This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
ia64 eh, part 22
- To: gcc-patches at gcc dot gnu dot org
- Subject: ia64 eh, part 22
- From: Richard Henderson <rth at redhat dot com>
- Date: Wed, 28 Mar 2001 03:15:28 -0800
Update the x86 port for the changes to eh_return.
r~
* config/i386/i386.c (general_no_elim_operand): Disallow virtual regs.
(ix86_save_reg): If maybe_eh_return, true for EH_RETURN_DATA_REGNOs.
True for pic register if current_function_calls_eh_return.
(ix86_expand_epilogue): Change "emit_return" argument into "style".
Handle eh_return requirements.
* config/i386/i386.h (EH_RETURN_DATA_REGNO): New.
(EH_RETURN_STACKADJ_RTX): New.
* config/i386/i386.md (exception_receiver): Remove.
(eh_return, eh_return_1): New.
* config/i386/linux.h (MD_FALLBACK_FRAME_STATE_FOR): New.
Index: config/i386/i386.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/config/i386/i386.c,v
retrieving revision 1.243
diff -c -p -d -r1.243 i386.c
*** i386.c 2001/03/26 12:36:34 1.243
--- i386.c 2001/03/28 11:10:27
*************** static int ix86_split_to_parts PARAMS ((
*** 566,572 ****
static int ix86_safe_length_prefix PARAMS ((rtx));
static int ix86_nsaved_regs PARAMS((void));
static void ix86_emit_save_regs PARAMS((void));
! static void ix86_emit_restore_regs_using_mov PARAMS ((rtx, int));
static void ix86_emit_epilogue_esp_adjustment PARAMS((int));
static void ix86_set_move_mem_attrs_1 PARAMS ((rtx, rtx, rtx, rtx, rtx));
static void ix86_sched_reorder_pentium PARAMS((rtx *, rtx *));
--- 566,572 ----
static int ix86_safe_length_prefix PARAMS ((rtx));
static int ix86_nsaved_regs PARAMS((void));
static void ix86_emit_save_regs PARAMS((void));
! static void ix86_emit_restore_regs_using_mov PARAMS ((rtx, int, bool));
static void ix86_emit_epilogue_esp_adjustment PARAMS((int));
static void ix86_set_move_mem_attrs_1 PARAMS ((rtx, rtx, rtx, rtx, rtx));
static void ix86_sched_reorder_pentium PARAMS((rtx *, rtx *));
*************** static int ix86_fp_comparison_arithmetic
*** 606,612 ****
static int ix86_fp_comparison_fcomi_cost PARAMS ((enum rtx_code code));
static int ix86_fp_comparison_sahf_cost PARAMS ((enum rtx_code code));
static int ix86_fp_comparison_cost PARAMS ((enum rtx_code code));
! static int ix86_save_reg PARAMS ((int));
static void ix86_compute_frame_layout PARAMS ((struct ix86_frame *));
/* Sometimes certain combinations of command options do not make
--- 606,612 ----
static int ix86_fp_comparison_fcomi_cost PARAMS ((enum rtx_code code));
static int ix86_fp_comparison_sahf_cost PARAMS ((enum rtx_code code));
static int ix86_fp_comparison_cost PARAMS ((enum rtx_code code));
! static int ix86_save_reg PARAMS ((int, bool));
static void ix86_compute_frame_layout PARAMS ((struct ix86_frame *));
/* Sometimes certain combinations of command options do not make
*************** general_no_elim_operand (op, mode)
*** 1475,1480 ****
--- 1475,1484 ----
|| t == virtual_incoming_args_rtx || t == virtual_stack_vars_rtx
|| t == virtual_stack_dynamic_rtx)
return 0;
+ if (REG_P (t)
+ && REGNO (t) >= FIRST_VIRTUAL_REGISTER
+ && REGNO (t) <= LAST_VIRTUAL_REGISTER)
+ return 0;
return general_operand (op, mode);
}
*************** gen_push (arg)
*** 2249,2265 ****
/* Return 1 if we need to save REGNO. */
static int
! ix86_save_reg (regno)
! int regno;
{
