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Re: [avr-libc-dev] [AVR] RTL prologue/epilogue
|
From: |
Anatoly Sokolov |
|
Subject: |
Re: [avr-libc-dev] [AVR] RTL prologue/epilogue |
|
Date: |
Tue, 18 Jul 2006 20:13:33 +0400 |
----- Original Message -----
From: "Denis Chertykov" <address@hidden>
To: "Anatoly Sokolov" <address@hidden>
Cc: <address@hidden>; <address@hidden>; "Denis Chertykov" <address@hidden>;
<address@hidden>
Sent: Monday, June 26, 2006 6:51 PM
Subject: Re: [avr-libc-dev] [AVR] RTL prologue/epilogue
>> >
>> > Attached is modifed Andy Hutchinson patch that changes AVR GCC to use RTL
>> > prologue/epilogue generation.
>> > Original patch: http://gcc.gnu.org/ml/gcc/2005-03/msg00923.html
>> >
>> > New pach is for GCC 4.2.
>
It is necessary to do:
> This patch seems wrong for me:
> 2. insn "incstackhi" (Now - "subhi3_sp_1", "subhi3_sp_2", ..., "subhi3_sp_6")
> must be part of addhi
> (even more I would to have addhi sp,
> -1 push
> -2 rcall
> -3 push + rcall
> -4 rcall + rcall
> -5 rcall + rcall + push
> -6 rcall + rcall + rcall);
> 5. ... "jump_exit" - ...., better to generate real jump insn and label 'exit'.
Anatoly.
Index: gcc/config/avr/avr-protos.h
===================================================================
--- gcc/config/avr/avr-protos.h (revision 115554)
+++ gcc/config/avr/avr-protos.h (working copy)
@@ -88,6 +88,10 @@
extern const char *lshrhi3_out (rtx insn, rtx operands[], int *len);
extern const char *lshrsi3_out (rtx insn, rtx operands[], int *len);
+extern void expand_prologue (void);
+extern void expand_epilogue (void);
+extern int avr_epilogue_uses (int regno);
+
extern void avr_output_bld (rtx operands[], int bit_nr);
extern void avr_output_addr_vec_elt (FILE *stream, int value);
extern const char *avr_out_sbxx_branch (rtx insn, rtx operands[]);
Index: gcc/config/avr/avr.md
===================================================================
--- gcc/config/avr/avr.md (revision 115554)
+++ gcc/config/avr/avr.md (working copy)
@@ -43,11 +43,24 @@
(REG_Y 28)
(REG_Z 30)
(REG_W 24)
+ (REG_SP 32)
(TMP_REGNO 0) ; temporary register r0
(ZERO_REGNO 1) ; zero register r1
+
+ (SREG_ADDR 0x5F)
+
(UNSPEC_STRLEN 0)
- (UNSPEC_INDEX_JMP 1)])
+ (UNSPEC_INDEX_JMP 1)
+ (UNSPEC_SEI 2)
+ (UNSPEC_CLI 3)
+ (UNSPEC_CLR_ZERO_REG 4)
+ (UNSPECV_RETI 5)
+ (UNSPECV_PROLOGUE_SAVES 6)
+ (UNSPECV_EPILOGUE_RESTORES 7)
+
+ (UNSPECV_JMP_EXIT 101)])
+
(include "constraints.md")
;; Condition code settings.
@@ -142,6 +155,48 @@
pop __tmp_reg__"
[(set_attr "length" "5")])
+(define_insn "*subhi3_sp_1"
+ [(set (reg:HI 32) (minus:HI (reg:HI 32) (const_int 1)))]
+ ""
+ "push __tmp_reg__"
+ [(set_attr "length" "1")])
+
+(define_insn "*subhi3_sp_2"
+ [(set (reg:HI 32) (minus:HI (reg:HI 32) (const_int 2)))]
+ "AVR_2_BYTE_PC"
+ "rcall ."
+ [(set_attr "length" "1")])
+
+(define_insn "*subhi3_sp_3"
+ [(set (reg:HI 32) (minus:HI (reg:HI 32) (const_int 3)))]
+ "AVR_2_BYTE_PC"
+ "rcall .
+ push __tmp_reg__"
+ [(set_attr "length" "2")])
+
+(define_insn "*subhi3_sp_4"
+ [(set (reg:HI 32) (minus:HI (reg:HI 32) (const_int 4)))]
+ "AVR_2_BYTE_PC"
+ "rcall .
+ rcall ."
+ [(set_attr "length" "2")])
+
+(define_insn "*subhi3_sp_5"
+ [(set (reg:HI 32) (minus:HI (reg:HI 32) (const_int 5)))]
+ "AVR_2_BYTE_PC"
+ "rcall .
+ rcall .
+ push __tmp_reg__"
+ [(set_attr "length" "3")])
+
+(define_insn "*subhi3_sp_6"
+ [(set (reg:HI 32) (minus:HI (reg:HI 32) (const_int 6)))]
+ "AVR_2_BYTE_PC"
+ "rcall .
+ rcall .
+ rcall ."
