Re: Turn HARD_REGNO_CALL_PART_CLOBBERED into a target hook

[Jeff Law]

On 08/28/2017 02:39 AM, Richard Sandiford wrote:
> The SVE patches change the size of a machine_mode from a compile-time
> constant to a runtime invariant.  However, target-specific code can
> continue to treat the modes as constant-sized if the target only has
> constant-sized modes.
> 
> The main snag with this approach is that target-independent code still
> uses macros from the target .h file.  This patch is one of several that
> converts a target macro to a hook.
> 
> Tested on aarch64-linux-gnu, x86_64-linux-gnu and powerpc64le-linux-gnu.
> Also tested by checking that there were no extra warnings or changes in
> testsuite assembly output for at least one target per CPU.  OK to install?
> 
> Richard
> 
> 
> 2017-08-28  Richard Sandiford  
>   Alan Hayward  
>   David Sherwood  
> 
> gcc/
>   * target.def (hard_regno_call_part_clobbered): New hook.
>   * doc/tm.texi.in (HARD_REGNO_CALL_PART_CLOBBERED): Replace with...
>   (TARGET_HARD_REGNO_CALL_PART_CLOBBERED): ...this hook.
>   * doc/tm.texi: Regenerate.
>   * hooks.h (hook_bool_uint_mode_false): Declare.
>   * hooks.c (hook_bool_uint_mode_false): New function.
>   * regs.h (HARD_REGNO_CALL_PART_CLOBBERED): Delete.
>   * cselib.c (cselib_process_insn): Use
>   targetm.hard_regno_call_part_clobbered instead of
>   HARD_REGNO_CALL_PART_CLOBBERED.
>   * ira-conflicts.c (ira_build_conflicts): Likewise.
>   * ira-costs.c (ira_tune_allocno_costs): Likewise.
>   * lra-constraints.c (need_for_call_save_p): Likewise.
>   * lra-lives.c: Include target.h.
>   (check_pseudos_live_through_calls): Use
>   targetm.hard_regno_call_part_clobbered instead of
>   HARD_REGNO_CALL_PART_CLOBBERED.
>   * regcprop.c: Include target.h.
>   (copyprop_hardreg_forward_1): Use
>   targetm.hard_regno_call_part_clobbered instead of
>   HARD_REGNO_CALL_PART_CLOBBERED.
>   * reginfo.c (choose_hard_reg_mode): Likewise.
>   * regrename.c (check_new_reg_p): Likewise.
>   * reload.c (find_equiv_reg): Likewise.
>   * reload1.c (emit_reload_insns): Likewise.
>   * sched-deps.c (deps_analyze_insn): Likewise.
>   * sel-sched.c (init_regs_for_mode): Likewise.
>   (mark_unavailable_hard_regs): Likewise.
>   * targhooks.c (default_dwarf_frame_reg_mode): Likewise.
>   * config/aarch64/aarch64.h (HARD_REGNO_CALL_PART_CLOBBERED): Delete.
>   * config/aarch64/aarch64.c (aarch64_hard_regno_call_part_clobbered):
>   New function.
>   (TARGET_HARD_REGNO_CALL_PART_CLOBBERED): Redefine.
>   * config/avr/avr.h (HARD_REGNO_CALL_PART_CLOBBERED): Delete.
>   * config/avr/avr-protos.h (avr_hard_regno_call_part_clobbered):
>   Delete.
>   * config/avr/avr.c (avr_hard_regno_call_part_clobbered): Make static
>   and return a bool.
>   (TARGET_HARD_REGNO_CALL_PART_CLOBBERED): Redefine.
>   * config/i386/i386.h (HARD_REGNO_CALL_PART_CLOBBERED): Delete.
>   * config/i386/i386.c (ix86_hard_regno_call_part_clobbered): New
>   function.
>   (TARGET_HARD_REGNO_CALL_PART_CLOBBERED): Redefine.
>   * config/mips/mips.h (HARD_REGNO_CALL_PART_CLOBBERED): Delete.
>   * config/mips/mips.c (mips_hard_regno_call_part_clobbered): New
>   function.
>   (TARGET_HARD_REGNO_CALL_PART_CLOBBERED): Redefine.
>   * config/powerpcspe/powerpcspe.h (HARD_REGNO_CALL_PART_CLOBBERED):
>   Delete.
>   * config/powerpcspe/powerpcspe.c
>   (rs6000_hard_regno_call_part_clobbered): New function.
>   (TARGET_HARD_REGNO_CALL_PART_CLOBBERED): Redefine.
>   * config/rs6000/rs6000.h (HARD_REGNO_CALL_PART_CLOBBERED): Delete.
>   * config/rs6000/rs6000.c (rs6000_hard_regno_call_part_clobbered):
>   New function.
>   (TARGET_HARD_REGNO_CALL_PART_CLOBBERED): Redefine.
>   * config/s390/s390.h (HARD_REGNO_CALL_PART_CLOBBERED): Delete.
>   * config/s390/s390.c (s390_hard_regno_call_part_clobbered): New
>   function.
>   (TARGET_HARD_REGNO_CALL_PART_CLOBBERED): Redefine.
>   * config/sh/sh.h (HARD_REGNO_CALL_PART_CLOBBERED): Delete.
>   * system.h (HARD_REGNO_CALL_PART_CLOBBERED): Poison.
OK.

jeff

Turn HARD_REGNO_CALL_PART_CLOBBERED into a target hook

[Richard Sandiford]

The SVE patches change the size of a machine_mode from a compile-time
constant to a runtime invariant.  However, target-specific code can
continue to treat the modes as constant-sized if the target only has
constant-sized modes.

