Matrix exponential compiles slowly on Julia 1.0

Here's a simple example:

julia> using Pkg, LinearAlgebra, StaticArrays;

julia> v = @MMatrix zeros(Float64, 5, 5);

julia> v[2, 3] = -π;

julia> v[3, 2] = π;

julia> v
5×5 MArray{Tuple{5,5},Float64,2,25}:
0.0  0.0       0.0      0.0  0.0
0.0  0.0      -3.14159  0.0  0.0
0.0  3.14159   0.0      0.0  0.0
0.0  0.0       0.0      0.0  0.0
0.0  0.0       0.0      0.0  0.0

On Julia 1.1, this compiles and runs quickly

julia> @time exp(v)
8.741098 seconds (23.58 M allocations: 983.001 MiB, 8.48% gc time)
5×5 MArray{Tuple{5,5},Float64,2,25}:
1.0   0.0           0.0           0.0   0.0
-0.0  -1.0          -2.35127e-16  -0.0  -0.0
0.0   2.35127e-16  -1.0           0.0   0.0
0.0   0.0           0.0           1.0   0.0
0.0   0.0           0.0           0.0   1.0

julia> versioninfo()
Julia Version 1.1.0
Commit 80516ca202 (2019-01-21 21:24 UTC)
Platform Info:
OS: macOS (x86_64-apple-darwin14.5.0)
CPU: Intel(R) Core(TM) i7-4870HQ CPU @ 2.50GHz
WORD_SIZE: 64
LIBM: libopenlibm
LLVM: libLLVM-6.0.1 (ORCJIT, haswell)

julia> Pkg.status("StaticArrays")
    Status `~/.julia/environments/v1.1/Project.toml`
  [90137ffa] StaticArrays v0.11.0 #master (https://github.com/JuliaArrays/StaticArrays.jl)

On Julia 1.0, it takes nearly 50x longer:

julia> @time exp(v)
406.894653 seconds (24.31 M allocations: 1.512 GiB, 0.31% gc time)
5×5 MArray{Tuple{5,5},Float64,2,25}:
1.0   0.0           0.0           0.0   0.0
-0.0  -1.0          -2.35127e-16  -0.0  -0.0
0.0   2.35127e-16  -1.0           0.0   0.0
0.0   0.0           0.0           1.0   0.0
0.0   0.0           0.0           0.0   1.0

julia> versioninfo()
Julia Version 1.0.4
Commit 38e9fb7f80 (2019-05-16 03:38 UTC)
Platform Info:
  OS: macOS (x86_64-apple-darwin15.6.0)
  CPU: Intel(R) Core(TM) i7-4870HQ CPU @ 2.50GHz
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-6.0.0 (ORCJIT, haswell)

julia> Pkg.installed()["StaticArrays"]
v"0.11.0"

The culprit appears to be these lines

https://github.com/JuliaArrays/StaticArrays.jl/blob/e77e3ef0bdb12f5dbda0bcfeba21d758616bd2cb/src/expm.jl#L105-L112

If I remove them and everything afterward, the function compiles and returns quickly. Also, if I interrupt the stalled command (exp(v)) with Ctrl+C, and then re-run the command, it runs instantly.

Start with the reproducible StaticArrays example and inspect src/expm.jl at lines 105-112, comparing Julia 1.0.4 with 1.1.0. Measure compilation and execution for exp(v), then identify whether the reported slowdown remains and document or test the resulting behavior.