#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 */
typedef int uint8_t;

/* Variables and functions */
int /*<<< orphan*/ printf(char *, ...);
void hex_trace(const uint8_t *buffer, int len) {
  int i = 0;
  for (i = 0; i < len; i++) {
    if (buffer[i] < 0x10)
      printf("0");
    printf("%x ", buffer[i] & (~((~0) << 8)));
  }
  printf("\n");
}


x86 assembly (clang, -O0):
<hex_trace>:
push   %rbp
mov    %rsp,%rbp
sub    $0x10,%rsp
mov    %rdi,-0x8(%rbp)
mov    %esi,-0xc(%rbp)
movl   $0x0,-0x10(%rbp)
movl   $0x0,-0x10(%rbp)
mov    -0x10(%rbp),%eax
cmp    -0xc(%rbp),%eax
jge    1186 <hex_trace+0x76>
mov    -0x8(%rbp),%rax
movslq -0x10(%rbp),%rcx
cmpl   $0x10,(%rax,%rcx,4)
jge    1159 <hex_trace+0x49>
lea    0xeae(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
mov    -0x8(%rbp),%rax
movslq -0x10(%rbp),%rcx
mov    (%rax,%rcx,4),%esi
and    $0xff,%esi
lea    0xe91(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
mov    -0x10(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0x10(%rbp)
jmp    112d <hex_trace+0x1d>
lea    0xe79(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
add    $0x10,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<hex_trace>:
push   %r15
push   %r14
push   %r12
push   %rbx
push   %rax
test   %esi,%esi
jle    1170 <hex_trace+0x50>
mov    %rdi,%r12
mov    %esi,%r15d
lea    0xec7(%rip),%r14
xor    %ebx,%ebx
jmp    1156 <hex_trace+0x36>
nopl   (%rax)
movzbl %al,%esi
mov    %r14,%rdi
xor    %eax,%eax
call   1040 <printf@plt>
add    $0x1,%rbx
cmp    %rbx,%r15
je     1170 <hex_trace+0x50>
mov    (%r12,%rbx,4),%eax
cmp    $0xf,%eax
jg     1140 <hex_trace+0x20>
mov    $0x30,%edi
call   1030 <putchar@plt>
movzbl (%r12,%rbx,4),%eax
jmp    1140 <hex_trace+0x20>
mov    $0xa,%edi
add    $0x8,%rsp
pop    %rbx
pop    %r12
pop    %r14
pop    %r15
jmp    1030 <putchar@plt>

LLVM IR (-O0):
@.str = [2 x i8] c"0\00"
@.str.1 = [4 x i8] c"%x \00"
@.str.2 = [2 x i8] c"\0A\00"
define void @hex_trace(i32* %0, i32 %1) {
%3 = alloca i32*
%4 = alloca i32
%5 = alloca i32
store i32* %0, i32** %3
store i32 %1, i32* %4
store i32 0, i32* %5
store i32 0, i32* %5
br label %6
6: ; preds = %27, %2
%7 = load i32, i32* %5
%8 = load i32, i32* %4
%9 = icmp slt i32 %7, %8
br i1 %9, label %10, label %30
10: ; preds = %6
%11 = load i32*, i32** %3
%12 = load i32, i32* %5
%13 = sext i32 %12 to i64
%14 = getelementptr inbounds i32, i32* %11, i64 %13
%15 = load i32, i32* %14
%16 = icmp slt i32 %15, 16
br i1 %16, label %17, label %19
17: ; preds = %10
%18 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([2 x i8], [2 x i8]* @.str, i64 0, i64 0))
br label %19
19: ; preds = %17, %10
%20 = load i32*, i32** %3
%21 = load i32, i32* %5
%22 = sext i32 %21 to i64
%23 = getelementptr inbounds i32, i32* %20, i64 %22
%24 = load i32, i32* %23
%25 = and i32 %24, 255
%26 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str.1, i64 0, i64 0), i32 %25)
br label %27
27: ; preds = %19
%28 = load i32, i32* %5
%29 = add nsw i32 %28, 1
store i32 %29, i32* %5
br label %6
30: ; preds = %6
%31 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([2 x i8], [2 x i8]* @.str.2, i64 0, i64 0))
ret void
}

LLVM IR (-O2):
@.str.1 = [4 x i8] c"%x \00"
define void @hex_trace(i32* nocapture %0, i32 %1) {
%3 = icmp sgt i32 %1, 0
br i1 %3, label %4, label %20
4: ; preds = %2
%5 = zext i32 %1 to i64
br label %6
6: ; preds = %4, %14
%7 = phi i64 [ 0, %4 ], [ %18, %14 ]
%8 = getelementptr inbounds i32, i32* %0, i64 %7
%9 = load i32, i32* %8
%10 = icmp slt i32 %9, 16
br i1 %10, label %11, label %14
11: ; preds = %6
%12 = tail call i32 @putchar(i32 48)
%13 = load i32, i32* %8
br label %14
14: ; preds = %11, %6
%15 = phi i32 [ %13, %11 ], [ %9, %6 ]
%16 = and i32 %15, 255
%17 = tail call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([4 x i8], [4 x i8]* @.str.1, i64 0, i64 0), i32 %16)
%18 = add nuw nsw i64 %7, 1
%19 = icmp eq i64 %18, %5
br i1 %19, label %20, label %6
20: ; preds = %14, %2
%21 = tail call i32 @putchar(i32 10)
ret void
}