#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(int);
int /*<<< orphan*/ memset(char *, int /*<<< orphan*/, int);
int /*<<< orphan*/ snprintf(char *, int, char *, char *, char const *);
int strlen(char const *);
char *append_text_string(char *textin, const char *appendum) {
  int newlen = strlen(textin) + strlen(appendum) + 1;
  char *z = malloc(sizeof(char) * (newlen));
  memset(z, 0, newlen);
  snprintf(z, newlen, "%s%s", textin, appendum);
  return z;
}


x86 assembly (clang, -O0):
<append_text_string>:
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
mov    %eax,-0x14(%rbp)
movslq -0x14(%rbp),%rax
shl    $0x0,%rax
mov    %eax,%edi
call   1060 <malloc@plt>
mov    %rax,-0x20(%rbp)
mov    -0x20(%rbp),%rdi
mov    -0x14(%rbp),%edx
xor    %esi,%esi
call   1050 <memset@plt>
mov    -0x20(%rbp),%rdi
mov    -0x14(%rbp),%esi
mov    -0x8(%rbp),%rcx
mov    -0x10(%rbp),%r8
lea    0xe57(%rip),%rdx
call   1040 <snprintf@plt>
mov    -0x20(%rbp),%rax
add    $0x30,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<append_text_string>:
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    %eax,%ebx
add    $0x1,%ebx
mov    %ebx,%edi
call   1060 <malloc@plt>
mov    %rax,%r12
mov    %rax,%rdi
xor    %esi,%esi
mov    %ebx,%edx
call   1050 <memset@plt>
lea    0xe81(%rip),%rdx
mov    %r12,%rdi
mov    %ebx,%esi
mov    %r15,%rcx
mov    %r14,%r8
call   1040 <snprintf@plt>
mov    %r12,%rax
add    $0x8,%rsp
pop    %rbx
pop    %r12
pop    %r14
pop    %r15
ret

LLVM IR (-O0):
@.str = [5 x i8] c"%s%s\00"
define i8* @append_text_string(i8* %0, i8* %1) {
%3 = alloca i8*
%4 = alloca i8*
%5 = alloca i32
%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
store i32 %12, i32* %5
%13 = load i32, i32* %5
%14 = sext i32 %13 to i64
%15 = mul i64 1, %14
%16 = trunc i64 %15 to i32
%17 = call i8* @malloc(i32 %16)
store i8* %17, i8** %6
%18 = load i8*, i8** %6
%19 = load i32, i32* %5
%20 = call i32 @memset(i8* %18, i32 0, i32 %19)
%21 = load i8*, i8** %6
%22 = load i32, i32* %5
%23 = load i8*, i8** %3
%24 = load i8*, i8** %4
%25 = call i32 @snprintf(i8* %21, i32 %22, i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str, i64 0, i64 0), i8* %23, i8* %24)
%26 = load i8*, i8** %6
ret i8* %26
}

LLVM IR (-O2):
@.str = [5 x i8] c"%s%s\00"
define i8* @append_text_string(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 i8* @malloc(i32 %6)
%8 = tail call i32 @memset(i8* %7, i32 0, i32 %6)
%9 = tail call i32 @snprintf(i8* %7, i32 %6, i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str, i64 0, i64 0), i8* %0, i8* %1)
ret i8* %7
}