#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 */
int /*<<< orphan*/ derivs_one(double *, double *, double const *);
void integrate_one_rk4(double *y, const double dt, const unsigned N,
                       const unsigned stride, const double *P, double *output) {
  unsigned i, j, k;
  double dt2, dt6;
  double y1[5], y2[5], k1[5], k2[5], k3[5], k4[5];
  dt2 = dt / 2.;
  dt6 = dt / 6.;
  for (j = 0; j < 5; j++)
    output[j] = y[j];
  for (i = 1; i < N; i++) {
    for (j = 0; j < stride; j++) {
      derivs_one(y, k1, P);
      for (k = 0; k < 5; k++)
        y1[k] = y[k] + k1[k] * dt2;
      derivs_one(y1, k2, P);
      for (k = 0; k < 5; k++)
        y2[k] = y[k] + k2[k] * dt2;
      derivs_one(y2, k3, P);
      for (k = 0; k < 5; k++)
        y2[k] = y[k] + k3[k] * dt;
      derivs_one(y2, k4, P);
      for (k = 0; k < 5; k++)
        y[k] += dt6 * (k1[k] + 2. * (k2[k] + k3[k]) + k4[k]);
    }
    for (j = 0; j < 5; j++)
      output[5 * i + j] = y[j];
  }
}


x86 assembly (clang, -O0):
<integrate_one_rk4>:
push   %rbp
mov    %rsp,%rbp
sub    $0x160,%rsp
mov    %rdi,-0x8(%rbp)
movsd  %xmm0,-0x10(%rbp)
mov    %esi,-0x14(%rbp)
mov    %edx,-0x18(%rbp)
mov    %rcx,-0x20(%rbp)
mov    %r8,-0x28(%rbp)
movsd  -0x10(%rbp),%xmm0
movsd  0xec9(%rip),%xmm1
divsd  %xmm1,%xmm0
movsd  %xmm0,-0x40(%rbp)
movsd  -0x10(%rbp),%xmm0
movsd  0xeab(%rip),%xmm1
divsd  %xmm1,%xmm0
movsd  %xmm0,-0x48(%rbp)
movl   $0x0,-0x30(%rbp)
cmpl   $0x5,-0x30(%rbp)
jae    1195 <integrate_one_rk4+0x85>
mov    -0x8(%rbp),%rax
mov    -0x30(%rbp),%ecx
movsd  (%rax,%rcx,8),%xmm0
mov    -0x28(%rbp),%rax
mov    -0x30(%rbp),%ecx
movsd  %xmm0,(%rax,%rcx,8)
mov    -0x30(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0x30(%rbp)
jmp    1165 <integrate_one_rk4+0x55>
movl   $0x1,-0x2c(%rbp)
mov    -0x2c(%rbp),%eax
cmp    -0x14(%rbp),%eax
jae    13d6 <integrate_one_rk4+0x2c6>
movl   $0x0,-0x30(%rbp)
mov    -0x30(%rbp),%eax
cmp    -0x18(%rbp),%eax
jae    1386 <integrate_one_rk4+0x276>
mov    -0x8(%rbp),%rdi
lea    -0xd0(%rbp),%rsi
mov    -0x20(%rbp),%rdx
call   1030 <derivs_one@plt>
movl   $0x0,-0x34(%rbp)
cmpl   $0x5,-0x34(%rbp)
jae    121c <integrate_one_rk4+0x10c>
mov    -0x8(%rbp),%rax
mov    -0x34(%rbp),%ecx
movsd  (%rax,%rcx,8),%xmm1
mov    -0x34(%rbp),%eax
movsd  -0xd0(%rbp,%rax,8),%xmm0
ff ff
movsd  -0x40(%rbp),%xmm2
mulsd  %xmm2,%xmm0
addsd  %xmm1,%xmm0
mov    -0x34(%rbp),%eax
movsd  %xmm0,-0x70(%rbp,%rax,8)
mov    -0x34(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0x34(%rbp)
jmp    11d6 <integrate_one_rk4+0xc6>
lea    -0x70(%rbp),%rdi
lea    -0x100(%rbp),%rsi
mov    -0x20(%rbp),%rdx
call   1030 <derivs_one@plt>
movl   $0x0,-0x34(%rbp)
cmpl   $0x5,-0x34(%rbp)
jae    1280 <integrate_one_rk4+0x170>
mov    -0x8(%rbp),%rax
mov    -0x34(%rbp),%ecx
movsd  (%rax,%rcx,8),%xmm1
mov    -0x34(%rbp),%eax
movsd  -0x100(%rbp,%rax,8),%xmm0
ff ff
movsd  -0x40(%rbp),%xmm2
mulsd  %xmm2,%xmm0
addsd  %xmm1,%xmm0
mov    -0x34(%rbp),%eax
movsd  %xmm0,-0xa0(%rbp,%rax,8)
ff ff
mov    -0x34(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0x34(%rbp)
jmp    1237 <integrate_one_rk4+0x127>
lea    -0xa0(%rbp),%rdi
lea    -0x130(%rbp),%rsi
mov    -0x20(%rbp),%rdx
call   1030 <derivs_one@plt>
movl   $0x0,-0x34(%rbp)
cmpl   $0x5,-0x34(%rbp)
jae    12e7 <integrate_one_rk4+0x1d7>
mov    -0x8(%rbp),%rax
mov    -0x34(%rbp),%ecx
movsd  (%rax,%rcx,8),%xmm1
