First commit

1 files changed, 119 insertions, 0 deletions

diff --git a/src/routines/arithm.c b/src/routines/arithm.c
new file mode 100644
index 0000000..6ab4799
--- /dev/null
+++ b/src/routines/arithm.c
@@ -0,0 +1,119 @@
+/*
+ * nanowasm, a tiny WebAssembly/Wasm interpreter
+ * Copyright (C) 2023-2025  Xavier Del Campo Romero
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#include <nanowasm/nw.h>
+#include <nw/io.h>
+#include <nw/interp.h>
+#include <nw/log.h>
+#include <nw/routines.h>
+#include <nw/stack.h>
+#include <nw/types.h>
+
+static enum nw_state push(struct nw_interp *const i)
+{
+    struct nw_i_sm_arithm *const s = &i->sm.arithm;
+    const enum nw_state n = nwp_stack_push(i, &s->io);
+
+    if (n)
+        return n;
+
+    i->push_type = s->type;
+    nwp_interp_resume(i);
+    return NW_AGAIN;
+}
+
+static int init_io(struct nw_interp *const i)
+{
+    struct nw_i_sm_arithm *const s = &i->sm.arithm;
+    size_t sz;
+
+    if (nwp_type_sz(s->type, &sz))
+    {
+        static const char *const exc = "invalid operand type";
+
+        i->exception = exc;
+#ifdef NW_LOG
+        nwp_log("%s: %#x\n", exc, (unsigned)s->type);
+#endif
+        return -1;
+    }
+    else
+    {
+        struct nw_sm_io io = {0};
+
+        io.buf = &s->value;
+        io.n = sz;
+        s->io = io;
+    }
+
+    return 0;
+}
+
+static enum nw_state pop_left(struct nw_interp *const i)
+{
+    struct nw_i_sm_arithm *const s = &i->sm.arithm;
+    const enum nw_state n = nwp_stack_pop(i, &s->io);
+
+    if (n)
+        return n;
+
+    s->out.left = s->value;
+
+    if (s->op(&s->out, &s->value))
+    {
+        static const char *const exc = "arithmetic operation failed";
+
+        i->exception = exc;
+#ifdef NW_LOG
+        nwp_log("%s\n", exc);
+#endif
+        return NW_FATAL;
+    }
+    else if (init_io(i))
+        return NW_FATAL;
+
+    i->next = push;
+    return NW_AGAIN;
+}
+
+static enum nw_state pop_right(struct nw_interp *const i)
+{
+    struct nw_i_sm_arithm *const s = &i->sm.arithm;
+    const enum nw_state n = nwp_stack_pop(i, &s->io);
+
+    if (n)
+        return n;
+    else if (init_io(i))
+        return NW_FATAL;
+
+    s->out.right = s->value;
+    i->next = pop_left;
+    return NW_AGAIN;
+}
+
+static enum nw_state prepare_right(struct nw_interp *const i)
+{
+    if (init_io(i))
+        return NW_FATAL;
+
+    i->next = pop_right;
+    return NW_AGAIN;
+}
+
+void nwp_arithm(struct nw_interp *const i, const enum nw_type t,
+    int (*const op)(const struct nw_i_sm_arithm_out *, union nw_value *))
+{
+    const struct nw_i_sm_arithm s = {0};
+    struct nw_i_sm_arithm *const ps = &i->sm.arithm;
+
+    *ps = s;
+    ps->type = t;
+    ps->op = op;
+    i->next = prepare_right;
+}