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Commit 0903fcab by Jan Hubicka Committed by Jan Hubicka
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i386-protos.h (ix86_compute_frame_size): Remove prototype. 

	* i386-protos.h (ix86_compute_frame_size): Remove prototype.
	(ix86_initial_elimination_offset): Declare.
	* i386.c (ix86_nsaved_regs): Break out from ...
	(ix86_can_use_return_insn_p): ... here.
	(ix86_emit_save_regs): Break out from ...
	(ix86_expand_prologue): ... here.
	(ix86_emit_epilogue_esp_adjustment, ix86_emit_restore_regs): Break
	out from ...
	(ix86_expand_epilogue): ... here.
	(ix86_compute_frame_size): Make static, add prototype.
	(ix86_initial_elimination_offset): Break out from ...
	* i386.h (INITIAL_ELIMINATION_OFFSET): ... here.

From-SVN: r31529
parent e7746130
Showing with 173 additions and 100 deletions
gcc/ChangeLog
Thu Jan 20 01:01:23 MET 2000 Jan Hubicka <jh@suse.cz>
* i386-protos.h (ix86_compute_frame_size): Remove prototype.
(ix86_initial_elimination_offset): Declare.
* i386.c (ix86_nsaved_regs): Break out from ...
(ix86_can_use_return_insn_p): ... here.
(ix86_emit_save_regs): Break out from ...
(ix86_expand_prologue): ... here.
(ix86_emit_epilogue_esp_adjustment, ix86_emit_restore_regs): Break
out from ...
(ix86_expand_epilogue): ... here.
(ix86_compute_frame_size): Make static, add prototype.
(ix86_initial_elimination_offset): Break out from ...
* i386.h (INITIAL_ELIMINATION_OFFSET): ... here.
2000-01-19 Kaveh R. Ghazi <ghazi@caip.rutgers.edu>
* recog.h (OUT_FCN): Delete.
......
gcc/config/i386/i386-protos.h
......@@ -27,7 +27,7 @@ extern int ix86_can_use_return_insn_p PARAMS ((void));
extern void asm_output_function_prefix PARAMS ((FILE *, char *));
extern void load_pic_register PARAMS ((void));
extern HOST_WIDE_INT ix86_compute_frame_size PARAMS ((HOST_WIDE_INT, int *));
extern HOST_WIDE_INT ix86_initial_elimination_offset PARAMS((int, int));
extern void ix86_expand_prologue PARAMS ((void));
extern void ix86_expand_epilogue PARAMS ((void));
......
gcc/config/i386/i386.c
......@@ -325,6 +325,11 @@ static void ix86_init_machine_status PARAMS ((struct function *));
static void ix86_mark_machine_status PARAMS ((struct function *));
static void ix86_split_to_parts PARAMS ((rtx, rtx *, enum machine_mode));
static int ix86_safe_length_prefix PARAMS ((rtx));
static HOST_WIDE_INT ix86_compute_frame_size PARAMS((HOST_WIDE_INT, int *));
static int ix86_nsaved_regs PARAMS((void));
static void ix86_emit_save_regs PARAMS((void));
static void ix86_emit_restore_regs PARAMS((void));
static void ix86_emit_epilogue_esp_adjustment PARAMS((int));
struct ix86_address
{
......@@ -1434,13 +1439,6 @@ symbolic_reference_mentioned_p (op)
int
ix86_can_use_return_insn_p ()
{
int regno;
int nregs = 0;
int reglimit = (frame_pointer_needed
? FRAME_POINTER_REGNUM : STACK_POINTER_REGNUM);
int pic_reg_used = flag_pic && (current_function_uses_pic_offset_table
|| current_function_uses_const_pool);
#ifdef NON_SAVING_SETJMP
if (NON_SAVING_SETJMP && current_function_calls_setjmp)
return 0;
......@@ -1449,12 +1447,7 @@ ix86_can_use_return_insn_p ()
if (! reload_completed)
return 0;
for (regno = reglimit - 1; regno >= 0; regno--)
if ((regs_ever_live[regno] && ! call_used_regs[regno])
|| (regno == PIC_OFFSET_TABLE_REGNUM && pic_reg_used))
nregs++;
return nregs == 0 || ! frame_pointer_needed;
return ix86_nsaved_regs () == 0 || ! frame_pointer_needed;
}
static char *pic_label_name;
......@@ -1547,6 +1540,61 @@ gen_push (arg)
arg);
}
/* Return number of registers to be saved on the stack. */
static int
ix86_nsaved_regs ()
{
int nregs = 0;
int pic_reg_used = flag_pic && (current_function_uses_pic_offset_table
|| current_function_uses_const_pool);
int limit = (frame_pointer_needed
? HARD_FRAME_POINTER_REGNUM : STACK_POINTER_REGNUM);
int regno;
for (regno = limit - 1; regno >= 0; regno--)
if ((regs_ever_live[regno] && ! call_used_regs[regno])