mov    -0x34(%rbp),%eax
movsd  -0x130(%rbp,%rax,8),%xmm0
ff ff
movsd  -0x10(%rbp),%xmm2
mulsd  %xmm2,%xmm0
addsd  %xmm1,%xmm0
mov    -0x34(%rbp),%eax
movsd  %xmm0,-0xa0(%rbp,%rax,8)
ff ff
mov    -0x34(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0x34(%rbp)
jmp    129e <integrate_one_rk4+0x18e>
lea    -0xa0(%rbp),%rdi
lea    -0x160(%rbp),%rsi
mov    -0x20(%rbp),%rdx
call   1030 <derivs_one@plt>
movl   $0x0,-0x34(%rbp)
cmpl   $0x5,-0x34(%rbp)
jae    1373 <integrate_one_rk4+0x263>
movsd  -0x48(%rbp),%xmm0
mov    -0x34(%rbp),%eax
movsd  -0xd0(%rbp,%rax,8),%xmm1
ff ff
mov    -0x34(%rbp),%eax
movsd  -0x100(%rbp,%rax,8),%xmm2
ff ff
mov    -0x34(%rbp),%eax
addsd  -0x130(%rbp,%rax,8),%xmm2
ff ff
addsd  %xmm2,%xmm2
addsd  %xmm1,%xmm2
mov    -0x34(%rbp),%eax
addsd  -0x160(%rbp,%rax,8),%xmm2
ff ff
mov    -0x8(%rbp),%rax
mov    -0x34(%rbp),%ecx
movsd  (%rax,%rcx,8),%xmm1
mulsd  %xmm2,%xmm0
addsd  %xmm1,%xmm0
movsd  %xmm0,(%rax,%rcx,8)
mov    -0x34(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0x34(%rbp)
jmp    1305 <integrate_one_rk4+0x1f5>
jmp    1378 <integrate_one_rk4+0x268>
mov    -0x30(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0x30(%rbp)
jmp    11af <integrate_one_rk4+0x9f>
movl   $0x0,-0x30(%rbp)
cmpl   $0x5,-0x30(%rbp)
jae    13c3 <integrate_one_rk4+0x2b3>
mov    -0x8(%rbp),%rax
mov    -0x30(%rbp),%ecx
movsd  (%rax,%rcx,8),%xmm0
mov    -0x28(%rbp),%rax
imul   $0x5,-0x2c(%rbp),%ecx
add    -0x30(%rbp),%ecx
mov    %ecx,%ecx
movsd  %xmm0,(%rax,%rcx,8)
mov    -0x30(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0x30(%rbp)
jmp    138d <integrate_one_rk4+0x27d>
jmp    13c8 <integrate_one_rk4+0x2b8>
mov    -0x2c(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0x2c(%rbp)
jmp    119c <integrate_one_rk4+0x8c>
add    $0x160,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<integrate_one_rk4>:
push   %rbp
push   %r15
push   %r14
push   %r13
push   %r12
push   %rbx
sub    $0x198,%rsp
mov    %edx,0x4(%rsp)
movapd %xmm0,%xmm1
movsd  (%rdi),%xmm0
movsd  %xmm0,(%r8)
movsd  0x8(%rdi),%xmm0
movsd  %xmm0,0x8(%r8)
movsd  0x10(%rdi),%xmm0
movsd  %xmm0,0x10(%r8)
movsd  0x18(%rdi),%xmm0
movsd  %xmm0,0x18(%r8)
movsd  0x20(%rdi),%xmm0
mov    %r8,0x18(%rsp)
movsd  %xmm0,0x20(%r8)
cmp    $0x2,%esi
jb     148d <integrate_one_rk4+0x37d>
mov    %rcx,%rbx
mov    %rdi,%rbp
movsd  0xe86(%rip),%xmm2
movapd %xmm1,%xmm3
divsd  0xe82(%rip),%xmm3
mulsd  %xmm1,%xmm2
mov    %esi,%eax
mov    %rax,0x10(%rsp)
movapd %xmm2,%xmm4
unpcklpd %xmm2,%xmm4
movapd %xmm1,%xmm5
unpcklpd %xmm1,%xmm5
movapd %xmm3,%xmm6
unpcklpd %xmm3,%xmm6
mov    $0x1,%edx
lea    0xa0(%rsp),%r13
lea    0x170(%rsp),%r15
lea    0xd0(%rsp),%r14
movapd %xmm3,0x130(%rsp)
movapd %xmm6,0x120(%rsp)
movapd %xmm4,0x30(%rsp)
movapd %xmm5,0x110(%rsp)
movapd %xmm1,0x100(%rsp)
movapd %xmm2,0x20(%rsp)
jmp    1260 <integrate_one_rk4+0x150>
nopl   0x0(%rax,%rax,1)
movsd  0x0(%rbp),%xmm0
mov    0x8(%rsp),%rdx
lea    (%rdx,%rdx,4),%eax
mov    0x18(%rsp),%rcx
movsd  %xmm0,(%rcx,%rax,8)
movsd  0x8(%rbp),%xmm0
lea    0x1(%rdx,%rdx,4),%eax
movsd  %xmm0,(%rcx,%rax,8)
movsd  0x10(%rbp),%xmm0
lea    0x2(%rdx,%rdx,4),%eax
movsd  %xmm0,(%rcx,%rax,8)
movsd  0x18(%rbp),%xmm0
lea    0x3(%rdx,%rdx,4),%eax
movsd  %xmm0,(%rcx,%rax,8)
movsd  0x20(%rbp),%xmm0
lea    (%rdx,%rdx,4),%eax
add    $0x4,%eax
movsd  %xmm0,(%rcx,%rax,8)
add    $0x1,%rdx
