When mangling names of function local variables, use a map from variable names to integer counts.  This way, each name can still start at 1, but the O(N^2) lookup algorithm is avoided.
When mangling names of function local variables, use a map from variable
names to integer counts.  This way, each name can still start at 1, but the
O(N^2) lookup algorithm is avoided.

Previously, for each variable, we checked if the name was already taken, then
checked name1, name2, ...

This makes a huge difference in codegen time for the Spiral FFT tests.


git-svn-id: 88467cb1fb04b8a755be7e1ee1026be4190196ef@14916 3a8e244f-b0f2-452b-bcba-4c88e055c3ca

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