+ [(set_attr "length" "3")])
+
(define_insn "*pushqi"
[(set (mem:QI (post_dec (reg:HI 32)))
(match_operand:QI 0 "nonmemory_operand" "r,L"))]
@@ -179,7 +234,23 @@
push %B0
push %A0"
[(set_attr "length" "4")])
-
+
+(define_insn "popqi"
+ [(set (match_operand:QI 0 "register_operand" "=r")
+ (mem:QI (post_inc (reg:HI REG_SP))))]
+ ""
+ "pop %0"
+ [(set_attr "cc" "none")
+ (set_attr "length" "1")])
+
+(define_insn "pophi"
+ [(set (match_operand:HI 0 "register_operand" "=r")
+ (mem:HI (post_inc (reg:HI REG_SP))))]
+ ""
+ "pop %A0\;pop %B0"
+ [(set_attr "cc" "none")
+ (set_attr "length" "2")])
+
;;========================================================================
;; move byte
;; The last alternative (any immediate constant to any register) is
@@ -2536,3 +2607,136 @@
(pc)))]
"jump_over_one_insn_p (insn, operands[2])"
"cpse %0,%1")
+
+;;pppppppppppppppppppppppppppppppppppppppppppppppppppp
+;;prologue/epilogue support instructions
+
+;; Enable Interrupts
+(define_insn "enable_interrupt"
+ [(unspec [(const_int 0)] UNSPEC_SEI)]
+ ""
+ "sei"
+ [(set_attr "length" "1")
+ (set_attr "cc" "none")
+ ])
+
+;; Disable Interrupts
+(define_insn "disable_interrupt"
+ [(unspec [(const_int 0)] UNSPEC_CLI)]
+ ""
+ "cli"
+ [(set_attr "length" "1")
+ (set_attr "cc" "none")
+ ])
+
+;; Unspec to clr r1 or gcc will attempt to delete it.
+(define_insn "clr_zero_reg"
+ [(unspec [(const_int 0)] UNSPEC_CLR_ZERO_REG)
+ (set (reg:QI 1) (const_int 0))]
+ ""
+ "clr __zero_reg__"
+ [(set_attr "length" "1")
+ (set_attr "cc" "clobber")
+ ])
+
+; Library prologue saves
+(define_insn "call_prologue_saves"
+ [(unspec_volatile:HI [(const_int 0)] UNSPECV_PROLOGUE_SAVES)
+ (set (reg:HI 32 ) (minus:HI
+ (reg:HI 32)
+ (match_operand:HI 0 "immediate_operand" "")))
+ (set (reg:HI 32 ) (minus:HI
+ (reg:HI 32)
+ (match_operand:HI 1 "immediate_operand" "")))
+ (set (reg:HI 26) (match_dup 0))
+ (clobber (reg:HI 30))]
+ ""
+ "*
+ {
+ return (AS2 (ldi,r26,lo8(%0)) CR_TAB
+ AS2 (ldi,r27,hi8(%0)) CR_TAB
+ AS2 (ldi,r30,pm_lo8(1f)) CR_TAB
+ AS2 (ldi,r31,pm_hi8(1f)) CR_TAB
+ AS1 (%~jmp,__prologue_saves__+(%1)) \"\\n\"
+ \"1:\");
+ }"
+ [(set_attr_alternative "length"
+ [(if_then_else (eq_attr "mcu_mega" "yes")
+ (const_int 6)
+ (const_int 5))])
+ (set_attr "cc" "clobber")
+ ])
+
+; epilogue restores using library
+(define_insn "epilogue_restores"
+ [(unspec_volatile:QI [(const_int 0)] UNSPECV_EPILOGUE_RESTORES)
+ (set (reg:HI 28 ) (plus:HI
+ (reg:HI 28)
+ (match_operand:HI 0 "immediate_operand" "")))
+ (set (reg:HI 32) (reg:HI 28))
+ (clobber (reg:QI 30))]
+ ""
+ "*
+ {
+ rtx ops[4];
+ ops[0]=operands[0];
+ ops[1]=gen_int_mode((18 - INTVAL(operands[0])) * 2,HImode);
+
+ output_asm_insn(AS2 (ldi,r30,lo8(%0)),ops);
+ output_asm_insn(AS1 (%~jmp,__epilogue_restores__+(%1)),ops);
+
+ return \"\";
+ }"
+ [(set_attr_alternative "length"
+ [(if_then_else (eq_attr "mcu_mega" "yes")
+ (const_int 3)
+ (const_int 2))])
+ (set_attr "cc" "clobber")
+ ])
+
+; Main epilogue jump to exit
+(define_insn "jump_exit"
+ [(unspec_volatile:HI [(const_int 0)] UNSPECV_JMP_EXIT)]
+ ""
+ "%~jmp exit"
+ [(set_attr_alternative "length"
+ [(if_then_else (eq_attr "mcu_mega" "yes")
+ (const_int 2)
+ (const_int 1))])
+ (set_attr "cc" "clobber")
+ ])
+
+(define_insn "ret"
+ [(return)]
+ "reload_completed"
+ "ret"
+ [(set_attr "cc" "none")
+ (set_attr "length" "1")])
+
+(define_insn "reti"
+ [(unspec_volatile:QI [(const_int 0)] UNSPECV_RETI)
+ (return)]
+ "reload_completed"
+ "reti"
+ [(set_attr "cc" "none")
+ (set_attr "length" "1")])
+
+
+(define_expand "prologue"
+ [(const_int 0)]
+ ""
+ "
+ {
+ expand_prologue ();
+ DONE;
+ }")
+
+(define_expand "epilogue"
+ [(const_int 0)]
+ ""
+ "
+ {
+ expand_epilogue ();
+ DONE;
+ }")
+
\ No newline at end of file
Index: gcc/config/avr/avr.c
===================================================================
--- gcc/config/avr/avr.c (revision 115554)
+++ gcc/config/avr/avr.c (working copy)
@@ -56,8 +56,7 @@
static const char *ptrreg_to_str (int);
static const char *cond_string (enum rtx_code);
static int avr_num_arg_regs (enum machine_mode, tree);
-static int out_adj_frame_ptr (FILE *, int);
-static int out_set_stack_ptr (FILE *, int, int);
+
static RTX_CODE compare_condition (rtx insn);
static int compare_sign_p (rtx insn);
static tree avr_handle_progmem_attribute (tree *, tree, tree, int, bool *);
@@ -66,8 +65,8 @@
static bool avr_assemble_integer (rtx, unsigned int, int);
static void avr_file_start (void);
static void avr_file_end (void);
-static void avr_output_function_prologue (FILE *, HOST_WIDE_INT);
-static void avr_output_function_epilogue (FILE *, HOST_WIDE_INT);
+static void avr_asm_function_end_prologue (FILE *);
+static void avr_asm_function_begin_epilogue (FILE *);
static void avr_insert_attributes (tree, tree *);
static void avr_asm_init_sections (void);
static unsigned int avr_section_type_flags (tree, const char *, int);
@@ -79,7 +78,15 @@
static bool avr_rtx_costs (rtx, int, int, int *);
static int avr_address_cost (rtx);
static bool avr_return_in_memory (tree, tree);
+static bool is_prologue_epilogue_insn(rtx insn);
+/* A C structure for machine-specific, per-function data.
