1 files changed, 115 insertions, 0 deletions
diff --git a/wasm/tests/machine_test.c b/wasm/tests/machine_test.c
new file mode 100644
index 0000000000..f4b62ff580
--- /dev/null
+++ b/wasm/tests/machine_test.c
@@ -0,0 +1,115 @@
+#include <stdio.h>
+#include <assert.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include "wasm/machine.h"
+#include "wasm/asyncify.h"
+
+void *rb_wasm_get_stack_pointer(void);
+
+static void *base_stack_pointer = NULL;
+
+int __attribute__((constructor)) record_base_sp(void) {
+  base_stack_pointer = rb_wasm_get_stack_pointer();
+  return 0;
+}
+
+void dump_memory(uint8_t *base, uint8_t *end) {
+  size_t chunk_size = 16;
+
+  for (uint8_t *ptr = base; ptr <= end; ptr += chunk_size) {
+    printf("%p", ptr);
+    for (size_t offset = 0; offset < chunk_size; offset++) {
+      printf(" %02x", *(ptr + offset));
+    }
+    printf("\n");
+  }
+}
+
+bool find_in_stack(uint32_t target, void *base, void *end) {
+  for (uint32_t *ptr = base; ptr <= (uint32_t *)end; ptr++) {
+    if (*ptr == target) {
+      return true;
+    }
+  }
+  return false;
+}
+
+void *_rb_wasm_stack_mem[2];
+void rb_wasm_mark_mem_range(void *start, void *end) {
+  _rb_wasm_stack_mem[0] = start;
+  _rb_wasm_stack_mem[1] = end;
+}
+
+#define check_live(target, ctx) do {            \
+    rb_wasm_scan_stack(rb_wasm_mark_mem_range); \
+    _check_live(target, ctx);                   \
+  } while (0);
+
+void _check_live(uint32_t target, const char *ctx) {
+  printf("checking %#x ... ", target);
+  bool found_in_locals = false, found_in_stack = false;
+  if (find_in_stack(target, _rb_wasm_stack_mem[0], _rb_wasm_stack_mem[1])) {
+    found_in_stack = true;
+  }
+  rb_wasm_scan_locals(rb_wasm_mark_mem_range);
+  if (find_in_stack(target, _rb_wasm_stack_mem[0], _rb_wasm_stack_mem[1])) {
+    found_in_locals = true;
+  }
+  if (found_in_locals && found_in_stack) {
+    printf("ok (found in C stack and Wasm locals)\n");
+  } else if (found_in_stack) {
+    printf("ok (found in C stack)\n");
+  } else if (found_in_locals) {
+    printf("ok (found in Wasm locals)\n");
+  } else {
+    printf("not found: %s\n", ctx);
+    assert(false);
+  }
+}
+
+void new_frame(uint32_t val, uint32_t depth) {
+  if (depth == 0) {
+    dump_memory(rb_wasm_get_stack_pointer(), base_stack_pointer);
+    for (uint32_t i = 0; i < 5; i++) {
+      check_live(0x00bab10c + i, "argument value");
+    }
+  } else {
+    new_frame(val, depth - 1);
+  }
+}
+
+uint32_t return_value(void) {
+  return 0xabadbabe;
+}
+
+uint32_t check_return_value(void) {
+  check_live(0xabadbabe, "returned value");
+  return 0;
+}
+
+void take_two_args(uint32_t a, uint32_t b) {
+}
+
+__attribute__((noinline))
+int start(int argc, char **argv) {
+
+  uint32_t deadbeef;
+  register uint32_t facefeed;
+  deadbeef = 0xdeadbeef;
+  facefeed = 0xfacefeed;
+
+  check_live(0xdeadbeef, "local variable");
+  check_live(0xfacefeed, "local reg variable");
+
+  new_frame(0x00bab10c, 5);
+
+  take_two_args(return_value(), check_return_value());
+
+  return 0;
+}
+
+int main(int argc, char **argv) {
+  extern int rb_wasm_rt_start(int (main)(int argc, char **argv), int argc, char **argv);
+  return rb_wasm_rt_start(start, argc, argv);
+}