#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 /*<<< orphan*/ fprintf(int /*<<< orphan*/, char *, unsigned char *,
                           unsigned char *, unsigned char *);
scalar_t__ malloc(int);
int /*<<< orphan*/ sprintf(char *, char *, unsigned char *, unsigned char *);
int /*<<< orphan*/ stderr;
int strlen(char *);
unsigned char *clone2strings(unsigned char *s1, unsigned char *s2) {
  unsigned char *res;
  res = (unsigned char *)malloc((strlen((char *)s1) + strlen((char *)s2) + 1) *
                                sizeof(unsigned char));
  sprintf((char *)res, "%s%s", s1, s2);
  if (0)
    fprintf(stderr, "clone2strings(%s, %s) = %s\n", s1, s2, res);
  return res;
}


x86 assembly (clang, -O0):
<clone2strings>:
push   %rbp
mov    %rsp,%rbp
sub    $0x20,%rsp
mov    %rdi,-0x8(%rbp)
mov    %rsi,-0x10(%rbp)
mov    -0x8(%rbp),%rdi
call   1030 <strlen@plt>
mov    %eax,-0x1c(%rbp)
mov    -0x10(%rbp),%rdi
call   1030 <strlen@plt>
mov    %eax,%ecx
mov    -0x1c(%rbp),%eax
add    %ecx,%eax
add    $0x1,%eax
cltq
shl    $0x0,%rax
mov    %eax,%edi
call   1040 <malloc@plt>
mov    %rax,-0x18(%rbp)
mov    -0x18(%rbp),%rdi
mov    -0x8(%rbp),%rdx
mov    -0x10(%rbp),%rcx
lea    0xe7d(%rip),%rsi
call   1050 <sprintf@plt>
mov    -0x18(%rbp),%rax
add    $0x20,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<clone2strings>:
push   %r15
push   %r14
push   %r12
push   %rbx
push   %rax
mov    %rsi,%r14
mov    %rdi,%r12
call   1030 <strlen@plt>
mov    %eax,%r15d
mov    %r14,%rdi
call   1030 <strlen@plt>
lea    (%r15,%rax,1),%edi
add    $0x1,%edi
call   1040 <malloc@plt>
mov    %rax,%rbx
lea    0xe9c(%rip),%rsi
mov    %rax,%rdi
mov    %r12,%rdx
mov    %r14,%rcx
call   1050 <sprintf@plt>
mov    %rbx,%rax
add    $0x8,%rsp
pop    %rbx
pop    %r12
pop    %r14
pop    %r15
ret

LLVM IR (-O0):
@.str = [5 x i8] c"%s%s\00"
@stderr = global i32 0
define i8* @clone2strings(i8* %0, i8* %1) {
%3 = alloca i8*
%4 = alloca i8*
%5 = alloca i8*
store i8* %0, i8** %3
store i8* %1, i8** %4
%6 = load i8*, i8** %3
%7 = call i32 @strlen(i8* %6)
%8 = load i8*, i8** %4
%9 = call i32 @strlen(i8* %8)
%10 = add nsw i32 %7, %9
%11 = add nsw i32 %10, 1
%12 = sext i32 %11 to i64
%13 = mul i64 %12, 1
%14 = trunc i64 %13 to i32
%15 = call i64 @malloc(i32 %14)
%16 = inttoptr i64 %15 to i8*
store i8* %16, i8** %5
%17 = load i8*, i8** %5
%18 = load i8*, i8** %3
%19 = load i8*, i8** %4
%20 = call i32 @sprintf(i8* %17, i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str, i64 0, i64 0), i8* %18, i8* %19)
%21 = load i8*, i8** %5
ret i8* %21
}

LLVM IR (-O2):
@.str = [5 x i8] c"%s%s\00"
@stderr = global i32 0
define i8* @clone2strings(i8* %0, i8* %1) {
%3 = tail call i32 @strlen(i8* %0)
%4 = tail call i32 @strlen(i8* %1)
%5 = add i32 %3, 1
%6 = add i32 %5, %4
%7 = tail call i64 @malloc(i32 %6)
%8 = inttoptr i64 %7 to i8*
%9 = tail call i32 @sprintf(i8* dereferenceable(1) %8, i8* dereferenceable(1) getelementptr inbounds ([5 x i8], [5 x i8]* @.str, i64 0, i64 0), i8* %0, i8* %1)
ret i8* %8
}