+ This is added to the cfun structure. */
+struct machine_function GTY(())
+{
+ int interrupt_handler;
+};
+
/* Allocate registers from r25 to r8 for parameters for function calls. */
#define FIRST_CUM_REG 26
@@ -107,9 +114,12 @@
/* Prologue/Epilogue size in words */
static int prologue_size;
static int epilogue_size;
+/* Flag is true if we are building prologue/epilogue */
+static bool building_prologue_epilogue;
/* Size of all jump tables in the current function, in words. */
static int jump_tables_size;
+static int function_size;
/* Preprocessor macros to define depending on MCU type. */
const char *avr_base_arch_macro;
@@ -276,10 +286,10 @@
#undef TARGET_ASM_FILE_END
#define TARGET_ASM_FILE_END avr_file_end
-#undef TARGET_ASM_FUNCTION_PROLOGUE
-#define TARGET_ASM_FUNCTION_PROLOGUE avr_output_function_prologue
-#undef TARGET_ASM_FUNCTION_EPILOGUE
-#define TARGET_ASM_FUNCTION_EPILOGUE avr_output_function_epilogue
+#undef TARGET_ASM_FUNCTION_END_PROLOGUE
+#define TARGET_ASM_FUNCTION_END_PROLOGUE avr_asm_function_end_prologue
+#undef TARGET_ASM_FUNCTION_BEGIN_EPILOGUE
+#define TARGET_ASM_FUNCTION_BEGIN_EPILOGUE avr_asm_function_begin_epilogue
#undef TARGET_ATTRIBUTE_TABLE
#define TARGET_ATTRIBUTE_TABLE avr_attribute_table
#undef TARGET_ASM_FUNCTION_RODATA_SECTION
@@ -303,6 +313,14 @@
struct gcc_target targetm = TARGET_INITIALIZER;
+
+static struct machine_function *
+avr_init_machine_status (void)
+{
+ return ((struct machine_function *)
+ ggc_alloc_cleared (sizeof (struct machine_function)));
+}
+
void
avr_override_options (void)
{
@@ -334,6 +352,8 @@
tmp_reg_rtx = gen_rtx_REG (QImode, TMP_REGNO);
zero_reg_rtx = gen_rtx_REG (QImode, ZERO_REGNO);
+
+ init_machine_status = avr_init_machine_status;
}
/* return register class from register number. */
@@ -526,254 +546,285 @@
}
-/* Output to FILE the asm instructions to adjust the frame pointer by
- ADJ (r29:r28 -= ADJ;) which can be positive (prologue) or negative
- (epilogue). Returns the number of instructions generated. */
-
-static int
-out_adj_frame_ptr (FILE *file, int adj)
+static int size_of_insn(rtx insn)
{
- int size = 0;
-
- if (adj)
- {
- if (TARGET_TINY_STACK)
- {
- if (adj < -63 || adj > 63)
- warning (0, "large frame pointer change (%d) with -mtiny-stack", adj);
-
- /* The high byte (r29) doesn't change - prefer "subi" (1 cycle)
- over "sbiw" (2 cycles, same size). */
-
- fprintf (file, (AS2 (subi, r28, %d) CR_TAB), adj);
- size++;
- }
- else if (adj < -63 || adj > 63)
- {
- fprintf (file, (AS2 (subi, r28, lo8(%d)) CR_TAB
- AS2 (sbci, r29, hi8(%d)) CR_TAB),
- adj, adj);
- size += 2;
- }
- else if (adj < 0)
- {
- fprintf (file, (AS2 (adiw, r28, %d) CR_TAB), -adj);
- size++;
- }
- else
- {
- fprintf (file, (AS2 (sbiw, r28, %d) CR_TAB), adj);
- size++;
- }
- }
- return size;
+ int l=get_attr_length (insn);
+ l= adjust_insn_length (insn,l);
+ return l;
}
-
-/* Output to FILE the asm instructions to copy r29:r28 to SPH:SPL,
- handling various cases of interrupt enable flag state BEFORE and AFTER
- (0=disabled, 1=enabled, -1=unknown/unchanged) and target_flags.
- Returns the number of instructions generated. */
-
-static int
-out_set_stack_ptr (FILE *file, int before, int after)
+/* Return true if insn is part of prologue or epilogue.*/
+static bool is_prologue_epilogue_insn(rtx insn)
{
- int do_sph, do_cli, do_save, do_sei, lock_sph, size;
-
- /* The logic here is so that -mno-interrupts actually means
- "it is safe to write SPH in one instruction, then SPL in the
- next instruction, without disabling interrupts first".
