LABEL_ALIGN_MAX_SKIP
> >
> > None of these macros take any parameters, but for optimal performance
> > on RX, it's key to match the max_skip with the size of the following
> > opcode - there's a penalty only if you branch to an opcode which spans
> > fetch groups, but it's the same penalty as running a NOP opcode, so
> > you don't want to add nops if you don't have to.
> >
> > Can we extend those macros to take the label as a parameter? From
> > that, the backend could find the next actual insn.
>
> Seems fine to me. Looks like none of the existing targets define them
> directly anyhow.
>
> If you do this, though, turn them into target hooks. They are currently
> fields in target_flag_state.
How's this?
* doc/tm.texi.in (TARGET_ASM_JUMP_ALIGN_MAX_SKIP): New.
(TARGET_ASM_LABEL_ALIGN_AFTER_BARRIER_MAX_SKIP): Change to hook.
(TARGET_ASM_LOOP_ALIGN_MAX_SKIP): Likewise.
(TARGET_ASM_LABEL_ALIGN_MAX_SKIP): Likewise.
* targhooks.h (default_label_align_after_barrier_max_skip,
default_loop_align_max_skip, default_label_align_max_skip,
default_jump_align_max_skip): Declare.
* target.def (label_align_after_barrier_max_skip): New.
(loop_align_max_skip): New.
(label_align_max_skip): New.
(jump_align_max_skip): New.
* final.c (LABEL_ALIGN_MAX_SKIP): Remove.
(LOOP_ALIGN_MAX_SKIP): Remove.
(LABEL_ALIGN_AFTER_BARRIER_MAX_SKIP): Remove.
(JUMP_ALIGN_MAX_SKIP): Remove.
(default_label_align_after_barrier_max_skip): New.
(default_loop_align_max_skip): New.
(default_label_align_max_skip): New.
(default_jump_align_max_skip): New.
(compute_alignments): Use the new hooks.
(shorten_branches): Likewise.
Index: doc/tm.texi.in
===
--- doc/tm.texi.in (revision 164701)
+++ doc/tm.texi.in (working copy)
@@ -8893,26 +8893,32 @@ define the macro.
Unless it's necessary to inspect the @var{label} parameter, it is better
to set the variable @var{align_jumps} in the target's
@code{TARGET_OPTION_OVERRIDE}. Otherwise, you should try to honor the user's
selection in @var{align_jumps} in a @code{JUMP_ALIGN} implementation.
@end defmac
+...@hook TARGET_ASM_JUMP_ALIGN_MAX_SKIP
+The maximum number of bytes to skip before @var{label} when applying
+...@code{jump_align}. This works only if
+...@code{asm_output_max_skip_align} is defined.
+...@end deftypefn
+
@defmac LABEL_ALIGN_AFTER_BARRIER (@var{label})
The alignment (log base 2) to put in front of @var{label}, which follows
a @code{BARRIER}.
This macro need not be defined if you don't want any special alignment
to be done at such a time. Most machine descriptions do not currently
define the macro.
@end defmac
-...@defmac LABEL_ALIGN_AFTER_BARRIER_MAX_SKIP
-The maximum number of bytes to skip when applying
+...@hook TARGET_ASM_LABEL_ALIGN_AFTER_BARRIER_MAX_SKIP
+The maximum number of bytes to skip before @var{label} when applying
@code{LABEL_ALIGN_AFTER_BARRIER}. This works only if
@code{ASM_OUTPUT_MAX_SKIP_ALIGN} is defined.
-...@end defmac
+...@end deftypefn
@defmac LOOP_ALIGN (@var{label})
The alignment (log base 2) to put in front of @var{label}, which follows
a @code{NOTE_INSN_LOOP_BEG} note.
This macro need not be defined if you don't want any special alignment
@@ -8922,32 +8928,34 @@ define the macro.
Unless it's necessary to inspect the @var{label} parameter, it is better
to set the variable @code{align_loops} in the target's
@code{TARGET_OPTION_OVERRIDE}. Otherwise, you should try to honor the user's
selection in @code{align_loops} in a @code{LOOP_ALIGN} implementation.
@end defmac
-...@defmac LOOP_ALIGN_MAX_SKIP
-The maximum number of bytes to skip when applying @code{LOOP_ALIGN}.
-This works only if @code{ASM_OUTPUT_MAX_SKIP_ALIGN} is defined.
-...@end defmac
+...@hook TARGET_ASM_LOOP_ALIGN_MAX_SKIP
+The maximum number of bytes to skip when applying @code{LOOP_ALIGN} to
+...@var{label}. This works only if @code{ASM_OUTPUT_MAX_SKIP_ALIGN} is
+defined.
+...@end deftypefn
@defmac LABEL_ALIGN (@var{label})
The alignment (log base 2) to put in front of @var{label}.
If @code{LABEL_ALIGN_AFTER_BARRIER} / @code{LOOP_ALIGN} specify a different
alignment,
the maximum of the specified values is used.
Unless it's necessary to inspect the @var{label} parameter, it is better
to set the variable @code{align_labels} in the target's
@code{TARGET_OPTION_OVERRIDE}. Otherwise, you should try to honor the user's
selection in @code{align_labels} in a @code{LABEL_ALIGN} implementation.
@end defmac
-...@defmac LABEL_ALIGN_MAX_SKIP
-The maximum number of bytes to skip when applying @code{LABEL_ALIGN}.
-This works only if @code{ASM_OUTPUT_MAX_SKIP_ALIGN} is defined.
-...@end defmac
+...@hook TARG
