Most constant BUILD_VECTOR's are matched using ComplexPatterns which cover
bitcasted as well as normal vectors. However, it doesn't seem to be possible to
match ldi.[bhwd] in a type-agnostic manner (e.g. to support the widest range of
immediates, it should be possible to use ldi.b to load v2i64) using TableGen so
ldi.[bhwd] is matched using custom code in MipsSEISelDAGToDAG.cpp
This made the majority of the constant splat BUILD_VECTOR lowering redundant.
The only transformation remaining for constant splats is when an (up-to) 32-bit
constant splat is possible but the value does not fit into a 10-bit signed
integer. In this case, the BUILD_VECTOR is transformed into a bitcasted
BUILD_VECTOR so that fill.[bhw] can be used to splat the vector from a GPR32
register (which is initialized using the usual lui/addui sequence).
There are no additional tests since this is a re-implementation of previous
functionality. The change is intended to make it easier to implement some of
the upcoming instruction selection patches since they can rely on existing
support for BUILD_VECTOR's in the DAGCombiner.
compare_float.ll changed slightly because a BITCAST is no longer
introduced during legalization.
llvm-svn: 191299
Changes to MIPS SelectionDAG:
* Added nodes VEXTRACT_[SZ]EXT_ELT to represent extract and extend in a single
operation and implemented the DAG combines necessary to fold sign/zero
extends into the extract.
llvm-svn: 191199
Note: There's a later patch on my branch that re-implements this to select
build_vector without the custom SelectionDAG nodes. The future patch avoids
the constant-folding problems stemming from the custom node (i.e. it doesn't
need to re-implement all the DAG combines related to BUILD_VECTOR).
Changes to MIPS specific SelectionDAG nodes:
* Added VSPLAT
This is a special case of BUILD_VECTOR that covers the case the
BUILD_VECTOR is a splat operation.
* Added VSPLATD
This is a special case of VSPLAT that handles the cases when v2i64 is legal
llvm-svn: 191191
These intrinsics are legalized to V(ALL|ANY)_(NON)?ZERO nodes,
are matched as SN?Z_[BHWDV]_PSEUDO pseudo's, and emitted as
a branch/mov sequence to evaluate to 0 or 1.
Note: The resulting code is sub-optimal since it doesnt seem to be possible
to feed the result of an intrinsic directly into a brcond. At the moment
it uses (SETCC (VALL_ZERO $ws), 0, SETEQ) and similar which unnecessarily
evaluates the boolean twice.
llvm-svn: 189478
The MSA control registers have been added as reserved registers,
and are only used via ISD::Copy(To|From)Reg. The intrinsics are lowered
into these nodes.
llvm-svn: 189468
Note that all of these tests use ld.b and st.b for the loads and stores
regardless of the data size. This is because the definition of bitcast is
equivalent to a store/load sequence and DAG combiner accordingly folds bitcasts
to/from v16i8 into the load/store nodes to product load/store nodes with
type v16i8.
llvm-svn: 189333
Daniel Sanders