#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__ malloc(size_t);
int /*<<< orphan*/ memset(char *, int /*<<< orphan*/, size_t);
int /*<<< orphan*/ strcat(char *, char *);
int strlen(char *);
char *appendStringAtEnd(char *src, char *content) {
  size_t totalSize = sizeof(char) * (strlen(src) + strlen(content) + 1);
  char *newString = (char *)malloc(totalSize);
  memset(newString, 0, totalSize);
  strcat(newString, src);
  strcat(newString, content);
  return newString;
}


x86 assembly (clang, -O0):
<appendStringAtEnd>:
push   %rbp
mov    %rsp,%rbp
sub    $0x30,%rsp
mov    %rdi,-0x8(%rbp)
mov    %rsi,-0x10(%rbp)
mov    -0x8(%rbp),%rdi
call   1030 <strlen@plt>
mov    %eax,-0x24(%rbp)
mov    -0x10(%rbp),%rdi
call   1030 <strlen@plt>
mov    %eax,%ecx
mov    -0x24(%rbp),%eax
add    %ecx,%eax
add    $0x1,%eax
cltq
shl    $0x0,%rax
mov    %rax,-0x18(%rbp)
mov    -0x18(%rbp),%rdi
call   1050 <malloc@plt>
mov    %rax,-0x20(%rbp)
mov    -0x20(%rbp),%rdi
mov    -0x18(%rbp),%rdx
xor    %esi,%esi
call   1040 <memset@plt>
mov    -0x20(%rbp),%rdi
mov    -0x8(%rbp),%rsi
call   1060 <strcat@plt>
mov    -0x20(%rbp),%rdi
mov    -0x10(%rbp),%rsi
call   1060 <strcat@plt>
mov    -0x20(%rbp),%rax
add    $0x30,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<appendStringAtEnd>:
push   %r15
push   %r14
push   %r12
push   %rbx
push   %rax
mov    %rsi,%r14
mov    %rdi,%r15
call   1030 <strlen@plt>
mov    %eax,%ebx
mov    %r14,%rdi
call   1030 <strlen@plt>
add    %ebx,%eax
add    $0x1,%eax
movslq %eax,%r12
mov    %r12,%rdi
call   1050 <malloc@plt>
mov    %rax,%rbx
mov    %rax,%rdi
xor    %esi,%esi
mov    %r12,%rdx
call   1040 <memset@plt>
mov    %rbx,%rdi
mov    %r15,%rsi
call   1060 <strcat@plt>
mov    %rbx,%rdi
mov    %r14,%rsi
call   1060 <strcat@plt>
mov    %rbx,%rax
add    $0x8,%rsp
pop    %rbx
pop    %r12
pop    %r14
pop    %r15
ret

LLVM IR (-O0):
define i8* @appendStringAtEnd(i8* %0, i8* %1) {
%3 = alloca i8*
%4 = alloca i8*
%5 = alloca i64
%6 = alloca i8*
store i8* %0, i8** %3
store i8* %1, i8** %4
%7 = load i8*, i8** %3
%8 = call i32 @strlen(i8* %7)
%9 = load i8*, i8** %4
%10 = call i32 @strlen(i8* %9)
%11 = add nsw i32 %8, %10
%12 = add nsw i32 %11, 1
%13 = sext i32 %12 to i64
%14 = mul i64 1, %13
store i64 %14, i64* %5
%15 = load i64, i64* %5
%16 = call i64 @malloc(i64 %15)
%17 = inttoptr i64 %16 to i8*
store i8* %17, i8** %6
%18 = load i8*, i8** %6
%19 = load i64, i64* %5
%20 = call i32 @memset(i8* %18, i32 0, i64 %19)
%21 = load i8*, i8** %6
%22 = load i8*, i8** %3
%23 = call i32 @strcat(i8* %21, i8* %22)
%24 = load i8*, i8** %6
%25 = load i8*, i8** %4
%26 = call i32 @strcat(i8* %24, i8* %25)
%27 = load i8*, i8** %6
ret i8* %27
}

LLVM IR (-O2):
define i8* @appendStringAtEnd(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 = sext i32 %6 to i64
%8 = tail call i64 @malloc(i64 %7)
%9 = inttoptr i64 %8 to i8*
%10 = tail call i32 @memset(i8* %9, i32 0, i64 %7)
%11 = tail call i32 @strcat(i8* %9, i8* %0)
%12 = tail call i32 @strcat(i8* %9, i8* %1)
ret i8* %9
}