cmp    0x10(%rsp),%rdx
je     148d <integrate_one_rk4+0x37d>
mov    %rdx,0x8(%rsp)
mov    0x4(%rsp),%eax
mov    %eax,%r12d
test   %eax,%eax
je     1200 <integrate_one_rk4+0xf0>
mov    %rbp,%rdi
mov    %r13,%rsi
mov    %rbx,%rdx
call   1030 <derivs_one@plt>
movupd 0x0(%rbp),%xmm0
movapd 0xa0(%rsp),%xmm1
movapd 0x30(%rsp),%xmm2
mulpd  %xmm2,%xmm1
addpd  %xmm0,%xmm1
movapd %xmm1,0x170(%rsp)
movupd 0x10(%rbp),%xmm0
movapd 0xb0(%rsp),%xmm1
mulpd  %xmm2,%xmm1
addpd  %xmm0,%xmm1
movapd %xmm1,0x180(%rsp)
movsd  0xc0(%rsp),%xmm0
mulsd  0x20(%rsp),%xmm0
addsd  0x20(%rbp),%xmm0
movsd  %xmm0,0x190(%rsp)
mov    %r15,%rdi
lea    0x70(%rsp),%rsi
mov    %rbx,%rdx
call   1030 <derivs_one@plt>
movupd 0x0(%rbp),%xmm0
movapd 0x70(%rsp),%xmm1
movapd 0x30(%rsp),%xmm2
mulpd  %xmm2,%xmm1
addpd  %xmm0,%xmm1
movapd %xmm1,0xd0(%rsp)
movupd 0x10(%rbp),%xmm0
movapd 0x80(%rsp),%xmm1
mulpd  %xmm2,%xmm1
addpd  %xmm0,%xmm1
movapd %xmm1,0xe0(%rsp)
movsd  0x90(%rsp),%xmm0
mulsd  0x20(%rsp),%xmm0
addsd  0x20(%rbp),%xmm0
movsd  %xmm0,0xf0(%rsp)
mov    %r14,%rdi
lea    0x40(%rsp),%rsi
mov    %rbx,%rdx
call   1030 <derivs_one@plt>
movupd 0x0(%rbp),%xmm0
movapd 0x40(%rsp),%xmm1
movapd 0x110(%rsp),%xmm2
mulpd  %xmm2,%xmm1
addpd  %xmm0,%xmm1
movapd %xmm1,0xd0(%rsp)
movupd 0x10(%rbp),%xmm0
movapd 0x50(%rsp),%xmm1
mulpd  %xmm2,%xmm1
addpd  %xmm0,%xmm1
movapd %xmm1,0xe0(%rsp)
movsd  0x60(%rsp),%xmm0
mulsd  0x100(%rsp),%xmm0
addsd  0x20(%rbp),%xmm0
movsd  %xmm0,0xf0(%rsp)
mov    %r14,%rdi
lea    0x140(%rsp),%rsi
mov    %rbx,%rdx
call   1030 <derivs_one@plt>
movapd 0x120(%rsp),%xmm6
movapd 0x130(%rsp),%xmm3
movapd 0x70(%rsp),%xmm1
addpd  0x40(%rsp),%xmm1
addpd  %xmm1,%xmm1
addpd  0xa0(%rsp),%xmm1
addpd  0x140(%rsp),%xmm1
mulpd  %xmm6,%xmm1
movupd 0x0(%rbp),%xmm0
addpd  %xmm1,%xmm0
movupd 0x10(%rbp),%xmm1
movupd %xmm0,0x0(%rbp)
movapd 0x80(%rsp),%xmm2
addpd  0x50(%rsp),%xmm2
addpd  %xmm2,%xmm2
addpd  0xb0(%rsp),%xmm2
addpd  0x150(%rsp),%xmm2
mulpd  %xmm6,%xmm2
addpd  %xmm1,%xmm2
movupd %xmm2,0x10(%rbp)
movsd  0x90(%rsp),%xmm1
addsd  0x60(%rsp),%xmm1
addsd  %xmm1,%xmm1
addsd  0xc0(%rsp),%xmm1
addsd  0x160(%rsp),%xmm1
mulsd  %xmm3,%xmm1
addsd  0x20(%rbp),%xmm1
movsd  %xmm1,0x20(%rbp)
add    $0xffffffff,%r12d
jne    1270 <integrate_one_rk4+0x160>
jmp    1205 <integrate_one_rk4+0xf5>
add    $0x198,%rsp
pop    %rbx
pop    %r12
pop    %r13
pop    %r14
pop    %r15
pop    %rbp
ret

LLVM IR (-O0):
define void @integrate_one_rk4(double* %0, double %1, i32 %2, i32 %3, double* %4, double* %5) {
%7 = alloca double*
%8 = alloca double
%9 = alloca i32
%10 = alloca i32
%11 = alloca double*
%12 = alloca double*
%13 = alloca i32
%14 = alloca i32
%15 = alloca i32
%16 = alloca double
%17 = alloca double
%18 = alloca [5 x double]
%19 = alloca [5 x double]
%20 = alloca [5 x double]
%21 = alloca [5 x double]
%22 = alloca [5 x double]
%23 = alloca [5 x double]
store double* %0, double** %7
store double %1, double* %8
store i32 %2, i32* %9
store i32 %3, i32* %10
store double* %4, double** %11
store double* %5, double** %12
%24 = load double, double* %8
%25 = fdiv double %24, 2.000000e+00
store double %25, double* %16
%26 = load double, double* %8
%27 = fdiv double %26, 6.000000e+00
store double %27, double* %17
store i32 0, i32* %14
br label %28
28: ; preds = %41, %6
%29 = load i32, i32* %14
%30 = icmp ult i32 %29, 5
br i1 %30, label %31, label %44
31: ; preds = %28
