#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__ strcmp(char const *, char const *);
int strlen(char const *);
int tailmatch(const char *s1, const char *tail) {
  int l1 = strlen(s1);
  int l2 = strlen(tail);
  if (l1 < l2)
    return 0;
  return strcmp(s1 + l1 - l2, tail) == 0;
}


x86 assembly (clang, -O0):
<tailmatch>:
push   %rbp
mov    %rsp,%rbp
sub    $0x20,%rsp
mov    %rdi,-0x10(%rbp)
mov    %rsi,-0x18(%rbp)
mov    -0x10(%rbp),%rdi
call   1030 <strlen@plt>
mov    %eax,-0x1c(%rbp)
mov    -0x18(%rbp),%rdi
call   1030 <strlen@plt>
mov    %eax,-0x20(%rbp)
mov    -0x1c(%rbp),%eax
cmp    -0x20(%rbp),%eax
jge    1160 <tailmatch+0x40>
movl   $0x0,-0x4(%rbp)
jmp    118f <tailmatch+0x6f>
mov    -0x10(%rbp),%rdi
movslq -0x1c(%rbp),%rax
add    %rax,%rdi
movslq -0x20(%rbp),%rcx
xor    %eax,%eax
sub    %rcx,%rax
add    %rax,%rdi
mov    -0x18(%rbp),%rsi
call   1040 <strcmp@plt>
cmp    $0x0,%rax
sete   %al
and    $0x1,%al
movzbl %al,%eax
mov    %eax,-0x4(%rbp)
mov    -0x4(%rbp),%eax
add    $0x20,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<tailmatch>:
push   %rbp
push   %r14
push   %rbx
mov    %rsi,%r14
mov    %rdi,%rbx
call   1030 <strlen@plt>
mov    %eax,%ebp
mov    %r14,%rdi
call   1030 <strlen@plt>
mov    %eax,%ecx
xor    %eax,%eax
cmp    %ecx,%ebp
jl     1163 <tailmatch+0x43>
movslq %ebp,%rax
add    %rax,%rbx
movslq %ecx,%rax
sub    %rax,%rbx
mov    %rbx,%rdi
mov    %r14,%rsi
call   1040 <strcmp@plt>
mov    %rax,%rcx
xor    %eax,%eax
test   %rcx,%rcx
sete   %al
pop    %rbx
pop    %r14
pop    %rbp
ret

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

LLVM IR (-O2):
define i32 @tailmatch(i8* %0, i8* %1) {
%3 = tail call i32 @strlen(i8* %0)
%4 = tail call i32 @strlen(i8* %1)
%5 = icmp slt i32 %3, %4
br i1 %5, label %15, label %6
6: ; preds = %2
%7 = sext i32 %3 to i64
%8 = getelementptr inbounds i8, i8* %0, i64 %7
%9 = sext i32 %4 to i64
%10 = sub nsw i64 0, %9
%11 = getelementptr inbounds i8, i8* %8, i64 %10
%12 = tail call i64 @strcmp(i8* %11, i8* %1)
%13 = icmp eq i64 %12, 0
%14 = zext i1 %13 to i32
br label %15
15: ; preds = %2, %6
%16 = phi i32 [ %14, %6 ], [ 0, %2 ]
ret i32 %16
}