Revert r236546, "propagate IR-level fast-math-flags to DAG nodes (NFC)"

[oota-llvm.git] / lib / CodeGen / IfConversion.cpp

diff --git a/lib/CodeGen/IfConversion.cpp b/lib/CodeGen/IfConversion.cpp
index 938c9cf603910d5eeca27c1ae57abfa0adae3ed7..3ac78b258540db94132c38796aee8cb6dafefa65 100644 (file)
--- a/lib/CodeGen/IfConversion.cpp
+++ b/lib/CodeGen/IfConversion.cpp
@@ -985,6 +985,19 @@ static void UpdatePredRedefs(MachineInstr *MI, LivePhysRegs &Redefs) {
     // take a mutable instruction instead of const.
     MachineInstr *OpMI = const_cast<MachineInstr*>(Op.getParent());
     MachineInstrBuilder MIB(*OpMI->getParent()->getParent(), OpMI);
+    if (Op.isRegMask()) {
+      // First handle regmasks.  They clobber any entries in the mask which
+      // means that we need a def for those registers.
+      MIB.addReg(Reg.first, RegState::Implicit | RegState::Undef);
+
+      // We also need to add an implicit def of this register for the later
+      // use to read from.
+      // For the register allocator to have allocated a register clobbered
+      // by the call which is used later, it must be the case that
+      // the call doesn't return.
+      MIB.addReg(Reg.first, RegState::Implicit | RegState::Define);
+      continue;
+    }
     assert(Op.isReg() && "Register operand required");
     MIB.addReg(Reg.first, RegState::Implicit | RegState::Undef);
   }