void inverse_transform44d3f(double *m1, float *m2, float *m3) {
  register double m2r0 = m2[0] - m1[3];
  register double m2r1 = m2[1] - m1[7];
  register double m2r2 = m2[2] - m1[11];
  m3[0] = (float)(m1[0] * m2r0 + m1[4] * m2r1 + m1[8] * m2r2);
  m3[1] = (float)(m1[1] * m2r0 + m1[5] * m2r1 + m1[9] * m2r2);
  m3[2] = (float)(m1[2] * m2r0 + m1[6] * m2r1 + m1[10] * m2r2);
}


x86 assembly (clang, -O0):
<inverse_transform44d3f>:
push   %rbp
mov    %rsp,%rbp
mov    %rdi,-0x8(%rbp)
mov    %rsi,-0x10(%rbp)
mov    %rdx,-0x18(%rbp)
mov    -0x10(%rbp),%rax
movss  (%rax),%xmm0
cvtss2sd %xmm0,%xmm0
mov    -0x8(%rbp),%rax
subsd  0x18(%rax),%xmm0
movsd  %xmm0,-0x20(%rbp)
mov    -0x10(%rbp),%rax
movss  0x4(%rax),%xmm0
cvtss2sd %xmm0,%xmm0
mov    -0x8(%rbp),%rax
subsd  0x38(%rax),%xmm0
movsd  %xmm0,-0x28(%rbp)
mov    -0x10(%rbp),%rax
movss  0x8(%rax),%xmm0
cvtss2sd %xmm0,%xmm0
mov    -0x8(%rbp),%rax
subsd  0x58(%rax),%xmm0
movsd  %xmm0,-0x30(%rbp)
mov    -0x8(%rbp),%rax
movsd  (%rax),%xmm1
movsd  -0x20(%rbp),%xmm2
mov    -0x8(%rbp),%rax
movsd  0x20(%rax),%xmm0
mulsd  -0x28(%rbp),%xmm0
mulsd  %xmm2,%xmm1
addsd  %xmm0,%xmm1
mov    -0x8(%rbp),%rax
movsd  0x40(%rax),%xmm0
movsd  -0x30(%rbp),%xmm2
mulsd  %xmm2,%xmm0
addsd  %xmm1,%xmm0
cvtsd2ss %xmm0,%xmm0
mov    -0x18(%rbp),%rax
movss  %xmm0,(%rax)
mov    -0x8(%rbp),%rax
movsd  0x8(%rax),%xmm1
movsd  -0x20(%rbp),%xmm2
mov    -0x8(%rbp),%rax
movsd  0x28(%rax),%xmm0
mulsd  -0x28(%rbp),%xmm0
mulsd  %xmm2,%xmm1
addsd  %xmm0,%xmm1
mov    -0x8(%rbp),%rax
movsd  0x48(%rax),%xmm0
movsd  -0x30(%rbp),%xmm2
mulsd  %xmm2,%xmm0
addsd  %xmm1,%xmm0
cvtsd2ss %xmm0,%xmm0
mov    -0x18(%rbp),%rax
movss  %xmm0,0x4(%rax)
mov    -0x8(%rbp),%rax
movsd  0x10(%rax),%xmm1
movsd  -0x20(%rbp),%xmm2
mov    -0x8(%rbp),%rax
movsd  0x30(%rax),%xmm0
mulsd  -0x28(%rbp),%xmm0
mulsd  %xmm2,%xmm1
addsd  %xmm0,%xmm1
mov    -0x8(%rbp),%rax
movsd  0x50(%rax),%xmm0
movsd  -0x30(%rbp),%xmm2
mulsd  %xmm2,%xmm0
addsd  %xmm1,%xmm0
cvtsd2ss %xmm0,%xmm0
mov    -0x18(%rbp),%rax
movss  %xmm0,0x8(%rax)
pop    %rbp
ret

x86 assembly (clang, -O2):
<inverse_transform44d3f>:
movss  (%rsi),%xmm0
movss  0x4(%rsi),%xmm1
cvtss2sd %xmm0,%xmm0
subsd  0x18(%rdi),%xmm0
cvtss2sd %xmm1,%xmm2
subsd  0x38(%rdi),%xmm2
movss  0x8(%rsi),%xmm1
cvtss2sd %xmm1,%xmm1
subsd  0x58(%rdi),%xmm1
movsd  0x20(%rdi),%xmm3
mulsd  %xmm2,%xmm3
movsd  (%rdi),%xmm4
mulsd  %xmm0,%xmm4
addsd  %xmm3,%xmm4
movsd  0x40(%rdi),%xmm3
mulsd  %xmm1,%xmm3
addsd  %xmm4,%xmm3
cvtsd2ss %xmm3,%xmm3
movss  %xmm3,(%rdx)
movsd  0x28(%rdi),%xmm3
mulsd  %xmm2,%xmm3
movsd  0x8(%rdi),%xmm4
mulsd  %xmm0,%xmm4
addsd  %xmm3,%xmm4
movsd  0x48(%rdi),%xmm3
mulsd  %xmm1,%xmm3
addsd  %xmm4,%xmm3
cvtsd2ss %xmm3,%xmm3
movss  %xmm3,0x4(%rdx)
mulsd  0x30(%rdi),%xmm2
mulsd  0x10(%rdi),%xmm0
addsd  %xmm2,%xmm0
mulsd  0x50(%rdi),%xmm1
addsd  %xmm0,%xmm1
xorps  %xmm0,%xmm0
cvtsd2ss %xmm1,%xmm0
movss  %xmm0,0x8(%rdx)
ret

LLVM IR (-O0):
