#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 */
double sqrt(double);
double pdist(double *v1) {
  double ss = 0;
  ss += v1[0] * v1[0];
  ss += v1[1] * v1[1];
  ss += v1[2] * v1[2];
  return sqrt(ss);
}


x86 assembly (clang, -O0):
<pdist>:
push   %rbp
mov    %rsp,%rbp
sub    $0x10,%rsp
mov    %rdi,-0x8(%rbp)
xorps  %xmm0,%xmm0
movsd  %xmm0,-0x10(%rbp)
mov    -0x8(%rbp),%rax
movsd  (%rax),%xmm0
mov    -0x8(%rbp),%rax
movsd  (%rax),%xmm2
movsd  -0x10(%rbp),%xmm1
mulsd  %xmm2,%xmm0
addsd  %xmm1,%xmm0
movsd  %xmm0,-0x10(%rbp)
mov    -0x8(%rbp),%rax
movsd  0x8(%rax),%xmm0
mov    -0x8(%rbp),%rax
movsd  0x8(%rax),%xmm2
movsd  -0x10(%rbp),%xmm1
mulsd  %xmm2,%xmm0
addsd  %xmm1,%xmm0
movsd  %xmm0,-0x10(%rbp)
mov    -0x8(%rbp),%rax
movsd  0x10(%rax),%xmm0
mov    -0x8(%rbp),%rax
movsd  0x10(%rax),%xmm2
movsd  -0x10(%rbp),%xmm1
mulsd  %xmm2,%xmm0
addsd  %xmm1,%xmm0
movsd  %xmm0,-0x10(%rbp)
movsd  -0x10(%rbp),%xmm0
call   1030 <sqrt@plt>
add    $0x10,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<pdist>:
movsd  (%rdi),%xmm0
movsd  0x8(%rdi),%xmm1
mulsd  %xmm0,%xmm0
xorpd  %xmm2,%xmm2
addsd  %xmm2,%xmm0
mulsd  %xmm1,%xmm1
addsd  %xmm0,%xmm1
movsd  0x10(%rdi),%xmm0
mulsd  %xmm0,%xmm0
addsd  %xmm1,%xmm0
ucomisd %xmm2,%xmm0
jb     1145 <pdist+0x35>
sqrtsd %xmm0,%xmm0
ret
jmp    1030 <sqrt@plt>

LLVM IR (-O0):
define double @pdist(double* %0) {
%2 = alloca double*
%3 = alloca double
store double* %0, double** %2
store double 0.000000e+00, double* %3
%4 = load double*, double** %2
%5 = getelementptr inbounds double, double* %4, i64 0
%6 = load double, double* %5
%7 = load double*, double** %2
%8 = getelementptr inbounds double, double* %7, i64 0
%9 = load double, double* %8
%10 = load double, double* %3
%11 = call double @llvm.fmuladd.f64(double %6, double %9, double %10)
store double %11, double* %3
%12 = load double*, double** %2
%13 = getelementptr inbounds double, double* %12, i64 1
%14 = load double, double* %13
%15 = load double*, double** %2
%16 = getelementptr inbounds double, double* %15, i64 1
%17 = load double, double* %16
%18 = load double, double* %3
%19 = call double @llvm.fmuladd.f64(double %14, double %17, double %18)
store double %19, double* %3
%20 = load double*, double** %2
%21 = getelementptr inbounds double, double* %20, i64 2
%22 = load double, double* %21
%23 = load double*, double** %2
%24 = getelementptr inbounds double, double* %23, i64 2
%25 = load double, double* %24
%26 = load double, double* %3
%27 = call double @llvm.fmuladd.f64(double %22, double %25, double %26)
store double %27, double* %3
%28 = load double, double* %3
%29 = call double @sqrt(double %28)
ret double %29
}

LLVM IR (-O2):
define double @pdist(double* nocapture %0) {
%2 = load double, double* %0
%3 = tail call double @llvm.fmuladd.f64(double %2, double %2, double 0.000000e+00)
%4 = getelementptr inbounds double, double* %0, i64 1
%5 = load double, double* %4
%6 = tail call double @llvm.fmuladd.f64(double %5, double %5, double %3)
%7 = getelementptr inbounds double, double* %0, i64 2
%8 = load double, double* %7
%9 = tail call double @llvm.fmuladd.f64(double %8, double %8, double %6)
%10 = tail call double @sqrt(double %9)
ret double %10
}