%32 = load double*, double** %7
%33 = load i32, i32* %14
%34 = zext i32 %33 to i64
%35 = getelementptr inbounds double, double* %32, i64 %34
%36 = load double, double* %35
%37 = load double*, double** %12
%38 = load i32, i32* %14
%39 = zext i32 %38 to i64
%40 = getelementptr inbounds double, double* %37, i64 %39
store double %36, double* %40
br label %41
41: ; preds = %31
%42 = load i32, i32* %14
%43 = add i32 %42, 1
store i32 %43, i32* %14
br label %28
44: ; preds = %28
store i32 1, i32* %13
br label %45
45: ; preds = %195, %44
%46 = load i32, i32* %13
%47 = load i32, i32* %9
%48 = icmp ult i32 %46, %47
br i1 %48, label %49, label %198
49: ; preds = %45
store i32 0, i32* %14
br label %50
50: ; preds = %171, %49
%51 = load i32, i32* %14
%52 = load i32, i32* %10
%53 = icmp ult i32 %51, %52
br i1 %53, label %54, label %174
54: ; preds = %50
%55 = load double*, double** %7
%56 = getelementptr inbounds [5 x double], [5 x double]* %20, i64 0, i64 0
%57 = load double*, double** %11
%58 = call i32 @derivs_one(double* %55, double* %56, double* %57)
store i32 0, i32* %15
br label %59
59: ; preds = %77, %54
%60 = load i32, i32* %15
%61 = icmp ult i32 %60, 5
br i1 %61, label %62, label %80
62: ; preds = %59
%63 = load double*, double** %7
%64 = load i32, i32* %15
%65 = zext i32 %64 to i64
%66 = getelementptr inbounds double, double* %63, i64 %65
%67 = load double, double* %66
%68 = load i32, i32* %15
%69 = zext i32 %68 to i64
%70 = getelementptr inbounds [5 x double], [5 x double]* %20, i64 0, i64 %69
%71 = load double, double* %70
%72 = load double, double* %16
%73 = call double @llvm.fmuladd.f64(double %71, double %72, double %67)
%74 = load i32, i32* %15
%75 = zext i32 %74 to i64
%76 = getelementptr inbounds [5 x double], [5 x double]* %18, i64 0, i64 %75
store double %73, double* %76
br label %77
77: ; preds = %62
%78 = load i32, i32* %15
%79 = add i32 %78, 1
store i32 %79, i32* %15
br label %59
80: ; preds = %59
%81 = getelementptr inbounds [5 x double], [5 x double]* %18, i64 0, i64 0
%82 = getelementptr inbounds [5 x double], [5 x double]* %21, i64 0, i64 0
%83 = load double*, double** %11
%84 = call i32 @derivs_one(double* %81, double* %82, double* %83)
store i32 0, i32* %15
br label %85
85: ; preds = %103, %80
%86 = load i32, i32* %15
%87 = icmp ult i32 %86, 5
br i1 %87, label %88, label %106
88: ; preds = %85
%89 = load double*, double** %7
%90 = load i32, i32* %15
%91 = zext i32 %90 to i64
%92 = getelementptr inbounds double, double* %89, i64 %91
%93 = load double, double* %92
%94 = load i32, i32* %15
%95 = zext i32 %94 to i64
%96 = getelementptr inbounds [5 x double], [5 x double]* %21, i64 0, i64 %95
%97 = load double, double* %96
%98 = load double, double* %16
%99 = call double @llvm.fmuladd.f64(double %97, double %98, double %93)
%100 = load i32, i32* %15
%101 = zext i32 %100 to i64
%102 = getelementptr inbounds [5 x double], [5 x double]* %19, i64 0, i64 %101
store double %99, double* %102
br label %103
103: ; preds = %88
%104 = load i32, i32* %15
%105 = add i32 %104, 1
store i32 %105, i32* %15
br label %85
106: ; preds = %85
%107 = getelementptr inbounds [5 x double], [5 x double]* %19, i64 0, i64 0
%108 = getelementptr inbounds [5 x double], [5 x double]* %22, i64 0, i64 0
%109 = load double*, double** %11
%110 = call i32 @derivs_one(double* %107, double* %108, double* %109)
store i32 0, i32* %15
