Be more layout aware here and swap the successor and branch condition
if it means we get a fallthrough.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130404 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMFastISel.cpp b/lib/Target/ARM/ARMFastISel.cpp
index c95b4a8..3e0b755 100644
--- a/lib/Target/ARM/ARMFastISel.cpp
+++ b/lib/Target/ARM/ARMFastISel.cpp
@@ -1132,9 +1132,16 @@
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(TstOpc))
.addReg(CmpReg).addImm(1));
+
+ unsigned CCMode = ARMCC::NE;
+ if (FuncInfo.MBB->isLayoutSuccessor(TBB)) {
+ std::swap(TBB, FBB);
+ CCMode = ARMCC::EQ;
+ }
+
unsigned BrOpc = isThumb ? ARM::t2Bcc : ARM::Bcc;
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(BrOpc))
- .addMBB(TBB).addImm(ARMCC::NE).addReg(ARM::CPSR);
+ .addMBB(TBB).addImm(CCMode).addReg(ARM::CPSR);
FastEmitBranch(FBB, DL);
FuncInfo.MBB->addSuccessor(TBB);
return true;