JIT: fold trivial redundant comparisons on loop induction variables

[EgorBo]

Closes #130206

static void Test()
{
    for (int i = 0; i < 100; i++)
    {
        if (i >= 0) // never false
        {
            Console.WriteLine("Hi");
        }
    }
}

 G_M24707_IG02:
        xor      ebx, ebx
        mov      rsi, 0x...      ; 'Hi'
-       jmp      SHORT G_M24707_IG05
-G_M24707_IG03:
-       inc      ebx
-G_M24707_IG04:
-       test     ebx, ebx
-       jl       SHORT G_M24707_IG03
-G_M24707_IG05:
+G_M24707_IG03:
        mov      rcx, rsi
        call     [System.Console:WriteLine(System.String)]
        inc      ebx
        cmp      ebx, 100
-       jl       SHORT G_M24707_IG04
+       jl       SHORT G_M24707_IG03

Some nice diffs, mostly in tests, though.

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[Copilot]

Pull request overview

This PR adjusts assertion propagation’s SSA-based range query budget so that RangeCheck::TryGetRange can successfully compute ranges for common loop induction-variable patterns, enabling folding of trivially redundant comparisons.

Changes:

• Increase the default SSA walk budget used by assertionprop’s slow GetRange path from 64 to 256.
• Add an explanatory comment describing why TryGetRange needs a larger shared budget due to multiple internal SSA walks.

[EgorBo]

@MihuBot -nuget

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Pull request overview

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