bug fixes: put header block at end of procedure

diff --git a/util/ego/sr/sr_reduce.c b/util/ego/sr/sr_reduce.c
index ecf617d..2d287ff 100644 (file)
--- a/util/ego/sr/sr_reduce.c
+++ b/util/ego/sr/sr_reduce.c
@@ -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);
        }
 }
 

diff --git a/util/ego/sr/sr_xform.c b/util/ego/sr/sr_xform.c
index dcc1106..2b10e0e 100644 (file)
--- a/util/ego/sr/sr_xform.c
+++ b/util/ego/sr/sr_xform.c
@@ -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();
-       DLINK(l,b->b_start); /* doubly link them */
+       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);
-               c->b_next = b;
-               Ladd(c,&b->b_pred);
-       }
-       b->b_next = entry;
+       /* put header block at end of procedure */
+       for (c = curproc->p_start; c->b_next != 0; c = c->b_next);
+       c->b_next = b;
+       /* b->b_next = 0; */
        copy_loops(b,entry,lp);
        b->b_idom = entry->b_idom;
        entry->b_idom = b;