! int pic_reg_used = flag_pic && (current_function_uses_pic_offset_table
! || current_function_uses_const_pool)
! && !TARGET_64BIT;
! return ((regs_ever_live[regno] && !call_used_regs[regno]
! && !fixed_regs[regno]
! && (regno != HARD_FRAME_POINTER_REGNUM || !frame_pointer_needed))
! || (regno == PIC_OFFSET_TABLE_REGNUM && pic_reg_used));
}
/* Return number of registers to be saved on the stack. */
--- 2253,2287 ----
/* Return 1 if we need to save REGNO. */
static int
! ix86_save_reg (regno, maybe_eh_return)
! int regno;
! bool maybe_eh_return;
{
! if (flag_pic
! && ! TARGET_64BIT
! && regno == PIC_OFFSET_TABLE_REGNUM
! && (current_function_uses_pic_offset_table
! || current_function_uses_const_pool
! || current_function_calls_eh_return))
! return 1;
+ if (current_function_calls_eh_return && maybe_eh_return)
+ {
+ unsigned i;
+ for (i = 0; ; i++)
+ {
+ unsigned test = EH_RETURN_DATA_REGNO(i);
+ if (test == INVALID_REGNUM)
+ break;
+ if (test == (unsigned) regno)
+ return 1;
+ }
+ }
+
+ return (regs_ever_live[regno]
+ && !call_used_regs[regno]
+ && !fixed_regs[regno]
+ && (regno != HARD_FRAME_POINTER_REGNUM || !frame_pointer_needed));
}
/* Return number of registers to be saved on the stack. */
*************** ix86_nsaved_regs ()
*** 2271,2277 ****
int regno;
for (regno = FIRST_PSEUDO_REGISTER - 1; regno >= 0; regno--)
! if (ix86_save_reg (regno))
nregs++;
return nregs;
}
--- 2293,2299 ----
int regno;
for (regno = FIRST_PSEUDO_REGISTER - 1; regno >= 0; regno--)
! if (ix86_save_reg (regno, true))
nregs++;
return nregs;
}
*************** ix86_emit_save_regs ()
*** 2423,2429 ****
rtx insn;
for (regno = FIRST_PSEUDO_REGISTER - 1; regno >= 0; regno--)
! if (ix86_save_reg (regno))
{
insn = emit_insn (gen_push (gen_rtx_REG (Pmode, regno)));
RTX_FRAME_RELATED_P (insn) = 1;
--- 2445,2451 ----
rtx insn;
for (regno = FIRST_PSEUDO_REGISTER - 1; regno >= 0; regno--)
! if (ix86_save_reg (regno, true))
{
insn = emit_insn (gen_push (gen_rtx_REG (Pmode, regno)));
RTX_FRAME_RELATED_P (insn) = 1;
*************** ix86_emit_epilogue_esp_adjustment (tsize
*** 2535,2548 ****
/* Emit code to restore saved registers using MOV insns. First register
is restored from POINTER + OFFSET. */
static void
! ix86_emit_restore_regs_using_mov (pointer, offset)
! rtx pointer;
! int offset;
{
int regno;
for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
! if (ix86_save_reg (regno))
{
emit_move_insn (gen_rtx_REG (Pmode, regno),
adj_offsettable_operand (gen_rtx_MEM (Pmode,
--- 2557,2571 ----
/* Emit code to restore saved registers using MOV insns. First register
is restored from POINTER + OFFSET. */
static void
! ix86_emit_restore_regs_using_mov (pointer, offset, maybe_eh_return)
! rtx pointer;
! int offset;
! bool maybe_eh_return;
{
int regno;
for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
! if (ix86_save_reg (regno, maybe_eh_return))
{
emit_move_insn (gen_rtx_REG (Pmode, regno),
adj_offsettable_operand (gen_rtx_MEM (Pmode,
*************** ix86_emit_restore_regs_using_mov (pointe
*** 2555,2562 ****
/* Restore function stack, frame, and registers. */
void
! ix86_expand_epilogue (emit_return)
! int emit_return;
{
int regno;
int sp_valid = !frame_pointer_needed || current_function_sp_is_unchanging;
--- 2578,2585 ----
/* Restore function stack, frame, and registers. */
void
