Before this commit the DLA frontend was not ready to handle all the
possible combinations of integer- and pointer-typed arithmetic that was
used to compute SCEVs.
This could cause crashes when dealing with pointer-typed SCEVs.
This commit fixes the issues by converting all pointer-typed expressions
to integers, and resizing integers to the same size before adding them.
Now extractvalue instruction are replaced by dedicated
OpaqueExtractValue custom opcode, that prevents LLVM from doing strange
things with extractvalues during optimizations (such as e.g. sinking).
This is important since extractvalue instructions and struct-typed
values in general in our LLVM IR are not real first-class citizens, but
only a byproduct of the binary lifting process, and they actually
represent bundles of registers that are returned from isolated
functions.
For segmentRef type of the segment and type returned by segmentRef
function are the same.
For cstringLiteral every call returns pointer to 1-byte type. Pointer is
offsetted by value of strlen+1. strlen is fetched from metadata.
Additionally, all uses of cstringLiteral function has same type as the
type of cstringLiteral (pointer to 1-byte).
Before this commit we were not adding nodes to DLATypeSystem for calls
with 0 uses.
This commit fixes the problem, and only avoids adding nodes for calls
that return void.
Before this commit, the creation of intra-procedural types and edges
was too liberal, possibly leading to creation of pointer edges starting
from nodes that were not pointer-sized.
This commit fixes the issue, never creating outgoing pointer edges from
non-pointer-sized nodes.
This commit adds placeholder pointer nodes to the DLA graph during
initialization, to point to nodes that represent model types whose size
should not altered during the Middleend.
These two parts of the code needed to be separated into libraries
because they were used both by the old C backend and by
IRCanonicalization.
Now that the old C backend is dead, they have been incorporated into
IRCanonicalization.
Further changes are necessary to strip away the last leftovers of the
old C backend from MarkAnalysis.
Change company name to "rev.ng Labs Srl" in all license headers
to reflect changed company name and legal status
Add missing license headers to files that didn't have one
Nested SCEVAddRecs are not guaranteed to have strides that go from
larger to smaller. Both cases are valid and can convey interesting
information to DLA. But DLA assumes that the outermost strides are
always larger than the innermost, because this is the only scenario
allowed by well-nested types.
This commit re-orders the strides (and the associated trip counts) so
that they always go from larger to smaller sizes.
The assertGetLayoutTypePreConditions methods didn't really need to be
exposed as methods in a header. This commit moves them to static
standalone functions in the only place they're used.
Alessandro Di Federico