I think this is the right 'ok()' heuristic.

2 files changed, 20 insertions, 11 deletions

diff --git a/6/isel.c b/6/isel.c
index 0833e16..78a3568 100644
--- a/6/isel.c
+++ b/6/isel.c
@@ -699,8 +699,8 @@ void iprintf(FILE *fd, Insn *insn)
             if (insn->args[0]->mode != insn->args[1]->mode)
                 insn->args[0] = coreg(insn->args[0]->reg.colour, insn->args[1]->mode);
             /* moving a reg to itself is dumb. */
-            if (insn->args[0]->reg.colour == insn->args[1]->reg.colour)
-                return;
+     //       if (insn->args[0]->reg.colour == insn->args[1]->reg.colour)
+     //           return;
             break;
         default:
             break;
diff --git a/6/ra.c b/6/ra.c
index 71c5b77..b6a917d 100644
--- a/6/ra.c
+++ b/6/ra.c
@@ -636,13 +636,13 @@ static int conservative(Isel *s, regid u, regid v)
 /* FIXME: is this actually correct? */
 static int ok(Isel *s, regid t, regid r)
 {
-    if (s->degree[t] >= K)
-        return 0;
-    if (!bshas(s->prepainted, t))
-        return 0;
-    if (!gbhasedge(s, t, r))
-        return 0;
-    return 1;
+    if (s->degree[t] < K)
+        return 1;
+    if (bshas(s->prepainted, t))
+        return 1;
+    if (gbhasedge(s, t, r))
+        return 1;
+    return 0;
 }
 
 static int combinable(Isel *s, regid u, regid v)
@@ -674,7 +674,7 @@ static void combine(Isel *s, regid u, regid v)
     size_t i, j;
     int has;
 
-    if (debugopt['r'] || 1)
+    if (debugopt['r'])
         printedge(stdout, "combining:", u, v);
     if (wlhas(s->wlfreeze, s->nwlfreeze, v, &idx))
         ldel(&s->wlfreeze, &s->nwlfreeze, idx);
@@ -698,7 +698,7 @@ static void combine(Isel *s, regid u, regid v)
     }
 
     for (t = 0; adjiter(s, v, &t); t++) {
-        if (debugopt['r'] || 1)
+        if (debugopt['r'])
             printedge(stdout, "combine-putedge:", v, t);
         addedge(s, t, u);
         decdegree(s, t);
@@ -1317,3 +1317,12 @@ void edges(Isel *s, regid u)
     }
     printf("\n");
 }
+
+void whichwl(Isel *s, regid r)
+{
+  size_t o;
+  if (wlhas(s->wlspill, s->nwlspill, r, &o)) printf("on spill\n");
+  if (wlhas(s->wlsimp, s->nwlsimp, r, &o)) printf("on simp\n");
+  if (wlhas(s->wlfreeze, s->nwlfreeze, r, &o)) printf("on freeze\n");
+  if (wlhas(s->selstk, s->nselstk, r, &o)) printf("on selstk\n");
+}