Changes

[mlir][Shape] Make sure tensor_cast(constant_shape) folding uses the correct type

This is still subtle, but I think the test cases are sufficient to show
that it works.

Differential Revision: https://reviews.llvm.org/D92927

[Hexagon] Fold single-use variables into assert. NFCI.

Silences unused variable warnings in Release builds.

[lldb][NFC] Fix a typo in TestCppMultipleInheritance

Remove Shapet assignment operator that's identical to the default. NFC.

[TruncInstCombine] Remove scalable vector restriction

Differential Revision: https://reviews.llvm.org/D92819

[mlir] Explicitly track branch instructions in translation to LLVM IR

The current implementation of the translation to LLVM IR relies on the
existence of a one-to-one mapping between MLIR blocks and LLVM IR basic blocks
in order to configure PHI nodes with appropriate source blocks. The one-to-one
mapping model is broken in presence of OpenMP operations that use LLVM's
OpenMPIRBuilder, which produces multiple blocks under the hood. This can lead
to invalid LLVM IR being emitted if OpenMPIRBuilder moved the branch operation
into a basic block different from the one it was originally created in;
specifically, a block that is not a direct predecessor could be used in the PHI
node. Instead, keep track of the mapping between MLIR LLVM dialect branch
operations and their LLVM IR counterparts and take the parent basic block of
the LLVM IR instruction at the moment of connecting the PHI nodes to
predecessors.

This behavior cannot be triggered as of now, but will be once we introduce the
conversion of OpenMP workshare loops.

Reviewed By: kiranchandramohan

Differential Revision: https://reviews.llvm.org/D92845

[ARM] Remove copies from low overhead phi inductions.

The phi created in a low overhead loop gets created with a default
register class it seems. There are then copied inserted between the low
overhead loop pseudo instructions (which produce/consume GPRlr
instructions) and the phi holding the induction. This patch removes
those as a step towards attempting to make t2LoopDec and t2LoopEnd a
single instruction, and appears useful in it's own right as shown in the
tests.

Differential Revision: https://reviews.llvm.org/D91267