#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 strlen(char *);
scalar_t__ strncmp(char *, char *, int);
scalar_t__ strstr(char *, char *);
int check_protocol(char *buffer) {
  if (strlen(buffer) < 3)
    return 1;
  if ((strncmp(buffer, "GET", 3) == 0) || (strncmp(buffer, "POST", 4) == 0))
    if (strstr(buffer, "HTTP/1."))
      return 1;
  return 0;
}


x86 assembly (clang, -O0):
<check_protocol>:
push   %rbp
mov    %rsp,%rbp
sub    $0x10,%rsp
mov    %rdi,-0x10(%rbp)
mov    -0x10(%rbp),%rdi
call   1040 <strlen@plt>
cmp    $0x3,%eax
jge    115a <check_protocol+0x2a>
movl   $0x1,-0x4(%rbp)
jmp    11ca <check_protocol+0x9a>
mov    -0x10(%rbp),%rdi
lea    0xe9b(%rip),%rsi
mov    $0x3,%edx
call   1030 <strncmp@plt>
cmp    $0x0,%rax
je     1198 <check_protocol+0x68>
mov    -0x10(%rbp),%rdi
lea    0xe80(%rip),%rsi
mov    $0x4,%edx
call   1030 <strncmp@plt>
cmp    $0x0,%rax
jne    11c3 <check_protocol+0x93>
mov    -0x10(%rbp),%rdi
lea    0xe66(%rip),%rsi
call   1050 <strstr@plt>
cmp    $0x0,%rax
je     11be <check_protocol+0x8e>
movl   $0x1,-0x4(%rbp)
jmp    11ca <check_protocol+0x9a>
jmp    11c3 <check_protocol+0x93>
movl   $0x0,-0x4(%rbp)
mov    -0x4(%rbp),%eax
add    $0x10,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<check_protocol>:
push   %rbp
push   %rbx
push   %rax
mov    %rdi,%rbx
call   1040 <strlen@plt>
mov    $0x1,%ebp
cmp    $0x3,%eax
jl     118d <check_protocol+0x5d>
lea    0xeb4(%rip),%rsi
mov    %rbx,%rdi
mov    $0x3,%edx
call   1030 <strncmp@plt>
test   %rax,%rax
je     1177 <check_protocol+0x47>
lea    0xe9f(%rip),%rsi
mov    %rbx,%rdi
mov    $0x4,%edx
call   1030 <strncmp@plt>
test   %rax,%rax
jne    118b <check_protocol+0x5b>
lea    0xe8b(%rip),%rsi
mov    %rbx,%rdi
call   1050 <strstr@plt>
test   %rax,%rax
jne    118d <check_protocol+0x5d>
xor    %ebp,%ebp
mov    %ebp,%eax
add    $0x8,%rsp
pop    %rbx
pop    %rbp
ret

LLVM IR (-O0):
@.str = [4 x i8] c"GET\00"
@.str.1 = [5 x i8] c"POST\00"
@.str.2 = [8 x i8] c"HTTP/1.\00"
define i32 @check_protocol(i8* %0) {
%2 = alloca i32
%3 = alloca i8*
store i8* %0, i8** %3
%4 = load i8*, i8** %3
%5 = call i32 @strlen(i8* %4)
%6 = icmp slt i32 %5, 3
br i1 %6, label %7, label %8
7: ; preds = %1
store i32 1, i32* %2
br label %23
8: ; preds = %1
%9 = load i8*, i8** %3
%10 = call i64 @strncmp(i8* %9, i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i64 0, i64 0), i32 3)
%11 = icmp eq i64 %10, 0
br i1 %11, label %16, label %12
12: ; preds = %8
%13 = load i8*, i8** %3
%14 = call i64 @strncmp(i8* %13, i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str.1, i64 0, i64 0), i32 4)
%15 = icmp eq i64 %14, 0
br i1 %15, label %16, label %22
16: ; preds = %12, %8
%17 = load i8*, i8** %3
%18 = call i64 @strstr(i8* %17, i8* getelementptr inbounds ([8 x i8], [8 x i8]* @.str.2, i64 0, i64 0))
%19 = icmp ne i64 %18, 0
br i1 %19, label %20, label %21
20: ; preds = %16
store i32 1, i32* %2
br label %23
21: ; preds = %16
br label %22
22: ; preds = %21, %12
store i32 0, i32* %2
br label %23
23: ; preds = %22, %20, %7
%24 = load i32, i32* %2
ret i32 %24
}

LLVM IR (-O2):
@.str = [4 x i8] c"GET\00"
@.str.1 = [5 x i8] c"POST\00"
@.str.2 = [8 x i8] c"HTTP/1.\00"
define i32 @check_protocol(i8* %0) {
%2 = tail call i32 @strlen(i8* %0)
%3 = icmp slt i32 %2, 3
br i1 %3, label %14, label %4
4: ; preds = %1
%5 = tail call i64 @strncmp(i8* %0, i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i64 0, i64 0), i32 3)
%6 = icmp eq i64 %5, 0
br i1 %6, label %10, label %7
7: ; preds = %4
%8 = tail call i64 @strncmp(i8* %0, i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str.1, i64 0, i64 0), i32 4)
%9 = icmp eq i64 %8, 0
br i1 %9, label %10, label %13
10: ; preds = %7, %4
%11 = tail call i64 @strstr(i8* %0, i8* getelementptr inbounds ([8 x i8], [8 x i8]* @.str.2, i64 0, i64 0))
%12 = icmp eq i64 %11, 0
br i1 %12, label %13, label %14
13: ; preds = %10, %7
br label %14
14: ; preds = %10, %1, %13
%15 = phi i32 [ 0, %13 ], [ 1, %1 ], [ 1, %10 ]
ret i32 %15
}