Rework arm fast isel branch and compare code.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114226 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Eric Christopher 2010-09-17 22:28:18 +00:00
parent c2b768f09e
commit a5b1e68107

View File

@ -694,7 +694,54 @@ bool ARMFastISel::ARMSelectStore(const Instruction *I) {
if (!ARMEmitStore(VT, SrcReg, Reg, Offset /* 0 */)) return false;
return false;
return true;
}
static ARMCC::CondCodes getComparePred(CmpInst::Predicate Pred) {
switch (Pred) {
// Needs two compares...
case CmpInst::FCMP_ONE:
case CmpInst::FCMP_UEQ:
default:
assert(false && "Unhandled CmpInst::Predicate!");
return ARMCC::AL;
case CmpInst::ICMP_EQ:
case CmpInst::FCMP_OEQ:
return ARMCC::EQ;
case CmpInst::ICMP_SGT:
case CmpInst::FCMP_OGT:
return ARMCC::GT;
case CmpInst::ICMP_SGE:
case CmpInst::FCMP_OGE:
return ARMCC::GE;
case CmpInst::ICMP_UGT:
case CmpInst::FCMP_UGT:
return ARMCC::HI;
case CmpInst::FCMP_OLT:
return ARMCC::MI;
case CmpInst::ICMP_ULE:
case CmpInst::FCMP_OLE:
return ARMCC::LS;
case CmpInst::FCMP_ORD:
return ARMCC::VC;
case CmpInst::FCMP_UNO:
return ARMCC::VS;
case CmpInst::FCMP_UGE:
return ARMCC::PL;
case CmpInst::ICMP_SLT:
case CmpInst::FCMP_ULT:
return ARMCC::LT;
case CmpInst::ICMP_SLE:
case CmpInst::FCMP_ULE:
return ARMCC::LE;
case CmpInst::FCMP_UNE:
case CmpInst::ICMP_NE:
return ARMCC::NE;
case CmpInst::ICMP_UGE:
return ARMCC::HS;
case CmpInst::ICMP_ULT:
return ARMCC::LO;
}
}
bool ARMFastISel::ARMSelectBranch(const Instruction *I) {
@ -703,18 +750,28 @@ bool ARMFastISel::ARMSelectBranch(const Instruction *I) {
MachineBasicBlock *FBB = FuncInfo.MBBMap[BI->getSuccessor(1)];
// Simple branch support.
unsigned CondReg = getRegForValue(BI->getCondition());
// TODO: Hopefully we've already handled the condition since we won't
// have left an update in the value map. See the TODO below in ARMSelectCMP.
Value *Cond = BI->getCondition();
unsigned CondReg = getRegForValue(Cond);
if (CondReg == 0) return false;
unsigned CmpOpc = isThumb ? ARM::t2CMPrr : ARM::CMPrr;
ARMCC::CondCodes ARMPred = ARMCC::NE;
CmpInst *CI = dyn_cast<CmpInst>(Cond);
if (!CI) return false;
// Get the compare predicate.
ARMPred = getComparePred(CI->getPredicate());
// We may not handle every CC for now.
if (ARMPred == ARMCC::AL) return false;
unsigned BrOpc = isThumb ? ARM::t2Bcc : ARM::Bcc;
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(CmpOpc))
.addReg(CondReg).addReg(CondReg));
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(BrOpc))
.addMBB(TBB).addImm(ARMCC::NE).addReg(ARM::CPSR);
.addMBB(TBB).addImm(ARMPred).addReg(CondReg);
FastEmitBranch(FBB, DL);
FuncInfo.MBB->addSuccessor(TBB);
return true;
return true;
}
bool ARMFastISel::ARMSelectCmp(const Instruction *I) {
@ -730,17 +787,21 @@ bool ARMFastISel::ARMSelectCmp(const Instruction *I) {
return false;
unsigned CmpOpc;
unsigned DestReg;
switch (VT.getSimpleVT().SimpleTy) {
default: return false;
// TODO: Verify compares.
case MVT::f32:
CmpOpc = ARM::VCMPES;
DestReg = ARM::FPSCR;
break;
case MVT::f64:
CmpOpc = ARM::VCMPED;
DestReg = ARM::FPSCR;
break;
case MVT::i32:
CmpOpc = isThumb ? ARM::t2CMPrr : ARM::CMPrr;
DestReg = ARM::CPSR;
break;
}
@ -759,7 +820,8 @@ bool ARMFastISel::ARMSelectCmp(const Instruction *I) {
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
TII.get(ARM::FMSTAT)));
// TODO: How to update the value map when there's no result reg?
// Update the value to the implicit def reg.
UpdateValueMap(I, DestReg);
return true;
}