Added description. x86 solutions for some problemsHEADmaster

5 files changed, 50 insertions, 0 deletions

diff --git a/05-Smallest-Multiple/asm/Makefile b/05-Smallest-Multiple/asm/Makefile
new file mode 100644
index 0000000..3ae43fc
--- /dev/null
+++ b/05-Smallest-Multiple/asm/Makefile
@@ -0,0 +1,6 @@
+smallmult: smallmult.o
+	gcc smallmult.o -o smallmult 
+smallmult.o: smallmult.asm
+	nasm -w+all -f elf64 -g -F stabs smallmult.asm
+clean:
+	rm -f smallmult smallmult.o
diff --git a/05-Smallest-Multiple/asm/smallmult b/05-Smallest-Multiple/asm/smallmult
new file mode 100755
index 0000000..af65d5a
--- /dev/null
+++ b/05-Smallest-Multiple/asm/smallmult
diff --git a/05-Smallest-Multiple/asm/smallmult.asm b/05-Smallest-Multiple/asm/smallmult.asm
new file mode 100644
index 0000000..c154ff3
--- /dev/null
+++ b/05-Smallest-Multiple/asm/smallmult.asm
@@ -0,0 +1,44 @@
+; 2520 is the smallest number that can be divided by each of the numbers 
+; from 1 to 10 without any remainder.
+; What is the smallest positive number that is evenly divisible by all 
+; of the numbers from 1 to 20?
+
+extern printf
+SECTION .data
+flag:   db  "%d",10,0           ; "%d\n\0"
+
+SECTION .text
+    global main    
+    global is_divisible
+
+main:
+        push rbp                ; set up stack
+        mov rbp, rsp
+
+        mov rax, 2520           ; value to start at (given)
+        mov rcx, 20             ; divisor (counting down)
+.loop   add rax, rcx
+        push rcx
+.isdiv  xor rdx, rdx            ; clear rdx for div
+        push rax                ; save rax before dividing
+        div rcx                 ; rdx:rax/rcx = rax remainder rdx
+        pop rax                 ; reload rax to be divided again
+        cmp rdx, 0              ; the number was divisible, keep going
+        loopz .isdiv            ; loop exits if rdx is non zero OR rcx is 0
+        cmp rcx, 0              ; if rcx = 0, it means it looped 20 to 1 w/o
+        jz .print               ; any remainders, that's our number!
+        ; if you get here, number couldn't be evenly divided by all numbers
+        pop rcx
+        jmp .loop
+
+
+
+.print: mov rdi, flag           ; arg 1 (format)
+        mov rsi, rax            ; arg 2 (value)
+        mov rax, 0		; no xmm registers
+        call printf wrt ..plt
+        pop rbp
+
+        mov rax, 0
+        ret
+
diff --git a/05-Smallest-Multiple/asm/smallmult.o b/05-Smallest-Multiple/asm/smallmult.o
new file mode 100644
index 0000000..d2c9fe0
--- /dev/null
+++ b/05-Smallest-Multiple/asm/smallmult.o
diff --git a/05-Smallest-Multiple/smallmult b/05-Smallest-Multiple/smallmult
index 5f4e692..5f4e692 100644..100755
--- a/05-Smallest-Multiple/smallmult
+++ b/05-Smallest-Multiple/smallmult