misc fix

3 files changed, 55 insertions, 18 deletions

diff --git a/ir.c b/ir.c
index d1f3ec9..a42bf55 100644
--- a/ir.c
+++ b/ir.c
@@ -250,7 +250,7 @@ newinstr(void)
       assert(ninstr < arraylength(instrtab));
       t = ninstr++;
    }
-   if (instrnuse[t] > 2)
+   if (instrnuse[t] > arraylength(*instrusebuf))
       xbfree(instruse[t]);
    instruse[t] = instrusebuf[t];
    instrnuse[t] = 0;
@@ -261,12 +261,12 @@ void
 adduse(struct block *ublk, int ui, union ref r) {
    struct use user = { ublk, ui };
    if (r.t != RTMP) return;
-   if (instrnuse[r.i] < 2) {
+   if (instrnuse[r.i] < arraylength(*instrusebuf)) {
       instruse[r.i][instrnuse[r.i]++] = user;
    } else if (instrnuse[r.i] == arraylength(*instrusebuf)) {
       struct use *use = NULL;
       xbgrow(&use, arraylength(*instrusebuf) + 2);
-      memcpy(use, instruse[r.i], arraylength(*instrusebuf) * sizeof *use);
+      memcpy(use, instruse[r.i], sizeof(*instrusebuf));
       use[instrnuse[r.i]++] = user;
       instruse[r.i] = use;
    } else {
@@ -274,6 +274,30 @@ adduse(struct block *ublk, int ui, union ref r) {
    }
 }
 
+bool
+deluse(struct block *ublk, int ui, union ref r) {
+   if (r.t != RTMP) return 0;
+
+   for (int i = 0; i < instrnuse[r.i]; ++i) {
+      if (instruse[r.i][i].blk == ublk && instruse[r.i][i].u == ui) {
+         for (int k = i; k < instrnuse[r.i] - 1; ++k) {
+            instruse[r.i][k] = instruse[r.i][k+1];
+         }
+         goto Shrink;
+      }
+   }
+   return 0;
+
+Shrink:
+   if (instrnuse[r.i] == arraylength(*instrusebuf) + 1) {
+      struct use *use = instruse[r.i];
+      instruse[r.i] = instrusebuf[r.i];
+      memcpy(instruse[r.i], use, sizeof *instrusebuf);
+   }
+   --instrnuse[r.i];
+   return 1;
+}
+
 union ref
 insertinstr(struct block *blk, int idx, struct instr ins)
 {
@@ -310,7 +334,7 @@ insertphi(struct block *blk, enum irclass cls)
 
 /* require use */
 void
-replcins(union ref from, union ref to)
+replcuses(union ref from, union ref to)
 {
    struct use *use, *uend;
 
@@ -333,7 +357,9 @@ replcins(union ref from, union ref to)
       
       for (i = 0; i < n; ++i) {
          if (u[i].bits == from.bits) {
+            deluse(use->blk, use->u, u[i]);
             u[i].bits = to.bits;
+            adduse(use->blk, use->u, u[i]);
             break;
          }
       }
@@ -361,6 +387,19 @@ delinstr(struct block *blk, int idx)
    --blk->ins.n;
 }
 
+void
+delphi(struct block *blk, int idx)
+{
+   int t = blk->phi.p[idx];
+   assert(idx >= 0 && idx < blk->phi.n);
+   memcpy(&instrtab[t], &instrfreelist, sizeof(int));
+   instrfreelist = t;
+   deluses(t);
+   for (int i = idx; i < blk->phi.n; ++i)
+      blk->phi.p[i] = blk->phi.p[i + 1];
+   --blk->phi.n;
+}
+
 /** IR builders **/
 
 struct block *
diff --git a/ir.h b/ir.h
index 45a64a2..a8b3356 100644
--- a/ir.h
+++ b/ir.h
@@ -228,9 +228,10 @@ union ref mkaddr(struct addr);
 void adduse(struct block *ublk, int ui, union ref r);
 union ref insertinstr(struct block *, int idx, struct instr);
 union ref insertphi(struct block *, enum irclass cls);
-void replcins(union ref from, union ref to);
+void replcuses(union ref from, union ref to);
 void deluses(int ins);
 void delinstr(struct block *, int idx);
+void delphi(struct block *, int idx);
 #define blkpred(blk, i) 0[(blk)->npred < 2 ? &(blk)->_pred0 : &(blk)->_pred[i]]
 
 /* IR builder functions */
diff --git a/optmem.c b/optmem.c
index c9b4536..b5eaae4 100644
--- a/optmem.c
+++ b/optmem.c
@@ -49,25 +49,22 @@ deltrivialphis(struct block *blk, union ref phiref)
       same = UNDREF; /* the phi is unreachable or in the start block */
 
    /* replace uses */
-   replcins(phiref, same);
+   replcuses(phiref, same);
 
-   /* remove phi */
-   for (int i = 0; i < blk->phi.n; ++i) {
-      if (blk->phi.p[i] == phiref.i) {
-         for (int k = i; k < blk->phi.n - 1; ++k)
-            blk->phi.p[k] = blk->phi.p[k + 1];
-         --blk->phi.n;
-         break;
-      }
-   }
    instrtab[phiref.i].op = Onop;
 
    /* recursively try to remove all phi users as they might have become trivial */
    for (use = instruse[phiref.i], uend = use + instrnuse[phiref.i]; use < uend; ++use)
-      if (use->u != USERJUMP && instrtab[use->u].op == Ophi && use->u != phiref.i)
+      if (use->u != USERJUMP && instrtab[use->u].op == Ophi)
          deltrivialphis(use->blk, mkref(RTMP, use->u));
 
-   deluses(phiref.i);
+   /* remove phi */
+   for (int i = 0; i < blk->phi.n; ++i) {
+      if (blk->phi.p[i] == phiref.i) {
+         delphi(blk, i);
+         break;
+      }
+   }
    return same;
 }
 
@@ -187,7 +184,7 @@ mem2reg(struct function *fn)
             }
          }
          /* remove alloca */
-         delinstr(blk, i);
+         delinstr(blk, i--);
          
       Next:;
       }