[llvm-commits] [llvm] r117085 - /llvm/trunk/lib/Target/ARM/ARMFastISel.cpp
Eric Christopher
echristo at apple.com
Thu Oct 21 18:28:00 PDT 2010
Author: echristo
Date: Thu Oct 21 20:28:00 2010
New Revision: 117085
URL: http://llvm.org/viewvc/llvm-project?rev=117085&view=rev
Log:
Add some basic ret instruction support to arm fast-isel.
Modified:
llvm/trunk/lib/Target/ARM/ARMFastISel.cpp
Modified: llvm/trunk/lib/Target/ARM/ARMFastISel.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/ARMFastISel.cpp?rev=117085&r1=117084&r2=117085&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/ARMFastISel.cpp (original)
+++ llvm/trunk/lib/Target/ARM/ARMFastISel.cpp Thu Oct 21 20:28:00 2010
@@ -132,6 +132,7 @@
bool SelectSRem(const Instruction *I);
bool SelectCall(const Instruction *I);
bool SelectSelect(const Instruction *I);
+ bool SelectRet(const Instruction *I);
// Utility routines.
private:
@@ -1440,6 +1441,69 @@
return true;
}
+bool ARMFastISel::SelectRet(const Instruction *I) {
+ const ReturnInst *Ret = cast<ReturnInst>(I);
+ const Function &F = *I->getParent()->getParent();
+
+ if (!FuncInfo.CanLowerReturn)
+ return false;
+
+ if (F.isVarArg())
+ return false;
+
+ CallingConv::ID CC = F.getCallingConv();
+ if (Ret->getNumOperands() > 0) {
+ SmallVector<ISD::OutputArg, 4> Outs;
+ GetReturnInfo(F.getReturnType(), F.getAttributes().getRetAttributes(),
+ Outs, TLI);
+
+ // Analyze operands of the call, assigning locations to each operand.
+ SmallVector<CCValAssign, 16> ValLocs;
+ CCState CCInfo(CC, F.isVarArg(), TM, ValLocs, I->getContext());
+ CCInfo.AnalyzeReturn(Outs, CCAssignFnForCall(CC, true /* is Ret */));
+
+ const Value *RV = Ret->getOperand(0);
+ unsigned Reg = getRegForValue(RV);
+ if (Reg == 0)
+ return false;
+
+ // Only handle a single return value for now.
+ if (ValLocs.size() != 1)
+ return false;
+
+ CCValAssign &VA = ValLocs[0];
+
+ // Don't bother handling odd stuff for now.
+ if (VA.getLocInfo() != CCValAssign::Full)
+ return false;
+ // Only handle register returns for now.
+ if (!VA.isRegLoc())
+ return false;
+ // TODO: For now, don't try to handle cases where getLocInfo()
+ // says Full but the types don't match.
+ if (VA.getValVT() != TLI.getValueType(RV->getType()))
+ return false;
+
+ // Make the copy.
+ unsigned SrcReg = Reg + VA.getValNo();
+ unsigned DstReg = VA.getLocReg();
+ const TargetRegisterClass* SrcRC = MRI.getRegClass(SrcReg);
+ // Avoid a cross-class copy. This is very unlikely.
+ if (!SrcRC->contains(DstReg))
+ return false;
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(TargetOpcode::COPY),
+ DstReg).addReg(SrcReg);
+
+ // Mark the register as live out of the function.
+ MRI.addLiveOut(VA.getLocReg());
+ }
+
+ unsigned RetOpc = isThumb ? ARM::tBX_RET : ARM::BX_RET;
+ AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
+ TII.get(RetOpc)));
+ return true;
+}
+
// A quick function that will emit a call for a named libcall in F with the
// vector of passed arguments for the Instruction in I. We can assume that we
// can emit a call for any libcall we can produce. This is an abridged version
@@ -1667,6 +1731,8 @@
return SelectCall(I);
case Instruction::Select:
return SelectSelect(I);
+ case Instruction::Ret:
+ return SelectRet(I);
default: break;
}
return false;
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