Fold more branches via O1K_VN <relop> O2K_VN comparisons

[EgorBo]

Minimal example:

if (x > 10 && x < 100)
{
    if (y > x) // means y > 11
    {
        return y > 0; // always true 

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[Copilot]

Pull request overview

This PR extends CoreCLR JIT global assertion propagation and range analysis to reason about signed comparisons where both operands are arbitrary value numbers (VN VN). The goal is to enable additional branch folding by chaining relational facts (e.g., deriving bounds for y from y > x plus existing bounds for x).

Changes:

• Add a new global-AP assertion operand kind (O2K_VN) to represent “op2 is an arbitrary VN” for relop assertions.
• Teach global assertion generation to create VN-to-VN relop assertions (with complementary assertions) in selected signed int32 cases.
• Enhance RangeCheck::MergeEdgeAssertions / GetRangeFromAssertionsWorker to tighten ranges using VN-to-VN assertions via bounded recursion.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
src/coreclr/jit/rangecheck.h	Declares MergeEdgeAssertionsWorker to support bounded recursive VN-to-VN assertion resolution.
src/coreclr/jit/rangecheck.cpp	Implements worker/wrapper split for edge-assertion merging and adds VN-to-VN relop-driven range tightening.
src/coreclr/jit/compiler.h	Adds O2K_VN, updates assertion comparisons, and adds a factory for VN-to-VN relop assertions.
src/coreclr/jit/assertionprop.cpp	Prints/debug-checks O2K_VN, registers op2 VN for lookup, and creates VN-to-VN relop assertions on JTRUE when profitable.

[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.