Reduce random casting in looks_like_valid_lisp_pointer_p().

[sbcl.git] / src / runtime / x86-64-assem.S

diff --git a/src/runtime/x86-64-assem.S b/src/runtime/x86-64-assem.S
index 388c3bf..c4f5435 100644 (file)
--- a/src/runtime/x86-64-assem.S
+++ b/src/runtime/x86-64-assem.S
@@ -194,7 +194,7 @@ Lstack:
        xor     %rdx,%rdx       # clear any descriptor registers 
        xor     %rdi,%rdi       # that we can't be sure we'll 
        xor     %rsi,%rsi       # initialise properly.  XX do r8-r15 too?
-       shl     $3,%rcx         # (fixnumize num-args)
+       shl     $(N_FIXNUM_TAG_BITS),%rcx       # (fixnumize num-args)
        cmp     $0,%rcx
        je      Ldone
        mov     0(%rbx),%rdx    # arg0
@@ -266,6 +266,7 @@ GNAME(fpu_restore):
        .globl  GNAME(undefined_tramp)
        TYPE(GNAME(undefined_tramp))
 GNAME(undefined_tramp):
+       pop     8(%rbp)         # Save return PC for backtrace.
        TRAP
        .byte   trap_Error
         .byte   2
@@ -343,6 +344,12 @@ GNAME(closure_tramp):
 /*
  * fun-end breakpoint magic
  */
+
+/*
+ * For an explanation of the magic involved in function-end
+ * breakpoints, see the implementation in ppc-assem.S.
+ */
+
        .text
        .globl  GNAME(fun_end_breakpoint_guts)
        .align  align_16byte