llvm/test/Transforms/Util
Adrian Prantl 4eeaa0da04 [PR27284] Reverse the ownership between DICompileUnit and DISubprogram.
Currently each Function points to a DISubprogram and DISubprogram has a
scope field. For member functions the scope is a DICompositeType. DIScopes
point to the DICompileUnit to facilitate type uniquing.

Distinct DISubprograms (with isDefinition: true) are not part of the type
hierarchy and cannot be uniqued. This change removes the subprograms
list from DICompileUnit and instead adds a pointer to the owning compile
unit to distinct DISubprograms. This would make it easy for ThinLTO to
strip unneeded DISubprograms and their transitively referenced debug info.

Motivation
----------

Materializing DISubprograms is currently the most expensive operation when
doing a ThinLTO build of clang.

We want the DISubprogram to be stored in a separate Bitcode block (or the
same block as the function body) so we can avoid having to expensively
deserialize all DISubprograms together with the global metadata. If a
function has been inlined into another subprogram we need to store a
reference the block containing the inlined subprogram.

Attached to https://llvm.org/bugs/show_bug.cgi?id=27284 is a python script
that updates LLVM IR testcases to the new format.

http://reviews.llvm.org/D19034
<rdar://problem/25256815>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@266446 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-15 15:57:41 +00:00
..
MemorySSA [MemorySSA] Make the visitor more careful with calls. 2016-03-30 03:12:08 +00:00
combine-alias-scope-metadata.ll Revert "Change memcpy/memset/memmove to have dest and source alignments." 2015-11-19 05:56:52 +00:00
flattencfg.ll
lowerswitch.ll Have a single way for creating unique value names. 2015-11-22 00:16:24 +00:00
simplify-dbg-declare-load.ll [PR27284] Reverse the ownership between DICompileUnit and DISubprogram. 2016-04-15 15:57:41 +00:00
split-bit-piece.ll [PR27284] Reverse the ownership between DICompileUnit and DISubprogram. 2016-04-15 15:57:41 +00:00
store-first-op.ll [PR27284] Reverse the ownership between DICompileUnit and DISubprogram. 2016-04-15 15:57:41 +00:00