! ix86_expand_epilogue (style)
! int style;
{
int regno;
int sp_valid = !frame_pointer_needed || current_function_sp_is_unchanging;
*************** ix86_expand_epilogue (emit_return)
*** 2588,2594 ****
if ((!sp_valid && frame.nregs <= 1)
|| (frame_pointer_needed && !frame.nregs && frame.to_allocate)
|| (frame_pointer_needed && TARGET_USE_LEAVE && !optimize_size
! && frame.nregs == 1))
{
/* Restore registers. We can use ebp or esp to address the memory
locations. If both are available, default to ebp, since offsets
--- 2611,2618 ----
if ((!sp_valid && frame.nregs <= 1)
|| (frame_pointer_needed && !frame.nregs && frame.to_allocate)
|| (frame_pointer_needed && TARGET_USE_LEAVE && !optimize_size
! && frame.nregs == 1)
! || style == 2)
{
/* Restore registers. We can use ebp or esp to address the memory
locations. If both are available, default to ebp, since offsets
*************** ix86_expand_epilogue (emit_return)
*** 2597,2608 ****
mode. */
if (!frame_pointer_needed || (sp_valid && !frame.to_allocate))
! ix86_emit_restore_regs_using_mov (stack_pointer_rtx, frame.to_allocate);
else
! ix86_emit_restore_regs_using_mov (hard_frame_pointer_rtx, offset);
! if (!frame_pointer_needed)
! ix86_emit_epilogue_esp_adjustment (frame.to_allocate + frame.nregs * UNITS_PER_WORD);
/* If not an i386, mov & pop is faster than "leave". */
else if (TARGET_USE_LEAVE || optimize_size)
emit_insn (TARGET_64BIT ? gen_leave_rex64 () : gen_leave ());
--- 2621,2661 ----
mode. */
if (!frame_pointer_needed || (sp_valid && !frame.to_allocate))
! ix86_emit_restore_regs_using_mov (stack_pointer_rtx,
! frame.to_allocate, style == 2);
else
! ix86_emit_restore_regs_using_mov (hard_frame_pointer_rtx,
! offset, style == 2);
! /* eh_return epilogues need %ecx added to the stack pointer. */
! if (style == 2)
! {
! rtx tmp, sa = EH_RETURN_STACKADJ_RTX;
!
! if (frame_pointer_needed)
! {
! tmp = gen_rtx_PLUS (Pmode, hard_frame_pointer_rtx, sa);
! tmp = plus_constant (tmp, UNITS_PER_WORD);
! emit_insn (gen_rtx_SET (VOIDmode, sa, tmp));
!
! tmp = gen_rtx_MEM (Pmode, hard_frame_pointer_rtx);
! emit_move_insn (hard_frame_pointer_rtx, tmp);
!
! emit_insn (gen_pro_epilogue_adjust_stack
! (stack_pointer_rtx, sa, const0_rtx,
! hard_frame_pointer_rtx));
! }
! else
! {
! tmp = gen_rtx_PLUS (Pmode, stack_pointer_rtx, sa);
! tmp = plus_constant (tmp, (frame.to_allocate
! + frame.nregs * UNITS_PER_WORD));
! emit_insn (gen_rtx_SET (VOIDmode, stack_pointer_rtx, tmp));
! }
! }
! else if (!frame_pointer_needed)
! ix86_emit_epilogue_esp_adjustment (frame.to_allocate
! + frame.nregs * UNITS_PER_WORD);
/* If not an i386, mov & pop is faster than "leave". */
else if (TARGET_USE_LEAVE || optimize_size)
emit_insn (TARGET_64BIT ? gen_leave_rex64 () : gen_leave ());
*************** ix86_expand_epilogue (emit_return)
*** 2635,2641 ****
ix86_emit_epilogue_esp_adjustment (frame.to_allocate);
for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
! if (ix86_save_reg (regno))
{
if (TARGET_64BIT)
emit_insn (gen_popdi1 (gen_rtx_REG (Pmode, regno)));
--- 2688,2694 ----
ix86_emit_epilogue_esp_adjustment (frame.to_allocate);
for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
! if (ix86_save_reg (regno, false))
{
if (TARGET_64BIT)
emit_insn (gen_popdi1 (gen_rtx_REG (Pmode, regno)));
*************** ix86_expand_epilogue (emit_return)
*** 2652,2658 ****
}
