ack/mach/powerpc/mcg/platform.c
David Given b5c1d622f5 Rework the way stack frames are laid out to be simpler and, hopefully, more
correct. Saved registers are now placed in what may be the right place.
2016-11-11 21:17:45 +01:00

334 lines
9.6 KiB
C

#include "mcg.h"
/* mcg stack frames are laid out as:
*
* | ...params...
* | --------------- <- ab
* | old FR
* | old FP
* | --------------- <- fp (a.k.a. lb)
* | locals
* | ---------------
* | spills
* | --------------- <- sb
* | saved regs
* | --------------- <- sp, rb
* V ...user area...
*
* st indexes up; lb indexes down.
*
* Note that [fp] == old_fp and ab == fp + 8.
*/
static ARRAYOF(struct hreg) saved_regs;
void platform_calculate_offsets(void)
{
int i;
saved_regs.count = 0;
for (i=0; i<current_proc->usedregs.count; i++)
{
struct hreg* hreg = current_proc->usedregs.item[i];
if (!(hreg->attrs & burm_volatile_ATTR) &&
((hreg->attrs & burm_long_ATTR) || (hreg->attrs & burm_double_ATTR)))
{
hreg->offset = current_proc->saved_size;
current_proc->saved_size += 8;
array_append(&saved_regs, hreg);
}
}
for (i=0; i<current_proc->usedregs.count; i++)
{
struct hreg* hreg = current_proc->usedregs.item[i];
if (!(hreg->attrs & burm_volatile_ATTR) &&
((hreg->attrs & burm_int_ATTR) || (hreg->attrs & burm_float_ATTR)))
{
hreg->offset = current_proc->saved_size;
current_proc->saved_size += 4;
array_append(&saved_regs, hreg);
}
}
current_proc->fp_to_ab = 8;
current_proc->fp_to_lb = 0;
current_proc->fp_to_sb = -(current_proc->locals_size + current_proc->spills_size);
current_proc->fp_to_rb = current_proc->fp_to_sb - current_proc->saved_size;
}
struct hop* platform_prologue(void)
{
int i;
int saved_offset;
int spoffset = current_proc->saved_size + current_proc->spills_size +
current_proc->locals_size;
struct hop* hop = new_hop(current_proc->entry, NULL);
hop_add_insel(hop, "! params @ fp+%d", current_proc->fp_to_ab);
hop_add_insel(hop, "! lr @ fp+4");
hop_add_insel(hop, "! fp @ fp+0");
hop_add_insel(hop, "! locals @ fp-%d to fp+0",
current_proc->locals_size);
hop_add_insel(hop, "! spills @ fp-%d to fp-%d",
-current_proc->fp_to_sb, current_proc->locals_size);
for (i=0; i<saved_regs.count; i++)
{
struct hreg* hreg = saved_regs.item[i];
hop_add_insel(hop, "! %s @ fp-%d",
hreg->id, -(current_proc->fp_to_rb + hreg->offset));
}
hop_add_insel(hop, "addi sp, sp, %d", -(spoffset + 8));
hop_add_insel(hop, "mfspr r0, lr");
hop_add_insel(hop, "stw fp, %d(sp)", spoffset + 0);
hop_add_insel(hop, "stw r0, %d(sp)", spoffset + 4);
hop_add_insel(hop, "addi fp, sp, %d", spoffset);
/* Saved reg offsets are negative. */
saved_offset = -(current_proc->locals_size + current_proc->spills_size);
for (i=0; i<saved_regs.count; i++)
{
struct hreg* hreg = saved_regs.item[i];
if (hreg->attrs & burm_int_ATTR)
hop_add_insel(hop, "stw %H, %d(fp)",
hreg, current_proc->fp_to_rb + saved_offset);
else if (hreg->attrs & burm_float_ATTR)
hop_add_insel(hop, "stfs %H, %d(fp)",
hreg, current_proc->fp_to_rb + saved_offset);
}
return hop;
}
struct hop* platform_epilogue(void)
{
struct hop* hop = new_hop(current_proc->exit, NULL);
int i;
int saved_offset;
for (i=0; i<saved_regs.count; i++)
{
struct hreg* hreg = saved_regs.item[i];
if (hreg->attrs & burm_int_ATTR)
hop_add_insel(hop, "lwz %H, %d(fp)",
hreg, current_proc->fp_to_rb + saved_offset);
else if (hreg->attrs & burm_float_ATTR)
hop_add_insel(hop, "lfs %H, %d(fp)",
hreg, current_proc->fp_to_rb + saved_offset);
}
hop_add_insel(hop, "lwz r0, 4(fp)");
hop_add_insel(hop, "mtspr lr, r0");
hop_add_insel(hop, "lwz r0, 0(fp)"); /* load old fp */
hop_add_insel(hop, "addi sp, fp, %d", current_proc->fp_to_ab);
hop_add_insel(hop, "mr fp, r0");
hop_add_insel(hop, "bclr 20, 0, 0");
return hop;
}
struct hop* platform_move(struct basicblock* bb, struct hreg* src, struct hreg* dest)
{
struct hop* hop = new_hop(bb, NULL);
if ((src->attrs & TYPE_ATTRS) != (dest->attrs & TYPE_ATTRS))
{
assert(!src->is_stacked);
assert(!dest->is_stacked);
switch (src->attrs & TYPE_ATTRS)
{
case burm_int_ATTR:
hop_add_insel(hop, "stwu %H, -4(sp)", src);
break;
case burm_long_ATTR:
hop_add_insel(hop, "stwu %0H, -4(sp)", src);
hop_add_insel(hop, "stwu %1H, -4(sp)", src);
break;
case burm_float_ATTR:
hop_add_insel(hop, "stfsu %H, -4(sp)", src);
break;
case burm_double_ATTR:
hop_add_insel(hop, "stfdu %H, -8(sp)", src);
break;
default:
goto nomove;
}
switch (dest->attrs & TYPE_ATTRS)
{
case burm_int_ATTR:
hop_add_insel(hop, "lwz %H, 0(sp)", dest);
break;
case burm_long_ATTR:
hop_add_insel(hop, "lwz %0H, 4(sp)", dest);
hop_add_insel(hop, "lwz %1H, 0(sp)", dest);
break;
case burm_float_ATTR:
hop_add_insel(hop, "lfs %H, 0(sp)", dest);
break;
case burm_double_ATTR:
hop_add_insel(hop, "lfd %H, 0(sp)", dest);
break;
default:
goto nomove;
}
switch (dest->attrs & TYPE_ATTRS)
{
case burm_int_ATTR:
case burm_float_ATTR:
hop_add_insel(hop, "addi sp, sp, 4");
break;
case burm_double_ATTR:
case burm_long_ATTR:
hop_add_insel(hop, "addi sp, sp, 8");
break;
default:
goto nomove;
}
}
else
{
uint32_t type = src->attrs & TYPE_ATTRS;
if (!src->is_stacked && dest->is_stacked)
{
switch (type)
{
case burm_int_ATTR:
hop_add_insel(hop, "stw %H, %S(fp) ! %H", src, dest, dest);
break;
case burm_float_ATTR:
hop_add_insel(hop, "stfs %H, %S(fp) ! %H", src, dest, dest);
break;
case burm_long_ATTR:
hop_add_insel(hop, "stw %0H, 4+%S(fp) ! %H", src, dest, dest);
hop_add_insel(hop, "stw %1H, 0+%S(fp) ! %H", src, dest, dest);
break;
case burm_double_ATTR:
hop_add_insel(hop, "stfd %H, %S(fp) ! %H", src, dest, dest);
break;
default:
goto nomove;
}
}
else if (src->is_stacked && !dest->is_stacked)
{
switch (type)
{
case burm_int_ATTR:
hop_add_insel(hop, "lwz %H, %S(fp) ! %H", dest, src, src);
break;
case burm_float_ATTR:
hop_add_insel(hop, "lfs %H, %S(fp) ! %H", dest, src, src);
break;
case burm_double_ATTR:
hop_add_insel(hop, "lfd %H, %S(fp) ! %H", dest, src, src);
break;
default:
goto nomove;
}
}
else if (!src->is_stacked && !dest->is_stacked)
{
switch (type)
{
case burm_int_ATTR:
hop_add_insel(hop, "mr %H, %H", dest, src);
break;
case burm_long_ATTR:
hop_add_insel(hop, "mr %0H, %0H", dest, src);
hop_add_insel(hop, "mr %1H, %1H", dest, src);
break;
case burm_float_ATTR:
case burm_double_ATTR:
hop_add_insel(hop, "fmr %H, %H", dest, src);
break;
default:
goto nomove;
}
}
else
goto nomove;
}
return hop;
nomove:
fatal("cannot move %s to %s", src->id, dest->id);
}
struct hop* platform_swap(struct basicblock* bb, struct hreg* src, struct hreg* dest)
{
struct hop* hop = new_hop(bb, NULL);
assert(!src->is_stacked);
assert(!dest->is_stacked);
assert((src->attrs & TYPE_ATTRS) == (dest->attrs & TYPE_ATTRS));
switch (src->attrs & TYPE_ATTRS)
{
case burm_int_ATTR:
hop_add_insel(hop, "mr r0, %H", src);
hop_add_insel(hop, "mr %H, %H", src, dest);
hop_add_insel(hop, "mr %H, r0", dest);
break;
case burm_long_ATTR:
hop_add_insel(hop, "mr r0, %0H", src);
hop_add_insel(hop, "mr %0H, %0H", src, dest);
hop_add_insel(hop, "mr %0H, r0", dest);
hop_add_insel(hop, "mr r0, %1H", src);
hop_add_insel(hop, "mr %1H, %1H", src, dest);
hop_add_insel(hop, "mr %1H, r0", dest);
break;
case burm_float_ATTR:
case burm_double_ATTR:
hop_add_insel(hop, "fmr f0, %H", src);
hop_add_insel(hop, "fmr %H, %H", src, dest);
hop_add_insel(hop, "fmr %H, f0", dest);
break;
}
return hop;
}
const char* platform_label(const char* label)
{
/* Labels starting with . are internal, not exported, and don't need mangling. */
if (label[0] == '.')
return label;
/* Otherwise, mangle. */
return aprintf("_%s", label);
}
/* vim: set sw=4 ts=4 expandtab : */