#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 */
scalar_t__ class_upper(char);
int mangle_lrest(char arr[64], int arr_len) {
  int pos;
  for (pos = 0; pos < arr_len; pos++)
    if (class_upper((arr)[(pos)]))
      (arr)[(pos)] ^= 0x20;
  return (arr_len);
}


x86 assembly (clang, -O0):
<mangle_lrest>:
push   %rbp
mov    %rsp,%rbp
sub    $0x10,%rsp
mov    %rdi,-0x8(%rbp)
mov    %esi,-0xc(%rbp)
movl   $0x0,-0x10(%rbp)
mov    -0x10(%rbp),%eax
cmp    -0xc(%rbp),%eax
jge    1172 <mangle_lrest+0x62>
mov    -0x8(%rbp),%rax
movslq -0x10(%rbp),%rcx
movsbl (%rax,%rcx,1),%edi
call   1030 <class_upper@plt>
cmp    $0x0,%rax
je     115f <mangle_lrest+0x4f>
mov    -0x8(%rbp),%rax
movslq -0x10(%rbp),%rcx
movsbl (%rax,%rcx,1),%edx
xor    $0x20,%edx
mov    %dl,(%rax,%rcx,1)
jmp    1164 <mangle_lrest+0x54>
mov    -0x10(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0x10(%rbp)
jmp    1126 <mangle_lrest+0x16>
mov    -0xc(%rbp),%eax
add    $0x10,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<mangle_lrest>:
push   %rbp
push   %r15
push   %r14
push   %rbx
push   %rax
mov    %esi,%r14d
test   %esi,%esi
jle    114d <mangle_lrest+0x3d>
mov    %rdi,%rbx
mov    %r14d,%r15d
xor    %ebp,%ebp
jmp    1139 <mangle_lrest+0x29>
nopl   0x0(%rax,%rax,1)
add    $0x1,%rbp
cmp    %rbp,%r15
je     114d <mangle_lrest+0x3d>
movsbl (%rbx,%rbp,1),%edi
call   1030 <class_upper@plt>
test   %rax,%rax
je     1130 <mangle_lrest+0x20>
xorb   $0x20,(%rbx,%rbp,1)
jmp    1130 <mangle_lrest+0x20>
mov    %r14d,%eax
add    $0x8,%rsp
pop    %rbx
pop    %r14
pop    %r15
pop    %rbp
ret

LLVM IR (-O0):
define i32 @mangle_lrest(i8* %0, i32 %1) {
%3 = alloca i8*
%4 = alloca i32
%5 = alloca i32
store i8* %0, i8** %3
store i32 %1, i32* %4
store i32 0, i32* %5
br label %6
6: ; preds = %28, %2
%7 = load i32, i32* %5
%8 = load i32, i32* %4
%9 = icmp slt i32 %7, %8
br i1 %9, label %10, label %31
10: ; preds = %6
%11 = load i8*, i8** %3
%12 = load i32, i32* %5
%13 = sext i32 %12 to i64
%14 = getelementptr inbounds i8, i8* %11, i64 %13
%15 = load i8, i8* %14
%16 = call i64 @class_upper(i8 signext %15)
%17 = icmp ne i64 %16, 0
br i1 %17, label %18, label %27
18: ; preds = %10
%19 = load i8*, i8** %3
%20 = load i32, i32* %5
%21 = sext i32 %20 to i64
%22 = getelementptr inbounds i8, i8* %19, i64 %21
%23 = load i8, i8* %22
%24 = sext i8 %23 to i32
%25 = xor i32 %24, 32
%26 = trunc i32 %25 to i8
store i8 %26, i8* %22
br label %27
27: ; preds = %18, %10
br label %28
28: ; preds = %27
%29 = load i32, i32* %5
%30 = add nsw i32 %29, 1
store i32 %30, i32* %5
br label %6
31: ; preds = %6
%32 = load i32, i32* %4
ret i32 %32
}

LLVM IR (-O2):
define i32 @mangle_lrest(i8* nocapture %0, i32 returned %1) {
%3 = icmp sgt i32 %1, 0
br i1 %3, label %4, label %18
4: ; preds = %2
%5 = zext i32 %1 to i64
br label %6
6: ; preds = %4, %15
%7 = phi i64 [ 0, %4 ], [ %16, %15 ]
%8 = getelementptr inbounds i8, i8* %0, i64 %7
%9 = load i8, i8* %8
%10 = tail call i64 @class_upper(i8 signext %9)
%11 = icmp eq i64 %10, 0
br i1 %11, label %15, label %12
12: ; preds = %6
%13 = load i8, i8* %8
%14 = xor i8 %13, 32
store i8 %14, i8* %8
br label %15
15: ; preds = %6, %12
%16 = add nuw nsw i64 %7, 1
%17 = icmp eq i64 %16, %5
br i1 %17, label %18, label %6
18: ; preds = %15, %2
ret i32 %1
}