#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 *);
char *rtrim(char a[1024]) {
  int i = strlen(a) - 1;
  for (i; a[i] == ' ' || a[i] == '\t'; i--) {
    a[i] = '\0';
  }
  return a;
}


x86 assembly (clang, -O0):
<rtrim>:
push   %rbp
mov    %rsp,%rbp
sub    $0x10,%rsp
mov    %rdi,-0x8(%rbp)
mov    -0x8(%rbp),%rdi
call   1030 <strlen@plt>
sub    $0x1,%eax
mov    %eax,-0xc(%rbp)
mov    -0x8(%rbp),%rax
movslq -0xc(%rbp),%rcx
movsbl (%rax,%rcx,1),%ecx
mov    $0x1,%al
cmp    $0x20,%ecx
mov    %al,-0xd(%rbp)
je     115a <rtrim+0x4a>
mov    -0x8(%rbp),%rax
movslq -0xc(%rbp),%rcx
movsbl (%rax,%rcx,1),%eax
cmp    $0x9,%eax
sete   %al
mov    %al,-0xd(%rbp)
mov    -0xd(%rbp),%al
test   $0x1,%al
jne    116a <rtrim+0x5a>
jmp    1184 <rtrim+0x74>
mov    -0x8(%rbp),%rax
movslq -0xc(%rbp),%rcx
movb   $0x0,(%rax,%rcx,1)
mov    -0xc(%rbp),%eax
add    $0xffffffff,%eax
mov    %eax,-0xc(%rbp)
jmp    112b <rtrim+0x1b>
mov    -0x8(%rbp),%rax
add    $0x10,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<rtrim>:
push   %rbx
mov    %rdi,%rbx
call   1030 <strlen@plt>
cltq
add    %rbx,%rax
add    $0xffffffffffffffff,%rax
jmp    1137 <rtrim+0x27>
cs nopw 0x0(%rax,%rax,1)
xchg   %ax,%ax
movb   $0x0,(%rax)
add    $0xffffffffffffffff,%rax
movzbl (%rax),%ecx
cmp    $0x20,%cl
je     1130 <rtrim+0x20>
cmp    $0x9,%cl
je     1130 <rtrim+0x20>
mov    %rbx,%rax
pop    %rbx
ret

LLVM IR (-O0):
define i8* @rtrim(i8* %0) {
%2 = alloca i8*
%3 = alloca i32
store i8* %0, i8** %2
%4 = load i8*, i8** %2
%5 = call i32 @strlen(i8* %4)
%6 = sub nsw i32 %5, 1
store i32 %6, i32* %3
%7 = load i32, i32* %3
br label %8
8: ; preds = %31, %1
%9 = load i8*, i8** %2
%10 = load i32, i32* %3
%11 = sext i32 %10 to i64
%12 = getelementptr inbounds i8, i8* %9, i64 %11
%13 = load i8, i8* %12
%14 = sext i8 %13 to i32
%15 = icmp eq i32 %14, 32
br i1 %15, label %24, label %16
16: ; preds = %8
%17 = load i8*, i8** %2
%18 = load i32, i32* %3
%19 = sext i32 %18 to i64
%20 = getelementptr inbounds i8, i8* %17, i64 %19
%21 = load i8, i8* %20
%22 = sext i8 %21 to i32
%23 = icmp eq i32 %22, 9
br label %24
24: ; preds = %16, %8
%25 = phi i1 [ true, %8 ], [ %23, %16 ]
br i1 %25, label %26, label %34
26: ; preds = %24
%27 = load i8*, i8** %2
%28 = load i32, i32* %3
%29 = sext i32 %28 to i64
%30 = getelementptr inbounds i8, i8* %27, i64 %29
store i8 0, i8* %30
br label %31
31: ; preds = %26
%32 = load i32, i32* %3
%33 = add nsw i32 %32, -1
store i32 %33, i32* %3
br label %8
34: ; preds = %24
%35 = load i8*, i8** %2
ret i8* %35
}

LLVM IR (-O2):
define i8* @rtrim(i8* returned %0) {
%2 = tail call i32 @strlen(i8* %0)
%3 = sext i32 %2 to i64
br label %4
4: ; preds = %9, %1
%5 = phi i64 [ %6, %9 ], [ %3, %1 ]
%6 = add i64 %5, -1
%7 = getelementptr inbounds i8, i8* %0, i64 %6
%8 = load i8, i8* %7
switch i8 %8, label %10 [
i8 32, label %9
i8 9, label %9
]
9: ; preds = %4, %4
store i8 0, i8* %7
br label %4
10: ; preds = %4
ret i8* %0
}