#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 */
char *malloc(size_t);
int /*<<< orphan*/ sprintf(char *, char *, char const *, char const *,
                           char const *);
int strlen(char const *);
char *prod_merge_two_strings(const char *str1, const char *str2,
                             const char *separator) {
  char *new_str = NULL;
  size_t new_str_len;
  new_str_len = strlen(str1) + strlen(str2) + strlen(separator) + 1;
  new_str = malloc(new_str_len);
  sprintf(new_str, "%s%s%s", str1, separator, str2);
  new_str[new_str_len] = '\0';
  return new_str;
}


x86 assembly (clang, -O0):
<prod_merge_two_strings>:
push   %rbp
mov    %rsp,%rbp
sub    $0x30,%rsp
mov    %rdi,-0x8(%rbp)
mov    %rsi,-0x10(%rbp)
mov    %rdx,-0x18(%rbp)
movq   $0x0,-0x20(%rbp)
mov    -0x8(%rbp),%rdi
call   1030 <strlen@plt>
mov    %eax,-0x30(%rbp)
mov    -0x10(%rbp),%rdi
call   1030 <strlen@plt>
mov    %eax,%ecx
mov    -0x30(%rbp),%eax
add    %ecx,%eax
mov    %eax,-0x2c(%rbp)
mov    -0x18(%rbp),%rdi
call   1030 <strlen@plt>
mov    %eax,%ecx
mov    -0x2c(%rbp),%eax
add    %ecx,%eax
add    $0x1,%eax
cltq
mov    %rax,-0x28(%rbp)
mov    -0x28(%rbp),%rdi
call   1040 <malloc@plt>
mov    %rax,-0x20(%rbp)
mov    -0x20(%rbp),%rdi
mov    -0x8(%rbp),%rdx
mov    -0x18(%rbp),%rcx
mov    -0x10(%rbp),%r8
lea    0xe58(%rip),%rsi
call   1050 <sprintf@plt>
mov    -0x20(%rbp),%rax
mov    -0x28(%rbp),%rcx
movb   $0x0,(%rax,%rcx,1)
mov    -0x20(%rbp),%rax
add    $0x30,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<prod_merge_two_strings>:
push   %rbp
push   %r15
push   %r14
push   %r12
push   %rbx
mov    %rdx,%r14
mov    %rsi,%r15
mov    %rdi,%r12
call   1030 <strlen@plt>
mov    %eax,%ebp
mov    %r15,%rdi
call   1030 <strlen@plt>
mov    %eax,%ebx
mov    %r14,%rdi
call   1030 <strlen@plt>
add    %ebp,%ebx
add    %ebx,%eax
add    $0x1,%eax
movslq %eax,%rbx
mov    %rbx,%rdi
call   1040 <malloc@plt>
mov    %rax,%rbp
lea    0xe8a(%rip),%rsi
mov    %rax,%rdi
mov    %r12,%rdx
mov    %r14,%rcx
mov    %r15,%r8
call   1050 <sprintf@plt>
movb   $0x0,0x0(%rbp,%rbx,1)
mov    %rbp,%rax
pop    %rbx
pop    %r12
pop    %r14
pop    %r15
pop    %rbp
ret

LLVM IR (-O0):
@.str = [7 x i8] c"%s%s%s\00"
define i8* @prod_merge_two_strings(i8* %0, i8* %1, i8* %2) {
%4 = alloca i8*
%5 = alloca i8*
%6 = alloca i8*
%7 = alloca i8*
%8 = alloca i64
store i8* %0, i8** %4
store i8* %1, i8** %5
store i8* %2, i8** %6
store i8* null, i8** %7
%9 = load i8*, i8** %4
%10 = call i32 @strlen(i8* %9)
%11 = load i8*, i8** %5
%12 = call i32 @strlen(i8* %11)
%13 = add nsw i32 %10, %12
%14 = load i8*, i8** %6
%15 = call i32 @strlen(i8* %14)
%16 = add nsw i32 %13, %15
%17 = add nsw i32 %16, 1
%18 = sext i32 %17 to i64
store i64 %18, i64* %8
%19 = load i64, i64* %8
%20 = call i8* @malloc(i64 %19)
store i8* %20, i8** %7
%21 = load i8*, i8** %7
%22 = load i8*, i8** %4
%23 = load i8*, i8** %6
%24 = load i8*, i8** %5
%25 = call i32 @sprintf(i8* %21, i8* getelementptr inbounds ([7 x i8], [7 x i8]* @.str, i64 0, i64 0), i8* %22, i8* %23, i8* %24)
%26 = load i8*, i8** %7
%27 = load i64, i64* %8
%28 = getelementptr inbounds i8, i8* %26, i64 %27
store i8 0, i8* %28
%29 = load i8*, i8** %7
ret i8* %29
}

LLVM IR (-O2):
@.str = [7 x i8] c"%s%s%s\00"
define noalias i8* @prod_merge_two_strings(i8* %0, i8* %1, i8* %2) {
%4 = tail call i32 @strlen(i8* %0)
%5 = tail call i32 @strlen(i8* %1)
%6 = tail call i32 @strlen(i8* %2)
%7 = add i32 %4, 1
%8 = add i32 %7, %5
%9 = add i32 %8, %6
%10 = sext i32 %9 to i64
%11 = tail call i8* @malloc(i64 %10)
%12 = tail call i32 @sprintf(i8* dereferenceable(1) %11, i8* dereferenceable(1) getelementptr inbounds ([7 x i8], [7 x i8]* @.str, i64 0, i64 0), i8* %0, i8* %2, i8* %1)
%13 = getelementptr inbounds i8, i8* %11, i64 %10
store i8 0, i8* %13
ret i8* %11
}