From d626297e87e19251a284ea1e9360e831b48999ca Mon Sep 17 00:00:00 2001 From: mpf Date: Thu, 4 Sep 2014 08:32:05 +0000 Subject: [PATCH] Add target hook to override DWARF2 frame register size gcc/ * target.def (TARGET_DWARF_FRAME_REG_MODE): New target hook. * targhooks.c (default_dwarf_frame_reg_mode): New function. * targhooks.h (default_dwarf_frame_reg_mode): New prototype. * doc/tm.texi.in (TARGET_DWARF_FRAME_REG_MODE): Document. * doc/tm.texi: Regenerate. * dwarf2cfi.c (expand_builtin_init_dwarf_reg_sizes): Abstract mode selection logic to default_dwarf_frame_reg_mode. git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@214898 138bc75d-0d04-0410-961f-82ee72b054a4 Signed-off-by: Khem Raj Upstream-Status: Backport [gcc 5.0] --- gcc/ChangeLog | 10 ++++++++++ gcc/doc/tm.texi | 7 +++++++ gcc/doc/tm.texi.in | 2 ++ gcc/dwarf2cfi.c | 4 +--- gcc/target.def | 11 +++++++++++ gcc/targhooks.c | 13 +++++++++++++ gcc/targhooks.h | 1 + 7 files changed, 45 insertions(+), 3 deletions(-) Index: gcc-4.9.2/gcc/doc/tm.texi =================================================================== --- gcc-4.9.2.orig/gcc/doc/tm.texi +++ gcc-4.9.2/gcc/doc/tm.texi @@ -9017,6 +9017,13 @@ register in Dwarf. Otherwise, this hook If not defined, the default is to return @code{NULL_RTX}. @end deftypefn +@deftypefn {Target Hook} {enum machine_mode} TARGET_DWARF_FRAME_REG_MODE (int @var{regno}) +Given a register, this hook should return the mode which the +corresponding Dwarf frame register should have. This is normally +used to return a smaller mode than the raw mode to prevent call +clobbered parts of a register altering the frame register size +@end deftypefn + @deftypefn {Target Hook} void TARGET_INIT_DWARF_REG_SIZES_EXTRA (tree @var{address}) If some registers are represented in Dwarf-2 unwind information in multiple pieces, define this hook to fill in information about the Index: gcc-4.9.2/gcc/doc/tm.texi.in =================================================================== --- gcc-4.9.2.orig/gcc/doc/tm.texi.in +++ gcc-4.9.2/gcc/doc/tm.texi.in @@ -6745,6 +6745,8 @@ the target supports DWARF 2 frame unwind @hook TARGET_DWARF_REGISTER_SPAN +@hook TARGET_DWARF_FRAME_REG_MODE + @hook TARGET_INIT_DWARF_REG_SIZES_EXTRA @hook TARGET_ASM_TTYPE Index: gcc-4.9.2/gcc/dwarf2cfi.c =================================================================== --- gcc-4.9.2.orig/gcc/dwarf2cfi.c +++ gcc-4.9.2/gcc/dwarf2cfi.c @@ -271,11 +271,9 @@ expand_builtin_init_dwarf_reg_sizes (tre if (rnum < DWARF_FRAME_REGISTERS) { HOST_WIDE_INT offset = rnum * GET_MODE_SIZE (mode); - enum machine_mode save_mode = reg_raw_mode[i]; HOST_WIDE_INT size; + enum machine_mode save_mode = targetm.dwarf_frame_reg_mode (i); - if (HARD_REGNO_CALL_PART_CLOBBERED (i, save_mode)) - save_mode = choose_hard_reg_mode (i, 1, true); if (dnum == DWARF_FRAME_RETURN_COLUMN) { if (save_mode == VOIDmode) Index: gcc-4.9.2/gcc/target.def =================================================================== --- gcc-4.9.2.orig/gcc/target.def +++ gcc-4.9.2/gcc/target.def @@ -3218,6 +3218,17 @@ If not defined, the default is to return rtx, (rtx reg), hook_rtx_rtx_null) +/* Given a register return the mode of the corresponding DWARF frame + register. */ +DEFHOOK +(dwarf_frame_reg_mode, + "Given a register, this hook should return the mode which the\n\ +corresponding Dwarf frame register should have. This is normally\n\ +used to return a smaller mode than the raw mode to prevent call\n\ +clobbered parts of a register altering the frame register size", + enum machine_mode, (int regno), + default_dwarf_frame_reg_mode) + /* If expand_builtin_init_dwarf_reg_sizes needs to fill in table entries not corresponding directly to registers below FIRST_PSEUDO_REGISTER, this hook should generate the necessary Index: gcc-4.9.2/gcc/targhooks.c =================================================================== --- gcc-4.9.2.orig/gcc/targhooks.c +++ gcc-4.9.2/gcc/targhooks.c @@ -1438,6 +1438,19 @@ default_debug_unwind_info (void) return UI_NONE; } +/* Determine the correct mode for a Dwarf frame register that represents + register REGNO. */ + +enum machine_mode +default_dwarf_frame_reg_mode (int regno) +{ + enum machine_mode save_mode = reg_raw_mode[regno]; + + if (HARD_REGNO_CALL_PART_CLOBBERED (regno, save_mode)) + save_mode = choose_hard_reg_mode (regno, 1, true); + return save_mode; +} + /* To be used by targets where reg_raw_mode doesn't return the right mode for registers used in apply_builtin_return and apply_builtin_arg. */ Index: gcc-4.9.2/gcc/targhooks.h =================================================================== --- gcc-4.9.2.orig/gcc/targhooks.h +++ gcc-4.9.2/gcc/targhooks.h @@ -194,6 +194,7 @@ extern int default_label_align_max_skip extern int default_jump_align_max_skip (rtx); extern section * default_function_section(tree decl, enum node_frequency freq, bool startup, bool exit); +extern enum machine_mode default_dwarf_frame_reg_mode (int); extern enum machine_mode default_get_reg_raw_mode (int); extern void *default_get_pch_validity (size_t *);