it works a bit

This commit is contained in:
Christoph J. Scherr 2023-12-10 15:06:42 +01:00
parent 84812d7664
commit 73e402bcb7
2 changed files with 51 additions and 0 deletions

BIN
bin/Factorial.class Normal file

Binary file not shown.

51
src/Factorial.jas Normal file
View File

@ -0,0 +1,51 @@
.class public Factorial
.super java/lang/Object
.method public <init>()V
aload 0
invokenonvirtual java/lang/Object/<init>()V
return
.end method
.method public static factorial(I)I ; calc `given`!
.limit locals 3
.limit stack 5
bipush 1 ;
istore 0 ; store the parameter `given`
bipush 1 ; we start calculating with `p`=1
istore 1 ; store `p`
bipush 2 ; we start calculating with `j`=1
istore 2 ; store `j`
loop:
; p *= j
iload 1 ; load p
iload 2 ; load j
imul ; multiply p and j
istore 1 ; store p*j in p
; j++
iload 2 ; load j
bipush 1 ; put a 1 on the stack
iadd ; add j and 1
istore 2 ; store j+1 in j
; if j<given
iload 2 ; load j
iload 0 ; load given
if_icmplt loop ; if j < given goto loop
; else return given * p
iload 0 ; load given
iload 1 ; load p
imul ; multiply given and p
ireturn ; return given*p
.end method
.method public static main([Ljava/lang/String;)V
.limit locals 1
.limit stack 3
getstatic java/lang/System/out Ljava/io/PrintStream;
invokevirtual java/io/PrintStream/println(Ljava/lang/String;)V
return
.end method