From 7f051416a84e5496282e3ba63336e5b44e827d40 Mon Sep 17 00:00:00 2001
From: "yu.dongliang" <18588496441@163.com>
Date: Sat, 13 Dec 2025 21:46:35 +0800
Subject: [PATCH] _start.s

---
 Makefile |  7 ++++++-
 _start.s | 20 ++++++++++++++++++++
 asm.s    | 19 ++++++++++++++++---
 3 files changed, 42 insertions(+), 4 deletions(-)
 create mode 100644 _start.s

diff --git a/Makefile b/Makefile
index 331097d..2f699c6 100644
--- a/Makefile
+++ b/Makefile
@@ -1,2 +1,7 @@
 all:
-	gcc -fPIE main.c str.s asm.s
+	as _start.s -o _start.o
+	as asm.s -o asm.o
+	ld _start.o asm.o -lc -o a.out
+#	gcc -fPIE main.c str.s asm.s
+clean:
+	rm *.o
diff --git a/_start.s b/_start.s
new file mode 100644
index 0000000..fef28ca
--- /dev/null
+++ b/_start.s
@@ -0,0 +1,20 @@
+.text
+.global _start, asm_main
+
+_start:
+	mov  %rsp, %rsi
+	add  $8,   %rsi   # argv
+	mov  %rsi, %rdx
+1:
+	mov  (%rdx), %rdi
+	add  $8,    %rdx  # envp
+	test %rdi,  %rdi
+	jnz  1b
+
+	mov  (%rsp), %rdi # argc
+
+	call asm_main
+	mov  %rax, %rdi
+	mov  $60,  %rax
+	syscall
+.fill 5, 1, 0
diff --git a/asm.s b/asm.s
index 68a1467..e92ef74 100644
--- a/asm.s
+++ b/asm.s
@@ -3,7 +3,13 @@
 .global asm_main
 
 asm_main:
-#rdi = asm code
+#rdi = argc
+#rsi = argv
+#rdx = envp
+	cmp $2, %rdi
+	jl  5f
+
+	mov 8(%rsi), %rdi
 0:
 	mov %rdi, %rsi
 1:
@@ -28,7 +34,9 @@ asm_main:
 3:#before ',' is operand 1
 4:#before '\n' is operand 2
 	movb $0, (%rdi)
-
+5:
+	push %rax
+	push %rax
 	push %rdi
 	mov  %rsi, %rdi
 	mov  $0, %eax
@@ -37,8 +45,13 @@ asm_main:
 	mov  $10, %rdi
 	call putchar
 	pop  %rdi
+	pop  %rax
+	pop  %rax
+
+	test %al,%al
+	je 6f
 
 	inc %rdi
 	jmp 0b
-5:
+6:
 	ret
-- 
2.25.1