/* Sibcall epilogues don't want a return instruction. */
! if (! emit_return)
return;
if (current_function_pops_args && current_function_args_size)
--- 2705,2711 ----
}
/* Sibcall epilogues don't want a return instruction. */
! if (style == 0)
return;
if (current_function_pops_args && current_function_args_size)
Index: config/i386/i386.h
===================================================================
RCS file: /cvs/gcc/gcc/gcc/config/i386/i386.h,v
retrieving revision 1.172
diff -c -p -d -r1.172 i386.h
*** i386.h 2001/03/26 12:36:35 1.172
--- i386.h 2001/03/28 11:10:27
*************** extern int const svr4_dbx_register_map[F
*** 2779,2794 ****
gen_rtx_MEM (VOIDmode, gen_rtx_REG (VOIDmode, STACK_POINTER_REGNUM))
/* After the prologue, RA is at -4(AP) in the current frame. */
! #define RETURN_ADDR_RTX(COUNT, FRAME) \
! ((COUNT) == 0 \
! ? gen_rtx_MEM (Pmode, plus_constant (arg_pointer_rtx, TARGET_64BIT ? -8 : -4))\
! : gen_rtx_MEM (Pmode, plus_constant (FRAME, TARGET_64BIT ? 8 : 4)))
/* PC is dbx register 8; let's use that column for RA. */
#define DWARF_FRAME_RETURN_COLUMN (TARGET_64BIT ? 16 : 8)
/* Before the prologue, the top of the frame is at 4(%esp). */
#define INCOMING_FRAME_SP_OFFSET UNITS_PER_WORD
/* This is how to output the definition of a user-level label named NAME,
such as the label on a static function or variable NAME. */
--- 2779,2798 ----
gen_rtx_MEM (VOIDmode, gen_rtx_REG (VOIDmode, STACK_POINTER_REGNUM))
/* After the prologue, RA is at -4(AP) in the current frame. */
! #define RETURN_ADDR_RTX(COUNT, FRAME) \
! ((COUNT) == 0 \
! ? gen_rtx_MEM (Pmode, plus_constant (arg_pointer_rtx, -UNITS_PER_WORD)) \
! : gen_rtx_MEM (Pmode, plus_constant (FRAME, UNITS_PER_WORD)))
/* PC is dbx register 8; let's use that column for RA. */
#define DWARF_FRAME_RETURN_COLUMN (TARGET_64BIT ? 16 : 8)
/* Before the prologue, the top of the frame is at 4(%esp). */
#define INCOMING_FRAME_SP_OFFSET UNITS_PER_WORD
+
+ /* Describe how we implement __builtin_eh_return. */
+ #define EH_RETURN_DATA_REGNO(N) ((N) < 2 ? (N) : INVALID_REGNUM)
+ #define EH_RETURN_STACKADJ_RTX gen_rtx_REG (Pmode, 2)
/* This is how to output the definition of a user-level label named NAME,
such as the label on a static function or variable NAME. */
Index: config/i386/i386.md
===================================================================
RCS file: /cvs/gcc/gcc/gcc/config/i386/i386.md,v
retrieving revision 1.249
diff -c -p -d -r1.249 i386.md
*** i386.md 2001/03/26 13:56:34 1.249
--- i386.md 2001/03/28 11:10:27
***************
*** 73,78 ****
--- 73,79 ----
;; 10 This is a `sahf' operation.
;; 11 This is a `fstcw' operation
;; 12 This is behaviour of add when setting carry flag.
+ ;; 13 This is a `eh_return' placeholder.
;; For SSE/MMX support:
;; 30 This is `fix', guaranteed to be truncating.
***************
*** 13017,13022 ****
--- 13018,13052 ----
""
"ix86_expand_epilogue (0); DONE;")
+ (define_expand "eh_return"
+ [(use (match_operand 0 "register_operand" ""))
+ (use (match_operand 1 "register_operand" ""))]
+ ""
+ "
+ {
+ rtx tmp, sa = operands[0], ra = operands[1];
+
+ /* Tricky bit: we write the address of the handler to which we will
+ be returning into someone else's stack frame, one word below the
+ stack address we wish to restore. */