define void @inverse_transform44d3f(double* %0, float* %1, float* %2) {
%4 = alloca double*
%5 = alloca float*
%6 = alloca float*
%7 = alloca double
%8 = alloca double
%9 = alloca double
store double* %0, double** %4
store float* %1, float** %5
store float* %2, float** %6
%10 = load float*, float** %5
%11 = getelementptr inbounds float, float* %10, i64 0
%12 = load float, float* %11
%13 = fpext float %12 to double
%14 = load double*, double** %4
%15 = getelementptr inbounds double, double* %14, i64 3
%16 = load double, double* %15
%17 = fsub double %13, %16
store double %17, double* %7
%18 = load float*, float** %5
%19 = getelementptr inbounds float, float* %18, i64 1
%20 = load float, float* %19
%21 = fpext float %20 to double
%22 = load double*, double** %4
%23 = getelementptr inbounds double, double* %22, i64 7
%24 = load double, double* %23
%25 = fsub double %21, %24
store double %25, double* %8
%26 = load float*, float** %5
%27 = getelementptr inbounds float, float* %26, i64 2
%28 = load float, float* %27
%29 = fpext float %28 to double
%30 = load double*, double** %4
%31 = getelementptr inbounds double, double* %30, i64 11
%32 = load double, double* %31
%33 = fsub double %29, %32
store double %33, double* %9
%34 = load double*, double** %4
%35 = getelementptr inbounds double, double* %34, i64 0
%36 = load double, double* %35
%37 = load double, double* %7
%38 = load double*, double** %4
%39 = getelementptr inbounds double, double* %38, i64 4
%40 = load double, double* %39
%41 = load double, double* %8
%42 = fmul double %40, %41
%43 = call double @llvm.fmuladd.f64(double %36, double %37, double %42)
%44 = load double*, double** %4
%45 = getelementptr inbounds double, double* %44, i64 8
%46 = load double, double* %45
%47 = load double, double* %9
%48 = call double @llvm.fmuladd.f64(double %46, double %47, double %43)
%49 = fptrunc double %48 to float
%50 = load float*, float** %6
%51 = getelementptr inbounds float, float* %50, i64 0
store float %49, float* %51
%52 = load double*, double** %4
%53 = getelementptr inbounds double, double* %52, i64 1
%54 = load double, double* %53
%55 = load double, double* %7
%56 = load double*, double** %4
%57 = getelementptr inbounds double, double* %56, i64 5
%58 = load double, double* %57
%59 = load double, double* %8
%60 = fmul double %58, %59
%61 = call double @llvm.fmuladd.f64(double %54, double %55, double %60)
%62 = load double*, double** %4
%63 = getelementptr inbounds double, double* %62, i64 9
%64 = load double, double* %63
%65 = load double, double* %9
%66 = call double @llvm.fmuladd.f64(double %64, double %65, double %61)
%67 = fptrunc double %66 to float
%68 = load float*, float** %6
%69 = getelementptr inbounds float, float* %68, i64 1
store float %67, float* %69
%70 = load double*, double** %4
%71 = getelementptr inbounds double, double* %70, i64 2
%72 = load double, double* %71
%73 = load double, double* %7
%74 = load double*, double** %4
