array index and pointer, which is faster?

p is an array and N is a large number. Which of the following two
loops is faster?

Case1:

for(i=0; i<N; i++){
p[i] = i;
}

Case2:

for(i=0; i<N; i++){
*p = i;
p++;
}

It seems that Case 1 needs multiplication/shifting to calculate the
address/index and the second case needs only an ADD operation. But I
tested it, the speed is almost the same. Can anybody tell me why?
Thanks.

For your reference, the assembly code is as follows:

For Case 1
for(i=0; i<N; i++){
0040101B xor ecx,ecx
0040101D lea ecx,[ecx]
p[i] = i;
00401020 mov dword ptr [eax+ecx*4],ecx
00401023 add ecx,1
00401026 cmp ecx,5F5E100h
0040102C jl main+20h (401020h)
//p++;
}

for Case 2, it is:
for(i=0; i<N; i++){
0040101B xor ecx,ecx
0040101D lea ecx,[ecx]
*p = i;
00401020 mov dword ptr [eax],ecx
00401022 add ecx,1
p++;
00401025 add eax,4
00401028 cmp ecx,5F5E100h
0040102E jl main+20h (401020h)
}




.

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