Cool strategies

2 files changed, 46 insertions, 5 deletions

diff --git a/readme.md b/readme.md
index 6d096c0..2531502 100644
--- a/readme.md
+++ b/readme.md
@@ -1,8 +1,18 @@
 # Sleepsort
 
-> efficiently sleeping
+> efficiently sleeping with (sub-)nanosecond precision and asm threads
 
-## Installation
+## Dependencies
 
-    make
-    ./sort
+- ed
+- nasm
+- gcc
+- make
+
+## Usage
+
+``` bash
+ed sort.asm # edit array and choose coolsleep/boringsleep
+make
+./sort
+```
diff --git a/sort.asm b/sort.asm
index d089dc9..9b3569b 100644
--- a/sort.asm
+++ b/sort.asm
@@ -24,7 +24,36 @@ end:
 	mov     rdi, 0
 	syscall ; exit
 
+; this works sometimes (if numbers are good)
+; uses busy loop
+coolsleep:
+	mov     rax, 0x4242424
+	mov     rcx, rsi
+	mul     rcx
+.loop:
+	dec     rax
+	jnz     .loop
+	ret
+
+; this works on most normal CPUs (if numbers are good)
+; uses nanosleep syscall
+boringsleep:
+	mov     rax, 0x424242
+	mov     rcx, rsi
+	mul     rcx
+	push    qword rax ; ns
+	push    qword 0 ; s
+	mov     rax, 0x23
+	mov     rdi, rsp
+	xor     rsi, rsi
+	syscall
+	add     rsp, 16
+	ret
+
 print:
+	push    rsi
+	call    boringsleep ; or coolsleep
+	pop     rsi
 	mov     rdi, format
 	xor     rax, rax
 	call    printf
@@ -32,7 +61,7 @@ print:
 
 thread:
 	lea     rax, print
-	mov     rsi, [array + (ecx - 1) * 4]
+	mov     esi, [array + (ecx - 1) * 4]
 	call    thread_run
 	ret
 
@@ -58,6 +87,8 @@ child:
 
 ;;; data
 
+section .data
+
 array: dd 3,1,4,1,5,9,2,6,5,3,5,8,9,7,9,3
 size: equ ($-array)/4
 format: db "%d", 10, 0