Merge pull request #920 from frodwith/runtime-overflows

Runtime overflows

include/noun/allocate.h

@@ -291,6 +291,22 @@
           void*
           u3a_wealloc(void* lag_v, c3_w len_w);
 
+        /* u3a_push(): allocate space on the road stack
+        */
+          void*
+          u3a_push(c3_w len_w);
+
+        /* u3a_pop(): deallocate space on the road stack
+        */
+          void
+          u3a_pop(c3_w len_w);
+
+        /* u3a_peek(): examine the top of the road stack
+        */
+          void*
+          u3a_peek(c3_w len_w);
+
+
       /* C-style aligned allocation - *not* compatible with above.
       */
         /* u3a_malloc(): aligned storage measured in bytes.

jets/e/jam.c

@@ -3,32 +3,19 @@
 */
 #include "all.h"
 
-
 /* functions
 */
-  static u3_noun
-  _jam_in(u3p(u3h_root) har_p, u3_atom, u3_atom, u3_noun);
 
   static u3_noun
-  _jam_in_pair(u3p(u3h_root) har_p,
+  _jam_pair(u3_noun x, u3_noun d, u3_noun e)
-               u3_atom       h_a,
-               u3_atom       t_a,
-               u3_atom       b,
-               u3_noun       l)
   {
-    u3_noun w = u3nc(u3nc(2, 1), u3k(l));
+    u3_noun r, p_d, q_d, r_d;
-    u3_noun x = u3qa_add(2, b);
+    u3x_trel(d, &p_d, &q_d, &r_d);
-    u3_noun d = _jam_in(har_p, h_a, x, w);
-    u3_noun p_d, q_d, r_d;
-    u3_noun r;
-
-    u3r_trel(d, &p_d, &q_d, &r_d);
     {
       u3_noun y = u3qa_add(x, p_d);
-      u3_noun e = _jam_in(har_p, t_a, y, q_d);
       u3_noun p_e, q_e, r_e;
 
-      u3r_trel(e, &p_e, &q_e, &r_e);
+      u3x_trel(e, &p_e, &q_e, &r_e);
       {
         u3_noun z = u3qa_add(p_d, p_e);
 
@@ -36,20 +23,16 @@
 
         u3z(z);
       }
-      u3z(e);
       u3z(y);
     }
-    u3z(d);
     u3z(x);
-    u3z(w);
+    u3z(d);
-
+    u3z(e);
     return r;
   }
 
   static u3_noun
-  _jam_in_flat(u3p(u3h_root) har_p,
+  _jam_flat(u3_atom a, u3_noun l)
-               u3_atom       a,
-               u3_noun       l)
   {
     u3_noun d = u3qe_mat(a);
     u3_noun x = u3qa_add(1, u3h(d));
@@ -62,9 +45,7 @@
   }
 
   static u3_noun
-  _jam_in_ptr(u3p(u3h_root) har_p,
+  _jam_ptr(u3_atom u_c, u3_noun l)
-              u3_atom       u_c,
-              u3_noun       l)
   {
     u3_noun d = u3qe_mat(u_c);
     u3_atom x = u3qc_lsh(0, 2, u3t(d));
@@ -78,45 +59,97 @@
     return z;
   }
 
-  static u3_noun
+  typedef struct {
-  _jam_in(u3p(u3h_root) har_p,
+    u3_noun  a;
-          u3_noun       a,
+    u3_noun  b;
-          u3_atom       b,
+    u3_noun  l;
-          u3_noun       l)
+    u3_noun* r;
+    u3_noun hed;
+    u3_noun tel;
+  } jamframe;
+
+  static inline void
+  _jam_push(u3_noun a, u3_noun b, u3_noun l, u3_noun *r)
   {
-    u3_noun c = u3h_get(har_p, a);
+    jamframe* fam = u3a_push(sizeof(jamframe));
-    u3_noun x;
+    fam->a   = a;
+    fam->b   = b;
+    fam->l   = l;
+    fam->r   = r;
+    fam->hed = u3_none;
+    fam->tel = u3_none;
+  }
 
-    if ( u3_none == c ) {
+  static inline void
-        u3h_put(har_p, a, u3k(b));
+  _jam_pop()
+  {
+    u3a_pop(sizeof(jamframe));
+  }
 
-      if ( c3y == u3ud(a) ) {
+  static inline jamframe*
-        x = _jam_in_flat(har_p, a, l);
+  _jam_peek()
-      } else {
+  {
-        x = _jam_in_pair(har_p, u3h(a), u3t(a), b, l);
+    return (jamframe*) u3a_peek(sizeof(jamframe));
-      }
-    }
-    else {
-      if ( c3y == u3ud(a) && u3r_met(0, a) <= u3r_met(0, c) ) {
-        x = _jam_in_flat(har_p, a, l);
-      }
-      else {
-        x = _jam_in_ptr(har_p, c, l);
-      }
-    }
-    return x;
   }
 
   u3_noun
   u3qe_jam(u3_atom a)
   {
     u3p(u3h_root) har_p = u3h_new();
+    u3p(jamframe) empty = u3R->cap_p;
+    jamframe* fam;
+    u3_noun out, c, x, q, r;
 
-    u3_noun x = _jam_in(har_p, a, 0, u3_nul);
+    _jam_push(a, 0, u3_nul, &out);
-    u3_noun q = u3qb_flop(u3h(u3t(x)));
+    while ( empty != u3R->cap_p ) {
-    u3_noun r = u3qc_can(0, q);
+      fam  = _jam_peek();
+      if ( u3_none != fam->tel ) {
+        u3_noun z = u3qa_add(2, fam->b);
+        x = _jam_pair(z, fam->hed, fam->tel);
+      }
+      else if ( u3_none != fam->hed ) {
+        u3_noun p_d, q_d, r_d;
+        u3x_trel(fam->hed, &p_d, &q_d, &r_d);
+        {
+          u3_noun z = u3qa_add(2, fam->b);
+          u3_noun y = u3qa_add(z, p_d);
+          _jam_push(u3t(fam->a), y, q_d, &(fam->tel));
+          u3z(z);
+          continue;
+        }
+      }
+      else {
+        a = fam->a;
+        c = u3h_get(har_p, a);
+        if ( u3_none != c ) {
+          if ( (c3y == u3ud(a)) && u3r_met(0, a) <= u3r_met(0, c) ) {
+            x = _jam_flat(a, fam->l);
+          }
+          else {
+            x = _jam_ptr(c, fam->l);
+          }
+        }
+        else {
+          u3h_put(har_p, a, u3k(fam->b));
+          if ( c3y == u3ud(a) ) {
+            x = _jam_flat(a, fam->l);
+          }
+          else {
+            u3_noun z = u3qa_add(2, fam->b);
+            u3_noun w = u3nc(u3nc(2, 1), u3k(fam->l));
+            _jam_push(u3h(a), z, w, &(fam->hed));
+            continue;
+          }
+        }
+      }
+      *(fam->r) = x;
+      u3z(fam->b);
+      _jam_pop();
+    }
 
-    u3z(x);
+    q = u3qb_flop(u3h(u3t(out)));
+    r = u3qc_can(0, q);
+    u3z(out);
     u3z(q);
     u3h_free(har_p);
     return r;

