From 3a55212f3e57ca4bfea8fdb87b1e85716c575c7d Mon Sep 17 00:00:00 2001
From: Kwarde <kevin@kwarde.com>
Date: Wed, 25 Jun 2025 12:00:05 +0200
Subject: [PATCH] Fix stack usage for printf(), add test

---
 console.asm |  4 +++-
 tests.asm   | 30 ++++++++++++++++++++++++++++++
 2 files changed, 33 insertions(+), 1 deletion(-)

diff --git a/console.asm b/console.asm
index 7d1250b..440db2a 100644
--- a/console.asm
+++ b/console.asm
@@ -89,7 +89,9 @@ printf:
 			je	.rep_s_r9
 
 			;get from stack
-			mov	rsi, qword [rbp + r10*8]
+			; rsp + 6*8 : RIP to printf call (+1), PUSH rbp,r12,r13,rdi (+4), +1 should be tS6
+			mov	rsi, qword [rsp + 5*8 + (r10-5)*8]
+			jmp	.sinsertLoop
 
 			.rep_s_rdx:
 			mov	rsi, rdx
diff --git a/tests.asm b/tests.asm
index 450230f..e8c1481 100644
--- a/tests.asm
+++ b/tests.asm
@@ -68,8 +68,19 @@ section	.rodata
 	msgPuts		db	NL,NL,"# puts()",NL,EOS
 	msgPuts1	db	"puts() test",EOS
 	; printf()
+	testStr		db	"Testing: %s, %s, %s, %s, %s, %s, %s, %s, %s",NL,EOS
+	tS1		db	"one",EOS
+	tS2		db	"two",EOS
+	tS3		db	"three",EOS
+	tS4		db	"four",EOS
+	tS5		db	"five",EOS
+	tS6		db	"six",EOS
+	tS7		db	"seven",EOS
+	tS8		db	"eight",EOS
+	tS9		db	"noin",EOS
 	msgPrintf	db	NL,"# printf()",EOS
 	msgPrintf1	db	"TEST printf()",NL,EOS
+	msgPrintf2	db	"TEST printf(testStr, tS1, tS2, tS3, tS4, tS5, tS6, tS7, tS8, tS9)",NL,EOS
 	; min() / minu()
 	msgMin		db	NL,"# min() / minu()",EOS
 	msgMin1		db	"TEST min(num1, num2): %d",NL,EOS
@@ -204,8 +215,27 @@ main:
 %IF TEST_printf
 	lea	rdi, [rel msgPrintf]
 	call	puts
+
+	; TEST: printf(msgPrintf1)
 	lea	rdi, [rel msgPrintf1]
 	call	printf
+
+	; TEST: printf(testStr, tS1, tS2, tS3, tS4, tS5, tS6, tS7, tS8, tS9)
+	lea	rdi, [rel msgPrintf2]
+	call	printf
+
+	lea	rdi, [rel testStr]
+	lea	rsi, [rel tS1]
+	lea	rdx, [rel tS2]
+	lea	rcx, [rel tS3]
+	lea	r8, [rel tS4]
+	lea	r9, [rel tS5]
+	push	tS9
+	push	tS8
+	push	tS7
+	push	tS6
+	call	printf
+	add	rsp, 32 ;cleanup stack, 8*4
 %ENDIF
 %IF TEST_min
 	lea	rdi, [rel msgMin]