x86 - intel and att syntax

risc-v/Makefile

@@ -1,4 +1,4 @@
 default:
 	rm -rf hello
-	riscv64-linux-gnu-as hello.s -o hello.o
-	riscv64-linux-gnu-gcc -o hello hello.s -nostdlib -static
+	riscv64-linux-gnu-as main.asm -o main.o
+	riscv64-linux-gnu-gcc -o main main.asm -nostdlib -static

risc-v/main.s

@@ -0,0 +1,18 @@
+.globl __start
+
+.data
+msg:
+	.string "Hello World!"
+	.byte 0
+.text
+
+__start:
+	LA a0, msg
+	li a7, 4 
+	ecall
+
+	j Shutdown
+
+Shutdown:
+	li a7, 10
+	ecall

x86/exit_project/exit.s

@@ -0,0 +1,10 @@
+.section .data
+
+.section .text
+
+.globl _start
+_start:
+	movl $1, %eax
+	movl $0, %ebx
+
+	int $0x80

x86/maximum/att/maximum.s

@@ -0,0 +1,38 @@
+# VARIABLES: The registers have the following uses:
+#
+# %edi - Holds the index of the data item being examined
+# %ebx - Largest data item found
+# %eax - Current data item 
+# 
+# The following memory locations are used:
+#
+# data_items - contains the item data. A 0 is used to terminate the data
+# 
+
+.section .data
+
+data_items:
+	.long 3, 67, 34, 222, 45, 75, 54, 34, 44, 33, 22, 11, 66, 0
+
+.section .text
+
+.globl _start
+_start: 
+	movl $0, %edi				
+	movl data_items(, %edi, 4), %eax
+	movl %eax, %ebx
+
+start_loop:
+	cmpl $0, %eax
+	je loop_exit
+	incl %edi
+	movl data_items(,%edi,4), %eax
+	cmpl %ebx, %eax
+	jle start_loop
+
+	movl %eax, %ebx
+	jmp start_loop
+
+loop_exit:
+	movl $1, %eax
+	int $0x80

x86/maximum/intel/Makefile

@@ -0,0 +1,3 @@
+default:
+	as maximum.asm --32 -o maximum.o
+	gcc -o maximum.elf -m32 maximum.o -nostdlib

x86/maximum/intel/maximum.asm

@@ -0,0 +1,33 @@
+# edi = index of data_items
+# ebx = largest data item found
+# eax = current data item
+
+.global _start
+.intel_syntax noprefix
+.section .text
+
+_start: 
+	mov edi, 0							# copy 0 into edi - first addresss
+	mov eax, [data_items + edi * 4]		# move the first number (edi * 4) to eax
+	mov ebx, eax						# move ebx to eax
+	jmp start_loop
+	
+start_loop:
+	cmp eax, 0							# check if eax is 0, return value stored in EFLAGS register
+	je loop_exit						# checks EFLAGS if cmp is equal
+	inc edi								# move to the next number (increase index which is edi)
+
+	mov eax, [data_items + edi * 4]		# move the next number (edi * 4) to eax
+	cmp eax, ebx						# compare largest item (ebx) to current item (eax)
+	jle start_loop						# if eax is less than ebx - jump to start_loop
+
+	mov ebx, eax						# move eax to ebx
+	jmp start_loop						# jump back to start_loop
+	
+loop_exit:
+	mov eax, 1							# move '1' into eax (exit syscall)
+	int 0x80							# call kernel interrupt to exit program
+
+.section .data
+	data_items:
+	.long 3, 67, 34, 222, 45, 75, 54, 34, 44, 33, 22, 11, 66, 0