noun/allocate.c

@@ -576,6 +576,58 @@ u3a_wealloc(void* lag_v, c3_w len_w)
     }
   }
 }
+/* u3a_push(): allocate space on the road stack
+*/
+void*
+u3a_push(c3_w len_w)
+{
+  void *cur, *top = u3to(void, u3R->cap_p);
+  if ( c3y == u3a_is_north(u3R) ) {
+    top -= len_w;
+    cur = top;
+    u3p(void) cap_p = u3R->cap_p = u3of(void, top);
+    c3_assert(cap_p < u3R->mat_p);
+    c3_assert(cap_p > u3R->hat_p);
+    return cur;
+  }
+  else {
+    cur = top;
+    top += len_w;
+    u3R->cap_p = u3of(void, top);
+    u3p(void) cap_p = u3R->cap_p = u3of(void, top);
+    c3_assert(cap_p > u3R->mat_p);
+    c3_assert(cap_p < u3R->hat_p);
+    return cur;
+  }
+}
+
+/* u3a_pop(): deallocate space on the road stack
+*/
+void
+u3a_pop(c3_w len_w)
+{
+  void* top = u3to(void, u3R->cap_p);
+  if ( c3y == u3a_is_north(u3R) ) {
+    top += len_w;
+    u3p(void) cap_p = u3R->cap_p = u3of(void, top);
+    c3_assert(cap_p <= u3R->mat_p);
+    c3_assert(cap_p > u3R->hat_p);
+  }
+  else {
+    top -= len_w;
+    u3p(void) cap_p = u3R->cap_p = u3of(void, top);
+    c3_assert(cap_p >= u3R->mat_p);
+    c3_assert(cap_p < u3R->hat_p);
+  }
+}
+
+/* u3a_peek(): examine the top of the road stack
+*/
+void*
+u3a_peek(c3_w len_w)
+{
+  return u3to(void, u3R->cap_p) - (c3y == u3a_is_north(u3R) ? 0 : len_w);
+}
 
 /* u3a_wfree(): free storage.
 */

noun/retrieve.c

@@ -502,87 +502,39 @@ _sang_one(u3_noun* a, u3_noun* b)
   }
 }
 
-/* _sang_x(): yes if a and b are the same noun, unifying but leaking.
+typedef struct {
+  u3_noun  a;
+  u3_noun  b;
+  c3_y sat_y;
+} eqframe;
+
+static inline eqframe*
+_eq_peek()
+{
+  return (eqframe*) u3a_peek(sizeof(eqframe));
+}
+
+static inline void
+_eq_push(u3_noun a, u3_noun b)
+{
+  eqframe* cur = (eqframe*) u3a_push(sizeof(eqframe));
+  cur->a       = a;
+  cur->b       = b;
+  cur->sat_y   = 0;
+}
+
+static inline void
+_eq_pop()
+{
+  u3a_pop(sizeof(eqframe));
+}
+
+/* _sing_one(): do not pick a unified pointer for identical (a) and (b).
 */
-static c3_o
+static void
-_sang_x(u3_noun a, u3_noun b)
+_sing_one(u3_noun* a, u3_noun* b)
 {
-  if ( a == b ) {
+  // this space left intentionally blank
-    return c3y;
-  }
-  else {
-    if ( _(u3a_is_atom(a)) ) {
-      u3a_atom* a_u = u3a_to_ptr(a);
-
-      if ( !_(u3a_is_atom(b)) ||
-           _(u3a_is_cat(a)) ||
-           _(u3a_is_cat(b)) )
-      {
-        return c3n;
-      }
-      else {
-        u3a_atom* b_u = u3a_to_ptr(b);
-
-        if ( a_u->mug_w &&
-             b_u->mug_w &&
-             (a_u->mug_w != b_u->mug_w) )
-        {
-          return c3n;
-        }
-        else {
-          c3_w w_rez = a_u->len_w;
-          c3_w w_mox = b_u->len_w;
-
-          if ( w_rez != w_mox ) {
-            return c3n;
-          }
-          else {
-            c3_w i_w;
-
-            for ( i_w = 0; i_w < w_rez; i_w++ ) {
-              if ( a_u->buf_w[i_w] != b_u->buf_w[i_w] ) {
-                return c3n;
-              }
-            }
-            return c3y;
-          }
-        }
-      }
-    }
-    else {
-      if ( _(u3a_is_atom(b)) ) {
-        return c3n;
-      }
-      else {
-        u3a_cell* a_u = u3a_to_ptr(a);
-        u3a_cell* b_u = u3a_to_ptr(b);
-
-        if ( a_u->mug_w &&
-             b_u->mug_w &&
-             (a_u->mug_w != b_u->mug_w) )
-        {
-          return c3n;
-        }
-        else {
-          if ( c3n == _sang_x(a_u->hed, b_u->hed) ) {
-            return c3n;
-          }
-          else {
-            _sang_one(&a_u->hed, &b_u->hed);
-
-            if ( c3n == _sang_x(a_u->tel, b_u->tel) ) {
-              return c3n;
-            }
-            else {
-              _sang_one(&a_u->tel, &b_u->tel);
-
-              return c3y;
-            }
-          }
-        }
-      }
-    }
-  }
 }
 