- The after != -1 case (interrupt/signal) is not affected. */
-
- do_sph = !TARGET_TINY_STACK;
- lock_sph = do_sph && !TARGET_NO_INTERRUPTS;
- do_cli = (before != 0 && (after == 0 || lock_sph));
- do_save = (do_cli && before == -1 && after == -1);
- do_sei = ((do_cli || before != 1) && after == 1);
- size = 1;
-
- if (do_save)
- {
- fprintf (file, AS2 (in, __tmp_reg__, __SREG__) CR_TAB);
- size++;
- }
-
- if (do_cli)
- {
- fprintf (file, "cli" CR_TAB);
- size++;
- }
-
- /* Do SPH first - maybe this will disable interrupts for one instruction
- someday (a suggestion has been sent to address@hidden for consideration
- in future devices - that would make -mno-interrupts always safe). */
- if (do_sph)
- {
- fprintf (file, AS2 (out, __SP_H__, r29) CR_TAB);
- size++;
- }
-
- /* Set/restore the I flag now - interrupts will be really enabled only
- after the next instruction. This is not clearly documented, but
- believed to be true for all AVR devices. */
- if (do_save)
- {
- fprintf (file, AS2 (out, __SREG__, __tmp_reg__) CR_TAB);
- size++;
- }
- else if (do_sei)
- {
- fprintf (file, "sei" CR_TAB);
- size++;
- }
-
- fprintf (file, AS2 (out, __SP_L__, r28) "\n");
-
- return size;
+ return (building_prologue_epilogue || prologue_epilogue_contains(insn));
}
-
-
-/* Output function prologue. */
-
-static void
-avr_output_function_prologue (FILE *file, HOST_WIDE_INT size)
+/* Placeholders for prologue saving of tmp/zero regs in ISR. */
+/* Unused - potential future enhancement to avoid save/restores. */
+static int uses_zero_reg =true;
+static int uses_tmp_reg = true;
+static int uses_status_reg = true;
+/* Output function prologue. */
+void
+expand_prologue (void)
{
- int reg;
int interrupt_func_p;
int signal_func_p;
int main_p;
int live_seq;
int minimize;
-
+ HOST_WIDE_INT size =get_frame_size();
+ building_prologue_epilogue=true;
last_insn_address = 0;
jump_tables_size = 0;
prologue_size = 0;
- fprintf (file, "/* prologue: frame size=" HOST_WIDE_INT_PRINT_DEC " */\n",
- size);
-
+ /* Define templates for push instructions. */
+ rtx pushbyte = gen_rtx_MEM (QImode,
+ gen_rtx_POST_DEC (HImode, stack_pointer_rtx));
+ rtx pushword = gen_rtx_MEM (HImode,
+ gen_rtx_POST_DEC (HImode, stack_pointer_rtx));
+ rtx insn;
+
if (avr_naked_function_p (current_function_decl))
{
- fputs ("/* prologue: naked */\n", file);
+ /* prologue: naked */
goto out;
}
-
interrupt_func_p = interrupt_function_p (current_function_decl);
signal_func_p = signal_function_p (current_function_decl);
main_p = MAIN_NAME_P (DECL_NAME (current_function_decl));
live_seq = sequent_regs_live ();
minimize = (TARGET_CALL_PROLOGUES
&& !interrupt_func_p && !signal_func_p && live_seq);
+ cfun->machine->interrupt_handler = (interrupt_func_p || signal_func_p);
- if (interrupt_func_p)
- {
- fprintf (file,"\tsei\n");
- ++prologue_size;
- }
if (interrupt_func_p || signal_func_p)
{
- fprintf (file, "\t"
- AS1 (push,__zero_reg__) CR_TAB
- AS1 (push,__tmp_reg__) CR_TAB
- AS2 (in,__tmp_reg__,__SREG__) CR_TAB
- AS1 (push,__tmp_reg__) CR_TAB
- AS1 (clr,__zero_reg__) "\n");
- prologue_size += 5;
+ if (interrupt_func_p)
+ {
+ /* enable interrupts */
+ insn = emit_insn (gen_enable_interrupt ());
+ RTX_FRAME_RELATED_P (insn) = 1;
+ prologue_size +=size_of_insn (insn);
+ }
+ /* Push tmp, zero regs and SREG status. */
+ if (uses_tmp_reg)
+ {
+ insn = emit_move_insn (pushbyte,tmp_reg_rtx);
+ RTX_FRAME_RELATED_P (insn) = 1;
+ prologue_size += size_of_insn (insn);
+ }
+ if (uses_status_reg)
+ {
+ /* push SREG */
+ insn = emit_move_insn (tmp_reg_rtx,
+ gen_rtx_MEM(QImode, GEN_INT(SREG_ADDR)));
+ RTX_FRAME_RELATED_P (insn) = 1;
