* [ARITH] Improve detect linear equation

* fix doc

* prefetch interface added

* prefetch python comments modified. prefetch info data structure maintained.

* start injecting prefetches. first step (domain touch) implemented.

* domain touch tested.

* Prefetch ir_mutator and ir_visitor dispatch registered.

* modify domain touched from passing a func_ref to passing a tensor

* modify domain touched from passing a func_ref to passing a tensor

* modify Tensor copy to Tensor ref

* temp commit for rebase

* debug info removed, typo fixed, ready to rebase

* prefetch flatten test add!

* roll back builtin functions to side effect functions

* lint error fixed!

* add cache line size to storage flatten argument

* forgot modifications add

* change code style to dmlc-like; get rid of can_prove, use manually compute instead

* python lint error fixed

* modify instrinsic name to pass tests

* [TEST] get rid of str(), replace them by accessing attributes

* change map to list comprehension

* redundant numpy import removed

* [CODEGEN] Refactor common codegen, Verilog Codegen

* fix make

* fix mk

* update enable signal

* change function name to at neg edge

* Move test to correct place

* [IterVar/REFACTOR] Add types to IterVar

* [ARITH/REFACTOR] Move IntSet to include

* [REFACTOR/OP] Move Op detail to seperate folder.

* fix test

* loop_partition draft

* divide loop variable into constant domain and variable domain & consider multiple partitions

* process doubt interval

* fix and refactor, add relax_map arg in BoundDeduce

* fix testcase and comment

* rebase to zero, convert to SSA

* change the logic of generating loop code & fix issues

* add a testcase for relax map in deducebound && fix issues

* clean code

* const auto&

* add test_multi_if

* [ARITH/VISITOR] Modular Analysis, ExprFunctor, StmtFunctor

* retrigger

* [IRFunctor] Migrated CodegenC

* [IRFUNCTOR] Migrate CodeGenLLVM

* [IRFunctor] Migrate canonical

* [IRFunctor] Migrate vectorize

* [IRFunctor] migrate CodeGenStackVM

* [PYTHON/API] Add compare and logic build-in op for Expr

* remove 'and', 'or'

* add deducer

* [WIP] bound_deducer.cc

* move IntervalSet and StrideSet into int_set_internal.h

* add multiple failure for VariablePathFinder, add EvalSign

* consider round in deduce, add success flag

* remove Visit_(Div)

* add comment, update HalideIR

* expose intset to python

* check the sign of every expr

* set return type as ExprSignType

* fine tune

* add min & max python api for interval set

* support for conditional expr

* refactor test

* add checker for BoundDeducer

* add python check test

* fix

* fix

* change range to interval; remove converter

* remove converter declaration

* remove int_set_internal.h