 /* _sung_one(): pick a unified pointer for identical (a) and (b).
@@ -669,16 +621,9 @@ _sung_one(u3_noun* a, u3_noun* b)
   }
 }
 
-/* _sung_x(): yes if a and b are the same noun, unifying.
+static inline c3_o
-*/
+_song_atom(u3_atom a, u3_atom b)
-static c3_o
-_sung_x(u3_noun a, u3_noun b)
 {
-  if ( a == b ) {
-    return c3y;
-  }
-  else {
-    if ( _(u3a_is_atom(a)) ) {
   u3a_atom* a_u = u3a_to_ptr(a);
 
   if ( !_(u3a_is_atom(b)) ||
@@ -711,134 +656,118 @@ _sung_x(u3_noun a, u3_noun b)
             return c3n;
           }
         }
+      }
+    }
+  }
   return c3y;
 }
-        }
-      }
-    }
-    else {
-      if ( _(u3a_is_atom(b)) ) {
-        return c3n;
-      }
-      else {
-        u3a_cell* a_u = u3a_to_ptr(a);
-        u3a_cell* b_u = u3a_to_ptr(b);
 
-        if ( a_u->mug_w &&
+/* knob: set lower to get more/earlier memoize-by-pointer,
-             b_u->mug_w &&
+ *       higher to avoid allocating the u3h as often */
-             (a_u->mug_w != b_u->mug_w) )
+#define EQ_WHISTLE 1024
-        {
-          return c3n;
-        }
-        else {
-          if ( c3n == _sung_x(a_u->hed, b_u->hed) ) {
-            return c3n;
-          }
-          else {
-            _sung_one(&a_u->hed, &b_u->hed);
 
-            if ( c3n == _sung_x(a_u->tel, b_u->tel) ) {
+/* _song_x(): yes if a and b are the same noun, use uni to unify
-              return c3n;
-            }
-            else {
-              _sung_one(&a_u->tel, &b_u->tel);
-
-              return c3y;
-            }
-          }
-        }
-      }
-    }
-  }
-}
-
-/* _sing_x():
-**
-**   Yes iff (a) and (b) are the same noun.
 */
 static c3_o
-_sing_x(u3_noun a,
+_song_x(u3_noun a, u3_noun b, void (*uni)(u3_noun*, u3_noun*))
-        u3_noun b)
 {
-  c3_assert(u3_none != a);
+  eqframe* fam;
-  c3_assert(u3_none != b);
+  u3p(eqframe) empty = u3R->cap_p;
+  c3_w wis_w = 0;
+  c3_o r_o = c3n;
+  u3p(u3h_root) har_p = 0;
 