+ prologue_size += size_of_insn (insn);
+ insn=emit_move_insn (pushbyte, tmp_reg_rtx);
+ RTX_FRAME_RELATED_P (insn) = 1;
+ prologue_size += size_of_insn (insn);
+ }
+ if (uses_zero_reg)
+ {
+ insn = emit_move_insn (pushbyte,zero_reg_rtx);
+ RTX_FRAME_RELATED_P (insn) = 1;
+ prologue_size += size_of_insn (insn);
+
+ /* Clear zero reg, Use unspec so gcc wont try to remove it. */
+ //insn = emit_move_insn (zero_reg_rtx, const0_rtx);
+ //REG_NOTES (insn) = gen_rtx_EXPR_LIST (REG_MAYBE_DEAD, const0_rtx,
NULL);
+ insn = emit_insn (gen_clr_zero_reg ());
+ RTX_FRAME_RELATED_P (insn) = 1;
+ prologue_size += size_of_insn (insn);
+ }
}
if (main_p)
{
- fprintf (file, ("\t"
- AS1 (ldi,r28) ",lo8(%s - " HOST_WIDE_INT_PRINT_DEC ")" CR_TAB
- AS1 (ldi,r29) ",hi8(%s - " HOST_WIDE_INT_PRINT_DEC ")" CR_TAB
- AS2 (out,__SP_H__,r29) CR_TAB
- AS2 (out,__SP_L__,r28) "\n"),
- avr_init_stack, size, avr_init_stack, size);
-
- prologue_size += 4;
+ char buffer[40];
+ sprintf (buffer,"%s - %d", avr_init_stack,(int) size);
+ rtx sym = gen_rtx_SYMBOL_REF (HImode, ggc_strdup (buffer));
+ /* Initialise stack pointer using frame pointer */
+ insn = emit_move_insn (frame_pointer_rtx, sym);
+ RTX_FRAME_RELATED_P (insn) = 1;
+ prologue_size += size_of_insn (insn);
+ insn=emit_move_insn (stack_pointer_rtx, frame_pointer_rtx);
+ RTX_FRAME_RELATED_P (insn) = 1;
+ prologue_size += size_of_insn (insn);
}
else if (minimize && (frame_pointer_needed || live_seq > 6))
{
- fprintf (file, ("\t"
- AS1 (ldi, r26) ",lo8(" HOST_WIDE_INT_PRINT_DEC ")" CR_TAB
- AS1 (ldi, r27) ",hi8(" HOST_WIDE_INT_PRINT_DEC ")" CR_TAB), size,
size);
-
- fputs ((AS2 (ldi,r30,pm_lo8(1f)) CR_TAB
- AS2 (ldi,r31,pm_hi8(1f)) CR_TAB), file);
-
- prologue_size += 4;
-
- if (AVR_MEGA)
- {
- fprintf (file, AS1 (jmp,__prologue_saves__+%d) "\n",
- (18 - live_seq) * 2);
- prologue_size += 2;
- }
- else
- {
- fprintf (file, AS1 (rjmp,__prologue_saves__+%d) "\n",
- (18 - live_seq) * 2);
- ++prologue_size;
- }
- fputs ("1:\n", file);
+ insn = emit_insn (gen_call_prologue_saves(
+ gen_int_mode (size, HImode),
+ gen_int_mode ((18 - live_seq) * 2, HImode)));
+ RTX_FRAME_RELATED_P (insn) = 1;
+ prologue_size += size_of_insn (insn);
+ /* Label for body */
+ rtx label = gen_label_rtx ();
+ emit_label (label);
}
else
{
HARD_REG_SET set;
-
- prologue_size += avr_regs_to_save (&set);
+ avr_regs_to_save (&set);
+ int reg;
for (reg = 0; reg < 32; ++reg)
- {
- if (TEST_HARD_REG_BIT (set, reg))
- {
- fprintf (file, "\t" AS1 (push,%s) "\n", avr_regnames[reg]);
- }
- }
+ {
+ if (TEST_HARD_REG_BIT (set, reg))
+ {
+ /* Emit push of register to save. */
+ insn=emit_move_insn (pushbyte, gen_rtx_REG (QImode, reg));
+ RTX_FRAME_RELATED_P (insn) = 1;
+ prologue_size +=size_of_insn (insn);
+ }
+ }
if (frame_pointer_needed)
- {
- fprintf (file, "\t"
- AS1 (push,r28) CR_TAB
- AS1 (push,r29) CR_TAB
- AS2 (in,r28,__SP_L__) CR_TAB
- AS2 (in,r29,__SP_H__) "\n");
- prologue_size += 4;
- if (size)
- {
- fputs ("\t", file);
- prologue_size += out_adj_frame_ptr (file, size);
+ {
+ /* Push frame pointer. */
+ insn = emit_move_insn (pushword, frame_pointer_rtx);
+ RTX_FRAME_RELATED_P (insn) = 1;
+ prologue_size += size_of_insn (insn);
+ if (!size)
+ {
+ insn = emit_move_insn (frame_pointer_rtx, stack_pointer_rtx);
+ RTX_FRAME_RELATED_P (insn) = 1;
+ prologue_size += size_of_insn (insn);
+ }
+ else
+ {
+ /* Creating a frame can be done by direct manipulation of the
+ stack or via the frame pointer. These two methods are:
+ fp=sp
+ fp-=size
+ sp=fp
+ OR
+ sp-=size
+ fp=sp
+ the optimum method depends on function type, stack and frame
size.
