#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 EX_USAGE;
int /*<<< orphan*/ execve(char *, char **, int /*<<< orphan*/ *);
int /*<<< orphan*/ fprintf(int /*<<< orphan*/, char *);
int /*<<< orphan*/ stderr;
int main(int argc, char *argv[]) {
  if (argc < 2) {
    fprintf(stderr, "synopsis: exec.exe cmd [arg [...]]\n");
    return EX_USAGE;
  }
  execve(argv[1], &argv[1], NULL);
  return 1;
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
sub    $0x10,%rsp
movl   $0x0,-0x4(%rbp)
mov    %edi,-0x8(%rbp)
mov    %rsi,-0x10(%rbp)
cmpl   $0x2,-0x8(%rbp)
jge    1166 <main+0x46>
mov    0x2e91(%rip),%rax
mov    (%rax),%edi
lea    0xeb0(%rip),%rsi
call   1040 <fprintf@plt>
mov    0x2e8c(%rip),%rax
mov    (%rax),%eax
mov    %eax,-0x4(%rbp)
jmp    1186 <main+0x66>
mov    -0x10(%rbp),%rax
mov    0x8(%rax),%rdi
mov    -0x10(%rbp),%rsi
add    $0x8,%rsi
xor    %eax,%eax
mov    %eax,%edx
call   1030 <execve@plt>
movl   $0x1,-0x4(%rbp)
mov    -0x4(%rbp),%eax
add    $0x10,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %rax
cmp    $0x1,%edi
jg     1146 <main+0x26>
mov    0x2eab(%rip),%rax
mov    (%rax),%edi
lea    0xeca(%rip),%rsi
call   1040 <fprintf@plt>
mov    0x2ea6(%rip),%rax
mov    (%rax),%eax
pop    %rcx
ret
mov    0x8(%rsi),%rdi
add    $0x8,%rsi
xor    %edx,%edx
call   1030 <execve@plt>
mov    $0x1,%eax
pop    %rcx
ret

LLVM IR (-O0):
@stderr = global i32 0
@.str = [36 x i8] c"synopsis: exec.exe cmd [arg [...]]\0A\00"
@EX_USAGE = global i32 0
define i32 @main(i32 %0, i8** %1) {
%3 = alloca i32
%4 = alloca i32
%5 = alloca i8**
store i32 0, i32* %3
store i32 %0, i32* %4
store i8** %1, i8*** %5
%6 = load i32, i32* %4
%7 = icmp slt i32 %6, 2
br i1 %7, label %8, label %12
8: ; preds = %2
%9 = load i32, i32* @stderr
%10 = call i32 @fprintf(i32 %9, i8* getelementptr inbounds ([36 x i8], [36 x i8]* @.str, i64 0, i64 0))
%11 = load i32, i32* @EX_USAGE
store i32 %11, i32* %3
br label %19
12: ; preds = %2
%13 = load i8**, i8*** %5
%14 = getelementptr inbounds i8*, i8** %13, i64 1
%15 = load i8*, i8** %14
%16 = load i8**, i8*** %5
%17 = getelementptr inbounds i8*, i8** %16, i64 1
%18 = call i32 @execve(i8* %15, i8** %17, i32* null)
store i32 1, i32* %3
br label %19
19: ; preds = %12, %8
%20 = load i32, i32* %3
ret i32 %20
}

LLVM IR (-O2):
@stderr = global i32 0
@.str = [36 x i8] c"synopsis: exec.exe cmd [arg [...]]\0A\00"
@EX_USAGE = global i32 0
define i32 @main(i32 %0, i8** %1) {
%3 = icmp slt i32 %0, 2
br i1 %3, label %4, label %8
4: ; preds = %2
%5 = load i32, i32* @stderr
%6 = tail call i32 @fprintf(i32 %5, i8* getelementptr inbounds ([36 x i8], [36 x i8]* @.str, i64 0, i64 0))
%7 = load i32, i32* @EX_USAGE
br label %12
8: ; preds = %2
%9 = getelementptr inbounds i8*, i8** %1, i64 1
%10 = load i8*, i8** %9
%11 = tail call i32 @execve(i8* %10, i8** %9, i32* null)
br label %12
12: ; preds = %8, %4
%13 = phi i32 [ %7, %4 ], [ 1, %8 ]
ret i32 %13
}