+ tmp = gen_rtx_PLUS (Pmode, arg_pointer_rtx, sa);
+ tmp = plus_constant (tmp, -UNITS_PER_WORD);
+ tmp = gen_rtx_MEM (Pmode, tmp);
+ emit_move_insn (tmp, ra);
+
+ emit_insn (gen_eh_return_1 (sa));
+ emit_barrier ();
+ DONE;
+ }")
+
+ (define_insn_and_split "eh_return_1"
+ [(unspec_volatile [(match_operand 0 "register_operand" "c")] 13)]
+ ""
+ "#"
+ "reload_completed"
+ [(const_int 1)]
+ "ix86_expand_epilogue (2); DONE;")
+
(define_insn "leave"
[(set (reg:SI 7) (reg:SI 6))
(set (reg:SI 6) (mem:SI (pre_dec:SI (reg:SI 7))))]
***************
*** 15751,15765 ****
operands[1])));
emit_move_insn (operands[0], virtual_stack_dynamic_rtx);
- DONE;
- }")
-
- (define_expand "exception_receiver"
- [(const_int 0)]
- "flag_pic"
- "
- {
- load_pic_register ();
DONE;
}")
--- 15781,15786 ----
Index: config/i386/linux.h
===================================================================
RCS file: /cvs/gcc/gcc/gcc/config/i386/linux.h,v
retrieving revision 1.24
diff -c -p -d -r1.24 linux.h
*** linux.h 2001/03/19 18:07:32 1.24
--- linux.h 2001/03/28 11:10:27
*************** Boston, MA 02111-1307, USA. */
*** 188,190 ****
--- 188,252 ----
} \
while (0)
#endif
+
+ /* Do code reading to identify a signal frame, and set the frame
+ state data appropriately. See unwind-dw2.c for the structs. */
+
+ #ifdef IN_LIBGCC2
+ #include <signal.h>
+ #include <sys/ucontext.h>
+ #endif
+
+ #define MD_FALLBACK_FRAME_STATE_FOR(CONTEXT, FS, SUCCESS) \
+ do { \
+ unsigned char *pc_ = (CONTEXT)->ra; \
+ struct sigcontext *sc_; \
+ long new_cfa_; \
+ \
+ /* popl %eax ; movl $__NR_sigreturn,%eax ; int $0x80 */ \
+ if (*(unsigned short *)(pc_+0) == 0xb858 \
+ && *(unsigned int *)(pc_+2) == 119 \
+ && *(unsigned short *)(pc_+6) == 0x80cd) \
+ sc_ = (CONTEXT)->cfa + 4; \
+ /* movl $__NR_rt_sigreturn,%eax ; int $0x80 */ \
+ else if (*(unsigned char *)(pc_+0) == 0xb8 \
+ && *(unsigned int *)(pc_+1) == 173 \
+ && *(unsigned short *)(pc_+5) == 0x80cd) \
+ { \
+ struct rt_sigframe { \
+ int sig; \
+ struct siginfo *pinfo; \
+ void *puc; \
+ struct siginfo info; \
+ struct ucontext uc; \
+ } *rt_ = (CONTEXT)->cfa; \
+ sc_ = (struct sigcontext *) &rt_->uc.uc_mcontext; \
+ } \
+ else \
+ break; \
+ \
+ new_cfa_ = sc_->esp; \
+ (FS)->cfa_how = CFA_REG_OFFSET; \
+ (FS)->cfa_reg = 4; \
+ (FS)->cfa_offset = new_cfa_ - (long) (CONTEXT)->cfa; \
+ \
+ /* The SVR4 register numbering macros aren't usable in libgcc. */ \
+ (FS)->regs.reg[0].how = REG_SAVED_OFFSET; \
+ (FS)->regs.reg[0].loc.offset = (long)&sc_->eax - new_cfa_; \
+ (FS)->regs.reg[3].how = REG_SAVED_OFFSET; \
+ (FS)->regs.reg[3].loc.offset = (long)&sc_->ebx - new_cfa_; \
+ (FS)->regs.reg[1].how = REG_SAVED_OFFSET; \
+ (FS)->regs.reg[1].loc.offset = (long)&sc_->ecx - new_cfa_; \
+ (FS)->regs.reg[2].how = REG_SAVED_OFFSET; \
+ (FS)->regs.reg[2].loc.offset = (long)&sc_->edx - new_cfa_; \
+ (FS)->regs.reg[6].how = REG_SAVED_OFFSET; \
+ (FS)->regs.reg[6].loc.offset = (long)&sc_->esi - new_cfa_; \
+ (FS)->regs.reg[7].how = REG_SAVED_OFFSET; \
+ (FS)->regs.reg[7].loc.offset = (long)&sc_->edi - new_cfa_; \
+ (FS)->regs.reg[5].how = REG_SAVED_OFFSET; \
+ (FS)->regs.reg[5].loc.offset = (long)&sc_->ebp - new_cfa_; \
+ (FS)->regs.reg[8].how = REG_SAVED_OFFSET; \
+ (FS)->regs.reg[8].loc.offset = (long)&sc_->eip - new_cfa_; \
+ (FS)->retaddr_column = 8; \
+ goto SUCCESS; \
+ } while (0)