#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*/ free(unsigned char *);
unsigned char *malloc(int const);
int /*<<< orphan*/ memset(unsigned char *, int /*<<< orphan*/, int const);
int /*<<< orphan*/ printf(char *, ...);
int /*<<< orphan*/ prng_bytes(unsigned char *, int const);
int main() {
  const int memsize = 9;
  unsigned char *mem = malloc(memsize);
  memset(mem, 0, memsize);
  prng_bytes(mem, memsize - 1);
  for (int i = 0; i < memsize; i++) {
    printf("%02x ", mem[i]);
  }
  printf("\n");
  free(mem);
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
sub    $0x20,%rsp
movl   $0x0,-0x4(%rbp)
movl   $0x9,-0x8(%rbp)
mov    $0x9,%edi
call   1060 <malloc@plt>
mov    %rax,-0x10(%rbp)
mov    -0x10(%rbp),%rdi
xor    %esi,%esi
mov    $0x9,%edx
call   1050 <memset@plt>
mov    -0x10(%rbp),%rdi
mov    $0x8,%esi
call   1070 <prng_bytes@plt>
movl   $0x0,-0x14(%rbp)
cmpl   $0x9,-0x14(%rbp)
jge    11cb <main+0x7b>
mov    -0x10(%rbp),%rax
movslq -0x14(%rbp),%rcx
movzbl (%rax,%rcx,1),%esi
lea    0xe4a(%rip),%rdi
mov    $0x0,%al
call   1040 <printf@plt>
mov    -0x14(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0x14(%rbp)
jmp    1199 <main+0x49>
lea    0xe34(%rip),%rdi
mov    $0x0,%al
call   1040 <printf@plt>
mov    -0x10(%rbp),%rdi
call   1030 <free@plt>
mov    -0x4(%rbp),%eax
add    $0x20,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %r14
push   %rbx
push   %rax
mov    $0x9,%edi
call   1070 <malloc@plt>
mov    %rax,%rbx
mov    %rax,%rdi
xor    %esi,%esi
mov    $0x9,%edx
call   1060 <memset@plt>
mov    %rbx,%rdi
mov    $0x8,%esi
call   1080 <prng_bytes@plt>
movzbl (%rbx),%esi
lea    0xe69(%rip),%r14
mov    %r14,%rdi
xor    %eax,%eax
call   1050 <printf@plt>
movzbl 0x1(%rbx),%esi
mov    %r14,%rdi
xor    %eax,%eax
call   1050 <printf@plt>
movzbl 0x2(%rbx),%esi
mov    %r14,%rdi
xor    %eax,%eax
call   1050 <printf@plt>
movzbl 0x3(%rbx),%esi
mov    %r14,%rdi
xor    %eax,%eax
call   1050 <printf@plt>
movzbl 0x4(%rbx),%esi
mov    %r14,%rdi
xor    %eax,%eax
call   1050 <printf@plt>
movzbl 0x5(%rbx),%esi
mov    %r14,%rdi
xor    %eax,%eax
call   1050 <printf@plt>
movzbl 0x6(%rbx),%esi
mov    %r14,%rdi
xor    %eax,%eax
call   1050 <printf@plt>
movzbl 0x7(%rbx),%esi
mov    %r14,%rdi
xor    %eax,%eax
call   1050 <printf@plt>
movzbl 0x8(%rbx),%esi
mov    %r14,%rdi
xor    %eax,%eax
call   1050 <printf@plt>
mov    $0xa,%edi
call   1040 <putchar@plt>
mov    %rbx,%rdi
call   1030 <free@plt>
xor    %eax,%eax
add    $0x8,%rsp
pop    %rbx
pop    %r14
ret

LLVM IR (-O0):
@.str = [6 x i8] c"%02x \00"
@.str.1 = [2 x i8] c"\0A\00"
define i32 @main() {
%1 = alloca i32
%2 = alloca i32
%3 = alloca i8*
%4 = alloca i32
store i32 0, i32* %1
store i32 9, i32* %2
%5 = call i8* @malloc(i32 9)
store i8* %5, i8** %3
%6 = load i8*, i8** %3
%7 = call i32 @memset(i8* %6, i32 0, i32 9)
%8 = load i8*, i8** %3
%9 = call i32 @prng_bytes(i8* %8, i32 8)
store i32 0, i32* %4
br label %10
