1 files changed, 119 insertions, 0 deletions
diff --git a/ir/fold.c b/ir/fold.c
new file mode 100644
index 0000000..fd6076e
--- /dev/null
+++ b/ir/fold.c
@@ -0,0 +1,119 @@
+#include "ir.h"
+
+static union ref
+foldint(enum op op, enum irclass k, union ref lr, union ref rr)
+{
+   vlong x;
+   union {
+      vlong s;
+      uvlong u;
+   } l = {.s = intconval(lr)}, r = {.s = intconval(rr)};
+   bool w = cls2siz[k] == 8;
+   if (in_range(op, Odiv, Ourem)) assert(r.u != 0);
+   switch (op) {
+   case Ocopy: x = l.s; break;
+   case Oneg:  x = -l.s; break;
+   case Onot:  x = ~l.s; break;
+   case Ocvtf4s: x = (int)(float)fltconval(lr); break;
+   case Ocvtf4u: x = (uint)(float)fltconval(lr); break;
+   case Ocvtf8s: x = (vlong)fltconval(lr); break;
+   case Ocvtf8u: x = (uvlong)fltconval(lr); break;
+   case Oexts1: x = (schar)l.s; break;
+   case Oextu1: x = (uchar)l.s; break;
+   case Oexts2: x = (short)l.s; break;
+   case Oextu2: x = (ushort)l.s; break;
+   case Oexts4: x = (int)l.s; break;
+   case Oextu4: x = (uint)l.s; break;
+   case Oadd:  x = l.u + r.u; break;
+   case Osub:  x = l.u - r.u; break;
+   case Omul:  x = l.u * r.u; break;
+   case Oumul: x = l.u * r.u; break;
+   case Odiv:  x = w ? l.s / r.s : (int)l.s / (int)r.s; break;
+   case Oudiv: x = w ? l.u / r.u : (uint)l.u / (uint)r.u; break;
+   case Orem:  x = w ? l.s % r.s : (int)l.s % (int)r.s; break;
+   case Ourem: x = w ? l.u % r.u : (uint)l.u % (uint)r.u; break;
+   case Oand:  x = l.u & r.u; break;
+   case Oior:  x = l.u | r.u; break;
+   case Oxor:  x = l.u ^ r.u; break;
+   case Oshl:  x = l.u << (r.u & (w ? 63 : 31)); break;
+   case Oslr:  x = w ? l.u >> (r.u&63) : (int)l.s >> (r.u&31); break;
+   case Osar:  x = w ? l.s >> (r.u&63) : (int)l.s >> (r.u&31); break;
+   case Oequ:  x = l.s == r.s; break;
+   case Oneq:  x = l.s != r.s; break;
+   case Olth:  x = l.s < r.s; break;
+   case Ogth:  x = l.s > r.s; break;
+   case Olte:  x = l.s <= r.s; break;
+   case Ogte:  x = l.s >= r.s; break;
+   case Oulth: x = l.u < r.u; break;
+   case Ougth: x = l.u > r.u; break;
+   case Oulte: x = l.u <= r.u; break;
+   case Ougte: x = l.u >= r.u; break;
+   default: assert(0);
+   }
+   return mkintcon(k, x);
+}
+
+static union ref
+foldflt(enum op op, enum irclass k, union ref lr, union ref rr)
+{
+   int xi;
+   double x, l = fltconval(lr), r = fltconval(rr);
+   bool w = k == KF8;
+   if (in_range(op, Odiv, Ourem)) assert(r != 0.0);
+   switch (op) {
+   case Ocopy: x = l; break;
+   case Oneg:  x = -l; break;
+   case Ocvtf4f8: x = (float)l; break;
+   case Ocvtf8f4: x = (float)l; break;
+   case Ocvts4f:  x = (int)intconval(lr); break;
+   case Ocvtu4f:  x = (int)intconval(lr); break;
+   case Ocvts8f:  x = (vlong)intconval(lr); break;
+   case Ocvtu8f:  x = (uvlong)intconval(lr); break;
+   case Oadd: x = l + r; break;
+   case Osub: x = l - r; break;
+   case Omul: x = l * r; break;
+   case Odiv: x = l / r; break;
+   case Oequ: xi = l == r; break;
+   case Oneq: xi = l != r; break;
+   case Olth: xi = l < r; break;
+   case Ogth: xi = l > r; break;
+   case Olte: xi = l <= r; break;
+   case Ogte: xi = l >= r; break;
+   default: assert(0);
+   }
+   if (oiscmp(op)) return mkref(RICON, xi);
+   if (!w) x = (float)x;
+   return mkfltcon(k, x);
+}
+
+bool
+foldbinop(union ref *to, enum op op, enum irclass k, union ref l, union ref r)
+{
+   if (!iscon(l) || !iscon(r)) return 0;
+   if (in_range(op, Odiv, Ourem) && (kisint(k) ? intconval(r) == 0 : fltconval(r) == 0))
+      return 0;
+   if (!oisarith(op))
+      return 0;
+   to->t = oiscmp(op) ? KI4 : k;
+   if (kisint(k))
+      *to = foldint(op, k, l, r);
+   else
+      *to = foldflt(op, k, l, r);
+   return 1;
+}
+
+bool
+foldunop(union ref *to, enum op op, enum irclass k, union ref a)
+{
+   if (!iscon(a)) return 0;
+   if (op != Ocopy && !oisarith(op))
+      return 0;
+   to->t = k;
+   if (kisint(k))
+      *to = foldint(op, k, a, ZEROREF);
+   else
+      *to = foldflt(op, k, a, ZEROREF);
+   return 1;
+}
+
+/* vim:set ts=3 sw=3 expandtab: */