double paw_Predictor_Out_F(int i, double f[]) {
  double tmp;
  tmp = 4.16666666667e-2 *
        (55.0 * f[i] - 59.0 * f[i - 1] + 37.0 * f[i - 2] - 9.0 * f[i - 3]);
  return tmp;
}


x86 assembly (clang, -O0):
<paw_Predictor_Out_F>:
push   %rbp
mov    %rsp,%rbp
mov    %edi,-0x4(%rbp)
mov    %rsi,-0x10(%rbp)
mov    -0x10(%rbp),%rax
movslq -0x4(%rbp),%rcx
movsd  (%rax,%rcx,8),%xmm1
mov    -0x10(%rbp),%rax
mov    -0x4(%rbp),%ecx
sub    $0x1,%ecx
movslq %ecx,%rcx
movsd  0xef3(%rip),%xmm0
mulsd  (%rax,%rcx,8),%xmm0
movq   %xmm0,%rax
movabs $0x8000000000000000,%rcx
xor    %rcx,%rax
movq   %rax,%xmm0
movsd  0xec7(%rip),%xmm2
mulsd  %xmm2,%xmm1
addsd  %xmm0,%xmm1
mov    -0x10(%rbp),%rax
mov    -0x4(%rbp),%ecx
sub    $0x2,%ecx
movslq %ecx,%rcx
movsd  (%rax,%rcx,8),%xmm0
movsd  0xe9d(%rip),%xmm2
mulsd  %xmm2,%xmm0
addsd  %xmm1,%xmm0
mov    -0x10(%rbp),%rax
mov    -0x4(%rbp),%ecx
sub    $0x3,%ecx
movslq %ecx,%rcx
movsd  (%rax,%rcx,8),%xmm1
movsd  0xe73(%rip),%xmm2
mulsd  %xmm2,%xmm1
addsd  %xmm0,%xmm1
movsd  0xe5b(%rip),%xmm0
mulsd  %xmm1,%xmm0
movsd  %xmm0,-0x18(%rbp)
movsd  -0x18(%rbp),%xmm0
pop    %rbp
ret

x86 assembly (clang, -O2):
<paw_Predictor_Out_F>:
movslq %edi,%rax
movsd  (%rsi,%rax,8),%xmm1
movsd  -0x8(%rsi,%rax,8),%xmm0
mulsd  0xeea(%rip),%xmm0
mulsd  0xeea(%rip),%xmm1
addsd  %xmm0,%xmm1
movsd  -0x18(%rsi,%rax,8),%xmm0
movsd  -0x10(%rsi,%rax,8),%xmm2
mulsd  0xeda(%rip),%xmm2
mulsd  0xeda(%rip),%xmm0
addsd  %xmm1,%xmm2
addsd  %xmm2,%xmm0
mulsd  0xed2(%rip),%xmm0
ret

LLVM IR (-O0):
define double @paw_Predictor_Out_F(i32 %0, double* %1) {
%3 = alloca i32
%4 = alloca double*
%5 = alloca double
store i32 %0, i32* %3
store double* %1, double** %4
%6 = load double*, double** %4
%7 = load i32, i32* %3
%8 = sext i32 %7 to i64
%9 = getelementptr inbounds double, double* %6, i64 %8
%10 = load double, double* %9
%11 = load double*, double** %4
%12 = load i32, i32* %3
%13 = sub nsw i32 %12, 1
%14 = sext i32 %13 to i64
%15 = getelementptr inbounds double, double* %11, i64 %14
%16 = load double, double* %15
%17 = fmul double 5.900000e+01, %16
%18 = fneg double %17
%19 = call double @llvm.fmuladd.f64(double 5.500000e+01, double %10, double %18)
%20 = load double*, double** %4
%21 = load i32, i32* %3
%22 = sub nsw i32 %21, 2
%23 = sext i32 %22 to i64
%24 = getelementptr inbounds double, double* %20, i64 %23
%25 = load double, double* %24
%26 = call double @llvm.fmuladd.f64(double 3.700000e+01, double %25, double %19)
%27 = load double*, double** %4
%28 = load i32, i32* %3
%29 = sub nsw i32 %28, 3
%30 = sext i32 %29 to i64
%31 = getelementptr inbounds double, double* %27, i64 %30
%32 = load double, double* %31
%33 = call double @llvm.fmuladd.f64(double -9.000000e+00, double %32, double %26)
%34 = fmul double 0x3FA5555555556819, %33
store double %34, double* %5
%35 = load double, double* %5
ret double %35
}

LLVM IR (-O2):
define double @paw_Predictor_Out_F(i32 %0, double* nocapture %1) {
%3 = sext i32 %0 to i64
%4 = getelementptr inbounds double, double* %1, i64 %3
%5 = load double, double* %4
%6 = add nsw i32 %0, -1
%7 = sext i32 %6 to i64
%8 = getelementptr inbounds double, double* %1, i64 %7
%9 = load double, double* %8
%10 = fmul double %9, -5.900000e+01
%11 = tail call double @llvm.fmuladd.f64(double %5, double 5.500000e+01, double %10)
%12 = add nsw i32 %0, -2
%13 = sext i32 %12 to i64
%14 = getelementptr inbounds double, double* %1, i64 %13
%15 = load double, double* %14
%16 = tail call double @llvm.fmuladd.f64(double %15, double 3.700000e+01, double %11)
%17 = add nsw i32 %0, -3
%18 = sext i32 %17 to i64
%19 = getelementptr inbounds double, double* %1, i64 %18
%20 = load double, double* %19
%21 = tail call double @llvm.fmuladd.f64(double %20, double -9.000000e+00, double %16)
%22 = fmul double %21, 0x3FA5555555556819
ret double %22
}