nixify

2026-06-11 10:59:54 -06:00
commit 8650a71f67
159 changed files with 78653 additions and 0 deletions
@@ -0,0 +1,124 @@
+#include "all.h"
+
+static void
+blit(Ref sd[2], int sz, Fn *fn)
+{
+	struct { int st, ld, cls, size; } *p, tbl[] = {
+		{ Ostorel, Oload,   Kl, 8 },
+		{ Ostorew, Oload,   Kw, 4 },
+		{ Ostoreh, Oloaduh, Kw, 2 },
+		{ Ostoreb, Oloadub, Kw, 1 }
+	};
+	Ref r, r1, ro;
+	int off, fwd, n;
+
+	fwd = sz >= 0;
+	sz = abs(sz);
+	off = fwd ? sz : 0;
+	for (p=tbl; sz; p++)
+		for (n=p->size; sz>=n; sz-=n) {
+			off -= fwd ? n : 0;
+			r = newtmp("blt", Kl, fn);
+			r1 = newtmp("blt", Kl, fn);
+			ro = getcon(off, fn);
+			emit(p->st, 0, R, r, r1);
+			emit(Oadd, Kl, r1, sd[1], ro);
+			r1 = newtmp("blt", Kl, fn);
+			emit(p->ld, p->cls, r, r1, R);
+			emit(Oadd, Kl, r1, sd[0], ro);
+			off += fwd ? 0 : n;
+		}
+}
+
+static int
+ulog2_tab64[64] = {
+	63,  0,  1, 41, 37,  2, 16, 42,
+	38, 29, 32,  3, 12, 17, 43, 55,
+	39, 35, 30, 53, 33, 21,  4, 23,
+	13,  9, 18,  6, 25, 44, 48, 56,
+	62, 40, 36, 15, 28, 31, 11, 54,
+	34, 52, 20, 22,  8,  5, 24, 47,
+	61, 14, 27, 10, 51, 19,  7, 46,
+	60, 26, 50, 45, 59, 49, 58, 57,
+};
+
+static int
+ulog2(uint64_t pow2)
+{
+	return ulog2_tab64[(pow2 * 0x5b31ab928877a7e) >> 58];
+}
+
+static int
+ispow2(uint64_t v)
+{
+	return v && (v & (v - 1)) == 0;
+}
+
+static void
+ins(Ins **pi, int *new, Blk *b, Fn *fn)
+{
+	ulong ni;
+	Con *c;
+	Ins *i;
+	Ref r;
+	int n;
+
+	i = *pi;
+	/* simplify more instructions here;
+	 * copy 0 into xor, bit rotations,
+	 * etc. */
+	switch (i->op) {
+	case Oblit1:
+		assert(i > b->ins);
+		assert((i-1)->op == Oblit0);
+		if (!*new) {
+			curi = &insb[NIns];
+			ni = &b->ins[b->nins] - (i+1);
+			curi -= ni;
+			icpy(curi, i+1, ni);
+			*new = 1;
+		}
+		blit((i-1)->arg, rsval(i->arg[0]), fn);
+		*pi = i-1;
+		return;
+	case Oudiv:
+	case Ourem:
+		r = i->arg[1];
+		if (KBASE(i->cls) == 0)
+		if (rtype(r) == RCon) {
+			c = &fn->con[r.val];
+			if (c->type == CBits)
+			if (ispow2(c->bits.i)) {
+				n = ulog2(c->bits.i);
+				if (i->op == Ourem) {
+					i->op = Oand;
+					i->arg[1] = getcon((1ull<<n) - 1, fn);
+				} else {
+					i->op = Oshr;
+					i->arg[1] = getcon(n, fn);
+				}
+			}
+		}
+		break;
+	}
+	if (*new)
+		emiti(*i);
+}
+
+void
+simpl(Fn *fn)
+{
+	Blk *b;
+	Ins *i;
+	int new;
+
+	for (b=fn->start; b; b=b->link) {
+		new = 0;
+		for (i=&b->ins[b->nins]; i!=b->ins;) {
+			--i;
+			ins(&i, &new, b, fn);
+		}
+		if (new)
+			idup(b, curi, &insb[NIns]-curi);
+	}
+}