+ To avoid a complex logic, both methods are tested and shortest
+ is selected */
+ rtx myfp;
+ /* First method. */
+ if (TARGET_TINY_STACK)
+ {
+ if (size < -63 || size > 63)
+ warning ("large frame pointer change (%d) with
-mtiny-stack", size);
+
+ /* The high byte (r29) doesn't change - prefer 'subi' (1
cycle)
+ over 'sbiw' (2 cycles, same size). */
+ myfp = gen_rtx_REG (QImode,REGNO (frame_pointer_rtx));
+ }
+ else
+ {
+ /* Normal sized addition. */
+ myfp=frame_pointer_rtx;
+ }
+ /* calculate length */
+ int method1_length;
+ method1_length = size_of_insn (gen_move_insn (
+ frame_pointer_rtx, stack_pointer_rtx));
+ method1_length += size_of_insn (gen_move_insn (myfp,
+ gen_rtx_PLUS (GET_MODE(myfp), myfp,
+ gen_int_mode (-size,GET_MODE(myfp)))));
+ /* output_movhi() takes care of variants*/
+ method1_length += size_of_insn(gen_move_insn (
+ stack_pointer_rtx, frame_pointer_rtx));
+
+ /* Method 2-Adjust Stack pointer. */
+ int sp_plus_length = 0;
+ if (size <= 6)
+ {
+ sp_plus_length = size_of_insn (gen_move_insn (
+ stack_pointer_rtx,
+ gen_rtx_MINUS (HImode, stack_pointer_rtx,
+ gen_int_mode (size, HImode))));
+ sp_plus_length += size_of_insn (gen_move_insn (
+ frame_pointer_rtx, stack_pointer_rtx));
+ }
+ /* Use shortest method. */
+ if (size <= 6 && (sp_plus_length<method1_length))
+ {
+ insn = emit_move_insn (stack_pointer_rtx,
+ gen_rtx_MINUS (HImode, stack_pointer_rtx,
+ gen_int_mode (size, HImode)));
+ RTX_FRAME_RELATED_P (insn) = 1;
+ insn = emit_move_insn (frame_pointer_rtx, stack_pointer_rtx);
+ RTX_FRAME_RELATED_P (insn) = 1;
+ prologue_size += sp_plus_length;
+ }
+ else
+ {
+ insn = emit_move_insn (frame_pointer_rtx, stack_pointer_rtx);
+ RTX_FRAME_RELATED_P (insn) = 1;
+ insn = emit_move_insn (myfp,
+ gen_rtx_PLUS (GET_MODE(myfp), frame_pointer_rtx,
+ gen_int_mode (-size,GET_MODE(myfp))));
+ RTX_FRAME_RELATED_P (insn) = 1;
+ insn = emit_move_insn ( stack_pointer_rtx,frame_pointer_rtx);
+ RTX_FRAME_RELATED_P (insn) = 1;
+ prologue_size += method1_length;
+ }
+ }
+ }
+ }
+ out:
+ building_prologue_epilogue=false;
+}
- if (interrupt_func_p)
- {
- prologue_size += out_set_stack_ptr (file, 1, 1);
- }
- else if (signal_func_p)
- {
- prologue_size += out_set_stack_ptr (file, 0, 0);
- }
- else
- {
- prologue_size += out_set_stack_ptr (file, -1, -1);
- }
- }
- }
+/* Output summary at end of function prologue. */
+static void
+avr_asm_function_end_prologue (FILE *file)
+{
+ if (avr_naked_function_p (current_function_decl))
+ {
+ fputs ("/* prologue: naked */\n", file);
}
+ else
+ {
+ if (interrupt_function_p (current_function_decl))
+ {
+ fputs ("/* prologue: Interrupt */\n", file);
+ }
+ else if (signal_function_p (current_function_decl))
+ {
+ fputs ("/* prologue: Signal */\n", file);
+ }
+ else if (MAIN_NAME_P (DECL_NAME (current_function_decl)))
+ {
+ fputs ("/* prologue: main */\n", file);
+ }
+ else
+ fputs ("/* prologue: function */\n", file);
+ }
+ fprintf (file, "/* frame size=" HOST_WIDE_INT_PRINT_DEC
+ " prologue size %d */\n",
+ get_frame_size(), prologue_size);
+}
- out:
- fprintf (file, "/* prologue end (size=%d) */\n", prologue_size);
+
+/* Implement EPILOGUE_USES. */
+int
+avr_epilogue_uses (int regno)
+{
+ if (cfun->machine && cfun->machine->interrupt_handler && reload_completed)
+ return 1;
+ return 0;
}
-/* Output function epilogue. */
+/* Output RTL epilogue. */
-static void
-avr_output_function_epilogue (FILE *file, HOST_WIDE_INT size)
+void
+expand_epilogue (void)
{
int reg;
int interrupt_func_p;
int signal_func_p;
int main_p;
- int function_size;
int live_seq;
int minimize;
rtx last = get_last_nonnote_insn ();
-
+ HOST_WIDE_INT size = get_frame_size();
+ building_prologue_epilogue=true;
+ rtx insn;
function_size = jump_tables_size;
if (last)
{
@@ -782,19 +833,18 @@
INSN_ADDRESSES (INSN_UID (first)));
function_size += get_attr_length (last);
}
-
- fprintf (file, "/* epilogue: frame size=" HOST_WIDE_INT_PRINT_DEC " */\n",
size);
+
epilogue_size = 0;
if (avr_naked_function_p (current_function_decl))
{
- fputs ("/* epilogue: naked */\n", file);
+ /* epilogue: naked */
goto out;
}
if (last && GET_CODE (last) == BARRIER)
{
- fputs ("/* epilogue: noreturn */\n", file);
+ /* epilogue: noreturn */
goto out;
}
@@ -808,106 +858,159 @@
if (main_p)
{
