MagnitudeOS/littlefs
1
0
Fork 0
forked from Imagelibrary/littlefs
Code Pull Requests Activity

Tweaked struct tag encoding so b*/m* tags are earlier

Browse Source 
These b*/m* struct tags have a common pattern that would be good to
emphasize in the encoding. The later struct tags get a bit more messy as
they leave space for future possible extensions.

New encoding:

  LFSR_TAG_STRUCT         0x03tt  v--- --11 -ttt ttrr

  LFSR_TAG_DATA           0x0300  v--- --11 ---- ----
  LFSR_TAG_BLOCK          0x0304  v--- --11 ---- -1rr
  LFSR_TAG_BSHRUB         0x0308  v--- --11 ---- 1---
  LFSR_TAG_BTREE          0x030c  v--- --11 ---- 11rr
  LFSR_TAG_MROOT          0x0310  v--- --11 ---1 --rr
  LFSR_TAG_MDIR           0x0314  v--- --11 ---1 -1rr
  LFSR_TAG_MSHRUB*        0x0318  v--- --11 ---1 1---
  LFSR_TAG_MTREE          0x031c  v--- --11 ---1 11rr
  LFSR_TAG_DID            0x0320  v--- --11 --1- ----
  LFSR_TAG_BRANCH         0x032c  v--- --11 --1- 11rr

  * Hypothetical

Note that all shrubs currently end with 1---, and all btrees, including
the awkward branch tag, end with 11rr.

This had no impact on code size:

           code          stack
  before: 33564           2816
  after:  33564 (+0.0%)   2816 (+0.0%)
This commit is contained in:
Christopher Haster
2024-04-24 02:14:20 -05:00
parent 5fa85583cd
commit 6e5d314c20
7 changed files with 45 additions and 45 deletions
Download Patch File Download Diff File Expand all files Collapse all files

14
scripts/dbgtag.py
View File

@@ -28,11 +28,11 @@ TAG_DATA = 0x0300
TAG_BLOCK = 0x0304
TAG_BSHRUB = 0x0308
TAG_BTREE = 0x030c
TAG_DID = 0x0310
TAG_BRANCH = 0x031c
TAG_MROOT = 0x0321
TAG_MDIR = 0x0325
TAG_MTREE = 0x032c
TAG_MROOT = 0x0311
TAG_MDIR = 0x0315
TAG_MTREE = 0x031c
TAG_DID = 0x0320
TAG_BRANCH = 0x032c
TAG_UATTR = 0x0400
TAG_SATTR = 0x0600
TAG_SHRUB = 0x1000
@@ -157,11 +157,11 @@ def tagrepr(tag, w=None, size=None, off=None):
else 'block' if (tag & 0xfff) == TAG_BLOCK
else 'bshrub' if (tag & 0xfff) == TAG_BSHRUB
else 'btree' if (tag & 0xfff) == TAG_BTREE
else 'did' if (tag & 0xfff) == TAG_DID
else 'branch' if (tag & 0xfff) == TAG_BRANCH
else 'mroot' if (tag & 0xfff) == TAG_MROOT
else 'mdir' if (tag & 0xfff) == TAG_MDIR
else 'mtree' if (tag & 0xfff) == TAG_MTREE
else 'did' if (tag & 0xfff) == TAG_DID
else 'branch' if (tag & 0xfff) == TAG_BRANCH
else 'struct 0x%02x' % (tag & 0xff),
' w%d' % w if w else '',
' %s' % size if size is not None else '')