[mips][msa] Remove the VSPLAT and VSPLATD nodes in favour of matching BUILD_VECTOR.

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.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191299 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 0 insertions, 6 deletions

diff --git a/lib/Target/Mips/MipsISelLowering.h b/lib/Target/Mips/MipsISelLowering.h
index 0d588c1d2a..ae82e7e7ed 100644
--- a/lib/Target/Mips/MipsISelLowering.h
+++ b/lib/Target/Mips/MipsISelLowering.h
@@ -172,12 +172,6 @@ namespace llvm {
       VUMAX,
       VUMIN,
 
-      // Special case of BUILD_VECTOR where all elements are the same.
-      VSPLAT,
-      // Special case of VSPLAT where the result is v2i64, the operand is
-      // constant, and the operand fits in a signed 10-bits value.
-      VSPLATD,
-
       // Combined (XOR (OR $a, $b), -1)
       VNOR,