gh-148285: Allow recording uops after specializing uops

[adityakrmishra]

• Fixes Allow recording uops after specializing uops #148285

The Issue:
Currently, analyzer.py uses a strict positional first = True check when validating macro structures. This strictly forces any uop with records_value == True to be at index 0, which prevents Tier 2 recording uops from safely trailing Tier 1 specializing uops.

The Fix:
Replaced the boolean first check with a state tracker (valid_recording_pos) in add_macro().

• valid_recording_pos starts as True.
• It remains True if the parsed part is a specializing uop (uop.properties.tier == 1).
• It ignores CacheEffect and flush parts.
• It flips to False for any other instruction, properly closing the gate.

This safely allows structures like:
macro(X) = _SPECIALIZE_X + _RECORD_TOS_TYPE + unused/1 + _X;

• Issue: Allow recording uops after specializing uops #148285

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[Sacul0457]

Hmm, while this does allow _RECORD uops to come after _SPECIALIZE uops, it also:

• Allows _RECORD uops to come after non _SPECIALIZE uops since not all tier-1 uops are specializing.
• No longer ensures both recording and specializing uops comes first

Example that violates both:

macro(LOAD_SUPER_ATTR) =
    _LOAD_SUPER_ATTR + // tier1 uop
    _RECORD_TOS_TYPE + 
    _SPECIALIZE_LOAD_SUPER_ATTR +
    _PUSH_NULL_CONDITIONAL;

BUT, you should wait for a core dev to review this as I may have misunderstood something.

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[adityakrmishra]

@Sacul0457 Good catch! You are entirely correct—my previous logic conflated all tier1 uops with specializing uops, which was too permissive. I also tangled up the Git history on this branch, so I have closed this PR and opened a clean one with a much stricter positional index check that specifically guards for SPECIALIZE prefixes.

The new PR is here: #148373
Thanks for the review