#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[]) {
  if (argc != 2) {
    printf("Use -h for help\n");
    return 0;
  }
  char flag = argv[1][1];
  switch (flag) {
  case 'h':
    printf("Use:\n\t-h for help\n\t-a for saying hello\n\t-B for saying "
           "goodbye\n");
    return 0;
  case 'a':
    printf("Hello world!\n");
    return 0;
  case 'B':
    printf("Goodbye world!\n");
    return 0;
  default:
    printf("Use:\n\t-h for help\n\t-a for saying hello\n\t-B for saying "
           "goodbye\n");
    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)
cmpl   $0x2,-0x8(%rbp)
je     1148 <main+0x38>
lea    0xec9(%rip),%rdi
call   1030 <printf@plt>
movl   $0x0,-0x4(%rbp)
jmp    11e8 <main+0xd8>
mov    -0x10(%rbp),%rax
mov    0x8(%rax),%rax
mov    0x1(%rax),%al
mov    %al,-0x11(%rbp)
movsbl -0x11(%rbp),%eax
mov    %eax,-0x18(%rbp)
sub    $0x42,%eax
je     11bd <main+0xad>
jmp    116b <main+0x5b>
mov    -0x18(%rbp),%eax
sub    $0x61,%eax
je     11a5 <main+0x95>
jmp    117c <main+0x6c>
mov    -0x18(%rbp),%eax
sub    $0x68,%eax
jne    11d5 <main+0xc5>
jmp    118d <main+0x7d>
lea    0xe7d(%rip),%rdi
call   1030 <printf@plt>
movl   $0x0,-0x4(%rbp)
jmp    11e8 <main+0xd8>
lea    0xea4(%rip),%rdi
call   1030 <printf@plt>
movl   $0x0,-0x4(%rbp)
jmp    11e8 <main+0xd8>
lea    0xe9a(%rip),%rdi
call   1030 <printf@plt>
movl   $0x0,-0x4(%rbp)
jmp    11e8 <main+0xd8>
lea    0xe35(%rip),%rdi
call   1030 <printf@plt>
movl   $0x0,-0x4(%rbp)
mov    -0x4(%rbp),%eax
add    $0x20,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %rax
cmp    $0x2,%edi
jne    1131 <main+0x21>
mov    0x8(%rsi),%rax
movsbl 0x1(%rax),%eax
cmp    $0x42,%eax
je     113a <main+0x2a>
cmp    $0x61,%eax
jne    1143 <main+0x33>
lea    0xee0(%rip),%rdi
jmp    114a <main+0x3a>
lea    0xf22(%rip),%rdi
jmp    114a <main+0x3a>
lea    0xebf(%rip),%rdi
jmp    114a <main+0x3a>
lea    0xed2(%rip),%rdi
call   1030 <puts@plt>
xor    %eax,%eax
pop    %rcx
ret

LLVM IR (-O0):
@.str = [17 x i8] c"Use -h for help\0A\00"
@.str.1 = [63 x i8] c"Use:\0A\09-h for help\0A\09-a for saying hello\0A\09-B for saying goodbye\0A\00"
@.str.2 = [14 x i8] c"Hello world!\0A\00"
@.str.3 = [16 x i8] c"Goodbye world!\0A\00"
define i32 @main(i32 %0, i8** %1) {
%3 = alloca i32
%4 = alloca i32
%5 = alloca i8**
%6 = alloca i8
store i32 0, i32* %3
store i32 %0, i32* %4
store i8** %1, i8*** %5
%7 = load i32, i32* %4
%8 = icmp ne i32 %7, 2
br i1 %8, label %9, label %11
9: ; preds = %2
%10 = call i32 @printf(i8* getelementptr inbounds ([17 x i8], [17 x i8]* @.str, i64 0, i64 0))
store i32 0, i32* %3
br label %27
11: ; preds = %2
%12 = load i8**, i8*** %5
%13 = getelementptr inbounds i8*, i8** %12, i64 1
%14 = load i8*, i8** %13
%15 = getelementptr inbounds i8, i8* %14, i64 1
%16 = load i8, i8* %15
store i8 %16, i8* %6
%17 = load i8, i8* %6
%18 = sext i8 %17 to i32
switch i32 %18, label %25 [
i32 104, label %19
i32 97, label %21
i32 66, label %23
]
19: ; preds = %11
%20 = call i32 @printf(i8* getelementptr inbounds ([63 x i8], [63 x i8]* @.str.1, i64 0, i64 0))
store i32 0, i32* %3
br label %27
21: ; preds = %11
%22 = call i32 @printf(i8* getelementptr inbounds ([14 x i8], [14 x i8]* @.str.2, i64 0, i64 0))
store i32 0, i32* %3
br label %27
23: ; preds = %11
%24 = call i32 @printf(i8* getelementptr inbounds ([16 x i8], [16 x i8]* @.str.3, i64 0, i64 0))
store i32 0, i32* %3
br label %27
25: ; preds = %11
%26 = call i32 @printf(i8* getelementptr inbounds ([63 x i8], [63 x i8]* @.str.1, i64 0, i64 0))
store i32 0, i32* %3
br label %27
27: ; preds = %25, %23, %21, %19, %9
%28 = load i32, i32* %3
ret i32 %28
}

LLVM IR (-O2):
@str = [15 x i8] c"Goodbye world!\00"
@str.4 = [13 x i8] c"Hello world!\00"
@str.6 = [62 x i8] c"Use:\0A\09-h for help\0A\09-a for saying hello\0A\09-B for saying goodbye\00"
@str.7 = [16 x i8] c"Use -h for help\00"
define i32 @main(i32 %0, i8** nocapture %1) {
%3 = icmp eq i32 %0, 2
br i1 %3, label %4, label %13
4: ; preds = %2
%5 = getelementptr inbounds i8*, i8** %1, i64 1
%6 = load i8*, i8** %5
%7 = getelementptr inbounds i8, i8* %6, i64 1
%8 = load i8, i8* %7
%9 = sext i8 %8 to i32
switch i32 %9, label %12 [
i32 104, label %13
i32 97, label %10
i32 66, label %11
]
10: ; preds = %4
br label %13
11: ; preds = %4
br label %13
12: ; preds = %4
br label %13
13: ; preds = %4, %2, %10, %11, %12
%14 = phi i8* [ getelementptr inbounds ([13 x i8], [13 x i8]* @str.4, i64 0, i64 0), %10 ], [ getelementptr inbounds ([15 x i8], [15 x i8]* @str, i64 0, i64 0), %11 ], [ getelementptr inbounds ([62 x i8], [62 x i8]* @str.6, i64 0, i64 0), %12 ], [ getelementptr inbounds ([16 x i8], [16 x i8]* @str.7, i64 0, i64 0), %2 ], [ getelementptr inbounds ([62 x i8], [62 x i8]* @str.6, i64 0, i64 0), %4 ]
%15 = tail call i32 @puts(i8* dereferenceable(1) %14)
ret i32 0
}