#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 /*<<< orphan*/ ws;

/* Variables and functions */
int /*<<< orphan*/ memset(char *, char, int);
int /*<<< orphan*/ r_cons_printf(char *, char const *, char *, char const *);
int strlen(char const *);
void pair(const char *a, const char *b) {
  char ws[16];
  int al = strlen(a);
  if (!b)
    return;
  memset(ws, ' ', sizeof(ws));
  al = 9 - al;
  if (al < 0)
    al = 0;
  ws[al] = 0;
  r_cons_printf("%s%s%s\n", a, ws, b);
}


x86 assembly (clang, -O0):
<pair>:
push   %rbp
mov    %rsp,%rbp
sub    $0x30,%rsp
mov    %rdi,-0x8(%rbp)
mov    %rsi,-0x10(%rbp)
mov    -0x8(%rbp),%rdi
call   1040 <strlen@plt>
mov    %eax,-0x24(%rbp)
cmpq   $0x0,-0x10(%rbp)
jne    115c <pair+0x2c>
jmp    11ac <pair+0x7c>
lea    -0x20(%rbp),%rdi
mov    $0x20,%esi
mov    $0x10,%edx
call   1050 <memset@plt>
mov    $0x9,%eax
sub    -0x24(%rbp),%eax
mov    %eax,-0x24(%rbp)
cmpl   $0x0,-0x24(%rbp)
jge    118b <pair+0x5b>
movl   $0x0,-0x24(%rbp)
movslq -0x24(%rbp),%rax
movb   $0x0,-0x20(%rbp,%rax,1)
mov    -0x8(%rbp),%rsi
lea    -0x20(%rbp),%rdx
mov    -0x10(%rbp),%rcx
lea    0xe59(%rip),%rdi
call   1030 <r_cons_printf@plt>
add    $0x30,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<pair>:
push   %rbp
push   %r15
push   %r14
push   %rbx
sub    $0x18,%rsp
mov    %rsi,%r14
mov    %rdi,%rbx
call   1040 <strlen@plt>
test   %r14,%r14
je     1186 <pair+0x56>
mov    %eax,%ebp
mov    %rsp,%r15
mov    %r15,%rdi
mov    $0x20,%esi
mov    $0x10,%edx
call   1050 <memset@plt>
mov    $0x9,%eax
xor    %ecx,%ecx
sub    %ebp,%eax
cmovs  %ecx,%eax
movb   $0x0,(%rsp,%rax,1)
lea    0xe88(%rip),%rdi
mov    %rbx,%rsi
mov    %r15,%rdx
mov    %r14,%rcx
call   1030 <r_cons_printf@plt>
add    $0x18,%rsp
pop    %rbx
pop    %r14
pop    %r15
pop    %rbp
ret

LLVM IR (-O0):
@.str = [8 x i8] c"%s%s%s\0A\00"
define void @pair(i8* %0, i8* %1) {
%3 = alloca i8*
%4 = alloca i8*
%5 = alloca [16 x i8]
%6 = alloca i32
store i8* %0, i8** %3
store i8* %1, i8** %4
%7 = load i8*, i8** %3
%8 = call i32 @strlen(i8* %7)
store i32 %8, i32* %6
%9 = load i8*, i8** %4
%10 = icmp ne i8* %9, null
br i1 %10, label %12, label %11
11: ; preds = %2
br label %28
12: ; preds = %2
%13 = getelementptr inbounds [16 x i8], [16 x i8]* %5, i64 0, i64 0
%14 = call i32 @memset(i8* %13, i8 signext 32, i32 16)
%15 = load i32, i32* %6
%16 = sub nsw i32 9, %15
store i32 %16, i32* %6
%17 = load i32, i32* %6
%18 = icmp slt i32 %17, 0
br i1 %18, label %19, label %20
19: ; preds = %12
store i32 0, i32* %6
br label %20
20: ; preds = %19, %12
%21 = load i32, i32* %6
%22 = sext i32 %21 to i64
%23 = getelementptr inbounds [16 x i8], [16 x i8]* %5, i64 0, i64 %22
store i8 0, i8* %23
%24 = load i8*, i8** %3
%25 = getelementptr inbounds [16 x i8], [16 x i8]* %5, i64 0, i64 0
%26 = load i8*, i8** %4
%27 = call i32 @r_cons_printf(i8* getelementptr inbounds ([8 x i8], [8 x i8]* @.str, i64 0, i64 0), i8* %24, i8* %25, i8* %26)
br label %28
28: ; preds = %20, %11
ret void
}

LLVM IR (-O2):
@.str = [8 x i8] c"%s%s%s\0A\00"
define void @pair(i8* %0, i8* %1) {
%3 = alloca [16 x i8]
%4 = getelementptr inbounds [16 x i8], [16 x i8]* %3, i64 0, i64 0
%5 = tail call i32 @strlen(i8* %0)
%6 = icmp eq i8* %1, null
br i1 %6, label %15, label %7
7: ; preds = %2
%8 = call i32 @memset(i8* %4, i8 signext 32, i32 16)
%9 = sub nsw i32 9, %5
%10 = icmp sgt i32 %9, 0
%11 = select i1 %10, i32 %9, i32 0
%12 = zext i32 %11 to i64
%13 = getelementptr inbounds [16 x i8], [16 x i8]* %3, i64 0, i64 %12
store i8 0, i8* %13
%14 = call i32 @r_cons_printf(i8* getelementptr inbounds ([8 x i8], [8 x i8]* @.str, i64 0, i64 0), i8* %0, i8* %4, i8* %1)
br label %15
15: ; preds = %2, %7
ret void
}