#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 */
float M_PI;
float pow(float, int);
int /*<<< orphan*/ printf(char *, ...);
int /*<<< orphan*/ scanf(char *, float *);
int main(void) {
  float radius, area;
  printf("Enter the radius of a circle\n");
  scanf("%f", &radius);
  area = M_PI * pow(radius, 2);
  printf("Area of a circle = %5.2f\n", area);
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
sub    $0x10,%rsp
lea    0xec1(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
lea    0xed1(%rip),%rdi
lea    -0x4(%rbp),%rsi
call   1040 <scanf@plt>
mov    0x2e8b(%rip),%rax
movss  (%rax),%xmm0
movss  %xmm0,-0xc(%rbp)
movss  -0x4(%rbp),%xmm0
mov    $0x2,%edi
call   1050 <pow@plt>
movaps %xmm0,%xmm1
movss  -0xc(%rbp),%xmm0
mulss  %xmm1,%xmm0
movss  %xmm0,-0x8(%rbp)
movss  -0x8(%rbp),%xmm0
cvtss2sd %xmm0,%xmm0
lea    0xe8b(%rip),%rdi
mov    $0x1,%al
call   1030 <printf@plt>
xor    %eax,%eax
add    $0x10,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %rax
lea    0xed5(%rip),%rdi
call   1030 <puts@plt>
lea    0xeac(%rip),%rdi
lea    0x4(%rsp),%rsi
call   1050 <scanf@plt>
mov    0x2e83(%rip),%rax
movss  (%rax),%xmm0
movss  %xmm0,(%rsp)
movss  0x4(%rsp),%xmm0
mov    $0x2,%edi
call   1060 <pow@plt>
mulss  (%rsp),%xmm0
cvtss2sd %xmm0,%xmm0
lea    0xe75(%rip),%rdi
mov    $0x1,%al
call   1040 <printf@plt>
xor    %eax,%eax
pop    %rcx
ret

LLVM IR (-O0):
@.str = [30 x i8] c"Enter the radius of a circle\0A\00"
@.str.1 = [3 x i8] c"%f\00"
@M_PI = global float 0.000000e+00
@.str.2 = [26 x i8] c"Area of a circle = %5.2f\0A\00"
define i32 @main() {
%1 = alloca float
%2 = alloca float
%3 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([30 x i8], [30 x i8]* @.str, i64 0, i64 0))
%4 = call i32 @scanf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.1, i64 0, i64 0), float* %1)
%5 = load float, float* @M_PI
%6 = load float, float* %1
%7 = call float @pow(float %6, i32 2)
%8 = fmul float %5, %7
store float %8, float* %2
%9 = load float, float* %2
%10 = fpext float %9 to double
%11 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([26 x i8], [26 x i8]* @.str.2, i64 0, i64 0), double %10)
ret i32 0
}

LLVM IR (-O2):
@.str.1 = [3 x i8] c"%f\00"
@M_PI = global float 0.000000e+00
@.str.2 = [26 x i8] c"Area of a circle = %5.2f\0A\00"
@str = [29 x i8] c"Enter the radius of a circle\00"
define i32 @main() {
%1 = alloca float
%2 = bitcast float* %1 to i8*
%3 = tail call i32 @puts(i8* dereferenceable(1) getelementptr inbounds ([29 x i8], [29 x i8]* @str, i64 0, i64 0))
%4 = call i32 @scanf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.1, i64 0, i64 0), float* %1)
%5 = load float, float* @M_PI
%6 = load float, float* %1
%7 = call float @pow(float %6, i32 2)
%8 = fmul float %5, %7
%9 = fpext float %8 to double
%10 = call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([26 x i8], [26 x i8]* @.str.2, i64 0, i64 0), double %9)
ret i32 0
}