#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 partition(int *, int, int);
void qsort(int a[], int begin, int end) {
  int m;
  m = partition(a, begin, end);
  if (begin < m - 1)
    qsort(a, begin, m - 1);
  if (m < end)
    qsort(a, m, end);
}


x86 assembly (clang, -O0):
<qsort>:
push   %rbp
mov    %rsp,%rbp
sub    $0x20,%rsp
mov    %rdi,-0x8(%rbp)
mov    %esi,-0xc(%rbp)
mov    %edx,-0x10(%rbp)
mov    -0x8(%rbp),%rdi
mov    -0xc(%rbp),%esi
mov    -0x10(%rbp),%edx
call   1030 <partition@plt>
mov    %eax,-0x14(%rbp)
mov    -0xc(%rbp),%eax
mov    -0x14(%rbp),%ecx
sub    $0x1,%ecx
cmp    %ecx,%eax
jge    1167 <qsort+0x47>
mov    -0x8(%rbp),%rdi
mov    -0xc(%rbp),%esi
mov    -0x14(%rbp),%edx
sub    $0x1,%edx
call   1040 <qsort@plt>
mov    -0x14(%rbp),%eax
cmp    -0x10(%rbp),%eax
jge    1182 <qsort+0x62>
mov    -0x8(%rbp),%rdi
mov    -0x14(%rbp),%esi
mov    -0x10(%rbp),%edx
call   1040 <qsort@plt>
add    $0x20,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<qsort>:
push   %rbp
push   %r15
push   %r14
push   %rbx
push   %rax
mov    %edx,%r15d
mov    %esi,%ebp
mov    %rdi,%r14
jmp    1147 <qsort+0x27>
cs nopw 0x0(%rax,%rax,1)
nopl   0x0(%rax,%rax,1)
mov    %ebx,%ebp
cmp    %r15d,%ebx
jge    1169 <qsort+0x49>
mov    %r14,%rdi
mov    %ebp,%esi
mov    %r15d,%edx
call   1030 <partition@plt>
mov    %eax,%ebx
lea    -0x1(%rbx),%edx
cmp    %ebp,%edx
jle    1140 <qsort+0x20>
mov    %r14,%rdi
mov    %ebp,%esi
call   1040 <qsort@plt>
jmp    1140 <qsort+0x20>
add    $0x8,%rsp
pop    %rbx
pop    %r14
pop    %r15
pop    %rbp
ret

LLVM IR (-O0):
define void @qsort(i32* %0, i32 %1, i32 %2) {
%4 = alloca i32*
%5 = alloca i32
%6 = alloca i32
%7 = alloca i32
store i32* %0, i32** %4
store i32 %1, i32* %5
store i32 %2, i32* %6
%8 = load i32*, i32** %4
%9 = load i32, i32* %5
%10 = load i32, i32* %6
%11 = call i32 @partition(i32* %8, i32 %9, i32 %10)
store i32 %11, i32* %7
%12 = load i32, i32* %5
%13 = load i32, i32* %7
%14 = sub nsw i32 %13, 1
%15 = icmp slt i32 %12, %14
br i1 %15, label %16, label %21
16: ; preds = %3
%17 = load i32*, i32** %4
%18 = load i32, i32* %5
%19 = load i32, i32* %7
%20 = sub nsw i32 %19, 1
br label %21
21: ; preds = %16, %3
%22 = load i32, i32* %7
%23 = load i32, i32* %6
%24 = icmp slt i32 %22, %23
br i1 %24, label %25, label %29
25: ; preds = %21
%26 = load i32*, i32** %4
%27 = load i32, i32* %7
%28 = load i32, i32* %6
br label %29
29: ; preds = %25, %21
ret void
}

LLVM IR (-O2):
define void @qsort(i32* %0, i32 %1, i32 %2) {
br label %4
4: ; preds = %10, %3
%5 = phi i32 [ %1, %3 ], [ %6, %10 ]
%6 = tail call i32 @partition(i32* %0, i32 %5, i32 %2)
%7 = add nsw i32 %6, -1
%8 = icmp sgt i32 %7, %5
br i1 %8, label %9, label %10
9: ; preds = %4
tail call void @qsort(i32* %0, i32 %5, i32 %7)
br label %10
10: ; preds = %9, %4
%11 = icmp slt i32 %6, %2
br i1 %11, label %4, label %12
12: ; preds = %10
ret void
}