#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*/ putchar(char);
int main(void) {
  char rev = 'z';
  while (rev >= 'a') {
    putchar(rev);
    rev--;
  }
  putchar('\n');
  return (0);
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
sub    $0x10,%rsp
movl   $0x0,-0x4(%rbp)
movb   $0x7a,-0x5(%rbp)
movsbl -0x5(%rbp),%eax
cmp    $0x61,%eax
jl     1146 <main+0x36>
movsbl -0x5(%rbp),%edi
call   1030 <putchar@plt>
mov    -0x5(%rbp),%al
add    $0xff,%al
mov    %al,-0x5(%rbp)
jmp    1123 <main+0x13>
mov    $0xa,%edi
call   1030 <putchar@plt>
xor    %eax,%eax
add    $0x10,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %rax
mov    $0x7a,%edi
call   1030 <putchar@plt>
mov    $0x79,%edi
call   1030 <putchar@plt>
mov    $0x78,%edi
call   1030 <putchar@plt>
mov    $0x77,%edi
call   1030 <putchar@plt>
mov    $0x76,%edi
call   1030 <putchar@plt>
mov    $0x75,%edi
call   1030 <putchar@plt>
mov    $0x74,%edi
call   1030 <putchar@plt>
mov    $0x73,%edi
call   1030 <putchar@plt>
mov    $0x72,%edi
call   1030 <putchar@plt>
mov    $0x71,%edi
call   1030 <putchar@plt>
mov    $0x70,%edi
call   1030 <putchar@plt>
mov    $0x6f,%edi
call   1030 <putchar@plt>
mov    $0x6e,%edi
call   1030 <putchar@plt>
mov    $0x6d,%edi
call   1030 <putchar@plt>
mov    $0x6c,%edi
call   1030 <putchar@plt>
mov    $0x6b,%edi
call   1030 <putchar@plt>
mov    $0x6a,%edi
call   1030 <putchar@plt>
mov    $0x69,%edi
call   1030 <putchar@plt>
mov    $0x68,%edi
call   1030 <putchar@plt>
mov    $0x67,%edi
call   1030 <putchar@plt>
mov    $0x66,%edi
call   1030 <putchar@plt>
mov    $0x65,%edi
call   1030 <putchar@plt>
mov    $0x64,%edi
call   1030 <putchar@plt>
mov    $0x63,%edi
call   1030 <putchar@plt>
mov    $0x62,%edi
call   1030 <putchar@plt>
mov    $0x61,%edi
call   1030 <putchar@plt>
mov    $0xa,%edi
call   1030 <putchar@plt>
xor    %eax,%eax
pop    %rcx
ret

LLVM IR (-O0):
define i32 @main() {
%1 = alloca i32
%2 = alloca i8
store i32 0, i32* %1
store i8 122, i8* %2
br label %3
3: ; preds = %7, %0
%4 = load i8, i8* %2
%5 = sext i8 %4 to i32
%6 = icmp sge i32 %5, 97
br i1 %6, label %7, label %12
7: ; preds = %3
%8 = load i8, i8* %2
%9 = call i32 @putchar(i8 signext %8)
%10 = load i8, i8* %2
%11 = add i8 %10, -1
store i8 %11, i8* %2
br label %3
12: ; preds = %3
%13 = call i32 @putchar(i8 signext 10)
ret i32 0
}

LLVM IR (-O2):
define i32 @main() {
%1 = tail call i32 @putchar(i8 signext 122)
%2 = tail call i32 @putchar(i8 signext 121)
%3 = tail call i32 @putchar(i8 signext 120)
%4 = tail call i32 @putchar(i8 signext 119)
%5 = tail call i32 @putchar(i8 signext 118)
%6 = tail call i32 @putchar(i8 signext 117)
%7 = tail call i32 @putchar(i8 signext 116)
%8 = tail call i32 @putchar(i8 signext 115)
%9 = tail call i32 @putchar(i8 signext 114)
%10 = tail call i32 @putchar(i8 signext 113)
%11 = tail call i32 @putchar(i8 signext 112)
%12 = tail call i32 @putchar(i8 signext 111)
%13 = tail call i32 @putchar(i8 signext 110)
%14 = tail call i32 @putchar(i8 signext 109)
%15 = tail call i32 @putchar(i8 signext 108)
%16 = tail call i32 @putchar(i8 signext 107)
%17 = tail call i32 @putchar(i8 signext 106)
%18 = tail call i32 @putchar(i8 signext 105)
%19 = tail call i32 @putchar(i8 signext 104)
%20 = tail call i32 @putchar(i8 signext 103)
%21 = tail call i32 @putchar(i8 signext 102)
%22 = tail call i32 @putchar(i8 signext 101)
%23 = tail call i32 @putchar(i8 signext 100)
%24 = tail call i32 @putchar(i8 signext 99)
%25 = tail call i32 @putchar(i8 signext 98)
%26 = tail call i32 @putchar(i8 signext 97)
%27 = tail call i32 @putchar(i8 signext 10)
ret i32 0
}