br label %111
111: ; preds = %129, %106
%112 = load i32, i32* %15
%113 = icmp ult i32 %112, 5
br i1 %113, label %114, label %132
114: ; preds = %111
%115 = load double*, double** %7
%116 = load i32, i32* %15
%117 = zext i32 %116 to i64
%118 = getelementptr inbounds double, double* %115, i64 %117
%119 = load double, double* %118
%120 = load i32, i32* %15
%121 = zext i32 %120 to i64
%122 = getelementptr inbounds [5 x double], [5 x double]* %22, i64 0, i64 %121
%123 = load double, double* %122
%124 = load double, double* %8
%125 = call double @llvm.fmuladd.f64(double %123, double %124, double %119)
%126 = load i32, i32* %15
%127 = zext i32 %126 to i64
%128 = getelementptr inbounds [5 x double], [5 x double]* %19, i64 0, i64 %127
store double %125, double* %128
br label %129
129: ; preds = %114
%130 = load i32, i32* %15
%131 = add i32 %130, 1
store i32 %131, i32* %15
br label %111
132: ; preds = %111
%133 = getelementptr inbounds [5 x double], [5 x double]* %19, i64 0, i64 0
%134 = getelementptr inbounds [5 x double], [5 x double]* %23, i64 0, i64 0
%135 = load double*, double** %11
%136 = call i32 @derivs_one(double* %133, double* %134, double* %135)
store i32 0, i32* %15
br label %137
137: ; preds = %167, %132
%138 = load i32, i32* %15
%139 = icmp ult i32 %138, 5
br i1 %139, label %140, label %170
140: ; preds = %137
%141 = load double, double* %17
%142 = load i32, i32* %15
%143 = zext i32 %142 to i64
%144 = getelementptr inbounds [5 x double], [5 x double]* %20, i64 0, i64 %143
%145 = load double, double* %144
%146 = load i32, i32* %15
%147 = zext i32 %146 to i64
%148 = getelementptr inbounds [5 x double], [5 x double]* %21, i64 0, i64 %147
%149 = load double, double* %148
%150 = load i32, i32* %15
%151 = zext i32 %150 to i64
%152 = getelementptr inbounds [5 x double], [5 x double]* %22, i64 0, i64 %151
%153 = load double, double* %152
%154 = fadd double %149, %153
%155 = call double @llvm.fmuladd.f64(double 2.000000e+00, double %154, double %145)
%156 = load i32, i32* %15
%157 = zext i32 %156 to i64
%158 = getelementptr inbounds [5 x double], [5 x double]* %23, i64 0, i64 %157
%159 = load double, double* %158
%160 = fadd double %155, %159
%161 = load double*, double** %7
%162 = load i32, i32* %15
%163 = zext i32 %162 to i64
%164 = getelementptr inbounds double, double* %161, i64 %163
%165 = load double, double* %164
%166 = call double @llvm.fmuladd.f64(double %141, double %160, double %165)
store double %166, double* %164
br label %167
167: ; preds = %140
%168 = load i32, i32* %15
%169 = add i32 %168, 1
store i32 %169, i32* %15
br label %137
170: ; preds = %137
br label %171
171: ; preds = %170
%172 = load i32, i32* %14
%173 = add i32 %172, 1
store i32 %173, i32* %14
br label %50
174: ; preds = %50
store i32 0, i32* %14
br label %175
175: ; preds = %191, %174
%176 = load i32, i32* %14
%177 = icmp ult i32 %176, 5
br i1 %177, label %178, label %194
178: ; preds = %175
%179 = load double*, double** %7
%180 = load i32, i32* %14
%181 = zext i32 %180 to i64
%182 = getelementptr inbounds double, double* %179, i64 %181
%183 = load double, double* %182
%184 = load double*, double** %12
%185 = load i32, i32* %13
%186 = mul i32 5, %185
%187 = load i32, i32* %14
%188 = add i32 %186, %187
%189 = zext i32 %188 to i64
%190 = getelementptr inbounds double, double* %184, i64 %189
store double %183, double* %190
