GlobalISel: Support legalizing G_CONSTANT with irregular breakdown
llvm-svn: 358109
diff --git a/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp b/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
index 9fe0575..f563b8c 100644
--- a/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
@@ -473,6 +473,38 @@
MI.eraseFromParent();
return Legalized;
}
+ case TargetOpcode::G_CONSTANT: {
+ LLT Ty = MRI.getType(MI.getOperand(0).getReg());
+ const APInt &Val = MI.getOperand(1).getCImm()->getValue();
+ unsigned TotalSize = Ty.getSizeInBits();
+ unsigned NarrowSize = NarrowTy.getSizeInBits();
+ int NumParts = TotalSize / NarrowSize;
+
+ SmallVector<unsigned, 4> PartRegs;
+ for (int I = 0; I != NumParts; ++I) {
+ unsigned Offset = I * NarrowSize;
+ auto K = MIRBuilder.buildConstant(NarrowTy,
+ Val.lshr(Offset).trunc(NarrowSize));
+ PartRegs.push_back(K.getReg(0));
+ }
+
+ LLT LeftoverTy;
+ unsigned LeftoverBits = TotalSize - NumParts * NarrowSize;
+ SmallVector<unsigned, 1> LeftoverRegs;
+ if (LeftoverBits != 0) {
+ LeftoverTy = LLT::scalar(LeftoverBits);
+ auto K = MIRBuilder.buildConstant(
+ LeftoverTy,
+ Val.lshr(NumParts * NarrowSize).trunc(LeftoverBits));
+ LeftoverRegs.push_back(K.getReg(0));
+ }
+
+ insertParts(MI.getOperand(0).getReg(),
+ Ty, NarrowTy, PartRegs, LeftoverTy, LeftoverRegs);
+
+ MI.eraseFromParent();
+ return Legalized;
+ }
case TargetOpcode::G_ADD: {
// FIXME: add support for when SizeOp0 isn't an exact multiple of
// NarrowSize.
@@ -615,31 +647,6 @@
return reduceLoadStoreWidth(MI, 0, NarrowTy);
}
- case TargetOpcode::G_CONSTANT: {
- // FIXME: add support for when SizeOp0 isn't an exact multiple of
- // NarrowSize.
- if (SizeOp0 % NarrowSize != 0)
- return UnableToLegalize;
- int NumParts = SizeOp0 / NarrowSize;
- const APInt &Cst = MI.getOperand(1).getCImm()->getValue();
- LLVMContext &Ctx = MIRBuilder.getMF().getFunction().getContext();
-
- SmallVector<unsigned, 2> DstRegs;
- for (int i = 0; i < NumParts; ++i) {
- unsigned DstReg = MRI.createGenericVirtualRegister(NarrowTy);
- ConstantInt *CI =
- ConstantInt::get(Ctx, Cst.lshr(NarrowSize * i).trunc(NarrowSize));
- MIRBuilder.buildConstant(DstReg, *CI);
- DstRegs.push_back(DstReg);
- }
- unsigned DstReg = MI.getOperand(0).getReg();
- if(MRI.getType(DstReg).isVector())
- MIRBuilder.buildBuildVector(DstReg, DstRegs);
- else
- MIRBuilder.buildMerge(DstReg, DstRegs);
- MI.eraseFromParent();
- return Legalized;
- }
case TargetOpcode::G_SELECT:
return narrowScalarSelect(MI, TypeIdx, NarrowTy);
case TargetOpcode::G_AND:
