nesdev.org

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struct foo {
	unsigned char X;
	int Y;
	int Z;
};

struct foo B;

void main (void){
	B.X = 4;
	B.Y = 5;
}

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lda     #$04
	sta     _B

	ldx     #$00
	lda     #$05
	sta     _B+1
	stx     _B+1+1

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void main (void){
	struct foo C;

	C.X = 3;
	C.Y = 4;
}

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	jsr     decsp5
	lda     #$03
	ldy     #$00
	sta     (sp),y

	iny
	lda     #$04
	sta     (sp),y
	lda     #$00
	iny
	sta     (sp),y

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struct foo {
   unsigned char X;
   int Y;
   int Z;
};

struct foo B[5];
unsigned char i;

void main (void){
   for ( i = 0; i < 5; ++i ) {
       B[i].X = 4;
       B[i].Y = 123;
   }
}

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struct foo {
   unsigned char X[5];
   int Y[5];
   int Z[5];
};

struct foo B;
unsigned char i;

void main (void){
   for ( i = 0; i < 5; ++i ) {
       B.X[i] = 4;
       B.Y[i] = 123;
   }
}

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const int AllBackgrounds[] = {(int) &n1,(int) &n2,(int) &n3,(int) &n4 };

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const unsigned char * const All_Backgrounds[]={n1,n2,n3,n4};

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UnRLE(BGDaddress);

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void __fastcall__ UnRLE(int data);

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void __fastcall__ UnRLE(const unsigned char *data);

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unsigned char ac[35];
unsigned int  ai[35];

void index_test()
{
	static unsigned char i;

	// 1.
	i = index();
	ac[i] = 5; // 8-bit index on 8-bit array

	// 2.
	i = index();
	ac[i*2] = 6; // index is promoted to 16-bit int

	// 3.
	i = index() * 2;
	ac[i] = 7; // index was implicitly cast back to 8-bit before use

	// 4.
	i = index();
	ai[i] = 8; // index is promoted to 16-bit int by implicit mulitplication by 2
}

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; 1.
; i = index();
	jsr     _index
	sta     L0017
; ac[i] = 5;
	ldy     L0017
	lda     #$05
	sta     _ac,y

; 2.
; i = index();
	jsr     _index
	sta     L0017
; ac[i*2] = 6;
	ldx     #$00
	lda     L0017
	asl     a
	bcc     L3763
	inx
	clc
L3763:	adc     #<(_ac)
	sta     ptr1
	txa
	adc     #>(_ac)
	sta     ptr1+1
	lda     #$06
	ldy     #$00
	sta     (ptr1),y

; 3.
; i = index() * 2;
	jsr     _index
	asl     a
	sta     L0017
; ac[i] = 7;
	ldy     L0017
	lda     #$07
	sta     _ac,y

; 4.
; i = index();
	jsr     _index
	sta     L0017
; ai[i] = 8;
	ldx     #$00
	lda     L0017
	asl     a
	bcc     L3764
	inx
	clc
L3764:	adc     #<(_ai)
	sta     ptr1
	txa
	adc     #>(_ai)
	sta     ptr1+1
	lda     #$08
	ldy     #$00
	sta     (ptr1),y
	iny
	lda     #$00
	sta     (ptr1),y