[TIR] Improve Let/LetStmt support. #5949
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Let/LetStmt are useful primitives to create variable bindings. While let binding are harmful for simplification and integer analysis, they are useful for other cases: - C0: LetStmt is useful to represent a step that has side effect(e.g. call a PRNG) - C1: Let expression can be used to create deep nested expression for complicated functions. This PR improves the let support in the following ways: - Enable vectorization support for let - Change let simplification strategy to simplify the most trivial case while ignore more complicated cases(to avoid deep nest explosion) - Enhance arith module to handle const bound and modular set for let. The overall recommendation is to only use Let in the cases when necessary(C0, C1).
zhiics
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Let/LetStmt are useful primitives to create variable bindings. While let binding are harmful for simplification and integer analysis, they are useful for other cases: - C0: LetStmt is useful to represent a step that has side effect(e.g. call a PRNG) - C1: Let expression can be used to create deep nested expression for complicated functions. This PR improves the let support in the following ways: - Enable vectorization support for let - Change let simplification strategy to simplify the most trivial case while ignore more complicated cases(to avoid deep nest explosion) - Enhance arith module to handle const bound and modular set for let. The overall recommendation is to only use Let in the cases when necessary(C0, C1).
zhiics
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Let/LetStmt are useful primitives to create variable bindings. While let binding are harmful for simplification and integer analysis, they are useful for other cases: - C0: LetStmt is useful to represent a step that has side effect(e.g. call a PRNG) - C1: Let expression can be used to create deep nested expression for complicated functions. This PR improves the let support in the following ways: - Enable vectorization support for let - Change let simplification strategy to simplify the most trivial case while ignore more complicated cases(to avoid deep nest explosion) - Enhance arith module to handle const bound and modular set for let. The overall recommendation is to only use Let in the cases when necessary(C0, C1).
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Let/LetStmt are useful primitives to create variable bindings.
While let binding are harmful for simplification and integer analysis(due to the indirection), they are useful for other cases:
This PR improves the let support in the following ways:
while ignore more complicated cases(to avoid deep nest explosion)
We also relaxed the SSA checking conditions for Let expression, to allow the same var to be binded multiple times, as long as their binding value are equal to each other.
The overall recommendation is to only use Let in the cases when necessary(C0, C1).