[WIP][rocprofiler-sdk] Counters implement variable bit allocation for dimension encoding

[venkat1361]

Motivation

Some counters have DIMENSION_INSTANCES greater than 64 range, which doesn't fit in current implementation of using 6bits for representing dimension index.

Technical Details

• id_decode.hpp: Added DIM_BIT_LENGTHS[] and DIM_BIT_OFFSETS[] arrays with get_dim_bit_length() and get_dim_bit_offset() helpers. Added static_assert to validate bit allocation. DIMENSION_INSTANCE increased from 6 to 10 bits (1023 max value).
• evaluate_ast.cpp: Updated perform_reduction(), get_int_encoded_dimensions_from_string(), and perform_selection() to use variable bit allocation.

JIRA ID

Test Plan

• Test files: Updated to compute per-dimension max values dynamically.

Test Result

• rocprofiler-sdk unit tests should pass

Submission Checklist

• Look over the contributing guidelines at https://github.com/ROCm/ROCm/blob/develop/CONTRIBUTING.md#pull-requests.

[Copilot]

Pull request overview

This PR updates rocprofiler-sdk’s counter instance ID dimension encoding from a fixed, evenly-split bit layout to a variable per-dimension bit allocation (notably expanding INSTANCE to 10 bits), and adjusts evaluation/tests to match the new layout.

Changes:

• Introduces per-dimension bit length/offset helpers and updates ID set/get logic to use them.
• Updates AST evaluation logic (reduction/selection) and unit tests to use the new per-dimension masks.
• Expands dimension test coverage to iterate up to each dimension’s max representable value.

Reviewed changes

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

File	Description
projects/rocprofiler-sdk/source/lib/rocprofiler-sdk/counters/id_decode.hpp	Adds variable bit-length/offset tables + helpers; updates dimension encode/decode to use them.
projects/rocprofiler-sdk/source/lib/rocprofiler-sdk/counters/evaluate_ast.cpp	Updates reduction/selection masking and parsing to use variable bit allocation.
projects/rocprofiler-sdk/source/lib/rocprofiler-sdk/counters/tests/dimension.cpp	Updates tests to compute max values per-dimension and iterate accordingly.
projects/rocprofiler-sdk/source/lib/rocprofiler-sdk/counters/tests/evaluate_ast_test.cpp	Updates test-side masking logic to match the new variable bit allocation.

Comments suppressed due to low confidence (1)

projects/rocprofiler-sdk/source/lib/rocprofiler-sdk/counters/evaluate_ast.cpp:155

• perform_reduction() builds mask_dim from get_dim_bit_length()/offset without handling ROCPROFILER_DIMENSION_NONE. If the AST specifies DIMENSION_NONE in the reduction list, get_dim_bit_length() returns 0, producing mask_dim == 0 and leaving the record id unchanged (i.e., no reduction happens). Either reject DIMENSION_NONE for reduction/select operations or treat it as a special case that clears the full 48-bit dimension field.

            // Use variable bit allocation for each dimension
            uint64_t dim_bit_length = get_dim_bit_length(dim);
            uint64_t dim_bit_offset = get_dim_bit_offset(dim);
            int64_t  mask_dim       = ((1ULL << dim_bit_length) - 1) << dim_bit_offset;

            rec.id = rec.id | mask_dim;
            rec.id = rec.id ^ mask_dim;
        }

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