Merge pull request #17 from tijko/Assembly

Assembly Solution #3

ASM/asm_solutions_1-10/Euler_3.S

@@ -0,0 +1,64 @@
+.section .data
+    answer: .asciz "Answer: %d\n"
+    anslen: .word 12
+
+.section .text
+    .globl main
+
+    # Layout:
+    #   r8  -> BigInt
+    #   r9  -> Start of Canidates
+    #   r10 -> Half of Current-Canidate
+    #   r11 -> Range (2..r10/2)
+    main:
+        pushq   %rbp
+        movq    %rsp, %rbp
+        xor     %rdx, %rdx
+        jmp     setup
+
+    setup:
+        xor       %r8,           %r8
+        movq      $600851475143, %r8
+        cvtsi2sdq %r8,           %xmm0
+        sqrtsd    %xmm0,         %xmm0
+        cvttsd2si %xmm0,         %r9
+        jmp       next
+
+    next:
+        dec       %r9
+        movq      %r9,           %rax
+        cvtsi2sdq %r9,           %xmm1
+        sqrtsd    %xmm1,         %xmm1
+        cvttsd2si %xmm1,         %r10
+        movq      $2,            %r11
+        movq      %r9,           %rax
+        jmp       factor
+
+    factor:
+        xor     %rdx, %rdx
+        div     %r11
+        test    %rdx, %rdx
+        jz      next 
+        cmp     %r11, %r10
+        je      prime
+        inc     %r11
+        movq    %r9, %rax
+        xor     %rdx, %rdx
+        jmp     factor
+
+    prime:
+        movq    %r8,  %rax
+        xor     %rdx, %rdx
+        div     %r9
+        test    %rdx, %rdx
+        jz      exit
+        jmp     next 
+
+    exit:
+        leaq    answer(%rip), %rdi
+        movq    %r9,          %rsi
+        callq   printf
+
+        movq    $60, %rax
+        movq    $1,  %rdi
+        syscall

ASM/asm_solutions_1-10/Makefile

@@ -3,10 +3,10 @@ LFLAGS := -static -lc
 CFLAGS := -c -g -fverbose-asm
 
 default:
-	$(CC) $(CFLAGS) Euler_2.S
+	$(CC) $(CFLAGS) Euler_3.S
 
 link:
-	$(CC) $(LFLAGS) Euler_2.o -o Euler_2
+	$(CC) $(LFLAGS) Euler_3.o -o Euler_3
 
 clean:
-	rm Euler_2.o Euler_2
+	rm Euler_3.o Euler_3