SLP vectorizer on simple function not working

The attached function should be vectorizable with a SIMD width of 4. However, the SLP vectorizer tells me it cannot schedule the bundle.

llvm-3.6/bin/opt -datalayout -basicaa -slp-vectorizer -debug-only SLP -S < func_simple_scalar.ll -o tmp.ll &> out

SLP: Analyzing blocks in main.
SLP: Found 4 stores to vectorize.
SLP: Analyzing a store chain of length 4.
SLP: Analyzing a store chain of length 4
SLP: Analyzing 4 stores at offset 0
SLP: bundle: store float %4, float* %5
SLP: initialize schedule region to store float %4, float* %5
SLP: extend schedule region end to store float %10, float* %11
SLP: extend schedule region end to store float %16, float* %17
SLP: extend schedule region end to store float %22, float* %23
SLP: try schedule bundle [ store float %4, float* %5; store float %10, float* %11; store float %16, float* %17; store float %22, float* %23] in block entrypoint
SLP: update deps of [ store float %4, float* %5; store float %10, float* %11; store float %16, float* %17; store float %22, float* %23]
SLP: update deps of / store float %10, float* %11
SLP: update deps of / store float %16, float* %17
SLP: update deps of / store float %22, float* %23
SLP: update deps of %21 = load float* %20
SLP: update deps of %22 = fmul float %21, %19
SLP: update deps of %19 = load float* %18
SLP: update deps of %15 = load float* %14
SLP: update deps of %16 = fmul float %15, %13
SLP: update deps of %13 = load float* %12
SLP: update deps of %9 = load float* %8
SLP: update deps of %10 = fmul float %9, %7
SLP: update deps of %7 = load float* %6
SLP: We are not able to schedule this bundle!
SLP: cancel scheduling of [ store float %4, float* %5; store float %10, float* %11; store float %16, float* %17; store float %22, float* %23]
SLP: Calculating cost for tree of size 1.
SLP: Check whether the tree with height 1 is fully vectorizable .
SLP: Found cost=2147483647 for VF=4

What am I missing?

Thanks,
Frank

func_simple_scalar.ll (1.05 KB)

Okay, it was the missing 'noalias' attribute on the arguments. Damn, I thought I had that down.

Sorry for the noise.

Thanks,
Frank