[mips][msa] Fix generation of bm(n)zi and bins[lr]i instructions

We have two cases here, the first one being the following instruction
selection from the builtin function:
bm(n)zi builtin -> vselect node -> bins[lr]i machine instruction

In case of bm(n)zi having an immediate which has either its high or low bits
set, a bins[lr] instruction can be selected through the selectVSplatMask[LR]
function. The function counts the number of bits set, and that value is
being passed to the bins[lr]i instruction as its immediate, which in turn
copies immediate modulo the size of the element in bits plus 1 as per specs,
where we get the off-by-one-error.

The other case is:
bins[lr]i -> vselect node -> bsel.v

In this case, a bsel.v instruction gets selected with a mask having one bit
less set than required.

Patch by Stefan Maksimovic.

Differential Revision: https://reviews.llvm.org/D30579

llvm-svn: 299768

2 files changed, 4 insertions, 4 deletions

diff --git a/llvm/lib/Target/Mips/MipsSEISelDAGToDAG.cpp b/llvm/lib/Target/Mips/MipsSEISelDAGToDAG.cpp
index 9e854f8db6d..c9cf9363b8c 100644
--- a/llvm/lib/Target/Mips/MipsSEISelDAGToDAG.cpp
+++ b/llvm/lib/Target/Mips/MipsSEISelDAGToDAG.cpp
@@ -692,7 +692,7 @@ bool MipsSEDAGToDAGISel::selectVSplatMaskL(SDValue N, SDValue &Imm) const {
     // as the original value.
     if (ImmValue == ~(~ImmValue & ~(~ImmValue + 1))) {
 
-      Imm = CurDAG->getTargetConstant(ImmValue.countPopulation(), SDLoc(N),
+      Imm = CurDAG->getTargetConstant(ImmValue.countPopulation() - 1, SDLoc(N),
                                       EltTy);
       return true;
     }
@@ -724,7 +724,7 @@ bool MipsSEDAGToDAGISel::selectVSplatMaskR(SDValue N, SDValue &Imm) const {
     // Extract the run of set bits starting with bit zero, and test that the
     // result is the same as the original value
     if (ImmValue == (ImmValue & ~(ImmValue + 1))) {
-      Imm = CurDAG->getTargetConstant(ImmValue.countPopulation(), SDLoc(N),
+      Imm = CurDAG->getTargetConstant(ImmValue.countPopulation() - 1, SDLoc(N),
                                       EltTy);
       return true;
     }
diff --git a/llvm/lib/Target/Mips/MipsSEISelLowering.cpp b/llvm/lib/Target/Mips/MipsSEISelLowering.cpp
index 71bccc52482..e2da8477295 100644
--- a/llvm/lib/Target/Mips/MipsSEISelLowering.cpp
+++ b/llvm/lib/Target/Mips/MipsSEISelLowering.cpp
@@ -1644,7 +1644,7 @@ SDValue MipsSETargetLowering::lowerINTRINSIC_WO_CHAIN(SDValue Op,
     if (Op->getConstantOperandVal(3) >= EltTy.getSizeInBits())
       report_fatal_error("Immediate out of range");
     APInt Mask = APInt::getHighBitsSet(EltTy.getSizeInBits(),
-                                       Op->getConstantOperandVal(3));
+                                       Op->getConstantOperandVal(3) + 1);
     return DAG.getNode(ISD::VSELECT, DL, VecTy,
                        DAG.getConstant(Mask, DL, VecTy, true),
                        Op->getOperand(2), Op->getOperand(1));
@@ -1659,7 +1659,7 @@ SDValue MipsSETargetLowering::lowerINTRINSIC_WO_CHAIN(SDValue Op,
     if (Op->getConstantOperandVal(3) >= EltTy.getSizeInBits())
       report_fatal_error("Immediate out of range");
     APInt Mask = APInt::getLowBitsSet(EltTy.getSizeInBits(),
-                                      Op->getConstantOperandVal(3));
+                                      Op->getConstantOperandVal(3) + 1);
     return DAG.getNode(ISD::VSELECT, DL, VecTy,
                        DAG.getConstant(Mask, DL, VecTy, true),
                        Op->getOperand(2), Op->getOperand(1));