In degenerate but legal inputs, we can have functions that have no source
locations at all -- all the DebugLocs attached to instructions are empty.
LLVM didn't produce any source location for the function; with this patch
it will at least emit the function-scope source location. Demonstrated by
empty-line-info.ll
The XCOFF test modified has similar symptoms -- with this patch, the size
of the ".dwline" section grows a bit, thus shifting some of the file
internal offsets, which I've updated.
C_FILE symbols. To match the behavior of the assembler and the legacy
compiler, this includes using the generic ".file" name for the C_FILE
symbol and generating the actual file name in an auxiliary entry.
Summary: DWARF32 is not supported for XCOFF64 under non-integrated-as mode on AIX, because system assembler will fill the debug section lengths according to DWARF64 format. While in intergrated-as mode, XCOFF64 should be able to select the DWARF format.
Reviewed By: shchenz
Differential Revision: https://reviews.llvm.org/D150181