br label %191
191: ; preds = %178
%192 = load i32, i32* %14
%193 = add i32 %192, 1
store i32 %193, i32* %14
br label %175
194: ; preds = %175
br label %195
195: ; preds = %194
%196 = load i32, i32* %13
%197 = add i32 %196, 1
store i32 %197, i32* %13
br label %45
198: ; preds = %45
ret void
}

LLVM IR (-O2):
define void @integrate_one_rk4(double* %0, double %1, i32 %2, i32 %3, double* %4, double* nocapture writeonly %5) {
%7 = alloca [5 x double]
%8 = alloca [5 x double]
%9 = alloca [5 x double]
%10 = alloca [5 x double]
%11 = alloca [5 x double]
%12 = alloca [5 x double]
%13 = bitcast [5 x double]* %7 to i8*
%14 = bitcast [5 x double]* %8 to i8*
%15 = bitcast [5 x double]* %9 to i8*
%16 = bitcast [5 x double]* %10 to i8*
%17 = bitcast [5 x double]* %11 to i8*
%18 = bitcast [5 x double]* %12 to i8*
%19 = fmul double %1, 5.000000e-01
%20 = load double, double* %0
store double %20, double* %5
%21 = getelementptr inbounds double, double* %0, i64 1
%22 = load double, double* %21
%23 = getelementptr inbounds double, double* %5, i64 1
store double %22, double* %23
%24 = getelementptr inbounds double, double* %0, i64 2
%25 = load double, double* %24
%26 = getelementptr inbounds double, double* %5, i64 2
store double %25, double* %26
%27 = getelementptr inbounds double, double* %0, i64 3
%28 = load double, double* %27
%29 = getelementptr inbounds double, double* %5, i64 3
store double %28, double* %29
%30 = getelementptr inbounds double, double* %0, i64 4
%31 = load double, double* %30
%32 = getelementptr inbounds double, double* %5, i64 4
store double %31, double* %32
%33 = fdiv double %1, 6.000000e+00
%34 = icmp ugt i32 %2, 1
br i1 %34, label %35, label %184
35: ; preds = %6
%36 = icmp eq i32 %3, 0
%37 = getelementptr inbounds [5 x double], [5 x double]* %9, i64 0, i64 0
%38 = getelementptr inbounds [5 x double], [5 x double]* %7, i64 0, i64 0
%39 = getelementptr inbounds [5 x double], [5 x double]* %10, i64 0, i64 0
%40 = getelementptr inbounds [5 x double], [5 x double]* %8, i64 0, i64 0
%41 = getelementptr inbounds [5 x double], [5 x double]* %11, i64 0, i64 0
%42 = getelementptr inbounds [5 x double], [5 x double]* %12, i64 0, i64 0
%43 = zext i32 %2 to i64
%44 = getelementptr inbounds [5 x double], [5 x double]* %9, i64 0, i64 2
%45 = getelementptr inbounds [5 x double], [5 x double]* %7, i64 0, i64 2
%46 = getelementptr inbounds [5 x double], [5 x double]* %9, i64 0, i64 4
%47 = getelementptr inbounds [5 x double], [5 x double]* %7, i64 0, i64 4
%48 = getelementptr inbounds [5 x double], [5 x double]* %10, i64 0, i64 2
%49 = getelementptr inbounds [5 x double], [5 x double]* %8, i64 0, i64 2
%50 = getelementptr inbounds [5 x double], [5 x double]* %10, i64 0, i64 4
%51 = getelementptr inbounds [5 x double], [5 x double]* %8, i64 0, i64 4
%52 = getelementptr inbounds [5 x double], [5 x double]* %11, i64 0, i64 2
%53 = getelementptr inbounds [5 x double], [5 x double]* %11, i64 0, i64 4
%54 = getelementptr inbounds [5 x double], [5 x double]* %12, i64 0, i64 2
%55 = getelementptr inbounds [5 x double], [5 x double]* %12, i64 0, i64 4
%56 = bitcast double* %0 to <2 x double>*
%57 = bitcast [5 x double]* %9 to <2 x double>*
%58 = insertelement <2 x double> poison, double %19, i64 0
%59 = shufflevector <2 x double> %58, <2 x double> poison, <2 x i32> zeroinitializer
