before. This is taken care of in the selection DAG pass. In my opinion, this
should be in one place or the other. I.e., it should probably be removed from
the DAG combiner (along with the other arithmetic transformations on constants
that are essentially no-ops).
llvm-svn: 55889
out of ScheduleDAGEmit.cpp and into SelectionDAGISel.cpp. This
allows it to be run exactly once per function, even if multiple
SelectionDAG iterations happen in the entry block, as may happen
with FastISel.
llvm-svn: 55863
but less accurate (non-IEEE) code sequences for
certain math library functions. Add the first of
several such expansions. Don't worry, if you don't
turn it on it won't affect you.
llvm-svn: 55823
HandlePHINodesInSuccessorBlocks that works FastISel-style. This
allows PHI nodes to be updated correctly while using FastISel.
This also involves some code reorganization; ValueMap and
MBBMap are now members of the FastISel class, so they needn't
be passed around explicitly anymore. Also, SelectInstructions
is changed to SelectInstruction, and only does one instruction
at a time.
llvm-svn: 55746
list that have internal linkage; the linker doesn't need
or want this. (These objects must still be preserved
at compile time, so just removing them from the llvm.used
list doesn't work.) Should affect only Darwin.
llvm-svn: 55722
the simple fix, materializing the constant before every use. It might be better to either track domination of uses or
to materialize all constants and the beginning of the function and let remat sort when to do materialization at uses.
llvm-svn: 55703
when searching for redundant subregister dead/kill bits.
Previously it was common to see instructions marked like this:
"RET %EAX<imp-use,kill>, %AX<imp-use,kill>"
With this change, addRegisterKilled continues scanning after
finding the %EAX operand, so it proceeds to discover the
redundant %AX kill and eliminates it, producing this:
"RET %EAX<imp-use,kill>"
This currently has no effect on the generated code.
llvm-svn: 55698
The first can update the SDNode in an SDValue
while the second is called with SDNode* and
returns a possibly updated SDNode*.
This patch has no intended functional impact,
but helps eliminating ugly temporary SDValues.
llvm-svn: 55608
assignment when selecting the def. This is the naive solution to the problem: insert a copy to the pre-chosen
vreg. Other solutions might be preferable, such as:
1) Passing the dest reg into FastEmit_. However, this would require the higher level code to know about reg classes, which they don't currently.
2) Selecting blocks in reverse postorder. This has some compile time cost for computing the order, and we'd need to measure its impact.
llvm-svn: 55555
its work by putting all nodes in the worklist, requiring a big
dynamic allocation. Now, DAGCombiner just iterates over the AllNodes
list and maintains a worklist for nodes that are newly created or
need to be revisited. This allows the worklist to stay small in most
cases, so it can be a SmallVector.
This has the side effect of making DAGCombine not miss a folding
opportunity in alloca-align-rounding.ll.
llvm-svn: 55498
SelectionDAGLowering instead of being in an anonymous namespace.
This fixes warnings about SelectionDAGLowering having fields
using anonymous namespaces.
llvm-svn: 55497
ATOMIC_LOAD_ADD_{8,16,32,64} instead of ATOMIC_LOAD_ADD.
Increased the Hardcoded Constant OpActionsCapacity to match.
Large but boring; no functional change.
This is to support partial-word atomics on ppc; i8 is
not a valid type there, so by the time we get to lowering, the
ATOMIC_LOAD nodes looks the same whether the type was i8 or i32.
The information can be added to the AtomicSDNode, but that is the
largest SDNode; I don't fully understand the SDNode allocation,
but it is sensitive to the largest node size, so increasing
that must be bad. This is the alternative.
llvm-svn: 55457
works with.
SelectionDAG, FunctionLoweringInfo, and SelectionDAGLowering
objects now get created once per SelectionDAGISel instance, and
can be reused across blocks and across functions. Previously,
they were created and destroyed each time they were needed.
This reorganization simplifies the handling of PHI nodes, and
also SwitchCases, JumpTables, and BitTestBlocks. This
simplification has the side effect of fixing a bug in FastISel
where successor PHI nodes weren't being updated correctly.
This is also a step towards making the transition from FastISel
into and out of SelectionDAG faster, and also making
plain SelectionDAG faster on code with lots of little blocks.
llvm-svn: 55450
of two, and to not need a scratch std::vector. Also, compute the ordering
immediately in the result array, instead of in another scratch std::vector
that is copied to the result array.
llvm-svn: 55421
of two, and to not need a scratch std::vector. Also, use the
SelectionDAG's topological sort in LegalizeDAG instead of having
a separate implementation.
llvm-svn: 55389
was inserted or not. This allows bitcast in fast isel to properly handle the case
where an appropriate reg-to-reg copy is not available.
llvm-svn: 55375
RecyclingAllocator, but this change is needed for the nodes
to actually be recycled. This cuts SelectionDAG's memory
usage high-water-mark in half in some cases.
llvm-svn: 55351
Bill Wendling