int main() {
  int a, b = 199, c;
  int *pointer_1;
  printf("\n Enter a = ");
  scanf("%d", &a);
  pointer_1 = &a;
  printf("\n Content of a: %3d  Address of a: %d\n ", a, pointer_1);
  printf(" Content of Pointer to a: %d \n", pointer_1);
  *pointer_1 = -200;
  printf("\n Content of a: %3d  Address of a: %d\n ", *pointer_1, pointer_1);
  printf(" Content of Pointer to a: %d \n", pointer_1);
  c = a + b;
  pointer_1 = &c;
  printf("\n Content of c: %3d  Address of c: %d\n ", c, pointer_1);
  printf(" Content of Pointer to c: %d \n\n", pointer_1);
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
sub    $0x20,%rsp
movl   $0xc7,-0x8(%rbp)
lea    0xeca(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
lea    0xec9(%rip),%rdi
lea    -0x4(%rbp),%rsi
mov    $0x0,%al
call   1040 <scanf@plt>
lea    -0x4(%rbp),%rax
mov    %rax,-0x18(%rbp)
mov    -0x4(%rbp),%esi
mov    -0x18(%rbp),%rdx
lea    0xeab(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
mov    -0x18(%rbp),%rsi
lea    0xec1(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
mov    -0x18(%rbp),%rax
movl   $0xffffff38,(%rax)
mov    -0x18(%rbp),%rax
mov    (%rax),%esi
mov    -0x18(%rbp),%rdx
lea    0xe77(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
mov    -0x18(%rbp),%rsi
lea    0xe8d(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
mov    -0x4(%rbp),%eax
add    -0x8(%rbp),%eax
mov    %eax,-0xc(%rbp)
lea    -0xc(%rbp),%rax
mov    %rax,-0x18(%rbp)
mov    -0xc(%rbp),%esi
mov    -0x18(%rbp),%rdx
lea    0xe86(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
mov    -0x18(%rbp),%rsi
lea    0xe9c(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
xor    %eax,%eax
add    $0x20,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %r15
push   %r14
push   %rbx
sub    $0x10,%rsp
lea    0xed0(%rip),%rdi
xor    %eax,%eax
call   1030 <printf@plt>
lea    0xecf(%rip),%rdi
lea    0x8(%rsp),%rbx
mov    %rbx,%rsi
xor    %eax,%eax
call   1040 <scanf@plt>
mov    0x8(%rsp),%esi
lea    0xeb8(%rip),%r14
mov    %r14,%rdi
mov    %rbx,%rdx
xor    %eax,%eax
call   1030 <printf@plt>
lea    0xecc(%rip),%r15
mov    %r15,%rdi
mov    %rbx,%rsi
xor    %eax,%eax
call   1030 <printf@plt>
movl   $0xffffff38,0x8(%rsp)
ff
mov    %r14,%rdi
mov    $0xffffff38,%esi
mov    %rbx,%rdx
xor    %eax,%eax
call   1030 <printf@plt>
mov    %r15,%rdi
mov    %rbx,%rsi
xor    %eax,%eax
call   1030 <printf@plt>
mov    $0xc7,%esi
add    0x8(%rsp),%esi
mov    %esi,0xc(%rsp)
lea    0xea3(%rip),%rdi
lea    0xc(%rsp),%rbx
mov    %rbx,%rdx
xor    %eax,%eax
call   1030 <printf@plt>
lea    0xeb5(%rip),%rdi
mov    %rbx,%rsi
xor    %eax,%eax
call   1030 <printf@plt>
xor    %eax,%eax
add    $0x10,%rsp
pop    %rbx
pop    %r14
pop    %r15
ret

LLVM IR (-O0):
@.str = [13 x i8] c"\0A Enter a = \00"
@.str.1 = [3 x i8] c"%d\00"
@.str.2 = [40 x i8] c"\0A Content of a: %3d Address of a: %d\0A \00"
@.str.3 = [31 x i8] c" Content of Pointer to a: %d \0A\00"
@.str.4 = [40 x i8] c"\0A Content of c: %3d Address of c: %d\0A \00"
@.str.5 = [32 x i8] c" Content of Pointer to c: %d \0A\0A\00"
define i32 @main() {
%1 = alloca i32
%2 = alloca i32
%3 = alloca i32
%4 = alloca i32*
store i32 199, i32* %2
%5 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([13 x i8], [13 x i8]* @.str, i64 0, i64 0))
%6 = call i32 (i8*, ...) @scanf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.1, i64 0, i64 0), i32* %1)
store i32* %1, i32** %4
%7 = load i32, i32* %1
%8 = load i32*, i32** %4
%9 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([40 x i8], [40 x i8]* @.str.2, i64 0, i64 0), i32 %7, i32* %8)
%10 = load i32*, i32** %4
%11 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([31 x i8], [31 x i8]* @.str.3, i64 0, i64 0), i32* %10)
%12 = load i32*, i32** %4
store i32 -200, i32* %12
%13 = load i32*, i32** %4
%14 = load i32, i32* %13
%15 = load i32*, i32** %4
%16 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([40 x i8], [40 x i8]* @.str.2, i64 0, i64 0), i32 %14, i32* %15)
%17 = load i32*, i32** %4
%18 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([31 x i8], [31 x i8]* @.str.3, i64 0, i64 0), i32* %17)
%19 = load i32, i32* %1
%20 = load i32, i32* %2
%21 = add nsw i32 %19, %20
store i32 %21, i32* %3
store i32* %3, i32** %4
%22 = load i32, i32* %3
%23 = load i32*, i32** %4
%24 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([40 x i8], [40 x i8]* @.str.4, i64 0, i64 0), i32 %22, i32* %23)
%25 = load i32*, i32** %4
%26 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([32 x i8], [32 x i8]* @.str.5, i64 0, i64 0), i32* %25)
ret i32 0
}

LLVM IR (-O2):
@.str = [13 x i8] c"\0A Enter a = \00"
@.str.1 = [3 x i8] c"%d\00"
@.str.2 = [40 x i8] c"\0A Content of a: %3d Address of a: %d\0A \00"
@.str.3 = [31 x i8] c" Content of Pointer to a: %d \0A\00"
@.str.4 = [40 x i8] c"\0A Content of c: %3d Address of c: %d\0A \00"
@.str.5 = [32 x i8] c" Content of Pointer to c: %d \0A\0A\00"
define i32 @main() {
%1 = alloca i32
%2 = alloca i32
%3 = bitcast i32* %1 to i8*
%4 = bitcast i32* %2 to i8*
%5 = tail call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([13 x i8], [13 x i8]* @.str, i64 0, i64 0))
%6 = call i32 (i8*, ...) @scanf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.1, i64 0, i64 0), i32* %1)
%7 = load i32, i32* %1
%8 = call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([40 x i8], [40 x i8]* @.str.2, i64 0, i64 0), i32 %7, i32* %1)
%9 = call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([31 x i8], [31 x i8]* @.str.3, i64 0, i64 0), i32* %1)
store i32 -200, i32* %1
%10 = call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([40 x i8], [40 x i8]* @.str.2, i64 0, i64 0), i32 -200, i32* %1)
%11 = call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([31 x i8], [31 x i8]* @.str.3, i64 0, i64 0), i32* %1)
%12 = load i32, i32* %1
%13 = add nsw i32 %12, 199
store i32 %13, i32* %2
%14 = call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([40 x i8], [40 x i8]* @.str.4, i64 0, i64 0), i32 %13, i32* %2)
%15 = call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([32 x i8], [32 x i8]* @.str.5, i64 0, i64 0), i32* %2)
ret i32 0
}