Code refactoring of Emscripten platform support (single-threaded)

* alloc.c (min_bytes_allocd): Test STACK_NOT_SCANNED macro instead
of __EMSCRIPTEN__ (stack size to scan is zero if STACK_NOT_SCANNED).
* include/private/gcconfig.h (ALIGNMENT): Remove duplicate definition
for _EMSCRIPTEN__.
* include/private/gcconfig.h (STACK_NOT_SCANNED): New macro defined
for __EMSCRIPTEN__ target (in addition to  OS_TYPE, CPP_WORDSZ,
ALIGNMENT, DATASTART, DATAEND).
* mach_dep.c (GC_push_regs): Test STACK_NOT_SCANNED macro instead
of __EMSCRIPTEN__ (push nothing if STACK_NOT_SCANNED).
* mark_rts.c (GC_push_roots): Test STACK_NOT_SCANNED macro instead
of __EMSCRIPTEN__ (do not call GC_push_regs_and_stack if
STACK_NOT_SCANNED); mark cold_gc_frame argument as potentially unused.
* misc.c (GC_clear_stack): Test STACK_NOT_SCANNED macro instead
of __EMSCRIPTEN__ (do not clear stack if STACK_NOT_SCANNED).
* misc.c (GC_clear_stack): Reformat code.

1 files changed, 4 insertions, 4 deletions

diff --git a/mark_rts.c b/mark_rts.c
index 53341586..fc1f46c3 100644
--- a/mark_rts.c
+++ b/mark_rts.c
@@ -751,7 +751,7 @@ STATIC void GC_push_regs_and_stack(ptr_t cold_gc_frame)
  * A zero value indicates that it's OK to miss some
  * register values.
  */
-GC_INNER void GC_push_roots(GC_bool all, ptr_t cold_gc_frame)
+GC_INNER void GC_push_roots(GC_bool all, ptr_t cold_gc_frame GC_ATTR_UNUSED)
 {
     int i;
     unsigned kind;
@@ -810,9 +810,9 @@ GC_INNER void GC_push_roots(GC_bool all, ptr_t cold_gc_frame)
      * This is usually done by saving the current context on the
      * stack, and then just tracing from the stack.
      */
-#ifndef __EMSCRIPTEN__
-      GC_push_regs_and_stack(cold_gc_frame);
-#endif
+#    ifndef STACK_NOT_SCANNED
+       GC_push_regs_and_stack(cold_gc_frame);
+#    endif
 
     if (GC_push_other_roots != 0) (*GC_push_other_roots)();
         /* In the threads case, this also pushes thread stacks. */