Fixing stack size & access + pick OP

yaglitch.asm

@@ -342,8 +342,8 @@ stack_init:
 	.loop_buff_init:
 		stosd
 		loop .loop_buff_init
-	mov al, 7 * 4
-	mov [tosp], al
+	mov eax, (STACK_SZ - 1) * 4
+	mov [tosp], eax
 
 sdl_init:
 	mov rdi, 0x0000FFFF
@@ -597,7 +597,7 @@ run_glitch:
 		jmp .loop
 	.end_glitch:
 	xor rbx, rbx
-	mov bl, [tosp]
+	mov ebx, [tosp]
 	lea rdi, [stack_buff + rbx]
 	mov eax, [rdi]
 ; DEBUG
@@ -626,13 +626,13 @@ OP:
 		; push rdi (edi) on stack_buff
 		mov eax, edi
 		xor rbx, rbx
-		mov bl, [tosp]
-		add bl, 4
-		cmp bl, 8 * 4
+		mov ebx, [tosp]
+		add ebx, 4
+		cmp ebx, STACK_SZ * 4
 		jl .go_push
-		mov bl, 0
+		mov ebx, 0
 		.go_push:
-			mov [tosp], bl
+			mov [tosp], ebx
 			lea rdi, [stack_buff+rbx]
 			stosd
 		ret
@@ -641,18 +641,18 @@ OP:
 	._pop:
 		; pop eax from stack_buff
 		xor rbx, rbx
-		mov bl, [tosp]
+		mov ebx, [tosp]
 		lea rsi, [stack_buff+rbx]
 		xor rax, rax
 		lodsd
-		test bl, bl
+		test ebx, ebx
 		jz .pop_no_dec
-		sub bl, 4
+		sub ebx, 4
 		jmp .pop_end
 		.pop_no_dec:
-			mov bl, 7 * 4
+			mov ebx, (STACK_SZ-1) * 4
 		.pop_end:
-			mov [tosp], bl
+			mov [tosp], ebx
 		ret
 
 
@@ -666,7 +666,7 @@ OP:
 		cld
 		xor rbx, rbx
 		xor rax, rax
-		mov bl, [tosp]
+		mov ebx, [tosp]
 		lea rsi, [stack_buff+rbx]
 		lodsd
 		and eax, 0xFF
@@ -765,7 +765,7 @@ OP:
 		ret
 	.not:
 		call OP._pop
-		neg eax
+		not eax
 		mov edi, eax
 		call OP._push
 		ret
@@ -781,8 +781,19 @@ OP:
 		call OP._pop
 		inc eax
 		and eax, 0xFF
-		neg eax
-		lea rsi, [stack_buff+eax]
+		mov ebx, 4
+		mov ecx, [tosp]
+		mul ebx ; mul by data size
+		cmp eax, [tosp]
+		jg .pick_loop
+		sub ecx, eax
+		jmp .pick_lea
+		.pick_loop: ; eax > tosp
+		sub eax, ecx
+		mov ecx, (STACK_SZ - 1) * 4
+		sub ecx, eax
+		.pick_lea:
+		lea rsi, [stack_buff+ecx]
 		lodsd
 		push rax
 		call OP._pop