#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(int);
int /*<<< orphan*/ memcpy(char *, char const *, int);
int strlen(char const *);
char *mystrdup(const char *s) {
  char *d = NULL;
  if (s) {
    int sl = strlen(s);
    d = (char *)malloc(((sl + 1) * sizeof(char)));
    if (d)
      memcpy(d, s, ((sl + 1) * sizeof(char)));
  }
  return d;
}


x86 assembly (clang, -O0):
<mystrdup>:
push   %rbp
mov    %rsp,%rbp
sub    $0x20,%rsp
mov    %rdi,-0x8(%rbp)
movq   $0x0,-0x10(%rbp)
cmpq   $0x0,-0x8(%rbp)
je     119d <mystrdup+0x6d>
mov    -0x8(%rbp),%rdi
call   1030 <strlen@plt>
mov    %eax,-0x14(%rbp)
mov    -0x14(%rbp),%eax
add    $0x1,%eax
cltq
shl    $0x0,%rax
mov    %eax,%edi
call   1050 <malloc@plt>
mov    %rax,-0x10(%rbp)
cmpq   $0x0,-0x10(%rbp)
je     1198 <mystrdup+0x68>
mov    -0x10(%rbp),%rdi
mov    -0x8(%rbp),%rsi
mov    -0x14(%rbp),%eax
add    $0x1,%eax
cltq
shl    $0x0,%rax
mov    %eax,%edx
call   1040 <memcpy@plt>
jmp    119d <mystrdup+0x6d>
mov    -0x10(%rbp),%rax
add    $0x20,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<mystrdup>:
push   %rbp
push   %r14
push   %rbx
test   %rdi,%rdi
je     1164 <mystrdup+0x34>
mov    %rdi,%rbx
call   1030 <strlen@plt>
mov    %eax,%ebp
add    $0x1,%ebp
mov    %ebp,%edi
call   1050 <malloc@plt>
mov    %rax,%r14
test   %rax,%rax
je     1167 <mystrdup+0x37>
mov    %r14,%rdi
mov    %rbx,%rsi
mov    %ebp,%edx
call   1040 <memcpy@plt>
jmp    1167 <mystrdup+0x37>
xor    %r14d,%r14d
mov    %r14,%rax
pop    %rbx
pop    %r14
pop    %rbp
ret

LLVM IR (-O0):
define i8* @mystrdup(i8* %0) {
%2 = alloca i8*
%3 = alloca i8*
%4 = alloca i32
store i8* %0, i8** %2
store i8* null, i8** %3
%5 = load i8*, i8** %2
%6 = icmp ne i8* %5, null
br i1 %6, label %7, label %29
7: ; preds = %1
%8 = load i8*, i8** %2
%9 = call i32 @strlen(i8* %8)
store i32 %9, i32* %4
%10 = load i32, i32* %4
%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** %3
%17 = load i8*, i8** %3
%18 = icmp ne i8* %17, null
br i1 %18, label %19, label %28
19: ; preds = %7
%20 = load i8*, i8** %3
%21 = load i8*, i8** %2
%22 = load i32, i32* %4
%23 = add nsw i32 %22, 1
%24 = sext i32 %23 to i64
%25 = mul i64 %24, 1
%26 = trunc i64 %25 to i32
%27 = call i32 @memcpy(i8* %20, i8* %21, i32 %26)
br label %28
28: ; preds = %19, %7
br label %29
29: ; preds = %28, %1
%30 = load i8*, i8** %3
ret i8* %30
}

LLVM IR (-O2):
define i8* @mystrdup(i8* %0) {
%2 = icmp eq i8* %0, null
br i1 %2, label %11, label %3
3: ; preds = %1
%4 = tail call i32 @strlen(i8* %0)
%5 = add nsw i32 %4, 1
%6 = tail call i64 @malloc(i32 %5)
%7 = inttoptr i64 %6 to i8*
%8 = icmp eq i64 %6, 0
br i1 %8, label %11, label %9
9: ; preds = %3
%10 = tail call i32 @memcpy(i8* %7, i8* %0, i32 %5)
br label %11
11: ; preds = %3, %9, %1
%12 = phi i8* [ null, %1 ], [ %7, %9 ], [ %7, %3 ]
ret i8* %12
}