10: ; preds = %21, %0
%11 = load i32, i32* %4
%12 = icmp slt i32 %11, 9
br i1 %12, label %13, label %24
13: ; preds = %10
%14 = load i8*, i8** %3
%15 = load i32, i32* %4
%16 = sext i32 %15 to i64
%17 = getelementptr inbounds i8, i8* %14, i64 %16
%18 = load i8, i8* %17
%19 = zext i8 %18 to i32
%20 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([6 x i8], [6 x i8]* @.str, i64 0, i64 0), i32 %19)
br label %21
21: ; preds = %13
%22 = load i32, i32* %4
%23 = add nsw i32 %22, 1
store i32 %23, i32* %4
br label %10
24: ; preds = %10
%25 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([2 x i8], [2 x i8]* @.str.1, i64 0, i64 0))
%26 = load i8*, i8** %3
%27 = call i32 @free(i8* %26)
%28 = load i32, i32* %1
ret i32 %28
}

LLVM IR (-O2):
@.str = [6 x i8] c"%02x \00"
define i32 @main() {
%1 = tail call dereferenceable_or_null(9) i8* @malloc(i32 9)
%2 = tail call i32 @memset(i8* %1, i32 0, i32 9)
%3 = tail call i32 @prng_bytes(i8* %1, i32 8)
%4 = load i8, i8* %1
%5 = zext i8 %4 to i32
%6 = tail call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([6 x i8], [6 x i8]* @.str, i64 0, i64 0), i32 %5)
%7 = getelementptr inbounds i8, i8* %1, i64 1
%8 = load i8, i8* %7
%9 = zext i8 %8 to i32
%10 = tail call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([6 x i8], [6 x i8]* @.str, i64 0, i64 0), i32 %9)
%11 = getelementptr inbounds i8, i8* %1, i64 2
%12 = load i8, i8* %11
%13 = zext i8 %12 to i32
%14 = tail call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([6 x i8], [6 x i8]* @.str, i64 0, i64 0), i32 %13)
%15 = getelementptr inbounds i8, i8* %1, i64 3
%16 = load i8, i8* %15
%17 = zext i8 %16 to i32
%18 = tail call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([6 x i8], [6 x i8]* @.str, i64 0, i64 0), i32 %17)
%19 = getelementptr inbounds i8, i8* %1, i64 4
%20 = load i8, i8* %19
%21 = zext i8 %20 to i32
%22 = tail call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([6 x i8], [6 x i8]* @.str, i64 0, i64 0), i32 %21)
%23 = getelementptr inbounds i8, i8* %1, i64 5
%24 = load i8, i8* %23
%25 = zext i8 %24 to i32
%26 = tail call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([6 x i8], [6 x i8]* @.str, i64 0, i64 0), i32 %25)
%27 = getelementptr inbounds i8, i8* %1, i64 6
%28 = load i8, i8* %27
%29 = zext i8 %28 to i32
%30 = tail call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([6 x i8], [6 x i8]* @.str, i64 0, i64 0), i32 %29)
%31 = getelementptr inbounds i8, i8* %1, i64 7
%32 = load i8, i8* %31
%33 = zext i8 %32 to i32
%34 = tail call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([6 x i8], [6 x i8]* @.str, i64 0, i64 0), i32 %33)
%35 = getelementptr inbounds i8, i8* %1, i64 8
%36 = load i8, i8* %35
%37 = zext i8 %36 to i32
%38 = tail call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([6 x i8], [6 x i8]* @.str, i64 0, i64 0), i32 %37)
%39 = tail call i32 @putchar(i32 10)
%40 = tail call i32 @free(i8* %1)
ret i32 0
}