/* Return value from main() is already in the correct registers
- (r25:r24) as the exit() argument. */
- if (AVR_MEGA)
- {
- fputs ("\t" AS1 (jmp,exit) "\n", file);
- epilogue_size += 2;
- }
- else
- {
- fputs ("\t" AS1 (rjmp,exit) "\n", file);
- ++epilogue_size;
- }
+ (r25:r24) as the exit() argument. */
+ insn = emit_insn (gen_jump_exit ());
+ RTX_FRAME_RELATED_P (insn) = 1;
+ epilogue_size += size_of_insn (insn);
}
else if (minimize && (frame_pointer_needed || live_seq > 4))
{
- fprintf (file, ("\t" AS2 (ldi, r30, %d) CR_TAB), live_seq);
- ++epilogue_size;
if (frame_pointer_needed)
{
- epilogue_size += out_adj_frame_ptr (file, -size);
+ /* Get rid of frame. */
+ insn = emit_move_insn(frame_pointer_rtx,
+ gen_rtx_PLUS (HImode, frame_pointer_rtx,
+ gen_int_mode (size, HImode)));
+ RTX_FRAME_RELATED_P (insn) = 1;
+ epilogue_size += size_of_insn (insn);
}
else
{
- fprintf (file, (AS2 (in , r28, __SP_L__) CR_TAB
- AS2 (in , r29, __SP_H__) CR_TAB));
- epilogue_size += 2;
+ insn = emit_move_insn (frame_pointer_rtx, stack_pointer_rtx);
+ RTX_FRAME_RELATED_P (insn) = 1;
+ epilogue_size += size_of_insn (insn);
}
-
- if (AVR_MEGA)
- {
- fprintf (file, AS1 (jmp,__epilogue_restores__+%d) "\n",
- (18 - live_seq) * 2);
- epilogue_size += 2;
- }
- else
- {
- fprintf (file, AS1 (rjmp,__epilogue_restores__+%d) "\n",
- (18 - live_seq) * 2);
- ++epilogue_size;
- }
+ insn = emit_insn (gen_epilogue_restores(
+ gen_int_mode (live_seq, HImode)));
+ RTX_FRAME_RELATED_P (insn) = 1;
+ epilogue_size+=size_of_insn (insn);
}
else
{
- HARD_REG_SET set;
-
if (frame_pointer_needed)
{
if (size)
{
- fputs ("\t", file);
- epilogue_size += out_adj_frame_ptr (file, -size);
-
- if (interrupt_func_p || signal_func_p)
- {
- epilogue_size += out_set_stack_ptr (file, -1, 0);
- }
- else
- {
- epilogue_size += out_set_stack_ptr (file, -1, -1);
- }
- }
- fprintf (file, "\t"
- AS1 (pop,r29) CR_TAB
- AS1 (pop,r28) "\n");
- epilogue_size += 2;
+ /* Try two methods to adjust stack and select shortest. */
+ int fp_plus_length;
+ /* Method 1-Adjust frame pointer. */
+ fp_plus_length =size_of_insn (gen_move_insn (
+ frame_pointer_rtx,
+ gen_rtx_PLUS (HImode,
frame_pointer_rtx,
+ gen_int_mode (size, HImode))));
+ /* Copy to stack pointer */
+ fp_plus_length += size_of_insn (gen_move_insn (
+ stack_pointer_rtx,
frame_pointer_rtx));
+
+ /* Method 2-Adjust Stack pointer. */
+ int sp_plus_length = 0;
+ if (size <= 5)
+ {
+ sp_plus_length = size_of_insn (gen_move_insn (
+ stack_pointer_rtx,
+ gen_rtx_PLUS (HImode,
stack_pointer_rtx,
+ gen_int_mode (size,
HImode))));
+ }
+ /* Use shortest method. */
+ if (size <= 5 && (sp_plus_length<fp_plus_length))
+ {
+ insn = emit_move_insn (stack_pointer_rtx,
+ gen_rtx_PLUS (HImode, stack_pointer_rtx,
+ gen_int_mode (size, HImode)));
+ RTX_FRAME_RELATED_P (insn) = 1;
+ epilogue_size += sp_plus_length;
+ }
+ else
+ {
+ insn = emit_move_insn (frame_pointer_rtx,
+ gen_rtx_PLUS (HImode,
frame_pointer_rtx,
+ gen_int_mode (size, HImode)));
+ RTX_FRAME_RELATED_P (insn) = 1;
+ /* Copy to stack pointer */
+ insn = emit_move_insn (stack_pointer_rtx,
frame_pointer_rtx);
+ RTX_FRAME_RELATED_P (insn) = 1;
+ epilogue_size += fp_plus_length;
+ }
+ }
+
+ /* Restore previous frame_pointer. */
+ insn = emit_insn (gen_pophi (frame_pointer_rtx));
+ RTX_FRAME_RELATED_P (insn) = 1;
+ epilogue_size += size_of_insn (insn);
}
-
- epilogue_size += avr_regs_to_save (&set);
+ /* Restore used registers. */
+ HARD_REG_SET set;
+ avr_regs_to_save (&set);
for (reg = 31; reg >= 0; --reg)
- {
- if (TEST_HARD_REG_BIT (set, reg))
- {
- fprintf (file, "\t" AS1 (pop,%s) "\n", avr_regnames[reg]);
- }
- }
-
+ {
+ if (TEST_HARD_REG_BIT (set, reg))
+ {
+ insn = emit_insn (gen_popqi (gen_rtx_REG (QImode, reg)));
+ RTX_FRAME_RELATED_P (insn) = 1;
+ epilogue_size += size_of_insn (insn);
+ }
+ }
if (interrupt_func_p || signal_func_p)
- {
- fprintf (file, "\t"
- AS1 (pop,__tmp_reg__) CR_TAB
- AS2 (out,__SREG__,__tmp_reg__) CR_TAB
- AS1 (pop,__tmp_reg__) CR_TAB
- AS1 (pop,__zero_reg__) "\n");
- epilogue_size += 4;
- fprintf (file, "\treti\n");
- }
+ {
+ if (uses_zero_reg)
+ {
+ insn = emit_insn (gen_popqi (zero_reg_rtx));
+ RTX_FRAME_RELATED_P (insn) = 1;
+ epilogue_size += size_of_insn (insn);
+ }
+ if (uses_status_reg)
+ {
+ /* Restore SREG using tmp reg as scratch. */