|| (regno == PIC_OFFSET_TABLE_REGNUM && pic_reg_used))
{
nregs ++;
}
return nregs;
}
/* Return the offset between two registers, one to be eliminated, and the other
its replacement, at the start of a routine. */
HOST_WIDE_INT
ix86_initial_elimination_offset (from, to)
int from;
int to;
{
if (from == ARG_POINTER_REGNUM && to == FRAME_POINTER_REGNUM)
return 8; /* Skip saved PC and previous frame pointer */
else
{
int nregs;
int poffset;
int offset;
int preferred_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
HOST_WIDE_INT tsize = ix86_compute_frame_size (get_frame_size (),
&nregs);
offset = (tsize + nregs * UNITS_PER_WORD);
poffset = 4;
if (frame_pointer_needed)
poffset += UNITS_PER_WORD;
if (from == ARG_POINTER_REGNUM)
offset += poffset;
else
offset -= ((poffset + preferred_alignment - 1)
& -preferred_alignment) - poffset;
return offset;
}
}
/* Compute the size of local storage taking into consideration the
desired stack alignment which is to be maintained. Also determine
the number of registers saved below the local storage. */
......@@ -1608,13 +1656,33 @@ ix86_compute_frame_size (size, nregs_on_stack)
return size + padding;
}
/* Emit code to save registers in the prologue. */
static void
ix86_emit_save_regs ()
{
register int regno;
int limit;
rtx insn;
int pic_reg_used = flag_pic && (current_function_uses_pic_offset_table
|| current_function_uses_const_pool);
limit = (frame_pointer_needed
? FRAME_POINTER_REGNUM : STACK_POINTER_REGNUM);
for (regno = limit - 1; regno >= 0; regno--)
if ((regs_ever_live[regno] && !call_used_regs[regno])
|| (regno == PIC_OFFSET_TABLE_REGNUM && pic_reg_used))
{
insn = emit_insn (gen_push (gen_rtx_REG (SImode, regno)));
RTX_FRAME_RELATED_P (insn) = 1;
}
}
/* Expand the prologue into a bunch of separate insns. */
void
ix86_expand_prologue ()
{
register int regno;
int limit;
int pic_reg_used = flag_pic && (current_function_uses_pic_offset_table
|| current_function_uses_const_pool);
HOST_WIDE_INT tsize = ix86_compute_frame_size (get_frame_size (), (int *)0);
......@@ -1664,15 +1732,7 @@ ix86_expand_prologue ()
CALL_INSN_FUNCTION_USAGE (insn));
}
limit = (frame_pointer_needed ? FRAME_POINTER_REGNUM : STACK_POINTER_REGNUM);
for (regno = limit - 1; regno >= 0; regno--)
if ((regs_ever_live[regno] && ! call_used_regs[regno])
|| (regno == PIC_OFFSET_TABLE_REGNUM && pic_reg_used))
{
insn = emit_insn (gen_push (gen_rtx_REG (SImode, regno)));
RTX_FRAME_RELATED_P (insn) = 1;
}
ix86_emit_save_regs ();
#ifdef SUBTARGET_PROLOGUE
SUBTARGET_PROLOGUE;
#endif
......@@ -1687,14 +1747,80 @@ ix86_expand_prologue ()
emit_insn (gen_blockage ());
}
/* Emit code to pop all registers from stack. */
static void
ix86_emit_restore_regs ()
{
int pic_reg_used = flag_pic && (current_function_uses_pic_offset_table
|| current_function_uses_const_pool);
int limit = (frame_pointer_needed
? FRAME_POINTER_REGNUM : STACK_POINTER_REGNUM);
int regno;
for (regno = 0; regno < limit; regno++)
if ((regs_ever_live[regno] && !call_used_regs[regno])
|| (regno == PIC_OFFSET_TABLE_REGNUM && pic_reg_used))
{
emit_insn (gen_popsi1 (gen_rtx_REG (SImode, regno)));
}
}
/* Emit code to add TSIZE to esp value. Use POP instruction when
profitable. */
static void
ix86_emit_epilogue_esp_adjustment (tsize)
int tsize;
{
/* Intel's docs say that for 4 or 8 bytes of stack frame one should
use `pop' and not `add'. */
int use_pop = tsize == 4;
rtx edx = 0, ecx;
/* Use two pops only for the Pentium processors. */
if (tsize == 8 && !TARGET_386 && !TARGET_486)
{
rtx retval = current_function_return_rtx;
edx = gen_rtx_REG (SImode, 1);
/* This case is a bit more complex. Since we cannot pop into
%ecx twice we need a second register. But this is only
available if the return value is not of DImode in which
case the %edx register is not available. */
use_pop = (retval == NULL
|| !reg_overlap_mentioned_p (edx, retval));
}
if (use_pop)
{
ecx = gen_rtx_REG (SImode, 2);
/* We have to prevent the two pops here from being scheduled.
