#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__ isspace(char);
int strlen(char *);
int strsh(char *s) {
  int i;
  for (i = strlen(s); i > 0 && isspace(s[i - 1]); i--)
    s[i - 1] = '\0';
  return i;
}


x86 assembly (clang, -O0):
<strsh>:
push   %rbp
mov    %rsp,%rbp
sub    $0x10,%rsp
mov    %rdi,-0x8(%rbp)
mov    -0x8(%rbp),%rdi
call   1030 <strlen@plt>
mov    %eax,-0xc(%rbp)
xor    %eax,%eax
cmpl   $0x0,-0xc(%rbp)
mov    %al,-0xd(%rbp)
jle    1167 <strsh+0x47>
mov    -0x8(%rbp),%rax
mov    -0xc(%rbp),%ecx
sub    $0x1,%ecx
movslq %ecx,%rcx
movsbl (%rax,%rcx,1),%edi
call   1040 <isspace@plt>
cmp    $0x0,%rax
setne  %al
mov    %al,-0xd(%rbp)
mov    -0xd(%rbp),%al
test   $0x1,%al
jne    1177 <strsh+0x57>
jmp    1196 <strsh+0x76>
mov    -0x8(%rbp),%rax
mov    -0xc(%rbp),%ecx
sub    $0x1,%ecx
movslq %ecx,%rcx
movb   $0x0,(%rax,%rcx,1)
mov    -0xc(%rbp),%eax
add    $0xffffffff,%eax
mov    %eax,-0xc(%rbp)
jmp    1138 <strsh+0x18>
mov    -0xc(%rbp),%eax
add    $0x10,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<strsh>:
push   %r15
push   %r14
push   %r12
push   %rbx
push   %rax
mov    %rdi,%r14
call   1030 <strlen@plt>
mov    %eax,%r15d
test   %eax,%eax
jle    116b <strsh+0x4b>
mov    %r15d,%r15d
nopw   0x0(%rax,%rax,1)
lea    -0x1(%r15),%rbx
mov    %ebx,%r12d
movsbl (%r14,%r12,1),%edi
call   1040 <isspace@plt>
test   %rax,%rax
je     116b <strsh+0x4b>
movb   $0x0,(%r14,%r12,1)
lea    0x1(%rbx),%rax
mov    %rbx,%r15
cmp    $0x1,%rax
ja     1140 <strsh+0x20>
xor    %r15d,%r15d
mov    %r15d,%eax
add    $0x8,%rsp
pop    %rbx
pop    %r12
pop    %r14
pop    %r15
ret

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

LLVM IR (-O2):
define i32 @strsh(i8* %0) {
%2 = tail call i32 @strlen(i8* %0)
%3 = icmp sgt i32 %2, 0
br i1 %3, label %4, label %18
4: ; preds = %1
%5 = zext i32 %2 to i64
br label %6
6: ; preds = %4, %14
%7 = phi i64 [ %5, %4 ], [ %8, %14 ]
%8 = add nsw i64 %7, -1
%9 = and i64 %8, 4294967295
%10 = getelementptr inbounds i8, i8* %0, i64 %9
%11 = load i8, i8* %10
%12 = tail call i64 @isspace(i8 signext %11)
%13 = icmp eq i64 %12, 0
br i1 %13, label %16, label %14
14: ; preds = %6
store i8 0, i8* %10
%15 = icmp ugt i64 %7, 1
br i1 %15, label %6, label %18
16: ; preds = %6
%17 = trunc i64 %7 to i32
br label %18
18: ; preds = %14, %16, %1
%19 = phi i32 [ %2, %1 ], [ %17, %16 ], [ 0, %14 ]
ret i32 %19
}