Handle comparison values we already have - this fixes the consumer-typeset

failure for llvm-gcc on arm fast isel.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117710 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Eric Christopher 2010-10-29 21:08:19 +00:00
parent 0995f20cfd
commit 0e6233bfd7

View File

@ -933,14 +933,75 @@ bool ARMFastISel::SelectBranch(const Instruction *I) {
MachineBasicBlock *FBB = FuncInfo.MBBMap[BI->getSuccessor(1)];
// Simple branch support.
// TODO: Try to avoid the re-computation in some places.
unsigned CondReg = getRegForValue(BI->getCondition());
if (CondReg == 0) return false;
// If we can, avoid recomputing the compare - redoing it could lead to wonky
// behavior.
// TODO: Factor this out.
if (const CmpInst *CI = dyn_cast<CmpInst>(BI->getCondition())) {
if (CI->hasOneUse() && (CI->getParent() == I->getParent())) {
const Type *Ty = CI->getOperand(0)->getType();
EVT VT = TLI.getValueType(Ty);
bool isFloat = (Ty->isDoubleTy() || Ty->isFloatTy());
if (isFloat && !Subtarget->hasVFP2())
return false;
unsigned CmpOpc;
unsigned CondReg;
switch (VT.getSimpleVT().SimpleTy) {
default: return false;
// TODO: Verify compares.
case MVT::f32:
CmpOpc = ARM::VCMPES;
CondReg = ARM::FPSCR;
break;
case MVT::f64:
CmpOpc = ARM::VCMPED;
CondReg = ARM::FPSCR;
break;
case MVT::i32:
CmpOpc = isThumb ? ARM::t2CMPrr : ARM::CMPrr;
CondReg = ARM::CPSR;
break;
}
// Get the compare predicate.
ARMCC::CondCodes ARMPred = getComparePred(CI->getPredicate());
// We may not handle every CC for now.
if (ARMPred == ARMCC::AL) return false;
unsigned Arg1 = getRegForValue(CI->getOperand(0));
if (Arg1 == 0) return false;
unsigned Arg2 = getRegForValue(CI->getOperand(1));
if (Arg2 == 0) return false;
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
TII.get(CmpOpc))
.addReg(Arg1).addReg(Arg2));
// For floating point we need to move the result to a comparison register
// that we can then use for branches.
if (isFloat)
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
TII.get(ARM::FMSTAT)));
unsigned BrOpc = isThumb ? ARM::t2Bcc : ARM::Bcc;
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(BrOpc))
.addMBB(TBB).addImm(ARMPred).addReg(ARM::CPSR);
FastEmitBranch(FBB, DL);
FuncInfo.MBB->addSuccessor(TBB);
return true;
}
}
unsigned CmpReg = getRegForValue(BI->getCondition());
if (CmpReg == 0) return false;
// Re-set the flags just in case.
unsigned CmpOpc = isThumb ? ARM::t2CMPri : ARM::CMPri;
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(CmpOpc))
.addReg(CondReg).addImm(1));
.addReg(CmpReg).addImm(1));
unsigned BrOpc = isThumb ? ARM::t2Bcc : ARM::Bcc;
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(BrOpc))