bug fixes: put header block at end of procedure

This commit is contained in:
ceriel 1987-08-04 14:13:24 +00:00
parent d34064d660
commit 159b84ef68
2 changed files with 53 additions and 15 deletions

View file

@ -15,6 +15,7 @@
#include "../../../h/em_mnem.h"
#include "../share/debug.h"
#include "../share/alloc.h"
#include "../share/def.h"
#include "../share/global.h"
#include "../share/aux.h"
#include "sr_aux.h"
@ -26,6 +27,7 @@
#include "../../../h/em_reg.h"
#include "../../../h/em_mes.h"
#include "../../../h/em_mnem.h"
#include "../../../h/em_spec.h"
@ -403,7 +405,39 @@ STATIC code_p available(c,vars)
return (code_p) 0;
}
STATIC fix_header(lp)
loop_p lp;
{
/* Check if a header block was added, and if so, add a branch to
* the entry block.
* If it was added, it was added to the end of the procedure, so
* move the END pseudo.
*/
bblock_p b = curproc->p_start;
if (lp->LP_HEADER->b_next == 0) {
line_p l = last_instr(lp->LP_HEADER);
line_p e;
assert(l != 0);
if (INSTR(l) != op_bra) {
line_p j = newline(OPINSTRLAB);
assert(INSTR(lp->lp_entry->b_start) == op_lab);
INSTRLAB(j) = INSTRLAB(lp->lp_entry->b_start);
j->l_instr = op_bra;
DLINK(l, j);
l = j;
}
while (b->b_next != lp->LP_HEADER) b = b->b_next;
e = last_instr(b);
assert(INSTR(e) == ps_end);
assert(PREV(e) != 0);
PREV(e)->l_next = 0;
DLINK(l, e);
}
}
STATIC reduce(code,vars)
code_p code;
@ -456,6 +490,7 @@ STATIC reduce(code,vars)
incr_code(code,tmp); /* emit code to increment temp. local */
OUTTRACE("emitted increment code",0);
Ladd(code,&avail);
fix_header(code->co_loop);
}
}

View file

@ -93,12 +93,17 @@ STATIC lab_id label(b)
line_p l;
assert (b->b_start != (line_p) 0);
if (INSTR(b->b_start) == op_lab) return INSTRLAB(b->b_start);
if (b->b_start && INSTR(b->b_start) == op_lab) {
return INSTRLAB(b->b_start);
}
/* The block has no label yet. */
l = newline(OPINSTRLAB);
l->l_instr = op_lab;
INSTRLAB(l) = freshlabel();
if (b->b_start) {
DLINK(l,b->b_start); /* doubly link them */
}
b->b_start = l;
return INSTRLAB(l);
}
@ -150,6 +155,9 @@ make_header(lp)
* the loop to the entry block now goes to b.
*/
b->b_succ = Lempty_set();
b->b_pred = Lempty_set();
for (i = Lfirst(entry->b_pred); i != (Lindex) 0; i = next ) {
next = Lnext(i,entry->b_pred);
c = (bblock_p) Lelem(i);
@ -159,23 +167,18 @@ make_header(lp)
Lremove(c,&entry->b_pred);
Lremove(entry,&c->b_succ);
Ladd(b,&c->b_succ);
Ladd(c,&b->b_pred);
adjust_jump(b,entry,c);
}
}
assert(lp->LP_INSTR == 0);
lp->LP_INSTR = b->b_start;
Ladd(b,&entry->b_pred);
b->b_succ = Lempty_set();
b->b_pred = Lempty_set();
Ladd(entry,&b->b_succ);
if (curproc->p_start == entry) {
/* entry was the first block of curproc */
curproc->p_start = b;
} else {
/* find block before entry block */
for (c = curproc->p_start; c->b_next != entry; c = c->b_next);
/* put header block at end of procedure */
for (c = curproc->p_start; c->b_next != 0; c = c->b_next);
c->b_next = b;
Ladd(c,&b->b_pred);
}
b->b_next = entry;
/* b->b_next = 0; */
copy_loops(b,entry,lp);
b->b_idom = entry->b_idom;
entry->b_idom = b;