void hc_evppot(l, ratio, ppot) int l;
double ratio;
double *ppot;
{
  double c, expf1, expf2, x, xp1;
  x = (double)l;
  c = 1.0 / (2.0 * x + 1.0);
  xp1 = x + 1.0;
  expf1 = pow(ratio, x);
  expf2 = 1.0 / (expf1 * ratio);
  ppot[0] = c * (x * expf1 + xp1 * expf2);
  ppot[1] = c * (expf2 - expf1);
  ppot[2] = x * xp1 * ppot[1];
  ppot[3] = ppot[0] - ppot[1];
}


x86 assembly (clang, -O0):
<hc_evppot>:
push   %rbp
mov    %rsp,%rbp
sub    $0x40,%rsp
mov    %edi,-0x4(%rbp)
movsd  %xmm0,-0x10(%rbp)
mov    %rsi,-0x18(%rbp)
cvtsi2sdl -0x4(%rbp),%xmm0
movsd  %xmm0,-0x38(%rbp)
movsd  -0x38(%rbp),%xmm1
addsd  %xmm1,%xmm1
movsd  0xec1(%rip),%xmm0
addsd  %xmm0,%xmm1
movsd  0xeb5(%rip),%xmm0
divsd  %xmm1,%xmm0
movsd  %xmm0,-0x20(%rbp)
movsd  0xea4(%rip),%xmm0
addsd  -0x38(%rbp),%xmm0
movsd  %xmm0,-0x40(%rbp)
movsd  -0x10(%rbp),%xmm0
movsd  -0x38(%rbp),%xmm1
call   1030 <pow@plt>
movsd  %xmm0,-0x28(%rbp)
movsd  -0x28(%rbp),%xmm1
mulsd  -0x10(%rbp),%xmm1
movsd  0xe74(%rip),%xmm0
divsd  %xmm1,%xmm0
movsd  %xmm0,-0x30(%rbp)
movsd  -0x20(%rbp),%xmm0
movsd  -0x38(%rbp),%xmm1
movsd  -0x28(%rbp),%xmm3
movsd  -0x40(%rbp),%xmm2
mulsd  -0x30(%rbp),%xmm2
mulsd  %xmm3,%xmm1
addsd  %xmm2,%xmm1
mulsd  %xmm1,%xmm0
mov    -0x18(%rbp),%rax
movsd  %xmm0,(%rax)
movsd  -0x20(%rbp),%xmm0
movsd  -0x30(%rbp),%xmm1
subsd  -0x28(%rbp),%xmm1
mulsd  %xmm1,%xmm0
mov    -0x18(%rbp),%rax
movsd  %xmm0,0x8(%rax)
movsd  -0x38(%rbp),%xmm0
mulsd  -0x40(%rbp),%xmm0
mov    -0x18(%rbp),%rax
mulsd  0x8(%rax),%xmm0
mov    -0x18(%rbp),%rax
movsd  %xmm0,0x10(%rax)
mov    -0x18(%rbp),%rax
movsd  (%rax),%xmm0
mov    -0x18(%rbp),%rax
subsd  0x8(%rax),%xmm0
mov    -0x18(%rbp),%rax
movsd  %xmm0,0x18(%rax)
add    $0x40,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<hc_evppot>:
push   %rbx
sub    $0x20,%rsp
mov    %rsi,%rbx
movsd  %xmm0,(%rsp)
cvtsi2sd %edi,%xmm1
movsd  %xmm1,0x8(%rsp)
movapd %xmm1,%xmm4
addsd  %xmm1,%xmm4
movsd  0xec9(%rip),%xmm3
addsd  %xmm3,%xmm4
movapd %xmm3,%xmm2
divsd  %xmm4,%xmm2
movsd  %xmm2,0x18(%rsp)
movapd %xmm1,%xmm2
addsd  %xmm3,%xmm2
movsd  %xmm2,0x10(%rsp)
call   1030 <pow@plt>
movsd  (%rsp),%xmm1
mulsd  %xmm0,%xmm1
movsd  0xe93(%rip),%xmm5
divsd  %xmm1,%xmm5
movsd  0x10(%rsp),%xmm3
movapd %xmm3,%xmm1
mulsd  %xmm5,%xmm1
movsd  0x8(%rsp),%xmm2
mulsd  %xmm2,%xmm3
mulsd  %xmm0,%xmm2
addsd  %xmm1,%xmm2
movsd  0x18(%rsp),%xmm4
mulsd  %xmm4,%xmm2
movsd  %xmm2,(%rbx)
movapd %xmm5,%xmm1
subsd  %xmm0,%xmm1
mulsd  %xmm4,%xmm1
movsd  %xmm1,0x8(%rbx)
mulsd  %xmm1,%xmm3
movsd  %xmm3,0x10(%rbx)
subsd  %xmm1,%xmm2
movsd  %xmm2,0x18(%rbx)
add    $0x20,%rsp
pop    %rbx
ret

