[PATCH v7 0/3] read-cache: speed up add_index_entry

From: Jeff Hostetler <jeffhost@microsoft.com>

Version 7 addresses size_t and casting issues in strcmp_offset() and replaces shell test function with an awk expression to make the perf test run faster.

================ Teach add_index_entry_with_check() and has_dir_name() to avoid index lookups if the given path sorts after the last entry in the index.

This saves at least 2 binary searches per entry.

This improves performance during checkout and read-tree because merge_working_tree() and unpack_trees() processes a list of already sorted entries.

Jeff Hostetler (3):
  read-cache: add strcmp_offset function
  p0004-read-tree: perf test to time read-tree
  read-cache: speed up add_index_entry during checkout

 Makefile                      |   1 +
 cache.h                       |   1 +
 read-cache.c                  |  66 +++++++++++++++++++++++-
 t/helper/.gitignore           |   1 +
 t/helper/test-strcmp-offset.c |  64 +++++++++++++++++++++++
 t/perf/p0004-read-tree.sh     | 117 ++++++++++++++++++++++++++++++++++++++++++
 t/t0065-strcmp-offset.sh      |  11 ++++
 7 files changed, 259 insertions(+), 2 deletions(-)
 create mode 100644 t/helper/test-strcmp-offset.c
 create mode 100755 t/perf/p0004-read-tree.sh
 create mode 100755 t/t0065-strcmp-offset.sh