Lower 64-bit immediates using MipsAnalyzeImmediate that has just been added.
Add a test case to show fewer instructions are needed to load an immediate
with the new way of loading immediates.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148908 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/Mips/MipsISelDAGToDAG.cpp b/lib/Target/Mips/MipsISelDAGToDAG.cpp
index 0194ed5..bdb7ca4 100644
--- a/lib/Target/Mips/MipsISelDAGToDAG.cpp
+++ b/lib/Target/Mips/MipsISelDAGToDAG.cpp
@@ -13,6 +13,7 @@
#define DEBUG_TYPE "mips-isel"
#include "Mips.h"
+#include "MipsAnalyzeImmediate.h"
#include "MipsMachineFunction.h"
#include "MipsRegisterInfo.h"
#include "MipsSubtarget.h"
@@ -317,6 +318,47 @@
break;
}
+ case ISD::Constant: {
+ const ConstantSDNode *CN = dyn_cast<ConstantSDNode>(Node);
+ unsigned Size = CN->getValueSizeInBits(0);
+
+ if (Size == 32)
+ break;
+
+ MipsAnalyzeImmediate AnalyzeImm;
+ int64_t Imm = CN->getSExtValue();
+
+ const MipsAnalyzeImmediate::InstSeq &Seq =
+ AnalyzeImm.Analyze(Imm, Size, false);
+
+ MipsAnalyzeImmediate::InstSeq::const_iterator Inst = Seq.begin();
+ DebugLoc DL = CN->getDebugLoc();
+ SDNode *RegOpnd;
+ SDValue ImmOpnd = CurDAG->getTargetConstant(SignExtend64<16>(Inst->ImmOpnd),
+ MVT::i64);
+
+ // The first instruction can be a LUi which is different from other
+ // instructions (ADDiu, ORI and SLL) in that it does not have a register
+ // operand.
+ if (Inst->Opc == Mips::LUi64)
+ RegOpnd = CurDAG->getMachineNode(Inst->Opc, DL, MVT::i64, ImmOpnd);
+ else
+ RegOpnd =
+ CurDAG->getMachineNode(Inst->Opc, DL, MVT::i64,
+ CurDAG->getRegister(Mips::ZERO_64, MVT::i64),
+ ImmOpnd);
+
+ // The remaining instructions in the sequence are handled here.
+ for (++Inst; Inst != Seq.end(); ++Inst) {
+ ImmOpnd = CurDAG->getTargetConstant(SignExtend64<16>(Inst->ImmOpnd),
+ MVT::i64);
+ RegOpnd = CurDAG->getMachineNode(Inst->Opc, DL, MVT::i64,
+ SDValue(RegOpnd, 0), ImmOpnd);
+ }
+
+ return RegOpnd;
+ }
+
case MipsISD::ThreadPointer: {
EVT PtrVT = TLI.getPointerTy();
unsigned RdhwrOpc, SrcReg, DestReg;