Re: An execution time puzzle

Brett <ggtgp@yahoo.com> writes:

Anton Ertl <anton@mips.complang.tuwien.ac.at> wrote:

anton@mips.complang.tuwien.ac.at (Anton Ertl) writes:
I recreated this in assembly language:
 
        .text
        .globl main
main:
        mov $threaded, %rdx
        mov $0, %rbx
        mov $(returnstack+8),%r13
        mov %rdx, %r8
docol:  
        add    $0x8,%rbx
        sub    $0x8,%r13
        mov    %rbx,0x0(%r13)
        mov    %rdx,%rbx
        mov    (%rbx),%rax
        jmp    *%rax
outout:
        mov    %r8,%r15
        add    $0x10,%rbx
        mov    0x0(%r13),%rbx
        mov    -0x10(%r15),%rax
        mov    %r15,%rdx
        add    $0x8,%r13
        sub    $0x8,%rbx
        jmp    *%rax
 
        .data
        .quad docol
        .quad 0
threaded:
        .quad outout
returnstack:
        .zero 16,0

...

How about giving us the original source code function, my x86 is rusty and
it is helpful to plug source into compiler explorer to see what different
compilers do.

The original source code is

: foo dup execute-exit ;
\ invoked with
' foo foo

This is Forth source code for Gforth (and the output is from
gforth-fast).  I expect that most c.a readers will find the assembly
language more approachable:-)

- anton
--
'Anyone trying for "industrial quality" ISA should avoid undefined behavior.'
  Mitch Alsup, <c17fcd89-f024-40e7-a594-88a85ac10d20o@googlegroups.com>