Fix VS 2012 build (unsupported nearbyinf, truncf)
Remove compiler specific preprocessor directives
Vectorize game_of_life with pnacl

Required converting an int8 -> int32 cast to scalar code
Merge pull request #540 from halide/linear_solver

Added a linear solver mutator.
Added LinearSolve.h/cpp to CMake build.
Add EXPORT qualifiers
Added comments to the new versions of expr_uses_var(s). Added EXPORT macros to expr_uses_var for Windows support.
Merge pull request #545 from halide/scoped_expr_uses_vars

Added an optional scope argument to expr_uses_var(s).
Fix store collector for upsample pattern

The store collector was bailing out when it found too many stores,
rather than only considering the first few. e.g:

f[ramp(a, 2, 4)] = ...
f[ramp(a+1, 2, 4)] = ...
f[ramp(b, 2, 4)] = ...
f[ramp(b+1, 2, 4)] = ...

can be rewritten into two interleaving stores, but the store collector
was finding four stores and bailing entirely.
Merge pull request #534 from pgec/VS2012_build_fix

Fix VS 2012 build
Add some braces.
Merge branch 'master' of github.com:halide/Halide
Changed the names of the BranchUtils files to BranchVisitors. Added some more comments to BranchVisitors.cpp file at the top of each class to indicate what it does. Rearrange the order of the functions and visitors in the file to match the order in which they are intended to be used. Also, fixed a minor but important bug that could potentially lead to infinite loops when a select expr was found in the condition of an if stmt.
Merge master