The main snag with this approach is that target-independent code still
uses macros from the target .h file.  This patch is one of several that
converts a target macro to a hook.

Tested on aarch64-linux-gnu, x86_64-linux-gnu and powerpc64le-linux-gnu.
Also tested by checking that there were no extra warnings or changes in
testsuite assembly output for at least one target per CPU.  OK to install?

Richard


2017-08-28  Richard Sandiford  
Alan Hayward  
David Sherwood  

gcc/
* target.def (hard_regno_call_part_clobbered): New hook.
* doc/tm.texi.in (HARD_REGNO_CALL_PART_CLOBBERED): Replace with...
(TARGET_HARD_REGNO_CALL_PART_CLOBBERED): ...this hook.
* doc/tm.texi: Regenerate.
* hooks.h (hook_bool_uint_mode_false): Declare.
* hooks.c (hook_bool_uint_mode_false): New function.
* regs.h (HARD_REGNO_CALL_PART_CLOBBERED): Delete.
* cselib.c (cselib_process_insn): Use
targetm.hard_regno_call_part_clobbered instead of
HARD_REGNO_CALL_PART_CLOBBERED.
* ira-conflicts.c (ira_build_conflicts): Likewise.
* ira-costs.c (ira_tune_allocno_costs): Likewise.
* lra-constraints.c (need_for_call_save_p): Likewise.
* lra-lives.c: Include target.h.
(check_pseudos_live_through_calls): Use
targetm.hard_regno_call_part_clobbered instead of
HARD_REGNO_CALL_PART_CLOBBERED.
* regcprop.c: Include target.h.
(copyprop_hardreg_forward_1): Use
targetm.hard_regno_call_part_clobbered instead of
HARD_REGNO_CALL_PART_CLOBBERED.
* reginfo.c (choose_hard_reg_mode): Likewise.
* regrename.c (check_new_reg_p): Likewise.
* reload.c (find_equiv_reg): Likewise.
* reload1.c (emit_reload_insns): Likewise.
* sched-deps.c (deps_analyze_insn): Likewise.
* sel-sched.c (init_regs_for_mode): Likewise.
(mark_unavailable_hard_regs): Likewise.
* targhooks.c (default_dwarf_frame_reg_mode): Likewise.
* config/aarch64/aarch64.h (HARD_REGNO_CALL_PART_CLOBBERED): Delete.
* config/aarch64/aarch64.c (aarch64_hard_regno_call_part_clobbered):
New function.
(TARGET_HARD_REGNO_CALL_PART_CLOBBERED): Redefine.
* config/avr/avr.h (HARD_REGNO_CALL_PART_CLOBBERED): Delete.
* config/avr/avr-protos.h (avr_hard_regno_call_part_clobbered):
Delete.
* config/avr/avr.c (avr_hard_regno_call_part_clobbered): Make static
and return a bool.
(TARGET_HARD_REGNO_CALL_PART_CLOBBERED): Redefine.
* config/i386/i386.h (HARD_REGNO_CALL_PART_CLOBBERED): Delete.
* config/i386/i386.c (ix86_hard_regno_call_part_clobbered): New
function.
(TARGET_HARD_REGNO_CALL_PART_CLOBBERED): Redefine.
* config/mips/mips.h (HARD_REGNO_CALL_PART_CLOBBERED): Delete.
* config/mips/mips.c (mips_hard_regno_call_part_clobbered): New
function.
(TARGET_HARD_REGNO_CALL_PART_CLOBBERED): Redefine.
* config/powerpcspe/powerpcspe.h (HARD_REGNO_CALL_PART_CLOBBERED):
Delete.
* config/powerpcspe/powerpcspe.c
(rs6000_hard_regno_call_part_clobbered): New function.
(TARGET_HARD_REGNO_CALL_PART_CLOBBERED): Redefine.
* config/rs6000/rs6000.h (HARD_REGNO_CALL_PART_CLOBBERED): Delete.
* config/rs6000/rs6000.c (rs6000_hard_regno_call_part_clobbered):
New function.
(TARGET_HARD_REGNO_CALL_PART_CLOBBERED): Redefine.
* config/s390/s390.h (HARD_REGNO_CALL_PART_CLOBBERED): Delete.
* config/s390/s390.c (s390_hard_regno_call_part_clobbered): New
function.
(TARGET_HARD_REGNO_CALL_PART_CLOBBERED): Redefine.
* config/sh/sh.h (HARD_REGNO_CALL_PART_CLOBBERED): Delete.
* system.h (HARD_REGNO_CALL_PART_CLOBBERED): Poison.

Index: gcc/target.def
===
--- gcc/target.def  2017-08-28 09:36:09.610827107 +0100
+++ gcc/target.def  2017-08-28 09:36:10.075827140 +0100
@@ -5395,6 +5395,19 @@ The default version of this hook always
  bool, (unsigned int regno),
  default_hard_regno_scratch_ok)
 
+DEFHOOK
+(hard_regno_call_part_clobbered,
+ "This hook should return true if @var{regno} is partly call-saved and\n\
+partly call-clobbered, and if a value of mode @var{mode} would be partly\n\
+clobbered by a call.  For example, if the low 32 bits of @var{regno} are\n\
+preserved across a call but higher bits are clobbered, this hook should\n\
+return true for a 64-bit mode but false for a 32-bit mode.\n\
+\n\
+The default implementation returns false, which is correct\n\
+for targets