[ir] Add RAII guards to IR Builder #2242
Conversation
taichi/ir/ir_builder.cpp
Outdated
| if (location_ >= 0 && location_ < loop_->parent->size() && | ||
| loop_->parent->statements[location_].get() == loop_) { | ||
| // faster than set_insertion_point_to_after() | ||
| builder_.set_insertion_point({loop_->parent, location_ + 1}); |
There was a problem hiding this comment.
At a high level, what does this condition mean? Something like "the number of statements before the loop statements stays the same"? I'm wondering in what scenario the number of statements changes - it sounds to me that when using the guard the users are only supposed to modify the statements within the guarded scope.
There was a problem hiding this comment.
Something like "the number of statements before the loop statements stays the same"?
Yes, exactly. This condition is to prevent some random things like
auto *loop = builder.create_range_for(zero, ten);
{
IRBuilder::LoopGuard _(builder, loop);
builder.create_add(...);
builder.set_insertion_point_to(some_random_insertion_point);
builder.create_add(...); // if some_random_insertion_point is in the same block but before the loop, it may cause trouble...
} // here I set the insertion point to a *defined* place -- the point after the loop.or
auto *loop = builder.create_range_for(zero, ten);
builder.create_add(...); // this is inserted to the place after the loop so we can't locate the loop in O(1) then
{
IRBuilder::LoopGuard _(builder, loop);
builder.create_add(...);
}There was a problem hiding this comment.
OK sounds good! Let's add these comments to the code and this PR is ready to merge!
There was a problem hiding this comment.
I set the insertion point to a defined place -- the point after the loop.
Could you add this comment to the header ? It describes the API's behavior.
Co-authored-by: Yuanming Hu <yuanming-hu@users.noreply.github.com>
taichi/ir/ir_builder.cpp
Outdated
| if (location_ >= 0 && location_ < loop_->parent->size() && | ||
| loop_->parent->statements[location_].get() == loop_) { | ||
| // faster than set_insertion_point_to_after() | ||
| builder_.set_insertion_point({loop_->parent, location_ + 1}); |
There was a problem hiding this comment.
OK sounds good! Let's add these comments to the code and this PR is ready to merge!
taichi/ir/ir_builder.cpp
Outdated
| if (location_ >= 0 && location_ < loop_->parent->size() && | ||
| loop_->parent->statements[location_].get() == loop_) { | ||
| // faster than set_insertion_point_to_after() | ||
| builder_.set_insertion_point({loop_->parent, location_ + 1}); |
There was a problem hiding this comment.
I set the insertion point to a defined place -- the point after the loop.
Could you add this comment to the header ? It describes the API's behavior.
Related issue = #2193
This PR adds
IRBuilder::LoopGuardandIRBuilder::IfGuardto make writing control flows with IR Builder easier.These classes' objects automatically set the insertion point in O(1) time if the insertion point is never manually set in their lifetime by other functions.
[Click here for the format server]