refactor binopoffset with symbolic pointer offset tracking #784
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overview
refactors the binopoffset implementation to use symbolic offset tracking instead of eagerly updating pointer metadata. follows the approach outlined in branch 709-binopoffset-again.
changes
data structures
PtrEmulationsort to track pointer offsets symbolicallyptrEmulation(wraps metadata),ptrOffset(valid offset),ptrOrigSize(original allocation size),InvalidOffset(out-of-bounds)PtrLocalValuein python to usePtrEmulationinstead of rawMetadatapointer operations
binOpOffsetto create offset nodes instead of immediately checking boundstype conversions
#convertPtrEmulto handle array ↔ element pointer conversionsptrOrigSizeto remember allocation sizeInvalidOffsetif out of boundsintrinsics
std::intrinsics::offset(signed offset)ptr::add(unsigned, forward offset)ptr::sub(unsigned, backward offset)tests
current status
dereferencing logic needs refinement - the tests are failing because
#applyPtrOffsetcurrently usesPointerOffsetprojection for all cases. according to the notes in 709-binopoffset-again, when dereferencingptrOffset(N, ptrOrigSize(_))(pointer to single element), it should useConstantIndexprojection instead ofPointerOffsetwhich expects aRangevalue.the current implementation works for array/slice pointers but gets stuck when dereferencing offset pointers to single elements.
related
binOpOffset#709 (if i fix the dereference logic)binOpOffset#746 (original binopoffset implementation)