%60 = bitcast [5 x double]* %7 to <2 x double>*
%61 = bitcast double* %24 to <2 x double>*
%62 = bitcast double* %44 to <2 x double>*
%63 = bitcast double* %45 to <2 x double>*
%64 = bitcast double* %0 to <2 x double>*
%65 = bitcast [5 x double]* %10 to <2 x double>*
%66 = bitcast [5 x double]* %8 to <2 x double>*
%67 = bitcast double* %24 to <2 x double>*
%68 = bitcast double* %48 to <2 x double>*
%69 = bitcast double* %49 to <2 x double>*
%70 = bitcast double* %0 to <2 x double>*
%71 = bitcast [5 x double]* %11 to <2 x double>*
%72 = insertelement <2 x double> poison, double %1, i64 0
%73 = shufflevector <2 x double> %72, <2 x double> poison, <2 x i32> zeroinitializer
%74 = bitcast [5 x double]* %8 to <2 x double>*
%75 = bitcast double* %24 to <2 x double>*
%76 = bitcast double* %52 to <2 x double>*
%77 = bitcast double* %49 to <2 x double>*
%78 = bitcast [5 x double]* %9 to <2 x double>*
%79 = bitcast [5 x double]* %10 to <2 x double>*
%80 = bitcast [5 x double]* %11 to <2 x double>*
%81 = bitcast [5 x double]* %12 to <2 x double>*
%82 = bitcast double* %0 to <2 x double>*
%83 = insertelement <2 x double> poison, double %33, i64 0
%84 = shufflevector <2 x double> %83, <2 x double> poison, <2 x i32> zeroinitializer
%85 = bitcast double* %0 to <2 x double>*
%86 = bitcast double* %44 to <2 x double>*
%87 = bitcast double* %48 to <2 x double>*
%88 = bitcast double* %52 to <2 x double>*
%89 = bitcast double* %54 to <2 x double>*
%90 = bitcast double* %24 to <2 x double>*
%91 = bitcast double* %24 to <2 x double>*
br label %92
92: ; preds = %35, %98
%93 = phi i64 [ 1, %35 ], [ %120, %98 ]
br i1 %36, label %94, label %122
94: ; preds = %92
%95 = load double, double* %0
br label %98
96: ; preds = %122
%97 = extractelement <2 x double> %163, i64 0
br label %98
98: ; preds = %96, %94
%99 = phi double [ %95, %94 ], [ %97, %96 ]
%100 = trunc i64 %93 to i32
%101 = mul i32 %100, 5
%102 = zext i32 %101 to i64
%103 = getelementptr inbounds double, double* %5, i64 %102
store double %99, double* %103
%104 = load double, double* %21
%105 = add i32 %101, 1
%106 = zext i32 %105 to i64
%107 = getelementptr inbounds double, double* %5, i64 %106
store double %104, double* %107
%108 = load double, double* %24
%109 = add i32 %101, 2
%110 = zext i32 %109 to i64
%111 = getelementptr inbounds double, double* %5, i64 %110
store double %108, double* %111
%112 = load double, double* %27
%113 = add i32 %101, 3
%114 = zext i32 %113 to i64
%115 = getelementptr inbounds double, double* %5, i64 %114
store double %112, double* %115
%116 = load double, double* %30
%117 = add i32 %101, 4
%118 = zext i32 %117 to i64
%119 = getelementptr inbounds double, double* %5, i64 %118
store double %116, double* %119
%120 = add nuw nsw i64 %93, 1
%121 = icmp eq i64 %120, %43
br i1 %121, label %184, label %92
122: ; preds = %92, %122
%123 = phi i32 [ %182, %122 ], [ 0, %92 ]
%124 = call i32 @derivs_one(double* %0, double* %37, double* %4)
%125 = load <2 x double>, <2 x double>* %56
%126 = load <2 x double>, <2 x double>* %57
%127 = call <2 x double> @llvm.fmuladd.v2f64(<2 x double> %126, <2 x double> %59, <2 x double> %125)
store <2 x double> %127, <2 x double>* %60
%128 = load <2 x double>, <2 x double>* %61
%129 = load <2 x double>, <2 x double>* %62
%130 = call <2 x double> @llvm.fmuladd.v2f64(<2 x double> %129, <2 x double> %59, <2 x double> %128)