GCC otherwise would try in some situation to put other
instructions in between them which has a bad effect. */
emit_insn (gen_blockage ());
emit_insn (gen_popsi1 (ecx));
if (tsize == 8)
emit_insn (gen_popsi1 (edx));
}
else
{
/* If there is no frame pointer, we must still release the frame. */
emit_insn (gen_addsi3 (stack_pointer_rtx, stack_pointer_rtx,
GEN_INT (tsize)));
}
}
/* Restore function stack, frame, and registers. */
void
ix86_expand_epilogue ()
{
register int regno;
register int limit;
int regno;
int nregs;
int limit;
int pic_reg_used = flag_pic && (current_function_uses_pic_offset_table
|| current_function_uses_const_pool);
int sp_valid = !frame_pointer_needed || current_function_sp_is_unchanging;
......@@ -1710,9 +1836,6 @@ ix86_expand_epilogue ()
less work than reloading sp and popping the register. Otherwise,
restore sp (if necessary) and pop the registers. */
limit = (frame_pointer_needed
? FRAME_POINTER_REGNUM : STACK_POINTER_REGNUM);
if (nregs > 1 || sp_valid)
{
if ( !sp_valid )
......@@ -1724,15 +1847,12 @@ ix86_expand_epilogue ()
emit_insn (gen_rtx_SET (VOIDmode, stack_pointer_rtx, addr_offset));
}
for (regno = 0; regno < limit; regno++)
if ((regs_ever_live[regno] && ! call_used_regs[regno])
|| (regno == PIC_OFFSET_TABLE_REGNUM && pic_reg_used))
{
emit_insn (gen_popsi1 (gen_rtx_REG (SImode, regno)));
}
ix86_emit_restore_regs ();
}
else
{
limit = (frame_pointer_needed
? FRAME_POINTER_REGNUM : STACK_POINTER_REGNUM);
for (regno = 0; regno < limit; regno++)
if ((regs_ever_live[regno] && ! call_used_regs[regno])
|| (regno == PIC_OFFSET_TABLE_REGNUM && pic_reg_used))
......@@ -1756,46 +1876,7 @@ ix86_expand_epilogue ()
}
}
else if (tsize)
{
/* Intel's docs say that for 4 or 8 bytes of stack frame one should
use `pop' and not `add'. */
int use_pop = tsize == 4;
rtx edx = 0, ecx;
/* Use two pops only for the Pentium processors. */
if (tsize == 8 && !TARGET_386 && !TARGET_486)
{
rtx retval = current_function_return_rtx;
edx = gen_rtx_REG (SImode, 1);
/* This case is a bit more complex. Since we cannot pop into
%ecx twice we need a second register. But this is only
available if the return value is not of DImode in which
case the %edx register is not available. */
use_pop = (retval == NULL
|| ! reg_overlap_mentioned_p (edx, retval));
}
if (use_pop)
{
ecx = gen_rtx_REG (SImode, 2);
/* We have to prevent the two pops here from being scheduled.
GCC otherwise would try in some situation to put other
instructions in between them which has a bad effect. */
emit_insn (gen_blockage ());
emit_insn (gen_popsi1 (ecx));
if (tsize == 8)
emit_insn (gen_popsi1 (edx));
}
else
{
/* If there is no frame pointer, we must still release the frame. */
emit_insn (gen_addsi3 (stack_pointer_rtx, stack_pointer_rtx,
GEN_INT (tsize)));
}
}
ix86_emit_epilogue_esp_adjustment (tsize);
#ifdef FUNCTION_BLOCK_PROFILER_EXIT
if (profile_block_flag == 2)
......
gcc/config/i386/i386.h
......@@ -1419,30 +1419,7 @@ do { \
its replacement, at the start of a routine. */
#define INITIAL_ELIMINATION_OFFSET(FROM, TO, OFFSET) \
{ \
if ((FROM) == ARG_POINTER_REGNUM && (TO) == FRAME_POINTER_REGNUM) \
(OFFSET) = 8; /* Skip saved PC and previous frame pointer */ \
else \
{ \
int nregs; \
int offset; \
int preferred_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT; \
HOST_WIDE_INT tsize = ix86_compute_frame_size (get_frame_size (), \
&nregs); \
\
(OFFSET) = (tsize + nregs * UNITS_PER_WORD); \
\
offset = 4; \
if (frame_pointer_needed) \
offset += UNITS_PER_WORD; \
\
if ((FROM) == ARG_POINTER_REGNUM) \
(OFFSET) += offset; \
else \
(OFFSET) -= ((offset + preferred_alignment - 1) \
& -preferred_alignment) - offset; \
} \
}
(OFFSET) = ix86_initial_elimination_offset (FROM, TO)
/* Addressing modes, and classification of registers for them. */
......
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