#define NULL ((void *)0)
typedef unsigned long size_t; // Customize by platform.
typedef long intptr_t;
typedef unsigned long uintptr_t;
typedef long scalar_t__; // Either arithmetic or pointer type.
/* By default, we understand bool (as a convenience). */
typedef int bool;
#define false 0
#define true 1

/* Forward declarations */

/* Type definitions */

/* Variables and functions */
int /*<<< orphan*/ printf(char *, ...);
int main(int argc, char *argv[]) {
  int i;
  int sum = 0;
  if (argc < 2) {
    printf("Usage: program-name char\n");
    return 1;
  }
  for (i = 0; i < argc; i++) {
    sum += i;
  }
  printf("Sum is: %d\n", sum);
  return 0;
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
sub    $0x20,%rsp
movl   $0x0,-0x4(%rbp)
mov    %edi,-0x8(%rbp)
mov    %rsi,-0x10(%rbp)
movl   $0x0,-0x18(%rbp)
cmpl   $0x2,-0x8(%rbp)
jge    1151 <main+0x41>
lea    0xec2(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
movl   $0x1,-0x4(%rbp)
jmp    1193 <main+0x83>
movl   $0x0,-0x14(%rbp)
mov    -0x14(%rbp),%eax
cmp    -0x8(%rbp),%eax
jge    117b <main+0x6b>
mov    -0x14(%rbp),%eax
add    -0x18(%rbp),%eax
mov    %eax,-0x18(%rbp)
mov    -0x14(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0x14(%rbp)
jmp    1158 <main+0x48>
mov    -0x18(%rbp),%esi
lea    0xe95(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
movl   $0x0,-0x4(%rbp)
mov    -0x4(%rbp),%eax
add    $0x20,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %rbx
cmp    $0x1,%edi
jg     1139 <main+0x19>
lea    0xedf(%rip),%rdi
call   1030 <puts@plt>
mov    $0x1,%ebx
jmp    115c <main+0x3c>
lea    -0x1(%rdi),%eax
lea    -0x2(%rdi),%ecx
imul   %rax,%rcx
shr    %rcx
lea    (%rcx,%rdi,1),%esi
add    $0xffffffff,%esi
lea    0xead(%rip),%rdi
xor    %ebx,%ebx
xor    %eax,%eax
call   1040 <printf@plt>
mov    %ebx,%eax
pop    %rbx
ret

LLVM IR (-O0):
@.str = [26 x i8] c"Usage: program-name char\0A\00"
@.str.1 = [12 x i8] c"Sum is: %d\0A\00"
define i32 @main(i32 %0, i8** %1) {
%3 = alloca i32
%4 = alloca i32
%5 = alloca i8**
%6 = alloca i32
%7 = alloca i32
store i32 0, i32* %3
store i32 %0, i32* %4
store i8** %1, i8*** %5
store i32 0, i32* %7
%8 = load i32, i32* %4
%9 = icmp slt i32 %8, 2
br i1 %9, label %10, label %12
10: ; preds = %2
%11 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([26 x i8], [26 x i8]* @.str, i64 0, i64 0))
store i32 1, i32* %3
br label %27
12: ; preds = %2
store i32 0, i32* %6
br label %13
13: ; preds = %21, %12
%14 = load i32, i32* %6
%15 = load i32, i32* %4
%16 = icmp slt i32 %14, %15
br i1 %16, label %17, label %24
17: ; preds = %13
%18 = load i32, i32* %6
%19 = load i32, i32* %7
%20 = add nsw i32 %19, %18
store i32 %20, i32* %7
br label %21
21: ; preds = %17
%22 = load i32, i32* %6
%23 = add nsw i32 %22, 1
store i32 %23, i32* %6
br label %13
24: ; preds = %13
%25 = load i32, i32* %7
%26 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([12 x i8], [12 x i8]* @.str.1, i64 0, i64 0), i32 %25)
store i32 0, i32* %3
br label %27
27: ; preds = %24, %10
%28 = load i32, i32* %3
ret i32 %28
}

LLVM IR (-O2):
@.str.1 = [12 x i8] c"Sum is: %d\0A\00"
@str = [25 x i8] c"Usage: program-name char\00"
define i32 @main(i32 %0, i8** nocapture readnone %1) {
%3 = icmp slt i32 %0, 2
br i1 %3, label %4, label %6
4: ; preds = %2
%5 = tail call i32 @puts(i8* dereferenceable(1) getelementptr inbounds ([25 x i8], [25 x i8]* @str, i64 0, i64 0))
br label %17
6: ; preds = %2
%7 = add nsw i32 %0, -1
%8 = zext i32 %7 to i33
%9 = add nsw i32 %0, -2
%10 = zext i32 %9 to i33
%11 = mul i33 %8, %10
%12 = lshr i33 %11, 1
%13 = trunc i33 %12 to i32
%14 = add i32 %13, %0
%15 = add i32 %14, -1
%16 = tail call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([12 x i8], [12 x i8]* @.str.1, i64 0, i64 0), i32 %15)
br label %17
17: ; preds = %6, %4
%18 = phi i32 [ 1, %4 ], [ 0, %6 ]
ret i32 %18
}