#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 strlen(char *);
void zclean(char *s) {
  int i;
  for (i = 0; i < strlen(s); i++)
    if (s[i] < 32 || s[i] > 'z')
      s[i] = '_';
}


x86 assembly (clang, -O0):
<zclean>:
push   %rbp
mov    %rsp,%rbp
sub    $0x10,%rsp
mov    %rdi,-0x8(%rbp)
movl   $0x0,-0xc(%rbp)
mov    -0xc(%rbp),%eax
mov    %eax,-0x10(%rbp)
mov    -0x8(%rbp),%rdi
call   1030 <strlen@plt>
mov    %eax,%ecx
mov    -0x10(%rbp),%eax
cmp    %ecx,%eax
jge    1188 <zclean+0x78>
mov    -0x8(%rbp),%rax
movslq -0xc(%rbp),%rcx
movsbl (%rax,%rcx,1),%eax
cmp    $0x20,%eax
jl     1169 <zclean+0x59>
mov    -0x8(%rbp),%rax
movslq -0xc(%rbp),%rcx
movsbl (%rax,%rcx,1),%eax
cmp    $0x7a,%eax
jle    1175 <zclean+0x65>
mov    -0x8(%rbp),%rax
movslq -0xc(%rbp),%rcx
movb   $0x5f,(%rax,%rcx,1)
jmp    117a <zclean+0x6a>
mov    -0xc(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0xc(%rbp)
jmp    1123 <zclean+0x13>
add    $0x10,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<zclean>:
push   %r14
push   %rbx
push   %rax
mov    %rdi,%r14
call   1030 <strlen@plt>
test   %eax,%eax
jle    1155 <zclean+0x45>
xor    %ebx,%ebx
jmp    1143 <zclean+0x33>
cs nopw 0x0(%rax,%rax,1)
xchg   %ax,%ax
add    $0x1,%rbx
mov    %r14,%rdi
call   1030 <strlen@plt>
cltq
cmp    %rax,%rbx
jge    1155 <zclean+0x45>
movzbl (%r14,%rbx,1),%eax
add    $0x85,%al
cmp    $0xa4,%al
ja     1130 <zclean+0x20>
movb   $0x5f,(%r14,%rbx,1)
jmp    1130 <zclean+0x20>
add    $0x8,%rsp
pop    %rbx
pop    %r14
ret

LLVM IR (-O0):
define void @zclean(i8* %0) {
%2 = alloca i8*
%3 = alloca i32
store i8* %0, i8** %2
store i32 0, i32* %3
br label %4
4: ; preds = %31, %1
%5 = load i32, i32* %3
%6 = load i8*, i8** %2
%7 = call i32 @strlen(i8* %6)
%8 = icmp slt i32 %5, %7
br i1 %8, label %9, label %34
9: ; preds = %4
%10 = load i8*, i8** %2
%11 = load i32, i32* %3
%12 = sext i32 %11 to i64
%13 = getelementptr inbounds i8, i8* %10, i64 %12
%14 = load i8, i8* %13
%15 = sext i8 %14 to i32
%16 = icmp slt i32 %15, 32
br i1 %16, label %25, label %17
17: ; preds = %9
%18 = load i8*, i8** %2
%19 = load i32, i32* %3
%20 = sext i32 %19 to i64
%21 = getelementptr inbounds i8, i8* %18, i64 %20
%22 = load i8, i8* %21
%23 = sext i8 %22 to i32
%24 = icmp sgt i32 %23, 122
br i1 %24, label %25, label %30
25: ; preds = %17, %9
%26 = load i8*, i8** %2
%27 = load i32, i32* %3
%28 = sext i32 %27 to i64
%29 = getelementptr inbounds i8, i8* %26, i64 %28
store i8 95, i8* %29
br label %30
30: ; preds = %25, %17
br label %31
31: ; preds = %30
%32 = load i32, i32* %3
%33 = add nsw i32 %32, 1
store i32 %33, i32* %3
br label %4
34: ; preds = %4
ret void
}

LLVM IR (-O2):
define void @zclean(i8* %0) {
%2 = tail call i32 @strlen(i8* %0)
%3 = icmp sgt i32 %2, 0
br i1 %3, label %4, label %16
4: ; preds = %1, %11
%5 = phi i64 [ %12, %11 ], [ 0, %1 ]
%6 = getelementptr inbounds i8, i8* %0, i64 %5
%7 = load i8, i8* %6
%8 = add i8 %7, -123
%9 = icmp ult i8 %8, -91
br i1 %9, label %10, label %11
10: ; preds = %4
store i8 95, i8* %6
br label %11
11: ; preds = %4, %10
%12 = add nuw nsw i64 %5, 1
%13 = tail call i32 @strlen(i8* %0)
%14 = sext i32 %13 to i64
%15 = icmp slt i64 %12, %14
br i1 %15, label %4, label %16
16: ; preds = %11, %1
ret void
}