regalloc: start implementing linear scan

4 files changed, 71 insertions, 1 deletions

diff --git a/test/collatz.c b/test/collatz.c
new file mode 100644
index 0000000..9793594
--- /dev/null
+++ b/test/collatz.c
@@ -0,0 +1,29 @@
+int printf(const char *, ...);
+void *malloc(unsigned long);
+int main() {
+   int *mem = malloc(sizeof(int) * 4000);
+
+   int cmax = 0;
+   for (int nv = 1; nv < 1000; ++nv) {
+      int n = nv, c = 0;
+      while (n != 1) {
+         if (n < nv) {
+            c += mem[n];
+            break;
+         }
+         if ((n & 1) != 0) {
+            n = (3 * n) + 1;
+         } else {
+            n /= 2;
+            //n >>= 1;
+         }
+         ++c;
+      }
+      mem[nv] = c;
+      if (c > cmax) {
+         cmax = c;
+      }
+   }
+   printf("should print 178: %d\n", cmax);
+}
+
diff --git a/test/fact.c b/test/fact.c
new file mode 100644
index 0000000..1147d8f
--- /dev/null
+++ b/test/fact.c
@@ -0,0 +1,13 @@
+int
+fact(int x)
+{
+   int y = 1;
+   while (x >= 1) {
+      y *= x;
+      x -= 1;
+   }
+   return y;
+}
+
+extern int printf();
+int main() { printf("6! = %d\n", fact(6)); }
diff --git a/test/fib.c b/test/fib.c
index 5fe430a..0c02171 100644
--- a/test/fib.c
+++ b/test/fib.c
@@ -29,8 +29,8 @@ int printf(const char *, ...);
 int main(int argc, char **argv) {
    unsigned n = argv[1] ? atoi(argv[1]) : 10;
    printf("fib(%u)  = %u\n", n, fib(n));
-   printf("fibr(%u) = %u\n", n, fibr(n));
    printf("fibf(%u) = %g\n", n, fibf(n));
+   printf("fibr(%u) = %u\n", n, fibr(n));
 }
 
 /* vim:set ts=3 sw=3 expandtab: */
diff --git a/test/sort.c b/test/sort.c
new file mode 100644
index 0000000..af58917
--- /dev/null
+++ b/test/sort.c
@@ -0,0 +1,28 @@
+typedef unsigned long size_t;
+
+int printf(const char *, ...);
+void *calloc(size_t, size_t);
+void qsort(void *, size_t nmemb, size_t size, int (const void *, const void *));
+int atoi(const char *);
+
+int
+icmp(const void *a, const void *b)
+{
+   int l = *(int *)a, r = *(int *)b;
+   return (l > r) - (l < r);
+}
+
+int
+main(int argc, char **argv)
+{
+   int N = argc - 1;
+   int *xs = calloc(N, sizeof *xs);
+
+   for (int i = 0; i < N; ++i)
+      xs[i] = atoi(argv[i+1]);
+   qsort(xs, N, sizeof *xs, icmp);
+   for (int i = 0; i < N; ++i)
+      printf("%d, ", xs[i]);
+   printf("\n");
+   return N;
+}