-  if ( a == b ) {
+  _eq_push(a, b);
-    return c3y;
+  /* there's a while and a switch here. continues all mean "do the loop again"
+  ** and breaks all mean "fall through this switch case". There are no breaks
+  ** that early terminate the loop.
+  */
+  while ( empty != u3R->cap_p ) {
+    fam = _eq_peek();
+    if ( (a = fam->a) == (b = fam->b) ) {
+      r_o = c3y;
     }
-  else {
+    else if ( c3y == u3a_is_atom(a) ) {
-    if ( _(u3a_is_atom(a)) ) {
+      r_o = _song_atom(a, b);
-      u3a_atom* a_u = u3a_to_ptr(a);
-
-      if ( !_(u3a_is_atom(b)) ||
-           _(u3a_is_cat(a)) ||
-           _(u3a_is_cat(b)) )
-      {
-        return c3n;
     }
-      else {
+    else if ( c3y == u3a_is_atom(b) ) {
-        u3a_atom* b_u = u3a_to_ptr(b);
+      r_o = c3n;
-
-        if ( a_u->mug_w &&
-             b_u->mug_w &&
-             (a_u->mug_w != b_u->mug_w) )
-        {
-          return c3n;
-        }
-        else {
-          c3_w w_rez = a_u->len_w;
-          c3_w w_mox = b_u->len_w;
-
-          if ( w_rez != w_mox ) {
-            return c3n;
-          }
-          else {
-            c3_w i_w;
-
-            for ( i_w = 0; i_w < w_rez; i_w++ ) {
-              if ( a_u->buf_w[i_w] != b_u->buf_w[i_w] ) {
-                return c3n;
-              }
-            }
-            return c3y;
-          }
-        }
-      }
-    }
-    else {
-      if ( _(u3a_is_atom(b)) ) {
-        return c3n;
     }
     else {
       u3a_cell* a_u = u3a_to_ptr(a);
       u3a_cell* b_u = u3a_to_ptr(b);
 
+      switch ( fam->sat_y ) {
+        case 2:
+          uni(&(a_u->tel), &(b_u->tel));
+          r_o = c3y;
+          break;
+
+        case 1:
+          uni(&(a_u->hed), &(b_u->hed));
+          _eq_push(a_u->tel, b_u->tel);
+          fam->sat_y = 2;
+          continue;
+
+        case 0: {
           if ( a_u->mug_w &&
                b_u->mug_w &&
-             (a_u->mug_w != b_u->mug_w) )
+               (a_u->mug_w != b_u->mug_w) ) {
-        {
+            r_o = c3n;
+            break;
+          }
+          else {
+            if ( har_p != 0 ) {
+              u3_noun key = u3nc(u3a_to_off(a), u3a_to_off(b));
+              u3_noun got = u3h_get(har_p, key);
+              u3z(key);
+              if ( u3_none != got ) {
+                _eq_pop();
+                continue;
+              }
+            }
+            _eq_push(a_u->hed, b_u->hed);
+            fam->sat_y = 1;
+            continue;
+          }
+        }
+        default:
+          c3_assert(0);
+      }
+    }
+
+    if ( c3n == r_o ) {
+      if ( 0 != har_p ) {
+        u3h_free(har_p);
+      }
+      u3R->cap_p = empty;
       return c3n;
     }
     else {
-          if ( c3n == _sing_x(u3a_h(a), u3a_h(b)) ) {
+      if ( 0 == har_p && (wis_w++ > EQ_WHISTLE) ) {
-            return c3n;
+        har_p = u3h_new();
       }
-          else if ( c3n == _sing_x(u3a_t(a), u3a_t(b)) ) {
+      if ( 0 != har_p ) {
-            return c3n;
+        u3_noun key = u3nc(u3a_to_off(a), u3a_to_off(b));
+        u3h_put(har_p, key, c3y);
+        u3z(key);
+      }
+      _eq_pop();
+    }
+  }
+
+  if ( 0 != har_p ) {
+    u3h_free(har_p);
   }
   return c3y;
 }
-      }
-    }
-  }
-}
 
 /* u3r_sang(): yes iff (a) and (b) are the same noun, unifying equals.
 */
 c3_o
 u3r_sang(u3_noun a, u3_noun b)
 {
-  return _sang_x(a, b);
+  return _song_x(a, b, &_sang_one);
 }
 
 /* u3r_sing():
@@ -863,7 +792,7 @@ u3r_sing(u3_noun a, u3_noun b)
     c3_o ret_o;
 
     u3t_on(euq_o);
-    ret_o = _sing_x(a, b);
+    ret_o = _song_x(a, b, &_sing_one);
     u3t_off(euq_o);
 
     return ret_o;
@@ -875,7 +804,7 @@ u3r_sing(u3_noun a, u3_noun b)
 c3_o
 u3r_sung(u3_noun a, u3_noun b)
 {
-  return _sung_x(a, b);
+  return _song_x(a, b, &_sung_one);
 }
 
 c3_o