bbonev squeeze

diff --git a/asm/reaper.asm b/asm/reaper.asm
index 0086a8f7ee23ad0b1c1ce032f8bb0eabdec7ef4c..c5dee499dcfa23e3f203a7ba5d73f882e0fda68d 100644 (file)
--- a/asm/reaper.asm
+++ b/asm/reaper.asm
@@ -6,41 +6,32 @@
        format elf64 executable
        entry main
 
-       ;; A data segment
-       segment readable writable
+;;; Using mixed Data and Code segment for size squeeze
 
-       ;; sigset_t set -- bit mask for sigprocmask
-set:   dq -1   ; all bits set
-       
-;;; siginfo_t status -- all ignored
-status:        rept 16 { dq 0 }
-status$end:
-       
-;;; A code segment
-       segment readable executable
+       segment readable writable executable
        
 ;;; Main entry point
 main:
        ;; if (getpid() != 1) exit 1;
-       mov rax, qword 39
+       xor rax, rax
+       mov al, 39
+       ; rax=39
        syscall
-       cmp rax, 1
-       je pid_1
-       
-       ;; exit(1)
-       mov rdi, qword 1
-       mov rax, qword 60
-        syscall                ; exit program
+
+       dec rax
+       jnz exit        ; exit(1)
 
        ;; Continue here for pid 1 only
 pid_1:
        ;; Block all signals
        ;; sigprocmask(SIG_BLOCK, &set, 0);
-       xor rdi, rdi            ; SIG_BLOCK = 0
+       ; rax is already 0
+       mov rdi, rax            ; SIG_BLOCK = 0
        lea rsi, [set]          ; *set
-       xor rdx, rdx            ; 0
-       xor r10, r10            ; 0
-       mov rax, qword 14       ; sys_rt_sigprocmask
+       mov rdx, rax            ; 0
+       mov r10, rax            ; 0
+       mov al, 14                      ; sys_rt_sigprocmask
+       ; rax=14, rdi=0, rsi=[set], rdx=0, r10=0
        syscall
 
        ;; loop waiting for children, and reading their exit status
@@ -48,26 +39,37 @@ reaper:
        ;; first clear status area again
        cld
        xor rax, rax
-       lea rsi, [status$end]
        lea rdi, [status]
-clear: stosq
-       cmp rdi,rsi
-       jl clear
+       mov rdx, rdi
+       mov rcx, rax
+       mov cl, status$end-status
+       rep stosq
        
        ;; waitid( idtype, id, *status, options )
-       xor rdi, rdi      ;  idtype_t idtype = P_ALL = 0
-       xor rsi, rsi      ; int id = 0
-       lea rdx, [status] ; siginfo_t* = &status
-       mov r10, 4        ; int options = WEXITED = 4
-       mov rax, 247      ; waitid
+       mov rdi, rax            ; idtype_t idtype = P_ALL = 0
+       mov rsi, rax            ; int id = 0
+       ;rdx = [status]         ; siginfo_t* = &status
+       mov al, 4                       ; int options = WEXITED = 4
+       mov r10, rax
+       mov al, 247                     ; waitid
+       ; rax=247, rdi=0, rsi=0, rdx=[status], r10=4
        syscall
 
-       cmp rax,-10       ; -10 = ECHILD (no child processes)
-       jne reaper
-
+       add rax, 10 ; -10 = ECHILD (no child processes)
+       jnz reaper
+       
+exit:  ; exit(1)
+       xor rax, rax
        mov rdi, rax
-       mov rax, qword 60
-        syscall        ; exit program
+       inc rdi
+       mov al, 60
+       syscall         ; exit(1) program
 
-;;; The rest of memory is not executable
-       segment readable writable
+       ;; sigset_t set -- bit mask for sigprocmask
+set:
+       dq -1   ; all bits set
+       
+;;; siginfo_t status -- all ignored
+status:
+       rept 16 { dq ? }
+status$end: