#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*/ gets(char *);
scalar_t__ is_pal(char *, int /*<<< orphan*/, scalar_t__);
int /*<<< orphan*/ printf(char *, ...);
scalar_t__ strlen(char *);
int main() {
  char s[100];
  gets(s);
  printf("%s ", s);
  if (is_pal(s, 0, strlen(s) - 1))
    printf("is a palindrome.");
  else
    printf("is NOT a palindrome.");
  return 0;
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
sub    $0x80,%rsp
movl   $0x0,-0x4(%rbp)
lea    -0x70(%rbp),%rdi
call   1050 <gets@plt>
lea    -0x70(%rbp),%rsi
lea    0xe9a(%rip),%rdi
mov    $0x0,%al
call   1040 <printf@plt>
lea    -0x70(%rbp),%rax
mov    %rax,-0x78(%rbp)
lea    -0x70(%rbp),%rdi
call   1030 <strlen@plt>
mov    -0x78(%rbp),%rdi
mov    %rax,%rdx
sub    $0x1,%rdx
xor    %esi,%esi
call   1060 <is_pal@plt>
cmp    $0x0,%rax
je     11ad <main+0x6d>
lea    0xe63(%rip),%rdi
mov    $0x0,%al
call   1040 <printf@plt>
jmp    11bb <main+0x7b>
lea    0xe61(%rip),%rdi
mov    $0x0,%al
call   1040 <printf@plt>
xor    %eax,%eax
add    $0x80,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %rbx
sub    $0x70,%rsp
mov    %rsp,%rbx
mov    %rbx,%rdi
call   1050 <gets@plt>
lea    0xea9(%rip),%rdi
mov    %rbx,%rsi
xor    %eax,%eax
call   1040 <printf@plt>
mov    %rbx,%rdi
call   1030 <strlen@plt>
lea    -0x1(%rax),%rdx
mov    %rbx,%rdi
xor    %esi,%esi
call   1060 <is_pal@plt>
test   %rax,%rax
lea    0xe94(%rip),%rax
lea    0xe7c(%rip),%rdi
cmove  %rax,%rdi
xor    %eax,%eax
call   1040 <printf@plt>
xor    %eax,%eax
add    $0x70,%rsp
pop    %rbx
ret

LLVM IR (-O0):
@.str = [4 x i8] c"%s \00"
@.str.1 = [17 x i8] c"is a palindrome.\00"
@.str.2 = [21 x i8] c"is NOT a palindrome.\00"
define i32 @main() {
%1 = alloca i32
%2 = alloca [100 x i8]
store i32 0, i32* %1
%3 = getelementptr inbounds [100 x i8], [100 x i8]* %2, i64 0, i64 0
%4 = call i32 @gets(i8* %3)
%5 = getelementptr inbounds [100 x i8], [100 x i8]* %2, i64 0, i64 0
%6 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i64 0, i64 0), i8* %5)
%7 = getelementptr inbounds [100 x i8], [100 x i8]* %2, i64 0, i64 0
%8 = getelementptr inbounds [100 x i8], [100 x i8]* %2, i64 0, i64 0
%9 = call i64 @strlen(i8* %8)
%10 = sub nsw i64 %9, 1
%11 = call i64 @is_pal(i8* %7, i32 0, i64 %10)
%12 = icmp ne i64 %11, 0
br i1 %12, label %13, label %15
13: ; preds = %0
%14 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([17 x i8], [17 x i8]* @.str.1, i64 0, i64 0))
br label %17
15: ; preds = %0
%16 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([21 x i8], [21 x i8]* @.str.2, i64 0, i64 0))
br label %17
17: ; preds = %15, %13
ret i32 0
}

LLVM IR (-O2):
@.str = [4 x i8] c"%s \00"
@.str.1 = [17 x i8] c"is a palindrome.\00"
@.str.2 = [21 x i8] c"is NOT a palindrome.\00"
define i32 @main() {
%1 = alloca [100 x i8]
%2 = getelementptr inbounds [100 x i8], [100 x i8]* %1, i64 0, i64 0
%3 = call i32 @gets(i8* %2)
%4 = call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i64 0, i64 0), i8* %2)
%5 = call i64 @strlen(i8* %2)
%6 = add nsw i64 %5, -1
%7 = call i64 @is_pal(i8* %2, i32 0, i64 %6)
%8 = icmp eq i64 %7, 0
%9 = select i1 %8, i8* getelementptr inbounds ([21 x i8], [21 x i8]* @.str.2, i64 0, i64 0), i8* getelementptr inbounds ([17 x i8], [17 x i8]* @.str.1, i64 0, i64 0)
%10 = call i32 (i8*, ...) @printf(i8* dereferenceable(1) %9)
ret i32 0
}