[mips][msa] Accept more values for constant splats

This patches teaches the MIPS backend to accept more values for constant
splats. Previously, only 10 bit signed immediates or values that could be
loaded using an ldi.[bhwd] instruction would be acceptted. This patch relaxes
that constraint so that any constant value that be splatted is accepted.

As a result, the constant pool is used less for vector operations, and the
suite of bit manipulation instructions b(clr|set|neg)i can now be used with
the full range of their immediate operand.

Reviewers: slthakur

Differential Revision: https://reviews.llvm.org/D30640

llvm-svn: 297457

1 files changed, 4 insertions, 5 deletions

diff --git a/llvm/lib/Target/Mips/MipsSEISelLowering.cpp b/llvm/lib/Target/Mips/MipsSEISelLowering.cpp
index 69162d4f6e8..c78c24bf47b 100644
--- a/llvm/lib/Target/Mips/MipsSEISelLowering.cpp
+++ b/llvm/lib/Target/Mips/MipsSEISelLowering.cpp
@@ -2529,11 +2529,10 @@ SDValue MipsSETargetLowering::lowerBUILD_VECTOR(SDValue Op,
         SplatBitSize != 64)
       return SDValue();
 
-    // If the value fits into a simm10 then we can use ldi.[bhwd]
-    // However, if it isn't an integer type we will have to bitcast from an
-    // integer type first. Also, if there are any undefs, we must lower them
-    // to defined values first.
-    if (ResTy.isInteger() && !HasAnyUndefs && SplatValue.isSignedIntN(10))
+    // If the value isn't an integer type we will have to bitcast
+    // from an integer type first. Also, if there are any undefs, we must
+    // lower them to defined values first.
+    if (ResTy.isInteger() && !HasAnyUndefs)
       return Op;
 
     EVT ViaVecTy;