int arch_os_thread_init(struct thread *thread) {
{
- //unsigned long cur_stack_base;
- //unsigned long cur_stack_end;
+ void *top_exception_frame;
void *cur_stack_end;
-
- //asm volatile ("movl %%fs:8,%0": "=r" (cur_stack_base));
- // asm volatile ("movl %%fs:4,%0": "=r" (cur_stack_end));
-
- asm volatile ("movl %%fs:0,%0": "=r" (cur_stack_end));
-
- // fprintf(stderr, "#x%08lx #x%08lx.\n", cur_stack_base, cur_stack_end);
-
- //if (cur_stack_base > thread->control_stack_start) {
- // cur_stack_base = thread->control_stack_start;
- //}
-
- //if (cur_stack_end < thread->control_stack_end) {
- // cur_stack_end = thread->control_stack_end;
- //}
-
- // fprintf(stderr, "#x%08lx #x%08lx.\n", cur_stack_base, cur_stack_end);
- //fflush(stderr);
-
- //getchar();
-
- //asm volatile ("movl %0,%%fs:8": : "r" (cur_stack_base));
- //asm volatile ("movl %0,%%fs:4": : "r" (cur_stack_end));
-
- thread->control_stack_end = cur_stack_end;
+ void *cur_stack_start;
+
+ asm volatile ("movl %%fs:0,%0": "=r" (top_exception_frame));
+ asm volatile ("movl %%fs:4,%0": "=r" (cur_stack_end));
+
+ /*
+ * Can't pull stack start from fs:4 or fs:8 or whatever,
+ * because that's only what currently has memory behind
+ * it from being used. Our basic options are to know,
+ * a priori, what the stack size is (1 meg by default)
+ * or to grub the default size out of the executable
+ * header in memory by means of hardcoded addresses and
+ * offsets.
+ *
+ * We'll just assume it's 1 megabyte. Easiest that way.
+ */
+ cur_stack_start = cur_stack_end - 0x100000;
+
+ /*
+ * We use top_exception_frame rather than cur_stack_end
+ * to elide the last few (boring) stack entries at the
+ * bottom of the backtrace.
+ */
+ thread->control_stack_start = cur_stack_start;
+ thread->control_stack_end = top_exception_frame;
+
+#ifndef LISP_FEATURE_SB_THREAD
+ /*
+ * Theoretically, threaded SBCL binds directly against
+ * the thread structure for these values. We don't do
+ * threads yet, but we'll probably do the same. We do
+ * need to reset these, though, because they were
+ * initialized based on the wrong stack space.
+ */
+ SetSymbolValue(CONTROL_STACK_START,(lispobj)thread->control_stack_start,thread);
+ SetSymbolValue(CONTROL_STACK_END,(lispobj)thread->control_stack_end,thread);
+#endif
}
#ifdef LISP_FEATURE_SB_THREAD