+ insn = emit_insn (gen_popqi (tmp_reg_rtx));
+ RTX_FRAME_RELATED_P (insn) = 1;
+ epilogue_size += size_of_insn (insn);
+
+ insn = emit_move_insn (gen_rtx_MEM(QImode, GEN_INT(SREG_ADDR)),
+ tmp_reg_rtx);
+ RTX_FRAME_RELATED_P (insn) = 1;
+ epilogue_size += size_of_insn (insn);
+ }
+ if (uses_tmp_reg)
+ {
+ insn = emit_insn (gen_popqi (tmp_reg_rtx));
+ RTX_FRAME_RELATED_P (insn) = 1;
+ epilogue_size += size_of_insn (insn);
+ }
+ insn = emit_insn (gen_reti ());
+ RTX_FRAME_RELATED_P (insn) = 1;
+ epilogue_size += size_of_insn (insn);
+ }
else
- fprintf (file, "\tret\n");
- ++epilogue_size;
+ {
+ insn = emit_insn (gen_ret ());
+ RTX_FRAME_RELATED_P (insn) = 1;
+ epilogue_size += size_of_insn (insn);
+ }
}
out:
- fprintf (file, "/* epilogue end (size=%d) */\n", epilogue_size);
- fprintf (file, "/* function %s size %d (%d) */\n", current_function_name (),
- prologue_size + function_size + epilogue_size, function_size);
commands_in_file += prologue_size + function_size + epilogue_size;
commands_in_prologues += prologue_size;
commands_in_epilogues += epilogue_size;
+ building_prologue_epilogue=false;
}
+/* Output summary messages at beginning of function epilogue. */
+static void
+avr_asm_function_begin_epilogue (FILE *file)
+{
+ fprintf (file, "/* function %s size %d (%d) */\n", current_function_name (),
+ prologue_size + function_size + epilogue_size, function_size);
+ fprintf (file, "/* epilogue start (size=%d) */\n", epilogue_size);
+ rtx last = get_last_nonnote_insn ();
+ if (last && GET_CODE (last) == BARRIER)
+ {
+ fputs ("/* epilogue: noreturn */\n", file);
+ }
+}
+
+
/* Return nonzero if X (an RTX) is a legitimate memory address on the target
machine for a memory operand of mode MODE. */
@@ -1642,13 +1745,32 @@
*l = 1;
return AS2 (out,__SP_L__,%A1);
}
- else if (TARGET_NO_INTERRUPTS)
- {
- *l = 2;
- return (AS2 (out,__SP_H__,%B1) CR_TAB
- AS2 (out,__SP_L__,%A1));
- }
-
+ /* Use simple load of stack pointer if no interrupts are used
+ or inside main or signal function prologue where they disabled*/
+ else if (TARGET_NO_INTERRUPTS
+ || (reload_completed
+ && MAIN_NAME_P (DECL_NAME (current_function_decl))
+ && is_prologue_epilogue_insn (insn))
+ || (reload_completed
+ && signal_function_p (current_function_decl)
+ && is_prologue_epilogue_insn (insn))
+ )
+ {
+ *l = 2;
+ return (AS2 (out,__SP_H__,%B1) CR_TAB
+ AS2 (out,__SP_L__,%A1));
+ }
+ /* In interrupt prolog we know interrupts are enabled. */
+ else if (reload_completed
+ && interrupt_function_p (current_function_decl)
+ && is_prologue_epilogue_insn (insn))
+ {
+ *l = 4;
+ return ("cli" CR_TAB
+ AS2 (out,__SP_H__,%B1) CR_TAB
+ "sei" CR_TAB
+ AS2 (out,__SP_L__,%A1));
+ }
*l = 5;
return (AS2 (in,__tmp_reg__,__SREG__) CR_TAB
"cli" CR_TAB
@@ -1796,6 +1918,11 @@
if (CONSTANT_ADDRESS_P (x))
{
+ if (GET_CODE (x) == CONST_INT && INTVAL (x) == SREG_ADDR)
+ {
+ *l = 1;
+ return AS2 (in,%0,__SREG__);
+ }
if (avr_io_address_p (x, 1))
{
*l = 1;
@@ -2479,6 +2606,11 @@
if (CONSTANT_ADDRESS_P (x))
{
+ if (GET_CODE (x) == CONST_INT && INTVAL (x) == SREG_ADDR)
+ {
+ *l = 1;
+ return AS2 (out,__SREG__,%1);
+ }
if (avr_io_address_p (x, 1))
{
*l = 1;
Index: gcc/config/avr/avr.h
===================================================================
--- gcc/config/avr/avr.h (revision 115554)
+++ gcc/config/avr/avr.h (working copy)
@@ -21,6 +21,9 @@
the Free Software Foundation, 51 Franklin Street, Fifth Floor,
Boston, MA 02110-1301, USA. */
+/* Offset from the frame pointer register value to the top of the stack. */
+#define FRAME_POINTER_CFA_OFFSET(FNDECL) 0
+
/* Names to predefine in the preprocessor for this target machine. */
#define TARGET_CPU_CPP_BUILTINS() \
@@ -60,6 +63,8 @@
#define AVR_ENHANCED (avr_enhanced_p)
#define AVR_HAVE_MOVW (avr_have_movw_lpmx_p)
+#define AVR_2_BYTE_PC 1
+
#define TARGET_VERSION fprintf (stderr, " (GNU assembler syntax)");
#define OVERRIDE_OPTIONS avr_override_options ()
@@ -332,7 +337,8 @@
#define DEFAULT_PCC_STRUCT_RETURN 0
-#define EPILOGUE_USES(REGNO) 0
+#define EPILOGUE_USES(REGNO) avr_epilogue_uses(REGNO)
+//&& reload_completed)
#define HAVE_POST_INCREMENT 1
#define HAVE_PRE_DECREMENT 1
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- Re: [avr-libc-dev] [AVR] RTL prologue/epilogue,
Anatoly Sokolov <=