[refactor] Move c_quoted into taichi/utils/

[k-ye]

Moving this to a common utils so that IR printer can also use it.

@archibate I don't have a way to test the C backend on Mac. Could you confirm this doesn't break?

Related issue = #1350 (comment)

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Codecov Report

Merging #1376 into master will decrease coverage by 0.05%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #1376      +/-   ##
==========================================
- Coverage   85.65%   85.60%   -0.06%     
==========================================
  Files          19       19              
  Lines        3373     3375       +2     
  Branches      624      625       +1     
==========================================
  Hits         2889     2889              
- Misses        354      356       +2     
  Partials      130      130              

Impacted Files	Coverage Δ
python/taichi/lang/ast_checker.py	72.22% <0.00%> (-2.07%)	⬇️

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[archibate]

Compiling & running happily on my end! Thanks!
Btw, would you help me set up C backend on OS X after #1354 gets merged?

[archibate]

But, how about to move this to lang_util.h and lang_util.cpp? I'm afraid adding a new C++ file just for this may increase compile time.. Or we do lang_util.cpp refactor IAPR?

[k-ye]

But, how about to move this to lang_util.h and lang_util.cpp? I'm afraid adding a new C++ file just for this may increase compile time..

Is there any evidence this might hurt compilation time? I'd suggest to keep lang_util as simple as possible, because it has been included by almost all the files, in order to have this TLANG_NAMESPACE_BEGIN|END macros?

[k-ye]

Btw, would you help me set up C backend on OS X after #1354 gets merged?

Sure. I just did a local test with C backend enabled. Didn't encounter compilation error at least...

[archibate]

lang_util

Sounds reasonable, thank for the hard work!

Didn't encounter compilation error

Would you run

ti.init(ti.cc)

@ti.kernel
def hello():
  print('Hello, world!')

hello()

to confirm? TTYM in the C backend issue. Let's merge this for now.