%75 = getelementptr inbounds double, double* %74, i64 6
%76 = load double, double* %75
%77 = load double, double* %8
%78 = fmul double %76, %77
%79 = call double @llvm.fmuladd.f64(double %72, double %73, double %78)
%80 = load double*, double** %4
%81 = getelementptr inbounds double, double* %80, i64 10
%82 = load double, double* %81
%83 = load double, double* %9
%84 = call double @llvm.fmuladd.f64(double %82, double %83, double %79)
%85 = fptrunc double %84 to float
%86 = load float*, float** %6
%87 = getelementptr inbounds float, float* %86, i64 2
store float %85, float* %87
ret void
}

LLVM IR (-O2):
define void @inverse_transform44d3f(double* nocapture %0, float* nocapture %1, float* nocapture writeonly %2) {
%4 = load float, float* %1
%5 = fpext float %4 to double
%6 = getelementptr inbounds double, double* %0, i64 3
%7 = load double, double* %6
%8 = fsub double %5, %7
%9 = getelementptr inbounds float, float* %1, i64 1
%10 = load float, float* %9
%11 = fpext float %10 to double
%12 = getelementptr inbounds double, double* %0, i64 7
%13 = load double, double* %12
%14 = fsub double %11, %13
%15 = getelementptr inbounds float, float* %1, i64 2
%16 = load float, float* %15
%17 = fpext float %16 to double
%18 = getelementptr inbounds double, double* %0, i64 11
%19 = load double, double* %18
%20 = fsub double %17, %19
%21 = load double, double* %0
%22 = getelementptr inbounds double, double* %0, i64 4
%23 = load double, double* %22
%24 = fmul double %14, %23
%25 = tail call double @llvm.fmuladd.f64(double %21, double %8, double %24)
%26 = getelementptr inbounds double, double* %0, i64 8
%27 = load double, double* %26
%28 = tail call double @llvm.fmuladd.f64(double %27, double %20, double %25)
%29 = fptrunc double %28 to float
store float %29, float* %2
%30 = getelementptr inbounds double, double* %0, i64 1
%31 = load double, double* %30
%32 = getelementptr inbounds double, double* %0, i64 5
%33 = load double, double* %32
%34 = fmul double %14, %33
%35 = tail call double @llvm.fmuladd.f64(double %31, double %8, double %34)
%36 = getelementptr inbounds double, double* %0, i64 9
%37 = load double, double* %36
%38 = tail call double @llvm.fmuladd.f64(double %37, double %20, double %35)
%39 = fptrunc double %38 to float
%40 = getelementptr inbounds float, float* %2, i64 1
store float %39, float* %40
%41 = getelementptr inbounds double, double* %0, i64 2
%42 = load double, double* %41
%43 = getelementptr inbounds double, double* %0, i64 6
%44 = load double, double* %43
%45 = fmul double %14, %44
%46 = tail call double @llvm.fmuladd.f64(double %42, double %8, double %45)
%47 = getelementptr inbounds double, double* %0, i64 10
%48 = load double, double* %47
%49 = tail call double @llvm.fmuladd.f64(double %48, double %20, double %46)
%50 = fptrunc double %49 to float
%51 = getelementptr inbounds float, float* %2, i64 2
store float %50, float* %51
ret void
}