#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 my_getline(char *, int);
int /*<<< orphan*/ printf(char *, ...);
int /*<<< orphan*/ reverse(char *, char *, int);
int main() {
  int len = 0;
  char line[1000];
  char rev_line[1000];
  while ((len = my_getline(line, 1000)) > 0) {
    reverse(rev_line, line, len);
    printf("%s", rev_line);
  }
  printf("\n");
  return 0;
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
sub    $0x7e0,%rsp
movl   $0x0,-0x4(%rbp)
movl   $0x0,-0x8(%rbp)
lea    -0x3f0(%rbp),%rdi
mov    $0x3e8,%esi
call   1050 <my_getline@plt>
mov    %eax,-0x8(%rbp)
cmp    $0x0,%eax
jle    1196 <main+0x66>
lea    -0x7e0(%rbp),%rdi
lea    -0x3f0(%rbp),%rsi
mov    -0x8(%rbp),%edx
call   1030 <reverse@plt>
lea    -0x7e0(%rbp),%rsi
lea    0xe76(%rip),%rdi
mov    $0x0,%al
call   1040 <printf@plt>
jmp    1149 <main+0x19>
lea    0xe66(%rip),%rdi
mov    $0x0,%al
call   1040 <printf@plt>
xor    %eax,%eax
add    $0x7e0,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %r15
push   %r14
push   %rbx
sub    $0x7e0,%rsp
mov    %rsp,%rdi
mov    $0x3e8,%esi
call   1060 <my_getline@plt>
test   %eax,%eax
jle    119b <main+0x5b>
lea    0x3f0(%rsp),%r14
mov    %rsp,%rbx
lea    0xe91(%rip),%r15
nop
mov    %r14,%rdi
mov    %rbx,%rsi
mov    %eax,%edx
call   1030 <reverse@plt>
mov    %r15,%rdi
mov    %r14,%rsi
xor    %eax,%eax
call   1050 <printf@plt>
mov    %rbx,%rdi
mov    $0x3e8,%esi
call   1060 <my_getline@plt>
test   %eax,%eax
jg     1170 <main+0x30>
mov    $0xa,%edi
call   1040 <putchar@plt>
xor    %eax,%eax
add    $0x7e0,%rsp
pop    %rbx
pop    %r14
pop    %r15
ret

LLVM IR (-O0):
@.str = [3 x i8] c"%s\00"
@.str.1 = [2 x i8] c"\0A\00"
define i32 @main() {
%1 = alloca i32
%2 = alloca i32
%3 = alloca [1000 x i8]
%4 = alloca [1000 x i8]
store i32 0, i32* %1
store i32 0, i32* %2
br label %5
5: ; preds = %9, %0
%6 = getelementptr inbounds [1000 x i8], [1000 x i8]* %3, i64 0, i64 0
%7 = call i32 @my_getline(i8* %6, i32 1000)
store i32 %7, i32* %2
%8 = icmp sgt i32 %7, 0
br i1 %8, label %9, label %16
9: ; preds = %5
%10 = getelementptr inbounds [1000 x i8], [1000 x i8]* %4, i64 0, i64 0
%11 = getelementptr inbounds [1000 x i8], [1000 x i8]* %3, i64 0, i64 0
%12 = load i32, i32* %2
%13 = call i32 @reverse(i8* %10, i8* %11, i32 %12)
%14 = getelementptr inbounds [1000 x i8], [1000 x i8]* %4, i64 0, i64 0
%15 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str, i64 0, i64 0), i8* %14)
br label %5
16: ; preds = %5
%17 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([2 x i8], [2 x i8]* @.str.1, i64 0, i64 0))
ret i32 0
}

LLVM IR (-O2):
@.str = [3 x i8] c"%s\00"
define i32 @main() {
%1 = alloca [1000 x i8]
%2 = alloca [1000 x i8]
%3 = getelementptr inbounds [1000 x i8], [1000 x i8]* %1, i64 0, i64 0
%4 = getelementptr inbounds [1000 x i8], [1000 x i8]* %2, i64 0, i64 0
%5 = call i32 @my_getline(i8* %3, i32 1000)
%6 = icmp sgt i32 %5, 0
br i1 %6, label %7, label %13
7: ; preds = %0, %7
%8 = phi i32 [ %11, %7 ], [ %5, %0 ]
%9 = call i32 @reverse(i8* %4, i8* %3, i32 %8)
%10 = call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([3 x i8], [3 x i8]* @.str, i64 0, i64 0), i8* %4)
%11 = call i32 @my_getline(i8* %3, i32 1000)
%12 = icmp sgt i32 %11, 0
br i1 %12, label %7, label %13
13: ; preds = %7, %0
%14 = call i32 @putchar(i32 10)
ret i32 0
}