Add realloc and remove redundancies

[pavel-kirienko]

Closes #21

[Copilot]

Pull request overview

This PR adds o1heapReallocate functionality to enable efficient memory reallocation with constant-time complexity in most cases, addressing issue #21. The implementation includes comprehensive optimization of internal functions and removal of the trace functionality that was added in v2.2.

Changes:

• Adds o1heapReallocate() API with multiple strategies: shrink-in-place, expand-forward, expand-backward, and alloc-copy-free fallback
• Removes log2Ceil function (optimization: reuses log2Floor where quotients are powers of 2)
• Optimizes rebin/unbin by passing fragment sizes as parameters to avoid redundant fragGetSize calls
• Removes trace functionality (O1HEAP_TRACE, o1heapTraceAllocate, o1heapTraceFree)
• Adds comprehensive test coverage for all realloc scenarios including edge cases

Reviewed changes

Copilot reviewed 16 out of 17 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
o1heap/o1heap.c	Implements o1heapReallocate with 4 strategies; optimizes rebin/unbin; removes log2Ceil and trace; adds larger() helper
o1heap/o1heap.h	Documents new o1heapReallocate API; removes trace function declarations
tests/test_general.cpp	Adds 956 lines of comprehensive realloc tests; removes trace tests; reduces test memory/iterations
tests/test_api_exhaustive.cpp	Adds realloc edge case tests with realloc operations in random walk tests
tests/internal.hpp	Adds reallocate() wrapper method
tests/CMakeLists.txt	Fixes paths from CMAKE_SOURCE_DIR to CMAKE_CURRENT_SOURCE_DIR; removes trace test
tests/.clang-tidy	Disables -use-ranges and -signed-bitwise warnings
perftest/main.c	Refactors to compare o1heap vs malloc using abstraction layer
perftest/README.md	Adds benchmark results showing o1heap's performance advantages
README.md	Updates performance numbers; documents realloc addition; removes trace documentation
CMakeLists.txt	Adds top-level CMake file for project
AGENTS.md, CLAUDE.md	Adds AI agent instructions
.github/workflows/main.yml	Updates cmake to build from root directory

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