[pdb] Add -type-stats and sort stats by descending size
Summary:
It prints this on chromium browser_tests.exe.pdb:
Types
Total: 5647475 entries ( 371,897,512 bytes, 65.85 avg)
--------------------------------------------------------------------------
LF_CLASS: 397894 entries ( 119,537,780 bytes, 300.43 avg)
LF_STRUCTURE: 236351 entries ( 83,208,084 bytes, 352.05 avg)
LF_FIELDLIST: 291003 entries ( 66,087,920 bytes, 227.10 avg)
LF_MFUNCTION: 1884176 entries ( 52,756,928 bytes, 28.00 avg)
LF_POINTER: 1149030 entries ( 13,877,344 bytes, 12.08 avg)
LF_ARGLIST: 789980 entries ( 12,436,752 bytes, 15.74 avg)
LF_METHODLIST: 361498 entries ( 8,351,008 bytes, 23.10 avg)
LF_ENUM: 16069 entries ( 6,108,340 bytes, 380.13 avg)
LF_PROCEDURE: 269374 entries ( 4,309,984 bytes, 16.00 avg)
LF_MODIFIER: 235602 entries ( 2,827,224 bytes, 12.00 avg)
LF_UNION: 9131 entries ( 2,072,168 bytes, 226.94 avg)
LF_VFTABLE: 323 entries ( 207,784 bytes, 643.29 avg)
LF_ARRAY: 6639 entries ( 106,380 bytes, 16.02 avg)
LF_VTSHAPE: 126 entries ( 6,472 bytes, 51.37 avg)
LF_BITFIELD: 278 entries ( 3,336 bytes, 12.00 avg)
LF_LABEL: 1 entries ( 8 bytes, 8.00 avg)
The PDB is overall 1.9GB, so the LF_CLASS and LF_STRUCTURE declarations
account for about 10% of the overall file size. I was surprised to find
that on average LF_FIELDLIST records are short. Maybe this is because
there are many more types with short member lists than there are
instantiations with lots of members, like std::vector.
Reviewers: aganea, zturner
Subscribers: llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59672
llvm-svn: 356813
e6a81b9bec