#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 compare(char *, char *);
int /*<<< orphan*/ printf(char *, ...);
int /*<<< orphan*/ scanf(char *, char *);
int main(int argc, char *argv[]) {
  char a[100];
  char b[100];
  printf("Input string a:");
  scanf("%s", a);
  printf("Input string b:");
  scanf("%s", b);
  printf("compare output %d\n", compare(a, b));
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
sub    $0xf0,%rsp
mov    %edi,-0x4(%rbp)
mov    %rsi,-0x10(%rbp)
lea    0xeb7(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
lea    -0x80(%rbp),%rsi
lea    0xeb5(%rip),%rdi
call   1040 <scanf@plt>
lea    0xeac(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
lea    -0xf0(%rbp),%rsi
lea    0xe94(%rip),%rdi
call   1040 <scanf@plt>
lea    -0x80(%rbp),%rdi
lea    -0xf0(%rbp),%rsi
call   1050 <compare@plt>
mov    %eax,%esi
lea    0xe89(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
xor    %eax,%eax
add    $0xf0,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %r15
push   %r14
push   %rbx
sub    $0xe0,%rsp
lea    0xebd(%rip),%rdi
xor    %eax,%eax
call   1030 <printf@plt>
lea    0xebf(%rip),%r15
lea    0x70(%rsp),%r14
mov    %r15,%rdi
mov    %r14,%rsi
call   1040 <scanf@plt>
lea    0xeab(%rip),%rdi
xor    %eax,%eax
call   1030 <printf@plt>
mov    %rsp,%rbx
mov    %r15,%rdi
mov    %rbx,%rsi
call   1040 <scanf@plt>
mov    %r14,%rdi
mov    %rbx,%rsi
call   1050 <compare@plt>
lea    0xe94(%rip),%rdi
mov    %eax,%esi
xor    %eax,%eax
call   1030 <printf@plt>
xor    %eax,%eax
add    $0xe0,%rsp
pop    %rbx
pop    %r14
pop    %r15
ret

LLVM IR (-O0):
@.str = [16 x i8] c"Input string a:\00"
@.str.1 = [3 x i8] c"%s\00"
@.str.2 = [16 x i8] c"Input string b:\00"
@.str.3 = [19 x i8] c"compare output %d\0A\00"
define i32 @main(i32 %0, i8** %1) {
%3 = alloca i32
%4 = alloca i8**
%5 = alloca [100 x i8]
%6 = alloca [100 x i8]
store i32 %0, i32* %3
store i8** %1, i8*** %4
%7 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([16 x i8], [16 x i8]* @.str, i64 0, i64 0))
%8 = getelementptr inbounds [100 x i8], [100 x i8]* %5, i64 0, i64 0
%9 = call i32 @scanf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.1, i64 0, i64 0), i8* %8)
%10 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([16 x i8], [16 x i8]* @.str.2, i64 0, i64 0))
%11 = getelementptr inbounds [100 x i8], [100 x i8]* %6, i64 0, i64 0
%12 = call i32 @scanf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.1, i64 0, i64 0), i8* %11)
%13 = getelementptr inbounds [100 x i8], [100 x i8]* %5, i64 0, i64 0
%14 = getelementptr inbounds [100 x i8], [100 x i8]* %6, i64 0, i64 0
%15 = call i32 @compare(i8* %13, i8* %14)
%16 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([19 x i8], [19 x i8]* @.str.3, i64 0, i64 0), i32 %15)
ret i32 0
}

LLVM IR (-O2):
@.str = [16 x i8] c"Input string a:\00"
@.str.1 = [3 x i8] c"%s\00"
@.str.2 = [16 x i8] c"Input string b:\00"
@.str.3 = [19 x i8] c"compare output %d\0A\00"
define i32 @main(i32 %0, i8** nocapture readnone %1) {
%3 = alloca [100 x i8]
%4 = alloca [100 x i8]
%5 = getelementptr inbounds [100 x i8], [100 x i8]* %3, i64 0, i64 0
%6 = getelementptr inbounds [100 x i8], [100 x i8]* %4, i64 0, i64 0
%7 = tail call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([16 x i8], [16 x i8]* @.str, i64 0, i64 0))
%8 = call i32 @scanf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.1, i64 0, i64 0), i8* %5)
%9 = call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([16 x i8], [16 x i8]* @.str.2, i64 0, i64 0))
%10 = call i32 @scanf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.1, i64 0, i64 0), i8* %6)
%11 = call i32 @compare(i8* %5, i8* %6)
%12 = call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([19 x i8], [19 x i8]* @.str.3, i64 0, i64 0), i32 %11)
ret i32 0
}