LLVM IR (-O0):
define void @hc_evppot(i32 %0, double %1, double* %2) {
%4 = alloca i32
%5 = alloca double
%6 = alloca double*
%7 = alloca double
%8 = alloca double
%9 = alloca double
%10 = alloca double
%11 = alloca double
store i32 %0, i32* %4
store double %1, double* %5
store double* %2, double** %6
%12 = load i32, i32* %4
%13 = sitofp i32 %12 to double
store double %13, double* %10
%14 = load double, double* %10
%15 = call double @llvm.fmuladd.f64(double 2.000000e+00, double %14, double 1.000000e+00)
%16 = fdiv double 1.000000e+00, %15
store double %16, double* %7
%17 = load double, double* %10
%18 = fadd double %17, 1.000000e+00
store double %18, double* %11
%19 = load double, double* %5
%20 = load double, double* %10
%21 = call double @pow(double %19, double %20)
store double %21, double* %8
%22 = load double, double* %8
%23 = load double, double* %5
%24 = fmul double %22, %23
%25 = fdiv double 1.000000e+00, %24
store double %25, double* %9
%26 = load double, double* %7
%27 = load double, double* %10
%28 = load double, double* %8
%29 = load double, double* %11
%30 = load double, double* %9
%31 = fmul double %29, %30
%32 = call double @llvm.fmuladd.f64(double %27, double %28, double %31)
%33 = fmul double %26, %32
%34 = load double*, double** %6
%35 = getelementptr inbounds double, double* %34, i64 0
store double %33, double* %35
%36 = load double, double* %7
%37 = load double, double* %9
%38 = load double, double* %8
%39 = fsub double %37, %38
%40 = fmul double %36, %39
%41 = load double*, double** %6
%42 = getelementptr inbounds double, double* %41, i64 1
store double %40, double* %42
%43 = load double, double* %10
%44 = load double, double* %11
%45 = fmul double %43, %44
%46 = load double*, double** %6
%47 = getelementptr inbounds double, double* %46, i64 1
%48 = load double, double* %47
%49 = fmul double %45, %48
%50 = load double*, double** %6
%51 = getelementptr inbounds double, double* %50, i64 2
store double %49, double* %51
%52 = load double*, double** %6
%53 = getelementptr inbounds double, double* %52, i64 0
%54 = load double, double* %53
%55 = load double*, double** %6
%56 = getelementptr inbounds double, double* %55, i64 1
%57 = load double, double* %56
%58 = fsub double %54, %57
%59 = load double*, double** %6
%60 = getelementptr inbounds double, double* %59, i64 3
store double %58, double* %60
ret void
}

LLVM IR (-O2):
define void @hc_evppot(i32 %0, double %1, double* nocapture %2) {
%4 = sitofp i32 %0 to double
%5 = tail call double @llvm.fmuladd.f64(double %4, double 2.000000e+00, double 1.000000e+00)
%6 = fdiv double 1.000000e+00, %5
%7 = fadd double %4, 1.000000e+00
%8 = tail call double @pow(double %1, double %4)
%9 = fmul double %8, %1
%10 = fdiv double 1.000000e+00, %9
%11 = fmul double %7, %10
%12 = tail call double @llvm.fmuladd.f64(double %4, double %8, double %11)
%13 = fmul double %6, %12
store double %13, double* %2
%14 = fsub double %10, %8
%15 = fmul double %6, %14
%16 = getelementptr inbounds double, double* %2, i64 1
store double %15, double* %16
%17 = fmul double %7, %4
%18 = fmul double %17, %15
%19 = getelementptr inbounds double, double* %2, i64 2
store double %18, double* %19
%20 = fsub double %13, %15
%21 = getelementptr inbounds double, double* %2, i64 3
store double %20, double* %21
ret void
}