DenseSet, SmallPtrSet, SmallSet, SetVector, and StringSet recently
gained C++23-style insert_range. This patch replaces:
Dest.insert(Src.begin(), Src.end());
with:
Dest.insert_range(Src);
This patch does not touch custom begin like succ_begin for now.
When a def in a block A reaches another block B that is in A's iterated
dominance frontier, a phi node is added to B for the def register.
A clobbering def can be created at a call instruction, for a register
clobbered by a call.
However, phi nodes are not created for a register, when one of the
reaching defs of the register is a clobbering def.
This patch adds phi nodes for registers that have a clobbering reaching
def. These additional phis help in checking reaching defs for an
instruction in RDF based copy propagation and addressing mode
optimizations.
During RDF graph construction, linkRefUp method links a register ref to
its upward reaching defs until all RegUnits of the ref have been covered
by defs.
However, when a sub-register def covers some, but not all, of the
RegUnits of a previous super-register def, a super-register ref is not
linked to the super-register def.
This can result in certain super register defs being dead code
eliminated.
This patch fixes the cover check for a register ref. A def must be
skipped only when all RegUnits of that def have already been covered by
a previously seen def.
- Add option to ignore reserved registers
- Add possibility to track selected registers or register classes only
Tracking is done based on register units, so the set of registers to track
is translated into a set of register units.
Recommit with the fix for incorrect `constexpr` with `hash` from a later
commit, and a fix for "std::swap(std::less<RegisterRef>...)" issue with
MSVC's `std::map`.
This reverts commit 859b05b02d3fd9ab6b77f2bed8df6902fe704806.
Also reverts these follow-ups:
Revert "[RDF] Remove `constexpr` from `hash"
This reverts commit 621507ce20ad8eef2986be2712631165e53b7d91.
Revert "[RDF] Do not use trailing return type after all, NFC"
This reverts commit 46e19e3a2c45e7fb5f501bdb983a7151c158304f.
Revert "[RDF] Stop looking when reached code node in getNextRef with NextOnly"
This reverts commit a049ce9d1bd5a7c1c4fcccc6a801b72b00ea8e0f.
Revert "[RDF] Use trailing return type syntax, NFC"
This reverts commit d3b34b7f3a7cbfc96aea897419f167b5ee19e61a.
Revert "[RDF] Define short type names: NodeAddr<XyzNode*> -> Xyz, NFC"
This reverts commit f8ed60b56d1948422dda924fcf450560591e8a19.
The name rdf::Use conflicts with llvm::Use when both namespaces are
used via `using namespace`. Specifically this happened in the declaration
of DataFlowGraph::newUse (in RDFGraph.cpp):
```
using namespace rdf;
Use newUse(...); <-- Lookup conflict for "Use"
```
Since the TRT lookup starts in a different namespace than that of the
leading type, this serves as a workaround. In general the rdf namespace
will not likely be introduced via `using namespace`, so this shouldn't
be a problem elsewhere.
This isn't quite using register units, but it's getting close. The phi
generation is driven by register units, but each phi still contains a
reference to a register, potentially with a mask that amounts to a unit.
In cases of explicit register aliasing this may still create phis with
references that are aliased, whereas separate phis would ideally contain
disjoint references (this is all within a single basic block).
Previously phis used maximal registers, now they use minimal. This is a
step towards both, using register units directly, and a simpler liveness
calculation algorithm. The idea is that a phi cannot reach a reference
to anything smaller than the phi itself represents. Before there could
be a phi for R1_R0, now there will be two for this case (assuming R0 and
R1 have one unit each).
The new methods return a range for easier iteration. Use them everywhere
instead of getImplicitUses, getNumImplicitUses, getImplicitDefs and
getNumImplicitDefs. A future patch will remove the old methods.
In some use cases the new methods are less efficient because they always
have to scan the whole uses/defs array to count its length, but that
will be fixed in a future patch by storing the number of implicit
uses/defs explicitly in MCInstrDesc. At that point there will be no need
to 0-terminate the arrays.
Differential Revision: https://reviews.llvm.org/D142215
The build breakages should be addressed by d4abdd2e3d:
[CMake] Check CMAKE_CXX_STANDARD and error if it's to old
Thanks to Tobias and Roy for addressing these issues.
This reverts commit 7f230feeeac8a67b335f52bd2e900a05c6098f20.
Breaks CodeGenCUDA/link-device-bitcode.cu in check-clang,
and many LLVM tests, see comments on https://reviews.llvm.org/D121169
RDF is designed to be target agnostic. Therefore it would be useful to have it available for other targets, such as X86.
Based on a previous patch by Krzysztof Parzyszek
Differential Revision: https://reviews.llvm.org/D75932
