Previously, subprograms contained a metadata reference to the function they
described. Because most clients need to get or set a subprogram for a given
function rather than the other way around, this created unneeded inefficiency.
For example, many passes needed to call the function llvm::makeSubprogramMap()
to build a mapping from functions to subprograms, and the IR linker needed to
fix up function references in a way that caused quadratic complexity in the IR
linking phase of LTO.
This change reverses the direction of the edge by storing the subprogram as
function-level metadata and removing DISubprogram's function field.
Since this is an IR change, a bitcode upgrade has been provided.
Fixes PR23367. An upgrade script for textual IR for out-of-tree clients is
attached to the PR.
Differential Revision: http://reviews.llvm.org/D14265
llvm-svn: 252219
This test uses a gcov file generated in a little-endian host. The gcov
reader does not allow different endianness, so the test fails on big
endian hosts.
XFAILing for now.
llvm-svn: 247920
This adds enough machinery to support reading simple GCC AutoFDO
profiles. It now supports reading flat profiles (no function calls).
Subsequent patches will add support for:
- Inlined calls (in particular, the inline call stack is not traversed
to accumulate samples).
- Working sets and modules. These are used mostly for GCC's LIPO
optimizations, so they're not needed in LLVM atm. I'm not sure that
we will ever need them. For now, I've if0'd around the calls.
The patch also adds support in GCOV.h for gcov version V704 (generated
by GCC's profile conversion tool).
llvm-svn: 247874
