Add TargetInstrInfo::isSafeToMoveRegisterClassDefs. It returns true if it's safe to move an instruction which defines a value in the register class. Replace pre-splitting specific IgnoreRegisterClassBarriers with this new hook.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63936 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86InstrInfo.cpp b/lib/Target/X86/X86InstrInfo.cpp
index 8e3985f..5778849 100644
--- a/lib/Target/X86/X86InstrInfo.cpp
+++ b/lib/Target/X86/X86InstrInfo.cpp
@@ -2483,11 +2483,11 @@
}
bool X86InstrInfo::
-IgnoreRegisterClassBarriers(const TargetRegisterClass *RC) const {
- // FIXME: Ignore bariers of x87 stack registers for now. We can't
+isSafeToMoveRegClassDefs(const TargetRegisterClass *RC) const {
+ // FIXME: Return false for x87 stack register classes for now. We can't
// allow any loads of these registers before FpGet_ST0_80.
- return RC == &X86::CCRRegClass || RC == &X86::RFP32RegClass ||
- RC == &X86::RFP64RegClass || RC == &X86::RFP80RegClass;
+ return !(RC == &X86::CCRRegClass || RC == &X86::RFP32RegClass ||
+ RC == &X86::RFP64RegClass || RC == &X86::RFP80RegClass);
}
const TargetRegisterClass *X86InstrInfo::getPointerRegClass() const {
diff --git a/lib/Target/X86/X86InstrInfo.h b/lib/Target/X86/X86InstrInfo.h
index 077de56..eba0baf 100644
--- a/lib/Target/X86/X86InstrInfo.h
+++ b/lib/Target/X86/X86InstrInfo.h
@@ -406,10 +406,9 @@
virtual
bool ReverseBranchCondition(SmallVectorImpl<MachineOperand> &Cond) const;
- /// IgnoreRegisterClassBarriers - Returns true if pre-register allocation
- /// live interval splitting pass should ignore barriers of the specified
- /// register class.
- bool IgnoreRegisterClassBarriers(const TargetRegisterClass *RC) const;
+ /// isSafeToMoveRegClassDefs - Return true if it's safe to move a machine
+ /// instruction that defines the specified register class.
+ bool isSafeToMoveRegClassDefs(const TargetRegisterClass *RC) const;
const TargetRegisterClass *getPointerRegClass() const;