store <2 x double> %130, <2 x double>* %63
%131 = load double, double* %30
%132 = load double, double* %46
%133 = call double @llvm.fmuladd.f64(double %132, double %19, double %131)
store double %133, double* %47
%134 = call i32 @derivs_one(double* %38, double* %39, double* %4)
%135 = load <2 x double>, <2 x double>* %64
%136 = load <2 x double>, <2 x double>* %65
%137 = call <2 x double> @llvm.fmuladd.v2f64(<2 x double> %136, <2 x double> %59, <2 x double> %135)
store <2 x double> %137, <2 x double>* %66
%138 = load <2 x double>, <2 x double>* %67
%139 = load <2 x double>, <2 x double>* %68
%140 = call <2 x double> @llvm.fmuladd.v2f64(<2 x double> %139, <2 x double> %59, <2 x double> %138)
store <2 x double> %140, <2 x double>* %69
%141 = load double, double* %30
%142 = load double, double* %50
%143 = call double @llvm.fmuladd.f64(double %142, double %19, double %141)
store double %143, double* %51
%144 = call i32 @derivs_one(double* %40, double* %41, double* %4)
%145 = load <2 x double>, <2 x double>* %70
%146 = load <2 x double>, <2 x double>* %71
%147 = call <2 x double> @llvm.fmuladd.v2f64(<2 x double> %146, <2 x double> %73, <2 x double> %145)
store <2 x double> %147, <2 x double>* %74
%148 = load <2 x double>, <2 x double>* %75
%149 = load <2 x double>, <2 x double>* %76
%150 = call <2 x double> @llvm.fmuladd.v2f64(<2 x double> %149, <2 x double> %73, <2 x double> %148)
store <2 x double> %150, <2 x double>* %77
%151 = load double, double* %30
%152 = load double, double* %53
%153 = call double @llvm.fmuladd.f64(double %152, double %1, double %151)
store double %153, double* %51
%154 = call i32 @derivs_one(double* %40, double* %42, double* %4)
%155 = load <2 x double>, <2 x double>* %78
%156 = load <2 x double>, <2 x double>* %79
%157 = load <2 x double>, <2 x double>* %80
%158 = fadd <2 x double> %156, %157
%159 = call <2 x double> @llvm.fmuladd.v2f64(<2 x double> %158, <2 x double> <double 2.000000e+00, double 2.000000e+00>, <2 x double> %155)
%160 = load <2 x double>, <2 x double>* %81
%161 = fadd <2 x double> %160, %159
%162 = load <2 x double>, <2 x double>* %82
%163 = call <2 x double> @llvm.fmuladd.v2f64(<2 x double> %84, <2 x double> %161, <2 x double> %162)
store <2 x double> %163, <2 x double>* %85
%164 = load <2 x double>, <2 x double>* %86
%165 = load <2 x double>, <2 x double>* %87
%166 = load <2 x double>, <2 x double>* %88
%167 = fadd <2 x double> %165, %166
%168 = call <2 x double> @llvm.fmuladd.v2f64(<2 x double> %167, <2 x double> <double 2.000000e+00, double 2.000000e+00>, <2 x double> %164)
%169 = load <2 x double>, <2 x double>* %89
%170 = fadd <2 x double> %169, %168
%171 = load <2 x double>, <2 x double>* %90
%172 = call <2 x double> @llvm.fmuladd.v2f64(<2 x double> %84, <2 x double> %170, <2 x double> %171)
store <2 x double> %172, <2 x double>* %91
%173 = load double, double* %46
%174 = load double, double* %50
%175 = load double, double* %53
%176 = fadd double %174, %175
%177 = call double @llvm.fmuladd.f64(double %176, double 2.000000e+00, double %173)
%178 = load double, double* %55
%179 = fadd double %178, %177
%180 = load double, double* %30
%181 = call double @llvm.fmuladd.f64(double %33, double %179, double %180)
store double %181, double* %30
%182 = add nuw i32 %123, 1
%183 = icmp eq i32 %182, %3
br i1 %183, label %96, label %122
184: ; preds = %98, %6
ret void
}