#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*/ printf(char *, char);
unsigned char from_hex(char c) {
  if (c >= '0' && c <= '9')
    return c - '0';
  else if (c >= 'a' && c <= 'f')
    return c - 'a' + 10;
  else if (c >= 'A' && c <= 'F')
    return c - 'A' + 10;
  else {
    printf("Bad hex char %c!\n", c);
    return 0;
  }
}


x86 assembly (clang, -O0):
<from_hex>:
push   %rbp
mov    %rsp,%rbp
sub    $0x10,%rsp
mov    %dil,%al
mov    %al,-0x2(%rbp)
movsbl -0x2(%rbp),%eax
cmp    $0x30,%eax
jl     1147 <from_hex+0x37>
movsbl -0x2(%rbp),%eax
cmp    $0x39,%eax
jg     1147 <from_hex+0x37>
movsbl -0x2(%rbp),%eax
sub    $0x30,%eax
mov    %al,-0x1(%rbp)
jmp    11b3 <from_hex+0xa3>
movsbl -0x2(%rbp),%eax
cmp    $0x61,%eax
jl     1173 <from_hex+0x63>
movsbl -0x2(%rbp),%eax
cmp    $0x66,%eax
jg     1173 <from_hex+0x63>
movsbl -0x2(%rbp),%eax
sub    $0x61,%eax
add    $0xa,%eax
mov    %al,-0x1(%rbp)
jmp    11b3 <from_hex+0xa3>
movsbl -0x2(%rbp),%eax
cmp    $0x41,%eax
jl     119f <from_hex+0x8f>
movsbl -0x2(%rbp),%eax
cmp    $0x46,%eax
jg     119f <from_hex+0x8f>
movsbl -0x2(%rbp),%eax
sub    $0x41,%eax
add    $0xa,%eax
mov    %al,-0x1(%rbp)
jmp    11b3 <from_hex+0xa3>
lea    0xe5a(%rip),%rdi
movsbl -0x2(%rbp),%esi
call   1030 <printf@plt>
movb   $0x0,-0x1(%rbp)
movzbl -0x1(%rbp),%eax
add    $0x10,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<from_hex>:
lea    -0x30(%rdi),%eax
cmp    $0xa,%al
jb     114a <from_hex+0x3a>
lea    -0x61(%rdi),%eax
cmp    $0x5,%al
ja     1125 <from_hex+0x15>
add    $0xa9,%dil
mov    %edi,%eax
ret
lea    -0x41(%rdi),%eax
cmp    $0x5,%al
ja     1133 <from_hex+0x23>
add    $0xc9,%dil
mov    %edi,%eax
ret
push   %rax
movsbl %dil,%esi
lea    0xec1(%rip),%rdi
call   1030 <printf@plt>
xor    %eax,%eax
add    $0x8,%rsp
ret

LLVM IR (-O0):
@.str = [18 x i8] c"Bad hex char %c!\0A\00"
define zeroext i8 @from_hex(i8 signext %0) {
%2 = alloca i8
%3 = alloca i8
store i8 %0, i8* %3
%4 = load i8, i8* %3
%5 = sext i8 %4 to i32
%6 = icmp sge i32 %5, 48
br i1 %6, label %7, label %16
7: ; preds = %1
%8 = load i8, i8* %3
%9 = sext i8 %8 to i32
%10 = icmp sle i32 %9, 57
br i1 %10, label %11, label %16
11: ; preds = %7
%12 = load i8, i8* %3
%13 = sext i8 %12 to i32
%14 = sub nsw i32 %13, 48
%15 = trunc i32 %14 to i8
store i8 %15, i8* %2
br label %47
16: ; preds = %7, %1
%17 = load i8, i8* %3
%18 = sext i8 %17 to i32
%19 = icmp sge i32 %18, 97
br i1 %19, label %20, label %30
20: ; preds = %16
%21 = load i8, i8* %3
%22 = sext i8 %21 to i32
%23 = icmp sle i32 %22, 102
br i1 %23, label %24, label %30
24: ; preds = %20
%25 = load i8, i8* %3
%26 = sext i8 %25 to i32
%27 = sub nsw i32 %26, 97
%28 = add nsw i32 %27, 10
%29 = trunc i32 %28 to i8
store i8 %29, i8* %2
br label %47
30: ; preds = %20, %16
%31 = load i8, i8* %3
%32 = sext i8 %31 to i32
%33 = icmp sge i32 %32, 65
br i1 %33, label %34, label %44
34: ; preds = %30
%35 = load i8, i8* %3
%36 = sext i8 %35 to i32
%37 = icmp sle i32 %36, 70
br i1 %37, label %38, label %44
38: ; preds = %34
%39 = load i8, i8* %3
%40 = sext i8 %39 to i32
%41 = sub nsw i32 %40, 65
%42 = add nsw i32 %41, 10
%43 = trunc i32 %42 to i8
store i8 %43, i8* %2
br label %47
44: ; preds = %34, %30
%45 = load i8, i8* %3
%46 = call i32 @printf(i8* getelementptr inbounds ([18 x i8], [18 x i8]* @.str, i64 0, i64 0), i8 signext %45)
store i8 0, i8* %2
br label %47
47: ; preds = %44, %38, %24, %11
%48 = load i8, i8* %2
ret i8 %48
}

LLVM IR (-O2):
@.str = [18 x i8] c"Bad hex char %c!\0A\00"
define zeroext i8 @from_hex(i8 signext %0) {
%2 = add i8 %0, -48
%3 = icmp ult i8 %2, 10
br i1 %3, label %16, label %4
4: ; preds = %1
%5 = add i8 %0, -97
%6 = icmp ult i8 %5, 6
br i1 %6, label %7, label %9
7: ; preds = %4
%8 = add nsw i8 %0, -87
br label %16
9: ; preds = %4
%10 = add i8 %0, -65
%11 = icmp ult i8 %10, 6
br i1 %11, label %12, label %14
12: ; preds = %9
%13 = add nsw i8 %0, -55
br label %16
14: ; preds = %9
%15 = tail call i32 @printf(i8* getelementptr inbounds ([18 x i8], [18 x i8]* @.str, i64 0, i64 0), i8 signext %0)
br label %16
16: ; preds = %1, %14, %12, %7
%17 = phi i8 [ %8, %7 ], [ %13, %12 ], [ 0, %14 ], [ %2, %1 ]
ret i8 %17
}